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171.
This article makes an assessment of the following key natural resources in the Okavango Delta: arable land, basket-making resources, fish stocks, and river reeds. Non-data-intensive socio-economic indicators (as opposed to conventional data-intensive indicators) of trends in resource prices, trends in labour time for resource extraction, substitution of less preferred commodities, maximum sustainable yield and perceived scarcity were utilized to assess the scarcity of the resources. The study reveals that basket-weaving resources, land for flood recession arable (molapo) agriculture, and river reeds are increasingly becoming scarce in the harvesting areas, whereas fish stocks are still abundant. It is recommended that appropriate policies should be introduced for the management of natural resources. Property rights could be granted to communities to manage natural resources such as fish and veld products in line with the wildlife model for community based natural resources management (CBNRM). In addition, the authors suggest that the Government of Botswana should take the responsibility for allocating land for molapo arable farming in order to make it more accessible.  相似文献   
172.
Women and natural resource management: Illustrations from India and Nepal   总被引:1,自引:0,他引:1  
This article attempts to delineate women's roles in natural resource management by highlighting their roles in management of water, agriculture, livestock, forestry and fishery. The article is based on the findings of case studies in rural areas of India and Nepal done during 2003 and 2004 by the author as well as by other researchers. Taking women as primary respondents, empirical work used participatory techniques, such as in‐depth surveys, focus group discussions and participant observation. Findings suggest that women clearly outdo men in terms of their involvement in use and management of all the studied sectors, i.e., water, agriculture, livestock, forestry and fishery. Yet, they face categorical exclusion and denial of equal sharing of benefits from natural resources. In order to ensure sustainable use of these resources, the article recommends that policy makers, planners and development workers must have a better understanding of the relative and often shifting roles of men and women in natural resource management, including division of labour, access to resources, decision‐making and traditional knowledge and practices. The article concludes with sector‐specific recommendations.  相似文献   
173.
ABSTRACT: Pesticide runoff from dormant sprayed orchards is a major water quality problem in California's Central Valley. During the past several years, diazinon levels in the Sacramento and San Joaquin Rivers have exceeded water quality criteria for aquatic organisms. Orchard water management, via post‐application irrigation, and infiltration enhancement, through the use of a vegetative ground cover, are management practices that are believed to reduce pesticide loading to surface waters. Field experiments were conducted in Davis, California, to measure the effectiveness of these management practices in reducing the toxicity of storm water runoff. Treatments using a vegetative ground cover significantly reduced peak concentrations and cumulative pesticide mass in runoff for first flush experiments compared with bare soil treatments. Post‐application irrigation was found to be an effective means of reducing peak concentrations and cumulative mass in runoff from bare soil treatments, but showed no significant effect on vegetated treatments.  相似文献   
174.
农业生态系统种养结合优化结构模式的研究   总被引:11,自引:0,他引:11  
杨修 《自然资源学报》1998,13(4):344-351
根据种植业和畜禽养殖业协调发展的原则,以河南省封丘县潘店乡现行农业生态系统物质流、能量流和价值流为基础,以种植业和畜禽养殖业总体经济纯效益最高为目标,在土地面积、劳力、畜力、社会需求、饲料量的约束之下,进行了种养结合的优化设计,得出了优化方案。优化后的农业生产结构比优化前的纯收益提高了6914%,系统的综合效益指数提高了3348%,优化方案对调查地区农业生态系统结构调整具有一定指导意义。  相似文献   
175.
讨论了钻井废弃泥浆的最终处置和综合利用方法,提出了一些见解,与为环境保护相关的研究提供了依据。  相似文献   
176.
四川坡耕地水土流失十分严重。沟稻垄杂耕作法是在同一坡地空间实行垄沟植稻,垄上(埂)种植红苕、玉米和豆类等杂粮的一种水土保持耕作方法。据在川中遂宁等地试验、示范、推广,沟稻垄杂耕作法可使坡耕地水份流失量减少96.03%、泥沙流失量减少98.77%;杂粮保产外,每亩坡地可增收稻谷11 1.3kg。本文介绍了沟稻垄杂耕作效益及栽培技术。  相似文献   
177.
通过盆栽试验,研究了伤根对谷子水分利用效率的影响.结果表明,苗期适度伤根能够提高谷子叶片水分利用效率(WUE),而苗期伤根量较严重或拔节期和孕穗期伤根则会降低谷子叶片WUE.在谷子收获期,除TM(高水分条件下,孕穗期中度伤根)和sl(低水分条件下,拔节期轻度伤根)处理外,其余伤根处理的生物量WUE均高于对照.在高水条件下,伤根处理对谷子籽粒产量WUE影响不显著;而在低水分条件下,前期适度伤根能使谷子籽粒产量WUE显著提高,而后期伤根处理的籽粒产量WUE提高不显著.图3表1参11  相似文献   
178.
This Impacts article proposes strategies for mitigating negative impacts of urbanization in rural locations in the United States. Issues addressed include impacts of population growth and development, loss of agricultural lands, and impacts of climate change on agriculture and rural communities. Conclusions are supported by stakeholder survey data, geographic information systems-based data, and desktop reviews of research journal publications. We propose a sustainable, diversified approach that supports mitigation of issues, including increasing demand on food production and decline of rural communities. A key issue that we address is where we will find suitable landscapes to reduce enough food for 9.6 billion people living in 2050.

