The high Zoige Basin （Ruoergai Plateau） on the eastern Tibetan Plateau is a fault depression formed during intensive uplifting of the Tibetan Plateau. The wetland is globally important in biodiversity and is compose...The high Zoige Basin （Ruoergai Plateau） on the eastern Tibetan Plateau is a fault depression formed during intensive uplifting of the Tibetan Plateau. The wetland is globally important in biodiversity and is composed of marshes, bogs, fens, wet meadows and shallow water interspersed with low hills and sub-alpine meadows. Most of the Zoige wetlands have long been one of the most important grazing lands in China. Recent rangeland policy has allowed grazing, and usable wetland areas have been being legally allocated to individuals or groups of households on a long-term lease basis. Privatizafion of the wetland has impacted the Zoige wetlands in aspects of hydrologic condition, landscape and biodiversity. The uneven spatial distribution of water resources onprivatelands has led to the practice of extracting ground water, which has decreased the perched water table in Zoige. Fencing off the rangelands and grazing on expanding sand dunes have affected landscapes. Variation in the water table has led to the changes in vegetation diversity, resulting in the changes in wildlife and aquatic diversities and ecosystem processes. Making use all year round of the pasture that was previously grazed only in summer has shrunk the daily activity space of wildlife, and the newly erected fences blocked the movement of wild animals looking for food in the snow to lower and open areas. To maintain the favorable conditions of the Zoige wetland ecosystem, the author suggests that, in addition to biophysical research and implementation of conservation practices, there is an immediate need to initiate an integrated management program, increase public awareness of wetland functions and provide better training for the local conservation staff.展开更多
Controlled grazing is considered a good management strategy to maintain or increase the live weight of livestock and to reduce vegetation degradation of rangelands. The present study investigated soil characteristics,...Controlled grazing is considered a good management strategy to maintain or increase the live weight of livestock and to reduce vegetation degradation of rangelands. The present study investigated soil characteristics, aboveground vegetation biomass dynamics and controlled grazinginduced changes in the live weight of local ewes in the semi-arid rangeland of Ahmadun, Ziarat, Balochistanprovince of Pakistan. An area of 115 ha was protected from livestock grazing in April 2014. In June 2015, soil characteristics within 0-30 cm depth i.e. soil organic matter(SOM), mineral nitrogen, p H and texture in controlled and uncontrolled grazing sites were assessed. Aboveground vegetation biomass measured in early(June) and late summer(August) in 2015 and 2016. The nutritional value i.e. crude protein, phosphorus(P), neutral detergent fiber(NDF), acid detergent fiber(ADF), calcium(Ca), magnesium(Mg) and potassium(K) of dominantplant species were assessed at the beginning of experiment in 2015. Vegetation cover of controlled and uncontrolled grazing sites was also measured during the two years of the study period using the Veg Measure software. From June to November in2015 and 2016, controlled and uncontrolled livestock grazing sites were grazed on a daily basis by local ewes with a stocking rate of 2 and 1 head ha^(-1) respectively. Results reveal that the organic matter contents of coarse-textured, slightly alkaline soil of the study site were in the range of 9.4-17.6 g kg^(-1) soil and showed a strong positive correlation with aboveground vegetation biomass. The biomass of plants was 56.5% and 33% greater at controlled than uncontrolled grazing site in 2015 and 2016 respectively and plant cover was also higher at controlled than uncontrolled grazing site in both years The nutrient contents were significantly(P<0.05)lower in grasses than shrubs. In both years, the controlled grazing increased the weight gain of ewes about two folds compared to the uncontrolled grazing.The results indicate that controlled grazing improved the v展开更多
文摘The high Zoige Basin （Ruoergai Plateau） on the eastern Tibetan Plateau is a fault depression formed during intensive uplifting of the Tibetan Plateau. The wetland is globally important in biodiversity and is composed of marshes, bogs, fens, wet meadows and shallow water interspersed with low hills and sub-alpine meadows. Most of the Zoige wetlands have long been one of the most important grazing lands in China. Recent rangeland policy has allowed grazing, and usable wetland areas have been being legally allocated to individuals or groups of households on a long-term lease basis. Privatizafion of the wetland has impacted the Zoige wetlands in aspects of hydrologic condition, landscape and biodiversity. The uneven spatial distribution of water resources onprivatelands has led to the practice of extracting ground water, which has decreased the perched water table in Zoige. Fencing off the rangelands and grazing on expanding sand dunes have affected landscapes. Variation in the water table has led to the changes in vegetation diversity, resulting in the changes in wildlife and aquatic diversities and ecosystem processes. Making use all year round of the pasture that was previously grazed only in summer has shrunk the daily activity space of wildlife, and the newly erected fences blocked the movement of wild animals looking for food in the snow to lower and open areas. To maintain the favorable conditions of the Zoige wetland ecosystem, the author suggests that, in addition to biophysical research and implementation of conservation practices, there is an immediate need to initiate an integrated management program, increase public awareness of wetland functions and provide better training for the local conservation staff.
基金supported by the USAID under Agriculture Innovation Program (AIP) Pakistansupported by the ICARDA and the CGIAR Research Program on Livestock (CRP Livestock)
文摘Controlled grazing is considered a good management strategy to maintain or increase the live weight of livestock and to reduce vegetation degradation of rangelands. The present study investigated soil characteristics, aboveground vegetation biomass dynamics and controlled grazinginduced changes in the live weight of local ewes in the semi-arid rangeland of Ahmadun, Ziarat, Balochistanprovince of Pakistan. An area of 115 ha was protected from livestock grazing in April 2014. In June 2015, soil characteristics within 0-30 cm depth i.e. soil organic matter(SOM), mineral nitrogen, p H and texture in controlled and uncontrolled grazing sites were assessed. Aboveground vegetation biomass measured in early(June) and late summer(August) in 2015 and 2016. The nutritional value i.e. crude protein, phosphorus(P), neutral detergent fiber(NDF), acid detergent fiber(ADF), calcium(Ca), magnesium(Mg) and potassium(K) of dominantplant species were assessed at the beginning of experiment in 2015. Vegetation cover of controlled and uncontrolled grazing sites was also measured during the two years of the study period using the Veg Measure software. From June to November in2015 and 2016, controlled and uncontrolled livestock grazing sites were grazed on a daily basis by local ewes with a stocking rate of 2 and 1 head ha^(-1) respectively. Results reveal that the organic matter contents of coarse-textured, slightly alkaline soil of the study site were in the range of 9.4-17.6 g kg^(-1) soil and showed a strong positive correlation with aboveground vegetation biomass. The biomass of plants was 56.5% and 33% greater at controlled than uncontrolled grazing site in 2015 and 2016 respectively and plant cover was also higher at controlled than uncontrolled grazing site in both years The nutrient contents were significantly(P<0.05)lower in grasses than shrubs. In both years, the controlled grazing increased the weight gain of ewes about two folds compared to the uncontrolled grazing.The results indicate that controlled grazing improved the v
