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41.
北京南海子麋鹿苑鸟类多样性研究   总被引:1,自引:0,他引:1  
城市公园及城市其他自然保护地是城市生态系统的重要组成部分,是城市鸟类最主要的栖息场所。城市化进程对城市的自然景观和生态系统造成很大影响,鸟类生存空间不断缩小,其群落结构受到影响。南海子麋鹿苑周边正在经历快速城市化,为了摸清该地区鸟类群落组成及多样性,自2014年10月起对研究区野生鸟类种类、数量和分布特点进行连续调查,共记录鸟类18目、49科、156种;其中,国家II级重点保护鸟类16种。鸟类优势种随年份变化和季节变化不一,总体来看,绿头鸭、灰喜鹊、喜鹊、[树]麻雀等留鸟为研究区优势种。研究区鸟类Shannon多样性指数和Pielou均匀性指数呈现2018年>2017年>2016年>2015年的变化规律;鸟类Shannon多样性指数和Pielou均匀性指数呈现秋季>夏季>春季>冬季的变化规律。同时,探讨了影响鸟类多样性的因素,提出连通城市绿地,打通动物迁徙通道;坚持山水林田湖草理念,创造多样的景观;对野生动物重点保护区域限制人类活动,保护野生鸟类生境等建议。  相似文献   
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Vitality is a genetic preservation factor that keeps a tree in the right condition. Changes in tree vitality are a measure of the impact exerted on trees by environmental factors, such as injuries to trunks and branches, and are among the basic parameters of the state of their preservation. The dynamics of changes in the width of annual increments of trees is one of several parameters characterizing the level of their vitality. The aim of the study is to determine changes in radial increment and linking them to the level of the vitality of Scots pines (Pinus sylvestris L.) and European beeches (Fagus sylvatica L.), on which the standard (old system) and specially designed (new system) systems of fastening of wooden platforms were installed as part of adventure park infrastructure. In the old system, the platforms were installed on square wooden beams placed in milled tree trunks, while in the new system on semi-circular metal brackets matching the curvature of the trunks. The present research is aimed to determine the dynamics of incremental trends in trees with different platform systems in relation to the reference group, and to determine the impact of the tested support systems on trees with different levels of vitality. Most of the studied trees were in the optimum stage of increment. The initial tree vitality level recorded at the beginning of the experiment was clearly better for the beech stands. In the case of Scots pine, the average vitality was close to stable. Pines that were initially in better condition responded much worse to the installation of old system platforms compared to those with the specially new platform system. A similar trend was also visible in the case of beeches, but the differences were not that clear and the annual increments of the trees with platforms installed were slightly higher compared to the reference trees. The trees that were initially in worse condition, both pines and beeches on which the old system of platforms had been installed, responded by increasing the width of annual increments during the measurement period. The described response of trees most probably does not result from the lower harmfulness of the old support system, but from the defensive responses of trees subjected to stronger stress.  相似文献   
44.
中国生态工业园区发展现状与展望   总被引:8,自引:0,他引:8  
田金平  刘巍  臧娜  陈吕军 《生态学报》2016,36(22):7323-7334
综述了中国生态工业园区的发展,主要内容包括:(1)中国工业园区的发展历程和面临的挑战;(2)中国生态工业园区的发展历程与发展模式;(3)3个角度分析中国生态工业园区建设取得的环境绩效,即基于生态工业示范园区验收及规划基准年绩效变化,基于数据包络分析法的生态工业示范园区环境绩效和基于环境绩效指数方法的生态工业园区环境绩效评价;(4)国内外关于生态工业园区的研究现状和热点;(5)中国生态工业园区发展和研究面临的难点及未来发展展望。面向中国工业园区绿色低碳循环发展需求,以期通过对生态工业园区发展的回顾和评述,为园区实践者和决策者及后续研究提供参考。  相似文献   
45.
