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生态系统为人类提供了必要的服务,其中大部分是没有市场价格的,因此被认为是"自然的免费赠品"而被大量使用。近年来由于快速的工业化和城市化,不断增长的人口已经使人们认识到生态系统服务也是有限的。环境退化是用来描述生态系统服务的损失或损害的常用指标,而移民往往是环境恶化的后果。那么,生态系统服务退化到什么程度才足以导致人们搬迁?本文通过对移民和环境退化相关文献的综述,力求寻求及时监测生态系统退化状况、避免人类承受生态移民痛苦、探求不同环境下人类更好地生存与发展的途径。  相似文献   

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Interviewers presented 400 residents of Pinellas County, Florida, with sets of hypothetical hurricane threats to assess the effect of hurricane probability forecasts and other risk indicators on public response to the threats. Evacuation notices from local officials were more important than other threat variables, and hurricane probabilities did little to modify that effect. Respondents appeared to comprehend and use the probability information reasonably. Evacuation behavior in actual hurricane threats is consistent with the survey findings.  相似文献   

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火因子是生态系统中重要的干扰因素,对生态系统格局与过程有着深远的影响。采用人为放火的方法研究了草原化荒漠草本层片植物物种丰富度、地上部生物量、植物多度以及高度等群落学特征对火因子的响应。结果表明,火烧后两年(2008—2009年),火烧样地单位面积中草本层片植物物种丰富度有所降低;植物多度多于对照样地,但无显著性差异(P>0.05)。火烧后当年,火烧样地中草本植物地上部生物量显著高于对照样地(P<0.05),第2年地上部生物量无显著性差异(P>0.05),说明火烧后当年有利于提高荒漠生态系统生物生产力,而第2年该效应消除。火烧后当年,研究区3种主要草本植物多根葱、无芒隐子草和茵陈蒿的高度受到了抑制,第2年其高度较对照样地又有所增长,但另一主要植物刺蓬则与其他3种植物反应相反,这可能与荒漠草本植物种不同生长特性有关。  相似文献   

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Response of reindeer and caribou to human activities   总被引:4,自引:0,他引:4  
Petroleum and mineral exploration and extraction, hydroelectric development, atmospheric transport of contaminants, timber harvesting and tourism are increasing worldwide, especially in the Arctic. This development may adversely affect populations of reindeer/caribou ( Rangifer tarandus ) which are the basis of subsistence economies for northern indigenous peoples. Our purpose is to present a survey of the literature that has investigated the response of reindeer/caribou to human activities. Individuals and groups of reindeer/caribou: 1) move away from point sources of disturbance; 2) increase activity and energy expenditure near disturbance; 3) delay crossing or fail to cross linear structures; 4) shift away from areas of extensive and intensive development; and 5) are killed by collisions with vehicles and by hunting along roads. Cows and calves during the calving season are the most easily disturbed group. Bulls in general and all reindeer/caribou during insect harassment are least likely to avoid development areas. Estimation of the proportion of a population that is exposed to disturbance and the implications of this exposure to annual energy budgets, survival and productivity of reindeer/caribou has received little attention. Future advances in understanding the implications of human disturbance to reindeer/caribou will require cumulative effects assessment at annual, population and regional scales. Although some level of cumulative effect is likely, clear separation of cumulative effects of development from natural variation in caribou habitat use and demography will be difficult.  相似文献   

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Valid Games? A Response to Erica Schoenberger   总被引:4,自引:4,他引:0  
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杨林  董玉祥  黄德全 《热带地理》2021,41(5):968-974
采用RTK GPS测量技术与方法,在2014—2017年对福建平潭岛典型海岸沙席进行了连续16次形态高精度测量,分析了海岸沙席在台风作用下的形态变化及台风季后的形态恢复变化特征.结果表明:1)海岸沙席对台风的形态响应特征明显,基本表现为海滩及沙席前缘高度降低(最大侵蚀深度为0.92 m),沙席中部高度变化相对较小(≤0...  相似文献   

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To evaluate and provide an appropriate theoretical direction for research into climate-vegetation interactions using meteorological station data at different time scales, we examined differences between the Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) and their responses to climate factors. We looked for correlations between data extracted from MOD13Q1 remote sensing images and meteorological station data for the two indexes. The results showed that even though NDVI and EVI are derived from the same remote sensing image, their response to climate factors was significantly different. In the same meteorological station, the correlation coefficients for NDVI, EVI and climate factors were different; correlation coefficients between NDVI, EVI and climate factors varied with meteorological station. In addition, there was a lag effect for responses of NDVI to average minimum temperature, average temperature, average vapor pressure, minimum relative humidity, extreme wind speed, maximum wind speed, average wind speed and average station air-pressure. EVI had a lag only for average minimum temperature, average vapor pressure, extreme wind speed, maximum wind speed and average station air-pressure. The lag period was variable, but most were in the -3 period. Different vegetation types had different sensitivities to climate. The correlation between meteorological stations and vegetation requires more attention in future research.  相似文献   

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在全球气候变化背景下,各地极端气候事件有上升趋势。其中以洪涝和干旱灾害对人类生活的影响最大、最频繁。在长期应对干旱灾害的经历中,北美洲各国逐渐形成了较为完善的干旱灾害应对模式,通过立法、风险管理、制定干旱计划、工程措施与非工程措施相结合等多种手段降低干旱灾害带来的损失。通过文献查阅与综述方法,结合北美洲国家相关网站介绍...  相似文献   

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遵义红色旅游网络关注度的客流响应研究   总被引:1,自引:0,他引:1  
采用2010年国内各省区关于遵义红色旅游的逐日关注度及遵义核心景区逐日客流数据作为研究样本,从空间视角对旅游网络关注度与客流展开探讨,研究发现遵义红色旅游的网络关注度及客流量在区域空间上具有明显的呼应关系,两者均存在距离衰减特征;同时经一元相关分析得出关注度与客流的相关系数为0.757022,表明两者在距离上递减的协调同步性,也由此证明旅游客流对网络关注度具有较高的响应度.其次,遵义红色旅游网络关注度及客流与经济收入水平相关系数小,表明两者的分布状况与国内收入水平差异存在较小关联,但两者之间在经济水平梯度上却体现了一定程度的对应关系.  相似文献   

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