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41.
人地关系与脆弱带的研究   总被引:13,自引:2,他引:11  
孙武 《中国沙漠》1995,15(4):419-424
兴起于80年代后期的生态脆弱带研究,标志着"持续发展"的现代人地关系理论对人类生存环境哲学思考的深化。侧重于植物生态领域的脆弱带概念现已被拓宽,生态学、人口承载力、害灾学、荒漠化成为其四个主要的研究方面;由人地关系矛盾所决定的性质的不稳定性为脆弱带的主要特征;界面性、波动性、基质性是脆弱带的主要成因类型。  相似文献   
42.
IINTRODUCTIONInthepast,thesedimenttransportisconsideredinmostengineeringproblemsbecauseofitssignificanteffectonreservoir,navigation,floo'dingcontrolandstabilityofcoastallines(Xuetal.,1992;Heetal.,1997).Inrecentyears,impactsofsedimentontheecologicalhabitatshavebeennotedbymanyenvironmentalists(Klaus,1997).Itseemsthattheconceptofsedimenthazardsorsedimentimpactsmustbeextendedandtheenvironmentalorecologicalimpactmustbeincludedinanycomprehensiveassessment.Forexample,thelarge-scaleconstructiono…  相似文献   
43.
丁敏  杜军  肖天贵 《冰川冻土》2020,42(3):1046-1056
利用1979 - 2018年羌塘国家级自然保护区边缘的3个气象站点狮泉河(西部)、 申扎(中部)和安多(东部)的观测气温(OT), 与ERA-Interim(ET)、 NCEP/NCAR(NT1)、 NCEP/DOE(NT2)和JRA-55(JT)4种再分析气温资料, 从年际变化和年变化两方面采用多年气温变化趋势、 均方差、 相关性等参数方法在羌塘自然保护区进行了适用性研究。结果表明: 从多年平均气温年际变化来看, 4种再分析资料在狮泉河(西部)的适用性较差, JRA-55资料在安多(东部)和申扎(中部)的适用性较好, 且冬季再分析气温资料与观测气温的相关性好于夏季; 从多年平均气温年变化来看, 均表现为冬季(1月或12月)最低, 夏季(7月或8月)最高的“单峰型”变化。综合来看, JRA-55资料在羌塘自然保护区的适用性较好, ERA-Interim对多年气温趋势变化表现不准确, NCEP/NCAR和NCEP/DOE与观测气温相比显著偏低。  相似文献   
44.
Water content and movement in soil profile and hydrogen isotope composition (δD) of soil water, rainwater, and groundwater were examined in a subalpine dark coniferous forest in the Wolong National Nature Reserve in Sichuan, China, following rainfall events in 2003–2004. Light rainfall increased water content in the litter and at soil depth of 0–80 cm, but the increased soil water was lost in several days. Heavy rainfall increased soil water content up to 85% at depths of 0–40 cm. Following the light rainfall in early spring, the δD of water from the litter, humus, illuvial, and material layers decreased first and then gradually reached the pre‐rainfall level. In summer, light rainfall reached the litter humus, and illuvial layer, but did not hit the material layer. Heavy rainfall affected δD of water in all layers. The δD of soil interflow slightly fluctuated with rainfall events. The δD of shallow groundwater did not differ significantly among all rainfall events. Light rainfall altered the shape of δD profile curve of water in the upper layer of soil, whereas heavy rainfall greatly affected the shape of δD profile curve of water in all soil layers. Following the heavy rainfall, preferential flow initially occurred through macropores, decayed plant roots, and rocks at different depths of soil profile. With continuing rainfall, the litter and surface soil were nearly saturated or fully saturated, and infiltration became homogeneous and plug‐like. Forest soil water, particularly in deeper soil profile, was slightly affected by rainfall and, thus, can be a source of water supply for regional needs, particularly during dry seasons. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
45.
