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Land-cover data improve bioclimatic models for anurans and turtles at a regional scale

Journal Articles & Books
Décembre, 2009
Canada

We investigated whether accounting for land cover could improve bioclimatic models for eight species of anurans and three species of turtles at a regional scale. We then tested whether accounting for spatial autocorrelation could significantly improve bioclimatic models after statistically controlling for the effects of land cover. Nova Scotia, eastern Canada. Species distribution data were taken from a recent (1999-2003) herpetofaunal atlas. Generalized linear models were used to relate the presence or absence of each species to climate and land-cover variables at a 10-km resolution.

Relative impacts of disturbance and temperature: persistent changes in microenvironment and vegetation in retrogressive thaw slumps

Journal Articles & Books
Décembre, 2009

In the Low Arctic, a warming climate is increasing rates of permafrost degradation and altering vegetation. Disturbance associated with warming permafrost can change microclimate and expose areas of ion-rich mineral substrate for colonization by plants. Consequently, the response of vegetation to warming air temperatures may differ significantly from disturbed to undisturbed tundra.

Participatory planning, management and alternative livelihoods for poor wetland-dependent communities in Kampala, Uganda

Journal Articles & Books
Décembre, 2009
Ouganda

The paper is based on an on-going 3-year study in the wetland communities of Kampala. The study uses participatory methods and aims to contribute to (i) the development of low-income wetland communities, (ii) to prepare these communities to become less dependent on wetlands without receding into poverty, and (iii) the better management of the wetlands. The communities in direct dependence and intimate interaction with Nakivubo wetlands are mainly poor, live and work under hazardous conditions, and their activities pose a threat to the ecological function of the wetlands.

What are the social impacts of land use restrictions on local communities? Empirical evidence from Costa Rica

Conference Papers & Reports
Décembre, 2009
Costa Rica
Global

Global efforts to reduce deforestation rely heavily on protected areas and land use restrictions. The effect of these restrictions on local communities is currently the subject of heated debate among conservation and development experts. Measuring the social impacts of protected areas is difficult because the effects cannot be isolated from other factors, given the nonrandom placement of protection.

Effects of grazing and experimental warming on DOC concentrations in the soil solution on the Qinghai-Tibet plateau

Journal Articles & Books
Décembre, 2009

Little information is available about the effects of global warming and land management on dissolved organic carbon (DOC) concentration in soil solution in the field. Here, for the first time, we used a free-air temperature enhancement (FATE) system in a controlled warming-grazing experiment in 2006 and 2007 to test the hypothesis that grazing modifies the response of soil solution DOC concentration to experimental warming.

Determining the effects of habitat management and climate on the population trends of a declining steppe bird

Journal Articles & Books
Décembre, 2009
Europe

The Little Bustard Tetrax tetrax is one of the most threatened steppe bird species in Europe, due mainly to agricultural intensification. Despite the relative importance of the Iberian population (approximately 50% of the global population) little is known about its dynamics and trends, especially in core distribution areas. This study evaluates the influences of meteorological factors and land management on the oscillations and medium-term trends of two Little Bustard populations in Central Spain.

Assessing the effectiveness of protected areas: paradoxes call for pluralism in evaluating conservation performance

Journal Articles & Books
Décembre, 2009
Tanzania

To highlight and examine apparent paradoxes in assessing the effectiveness of different forms of land-use for biodiversity conservation. Tanzania. We compare and contrast the findings of two recent and seemingly conflicting studies on the effectiveness of conservation protection strategies in Tanzania. We evaluate these studies in the context of a wider body of evidence relating to the problem of determining protected area performance.

potential ecological costs and cobenefits of REDD: a critical review and case study from the Amazon region

Journal Articles & Books
Décembre, 2009

The United Nations climate treaty may soon include a mechanism for compensating tropical nations that succeed in reducing carbon emissions from deforestation and forest degradation, source of nearly one fifth of global carbon emissions. We review the potential for this mechanism [reducing emissions from deforestation and degradation (REDD)] to provoke ecological damages and promote ecological cobenefits.

Tracking the rhythm of the seasons in the face of global change: phenological research in the 21st century

Journal Articles & Books
Décembre, 2009

Phenology is the study of recurring life‐cycle events, classic examples being the flowering of plants and animal migration. Phenological responses are increasingly relevant for addressing applied environmental issues. Yet, challenges remain with respect to spanning scales of observation, integrating observations across taxa, and modeling phenological sequences to enable ecological forecasts in light of future climate change.

Modeling soil organic carbon stocks and changes in a Nepalese watershed

Journal Articles & Books
Décembre, 2009
Népal

Land use, land use change and forestry activities play an important role in determining whether soil is a sink or source of atmospheric carbon dioxide (CO₂). The effects of land use change on greenhouse gases and climate change are receiving greater attention in many developing countries. We simulated changes in soil organic carbon (SOC) pool over 100 years (1950-2050) under managed dense Shorea forest (DS), rainfed upland (Bari) and irrigated low land (Khet) of Pokhare Khola, a mid-hill watershed of Nepal, using the Century model.

Uso de las tierras, fisiografía y degradación, en el noreste del departamento Aluminé, Neuquén

Journal Articles & Books
Décembre, 2009

Kilca River basin is one of the major river systems before the mountain region, located in the center of the province of Neuquen. In this zone, humid climates, the dominant land use is "veranada", which consists of three annual steps of one type of livestock transhumance, based on the exploitation of natural grassland forage. Given the physiographic formation of these landscapes, there is in them a high propensity to develop geomorphological processes of erosion and landslides.