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61.
浙闽山区茶叶生产基地评价的探讨 总被引:6,自引:0,他引:6
茶叶基地的评价包括对基地的自然和经济条件的评估,应用系统分析方法,将自然和经济条件进行定量的综合评估,用综合评价值区分基地间的差异,最后定性与定量相结合,提出茶叶生产基地的合理布局. 相似文献
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63.
松嫩平原是中国内陆湿地集中分布区之一。该区湿地类型有沼泽、湖泊、盐沼和稻田,此外还有水库和少量泥炭地。概述了该区湿地的研究现状,并指出目前研究热点。重点探讨了未来本区湿地的研究趋势,主要体现在湿地生态系统结构、功能和过程研究,湿地的区域生态功能评价,湿地污染及其治理,退化湿地恢复和重建,湿地多样性与湿地保护,湿地资源综合利用,湿地对全球变化响应和全球变化对湿地影响,湿地-草地-盐碱地转换机制和过程和驱动力等方面。 相似文献
64.
国外城市群经济联系空间研究进展 总被引:28,自引:1,他引:28
城市群经济联系的复杂性空间规律已经成为城市地理学、区域地理学、经济地理学研究的重点范畴。现代意义的城市群经济联系空间发展研究始于50年代,城市群体化现象大规模出现,城市化进程迅速发展的时期。经过二战前的启蒙发展、二战后-60年代的初步发展、70-80年代的丰富深化、90年代的全面发展阶段,50多年来城市群空间研究领域不断深化、研究队伍不断壮大、研究成果不断涌现、研究范式不断丰富,呈现多视角、多层次、多尺度,理论与实证、定性与定量相结合的研究体系,研究内容上文章着重对国外大都市区、都市带等城市群经济联系的空间组织与结构研究进行总结,并指出当前研究的热点与焦点。 相似文献
65.
With the regional population growth, socioeconomic development, more and more attention has been paid to issues on the shared water allocation and the transboundary eco-security conservation during the development of water resources in the international rivers. In this paper, the existing major problems on transboundary waters in different sub-regions of Asia, such as water shortage, transboundary waters pollution, fragile eco-environment are discussed. Then, the key scientific issues to be concerned in the next study progress on the basis of the analyses of the new research directions and focus fields are raised: (1) unpredicted changes of the hydrologic and water system, and their impacts on the allocation of the sharing waters by global changes; (2) models of the international cooperation on the international rivers on the studies of international and national water laws or regulations, policies, the relative experiences and the case studies; (3) quantificational assessment on environmental flow, available water, and the comprehensive functions and values of the international watercourse system; (4) studies on transboundary aquatic bio-diversity maintenance, transboundary pollution supervision and treatment under the rules and principles accepted by the riparian states; (5) issues on transboundary compensation at the rules of “payments for using”, “payments for harm” and “compensation for benefit”; (6) using advanced 3S techniques to promote the integrated watershed development and management; and so on. 相似文献
66.
Managing sustainable farmed landscape through 'alternative' food networks: a case study from Italy 总被引:1,自引:0,他引:1
LEWIS HOLLOWAY ROSIE COX† LAURA VENN‡ MOYA KNEAFSEY‡ ELIZABETH DOWLER§ HELENA TUOMAINEN§ 《The Geographical journal》2006,172(3):219-229
This paper focuses on a case study of an 'alternative' food network based in the Abruzzo National Park, Italy, to explore how ideas of sustainable farmland management can be expressed through broader understandings of developing networks of care concerned with local economies and societies, high-quality specialist food products, particular 'traditional' farming practices and livestock breeds, as well as the ecology of a farmed landscape. The scheme allows customers, internationally as well as in Italy, to 'adopt' a milking sheep on a large mountain farm. In return, adopters are sent food products from the farm. The adoption scheme is inter-twined with an agri-tourism project which provides accommodation, runs a restaurant and engages in educational activities. The scheme is the result of the individual initiative of its founder, and is associated with a strongly expressed ethical position concerning the value of sustaining valued local rural landscapes and lifestyles, and the importance of 'reconnecting' urban dwellers with rural areas, farming and 'quality' food production. Yet the localness of the scheme is sustained through wider national and international networks: volunteer and paid workers are drawn from several European countries, funding has been acquired from the EU LEADER programme, and internet and transport technologies are essential in connecting with and supplying an international customer base. The broader economy of care instanced in this case study draws attention to a need to develop strategies for sustainable farmland management constructed around wider programmes of social, economic and cultural, as well as environmental, concern. 相似文献
67.
Jin-Yong Lee Jeong-Yong Cheon Hyung-Pyo Kwon Hee-Sung Yoon Seong-Sun Lee Jong-Ho Kim Joung-Ku Park Chang-Gyun Kim 《Environmental Geology》2006,51(4):581-593
Attenuation characteristics of landfill leachate were examined for two uncontrolled landfills in Korea. The two landfills containing municipal wastes without appropriate bottom liner and leachate treatment system have different landfill age, waste volume, and most importantly different hydrogeologic settings. One landfill (Cheonan landfill) is situated in an open flat area while the other (Wonju landfill) is located in a valley. Variations of various parameters including dissolved organic carbon (DOC), dissolved oxygen (DO), alkalinity, pH, electrical conductivity (EC), redox potential (ORP), ammonia (NH3), nitrate (NO3−), sulfate (SO42−), and chloride (Cl−) were examined along groundwater flow path. All these parameters were analyzed every month for a year. In the interior of the landfills, typical anaerobic conditions revealed by low DO and NO3 concentrations, negative ORP values, high NH3, alkalinity, and Cl− concentrations were observed. Generally, higher levels of contaminants (DOC, NH3, and Cl−) were detected in the dry season while they were greatly lowered in the wet season. Significantly, large decrease of Cl- concentration in the wet season indicates that the dilution or mixing is one of dominant attenuation mechanisms of leachate. But detailed variation behaviors in the two landfills are different and they were largely dependent on permeability of surface and subsurface layers. The intermediately permeable surface of the landfills receives part of direct rainfall infiltration but most rainwater is lost to fast runoff. The practically impermeable surface of clayey silt (paddy field) at immediately adjacent to the Cheonan landfill boundary prevented direct rainwater infiltration and hence redox condition of the ground waters were largely affected by that of the upper landfill and the less permeable materials beneath the paddy fields prohibited dispersion of the landfill leachate into down gradient area. In the Wonju landfill, there are three different permeability divisions, the landfill region, the sandy open field and the paddy field. Roles of the landfill and paddy regions are very similar to those at the Cheonan. The very permeable sandy field receiving a large amount of rainwater infiltration plays a key role in controlling redox condition of the down gradient area and contaminant migration. This paper reports details of the attenuation and redox conditions of the landfill leachates at the two uncontrolled landfills. 相似文献
68.
69.
通过对向斜洼地含水层水文地质特征的勘探及研究,对研究区的水文地质边界条件进行了概化,并用水均衡法估算了地下水资源量,对拟建一级电站引水渠沿线提取地下水进行融冰的可行性进行了研究,并提出了取水方案. 相似文献
70.
时域反射技术在地学研究中的应用 总被引:5,自引:0,他引:5
综合介绍了时域反射技术在地学研究中的应用。包括时域反射仪的工作原理、测量参数(特征阻抗、介电常数、土壤含水量、土壤电导率)、时域反射探针技术以及时域反射技术在农业地质、水文地质、灾害地质等研究中的应用与进展。 相似文献