Rangeland degradation has been identified as a serious concern in alpine regions of western China on the Qinghai-Tibetan plateau (QTP). Numerous government-sponsored programs have been initiated, including many that feature long-term grazing prohibitions and some that call for eliminating pastoralism altogether. As well, government programs have long favored eliminating plateau pikas (Ochotona curzoniae), assumed to contribute to degraded conditions. However, vegetation on the QTP evolved in the presence of herbivory, suggesting that deleterious effects from grazing are, to some extent, compensated for by reduced plant-plant competition. We examined the dynamics of common steppe ecosystem species as well as physical indicators of rangeland stress by excluding livestock and reducing pika abundance on experimental plots, and following responses for 4 years. We established 12 fenced livestock exclosures within pastures grazed during winter by local pastoralists, and removed pikas on half of these. We established paired, permanent vegetation plots within and outside exclosures and measured indices of erosion and biomass of common plant species. We observed modest restoration of physical site conditions (reduced bare soil, erosion, greater vegetation cover) with both livestock exclusion and pika reduction. As expected in areas protected from grazing, we observed a reduction in annual productivity of plant species avoided by livestock and assumed to compete poorly when protected from grazing. Contrary to expectation, we observed similar reductions in annual productivity among palatable, perennial graminoids under livestock exclusion. The dominant grass, Stipa purpurea, displayed evidence of density-dependent growth, suggesting that intra-specific competition exerted a regulatory effect on annual production in the absence of grazing. Complete grazing bans on winter pastures in steppe habitats on the QTP may assist in the recovery of highly eroded pastures, but may not increase annual vegetative production.
The Gobi Gurvansaikhan National Park was established in south central Mongolia in 1993 and is used by over 1100 families with pastoralism as their main means of livelihood. Research conducted in 1998–2000 to analyse grazing management problems identified a number of issues and concerns, including a significant increase in the number of herders and the size of the herd; variations in herd size reflecting differences in wealth; problems with marketing of livestock or livestock products; declining stock movements because of transportation costs and loss of water sources; and significant competition and conflicts for grazing areas. The socio‐economic problems associated with Mongolia's transition to a market system, coupled with the expansion of protected areas, mean that herders have to adapt to both the current economic system and changes in land use. Although some aspects of the development of the park can be seen as a positive influence on maintaining pastoral livelihoods in this area, the national goal of protecting 30 per cent of the country, doubling the area of Mongolia currently under protected area status, could have negative effects on pastoral livelihoods, unless ministry officials, protected area administrators and pastoralists can work effectively to solve resource problems.
The influence of different range rehabilitation methods on honey mesquite control, herbage production, and grazing capacity were evaluated on a depleted clay loam range site in west Texas. Mesquite control by foliar application of 2,4,5-T + picloram, shredding, mechanical grubbing, mechanical grubbing and seeding to kleingrass, and mechanical grubbing and vibratilling increased herbage production and grazing capacity. Shredding increased soil cover by adding plant litter, but significantly controlled mesquite competition for only 2 years. Seeding to kleingrass resulted in a productive stand with a high estimated grazing capacity. Foliar spraying doubled grass production compared to no treatment and resulted in 76% mesquite mortality 3 years after treatment. Deferment from grazing was important in increasing herbage production during the study period; however, for maximum grazing capacity both mesquite control and proper grazing would be necessary.
G obi Gurvan Saikhan National Conservation Park is an area of stark, natural beauty and an invaluable natural and cultural resource. To visit this area is much like going back in time with pastoralists herding their livestock with methods similar to Chinggis Khan's era. Snow leopards, wolves, argali, and Ibex still roam the mountains and thousands of gazelle graze the steppe. During the summer of 1998 we examined the park's rangelands and visited with the pastoralists almost daily gathering information for a conservation plan to benefit the park and the pastoralists utilizing the park. Park Overview Gobi Gurvan Saikhan National Conservation Park is one of Mongolia's 35 protected areas. It was established in 1993 on the recommendations of Mongolian conservationists and the World Wildlife Fund. The park is approximately 5.68 million acres or more than twice the size of Yellowstone National Park and is located in south central Mongolia in the Omnogobi a i m a g (Mongolia's 21 a i m a g s are like states or provinces). Since Mongolia passed its Protected Areas Law of 1994, the country has greatly expanded the amount of land with protected area designation; by late 1997 there were 39 million acres or about 11% of the country in protected areas. There are four types of protected area designations: Strictly Protected Areas, National Conservation Parks, Nature Reserves, and Monuments. Each is managed by the Protected Area Bureau
Service, Helena, MT. Residue analyses were conducted by Russell Leu at Montana State University Pesticide Laboratory under the direction of Laszio Torma.Herbicides were applied to replicated treatment plots at four sites in west-central Montana with light to moderate spotted knapweed (Centaurea maculosa Lam.) infestations. Plant community diversity was determined for two seasons before the herbicide treatments; diversity measurements have been completed for 2 years after the year of spraying. Although knapweed suppression was high, the communities were not converted to grass monocultures. Herbicidecaused depressions in community diversity measurements were small and transitory. Tordon-treated and Curtail-treated plots showed a small 1-year postspray decline. Diversity on those treatments began to increase relative to the untreated plots during the second postspray growing season. Stinger had the least effect on diversity. No large declines in diversity were caused by these herbicide treatments, and the small depressions were probably transitory. Community response data collected from a limited set of pilot study plots suggested that the herbicide treatments had increased diversity by 3 years postspray.Only small amounts of herbicide were leached below 25 cm. Herbicide residuals in the soil at the 25to 50-cm depth increment were generally undetectable and did not exceed 26 parts per billion at 30 days, trace after 1 year, and none were detected after 2 years. The use of trade or firm names in this publication is for reader information and does not imply endorsement by the U.S. Department of Agriculture of any product or service.
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