The impact of utilization of palm products on the population structure of the vegetable ivory palm (Hyphaene petersiana, arecaceae) in North-Central Namibia

Abstract

Indigenous trees fulfil many subsistence and economic needs in north-central Namibia.Hyphaene petersiana provides a range of products which contribute to most aspects of people’s livelihoods. Of particular importance is its income-generating capacity through the use of palm leaves for basket production and the sale of liquor distilled from the fruits. This study investigates the population structure ofHyphaene petersiana in two areas of different human and livestock densities. Data were recorded for height class distribution, basal diameter of mature, stemmed individuals and sex ratios. These parameters of population structure indicate a reduction in the recruitment of mature palms and an increase in single-stemmed, vegetatively reproduced palm suckers of the smallest size class (0.5 m). This trend is more pronounced in the site with greater human and livestock population densities. It appears to be related to high recorded levels of browsing by livestock of juvenile, unstemmed palms, despite the unpalatability of palm leaves. This acts to prevent recruitment into larger size classes and increase the compensatory growth of palm suckers, the latter being enhanced due to reduced competition through the prior removal by grazing animals of grasses and other herbaceous species. Accompanying this heavy pressure on juvenile palms are destructive uses of mature, stemmed palms, including their felling for construction purposes and tapping for palm wine. With regional human population increase, exacerbated by a recent trend to privatise land and raise pressure on remaining communal resources, it is possible that these destructive uses of mature palms will increase to unsustainable levels. Concern is thus expressed in this study regarding the long-term viability ofHyphaene petersiana populatiops in this area.

Résumé

As árvores indigenas satisfazem muitas das necessidades de subsistência das populacoes de Owambo. A Hyphaene petersiana fornece uma gama de productos que contribuem em muitos aspectos para o sustento das gentes daquela regiao. Cita-se em particular o seu papel na criação de rendimento atraves do uso dasfolhas da palmeira na confecção de cestos e da utilização dos frutos no fabrico de ‘olambika’ (aguardente), produtos que sao depois vendidos. Estas duas actividades sao desempenhadas quase exclusivamente por mulheres. Neste estudo manifesta-se preocupação em relação às modiflcaçoes operadas na população deH. petersiana desta regiao. A renovaçao das palmeiras é reduzida pelo pastar intensivo de rebanhos que comem os rebentos de palmeira. A isto se junta um aumento na utilização destrutiva das palmeiras maduras e de outras espécies de árvores. A exacerbar este processo cita-se a tendência recente para a privatização de terras anteriormente exploradas colectivamente. Isto deu origem a um aumento na exploração das restantes terra comunais que está a causar o colapso dos direitos tradicionais ao usufruto dos recursos vegetais.

Omiti dhomoshitopolwa ohadhi gwanitha po oompumbwe odhidji dhopamahupilo gaakalimo yomOwambo. Omuti gwendhinaHyphaene petersiana (omulunga) ohagu eta po iilikolomwa oyindji mbyoka hayi kwathele moompumbwe odhindji dhomonkalamwenyo yaantu. Omuti nguka agwa simana unene sho gahu etapo po eliko tali zi melongitho lyoombale mokutunga oontungwa, iimbamba, omashungu nuuyanambale, nokelanditho lyolambika ndjoka hayi zi moondunga. Iilikolomwa ayihe ya tumbulwa pombanda ohayi etwa po konyala kaakiintu ashike. Moshinyolwa shika omunyoli ota holola uumbanda tau etwa po komalunduluko ogendji tagi inyenge moshitopolwa ga guma omuti ngukaH. petersiana (omulunga). Oludhi nduka otalu shonopala unene sho iiyale hayi liwa po kiimuna manga yi li iishona. Omiti ndhika, osho wo dhilwe ndhoka hadhi longithwa momauhupilo otadhi shonopala neendelelo oshoka odha tamekwa okulongithwa komikalo dhilwe dhi Hi, she etwa po keshonopalo lyomaludhi gomiti dhilwe. Omukalo omupe moshitopolwa gwokuninga evi lyaayehe lyopaumwene otagu endeleleke eshonopalo lyomiti ndhika. Iitopolwa yaayehe oya shonopalekwa nevi lyaayehe otali longithwa sha pitilila tashifala sigo okengushukuluko lyevi. [OSHIWAMBO]