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2008 | Buch

Eutrophication in the Baltic Sea

Present Situation, Nutrient Transport Processes, Remedial Strategies

verfasst von: Lars Håkanson, Andreas C. Bryhn

Verlag: Springer Berlin Heidelberg

Buchreihe: Environmental Science and Engineering


Über dieses Buch

For many years the reduction of eutrophication in the Baltic Sea has been a hot issue for mass-media, science, political parties and environmental action groups with manifold implications related to fisheries (will the Baltic cod survive?), sustainable coastal development (have billions of Euros been wasted on nitrogen reductions?), ecotoxicology (can we safely eat Baltic fish?). This book takes a holistic process-based ecosystem perspective on the eutrophication in the Baltic Sea, with a focus on the factors regulating how the system would respond to changes in nutrient loading. This includes a very special process for the Baltic Sea: land uplift. After being depressed by the glacial ice, the land is now slowly rising adding vast amounts of previously deposited nutrients and clay particles to the system. 110,000 to 140,000 tons of phosphorus per year are added to the system from land uplift, in comparison to the 30,000 tons of phosphorus per year from rivers.


Chapter 1. Introduction, Background and Aim
The situation in the Baltic Sea, and especially in the Baltic Proper, is discussed very intensively in the media, at environmental authorities at local, regional and national levels, and certainly among the general public and scientists.
Lars Håkanson, Andreas C. Bryhn
Chapter 2. Basic Information on the Baltic Sea
Empirical data ultimately form the basis for most environmental studies. As Goethe once eloquently put it: “Grey, dear friend, is all theory, and green the golden tree of life”. The focus of this chapter is on empirical data and empirical models. Extensive databases on the conditions in the Baltic Sea and other aquatic systems have been “data-mined” and in this chapter we will present results showing variations of target variables related to the eutrophication in the Baltic Sea (nutrient concentrations, chlorophyll-a concentrations and Secchi depths) and trend analyses to see if therehave been any changes in these variables in the Baltic Sea.
Lars Håkanson, Andreas C. Bryhn
Chapter 3. Water Exchange and Water Transport in the Baltic Sea
It is not possible to quantify, understand and predict changes in concentrations of chemical substances (nutrients, metals, radionuclides or organic toxins) in aquatic systems, e.g., related to costly remedial measures, without process-based massbalance calculations. This is true at all temporal and spatial scales and for all types of aquatic systems and for all types of substances. The quantification of water fluxes and retention rates are fundamental in mass-balances for nutrients (eutrophication) and this has been clear since Vollenweider presented the first loading models for phosphorus in lakes in 1968 (Vollenweider, 1968).
Lars Håkanson, Andreas C. Bryhn
Chapter 4. Empirical Data and Models on Nutrients and Bioindicators in the Baltic Sea
The question about “limiting” nutrient is certainly central in aquatic ecology and has been treated in numerous papers and textbooks (e.g., Dillon and Rigler, 1974; Smith, 1979; Riley and Prepas, 1985; Howarth, 1988; Hecky and Kilham, 1988; Evans et al., 1996; Wetzel, 2001; Geider and La Roche, 2002; Labry et al., 2002; Newton et al., 2003; Smith et al., 2006; Håkanson and Bryhn, 2008a). Figure 4.1 illustrates key questions related to the concept of “limiting” nutrient and the nitrogen/ phosphorus dilemma.
Lars Håkanson, Andreas C. Bryhn
Chapter 5. Nutrient Dynamics in the Baltic Sea
This chapter can in many ways be regarded as the core part of this book. It describes the CoastMab-model and how the model can be used to quantify the phosphorus fluxes regulating and describing the response of the Baltic Sea system to the phosphorus loading to the system. The model also predicts howmuch phosphorus there is in particulate form, the only form that can settle out due to gravity, and how much of the phosphorus that appears in dissolved form, the only form available for biouptake by phytoplankton.
Lars Håkanson, Andreas C. Bryhn
Chapter 6. Strategies for Remediation
It is very difficult – and certainly very important for Baltic Sea management – to try to set the costs to suggested remedial measures for the Baltic Sea (or for any aquatic system suffering from increased anthropogenic nutrient loading). If this is not done, very costly mistakes can continue to be suggested and implemented.We will give a few examples for the Baltic Sea in this introduction.
Lars Håkanson, Andreas C. Bryhn
Eutrophication in the Baltic Sea
verfasst von
Lars Håkanson
Andreas C. Bryhn
Springer Berlin Heidelberg
Electronic ISBN
Print ISBN