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IssuespâturageLandLibrary Resource
Displaying 277 - 288 of 626

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

Journal Articles & Books
Décembre, 2014
Argentine

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
Décembre, 2014
États-Unis d'Amérique

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.

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

Journal Articles & Books
Décembre, 2014
Norvège

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.

Effects of crop abandonment and grazing exclusion on available soil water and other soil properties in a semi-arid Mongolian grassland

Journal Articles & Books
Décembre, 2009

Improper cropping and overgrazing have led to land degradation in semi-arid regions, resulting in desertification. During desertification, vegetation changes have been widely observed, and are likely controlled to some extent by soil water. The purpose of this study was to investigate changes in soil physical properties, organic C, and vegetation induced by land-use changes, with special reference to the dynamics of available soil water.

Land use and disturbance effects on the dynamics of natural ecosystems of the Monte Desert: Implications for their management

Journal Articles & Books
Décembre, 2009

The complex interactions between human activity and natural processes determine non-linear dynamics in ecosystems that can difficult their management. Human settlements in arid lands contribute to the modification of disturbance regimes, including the introduction of new disturbances and the elimination of others. In consequence, they can alter the functional mechanisms that allow systems to overcome limiting factors, leading to desertification.

Contribution of cork oak plantations installed after 1990 in Portugal to the Kyoto commitments and to the landowners economy

Journal Articles & Books
Décembre, 2012
Portugal

Cork oak stands are a part of the agroforestry ecosystem in Portugal, characterized by a low crown cover from cork oak trees, managed towards cork production, and sometimes in combination with grazing. In recent years, European Union policies gave impetus to a large area of new cork oak plantations, which have been established mainly for cork production purposes, and consequently with higher stand density than traditional agroforestry systems.

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
Décembre, 2014
Chine

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.

Variation in the local population dynamics of the short‐lived Opuntia macrorhiza (Cactaceae)

Journal Articles & Books
Décembre, 2015

Spatiotemporal variation in demographic rates can have profound effects for population persistence, especially for dispersal‐limited species living in fragmented landscapes. Long‐term studies of plants in such habitats help with understanding the impacts of fragmentation on population persistence but such studies are rare. In this work, we reanalyzed demographic data from seven years of the short‐lived cactus Opuntia macrorhiza var. macrorhiza at five plots in Boulder, Colorado.

Winter Bird Habitat Use in a Heterogeneous Tallgrass Prairie

Journal Articles & Books
Décembre, 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.

Climate change and grazing interact to alter flowering patterns in the Mongolian steppe

Journal Articles & Books
Décembre, 2014
Mongolie

Socio-economic changes threaten nomadic pastoralism across the world, changing traditional grazing patterns. Such land-use changes will co-occur with climate change, and while both are potentially important determinants of future ecosystem functioning, interactions between them remain poorly understood. We investigated the effects of grazing by large herbivores and climate manipulation using open-top chambers (OTCs) on flower number and flowering species richness in mountain steppe of northern Mongolia.

Early human impact (5000–3000 BC) affects mountain forest dynamics in the Alps

Journal Articles & Books
Décembre, 2015

The resilience, diversity and stability of mountain ecosystems are threatened by climatic as well as land‐use changes, but the combined effects of these drivers are only poorly understood. We combine two high‐resolution sediment records from Iffigsee (2065 m a.s.l.) and Lauenensee (1382 m a.s.l.) at different elevations in the Northern Swiss Alps to provide a detailed history of vegetational changes during the period of first pastoralism (ca. 7000–5000 cal. BP, 5000–3000 BC) in order to understand ongoing and future changes in mountain ecosystems.

Resolving Range Conflict in Nevada? Buyouts and Other Compensation Alternatives

Journal Articles & Books
Décembre, 2006

To mitigate the adverse effects of reduced access to public forage, ranchers may require financial or other forms of "compensation." In this paper, we use results from a survey of Nevada ranchers to examine their willingness to sell grazing permits and participate in other schemes that enable them to continue ranching in spite of declining access to public forage.