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曹振, 胡克, 张永光, 介冬梅, 赵亮   总被引:7,自引:2,他引:5  
 通过对地表沉积物的粒度分析,研究了科尔沁沙地四种主要土地类型地表沉积物的粒度分布特征;结合该地区多年气候状况,对不同土地类型的可风蚀性进行了定量研究;分析了不同土地类型的潜在可风蚀性。同时,对玉米地、谷子地等七种农作物种植地的表土做了粒度分析,认为不同农作物对地表可风蚀性的影响较小。  相似文献   

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彭珂珊 《热带地理》1994,14(2):143-151
长期以来,由于忽视了人口、土地、粮食与灾害系统内各因素的相互协调,人类的生存与发展基本问题越来越多地摆在我们面前,致使在人口增长过快情况下,产生了土地资源质减量退,粮食生产徘徊不前,自然灾害频繁发生等危害生国计的社会问题,在跨入21世纪的关键时期,如何采取有力措施解决上述问题,已为90年代的重要任务,针对针中国国际本文分析了人口,土地,粮食,灾害相互间的关系,进而提出了相应之对策。  相似文献   

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ABSTRACT

In academic and policy discourse, the concept of urban resilience is proliferating. Social theorists, especially human geographers, have rightfully criticized that the underlying politics of resilience have been ignored and stress the importance of asking “resilience of what, to what, and for whom?” This paper calls for careful consideration of not just resilience for whom and what, but also where, when, and why. A three-phase process is introduced to enable these “five Ws” to be negotiated collectively and to engender critical reflection on the politics of urban resilience as plans, initiatives, and projects are conceived, discussed, and implemented. Deployed through the hypothetical case of green infrastructure in Los Angeles, the paper concludes by illustrating how resilience planning trade-offs and decisions affect outcomes over space and time, often with significant implications for equity.  相似文献   

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Conference AnnouncementsSpecialized Conference

Contaminated aquatic sediments: Historical records, environmental impact, and remediation, Milwaukee, USA, June 14–16, 1993  相似文献   

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黄土高原人口,资源,环境与经济发展的协调   总被引:1,自引:0,他引:1  
文章阐述了黄土高原人口,资源,环境与经济发展存在的,综合分析了协调的可靠性,探讨了协调的一般模式,提出了实现黄土高原人口,资源、环境与经济发展协调的措施和途径。  相似文献   

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郝成元, 吴绍洪, 杨勤业   总被引:13,自引:8,他引:13  
 依据野外调查和遥感动态监测结果,对毛乌素地区的土地利用与沙漠化过程的发展及其防治进行了研究。结果表明,该地区20世纪80年代中期和90年代末轻度以上沙漠化土地面积分别占土地总面积的85.98%和86.07%,沙漠化土地的总面积略有增加,总体趋于稳定;但沙漠化程度加重,重度以上的沙漠化土地面积在总土地面积中增加了3.6%;沙漠化发展的重要原因之一就是人类不合理的土地利用方式。不合理土地利用方式及土地利用方式的改变,使以风沙活动为主导外营力的沙漠化过程得以发展。最后,根据毛乌素地区沙漠化过程与土地利用之关系,提出了研究区防治土地沙漠化应调整农业结构和土地利用方式的建议。  相似文献   

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西部大开发的重大意义与新观念,新思路,新举措   总被引:6,自引:1,他引:5  
本文简要论述了西部大开发的意义,提出实施西部大开发战略要树立长期发展观、市场经济观、可持续发展观及人本发展观;强调指出西部开发应有新的思路,新的举措-基础超前,公路为先,水为重点;生态为本,保护性开发,可持续发展;结构优化,科学导向,合理转移;重点突破,阶段推进,因地制宜;规范政策,理顺体制,创新机制。  相似文献   

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中,俄,朝之间的图们江地区下面临合作开发,而运输合作是当前最现实的工作。俄朝港口开发潜力大,目前运力严重剩余,迫切要求中国物流的增长。本文通过对港口条件和物流走向的分析,指出运输合作中存在的障碍以及史服障碍的前景。  相似文献   

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王跃  董光荣 《中国沙漠》1995,15(1):42-48
根据对麻扎塔格山的考察以及样品分析,指出这一地区有厚层的下更新统存在,它的底界约为2.5MaB.p.。麻扎塔格山可做为塔里木盆地第三系、第四系分界线的典型地点。通过这一发现从而确定了该山的隆起时代、形式与幅度,对麻扎塔格山隆起前后的以及隆起后的地质,地理意义也做了初步讨论。  相似文献   

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陈钧  黎军 《中国沙漠》1994,14(3):83-85
靖远、会宁、固原地处我国黄土高原的西部半干旱干草原生态环境,植被稀疏,生态环境脆弱,动物种类亦较为贫乏。根据自然环境、啮齿动物种类和分布的情况,该区大致可分为四个生态地理型──森林灌丛、干草原、荒漠草原和农田。  相似文献   

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Crime is both a factual and perceptual component of the urban landscape, seemingly both a societal pathology and the consequence of economic disparity between social groups. Crime has a spatial structure that can be revealed by mapping. Urban crime has a spatial multiplier effect that changes the values and perceptions of how people see urban space, and which jeopardizes the quality of life of a city's inhabitants. In this research we examine the question of whether the geography of actual criminal acts is echoed by peoples' perceptions of crime, what might be termed their “spaces of fear”. We ask how the fear of crime is associated with reported urban crime. Urban crime incidents have been increasing in Viçosa, Minas Gerais, Brazil. We assembled crime information about Viçosa from two sources: first, crime as reported to the police and second, crime as perceived by city residents and measured by surveys and interviews. Reported criminal acts reveal a clustered geography, focusing particularly on the Downtown area, where there is a concentration of urban wealth and potential victims are more numerous. Offenses against property were focused on Downtown, while offenses against the person were located mostly in peripheral areas. The widespread feeling of insecurity in the city's neighborhoods, reflecting the fear of becoming a victim of violence and crime, was common throughout the city. Results confirmed the conclusion of past studies showing that the fear of violence and crime are not directly related to increasing numbers of criminal reports. Sites with higher incidence of crimes are not places with higher levels of fear. Rather than being geographically explainable “spaces of fear”, the spatial distribution of the fear of violence and crime appears to be unrelated in Viçosa, and neither is clustered or dispersed in any measurable way.  相似文献   

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