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Über dieses Buch

As the world’s population continues to expand, maintaining and indeed increasing agricultural productivity is more important than ever, though it is also more difficult than ever in the face of changing weather patterns that in some cases are leading to aridity and desertification. The absence of scientific soil inventories, especially in arid areas, leads to mistaken decisions about soil use that, in the end, reduce a region’s capacity to feed its population, or to guarantee a clean water supply. Greater efficiency in soil use is possible when these resources are properly classified using international standards. Focusing on arid regions, this volume details soil classification from many countries. It is only once this information is properly assimilated by policymakers it becomes a foundation for informed decisions in land use planning for rational and sustainable uses.

Inhaltsverzeichnis

Frontmatter

Soil Survey and Classification Strategies in Different Ecological Zones

Frontmatter

Chapter 1. Innovative Thinking for Sustainable Use of Terrestrial Resources in Abu Dhabi Emirate Through Scientific Soil Inventory and Policy Development

Abu Dhabi is the largest of the seven emirates that comprise the United Arab Emirates (UAE). The total area of the UAE is about 82,880 km

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. Abu Dhabi Emirate occupies more than 87% of mainland plus a string of coastal islands extending into the Arabian Gulf. The Emirate’s leaders and population have a close affinity with the land and believe that careful agricultural development will be an important part of its future destiny and should be undertaken on a sustainable basis. With this aim, fourth-order extensive survey of Abu Dhabi Emirate was initiated in 2006 and completed in 2009. The field survey was completed through investigating 22,000 sites covering 5.5 × 10

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ha, supplemented with typical profiles description, ­laboratory analyses of soil samples, deep drilling to explore deep terrestrial resources, infiltration, permeability, and penetration resistance measurement. The survey was designed to take advantage of the latest technologies such as geographic information system (GIS), satellite image processing, and statistical analysis to produce

state-of-the-art

soil products. Sixty-two families and phases of soil families and 114 soil map units have been identified. The information were then used to publish soil map (1:100,000 and 1:500,000 scales) and 20 thematic maps at 1:500,000 scale. Using the extensive survey results, irrigated suitability map was prepared that led to delineate 1 million ha area, from which an area of 447,906 ha was surveyed at second-order level of USDA. The information collected will serve as a guide for future research and help to develop strategies that reduce the negative impact of the human activities on the natural surroundings and assist in the wise and sustainable use of its natural resources. In this chapter, methodologies used for extensive survey and results are presented and discussed for various uses. A brief introduction of the Abu Dhabi Soil Information System (ADSIS) developed to host all data for future retrieval, upgradation, and uses is also given, and policy issues are discussed.

Shabbir A. Shahid, Mahmoud A. Abdelfattah, Yasser Othman, Anil Kumar, Faisal K. Taha, John A. Kelley, Michael A. Wilson

Chapter 2. Demands on Soil Classification and Soil Survey Strategies: Special-Purpose Soil Classification Systems for Local Practical Use

Classifying soils for a particular purpose involves the ordering of soils into groups with similar properties and for potential end uses. The classification of soil is a terrific conceptual and practical challenge, especially in arid environments. The challenge may spur on, or it may deter scientists or end users with an interest in soils. If a classification system proves to be relevant and user-friendly, it stimulates and encourages further work because it is recognised for its inherent capacity to create order and enhance the useful understanding and mapping of soils. General-purpose, internationally recognised soil classification systems such as Soil Taxonomy and the World Reference Base and other nationally recognised classification systems (e.g. Australian or South African) have proved to be tremendously useful for soil classification and advancing understanding of soils across the world. However, because the use of these general-purpose classifications requires considerable expertise and experience, there is a need for complementary special-purpose classification systems that are specifically tailored, for example, to particular environmental problems, land uses or local regions and that use plain language descriptions for soil types. General-purpose classification systems often lag in the incorporation of new terminologies, for example, classification of acid sulfate soils in the Murray-Darling Basin, Australia, has led to descriptions of soil types with subaqueous properties (submerged underwater), monosulfidic materials and hypersulfidic materials, to enable assessment of environmental risk and management options. In addition, new challenges face general-purpose soil classification systems, especially in response to the following questions most frequently asked by soil users: (1) what soil properties are changing vertically and laterally in landscapes and with time, especially in acid sulfate soils? and (2) what are the most suitable approaches for characterising, monitoring, predicting and managing soil changes for environmental impact assessments, pollution incidents, waste management, product development and technology support? The purpose of this chapter is to address these challenges by presenting new ideas and concepts on how best to predict and solve practical problems by focussing on the development of special-purpose or more technical soil classification systems, which use plain language names for soil types. To demonstrate the critical importance of developing special-purpose technical soil classifications, the following five case studies are presented, which tackle difficult problems involving highly complex issues: (1 and 2) soil and water degradation in large aquatic environments from the River Murray and Lower Lakes region in South Australia (changing climatic and anthropogenic modified environments) and from the Mesopotamian marshlands in Iraq (anthropogenic modified arid environment); (3) acid sulfate soil as a new geochemical sampling medium for mineral exploration; (4) soil damage to the Australian telecommunication optic fibre cable network from shrink-swell soils and soil corrosion; and (5) soil landscape features to assist police in locating buried objects in complex terrain.

R. W. Fitzpatrick

Chapter 3. Reconnaissance Soil Survey for the State of Kuwait

In 1999, the government of Kuwait in collaboration with international consultant (AACM) completed a soil survey project at two levels: reconnaissance at scale 1:100,000 and a semi-detailed at scale 1:25,000. The survey followed the latest USDA-NRCS norms and standards for the fourth-order extensive soil survey, called as reconnaissance survey. Field mapping was completed by describing one point per 200 ha making a total of 8,400 observation points in the entire state, covering an area of 16,800 km

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. To support field mapping, 105 typical soil profiles representing different soil taxa were described, and 570 horizons were sampled and analyzed for their physical, chemical, engineering, and mineralogical characteristics. Eight diagnostic horizons and eight soil great groups (Haplocalcids, Petrocalcids, Haplogypsids, Calcigypsids, Petrogypsids, Aquisalids, Torriorthents, and Torripsamments) were mapped. Of 12 soil orders distributed worldwide, only two Aridisols and Entisols were mapped. Aridisols occupy 70.8% and Entisols 29.2% of the surveyed area. A total of 23 soil taxa at the family level of USDA soil taxonomy hierarchy were mapped and included as major and minor components of 71 soil map units. The survey results were interpreted for several uses and translated to a number of thematic maps such as sand and gravel sources and uses for shallow excavations, septic tanks, sewage lagoons, sanitary landfills (area and trench), seedling mortality, and herbaceous desert plants. The major outcome was the delineation of 207,309 ha area with highest potential for irrigated agriculture, this area was surveyed at the second-order (semi-detailed) level of USDA-NRCS standards, and suitability map for irrigated agriculture was prepared. The reconnaissance survey results are valuable source to base future land-use planning and will serve as a guide for decision makers and land-use planners. The reader is referred to (KISR, Soil survey for the State of Kuwait – vol II Reconnaissance survey. AACM International, Adelaide, 1999) for details of these interpretations.

Samira A. S. Omar, Shabbir A. Shahid

Chapter 4. Do the Emerging Methods of Digital Soil Mapping Have Anything to Learn from the Geopedologic Approach to Soil Mapping and Vice Versa?

The use of soil maps and the feasibility of the existing soil survey procedure are often questioned by both surveyors and users. Thanks to the advances in the fields of remote sensing (RS) and geographic information system (GIS), a new trend – digital soil mapping – is emerging which might have answers to some of the questions. With a glance to some of the definitions and concepts, such as ‘what is a soil?’ and ‘what is the content of a soil map?’ we intend to highlight the complexity of the soil and its mapping. At the same time, we apply some of the geopedologic-oriented techniques of the digital terrain modelling to soil mapping in order to show the role of geomorphology in the mapping. The exercise was carried out as case studies in several areas in Thailand. Various soils at subgroup levels (Fluventic, Arenic, Aquic, Aeric, Ultic, Ustic, Vertic) belonging to the soil orders Entisols, Mollisols, Inceptisols, Alfisols, and Ultisols occur in different geomorphic surfaces, following well the physiographic setup of the landscapes. The case studies demonstrate the conventional predictive mapping (the ITC approach) and the geopedologic approach to soil survey, based on parameterisation of the soil-forming factors and their integration: in one case through applying decision trees, followed up by a statistical validation, and in another case by means of Artificial Neural Network (ANN). It is hoped to open up a discussion, which should lead to (1) clarifying the term ‘digital soil mapping’ and (2) finding out whether or not the shortcomings of the conventional approach of soil mapping can be recovered using the new trend and does the new trend suggest changes in the current definitions and concepts.

