We made a complete survey of all the extant populations in Djibouti and to collect samples for genetic analysis with a view conserving the palm for the future.
Our survey revealed that there were a total of 314 adults, 20 juveniles, 134 rosettes, 210 small rosettes (more than 6 leaves) and 465 seedlings (<3 leaves) living in the Bankouale area of Djibouti. These are distributed unequally amongst three valley systems. 65% of the adults, 85% of the juveniles, 75% of the rosettes, 76% of the small rosettes, and 93 % of the seedlings were found in the Bankouale valley.
Coastal and freshwater ecosystems are deteriorating in many areas and at a faster rate than any other ecosystem. Such changes are caused by intertwined factors, making it difficult to identify the problems early on. While progress in integrating these various factors in managing water and ecosystems has been made in some places, the majority of the world and its inhabitants increasingly suffers from a lack of priority given to environmental protection.
Resource Type: ReportsThe ability of coral reefs to survive in a globally-warming world may crucially depend on the levels of pollution to which they are exposed, new findings indicate.
Scientists studying reefs that were bleached in the late 1990s by high surface sea temperatures have found a link between recovery rates and the levels of contamination entering coastal waters from developments on the land.
Resource Type: ReportsGeographical range is considered a good predictor of the levels of isozyme variation in plants. Widespread species, often consisting of historically larger and more continuous populations, maintain higher polymorphism and are less affected by drift, which tends to erode genetic variation in more geographically restricted species. However, widespread species occurring in small and disjunct populations may not fit this pattern. In this study we examined genetic variation in Pilgerodendron uviferum, a conifer endemic to temperate forests of southern South America.
Resource Type: Journal PapersUNEP-WCMC produces reports for a number of fora including CITES, the European Commission and the Convention on the Conservation of Migratory Species of Wild Animals (CMS). Recent examples of these reports can be downloaded here in PDF format.
Resource Type: ReportsStipitate hydnoid ('tooth') fungi are considered to be threatened throughout much of central and northern Europe. In response to concern about the status of these fungi in the UK, a Biodiversity Action Plan has been developed for 14 species in this group. As a first step towards implementation of this plan, a number of surveys have been initiated, to determine the current status and distribution of hydnoid fungi. An overview of the results of these surveys is described. A series of distribution maps are presented, based on a compilation of early records and the results of a recent field survey in Scottish coniferous forests. The difficulties of interpreting early records are discussed, with particular reference to the taxonomie confusion that has surrounded this group of fungi. Although available data provide little evidence for decline of hydnoid fungi, a number of species display very restricted distributions within Scotland. The recent discovery of several species new to Britain emphasises the need for further field surveys to define the current status of these fungi with greater accuracy.
Resource Type: Journal PapersThe effects of Pleistocene glaciations on the genetic characteristics of the most austral conifer in the world, Pilgerodendron uviferum, were analysed with specific reference to the hypothesis that the species persisted locally in ice-free areas in temperate South America.
Results indicated that Pilgerodendron populations are highly monomorphic, probably reflecting past population bottlenecks and reduced gene flow. Southernmost populations tend to be the least genetically variable and were therefore probably more affected by glacial activity than northern ones. Populations located outside ice limits seem to have been isolated during the glacial period. The presence of centres of genetic diversity, together with the lack of a significant correlation between genetic and geographical distances and the absence of geographical patterns of allelic frequencies at most analysed alleles, may indicate that Pilgerodendron did not advance southward after the last glaciation from a unique northern refugium, but spread from several surviving populations in ice-free areas in Patagonia instead.
Resource Type: Journal PapersThe forests of eastern Tanzania are a globally important biodiversity hotspot. In this study 361 eastern Tanzanian restricted range forest tree taxa were assessed. Of these taxa, 223 occurred in the Eastern Arc, 150 in Coastal forests, 17 in Northern forests and 21 in the Lake Nyasa forests. The majority of the taxa had restricted elevational ranges with 76.3 occurring in no more than two 200 m elevational bands out of a total potential elevation range of 3000 m. The majority of the taxa occupied a small area in the eastern Tanzanian forests, with 201 taxa being only found at a few sites. In determining priority areas for conservation, selection of taxon definitions can have important effects. For example, tree size varies with elevation, so if only large trees are used then site selection will be biased towards particular areas.
Resource Type: Journal PapersThis study demonstrates the utility of carbon isotope discrimination in describing genetic adaptation to arid environments, although it is probably most useful in detecting differentiation when the strategy of the species under investigation is to increase water use efficiency, rather than drought-avoidance. The results suggest that populations on the eastern and western sides of the Andes should be treated as separate management units for the purposes of conserving the genetic resource of this species.
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