Tropical 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 Papers
The 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 Papers
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 Papers
The success of protected areas as a tool for conservation is based around the assumption that they are managed to protect the values that they contain. To be effective, management should be tailored to the particular demands of the site, given that each protected area has a variety of biological and social characteristics, pressures and uses. Achieving effective management is not an easy task – it requires adopting appropriate management objectives and governance systems, adequate and appropriate resourcing and the timely implementation of appropriate management strategie and processes. It is unlikely to be achieved fully without an approach to management that is inquiring an reflective – that seeks to understand how effective the current management regime is and how it could be improved. Information on management effectiveness is thus a cornerstone of good management.
Araucaria araucana (Monkey Puzzle), a southern South American tree species of exceptional cultural and economic importance, is of conservation concern owing to extensive historical clearance and current human pressures. Random amplified polymorphic DNA (RAPD) markers were used to characterise genetic heterogeneity within and among 13 populations of this species from throughout its natural range.
Although populations are geographically divided into Chilean Coastal, Chilean Andes and Argentinean regions, this grouping explained only 1.77 of the total variation. Within Andean groups there was evidence of a trend of genetic distance with increasing latitude, and clustering of populations across the Andes, suggesting postglacial migration routes from multiple refugia. Implications of these results for the conservation and use of the genetic resource of this species are discussed.Resource Type: Journal Papers
Aquilaria spp. (Thymelaeaceae) are the principal source of Gaharu, a valuable resin, yet information about their reproductive ecology is almost entirely lacking. Individuals of six species (A. beccariana, A. crasna, A. filaria, A. hirta, A. malaccensis and A. microcarpa) in cultivation in Indonesia were investigated to assess reproductive phenology, pollination, seed production and germination. Seed production and seedling dispersion were also assessed in natural populations of A. beccariana, A. malaccensis and A. microcarpa in Kalimantan.
The results indicate that Aquilaria spp. have high reproductive potential, but suggest that seed dispersal might be limited in natural forests. The implications of these results for the management of Aquilaria spp. are discussed.Resource Type: Journal Papers
Sustainability requires living within the regenerative capacity of the biosphere. In an attempt to measure the extent to which humanity satisfies this requirement, we use existing data to translate human demand on the environment into the area required for the production of food and other goods, together with the absorption of wastes. Our accounts indicate that human demand may well have exceeded the biosphere's regenerative capacity since the 1980s. According to this preliminary and exploratory assessment, humanity's load corresponded to 70% of the capacity of the global biosphere in 1961, and grew to 120% in 1999.Resource Type: Journal Papers
Aquilaria malaccensis (Thymelaeaceae) is the principal source of gaharu, one of the most valuable tropical forest products in international trade. Despite its economic importance, the autecology of this species is virtually unknown. Seedling growth and survival of A. malaccensis was monitored over a 15-month period in natural forest in West Kalimantan. Mean height growth rate was 21.2 + 2.3 cm year1, and was positively related to light availability (i^= 0.79, p < 0.001), but unrelated to distance to the nearest mature tree or seedling density. By the end of the observation period, fewer than 20% of seedlings surveyed initially were still alive, trampling and cutting being one of the main causes of mortality. A nursery experiment examined the influence of soil (two treatments), light availability (four treatments) and seedling density (four treatments) on growth. Although a decrease in irradiance was associated with significantly (p < 0.01, t - test) lower values for height and stem diameter, seedlings were able to survive under the low light treatment. Lower height growth rates and leaf increment were observed with higher seedling densities on the more fertile soil; no such effects of density were observed on the relatively infertile soil. The implications of these results for the sustainable management of A. malaccensis are discussed.Resource Type: Journal Papers
Aquilaria spp. are the main source of gaharu, one of the most valuable non-timber products harvested from tropical forests. In order to assess the impact of gaharu harvesting on populations of Aquilaria spp. in Indonesia, the activities of gaharu collectors were assessed by accompanying them on collecting expeditions.
Given current harvesting practices, it is unlikely that gaharu is being sustainably harvested at present. The results suggest that the gaharu trade may have had a substantial impact on the population size of Aquilaria spp. in Indonesia, and their implications are discussed in the context of setting harvest quotas for regulation of trade, as required by CITES.Resource Type: Journal Papers
Several populations of Fitzroya cupressoides (Mol.) Johnst. (Cupressaceae, common name 'alerce'), a threatened, long-lived conifer endemic to southern Chile and parts of Argentina, have recently been found in Chile's Central Depression, where the species was thought to have been extirpated. The objective of this study was to determine, on eight sites in the Depression, Fitzroya's regeneration behavior in relation to disturbance, its substrate and cover requirements for establishment, and whether regeneration is by seed or vegetative means.
Despite substantial environmental differences between the Central Depression and the portions of the Coastal and Andean Cordilleras where Fitzroya is found, populations in all three regions show striking similarities in their regeneration and stand dynamics. Fitzroya's longevity and at times abundant regeneration provide the biological basis for its persistence in Chile's Central Depression.Resource Type: Journal Papers
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