Abbas Farshad, Dhruba Pikha Shrestha, Ruamporn Moonjun

Chapter 5. Soil Thematic Map and Land Capability Classification of Dubai Emirate

The soils of Dubai were mapped using remote-sensing satellite data (IRS-P6 LISS-IV) at 1:25,000 scale and classified to soil series level and their associations as per the USDA-NRCS Keys to Soil Taxonomy. A total of 26 soil series have been identified in Dubai Emirate, of which 13 were identified in Hatta area. The soils in general are coarse textured, sandy, highly calcareous and least developed. In the coastal and low-lying areas and depressions, the soils are highly saline; in the inland, soils are either saline or sodic. The Hatta area is characterized by mountains with steep side slopes, which are devoid of vegetation. Almost all the hills are barren (80–90%) and rocky without any soil cover. The soils in the hilly area are shallow to very shallow, skeletal in nature and highly calcareous. The soils have been assessed for land capability classes, and 17% of the total study area falls under land capability class IV, with the major limitations of climate and soil characteristics. These soils are suitable for marginal agriculture with the condition that sufficient water is available to offset water requirements of crops. The dominant land capability class identified in Dubai Emirate is class VI covering 65% of the study area. The dominant land capability class in Hatta is class VIII. Thus, the soil has major limitations of climate and soil which can be improved by adopting various soil conservation measures like sand dune levelling and stabilization, shelter belts and afforestation.

Hussein Harahsheh, Mohamed Mashroom, Yousef Marzouqi, Eman Al Khatib, B. R. M. Rao, M. A. Fyzee

Chapter 6. Land Evaluation Interpretations and Decision Support Systems: Soil Survey of Abu Dhabi Emirate

The soil survey of Abu Dhabi Emirate was completed in two stages, the extensive (4th-order level) and intensive (2nd-order) levels of USDA-NRCS classification system. Both surveys have generated an enormous amount of primary soils data that is now available to land use planners and decision-makers in the Emirate. The soil information provides farmers, land managers, planners and the like with baseline information upon which they can base future land use and environmental management decisions and policies. As such, the information can be regarded as a great asset for future generations of the UAE. The information is stored in the Abu Dhabi Soil Information System (ADSIS) database that has been designed to provide ready online access to users. In its raw form, the majority of the soil data is only usable by specialist soil scientists and geoscientists. Land evaluation methods provide a mechanism for the soil information to be synthesised, simplified, interpreted and presented to a far wider audience. Several land evaluations were conducted on the extensive and intensive data sets generated by the soil survey of Abu Dhabi Emirate. They included assessments to identify soils suitable for the generalised land use irrigated agriculture, which was subsequently used to delineate areas for more detailed examination in the intensive survey. Assessments of other land uses including afforestation, range management, recreation, urban development, construction material and sanitary landfill were also conducted. These assessments can be used to identify the potentials and limitations of soils for the different land uses. However, a more detailed analytical and modelling approach is required to extract the full worth of the data set and solve complex management issues such as sustainable irrigation practices for intensive agricultural development in the Emirate.

Peter King, Gerard Grealish, Shabbir A. Shahid, Mahmoud A. Abdelfattah

Chapter 7. Conceptual Soil-Regolith Toposequence Models to Support Soil Survey and Land Evaluation

Soil maps and the accompanying soil survey report are used to portray the spatial variation of soils in landscapes by indicating what soils, their proportion and their soil properties are likely to occur at a particular location or within a soil map unit. Soil surveyors intuitively understand this soil variation and how it may occur by reading the landscape. However, soil maps and soil survey reports are often too technical and not easily understood by land managers and decision-makers who are not specialist soil scientists. This chapter demonstrates how conceptual soil-regolith toposequence models can be used to describe (supporting soil survey map data and reports), explain (providing an understanding of the processes) and predict (supporting land evaluation) soil spatial variability in a range of complex landscapes. Case studies from Australia and Brunei are provided to illustrate how soil toposequence models are critical to explain, predict and solve practical land use problems, especially in complex soil-landscape environments. These conceptual models provide the following critical data to support land evaluation and ­management decisions by illustrating soil properties that are changing in time and space, which is especially important in salt-affected and acid sulphate soils (e.g. seasonal and climatic changes in occurrences of salt efflorescences), and the most suitable approaches for characterising, monitoring, predicting, managing and displaying soil changes for environmental impact assessments, pollution incidents, waste management and technology support.

Gerard Grealish, R. W. Fitzpatrick, Peter King, Shabbir A. Shahid

Chapter 8. Anhydrite Formation on the Coastal Sabkha of Abu Dhabi, United Arab Emirates

A fluvial marine sabkha along the coastal area of Abu Dhabi, United Arab Emirates, is hypersaline from evaporative losses of groundwater originating from rain, seawater intrusion, lagoons that border the sabkha, and inland groundwater sources. Anhydrite (CaSO

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) is present in these soils and is regarded to be both a neoformed mineral and a product of gypsum transformation. Six pedons (designated 1–6) were described, sampled, and characterized from a 13-km transect across the sabkha in order to better understand the distribution of anhydrite across the sabkha, determine suitable laboratory methods for detection and quantification of this mineral, and evaluate soil genesis and mineral formation. Soils were highly saline with electrical conductivity (EC1:2) ranging from 11 to 167 dS m

−1

. Evaporative minerals identified by x-ray diffraction include calcite, gypsum, halite, aragonite, and anhydrite. Together, salts, gypsum, and anhydrite composed 5–100% of the mineral matter of sabkha soils. Quantification of anhydrite was achieved by the difference in the acetone method (gypsum  +  anhydrite quantification) and low-temperature weight loss (for gypsum quantification). Both a thermal gravimetric analyzer (TGA) and an oven were tested for the latter procedure. The TGA method was found to provide the most reliable data, while the oven method yielded inconsistent results. Anhydrite was identified in the two sites (pedons 5 and 6) most distant from the coast, ranging up to 43% of the <2-mm fraction and occurring in thicknesses of 70 and 55 cm, respectively.

Michael A. Wilson, Shabbir A. Shahid, Mahmoud A. Abdelfattah, John A. Kelley, James E. Thomas

Chapter 9. Fundamental Steps for Regional and Country Level Soil Surveys

The spatial and temporal data and information are essential for decision and policy making within each governing system as well as in conservation and sustainable management programs through the execution of soil surveys. The soil survey data are used to establish national and regional level databases. A unique method of soil survey was executed to map some soil attributes in 300,000 ha of Zayandeh-rud Valley, Isfahan, Central Iran. To establish a powerful database, it is important that soil surveys address the environmental impacts. To do so, the following steps were considered: (1) fundamental factors and processes for landscape formation, (2) evolution pathways of geomorphic surfaces, and (3) mapping of pedologic properties and visualization of collected information. Execution of mentioned steps highlighted some historical facts in study area. It has observed that some geomorphic surfaces have developed before Pleistocene period; the Zayandeh-rud River had three different pathways in Quaternary period; the pedodiversity indices are directly related to soil evolution and time; and the soil evolution pathways in this valley does not follow the convergence pathway of the Jenny’s theory. Results also indicate that the digitally extracted continuous maps have the ability to accurately show the spatial distribution of pedologic properties.

Norair Toomanian

Chapter 10. Assessment of Soil Diversity in Western Siberia Using WRB 2006

Soil classification has practical importance. It is a base for the mapping of soil resources, data registration, and development of land-use and soil management. In this study, during the period from 2000 to 2008, new data on soil cover, properties of its components, their genesis, and ecology have been collected in the semiarid and dry subhumid regions of Western Siberia. The study enables to upgrade information on soil variability, properties and to a certain extent filled the gap in fundamental knowledge of the area. New data includes soil genesis, soil properties, landscape, and environmental conditions of formation and the classification diversity. Basic types of soil cover disturbances and main reasons of its limited use have been discussed. In our opinion, the international soil classification system (IUSS, Working group WRB. World reference base for soil resources, 2nd edn. World Soil Resources Reports No 103. FAO, Rome, 2006; IUSS, Working group WRB. World reference base for soil resources, first update. World Soil Resources Reports No 103. FAO, Rome, 2007) addresses soil formation characteristics in semiarid and dry subhumid regions of Western Siberia fairly adequately. Present study has shown that great soil diversity exists, presenting 12 of 32 reference soil groups in the study area.

Elena N. Smolentseva

Chapter 11. Classification of the Topsoil Fabrics in Arid Soils of Central Asia

Existing data on the soil micromorphology of arid regions are sparse; in the present study, micromorphological features of a wide spectrum of arid soils in Russia, Uzbekistan, Kazakhstan, and Mongolia are studied to develop diagnostic criteria for the new substantive-genetic soil classification systems. The diversity, functioning, and resilience of arid soils are determined by the properties of their topsoil, which reflects the recent environment, whereas subsoil reflects the paleoenvironment. Each of three upper horizons (light-humus, solonetzic eluvial, and xero-humus) as recognized in the new Russian system of soil classification (2004) and which can be found in arid soils presents similar micromorphological features in different soils. However, present study reveals that, in a sequence of soils, there are some specific micromorphological features indicating the increasing trends of aridity. In a soil sequence with increasing aridity, the diagnostic horizons and properties are combined in a regular way corresponding to the changes in environmental conditions and soil-forming processes; at the same time, the sequence is in good agreement with diagnostic elements of substantive Russian and WRB classification systems. Thus, the arid soils present two groups: one with a distinct light-humus horizon, and the other with a xero-humus horizon composed of crusty and subcrusty subhorizons. These groups correspond to two different types of pedogenesis. The micromorphological features of the topsoil make it possible to identify the mechanisms of some phenomena, for example, aeolian deposition, structural rearrangement, dynamics of secondary carbonates, and cryptosolonetzic manifestations.