庄思冰  龚建周  陈康林  李江涛 《生态学报》2023,43(14):5714-5725
小型公园绿地是城市生态系统文化服务的重要载体,自新冠疫情爆发以来,这类型公园绿地更是成为提供重要文化服务的场所。以粤港澳大湾区为研究区域,从潜在供给和潜在需求两个方面量化小型公园绿地文化服务,利用空间自相关与耦合协调度模型,探讨粤港澳大湾区文化服务供需的空间分布及匹配特征。结果如下:(1)生态系统文化服务供给具有明显的梯度分布,大致呈现中间低、四周高的特点;文化服务需求在城市中心区域呈连片分布。(2)文化服务供给在城市之间连片、以高-高聚集区域为主,需求则以低-低聚集为主、连片集中于城市中心,供需双变量则以高供给-低需求的聚集态为主、集中于研究区四周。(3)52.2%的区域属于文化服务需求不足,5.2%的区域供给不足。从小型公园绿地文化服务来看,粤港澳大湾区存在一定比例的生态系统文化服务供需错配现象,为提升人类在抵御重大突发事件过程中的生活质量,可分区管理自然生态系统。  相似文献   
46.
产业园区温室气体排放清单   总被引:3,自引:0,他引:3  
齐静  陈彬 《生态学报》2015,35(8):2750-2760
温室气体排放所导致的全球气候变化是国际社会长期关注的热点问题,它严重限制了人类社会的发展并威胁着人类的生存。产业园区通常集中了一个区域主要的生产要素与生产能力,也代表着特定产业在该区域的发展水平,理应作为发展低碳经济的基础单元和减少温室气体排放的重要控制点,也可以成为解决区域资源、环境问题的突破口。明确了产业园区温室气体排放的系统边界和内部结构,梳理了产业园区全生命周期温室气体排放行为,综合考虑产业园区能源消耗、工业生产、物质材料消耗、仪器设备投入、废弃物处理处置、景观绿化等过程,建立产业园区温室气体排放核算方法,并对案例园区进行了清单分析。结果表明:案例园区整个生命周期的温室气体排放量为1872177 t CO2-eq,其中运行管理阶段占全生命周期排放的比例最高,为95.35%。建设阶段的温室气体排放总量中建筑材料消耗引起的排放占到96.95%,主要集中在建筑工程、内部装修工程和外部装饰工程3个环节。运行管理阶段电力消耗、热力消耗和污水处理过程的排放量占到总量的98.69%。根据核算及分析结果提出了案例园区在建设和运行管理阶段实现温室气体减排的建议。  相似文献   
47.
Techniques for analyzing hormone metabolites in animal excreta have created many opportunities for noninvasive monitoring of health, reproduction, and welfare in zoo animals, but can be difficult to implement when individual samples are not readily identifiable in animal groups. A common approach to this problem is to feed animals an indigestible marker that subsequently appears in feces, but there has been little systematic research on the use of such “fecal markers.” First, we used an online survey to assess the prevalence of fecal marker use in North American zoological institutions. Second, we conducted a series of experimental tests utilizing commonly employed fecal markers in a variety of typical zoo taxa to determine the: (1) effectiveness of several markers to accurately distinguish samples in a variety of species, (2) minimum quantity of marker needed for detection, and (3) length of time between ingestion and detection in the feces. The majority of the 45 institutions that completed the survey reported using fecal markers with their collections. The survey also revealed that the most frequently used markers are seeds/grains and food colorants, with the former generally used in Carnivora and the latter in Primates. Our experimental data confirmed the success of these taxa/marker combinations and also revealed that food colorants function as markers in a variety of avian, reptilian, and mammalian species. Our data describe successful fecal markers for a wide variety of zoo taxa and should, therefore, be useful for zoological managers and researchers needing to employ fecal markers in future investigations. Zoo Biol 30:379–398, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
48.
The purpose of this paper is to present strategies for teaching animal behavior within a mixed traditional and nontraditional format. Based on our experience, it is very useful to use zoological parks as convenient locales for observational studies. Students gain many valuable experiences in a nontraditional course such as this. Various suggestions are made for animal behavior courses and student projects. Some of the potential pitfalls and problems associated with an animal behavior course are also discussed. Finally, future directions are suggested.  相似文献   
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This paper summarizes the historical development of nature conservation programs, and discusses the past and current case of national parks in Turkey. The study evaluates biodiversity inventory data, international and national importance of biodiversity, environmental problems threatening natural resources, historical developments in nature conservation, institutional development for conservation programs, participation of Turkey in international agreements, and national conferences and meetings to advocate nature conservation. Finally, the developments and current conditions of conservation programs and national parks are also discussed.  相似文献   
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