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impact of land-use change on larval insect communities: Testing the role of habitat elements in conservation

Journal Articles & Books
декабря, 2008
Costa Rica

Conservationists have proposed that maintaining key elements of the original land-cover type in modified landscapes may mitigate the detrimental effects of land-cover change on residual species. We tested this hypothesis for aquatic insect communities in tank-forming bromeliads in forested and non-forested habitats in Costa Rica. Bromeliad tanks hold much of the standing water in this region and therefore provide an important resource for insects with aquatic larval stages.

Evolving more sustainable agriculture in the Cameron Highlands, Malaysia

Journal Articles & Books
декабря, 2008
Malaysia

Smallholders in many tropical highlands cause serious environmental damage. The Cameron Highlands of Malaysia offer an excellent opportunity for studying how farmers interact with environment, changing markets, infrastructure development, indigenous peoples, and tourism, and how these shape innovation. Our surveys in 2002-2004, 2006 and 2007 show that farmers have intensified production and in doing so some have adopted less damaging practices. We assess trends and causation of changes; this offers opportunities for more proactive management.

Climate change and impact of desertification or soil/ land degradation in Turkey, combating desertification

Journal Articles & Books
декабря, 2008
Turkey

The total arable land of Turkey is about 28,054,000 ha. The main income of the country is agriculture and agriculture based industry. However, the prime soils cover only 17.5% of the total land surface and the productivity of the rest of the soils is limited by topographical, chemical (e.g. high calcium carbonate content, alkalinity and low organic matter), and physical (e.g. water logging, texture) attributes. The diverse topography along with deforestation and unsuitable tillage and irrigation management has been inducing the rate of erosion in the country for centuries.

Threshold changes in vegetation along a grazing gradient in Mongolian rangelands

Journal Articles & Books
декабря, 2008
Mongolia

1. The concept of threshold has become important in ecology, but the nature of potential threshold responses of vegetation to grazing in rangeland ecosystems remains poorly understood. We aimed to identify ecological thresholds in vegetation changes along a grazing gradient and to examine whether threshold changes were expressed similarly at a variety of ecological sites. 2. To accomplish this, we surveyed the vegetation along grazing gradients at 10 ecological sites, each located at different landscape positions in Mongolia's central and southern rangelands.

Soil chemical and microbiological properties along a chronosequence of Caragana microphylla Lam. plantations in the Horqin sandy land of Northeast China

Journal Articles & Books
декабря, 2008

Caragana microphylla Lam., a leguminous shrub, is a dominant native plant species widely planted to stabilize the moving and semi-moving sand dunes in the semi-arid Horqin sandy land of Northeast China. The objective of this study was to determine how C. microphylla plantations affected the physical, chemical and microbiological properties of a sandy soil. Soil samples at the depths of 0-10, 10-20, 20-30, 30-40, and 40-50cm were collected from the C. microphylla plantations with an age sequence of 0, 5, 10, and 23 years.

roles of roads and agricultural land use in altering hydrological processes in Nam Mae Rim watershed, northern Thailand

Journal Articles & Books
декабря, 2008
Thailand

The distributed hydrology soil vegetation model (DHSVM) is applied in the 107 km² Nam Mae Rim watershed (NMRW) in northern Thailand. Simulations using land cover scenarios for 1989 and 2002, extreme deforestation, and forest, each run with and without roads, show that roads have very small effects on the mean water fluxes, but significantly increase peak flows for all land cover scenarios. The magnitude of the road effect on peak flow depends on the land cover context in which the roads are placed.