Marina Lebedeva, Maria Gerasimova, Dmitry Golovanov

Chapter 12. Digital Mapping of Gypsic Horizon Morphotypes and Soil Salinity in an Old Alluvial Piedmont Plain of Uzbekistan

The digital maps of soil salinity, gypsum, and gypsum pedofeatures in soils (gypsic calcisols, gypsisols, and solonchaks) of the Dzhizak experimental station (Uzbekistan) are compiled from the results of soil survey conducted during 1980 and 2008, using digital elevation model (DEM) and remote sensing data. The study area represents a part of the Golodnaya Steppe piedmont plain to the north of Turkestan ridge. The macro- and micromorphological descriptions of gypsic horizons made it possible to distinguish three different morphotypes. The morphological features of gypsic horizons were classified, and their distribution map was prepared using GIS tool. The spatial distribution of different morphotypes of gypsic horizons showed distinct correlations with the soil salinity, the groundwater level, and the character of soil water regime. It was established that the presence of different gypsic horizons should be taken into account in the new substantive-genetic classification of Russian soils at high taxonomic levels. Studies completed after 20 years, when the groundwater level dropped by about 1 m, confirmed that the gypsum content decreased in soils; however, the major morphotypes were preserved. The micromorphological investigations demonstrated that certain changes took place in the microfabric of gypsum pedofeatures. Thus, fine dispersed crystals of gypsum disappeared from the soil profiles, and the number of pseudomorphic substitutions of calcite for gypsum crystals increased significantly attesting to the progressive calcification of soil profiles.

Dmitry L. Golovanov, Irina A. Yamnova

Chapter 13. Soils in Arid and Semiarid Regions: The Past as Key for the Future

Growing populations, increasing food demand, and technological advances may soon lead to intensifying land use in semiarid and arid countries through the spread of irrigated agriculture. Improved water harvesting and desalinization technology, coupled with higher efficiency of regenerative energies, might allow to widely extend irrigated areas. While this is a positive development in the light of growing demands for water and food, it presents challenges for land-use planners. Negative examples like Lake Aral make clear that a careful analysis is required before embarking on large-scale irrigation projects.

Soils are central for assessing the impacts of irrigation in the desert. For long-term projects as outlined above, it is insufficient to consider only the present soil distribution. It should also be considered how soils will change under irrigation. In this context, the past is a key for the future, since the modeling of future soil development can be calibrated using reconstructions. Soil surveys which consider the archival role of soils and sediments can partly be used to understand the landscape history and identify risk areas. Paleosols can be evaluated as indicators how changes of moisture availability will affect soil properties and which time frames are involved. This can be coupled with modeling of future soil development. A major methodological challenge for this approach is the use of different parameters and time frames in reconstruction and modeling, which have to be “translated” using experimentally determined relationships.

Long-term, large-scale irrigation in arid regions will mean a significant change of the environment and a departure from the conservative idea of sustainability, toward a concept which has been named “progressive development.” Its success chances depend largely on our understanding and correct prediction of the consequences of man-made changes of the environment.

Bernhard Lucke, Iourii Nikolskii, Rupert Bäumler

Chapter 14. Classification, Characterization, and Suitability Evaluation of the Savanna Soils of Oyo North of Nigeria

A detailed soil survey of about 100 ha of Savanna ecoclimatic region of Oyo North of Nigeria was carried out to characterize and classify the soils and to assess the potential of the area for agricultural suitability. During this study, five soil mapping units were identified and delineated. Selected physical and chemical characteristics were determined to support soil taxonomy, FAO–UNESCO legend, and land fertility capability classification. Five soil pedons were classified according to USDA soil taxonomy as Arenic Kandiudults, Arenic Kanhapludults, Typic Kandiudults, Arenic Kandiudalfs, and Gross Arenic Kandiudalfs and according to FAO–UNESCO system as Ferric Lixisols, Stagnic Lixisols, and Haplic Lixisols, respectively. The studied pedons are assessed for fertility capability classification (FCC), and their FCC (Buol classification) is recognized as sandy topsoil (S), low CEC (e), and K deficient (k) and presented as pedon 1 and 2 as Sek (>35% gravels), pedon 3 as Sek (2–4% slope and >35% gravels), pedon 4 as Sek (4–7% slope and >35% gravels), and pedon 5 as Lek (>7% slope and >35% gravels). Sand-sized particles dominate in the entire profiles. The exchangeable bases are generally low, and the exchange sites are dominated by calcium. Total N and organic matter contents are also low. The soils are marginally suitable for commonly grown crops such as cassava, maize, and oil palm. Limitations to agricultural production include soil fertility (CEC), organic matter, poor texture, and climate (rainfall and length of dry season).

J. O. Aruleba, A. S. Ajayi

Chapter 15. Use of Soil Survey Database for the Probabilistic Evaluation of Soil Cover Transformation in the Semiarid Zone of Western Siberia

The knowledge of soil properties, state of soil cover, and soil-forming processes is necessary for the understanding of landscapes and to plan ameliorative and engineering approaches for reclamation and their uses for agricultural purposes. In the semiarid zone of Western Siberia, it has been shown that the soil survey database can be used for probabilistic estimations and modeling of soil cover changes. Probability distributions were determined for chestnut soil properties, which are suitable for the reliable and holistic evaluation of the effect of soil-forming factors on soil properties and, hence, for comparisons of current and future anthropogenic and natural changes. The divergence of soil properties under deflation, long-term plowing, and irrigation by low-mineralized water with sodium bicarbonate was investigated.

Irina Mikheeva

Chapter 16. Soil Suitability of Northern State of Sudan to Irrigated Agriculture

A semi-detailed soil survey of 390,857 ha on both banks of the river Nile between the third and fourth cataracts, at an extent of approximately 400 km in the Northern State of Sudan, was carried out. The area lies within the desert climatic zone of Sudan. The objectives of the survey are to characterize soils and landscape and assess their suitability for irrigated agriculture and to provide guidance to agronomists and irrigation engineers for future land uses. Thirty-six soil map units were defined and grouped into five main units based on the contents of secondary calcium carbonate and soil texture. In this chapter, different soils, such as recent and sub-recent alluvial and high-terrace soils of Nile, desert plain soils, Nubian formation and soils of recent windblown sand and wadi deposits, are described. The soils are evaluated for irrigated agriculture suitability. The survey revealed recent and middle Nile alluvial soils (R) occupy 12%, Nile high-terrace soils (H) occupy 26%, desert plain soils (D) occupy 29%, Nubian formation soils (N) occupy 17%, and wadi deposits and windblown sand soils (S) occupy 16% of the survey area. Currently about one-third of the survey area is suitable for irrigated agriculture. A further 14% can be made suitable after the remedial work (mostly soil reclamation). Land that might be used in future for LUT 2 and LUT 3 amounts to a further 24% of the survey area, and the remainder 29% is unsuitable for irrigated agriculture.

Abdelmagid Ali Elmobarak, Fawzi Mohamed Salih

Chapter 17. Effects of Plants on Soil-Forming Processes: Case Studies from Arid Environments

Bulk deposits of aeolian sand accumulated over recent timescales provide instructive systems for examining effects of colonising vegetation on soil development. The two contrasting case studies presented here are eucalypt woodland in a dune system in southwest Australia and the rubified sand seas of the United Arab Emirates. In the former, clay pavements forming under the lateral root catchments of the eucalypts are shown to be constructed from iron, aluminium and other mineral elements abstracted from ground waters by deep roots. The pavements concerned have a marked restrictive influence on understorey density and biodiversity while also having an overall role in maximising effectiveness of usage of water and nutrients by the trees in question. Timescales and amounts of iron uplifted in this manner are estimated for the system. In the Arabian example, the occurrence of intense reddening (rubification) of sand towards the mountains of Oman is well known, and abiotic processes have been implicated in the phenomenon. In this chapter, we invoke involvement of a biotic component, having demonstrated a relationship between vegetation density and extent of rubification as seen in a positive correlation between increased reddening and cumulative vegetation encountered as one moves from coast to mountains. We hypothesise that uplift of iron by deep-rooted shrubs/trees might be the agent responsible for progressive reddening. Definitive testing of this hypothesis is required, particularly by analysing for iron in xylem sap flowing up through taproots and looking for evidence of its subsequent release into superficial layers of sand surrounding lateral roots of the trees.

