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Land‐use drivers of forest fragmentation vary with spatial scale

Journal Articles & Books
декабря, 2014
Australia

AIM: Improving our understanding of the drivers of forest fragmentation is fundamental to mitigating the consequences of anthropogenic fragmentation for biodiversity. Moreover, the impacts of fragmentation on biodiversity depend on the spatial scale at which fragmentation occurs. Therefore, understanding how the effect of land use on fragmentation patterns varies across scales is critical to ensure that fragmentation is managed at scales relevant to the ecology of target species or to land management.

Cattle as ecosystem engineers: New grazing management enhances rangeland biodiversity

Journal Articles & Books
декабря, 2014

A confluence of factors has shaped the composition and structure of vegetation on rangelands in the American West. These factors include climate, soils, topography, history of grazing and fire (both wildfire and prescribed fire) as well as legacy effects from prior land management practices. Despite the inherent differences in vegetation of rangelands resulting from these factors, sustainable management practices involving matching forage availability to forage demand have resulted in managing large acreages in a similar fashion for livestock production.

Effects of supplementing Leucaena leucocephala and conserved forages from natural pasture on the performance of grazing calves

Journal Articles & Books
декабря, 2014

Twelve white Fulani × N'dama cross-bred calves weighing 83.79 ± 1.16� kg were used in an 84-day experiment to investigate the utilization of forage resources from natural grazing land. The experimental diets were sole grazing, grazing + hay, grazing + silage and grazing + Leucaena leucocephala leaves. The calves were divided into four groups of three animals each and were randomly assigned to the four experimental diets. Crude protein (CP) contents of the forages ranged from 59 to 171� g/kg dry matter (DM).

Traditional Livelihoods, Conservation and Meadow Ecology in Jiuzhaigou National Park, Sichuan, China

Journal Articles & Books
декабря, 2014
China

Jiuzhaigou National Park (JNP) is a site of global conservation significance. Conservation policies in JNP include the implementation of two national reforestation programs to increase forest cover and the exclusion of local land-use. We use archaeological excavation, ethnographic interviews, remote sensing and vegetation surveys to examine the implications of these policies for non-forest, montane meadows. We find that Amdo Tibetan people cultivated the valley for >2,000� years, creating and maintaining meadows through land clearing, burning and grazing.

Deforestation of degraded rangelands: The Argentine Chaco enters the next state of the Anthropocene

Journal Articles & Books
декабря, 2014
Argentina

Twenty years ago I completed my Master’s work in the Chaco forests of northern Argentina. The native forests are, in fact, rangelands. In addition to livestock grazing, there is timber extraction, wildlife harvest (think tegu lizard cowboy boots), and charcoal production. I took part in a project comparing biodiversity among production systems. A new system promised to reverse biodiversity loss and soil degradation. But it’s a moot point now since much of that forest has been cleared for cropland—the highest rate of tropical forest loss in the world.

Long-Term Vegetation Change Provides Evidence for Alternate States in Silver Sagebrush

Journal Articles & Books
декабря, 2014
United States of America

A key goal in land management is to prevent ecosystem shifts that affect human well-being. Like other types of sagebrush shrublands, large areas dominated by the common but little-studied mountain silver sagebrush may have shifted to a less productive shrub-dominated alternate state under heavy livestock grazing in the 19th century. The goals of this study are to 1) describe long-term vegetation change in a silver sagebrush mountain park and 2) evaluate evidence that these changes constitute alternate states.

Human Infrastructure and Invasive Plant Occurrence Across Rangelands of Southwestern Wyoming, USA

Journal Articles & Books
декабря, 2014
United States of America

Although human influence across rural landscapes is often discussed, interactions between the native, natural systems and human activities are challenging to measure explicitly. We assessed the distribution of introduced, invasive species as related to anthropogenic infrastructure and environmental conditions across southwestern Wyoming. to discern direct correlations as well as covariate influences between land use, land cover, and abundance of invasive plants, and assess the supposition that these features affect surrounding rangeland conditions.

Evaluation of Landscape-Level Grazing Capacity for Domestic Sheep in Alpine Rangelands

Journal Articles & Books
декабря, 2014
Norway

Balancing the number of grazing animals with the level of plant resources is a core issue in grazing management. Complete, full-coverage vegetation surveys are often used for this purpose, but these are expensive undertakings. We have presented a method to downscale information from regional sampling surveys by poststratification using a land cover map derived from satellite-based measures of reflectance values. This approach opens new prospects for landscape-level evaluation of productivity.

Evaluation of changes in ecological security in China’s Qinghai Lake Basin from 2000 to 2013 and the relationship to land use and climate change

Journal Articles & Books
декабря, 2014
China

Ecological security evaluation is an important way to identify the need for improvement in a watershed and to assess the degree of regional sustainable development. Using a driver–pressure–state–exposure–response model, a comprehensive system of ecological security indicators was developed, and it was demonstrated in a case study of the main ecological problems facing the Qinghai Lake Basin.

Asymmetric Ecological and Economic Responses for Rangeland Restoration: A Case Study of Tree Thickening in Queensland, Australia

Journal Articles & Books
декабря, 2014
Australia

Economic motivation for implementing targeted responses to rangeland degradation often lag the events that cause degradation and existing monitoring schemes often lack the sensitivity or the connections to ecological processes to reliably serve as a basis for evaluating success. In this paper, we present an approach for quantifying the relationship of economic output and land degradation during the intermediate stages of degradation. We also propose an approach that can provide enhanced incentives to implement proven responses before degradation processes are entrained.

Winter Bird Habitat Use in a Heterogeneous Tallgrass Prairie

Journal Articles & Books
декабря, 2014

In the Flint Hills of Kansas and Oklahoma, U.S.A., grazing land is managed predominantly to promote homogeneous grassland structure. This potentially limits the diversity of habitats for grassland obligate songbirds with narrow habitat preferences during the breeding season, prompting ecologists and conservationists to call for managing rangelands for increased heterogeneity. The Flint Hills also hosts multiple species of conservation concern during winter, but avian habitat requirements are less well known during this period and seldom considered in management recommendations.