Urban and rural development planners are grappling with solutions to escalating impacts global populations, stresses on food production, and effects of climate change. Solutions are identified, including strengthening rural and urban contexts by establishing connected and interdependent links that support diversification of rural and urban contexts as viable solutions to these issues.

Diversified rural-to-urban sustainable agriculture production is a promising approach to addressing climate change impacts. Organic agriculture principles exhibit strong diversity and are accredited by United States Department of Agriculture as the only federally certified sustainable agriculture practice in the United States. Sustainable agriculture practices are evolving into profitable diversified alternative food sources. We offer substantiated alternative solutions for remediating impacts of urbanization on rural agriculture and communities. Collectively, these solutions can strengthen symbiotic relationships between sustainable agriculture and rural communities, addressing our growing population issues and preserving our dwindling farmlands and rural communities.  相似文献   

179.
• Bioaerosol emitted from farming and composting facilities may pose health risks. • We describe population characteristics around these sites and infer public concern. • Sites were mapped and overlaid with population, demographic and school data. • Approximately 16% of the population and 15% of schools are located near these sites. • More community health studies need to be conducted around these sites. Bioaerosol exposure has been linked to adverse respiratory conditions. Intensive farming and composting facilities are important anthropogenic sources of bioaerosols. We aimed to characterise populations living close to intensive farming and composting facilities. We also infer whether the public are becoming more concerned about anthropogenic bioaerosol emissions, using reports of air pollution related incidents attributed to facilities. We mapped the location of 1,257 intensive farming and 310 composting facilities in England in relation to the resident population and its characteristics (sex and age), area characteristics (deprivation proxy and rural/urban classification) and school locations stratified by pre-defined distance bands from these bioaerosol sources. We also calculated the average number of air pollution related incidents per year per facility. We found that more than 16% of the population and 15% of schools are located within 4,828 m of an intensive farming facility or 4,000 m of a composting facility; few people (0.01%) live very close to these sites and tend to be older people. Close to composting facilities, populations are more likely to be urban and more deprived. The number of incidents were attributed to a small proportion of facilities; population characteristics around these facilities were similar. Results indicate that populations living near composting facilities (particularly>250 to≤4,000 m) are mostly located in urban areas (80%–88% of the population), which supports the need for more community health studies to be conducted. Results could also be used to inform risk management strategies at facilities with higher numbers of incidents.  相似文献   
180.
近年来,排污权有偿使用与交易制度在中国部分省份开展了试点工作,许多大型的规模化畜禽养殖场也进行了排污许可证的申领。针对新西兰奶牛养殖业的污染治理措施进行了研究,梳理其开展污染防治工作的措施体系,以陶泊湖周边施行的氮排放配额与交易为主要对象,阐述了新西兰在养殖业排放配额与交易制度方面的工作实践,其配额基准核定方法、"资源许可证"申领制度、配额交易体系、相关支撑措施在一定程度上具备优势和先进性,对中国的畜禽养殖污染减排工作具有借鉴意义。  相似文献   
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