William H. Verboom, John S. Pate, Mahmoud A. Abdelfattah, Shabbir A. Shahid

Chapter 18. The Sand Land Soil System Placement (Taxonomy) and Society

Arid soils of the world require different strategies for optimum land utilization due to the delicate balance between annual climatic cycles and general trends toward desertification. Arid lands are an irreplaceable natural resource covering one-third of the global land surface and harbor within them the potential to elevate the standards of living of more than two billion people. The soils of the arid areas are underutilized due to inadequate public knowledge of the soil system. In a modern age of precise measurements and categorization, it is time to use the available tools to greatly enhance the productivity and use of the soil system in general and arid soils in particular. Quantification of multifunctional and dynamic ecosystems within arid regions can provide opportunities for land users to diversify agroecological systems and for food security based upon well-defined representative soil units in each region. Thus, the soil scientists by considering soil as a system and correlating its taxonomic units would have the ability to extrapolate results of studies and by keeping “balance” between “inputs” and “outputs” in “soil system” would promote national productivity and regional economy. In this study, selected soils in various arid environmental and ecological regions of countries such as Ghana, Jordan, and Iran that have already been investigated (USDA soil taxonomy) to the level of soil series/farmland units on applicable scales will be compared to the soils of the Abu Dhabi Emirate.

Ramez A. Mahjoory

Chapter 19. Digital Soil Mapping Using Spectral and Terrain Parameters and Statistical Modelling Integrated into GIS-Northwestern Coastal Region of Egypt

This chapter examines digital soil mapping approach for the production of soil maps by using multinomial logistic regression on soil and terrain information from pilot areas in the northwestern coastal region of Egypt. The aim is to reproduce the original map and predict soil distribution in the adherent landscape. Reference soil maps produced by conventional methods at Omayed and Nagamish areas were used. The logit models of the soil classes as expressed by the spectral and terrain parameters were calculated, and predicted soil classes’ maps were produced. The IDRISI/SAGA/SATISTCA/SPSS platforms were used in this chapter. The terrain and spectral parameters were found to be significantly influential that the selection of the land surface predictors was satisfactory. The McFadden pseudo

R

-squares ranged from 0.473 to 0.496. The most significant terrain parameters influencing the spatial distribution of the soil classes are found to be elevation, valley depth, multiresolution ridgetop flatness index, multiresolution valley bottom flatness and SAGA wetness index. However, the most influential spectral parameters are the first two principle components of the six Enhanced Thematic Mapper bands. The overall accuracy of the predicted soil maps ranged from 72 to 74% with kappa index ranged from 0.62 to 0.64. The developed probability models were successfully used to predict the spatial distribution of the soil mapping units at pixel resolutions of 28.5 m × 28.5 m and 90 m × 90 m at adjacent unvisited areas at Matrouh and Alamin. The developed methodology could contribute to the allocation and to the digital mapping and management for new expansion sites in the remote desert areas of Egypt.

Fawzy Hassan Abdel-Kader

Chapter 20. Studies on the Micromorphology of Salt-Affected Soils from El-Fayoum Depression, Egypt

Salt-affected soils exhibit considerable areas in Egypt. Salt accumulation affects soil’s biological, physical, chemical, and micromorphological characteristics. Present study focuses on the identification of micromorphological features related to salinization processes in El-Fayoum area. The salts accumulate as surface crust, subsoil accumulation, and random salt distribution in the profile. The studied soils belong to three soil orders: Aridisols (Haplic Natrargids, Typic Haplosalids, and Typic Haplocalcids), Entisols (Vertic Torrifluents, Typic Torrifluvents, and Typic Torripsamments), and Vertisols (Typic Haplotorrerts). The thin section study under the polarizing microscope revealed spongy microstructure due to surface salt accumulation, occurrence of halite and gypsum crystals in voids and s-matrix, and medium to coarse calcified shell fragments distributed throughout the soil profiles, especially adjacent to saline Qaroun Lake. Other micromorphological features identified are subangular blocky microstructure in the Btz horizon of saline-sodic soil-presenting natric horizon; clay papules with high level of clay orientations in the form of sepic plasmic fabric; false micro-aggregates formed due to high level of salts, precipitated clay particles under sodic environment, which have a natric horizon in the presence of CaCO

3

more than 13%; and humus accumulations as highly humified debris and patches randomly distributed in s-matrix, especially in the topsoil.

Tolba S. Abdel Aal, A. M. Ibrahim

Chapter 21. Correlation of Students’ Estimation and Laboratory Determination of Soil Texture

Soil texture helps understand physical and chemical properties of soils. Soil texture can be determined accurately in the laboratory, or it can be estimated through finger test in the field, the accuracy of the latter depends on the skills and experience of the person. However, such estimates provide quick results compared to laboratory measurement, which takes ample amount of time for final results. In an attempt to correlate field and laboratory soil texture results, 11 students were trained to develop their skills to determine field soil texture (finger test) and in determining soil texture in the laboratory using standard hydrometer method. When the finger test results were compared with the laboratory results, the students’ estimates predicted the actual clay and sand percentages with high degree of accuracy. The results showed a high variation between student’s and laboratory determination of soil texture. Estimation of sand fraction is slightly more difficult than clay particles. This study suggests that students require more practice to be able to estimate soil textural class accurately. It is recommended that students should use reference samples (known texture) to improve their skills.

Mohamed S. Alhammadi, Mohamed S. Gheblawi

Chapter 22. Soil Classification and Genesis in Part of Khorasan Province

Saline and sodic soils occupy an important part of Iran including the vast area in Khorasan province. Also due to secondary salinization, some of the arable lands are becoming salt-affected. It is important to characterize and classify these soils for better management and uses. Preliminary interpretation of aerial photos and using topographic map, the area was divided into different physiographic units, that is, dominantly piedmont alluvial plains and flood plains. In these units, 30 soil profiles were dug and described, and soil samples from each genetic horizon were collected for physical and chemical characteristics using standard USDA methods. The aridic and thermic were recognized as moisture and temperature regimes, respectively. The gypsiferous and saliferous marls are the parent materials, being main factor for soil salinization. Topography, wind erosion and human activities also contributed to soil salinization. Micromorphological studies have revealed the presence of secondary gypsum and calcium carbonate in some pedons, forming gypsic and calcic horizons, respectively. The soils are classified according to the USDA soil taxonomy. Two soil orders (Aridisols, Entisols) and six suborders (calcids, salids, gypsids, cambids, fluvents and orthents) have been identified in the area, and a new subgroup of sodic torrifluvents is proposed.

Mohammad Hassan Sayyari-Zahan

Chapter 23. Classification, Characterization, and Management of Some Agricultural Soils in the North of Egypt

Present study is completed on soils developed from different sources and types of materials (fluvial, lacustrine, marine, sandy and fluvio-sandy, and calcareous deposits). These soils belong to orders entisols and aridisols. The diverse geological nature of the deposits on which these soils are developed is reflected in the wide variation of soil characteristics (morphologies, clay, cation-exchange capacity, carbonate equivalents, and oxides of Fe, Al, Si, and Mn). All soils are alkaline in reaction, ECe (salinity) ranges between 0.66 and 8.0 dS m

−1

, clay (6.2–57.5%), cation-exchange capacity (3.0–79.1 cmolc kg

−1

), organic matter (0.29–2.68%), and calcium carbonate equivalents (0.07–55.62%). Total Fe, Al, and Mn concentrations differed greatly between soils, and the majority of the Fe and Mn occurred in crystalline form. Aluminum oxides are amorphous especially in clayey soils. Total free Si was similar to or exceeded to those of amorphous Si in all soils except calcareous ones. The soils developed from different materials are classified, such as fluvial (Vertic Torrifluvents, Typic Torrifluvents, Typic Fluvaquents, and Typic Ustifluvents), lacustrine (Typic Xerofluvents and Typic Fluvaquents), marine (Typic Xeropsamments and Typic Psammiaquents), sandy (Typic Quartzipsamments and Typic Torripsamments), and calcareous (Typic Haplocalcids).

