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1.
Movements and corridors of African elephants in relation to protected areas   总被引:1,自引:0,他引:1  
Understanding how mammals satisfy their need for space in fragmenting ecosystems is crucial for ecosystem conservation. Using state-of-the-art global positioning system (GPS) technology we tracked 11 focal African elephants (Loxodonta africana) in Kenya at 3-hourly fix intervals and collected between 34 and 406 days per individual. Our recordings gave a high spatio-temporal resolution compared to previous studies and allowed novel insights into range use. The actual ranges of the tracked elephants are smaller than usually represented. Moreover, the ranges in our sample were complex and not confined to officially designated protected areas, except where fenced. All the unfenced elephants in our sample had distinct home sectors linked by travel corridors. Within each home sector the elephants concentrated in favourite core zones. Such core zones tended to lie in protected areas whereas corridors typically crossed unprotected range. Elephants moved significantly faster along corridors than elsewhere in their range, which suggests awareness of danger outside the protected area. We conclude that understanding the complex use of an animals range is crucial for conservation planning aiming to balance animal interests with those of human beings that co-habit in their range.The revised version was published online in April 2005 with correction to figure 1a and b.  相似文献   

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随着对排污许可固定污染源全覆盖的理解逐步深化,排污许可在实践中不断深入推进。一是突破"片面覆盖",不再仅仅服务于总量控制和仅适用于部分地区;二是关注点从"排放"转移到"控制",实现污染物"全覆盖",从水、大气扩展到其他污染物;三是关注点从"许可"到"许可制",名录增加了登记管理类别,实现排污单位"全覆盖";四是关注点从"发证"到"监管",实现排污许可要求从纸面到实际的"全覆盖"。  相似文献   

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旅游还是游憩?我国国家公园的公众利用表述方式反思   总被引:1,自引:0,他引:1  
自国家公园试点工作推行以来,有关国家公园到底能不能开展旅游活动以及开展什么样的旅游活动,到底是旅游活动还是游憩活动的争议从未停止。在分析“旅游”和“游憩”内涵的基础上,结合国外在国家公园利用方式的相应表述,根据我国建设国家公园的基本国情,对我国国家公园建设中的“游憩”与“旅游”问题进行了讨论。结论认为:国家公园内的“游憩”与“旅游”实际上是一体两面,在公园的功能定位与分区规划中,使用“游憩”一词比较合适,以体现国家公园的公益性目标。但在国家公园的具体运营管理中,使用“生态旅游”一词进行表述更恰当。在谈及旅游与国家公园的矛盾时,使用“旅游开发”更符合事实。  相似文献   

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21世纪经济与环境协调发展全新思维模式的建立   总被引:8,自引:2,他引:6  
学习科学发展观,很重要的内容是改变人们传统的思维方式.传统的经济发展模式决定了传统的思维模式,21世纪的经济发展突飞猛进,科学发展观要求建立新的思维模式.介绍了4种思维方式:从"信息公开"与"人权"的概念出发,树立"规制"的思维模式,全方位变革人们的工作方法;从先进文化的高度,进行"绿色"思维,把经济发展推进到一个新的层次;从哲学角度,超越原有的规范,建立在竞争基础上不断合作的"整合"思维模式;从"以人为本"的理念出发,进行"协同"思维,深层次解决经济与环境的发展问题.   相似文献   

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《Die Naturwissenschaften》1989,76(10):488-488

Naturwissenschaften Aktuell

Bei Gebildeten ist die Ablehnung der Gentechnik besonders ausgeprägt  相似文献   

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指明了“洁净技术”的合理含义 ,阐述了英国“洁净技术”的内容和政府主要部的研究项目 ,介绍了近年来英国新的重点研究领域与政府支持“洁净技术”的政策措施 ,讨论了英国“洁净技术”政策的意义 ,及其对我国“洁净技术”开发和应用的启示  相似文献   

