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Temporal nutrient variation in soil and vegetation of post-forest pastures as a function of soil order, pasture age, and management, Rondonia, Brazil

Journal Articles & Books
Dezembro, 2007
Brasil

Understanding pasture degradation processes is key for sustainable development in the Amazon region. Pasture degradation can be indexed by pasture nutritional status, which is impacted by environmental and human related factors. Most studies of the biogeochemistry of Amazonian pastures have been restricted to highly acidic soils with little focus on how management affects pasture biogeochemistry. We investigated soil physical and chemical properties and grass nutrients under different edaphic conditions and management practices in Rondônia state, in the southwestern Amazon region.

Predicting the Impacts of Future Sea-Level Rise on an Endangered Lagomorph

Journal Articles & Books
Dezembro, 2007

Human-induced global climate change presents a unique and difficult challenge to the conservation of biodiversity. Despite increasing attention on global climate change, few studies have assessed the projected impacts of sea-level rise to threatened and endangered species. Therefore, we estimated the impacts of rising sea levels on the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) across its geographic distribution under scenarios of current conditions, low (0.3-m), medium (0.6-m), and high (0.9-m) sea-level rise.

Adaptive Ecosocial System Sustainability Enhancement in Sub-Saharan Africa

Journal Articles & Books
Dezembro, 2007
Etiópia
África

A conceptual framework is developed and used for improving the livelihood of Sub-Saharan communities faced with multiple stresses resulting from adverse environments, vector-transmitted diseases, and limited food. Ecosocial systems are the units for management. The accumulation of ecological, economic, and social capital is the objective of management, the reduction of maintenance costs is the key strategy, and technologies must satisfy ecological, economic, and social criteria.

Farmer management of production risk on degraded lands: the role of wheat variety diversity in the Tigray region, Ethiopia

Journal Articles & Books
Dezembro, 2007
Etiópia

This article investigates the effects of wheat genetic diversity and land degradation on risk and agricultural productivity in less favored production environments of a developing agricultural economy. Drawing production data from a household survey conducted in the highlands of Ethiopia, we estimate a stochastic production function to evaluate the effects of variety richness, land degradation, and their interaction on the mean and the variance of wheat yield. Ethiopia is a center of diversity for durum wheat and farmers manage complex variety mixtures on multiple plots.

Interactions entre systèmes fourragers et systèmes de grandes cultures à l'échelle d'un territoire. Intérêts pour l'environnement

Journal Articles & Books
Dezembro, 2007

In certain regions where mixed farming prevails, the specialization of the farms (with the progressive disappearance of livestock) has brought about uniform methods of land occupation which run counter the environmental functions of farming. For that matter, grasslands and perennial covers have beneficial effects, but their insertion or their maintenance have to be thought out at the territorial scale.

Aeolian desertification from the mid-1970s to 2005 in Otindag Sandy Land, Northern China

Journal Articles & Books
Dezembro, 2007

Aeolian desertification in Otindag Sandy Land has expanded dramatically during the past 50 years. This research explored processes and causes of aeolian desertification in the study area. The results showed that aeolian desertification development in Zhenglan Qi of typical region located at the center in the study area can be divided into three stages including rapid occurrence before 1987, parts of rehabilitation and most of deterioration from 1987 to 2000 and little rapid rehabilitation occurrence from 2000 to 2005, according to remote sensing images and field investigations.

Modeling and assessing land-use and hydrological processes to future land-use and climate change scenarios in watershed land-use planning

Journal Articles & Books
Dezembro, 2007
Taiwan

Effective information regarding environmental responses to future land-use and climate change scenarios provides useful support for decision making in land use planning, management and policies. This study developed an approach for modeling and examining the impacts of future land-use and climate change scenarios on streamflow, surface runoff and groundwater discharge using an empirical land-use change model, a watershed hydrological model based on various land use policies and climate change scenarios in an urbanizing watershed in Taiwan.