Sabry M. Shaheen, Mohamed E. Abo-Waly, Rafaat A. Ali

Chapter 24. Semiarid Soils of Eastern Indonesia: Soil Classification and Land Uses

Despite the high annual rainfall (2,000–5,000 mm) of Indonesia, 3.3 × 10

6

ha area of East Nusa Tenggara (NTT) province receives annual rainfall between 1,000 and 2,000 mm with 5–8 dry months (<100-mm rainfall), and about 1 × 10

6

ha area receives <1,000 mm annual rainfall with 8–10 dry months. About 1.7 × 10

6

ha land is mountainous (>30% slope), and 1.5 × 10

6

ha is hilly (15–30% slope). The steep slopes and high-intensity rainfall in rainy season cause high erosion and sedimentation. This results in >1-m soil depth at the valley bottom dominated by Haplustepts and Haplustolls, and <50-cm soil depth in the upper slope dominated by Lithic Ustorthents or Lithic Haplustepts. The soil reaction is acidic to slightly alkaline (pH 4.1–7.8), low to high organic carbon (1.2–5.4%), high to very high (25%-HCl extractable) P and K, moderate to high exchangeable cations (18–41 cmol(+) kg

−1

), and high base saturation percentage. About 2.4 × 10

6

ha land is suitable for agriculture, of which 0.5 × 10

6

ha occurs in the <1,000 mm; 1.7 × 10

6

ha in the 1,000–2,000 mm; and 0.2 × 10

6

ha in the >2,000 mm annual rainfall areas. Due to low rainfall, the recommended commodities were tailored to the availability of water. Based on soil characteristics and rainfall, recommendations are made for crop selection. Annual crops are recommended for the flat areas and valley bottoms, while perennial crops are recommended on the sloping areas. It is recommended, for example, for annual crops, adjustment of the planting time is to be made with the rainfall distribution, whereas for perennial crops, selection of those crops is to be made which require several months of dry period, such as candlenut, cashew nuts, kapok, and Jatropha.

Anny Mulyani, Adi Priyono, Fahmuddin Agus

Land Use Planning and Policy Implications

Frontmatter

Chapter 25. Land Use Planning and Policy Implication: Bridging Between Science, Politics and Decision Making

We describe land use planning based on the six main functions and uses of soil and land. Policy input is mainly needed to control the competition between different land uses, avoiding or minimising irreversible impacts. For achieving this, we describe an indicator framework, which allows for planning and controlling complex land use systems.

Winfried E. H. Blum

Chapter 26. Application of Soil Survey in Land Use Planning and Policy Development

Soils have a crucial role in addressing some of the key issues of our time, such as food security and climate change, and provide a key natural resource asset underpinning sustainable development. Until now, this role has largely been ignored in the policy debate. This situation is changing internationally, as the importance of the land in supporting our future survival and prosperity is increasingly realised. A soil management strategy providing a clear purpose and direction for policy development and a framework to coordinate activities is essential. A policy vision and a set of guiding principles to meet this challenge are proposed, and the value of good underpinning soil resource information is demonstrated. The soil survey of the Abu Dhabi Emirate, which delivers a soil and land resource dataset at a scale, accuracy and consistency required to support land use planning and policy development, is a significant achievement that should be applauded. The opportunities provided by this new comprehensive information to achieve sustainable development in the Abu Dhabi Emirate are immense.

Noel Schoknecht

Chapter 27. General Framework for Land Use Planning in United Arab Emirates

An integrated framework is presented for analyzing and evaluating land use planning to address growing land use pressures, taking into account the socioeconomic and environmental aspects and the effect of land use change on water resources in United Arab Emirates. In land use planning, it is essential to identify the current problems and then to find proper solutions and their implementation with the aim of planning toward long-term conservation and sustainable use of land resources. This chapter identifies areas of land with high value for conserving water resources to help public sector for their planning activities. A general spatial modeling framework using geographic information system (GIS) capabilities and based on land use suitability units is used for evaluating how planning alternatives could affect water resources and best satisfies defined policies. The framework is applied to United Arab Emirates as a case study. This framework is important for making decisions about land and water resource use, managing growth, growing land use pressures and cumulative effects, reconciling competing demands for land, and integrating land use policies. It is anticipated that the policy makers, land use planners, decision-makers, and engineers can benefit from the framework.

Khalil A. Ammar

Chapter 28. Spatial Mapping and Analysis of Integrated Agricultural Land Use and Infrastructure in Mhlontlo Local Municipality, Eastern Cape, South Africa

The study spatially mapped and analysed agriculture land use and infrastructure requirements in Mhlontlo Local Municipality linked to ASGISA Eastern Cape’s agrarian transformation and rural development initiatives. Emphasis was placed on informing ASGISA Eastern Cape’s broader rural infrastructure programme in support of agrarian transformation and rural development for the Eastern Cape province. The study approach was participatory, extensively involving discussions with stakeholders, visits to project areas, internal and external workshops and document analysis. The results show that the municipality has a huge potential for agriculture and improved utilisation of available arable agricultural land that still needs to be realised. The poor state of basic infrastructure for economic and social service delivery remains a key constraint to sustainable and productive agricultural land use and rural development in Mhlontlo Local Municipality. This finding tends to hamper the contributions of the rural labour force to productive agricultural enterprises as well as limiting the knowledge base of rural people. This study recommends an integrated approach to rural agricultural transformation in Mhlontlo which requires infrastructure investments with a broader scope that transcends agricultural land use developments. For example, direct agricultural infrastructural investments and activities need to be complemented by investments in social services aimed at reducing poverty and stimulating socio-economic growth and development of the local municipality.

Charles Nhemachena, James Chakwizira

Chapter 29. Agricultural Land Conversion: Application of Land Capability Classification in Land-Use Planning of Embaderho Village in Eritrea

Land capability classification has been used for sensible land reallocation and distribution for settlement purposes. A case study has been conducted to assess how much fertile agricultural land is converted to urban use between 1995 and 2003. This conversion has been assessed in terms of total as well as under each land capability class to examine whether competition between land use for agriculture and housing is leading to landlessness. Assessment is made by superimposing the maps on grid transparent papers using 1995 capability map. Land area possession per family is calculated by dividing total cropland area with total number of households in the village. Interviews and discussions with inhabitants witnessed their feelings about land conversion and subsequent impact on farmers’ possession of arable land and livelihood. The assessment demonstrated that 234.9 ha (23.7% of the highly and moderately potential cropland) has been converted to urban use, including 146.5 ha (38.5% of the capability class I land) being reallocated for settlement. Cultivable land area possession per household is reduced (1–0.35 ha) causing land fragmentation and landlessness in the village affecting the livelihood in general and specifically women-farmers-led families. Based on the present study, it has been concluded that the available land capability classification system has not been properly practiced in the reallocation and distribution of land for settlement purpose.

Tewoldemedhin D. Rustu

Chapter 30. Assessment of Land Use Planning and Development in Nigeria: Challenges and Policy Implications on Agriculture

The world is facing problems of poor land, water, and waste products management. This has attracted the international, national, and local attentions. This chapter presents a comprehensive land use plan based on the past and present land use planning and management practices in Nigeria and highlights the challenges and implications on agricultural production. It is revealed that land transformation is a common phenomenon in Nigeria. The rising land costs and accessibility to urban land has become a serious issue affecting agricultural production with over 70% of the citizens living on less than US$1 a day. The land use management has been wholly concerned with the granting of statutory right of occupancy and approval of plans to use land for different purposes without adequate monitoring of its outcomes. The lack of monitoring is attributable to a number of factors including lack of interests to adopt alternative land use systems. To create conducive environment for the present and future generations, it is essential to fundamentally rethink on land use control mechanism, policy, and action. To achieve such a favorable environment, it is prerequisite that land use laws should be enforced by the policy makers. It is also important to involve relevant stakeholders in the process of environmental planning to share their interests and opinions.

Abiodun E. Obayelu

Chapter 31. Soil Use Planning and Decelerating Crop Productivities: Policy Implications for Indian Punjab

Soil is the prime natural and economic resource of any nation. Soils are heterogeneous in composition due to difference in parent material, soil texture, physical and chemical properties, climatic conditions and occurrences on different topographic positions. Soils of the Indian Punjab have been developed on alluvium in flood plain (alluvial soils). Others are loamy, sandy, desert and kandi soils. These soils are different in their inherent soil fertilities, presenting options to cultivate various crops. The combination of major breakthrough in Mexican wheat and Filipino rice cultivars, availability of well-developed irrigation network, adequate marketing infrastructure and price support policy led to predominantly monoculture oriented rice-wheat rotation in the Indian Punjab. This has resulted in manifestation of several adverse effects on soil use efficiency and fast deceleration of crop productivities. To improve soil fertility, annually 1.3 × 10

6

t of nitrogen, 0.354 × 10

6

t of phosphorus and 0.039 × 10

6

t of potash fertilizers are added to soils. The use of chemical fertilizers in the state has risen from 0.213 × 10

6

t in 1970–1971 to 1.698 × 10

6

t in 2007–2008. Even though the soil fertility (macro- and micronutrients) is depleting continuously, calling for a pragmatic soil/land use planning for crop diversification is based on soil suitabilities in different areas of the state for particular crop(s).

