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 PapersProjections indicate that species and ecosystems will be at maximum risk from human activities during the next few decades. Prompt action by the world community can minimise the eventual loss of species. Highest priorities should be to: (i) strengthen the management of ecosystems containing a large proportion of global biodiversity; (ii) help developing countries complete their biodiversity strategies and action plans, monitor their own biodiversity, and establish and maintain adequate national systems of conservation areas; (iii) support actions at the global level, providing benefit to all countries in managing their own biodiversity. Generally, resources will best be spent in safeguarding ecosystems and habitats that are viable and important for global biodiversity, and which are threatened by factors that can be controlled cost-effectively. Other important criteria are representativeness, complementarity and insurance.
Resource Type: Journal PapersAquilaria 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 PapersSeveral 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 PapersThis publication presents five of the lectures from the 2004-5 'Environment on the Edge' lecture series. It includes the following themes:
•The Day After Tomorrow - Sir Crispin Tickell
•Oceans on the Edge - Dr. Jane Lubchenco
•Antartica on the Edge? - Professor Chris Rapley
•Biodiversity on the Edge - Dr. Cristián Samper
•Transport on the Edge - Dr. Bernard Bulkin
This publication presents five of the lectures from the 2007 - 2008 'Environment on the Edge' lecture series. It includes the following themes:
•Northern Ireland - An Environment on the Edge - Professor Sharon Turner
•Travelling First Class on the Titanic - Baroness Young
•The economics of climate change: governments, companies and households - Lord Adair Turner
•Creating a healthy environment in China - Professor Sian Griffiths
•Ocean acidification: the other CO2 problem - Professor Nick Owens
•International environmental governance - Professor Robert T. Watson
This publication presents five of the lectures from the 2005-6 'Environment on the Edge' lecture series. It includes the following themes:
•Nature's capital: the key to poverty eradication - Dr. Klaus Töpfer
•Human development in China - Dr Zhao Baige
•Agriculture and food production: Quo vadis - Dr Hans Rudolf Herren
•The changing face of cities - Professor Anne Power
•Women and conservation - Kathryn Fuller
This publication presents five of the lectures from the 2006 - 2007 'Environment on the Edge' lecture series. It includes the following themes:
•Europe on the edge Professor - Jacqueline McGlade
•Are we running out of oil? - Dr Jeremy Leggett and Dr Ian Vann
•The impacts of the Three Gorges Dam - Professor Zhang Jing
•Humans and carbon: a Faustian bargain? - Professor Berrien Moore III
•Valuing sustainability - Richard Saxon CBE
•Transport: a case of systematic sclerosis? - Professor David Fisk
Swietenia macrophylla King (Meliaceae: Swietenioideae) provides one of the premier timbers of the world. The mahogany shoot borer Hypsipyla robusta Moore (Lepidoptera: Pyralidae) is an economically important pest of S. macrophylla throughout Asia, Africa and the Pacific. No viable method of controlling this pest is known. Previous observations have suggested that the presence of overhead shade may reduce attack by H. robusta, but this has not been investigated experimentally. This research was therefore designed to assess the influence of light availability on shoot-borer attack on S. macrophylla, by establishing seedlings under three different artificial shade regimes, then using these seedlings to test oviposition preference of adult moths, neonate larval survival and growth and development of shoot borer larvae.
The results indicate that shading of mahogany seedlings may reduce the incidence of shoot borer attack, by influencing both oviposition and larval development. The establishment of mahogany under suitable shade regimes may therefore provide a basis for controlling shoot borer attack using silvicultural approaches.
Resource Type: Journal PapersSince 1997, UNEP has produced Global Environment Outlook (GEO) reports providing assessments of the interactions between environment and society. With its core mandate of “keeping the global environment under review,” UNEP coordinated a series of scientific assessments that included extensive consultations and participatory processes, resulting in the production of GEO reports in 1997, 1999 and 2002.
GEO-4 provides an overview of global social and economic trends, and the state-and-trends of the global and regional environments over the past two decades, as well as the human dimensions of these changes. It highlights the interlinkages as well as the challenges of environmental change and opportunities that the environment provides for human wellbeing. It provides an outlook for the future, and policy options to address present and emerging environmental issues.
It places sustainable development at the core of the assessment, particularly on issues dealing with intra- and intergenerational equity. The analyses include the need and usefulness of valuation of environmental goods and services, and the role of such services in enhancing development and human well-being, and minimizing human vulnerability to environmental change
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