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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

The practical application of arbuscular mycorrhizal fungi for reforestation in Indonesia

Setiadi, Yadi January 1995 (has links)
No description available.
302

Development of a spatially explicit forest succession model

Williams, Mathew January 1994 (has links)
No description available.
303

The restoration of tropical dry forest after agriculture in Chiapas, Mexico

Hammond, David Scott January 1991 (has links)
No description available.
304

Structure and dynamics of a gallery forest in central Brazil

Felfili, Jeanine Maria January 1993 (has links)
No description available.
305

Regeneration and succession following shifting cultivation and dry tropical deciduous forests of Sri Lanka

Perera, G. A. Dhammika January 1998 (has links)
No description available.
306

The social construction of an environmental problem : 'Waldsterben' in Germany

Hunter, Jennifer January 1999 (has links)
No description available.
307

Environmental effects on the productivity of Eucalyptus camaldulensis, Leucaena leucocephala and Gliricidia sepium in Central America

Campos Arce, Jose J. January 1989 (has links)
No description available.
308

Modelling Effects of Partial Harvesting on Wildlife Species and their Habitat

Vanderwel, Mark Christopher 03 March 2010 (has links)
In Canada’s eastern boreal forest region, partial-harvest silviculture has garnered increasing support for maintaining wildlife species and habitat structure associated with late-successional forests. If late-successional species can find suitable habitat in managed stands that retain a certain number, type, and pattern of live trees, then partial harvesting might represent a viable tool for maintaining species associated with old and complex forests. I used several indirect forms of inference to evaluate whether late-successional vertebrate species can be maintained within partially harvested stands in the eastern boreal forest. A meta-analysis of studies across North America showed that no bird species decreased in abundance by half where light harvesting retained at least 70% of live trees. However, adverse effects occurred at lower levels of retention, with some bird species unlikely to use harvested stands with less than 50% retention until appropriate habitat structure returned. A spatially explicit stand dynamics model showed that while partial harvesting can promote development of understory saplings, downed wood, and heterogeneity, it can also induce long-term decreases in the abundances of large trees and snags. Consequently, species dependent on the latter, such as brown creepers (Certhia americana) and northern flying squirrels (Glaucomys sabrinus), were projected to be more susceptible to partial harvesting than those associated with other types of structure. At a more detailed scale, a neighbourhood model developed from live-trapping data revealed that southern red-backed voles (Myodes gapperi) exhibited local associations with several late-successional features within boreal mixedwood stands. Their associations with some features depended on stand-level habitat conditions, which suggested that vole habitat in managed stands could be improved by retaining live trees and downed wood. A spatially explicit model of optimal home range establishment that incorporated these relationships fit vole abundance data marginally better than an aspatial habitat model. When the home range model was applied to simulated partially harvested stands, it predicted that spatial heterogeneity could have a positive effect on vole abundance, but only at harvest intensities of 70-90% with suppressed shrub cover. With careful attention to issues such as these, partial-harvest silviculture could be useful in maintaining vertebrate biodiversity within eastern boreal forests.
309

Ecology, management and conservation of Pinus roxburghii forests of the Kumaun Himalaya, India

Burfal, B. S. January 1988 (has links)
No description available.
310

Utility-based social shadow pricing and its comparison with other evaluation techniques : A cost-benefit study of fuelwood plantations in Bihar, India

Trivedi, S. N. January 1987 (has links)
No description available.

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