Davinder K. Grover

Chapter 32. Land-Use Planning for Sustainable Development Using Geoinformatics: Policy Implications for Drylands

The land is the basic natural resource of the planet earth. Continuing population growth has definitely increased food, fuel and fodder demands, and this has put pressure on the judicious use of land resources. Therefore, proper and rational planning is essential to achieve long-term benefits from this resource. The proper planning for conservation, optimum utilisation and management of these resources is not only vital for sustenance of life but also to meet the growing needs of agriculture, expanding urbanisation, increasing industrialisation and for overall socioeconomic development of the country. The Agenda 21 ratified by over 170 nations at the Earth Summit in Rio de Janeiro in 1992 highlights that the land-use planning plays a key role in natural resource management. The science of sustainable development requires setting up of strategies based on the accurate assessment of the earth’s carrying capacity. This requires an integrated approach towards harnessing land resources after taking into account the vulnerable environmental condition. In this study, a dryland part of middle Ganga plain, known as Son-Karamnasa interfluve, in India is selected. Based on the results, alternative land-use systems and integration of livestock enterprises with the agriculture system have been suggested for land resources management. The objective of this chapter is to present a land-use plan to increase the productivity of land for sustainable development. The present study is likely to contribute required inputs to help policymakers to improve the socioeconomic and environmental conditions of the drylands.

R. B. Singh, Dilip Kumar

Chapter 33. Remote Sensing and Geographical Information as an Aid for Land Use Planning and Implications to Natural Resources Assessment: Case Study, South India

Anthropogenic changes in land use are being increasingly recognized as critical factors influencing global change. Land use is often shaped by human and socio-economic and political influences on the land. Remote sensing (RS) integrated with geographical information system (GIS) provides an effective tool for analysis of land use and land cover changes at a regional level. The geospatial technology of RS and GIS holds the potential for timely and cost-effective assessment of natural resources. These techniques have been used extensively in the tropics for generating valuable information on forest cover, vegetation type and land use changes. In the present study, RS and GIS have been used to assess land cover patterns in Pulivendula-Sanivaripalli area of south India. With this in view, an assessment has been made on some of the natural resources and environmental potential of Pulivendula-Sanivaripalli area of south India. To achieve these, three thematic maps (land use and land cover, drainage and slope) were prepared through image interpretation and limited checks. The land use-land cover pattern falls under the broad categories of agricultural land, forest land and wasteland. The agricultural land is further subdivided into dry and wet agricultural land. Forest land has been classified based on the United States Geological Survey (USGS) land use and land cover classification system, using remote sensing data as dry and wet forest land. Further, the forest land has been classified into reserve forest and wasteland vegetation. Social forestry programme includes plantations and development of pasture land; control of soil erosion by afforestation has been suggested. In the study area, most of the land (60%) is unused, and this can be used for industries and urban planning.

N. Jayaraju, J. Abdullah Khan

Chapter 34. Common Land Resources: The Present Status and Need for Their Conservation in North India

The common land resources (CLRs) as the name implies have common access to all for various economic gains. The CLRs include forests, pastures, barren land, uncultivated land other than current fallow land and cultivable wastelands. The forests provide timber and pastures support livestock. The uncultivated and barren lands support industrial and urban development. Agroforestry and social forestry are also practised. The “common access” to these resources has led to unchecked and rampant use, leading to their degradation. In general, they account for a substantial share in income, socio-economic development and sustainable livelihood of the landless people, marginal and small farmers. Over the last 50 years, the population growth, urbanization and industrialization have led to overexploitation of the resources having “common access”. The share of CLRs in the Uttar Pradesh during 1950–1951 was 34.28%; since then CLRs continue declining. Considering the declining trend of CLRs and their role in socio-economic development of the unprivileged, there is a need to manage them in a judicious way through the formulation of suitable and effective policies by the government to prevent degradation and extinction of CLRs.

Mohd Sadiq Salman, Abdul Munir

Chapter 35. Participatory Soil and Land Evaluation Mapping: An Alternative Approach to Improve Soil and Land Evaluation Information for Decision Makers

Results of soil and land evaluation survey and mapping, which were expected to be essential to rural land use and management planning, most of the time are not adequately used by their potential users and rarely reach the decision makers. This may reflect the poor communication between the main actors of the rural land use planning process and inappropriate language of the presented results. When following traditional methods, there is a risk that questions may be answered that have no relevance and/or those questions may not be answered properly according to the community expectation. Therefore, it is important to change the strategies of communication and language of the results to make information more useful to the decision makers. In this context, the objective of this work was to test a participatory soil survey and land evaluation methodology to make the information more useful and consequently more used by the decision makers. This work shows the results obtained up to now in Barra Bonita municipality, Santa Catarina State, southern Brazil. The study started with meetings, interviews and questionnaires with local community, and the main demands for information raised were the need for area expansion and management improvement of pastures for milk production. But, instead of giving them information showing soil types with technical language and a general information about land evaluation, the presented information shows what they want to know, namely, spatial location of potential new areas for pasture, what pasture type is better for different conditions and what management is recommended for each area. In the final stage of the study, participants positively evaluated the presented information.

Ivan Luiz Z. Bacic, Juniele R. Pivetta, Roberta P. Martins

Chapter 36. Land Suitability Assessment of the Proposed Uranium Mining Area in North-East Botswana

Land suitability assessment of the proposed uranium mining site was made to mitigate the possible environmental hazards arising from its potential use. The FAO framework of land evaluation and guidelines for land use planning were employed to assess the land suitability for arable, pasture/grazing and forestry uses. Typical soil textures are sandy loam to sandy clay loam, generally characterized by high base saturation and good fertility. The soils are deep enough for plant growth. Water-holding capacities are favourable for most of the agronomic crops and pastures. The mining area is assessed as marginally to moderately suitable for arable farming and grazing. Poor drainage, soil salinity and rainfall are the limiting factors for arable crops, whilst poor quality of vegetation species and rainfall are the major constraints to pasture and grazing. The area is marginally suitable to forestry due to rainfall being the main constraint. Overall, the area is suitable for grazing/pastures and arable farming, with few pockets suitable for forestry use.

Oagile Dikinya

Chapter 37. Sustainable Development and Management Policies for Soil and Water Conservation in Egypt

Sustainable development and management policies for soil and water conservation in Egypt pose a dilemma to develop irrigation strategies for irrigated agriculture to reduce negative environmental impacts, an inevitable consequence of irrigation. For proper irrigation management, it is necessary to (1) improve the accuracy of soil water balance components to calculate a reliable estimate of the leaching fraction, (2) estimate the leaching requirements and add to irrigation requirement, (3) consider the water distribution uniformity to decide which part of the field should receive at least the leaching fraction for salinity control, (4) take into account that leaching salts periodically is more practical than every irrigation, (5) consider that there is no need to increase irrigation frequency to control salt concentration except for drip irrigation, and (6) monitor the root zone salinity, especially prior to periodic leaching. Adoption of appropriate irrigation system for specific soil types is necessary, e.g. sprinkler system is well adapted to sandy and loamy soils but less so to heavy or clayey soils. The drip or trickle irrigation system is better adapted to loamy or clayey soils and release water through many emitters at rate of 2–4 l h

−1

. Moreover, drip irrigation provides a greater opportunity for using saline water. The policy of the Egyptian Government is to use drainage water up to EC of 4.5 dS m

−1

after blending with fresh Nile water and to assure that the resultant EC of the blended water do not exceed 1.0 dS m

−1

.

A. Z. El Bably, S. A. Abd El-Hafez

New Trends in Land Degradation and Desertification

Frontmatter

Chapter 38. New Trends in Land Degradation and Desertification Research and the Role of the Association DesertNet International in Sharing Knowledge and Promoting Sustainable Land Management

Efforts of the international and national organisations to halt or reverse land degradation have produced mixed results. Problems are much accentuated in the drylands due to their natural fragility coupled with human-induced pressures and further exacerbated when land degradation is combined with naturally occurring drought. The recent terminology adopted by the United Nations Convention to Combat Desertification (UNCCD) involves desertification, land degradation and drought (DLDD). However, confusion still exists to distinct between them, and this hampers actions from decision-makers as often maps and databases do not make a clear distinction between the potential risks or status of degradation. Soil information could remedy these shortcomings, but soil information must be supported by new surveys to update obsolete soil data. The recommendations of the First Scientific Conference of the Committee on Science and Technology (CST) of the UNCCD held at COP9 in Buenos Aires, Argentina, in September 2009 suggest that desertification research and mitigation should be based on ten priority areas, and the trend is to support sustainable land management rather than focusing only on combating land degradation. The positive outcomes of this paradigm shift emphasise the role of soil as a nonrenewable resource and endorse a biophysical and socio-economic ecosystem-based approach for assessment and monitoring. The Association DesertNet International (DNI) formed on the grounds of the former European DesertNet is aiming to translate scientific knowledge for improved land management of the drylands. As a non-governmental scientific entity, DNI is open to all of them who have interest in land degradation/desertification research.

