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Integrative fuzzy set pair model for land ecological security assessment: a case study of Xiaolangdi Reservoir Region, China

Journal Articles & Books
Décembre, 2010
Chine

Due to the increasingly serious ecological degradation of land systems, the land ecological security issues have attracted more and more attention of policy makers, researchers and citizens. Aiming at overcoming the disadvantages in subjectivity and complexity of the currently used assessment methods, an integrative fuzzy set pair model for assessing the land ecological security was developed by integrating fuzzy assessment and set pair analysis (SPA).

conceptual framework to analyse the land-use/land-cover changes and its impact on phytodiversity: a case study of North Andaman Islands, India

Journal Articles & Books
Décembre, 2010
Inde

Phytodiversity is affected both by natural and anthropogenic factors and in Island ecosystems these impacts can devastate or reduce diversity, if the native vegetation is lost. In addition to rich species richness and diversity, Island systems are the sites of high endemism and any threat to these ecosystems will consequently lead to loss and extinction of species.

comparison of alternative modelling approaches to evaluate the European forest carbon fluxes

Journal Articles & Books
Décembre, 2010
Europe

The European forest carbon balance studied by various methods shows different results. We compared the regional and national net primary production (NPP) estimated by the forest inventory-based model EFISCEN and the climate-based terrestrial ecosystem models (TEMs: BIOME-BGC, ORCHIDEE, and JULES), and single forests NPP derived from the international network of eddy-covariance towers (FLUXNET). In addition, the paper presents the net ecosystem production (NEP) and the net biome production (NBP) calculated with EFISCEN and discusses the influence of forest management onto carbon fluxes.

comparative assessment of land cover dynamics of three protected forest areas in tropical eastern Africa

Journal Articles & Books
Décembre, 2010
Ouganda
Kenya
Afrique
Afrique orientale

Processes of deforestation, known to threaten tropical forest biodiversity, have not yet been studied sufficiently in East Africa. To shed light on the patterns and causes of human influences on protected forest ecosystems, comparisons of different study areas regarding land cover dynamics and potential drivers are needed. We analyze the development of land cover since the early 1970s for three protected East African rainforests and their surrounding farmlands and assess the relationship between the observed changes in the context of the protection status of the forests.

Biotic and Abiotic Changes in Ecosystem Structure over a Shrub-Encroachment Gradient in the Southwestern USA

Journal Articles & Books
Décembre, 2010
États-Unis d'Amérique

In this study, we investigate changes in ecosystem structure that occur over a gradient of land-degradation in the southwestern USA, where shrubs are encroaching into native grassland. We evaluate a conceptual model which posits that the development of biotic and abiotic structural connectivity is due to ecogeomorphic feedbacks. Three hypotheses are evaluated: 1. Over the shrub-encroachment gradient, the difference in soil properties under each surface-cover type will change non-linearly, becoming increasingly different; 2.

Predicting China’s Land-use Change and Soil Carbon Sequestration under Alternative Climate Change Scenarios

Conference Papers & Reports
Décembre, 2010
Chine

This paper examines and predicts the effects of climate change and climate extremeson China’s land use conversion and soil carbon sequestration under two alternativeclimate change scenarios. It intends to investigate the following three questions. 1)How did climate factors affect land-use conversion in China from 1988 to 2000 andwhat was the relative importance of these factors? 2) How would the predicted futureclimate change pattern affect land-use choice under alternative climate changescenarios?

Strong light inhibits germination of Artemisia sphaerocephala and A. ordosica at low temperature and its relevance to revegetation in sandy lands of Inner Mongolia, China

Journal Articles & Books
Décembre, 2010
Chine

Artemisia sphaerocephala and A. ordosica are two dominant shrub species in Mu Us sandy land (Inner Mongolia, China) and are widely used for vegetation restoration. However, there are two different conclusions about the effect of light on their germination: light promotes germination versus light inhibits germination. The aim of this study was to evaluate these two conclusions and relate the results to instances of failure of these two species to germinate well when air-dispersed in revegetation projects.

Response of green alder (Alnus viridis subsp. fruticosa) patch dynamics and plant community composition to fire and regional temperature in north-western Canada

Journal Articles & Books
Décembre, 2010
Canada

Feedbacks between climate warming and fire have the potential to alter Arctic and sub-Arctic vegetation. In this paper we assess the effects and interactions of temperature and wildfire on plant communities across the transition between the Arctic and sub-Arctic. Mackenzie Delta region, Northwest Territories, Canada. We sampled air temperatures, green alder (Alnus viridis ssp. fruticosa) cover, growth, reproduction and age distributions, and overall plant community composition on burned and unburned sites across a latitudinal gradient.

Soil organic carbon stocks on long-term agroecosystem experiments in Canada

Journal Articles & Books
Décembre, 2010
Canada

Several long-term agroecosystem experiments (LTAEs) across Canada have been maintained for periods of up to a century. Much scientific knowledge of changes in soil properties through time has been learned from these few, highly productive LTAEs. We determined the effects of land management changes (LMC) on soil organic carbon (SOC) by re-sampling 27 LTAEs across Canada using identical sampling and laboratory protocols.

Physical properties of dystrophic Red Latosol (Oxisol) under different agricultural uses

Journal Articles & Books
Décembre, 2010

Obtaining information about soil properties under different agricultural uses to plan soil management is very important with a view to sustainability in the different agricultural systems. The aim of this study was to evaluate changes in certain indicators of the physical quality of a dystrophic Red Latosol (Oxisol) under different agricultural uses. The study was conducted in an agricultural area located in northern Paraná State.

Land Transitions in the Tropics: Going Beyond the Case Studies

Journal Articles & Books
Décembre, 2010

Estimates of the percent of Earth's land surface that has either been transformed or degraded by human activity range between 39 and 50 percent, with agriculture accounting for the vast majority of these changes. Although much of the focus of research on land use and cover change in the tropics has been on deforestation, ongoing socioeconomic changes both locally and globally have made land transitions in the tropics extremely fluid. In addition, feedbacks between land cover change and human behavior constrain the extent and trajectories of land transitions.