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Climate impacts on net primary productivity trends in natural and managed ecosystems of the central and eastern United States

Journal Articles & Books
Décembre, 2009
États-Unis d'Amérique

The central and eastern United States is an important food and timber production region and could potentially be a large-scale carbon sink. These characteristics are functions of the human management of the landscape and favorable soil and climate conditions. Large-scale assessments of carbon uptake and trends in net primary productivity (NPP) have been previously reported for this region using satellite observations, but they cannot quantify the contributions from changes in management and technology independently from climate effects.

Agro-ecological field vulnerability evaluation and climate change impacts in Souma area (Iran), using MicroLEIS DSS

Journal Articles & Books
Décembre, 2009
Iran

Soil erosion and contamination are two main desertification indices or land degradation agents in agricultural areas. Global climate change consequence is a priority to predict global environmental change impacts on these degradation risks. This agro-ecological approach can be especially useful when formulating soil specific agricultural practices based on the spatial variability of soils and related resources to reverse environmental degradation.

Realistic Assessment of the Indicator Potential of Butterflies and Other Charismatic Taxonomic Groups

Journal Articles & Books
Décembre, 2009

Charismatic groups of animals and plants often are proposed as sentinels of environmental status and trends. Nevertheless, many claims that a certain taxonomic group can provide more-general information on environmental quality are not evaluated critically. To address several of the many definitions of indicator species, we used butterflies to explore in some detail the attributes that affect implementation of indicators generically.

Introduction to the Special Section on Alternative Futures for Great Basin Ecosystems

Journal Articles & Books
Décembre, 2009
États-Unis d'Amérique

Natural and anthropogenic processes are causing extensive and rapid ecological, social, and economic changes in arid and semiarid ecosystems worldwide. Nowhere are these changes more evident than in the Great Basin of the western United States, a region of 400,000 km² that largely is managed by federal agencies.

modified climate diagram displaying net water requirements of wetlands in arid and semi-arid regions

Journal Articles & Books
Décembre, 2009
Chine

Flooding regimes in arid and semi-arid regions are heavily influenced by climate change and water shortage, water regulations, and increased water demands. Wetlands managed as part of regulated water systems in agricultural landscapes often require external water supplies to sustain or support desired properties or services. Therefore, water resource managers must weigh water requirements necessary to support wetland functions alongside other water demands.

continent under stress: interactions, feedbacks and risks associated with impact of modified land cover on Australia's climate

Journal Articles & Books
Décembre, 2009
Australie
Global

Global climate change is the major and most urgent global environmental issue. Australia is already experiencing climate change as evidenced by higher temperatures and more frequent and severe droughts. These impacts are compounded by increasing land use pressures on natural resources and native ecosystems. This paper provides a synthesis of the interactions, feedbacks and risks of natural climate variability, climate change and land use/land cover change (LUCC) impacting on the Australian continent and how they vary regionally.

Simulated dynamics of carbon stocks driven by changes in land use, management and climate in a tropical moist ecosystem of Ghana

Journal Articles & Books
Décembre, 2009
Ghana
Afrique

Sub-Saharan Africa is large and diverse with regions of food insecurity and high vulnerability to climate change. This project quantifies carbon stocks and fluxes in the humid forest zone of Ghana, as a part of an assessment in West Africa. The General Ensemble biogeochemical Modeling System (GEMS) was used to simulate the responses of natural and managed systems to projected scenarios of changes in climate, land use and cover, and nitrogen fertilization in the Assin district of Ghana.

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.

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.