Pandi Zdruli

Chapter 39. Land-Use Planning for Controlling Land Degradation in Kuwait

Several land degradation indicators have been recognized in Kuwait; these are soil loss by wind and/or water; soil crusting, sealing, and compaction; soil contamination by oil; soil salinization; deterioration of vegetation cover and its biodiversity; and hydrological degradation. Aeolian processes, as manifested by soil deflation, drifting sand, and migrating dunes, may be considered as one of the primary causes of soil degradation in Kuwait. The present status of land degradation as reflected by the severity of degradation of vegetation cover, soil erosion/deflation, and hydrological drought has been assessed based on visual comparison between data recorded in the early 1980s and recent field surveys (early 2010). It has been concluded that the northwestern and southern parts of Kuwait are severely degraded. Anthropogenic activities (off-road vehicle traffic, excessive grazing, camping, and quarrying) as well as military operations (Gulf Wars and present defense structures) are the main causes of land degradation in Kuwait. However, aeolian processes, nature of surface sediments (soil type), and climatic conditions play a significant role. It was also recognized that the sandy soils (Torripsamments) that cover most of the southern part of Kuwait are the most vulnerable to aeolian processes, particularly soil loss by deflation. Hence, mitigation measures for the maintenance of Kuwait desert ecosystem are recommended.

Fikry I. Khalaf, Jasem Al-Awadhi, Raafat F. Misak

Chapter 40. Methodological Approach to Estimate In-Site Costs of Desertification When Empirical Data Are Not Available

This chapter addresses the issue of economic losses due to soil erosion and discusses some well-known methodologies used since the 1990s by different authors in the USA and Europe. Issues related to the reliability of data are analyzed, and the consistency of the basic assumptions in the literature is questioned. A new approach is used considering the lack of empirical and reliable data in order to determine the economic losses of land degradation. The Universal Soil Loss Equation is applied to estimate the economic losses in 11 Latin American countries. Estimations of the GNP losses are also presented. Finally, it is pointed out that the importance of the economic losses is not proportional to the political attention governments have been giving to the problem.

Heitor Matallo Junior

Chapter 41. Managing the Hazards of Drought and Shifting Sands in Dry Lands: The Case Study of Kuwait

Dry lands cover about 41% of the global terrestrial areas. These are characterized by low average annual rainfall and large variations. Drought is a serious natural hazard in Kuwait and its adjacent countries. During the last four decades, Kuwait experienced a number of dry seasons with rainfall below average (<110 mm year

−1

). During 2007–2008 and 2008–2009 dry seasons, total rainfall of 35 and 65 mm was recorded, respectively. The consequences of the drought seasons were the massive soil losses (750–1,000 m

3

ha

−1

in the west Managish area in July 2008); severe sand encroachment even in areas protected for decades, e.g., KISR experimental station at Kabd; relatively longer period of sand and dust storms (May–September 2008 and July–August 2009); and depletion of soil moisture and dryness of natural vegetation.

Sustainable land-use planning in Kuwait is the first defensive step to mitigate the consequences of drought and to reduce land degradation. In the past 15 years, significant changes in land use were observed in Kuwait. Some of these changes have positive and others have negative ecological and environmental impacts. Establishment of the buffer zone (15 km wide and >200 km long) between Iraq and Kuwait in 1993–1994 enhanced the vegetation cover and improved biodiversity and soil conditions, while border trenches (3 m deep, 5 m wide, and hundreds of kilometers long) and the construction of bund walls (2–3 m high, 3–5 m wide, and hundreds of kilometers long) have negatively affected surface water and natural vegetation. It is visualized that in Kuwait sustainable measures to mitigate the consequences of drought are not well adopted. Based on the vast KISR experience in managing dry lands, four programs are proposed to manage the hazards of drought in Kuwait. These are watershed management and restoration, mitigating hydrological drought, managing the hazards of shifting sands, and setting up sustainable land-use plans. The main objective of this study was to adopt integrated approach to mitigate drought in Kuwait. To achieve the objective, intensive fieldwork including experiments and surveys accompanied by analyses and interpretation of remote sensing data were carried out and reported in this chapter.

Raafat F. Misak, Fikry I. Khalaf, Samira A. S. Omar

Chapter 42. Determining Degraded Soils of Southern Kazakhstan Through Assessing Stability of Soil Aggregates

Degradation of irrigated soils is often the consequence of changes in physical and chemical properties. Such changes are reflected in the loss of soil structure, dispersion of soil particles, compaction, reduction in permeability, and hydraulic conductivity. These processes are widespread on the irrigated soils in the midstream of Syrdarya and Zarafshan river basins of Central Asia. The Arys-Turkestan Canal (ATC) command area in the southern Kazakhstan is a typical example of degraded irrigated soils. Cotton crops cultivated on these soils have suboptimal aboveground growth and weak root systems that drastically reduce yields. Determining the degradation level of the irrigated soils is important in assisting the farmers to select appropriate soil management strategies and reduce the risk of accelerating degradation. This study focuses on identifying the degree of degradation by determining the stability of soil aggregates. Water-stable aggregates were analyzed of topsoil from the ATC zone under four contrasting management practices: undisturbed virgin soil, productive irrigated soil, low-productive degraded soil, and salt-affected abandoned soil. The results of these studies clearly show a trend in a reduction in the quantity of the stable macroaggregates on the degraded soils. Among a range of different aggregate stability indices, the stable macroaggregate index (SMAI) was found to be the most suitable to differentiate highly degraded soils. The SMAI values of less than 10% are found to be indicative of soils having poor physical properties. Sensitivity analyses found that the SMAI is most sensitive to the changes in the following soil properties: quantity of particles <1-μm size, electrical conductivity of the soil, organic matter, and gypsum content.

Akmal Karimov, A. Noble, R. Kurbantoev, N. Salieva

Modeling of Soil and Groundwater Contamination

Frontmatter

Chapter 43. Application of a Screening Model to Evaluate Pesticide Contamination in Soil and Groundwater for Sustainable Agriculture in Oman

In the recent years, agricultural activities in Oman have been increased significantly that has increased the use of pesticides. Consequently, soil and groundwater quality is likely to deteriorate. This chapter presents prediction of pesticide movement through the unsaturated zone to groundwater. This will help the decision makers in assessing the likelihood of soil and groundwater contamination in Oman under various land use practices. A model (PESTAN) based on the analytical solution of 1-D advective-dispersive-reactive transport equation is used to estimate the vertical migration of the dissolved organic solutes as well as for conducting initial screening assessment of the potential for contamination of soil and groundwater. PESTAN calculates the movement of organic chemicals with a linear isotherm, first-order degradation, and hydrodynamic dispersion. Input data include the following: soil, chemical, and management practice parameters. Data on Omani soil, climatic, and irrigation practices as well as chemical parameters of most common pesticides used are required for modeling. Reliable assumptions are made to compensate for missing data. The main objective was to model the top ten pesticides used in Oman for 5 years to calculate the time each particular pesticide would take to reach the water table that is estimated to be at 10-m underground surface. Three scenarios were developed, after selecting three variables which mainly contribute to pesticides’ fate: recharge, soil texture, and application rate of pesticides. For each variable, maximum and minimum values were modeled to be compared with a base run describing the recommended conditions. The results suggest that the more the recharge and application rates, the faster the pesticides reach groundwater. In coarse-textured soil, the pesticides penetrate faster through the soil profile. Overall, the simulations demonstrated that none of the ten pesticides is reaching the water table to a depth of 10 m within 5 years by assuming a single application, where application frequency is concerned. Reducing irrigation amount and increasing the organic matter content of the soil will help reduce groundwater contamination.

Basma Nasser Al-Shidhani, Mushtaque Ahmed, Salem Al-Jabri, Farid Talukder

Chapter 44. Modelling of Soil Contamination and its Remediation by In-Situ Solvent Flushing

The consequence of industrialization and other development activities have led to serious degradation of land and water quality. Its remediation has become an important necessity in this scenario. To overcome this issue, it is essential to understand the nature of contaminant transport and their adsorption and desorption substance characteristics. In this study, both organic and inorganic contaminants have been considered, and their movement through the soil together with adsorption and desorption characteristics as well as chemical/biochemical degradation has been investigated. The transport has been described using a set of equations numerically solved with different boundary conditions to represent several scenarios experienced in several cases in the arid environment. The modelling has been confined to one dimension assuming the soil is homogeneous. Contaminant transport may be visualised in many ways; however, in this study, two specific cases are considered. First case is the movement of leachate from soil waste dumping to ground, where toxic organic and inorganic chemicals were also dumped. The second case is the large-scale spillage of some toxic chemicals/oil/chlorinated solvents/non-chlorinated solvents on the soil and their subsequent movement through the soil. There can be several variations of these scenarios. In this chapter, variation with respect to rainfall in the area followed by dry seasons is considered. There is no single technique universally applicable for all contaminated sites. This chapter presents an analysis of the site restoration techniques that may be employed in a variety of contaminated site cleanup programmes.

