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Communities in Tigray, Northern Ethiopia, have established exclosures on formerly degraded grazing lands and other land uses to promote natural regeneration of plants. Village bylaws devised by communities govern the management of exclosures. We analysed the effectiveness of village bylaws that are used to manage exclosures in addressing forest degradation, resolving conflicts among users over natural resource use, and meeting high expectations of users to realise economic benefits from exclosures through enhancing revenue from sale of grass and dry wood. We collected data using qualitative methods during July and November 2008 in two villages of Tigray. The village bylaws mitigated forest degradation by facilitating users to have common goals in the management of exclosures, and resolved conflicts among users by using monetary sanctions including penalties. The village bylaws were not effective in meeting the high expectations of users to realise economic benefits from exclosures. In some cases, the enforcement of village bylaws was constrained by high social capital, which resulted in the negligence among users in exposing free riders. This indicates that high social capital does not always enhance communal resource management. Moreover, recurrent drought, shortage of fuel wood, and the growing number of landless youths in both villages constrained the effectiveness of village bylaws and further expansion of exclosures. Village committees should focus on addressing the low level of rule enforcement and minimise negligence among users of exclosures through developing a sense of responsibility among users rather than focusing on penalties.  相似文献   
2.
Wood charcoal production provides affordable energy in many developing countries and has substantially contributed to the economy through the provision of rural incomes. In several countries, charcoal production leads to overexploitation of forests due to inefficiencies in processing. This study was undertaken in central Laos to (1) examine and document traditional charcoal production systems; (2) investigate the production capacity, recovery efficiencies and economic gains of existing traditional charcoal production methods; (3) characterize the chemical properties of wood charcoal and investigate the potential for soil restoration and (4) investigate local charcoal producers' perception on forest degradation and their species preferences. Through a socio-economic survey, a cost-based method for economic valuation was undertaken on a range of charcoal production methods currently being used. Laboratory chemical analyses were performed on wood charcoal samples. Results indicated that the traditional mud charcoal mound was used by the majority (82%) of charcoal producers. Total charcoal production per production cycle varied between 400 (produced from 2.7 m3 of wood) and 1600 kg (produced from 18 m3 of wood), with a mean of 938 kg (±120) for traditional mud charcoal mounds. The volume of the traditional mud charcoal mounds correlated positively and significantly with total charcoal production (R 2 = 0.45, p?=?0.03), whereas correlated negatively and significantly with the recovery efficiency (R 2 = 0.58, p?=?0.01). On average, the local producers receive a total net benefit of 457,272 Lao kip (USD 57.2) in 17 days. We also identified a rice husk mound method of charcoal production, which may not encourage further deforestation while producing rice husk biochar that can be used for soil restoration. Furthermore, we found that there are significant differences (p < 0.05) between the sampled wood charcoals in chemical properties, indicating that the potential of using wood charcoal for the restoration of degraded soils varies from charcoal to charcoal.  相似文献   
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Earlier studies on land change (LC) have focused on size and magnitude, gains and losses, or land transfers between categories. Therefore, these studies have failed to simultaneously show the complete LC processes. This paper examines LCs in the Legedadie-Dire catchments in Oromia State, Ethiopia, using land-category maps with intensity analysis (IA) at three points in time. We comprehensively analyze LC to jointly encompass the rate, intensity, transition, and process. Thirty-meter US Geological Survey (USGS) Landsat imagery from 1986, 2000, and 2015 (<?10% cloud) is processed using TerrSet-LCM and ArcGIS. Six categories are identified using a maximum likelihood classification technique: settlement, cultivation, forest, water, grassland, and bare land. Then, classified maps are superimposed on the images to statistically examine changes with an IA. Considerable changes are observed among categories, except for water, between 1986–2000 and 2000–2015. Overall land change occurred quickly at first and then slowly in the second time interval. The total land area that exhibited change (1st?≈?54% and 2nd?≈?51%) exceeded the total area of persistence (1st?≈?46% and 2nd?≈?49%) across the landscape. Cultivation and human settlements were the most intensively increased categories, at the expense of grassland and bare ground. Hence, when grassland was lost, it tended to be displaced by cultivation more than other categories, which was also true with bare land. Annual intensity gains were active for forest but minimal for cultivation, implying that the gains of forest were associated with in situ reforestation practices and that the gains in cultivation were caused by its relatively large initial area under a uniform intensity concept. This study demonstrates that IA is valuable for investigating LC across time intervals and can help distinguish dormant vs. active and targeted vs. avoided land categories.  相似文献   
4.
Environmental Management - Research results published regarding the impact of soil and water conservation practices in the highland areas of Ethiopia have been inconsistent and scattered. In this...  相似文献   
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Environment, Development and Sustainability - Sustainable agriculture focuses using agricultural resources with minimum possible negative environmental externality to produce more food. The present...  相似文献   
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