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宋国君 《上海环境科学》2001,20(12):574-576
以固定点源烟尘排放为例,从排放标准和监测标准两方面讨论了中国现阶段“达标排放”的状况,指出当前的大气污染源达标排放实际上是“初步达标排放”,现在的排放标准和监测规范合适考核污染源的初步达标排放,不适合考核污染源的连续达标排放。排放标准的规定形式、监测规范和适用范围需要改革。现在的排放标准指标需要与监测规范和超标率限值结合起来,以促进污染源的连续达标排放。  相似文献   

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本文根据资源的“绝对”不可再生、相对不可再生、相对可再生和“绝对可再生”的各自特性,论述了资源物质变换在可持续发展中的重要地位。  相似文献   

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本文认为"两课"教学方面既存在"假缺乏"实效性的误解,更存在"真缺乏"实效性的现实."假缺乏"实效性的原因是评价标准错位,"真缺乏"实效性的根本原因是授课教师授课时不能有效解决"为什么"有何用"层次的问题,在分析原因的基础上,提出了进一步增强"两课"教学实效性的具体措施.  相似文献   

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Animals respond to signals and cues in their environment. The difference between a signal (e.g. a pheromone) and a cue (e.g. a waste product) is that the information content of a signal is subject to natural selection, whereas that of a cue is not. The model free-living nematode Caenorhabditis elegans forms an alternative developmental morph (the dauer larva) in response to a so-called dauer pheromone, produced by all worms. We suggest that the production of dauer pheromone has no fitness advantage for an individual worm and therefore we propose that dauer pheromone is not a signal, but a cue. Thus, it should not be called a pheromone.  相似文献   

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污染转移分析及对策   总被引:8,自引:0,他引:8  
“污染转移”已经成为发达国家处理各种有害废物的重要途径并严重阻碍了输入国的经济发展。自改革开放以来,特别是加入WTO以后,由于国际贸易的迅猛发展,我国已经被一些发达国家视为新的污染物交易对象国,各种有毒有害废物交易日益增长,占国际贸易额的比重也越来越大。本文首先分析了我国目前存在的“污染转移”的现状,接着驳斥了发达国家所鼓吹的“污染转移”有利于进口国的理论依据——“经济理性论”和合理旗号——“比较优势说”,最后提出了我国限制“污染转移”的对策措施。  相似文献   

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In species with more than one male reproductive morph, there typically exists a larger morph with exaggerated secondary sexual characters, and a smaller morph with reduced secondary sexual characters. These exaggerated and reduced morphologies are commonly thought to represent specializations to alternative behavioral reproductive tactics—large body size and exaggerated secondary sexual characters should both facilitate territoriality, courtship, and pair-spawning; while small body size and reduced secondary sexual characters should facilitate sneaky cuckoldry. Given this postulated relationship between morphology and behavior, we examined the relationship between the morphology of exaggerated males and cuckoldry. In a field and aquarium study of the midshipman fish, a fish with both exaggerated and reduced morphs, we demonstrated cuckoldry in some males of the exaggerated morph. Since the reduced morphology is thought to be an adaptation towards sneaky cuckoldry, we predicted that, of males with the exaggerated morph, less-exaggerated (smaller) males would be better able to gain proximity to the spawning pair during cuckoldry. In contrast to that prediction, access to the spawning pair during cuckoldry increased with the body size of the cuckolding exaggerated-morph males. This may be related to our observation that exaggerated males often cuckolded aggressively. Thus the exaggerated morphology need not preclude adaptive plasticity to cuckoldry, and may even aid it.  相似文献   

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针对航空装备环境鉴定试验大纲审查中暴露的研制总要求或成品技术协议书中对"使用环境"、"环境要求"表述方面的问题,阐述了环境适应性要求的内涵和合理的表征方法,分析了目前型号中"使用环境"和"环境要求"等概念的不完整性及其带来的一些副作用,提出了使用方和型号总师单位应尽快理解和掌握有关标准中环境适应性要求的正确表述方式,并将其纳入相关文件的建议。  相似文献   

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