Anwar A. Khan

Innovations in Research, Development, Education and Extension

Frontmatter

Chapter 45. Sharing Information to Accelerate Implementation of Reclamation and Improvement of Degraded Lands: WASWAC Experience

Degraded lands are lands that have become inferior in quality, essentially in terms of crop productivity or in providing environmental services. Previously, it was the matter of land conservation and improvement that occupied researchers’ mind – but since 20–30 years ago, the interest had shifted to the point that people pay more interest to the causes of degradation and how to correct them. It thus seems to be a decent way to implement any program concerning soil or land. For the research part, there have been many projects and programs that do research on land degradation today, the executors of which are universities, government agencies, research institutions, etc. From doing research, there are a lot of results that are produced each year. The next step is to present the research findings that researchers go to attend conference at various venues or publish in peer-reviewed scientific journals. There are several series of meetings, that is, ICLD, ISCO, COMLAND, ESSC, WASWAC, IECA, SWCS, and many other national societies of soil and water conservation. For the implementation part, the noted work to combat land degradation commenced in USA by the agency called Soil Conservation Service (SCS), which later became Natural Resources Conservation Service (NRCS). This agency is a part of the US Department of Agriculture (USDA). Many visitors from abroad go to learn soil conservation techniques and take back to apply in their own countries – often with certain degrees of modification.

Samran Sombatpanit

Chapter 46. Innovations in Soil Chemical Analyses: New ECs and Total Salts Relationship for Abu Dhabi Emirate Soils

Soil analysis is important to understand composition of soils for many reasons including developing soil management options for sustainable agricultural activities. There exists a relationship between total soluble salts (meq l

−1

) and ECs (dS m

−1

) developed in 1954 and published in the USDA Handbook 60. In the present study, an attempt has been made to correlate total soluble salts and ECs values from a range of soils from Abu Dhabi Emirate to test the validity of USDA relationship to local soils. The USDA ratios (TSS/ECs) of 10 and 16 exist for ECs 1 and 200 dS m

−1

, respectively (

R

2

= 0.9577). Whereas TSS/ECs ratio from Abu Dhabi Emirate soils was found to be 10 and 11.38 for ECs 1 and 200 dS m

−1

, respectively, and for ECs 500 dS m

−1

a ratio of 12 was found (

R

2

= 0.9711), the USDA does not present such a ratio for ECs more than 200 dS m

−1

. The present study has rejected the hypothesis that same relationship exists between TSS/ECs on soils of Abu Dhabi Emirate as that of USDA and, therefore, this relationship cannot be used for Abu Dhabi Emirate conditions. This chapter presents a new ratio for Abu Dhabi soils to avoid misinterpretation of soil analytical data for quality assurance (QA) purposes and to formulate soil management options. The newly developed relationship was validated by measuring sodium adsorption ratio (SAR) by various methods, that is, using Na derived by difference between TSS and Ca + Mg and through measured Na and Ca + Mg values from Abu Dhabi Soil Survey. The SAR calculated by using Na derived from newly developed relationship fits close to the SAR values from actually measured Na and Ca + Mg contents; these SAR values deviate to those measured from USSL and USDA relationships. In the light of present finding, it is recommended that other regions where soil and environmental conditions are similar to Abu Dhabi Emirate, a similar relationship most suited to their local conditions should be developed or the results to be correlated with that established from Abu Dhabi soils for validation.

Shabbir A. Shahid, Mahmoud A. Abdelfattah, Henda Mahmoudi

Chapter 47. Quality Assurance Standards: USDA Perspective of the Extensive Soil Survey of Abu Dhabi Emirate

Soil scientists from USDA-Natural Resources Conservation Service were invited by the International Center for Biosaline Agriculture (ICBA) and the Environment Agency-Abu Dhabi (EAD) to participate in a quality assurance review of the extensive soil survey of Abu Dhabi. The review was of interest to USDA not only due to the application of US soil survey mapping and classification standards but the emphasis on developing soils within the emirate into useful and productive agricultural areas. Meetings were conducted with scientists of ICBA and EAD and the soil survey management team of GRM International (Australian mapping contractor) to review various aspects of soil mapping, soil survey documentation, and day-to-day operational procedures. Field visits included examination of representative polygons of preselected map units with on-site investigation by backhoe and hand dug pits traversing a widely diverse set of landscapes and landforms across several regions of the Abu Dhabi Emirate. Processes for soil pedon examination, recording of soil properties, classification of soils, mapping procedures, and determination of map unit composition were evaluated. Additional methods used within the USA were presented for consideration when conducting future soil surveys. Laboratory procedures used in the analysis of soil samples were based primarily on USDA-NRCS methods, and derivations unique to the Abu Dhabi soil survey were reviewed. In support of ongoing cooperative efforts between the agencies of USDA, ICBA, and EAD, soil samples were collected for detailed analysis in an effort to develop new methodology for identification and quantification of anhydrite, as well as elucidate the mechanism and controlling factors for the formation of this mineral in soils of the region. Field and laboratory methods, standards, and procedures implemented by the project team (both ICBA/EAD and GRM) with their high level of technical skills, knowledge, and experience have ultimately yielded an array of high-quality soil survey products greatly enhancing the wise use of one of the region’s most precious natural resources—its soil.

John A. Kelley, Michael A. Wilson, Mahmoud A. Abdelfattah, Shabbir A. Shahid

Chapter 48. The Role of Mycorrhiza in the Reclamation of Degraded Lands in Arid Environments

Land disturbance and degradation is recognized as one of the most important environmental problems worldwide caused by many factors like human activities and adverse climatic factors like that occurred in most parts of the arid and semiarid regions (e.g., the Middle East and Arabian Peninsula). In the arid environments, land degradation is mainly caused by wind erosion and salinization with loss of productive surface soil and loss of vegetation as primary indicators. In these regions, soil conservation and rehabilitation of degraded lands are essential for sustainable agriculture and improvement of dry land ecosystem. Revegetation is one of the most effective means to control soil degradation and to rehabilitate degraded lands. However, in arid environments, low rainfall, harsh climatic conditions, and frequent droughts are major limitations for natural rehabilitation. There is a general consensus that biotechnology can be a valuable tool to mitigate water scarcity and to improve quality of degraded lands. Microbial technology, e.g., use of mycorrhizal fungi, has been considered a valuable tool in the rehabilitation of disturbed and degraded lands. Mycorrhizal fungi play a crucial role in enhancing plant growth and survival through enhancing plant nutrient uptake, water relations, ecosystem establishment, plant diversity, and productivity of plants. Mycorrhiza also protects plants against root pathogens and abiotic stresses such as drought and salinity and improves soil structure by enhancing soil aggregation and water-holding capacity. This chapter provides an insight into how mycorrhizal fungi might play a role in reclamation and revegetation of degraded lands in arid regions.

Ghazi N. Al-Karaki

Chapter 49. Preliminary Interpretation of Environmental Isotope Data in the Ain El Atti Area (Tafilalet)

Present study on the sustainable use of saline land and saline groundwater for agricultural production has been conducted in the pre-Saharian area of Ain El Atti through the application of environmental isotopes supported by the hydrochemistry. In the study area, a network of 20 water points has been the focus of the isotope analysis (δ

18

O, δ

2

H,

3

H and

14

C) and physical chemistry. The samples were collected once every 3 months from artesian groundwater of “the Infracenomanian” (4), the Turonian (4), the Senonian (1) and the Quaternary aquifer (5) and from the precipitation of the years 2001, 2002 and 2003. The results show that (i) the stable isotope from the Infracenomanian is very poor and they are without tritium, confirming the fact that this aquifer is confined and it is not evaporated. Its strong salinity is due to the dissolution and the lixiviation of the geological formation; (ii) the Turonian, the Senonian and the Quaternary aquifers are not confined, and their stable isotope contents more or less important as the tritium, signifying that they receive recent recharge. The first one is affected by the artesian well and it is not evaporated and it has high salinity. The second and the third one are not affected by the artesian well, but the influence of the precipitation and the flood is clear. Their groundwater is not evaporated and their salinity is moderate; (iii) however, the Ziz surface water isotopic elements are rich, signifying an actual recharge. Its water is highly evaporated and its salinity is variable.

Mohamed Aoubouazza, Willibad Stichler, Piotr Maloszewski

Chapter 50. Use of Lombrica to Enhance Soil Fertility for Crop Production in Madagascar

Eighty percent of Malagasy population are peasants and practise agriculture. Continuing population growth increases food demand, and to achieve food demand, there is a need to find ways for rational use and management of soil resources for better agriculture production. This requires more soils to be brought into cultivation; however, the country lacks sufficient cultivable soils to meet food demand. The Malagasy government strongly supports agriculture development and encourages the farmers to find new soils for cultivation and crop diversification. In order to bring more soils into cultivation and to improve crop productivity, farmers need more fertilizers to offset nutrient requirement of crops and to improve soil fertility status. As per local experience, we believe that the use of ‘lombricompost’ fertilizer is essential for Malagasy farmers. Owing to the high price of chemical fertilizers and its impact on soils, we found the ‘lombricompost’ a beneficial fertilizer with affordable price and easy to produce locally. Besides the exploitation of ‘lombricus worm’, it generates income and contributes enormously to the amelioration and protection of the environment. In this chapter, the benefits of using lombrica to farmer’s daily work, daily life and environment are discussed.

Razafindravoniarisoa Euphrasie

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