In an era of late capitalism and climate crisis, an expanding, heterogeneous network of people find themselves precariously positioned at the edge of disaster. This paper explores how Stop FEMA Now, a coalition of U.S. flood disaster survivors and other coastal homeowners, used social media to challenge neoliberal policies that produced – and then privatized – environmental risk. I find that social media played a crucial and sometimes unexpected role in enabling activists to organize across difference and cohere around an identity that emphasized their multiple layers of vulnerability and responsibilization. Through images that reembedded natural disasters in their political and economic contexts, activists exposed their historic and ongoing abandonment by neoliberal policies and state failures. Ultimately, such abandonments forfeited coastal homeowners to a future marked by fiscal and climate crisis, constituting them as sacrificed citizens. And yet, I also propose that the struggles of sacrificed citizens offer new possibilities for coalitions and pluralisms.  相似文献   
46.
在紧邻大都市的上海九段沙湿地国家级自然保护区上沙实验区范围内,根据地形地势,潮沟水系走向,因地制宜规划设计一个5km2环保低碳,具有湿地保育、监督管理、科学研究和宣传教育于一体的多功能湿地生态科普园,让久居城市的人们远离喧嚣,营造一种宁静清幽、寓教于乐、回归大自然的亲切感。从设计目标、原则、理念和总体布局等方面阐述了九段沙湿地生态科普园的建设思路,为生态、低碳、环保、科学建设九段沙湿地生态科普园提供参考。  相似文献   
47.
Most world natural heritage sites are designated partly by reason of their prominent aesthetic values in accordance with Article Ⅶ of World Natural Heritage Convention.In this paper, the aesthetic values of Kanas National Nature Reserve, which has potential for such designation, was analyzed quantitatively using scenic beauty estimation(SBE).The landscapes of 19 representative scenic spots in the Kanas National Nature Reserve in summer and autumn were selected as the objects of evaluation.The contributions of different landscape factors to the aesthetic value of the Kanas National Nature Reserve were revealed using a multivariate quantitative model.The main factors affecting the aesthetic value were waterscapes, vegetation, mountains, folk culture and the tourist environment.The t-test and F-test results are extremely significant.According to the results, some suggestions were given for conserving the landscapes in the Kanas National Nature Reserve.  相似文献   
48.
依据黑龙江省三江国家级自然保护区内11个村屯310户的问卷调查数据,采用Logistic模型对影响农户参与湿地旅游意愿的影响因子进行定量分析。结果表明,农户参与湿地旅游的意愿受内、外部综合因素影响,户主年龄、对旅游的认知程度、拥有投资资金的量、增加就业机会、提高当地收入、农户参与的可行性、旅游资源情况和当地政府态度是主要的影响因素。针对农户最关心的问题和主要影响因子,提出了考虑农户的经济利益、建立完善的社区参与管理模式、科学规划等促进农户参与湿地旅游措施。  相似文献   
49.
通过对黑龙江省扎龙湿地自然保护区自然资源状况和火灾特点的分析,结合当地社会经济及环境中存在的问题,为研究地区的林火管理提出具体建议。研究表明,在防火季节,有效地控制火源,提高当地居民的防火意识是预防火灾的关键;此外,保证保护区水源供应在火灾预防中起着关键作用。研究结果可为湿地类型自然保护区的林火管理提供参考。  相似文献   
50.
九寨沟保护区植被景观变化与生境破碎化研究   总被引:3,自引:0,他引:3  
根据1974、1994和2002年三个时段卫星影像,将土地覆盖类型划分为针叶林、针阔叶混交林、落叶阔叶林、灌丛、草地、裸地和水体7个类型。研究发现,九寨沟森林面积、特别是针叶林面积减少,各景观类型破碎化程度也在增大。与1974~1994年间森林丧失平均速率相比,1994~2002年间森林丧失速率明显放缓。第二期灌丛面积平均增长速率是第一期的3.5倍。随着生境破碎化的加剧,许多珍稀保护生物的前景变得难以预测,应以审慎的态度来对待所谓的“生态旅游”。  相似文献   
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