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11.
针对目前城市供水价格计算与计量方式不合理和突出的水资源供需矛盾,提出了按全成本水价模式测算广东省城市供水价格,并采用阶梯水价、两部制水价和季节水价计量方式逐步达到全成本水价的措施与实施步骤,确保水资源的持续利用支撑广东省经济社会的可持续发展.  相似文献   
12.
We develop the outlines of a new approach to study the role of nonhumans in constituting ‘implementation’ and calculative–discursive practices in development projects and programs. Developing a framework around the concept of friction (material resistance or recalcitrance encountered in processes of transformation), we analyze an Energy Self-sufficient Village program in Indonesia. Focusing on specific projects and episodes within this program, we identify multiple distinctive instances of friction. These were driven by nonhumans’ (and humans’) resistance, as remolding of development beneficiaries’ practices was attempted by project administrators, government officials, entrepreneurs and by the (scientific) calculations embedded in their policies, strategies and models. In concluding, we distill four ways in which nonhumans relationally shape development practices: (a) by resisting representations and calculations produced by human actors, (b) by re-directing planned/expected courses of action, (c) through biophysical change to their weight or textures as they move in space and time, and (d) by mediating competition for resources. Overall, nonhumans play a central role in making and unmaking asymmetric relations of power in practice and by constituting practices that diverge from prior expectations, problematize linear understandings of ‘policy implementation’. Their material and discursive agency is multiple, manifesting differently in different relational settings, which highlights the importance of broadening the range of spokespersons who speak on behalf of nonhumans and whose voices can be considered reliable and true. Our study thus provides support to calls for pluralizing and democratizing development ‘expertise’ beyond the usual suspects in science, government and civil society.  相似文献   
13.
Meeting the food needs of the growing and increasingly affluent human population with the planet’s limited resources is a major challenge of our time. Seen as the preferred approach to global food security issues, ‘sustainable intensification’ is the enhancement of crop yields while minimizing environmental impacts and preserving the ability of future generations to use the land. It is still unclear to what extent sustainable intensification would allow humanity to meet its demand for food commodities. Here we use the footprints for water, nitrogen, carbon and land to quantitatively evaluate resource demands and greenhouse gas (GHG) emissions of future agriculture and investigate whether an increase in these environmental burdens of food production can be avoided under a variety of dietary scenarios. We calculate average footprints of the current diet and find that animal products account for 43–87% of an individual’s environmental burden – compared to 18% of caloric intake and 39% of protein intake. Interestingly, we find that projected improvements in production efficiency would be insufficient to meet future food demand without also increasing the total environmental burden of food production. Transitioning to less impactful diets would in many cases allow production efficiency to keep pace with growth in human demand while minimizing the food system’s environmental burden. This study provides a useful approach for evaluating the attainability of sustainable targets and for better integrating food security and environmental impacts.  相似文献   
14.
Ecosystem changes currently question the traditional allocation of fishing rights and quotas in the fishery of Northeast Atlantic mackerel and Norwegian spring-spawning herring in the Northeast Atlantic. Variability in the distribution of these highly migratory species escalated in a political conflict between member states of the European Union, Iceland, the Faroe Islands and Norway, which is a driving force for unsustainable fishery. The aim of this paper is to investigate this conflict by outlining the social understandings of diverse stakeholders by using the Q methodology. The method reduced the complexity of numerous opinions, detected four distinct perspectives and simultaneously categorised the participating stakeholders. Although the perspectives differ in various elements, the protection of economic interests seems to dominate over the quest for sustainability. The call of all stakeholders in this study to clarify the fishing rights in the Northeast Atlantic reveals a clear deficiency of the current international fishery management in handling abrupt ecological changes and the necessity to acknowledge this as a complex adaptive system.  相似文献   
15.
