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Plant phenotypic functional composition effects on soil processes in a semiarid grassland

Journal Articles & Books
Dezembro, 2013

Our knowledge of plant functional group effects on ecosystem processes is relatively well established, but we know much less on how changes in plant phenotypic composition affect ecosystem functioning (i.e., phenotypic functional composition). Understanding phenotypic functional composition (PFC) is relevant in plant communities strongly dominated by a few keystone species, since alteration of phenotypic composition of these species might be a mechanisms by which land management practices such as grazing impact on ecosystem functioning.

Impacts of heavy grazing on plant species richness: A comparison across rangeland biomes of South Africa

Journal Articles & Books
Dezembro, 2013
África do Sul
África austral

The net effect of heavy grazing and land degradation on plant diversity and richness is insufficiently understood for incorporation in national biodiversity assessments. A study was undertaken to determine the effects of heavy grazing primarily on richness of vascular plant species across the arid and semi-arid rangeland biomes of South Africa. Major grazing contrasts were systematically identified for sampling in rangelands of Succulent Karoo, Nama-Karoo, Thicket, Grassland, Kalahari dune savanna and Mopane savanna.

Ploughing and grazing alter the spatial patterning of surface soils in a shrub-encroached woodland

Journal Articles & Books
Dezembro, 2013

Grazing is known to affect the spatial patterning of soil resources through biologically-mediated processes such as the removal of plant biomass and deposition of dung. In dense shrublands, grazing is thought to reinforce the concentration of resources around shrubs (fertile island effect) by enhancing the movement of resources from the interspace to the shrub hummocks. Shrub removal practices such as ploughing, which is commonly used to manage dense shrub patches, has unknown impacts on the distribution of soil properties.

effects of a deferred grazing system on rangeland vegetation in a north-western, semi-arid region of Tanzania

Journal Articles & Books
Dezembro, 2013
Tanzania

The present study assessed the effects of deferred grazing management on rangeland condition using aboveground biomass, vegetation cover and species composition as indicators of range condition. The experiment was based on traditionally conserved exclosures (ngitili). Data were collected in Shinyanga rural and Meatu districts, Tanzania, from October to November 2011. Five grazing strategies were compared: old private ngitili , young private ngitili , old communal ngitili , young communal ngitili and continuously grazed land.

Conservation Practices for Climate Change Adaptation

Journal Articles & Books
Dezembro, 2013
Estados Unidos

The threat of climate change is a great challenge to sustainable land management (USDA-NRCS, 2010a). Several publications have reported that over the last few decades, rainfall intensities have increased in many parts of the world, including in the United States. Without good, productive soils and the ecosystem services provided by them, the survival of our species will be in jeopardy. The future changes in climate that will drive erosion processes will significantly impact soil erosion rates, with higher projected erosion rates for the United States.

Grazing management or physiography? Factors controlling vegetation recovery in Mediterranean grasslands

Journal Articles & Books
Dezembro, 2013
Espanha

Grazing intensification and abandonment are increasing the risk of degradation of Mediterranean grasslands. The development of techniques for monitoring grazing effects on herbaceous vegetation is an essential need for the management of these rangelands. However, the high variability of these systems make physiographical and management effects hard to disentangle and quantify. We present a methodology to support rangeland management and assess grazing effects on environmentally heterogeneous areas, and provide an example of its application in a Mediterranean rangeland in central Spain.

Model-based analysis of the environmental impacts of grazing management on Eastern Mediterranean ecosystems in Jordan

Journal Articles & Books
Dezembro, 2013
Jordânia

Eastern Mediterranean ecosystems are prone to desertification when under grazing pressure. Therefore, management of grazing intensity plays a crucial role to avoid or to diminish land degradation and to sustain both livelihoods and ecosystem functioning. The dynamic land-use model LandSHIFT was applied to a case study on the country level for Jordan. The impacts of different stocking densities on the environment were assessed through a set of simulation experiments for various combinations of climate input and assumptions about the development of livestock numbers.

Performance of exclosure in restoring soil fertility: A case of Gubalafto district in North Wello Zone, northern highlands of Ethiopia

Journal Articles & Books
Dezembro, 2013
Etiópia

Inappropriate agricultural practices and conversion of marginal land to cultivation and grazing have led to severe land degradation in the Ethiopian highlands. Consequently, the government has invested substantial resources in soil and water conservation (SWC). One of such interventions was exclosure, which was aimed restoring biodiversity, biomass and soil fertility. The aim of this study was to analyze the impact of exclosures on soil fertility restoration and examine its variability across age, agro-ecology and landscape position.

Prevalence and risk factors for infection of bovine tuberculosis in indigenous cattle in the Serengeti ecosystem, Tanzania

Journal Articles & Books
Dezembro, 2013
Tanzania

BACKGROUND: Bovine tuberculosis (bTB) is a chronic debilitating disease and is a cause of morbidity and mortality in livestock, wildlife and humans. This study estimated the prevalence and risk factors associated with bovine tuberculosis transmission in indigenous cattle at the human-animal interface in the Serengeti ecosystem of Tanzania. RESULTS: A total of 1,103 indigenous cattle from 32 herds were investigated for the presence of bTB using the Single Intradermal Comparative Tuberculin Test. Epidemiological data on herd structure, management and grazing system were also collected.

effects of fencing on carbon stocks in the degraded alpine grasslands of the Qinghai-Tibetan Plateau

Journal Articles & Books
Dezembro, 2013

Quantifying the carbon storage of grasslands under different management strategies can help us understand how this ecosystem responds to different land management practices. To assess the C cycle and the importance of soil microbial biomass carbon, we measured the levels of soil organic carbon, biomass carbon (above- and underground) and soil microbial biomass carbon in areas with different grazing intensities and different management strategy (fenced and unfenced) in the Qinghai-Tibetan Plateau.

Collective management on communal grazing lands: Its impact on vegetation attributes and soil erosion in the upper Blue Nile basin, northwestern Ethiopia

Journal Articles & Books
Dezembro, 2013
Etiópia

Collective action, on communal grazing land, has evolved in the highlands of northwestern Ethiopia to mitigate the problems of feed shortage and land degradation due to overgrazing. The exercise is liked by farmers for improving the availability of natural pasture during the long dry season when other feed sources get depleted. However, large portions of the communal grazing lands are still managed under free grazing throughout the year.

Contested institutions? Traditional leaders and land access and control in communal areas of Eastern Cape Province, South Africa

Journal Articles & Books
Dezembro, 2013
África do Sul
África austral

The South African government has endeavoured to strengthen property rights in communal areas and develop civil society institutions for community-led development and natural resource management. However, the effectiveness of this remains unclear as the emergence and operation of civil society institutions in these areas is potentially constrained by the persistence of traditional authorities. Focusing on the former Transkei region of Eastern Cape Province, three case study communities are used examine the extent to which local institutions overlap in issues of land access and control.