The 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 PapersThe areas of the ocean that lie beyond national jurisdiction limits, also called the high seas, are vulnerable to human activities and currently underrepresented when compared to terrestrial and nearshore1 marine environments under protection. Thus, there is a growing movement among the conservation community to increase measures, such as marine protected areas, that can ensure protection of the largely undiscovered but important biodiversity of the high seas.
Resource Type: ReportsThis summary document outlines the need for spatial data on tree species as a tool for conservation action. It introduces plans for a tree species mapping programme that will build on the forest mapping information management expertise of UNEP-WCMC. A Global Tree Conservation Atlas will be one of the main outputs of the Global Trees Campaign. The Campaign focuses on trees as flagship species for conservation of ecosystems and landscapes, and enables local people to carry out rescue and sustainable use operations. Working in partnership with organizations around the globe, the Global Trees Campaign aims to save the world's most threatened tree species and their habitats through information, conservation and wise use.
Resource Type: ReportsThis 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.
Resource Type: Journal PapersTropical trees in the genus Aquilaria Lam. are the principal source of gaharu, one of the most valuable forest products traded internationally. Although these species are the focus of increasing conservation concern, information on their status and distribution is lacking. Information from herbarium accessions, a national forest inventory (NFI), field surveys and gaharu traders was used to assess the distribution of Aquilaria species in Indonesia, indicating population concentrations in Sumatra and eastern Kalimantan.
Given current deforestation rates, these data suggest that all Aquilaria species in Indonesia classify as Vulnerable according to the IUCN Red List criteria.
Resource Type: Journal PapersThe threatened Chilean conifer Podocarpus salignus D. Don is currently the focus of ex situ conservation eorts being undertaken by the Conifer Conservation Programme of the Royal Botanic Garden Edinburgh. To assess variation within in and ex situ populations of the species, leaf material collected from four wild populations was analysed by random amplified polymorphic DNA (RAPD).
RAPD was found to be an effective tool for assessing the genetic structure of P. salignus, for providing a guide to future germplasm-sampling strategies, and for hybrid identification. Implications for genetic conservation of the species and the role of ex situ approaches are discussed.
Resource Type: Journal PapersSmall local hunting communities in Siberia are very distant from any governmental control. Hunted waterbird species, including globally and regionally threatened species, rely for their well-being on the self regulation of remote hunting communities. Interviewed hunters showed a profound knowledge of Baikal Teal, its population status, and the causes of their past decline. Whether the knowledge is shared by other communities in the region and beyond in Northern Siberia needs verification.
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Fagus grandifolia var. mexicana (Mexican beech) is limited to about 10 populations (2-35 ha) in the Sierra Madre Oriental, Mexico. The objectives were to assess the current status and distribution of beech by surveying five sites. Species richness varied between three to 27 tree species in the canopy, and from nine to 29 species in the understorey. Basal area of trees greater than or equal to 5 cm dbh varied between 27.87 and 70.98 m2 ha-1, and density from 370 to 1290 individual ha-1. Beech represented 22-99.6 of total basal area, and 6.8-83.3 of total density. Beech dominance varied from monodominant to codominance with Carpinus caroliniana, Quercus spp., Liquidambar styraciflua, Magnolia schiedeana, and Podocarpus spp. Beech total population size ranged from 180 to 6300 trees with a total of less than 1300 individuals in four sites. Anthropogenic disturbance remains a major threat to these forests. It is uncertain whether Mexican beech will be able to survive without conservation efforts.
Resource Type: Journal PapersOur results show that any further infrastructure development will put the remaining European population of wild mountain reindeer at great risk, as further habitat fragmentation will make the remaining undisturbed patches too small for holding viable populations. We discuss the importance of controlling piecemeal development in infrastructure for conservation of wildlife and argue that minimizing infrastructure development is likely one of the largest challenges in wildlife conservation ahead.
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