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Arable land in Bhutan is under serious threats of land degradation. Proper land management approach is needed to control soil erosion problems. This study is an attempt to characterize and document the conventional and the community-based land management approaches, applied in Chukha and Dagana districts, respectively. The study tried to make a comparative assessment of their social, economic and environmental impacts on the participating farmers. Farmers’ level of participation in the program, implementation of the soil erosion control measures (SECM) and subsequent social, economic and environmental impacts were found to be significantly influenced by the type of approach applied. The study found that community-based approach is by any means better suited for the study sites than the conventional approach. The social, economic and environmental attributes of respondents from the community-based approach were found to have improved significantly as compared to the conventional approach. The community-based approach was thus found to have a higher potential to meet the diverse requirements of rural subsistence farming communities in Bhutan than the conventional approach.  相似文献   
53.
Migratory pastoralism is an adaptation to a harsh and unstable environment, and pastoral herders have traditionally adapted to environmental and climatic change by building on their in-depth knowledge of this environment. In the Hindu Kush Himalayan region, and particularly in the arid and semiarid areas of northern Pakistan, pastoralism, the main livelihood, is vulnerable to climate change. Little detailed information is available about climate trends and impacts in remote mountain regions; herders’ perceptions of climate change can provide the information needed by policy makers to address problems and make decisions on adaptive strategies in high pastoral areas. A survey was conducted in Gilgit–Baltistan province of Pakistan to assess herders’ perceptions of, and adaptation strategies to climate change. Herders’ perceptions were gathered in individual interviews and focus group discussions. The herders perceived a change in climate over the past 10–15 years with longer and more intense droughts in summer, more frequent and heavier snowfall in winter, and prolonged summers and relatively shorter winters. These perceptions were validated by published scientific evidence. The herders considered that the change in climate had directly impacted pastures and then livestock by changing vegetation composition and reducing forage yield. They had adopted some adaptive strategies in response to the change such as altering the migration pattern and diversifying livelihoods. The findings show that the herder communities have practical lessons and indigenous knowledge related to rangeland management and adaptation to climate change that should be shared with the scientific community and integrated into development planning.  相似文献   
54.
As more people visit natural areas for tourism and recreation purposes, it is becoming increasingly important to understand the value they place on these natural resources. Specifically, tourists to Florida have been increasingly interested in visiting natural areas, forests, parks, and preserves-highlighting the importance of this new and growing phenomenon. We analyze visitors' demand for nature-based recreation in the Apalachicola River region of Florida using the travel cost method. The results from a count data regression model reveal that on average visitors would pay 74.18 dollars per visit-day for nature-based recreation resulting in a total economic value of 484.56 million dollars attributable to nature-based recreation in the Apalachicola River region. Results of this study provide useful information for natural resources management in the region and a rationale to preserve Florida's unique ecosystems.  相似文献   
55.
Carbon (C) and nitrogen (N) play an important role in the restoration of ecosystem functions of reclaimed mine soils (RMSs). Postreclamation land use in RMSs affects soil C and N pools and fluxes. We compared the effects of 28-yr-old postreclamation land uses (forest, hay, and pasture) on selected chemical properties of soil, and C and N pools in reference to undisturbed forest and moderately disturbed agricultural land use in southeastern Ohio. The electrical conductivity was higher in RMSs under hay than that in pasture and forest land uses. The RMSs under pasture, hay, and forest had moderately acidic, neutral to slightly alkaline, and slightly alkaline pH, respectively. In the 0- to 5-cm soil depth, soil organic C (SOC) was higher in RMSs under pasture by 99% and under hay by 52% over that under forest. Similarly, total nitrogen (TN) was higher in RMSs under pasture by 98% and under hay by 43% over that under forest. Aggregate-associated SOC concentration in the 0- to 5-cm depth decreased in the order of RMSs under hay > RMSs under pasture > RMSs under forest. The SOC pools in the 0- to 30-cm depth decreased in the order of RMSs under hay = RMSs under pasture > RMSs under forest = undisturbed forest = agriculture land use. Nitrogen pools followed a similar trend. Hay land use has a better potential for improving soil quality in RMSs by enhancing chemical properties and SOC and TN pools than forest or pasture land uses.  相似文献   
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