There is an increasing need for transformational changes in the global food system to deliver healthy nutritional outcomes for a growing population while simultaneously ensuring environmental sustainability. However, such changes are subject to political and public constraints that usually allow only gradual, incremental changes to occur. Drawing inspiration from the British cycling team’s concept of marginal gains, we show how transformation might be reconciled with incremental changes. We demonstrate that a set of marginal food system changes acting to increase production efficiency, to reduce losses or to adjust diets could collectively reduce the agricultural land required globally for food production by 21%, or over a third given higher adoption rates. The results show that while all categories of action are important, changes in consumer choices in Europe, North America and Oceania and in the supply-chain in Africa and West and Central Asia have the greatest potential to reduce the land footprint of the food system.  相似文献   
16.
珠江三角洲丘陵赤红壤开发中的问题与可持续利用   总被引:1,自引:0,他引:1  
杨恬  朱照宇 《热带地理》2007,27(5):395-399,404
丘陵赤红壤是珠江三角洲社会经济发展的重要土壤资源,但是长期以来的人为干扰和不合理利用使土壤性能退化,生态环境恶化,严重影响了丘陵赤红壤的可持续利用。文中总结了丘陵赤红壤的基本特性及利用现状,探讨其生态环境重建及实现可持续利用的途径。认为丘陵赤红壤面临的主要问题有:水土流失、养分贫瘠、表土砂质化、土壤结构退化、土壤水分性能退化、酸雨和重金属造成的污染等。指出实现其可持续利用的途径主要有:加强水土流失的治理;培育土壤肥力,调节土壤水分;增加生物多样性,建立良好的生态结构;防治"三废"污染,使用清洁能源;发展绿色农业与观光农业。  相似文献   
17.
湖南省桂东县处于边远山区,经济发展水平低,为国家级贫困县。但其自然资源丰富,生态环境质量良好,旅游资源独具特色。通过对边远山区县资源环境特点和经济发展现状的分析,提出了促进地区可持续发展的建议:调整产业结构,在发展超级稻和优质稻基础上,发展具有地方特色的药、菜、茶、果、烟,外加楠竹和园艺的种植业,发展以牛、羊等草食性牲畜为主的养殖业;发展小水电和以电力为基础的电化工业及农产品加工业;发展红色旅游和休闲度假相结合的生态旅游业;加强生态环境保护力度,以促进桂东区域经济的可持续发展。  相似文献   
18.
西部地区资源实现可持续利用的道路初探   总被引:1,自引:0,他引:1  
桓曼曼  陈来卿 《热带地理》2001,21(4):350-353
介绍了我国西部资源的国情,指出资源利用中存在的问题,其原因在于不正确的人与自然观导致了人们对资源的不合理利用;粗放型的经济增长方式;资源的管理体制不完善等等,提出了实现西部地区资源可持续利用的七大对策;转变经济增长方式;依靠科技进步;树立正确的资源观;制定一个系统有效的统一管理体制;全方位的资源综合利用,进行资源核算,实行资产化管理。  相似文献   
19.
汪宇明 《热带地理》2001,21(4):354-359
分析了广西的基本区情条件,揭示了广西区域开发格局的空间变动趋势,提出了广西新世纪实施可持续发展战略的举措,即加强以交通为主的基础设施建设,开发以洪水河为主的水能资源,加快建设成为南中国西南东输的枢纽;调整和优化产业结构,确立主导产业的市场地位,提升优势产业的市场竞争力;加快城乡转型的进程,提高城镇化的水平和质量,控制人口增长、提高人口质量,治理环境污染;制度创新, 优化经济布局的区域结构。  相似文献   
20.
陈朝辉 《热带地理》2001,21(3):202-206,222
三亚市位于海南岛最南部,具有得天独厚的生态环境优势。近20年来,生态环境建设虽取得初步成效,但问题也较突出,如林业尚存隐患,耕地锐减,水域受蚕食和局部环境恶化,城市绿化美化不足等。生态环境建设面临的任务主要是:合理布局城镇,建设具有经济-生态良性循环的城乡体系;完善林业生态体系建设,建成强有力的陆地生态支柱;保护好水体环境,搞好碧水工程建设;保护耕地、保证农业持续发展;整治环境,提高环境质量。为此必须采取相应措施。  相似文献   
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