首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
湖滨带湿地截磷研究进展及问题探讨   总被引:1,自引:0,他引:1  
湖滨带湿地是面源污染汇入湖泊的过渡区域,也是湖泊天然的保护屏障。磷素是面源污染的主要组成,同时也是水体中最难被去除的污染物之一,其过量输入是造成湖泊富营养化的重要原因。湖滨带湿地的截磷作用能大大削减进入湖泊的外源磷负荷,研究湖滨带湿地的截磷机制对于水污染防治和湖泊生态系统保护具有显著意义。简述了湖滨带湿地截磷研究进展,并分析了目前研究中的关键问题。采用宏观分析与微观机理研究相结合的方法,发展宏观大尺度分析、微观协同作用与模型研究,强化湖滨带湿地的截磷效率,提升湖滨带湿地的整体生态功能,是解决湖泊富营养化问题的关键。  相似文献   

2.
采用样带法研究了巢湖东部水源区湖滨带植物群落的分布规律,从而探索受损湖滨带植被的修复途径。研究表明:巢湖东部水源区湖滨带共有植物47种,隶属于23科、40属。TWINSPAN分类把45个样方划分为12个群丛,结合各样方实际水面以上高程,将其归并为5个群落类型。DCA排序结果表明水分和土壤基质类型是决定湖滨带植物群落分布的主导因子。结合巢湖多年水文数据分析了湖滨带优势物种与水文的关系,并建议竹叶眼子菜作为沉水植物恢复的先锋物种,荇菜作为浮叶植物恢复的先锋物种,苔草、芦苇等植物作为近岸区域恢复的主要物种  相似文献   

3.
首先概述了巢湖湖滨带及滨湖区生态系统现状,包括土地利用、理化环境、水生植物及底栖动物群落结构,然后对整合湖滨带生态修复技术体系,提出了环湖岸线和水向湖滨带修复方案。前者运用混凝土 原位土壤 植被混合护坡系列技术建立稳固的环湖生态岸线,后者运用水位调控技术和基底改善技术恢复湖滨带水生植被  相似文献   

4.
高原湿地剑湖湖滨带功能作用的定量研究   总被引:1,自引:0,他引:1  
采用野外采样与室内分析的方法,从水质和底泥两个方面定量研究剑湖湖滨带的功能作用。结果表明,湖滨带在水质净化和拦截泥沙等方面效果显著,特别是对水中总氮与总磷的平均去除率分别高达66.28%和45.73%,其拦截作用表现为:迎水面的泥层厚度是背水面的1.5倍;底泥的各项指标(除pH值),湖滨带背水面均比迎水面高,速效磷和全氮的增加量最为明显,其含量分别是迎水面的3.30和2.61倍,这主要与湖滨植物带大量吸收入湖矿质营养用于自身生长,其残体在背水面沉积有关,从另一角度体现了湖滨带的吸附、净化功能。因此,要重视并保护湖滨带,从而使其功能得到有效发挥。  相似文献   

5.
洪湖湖滨带植被现状以及近五十年的变化分析   总被引:1,自引:0,他引:1  
洪湖湖滨带是洪湖湿地的重要组成部分,具有涵养水源、保持水土、截污缓冲、维持生物多样性的功能。为了解洪湖湖滨带植被现状及变化过程,进行了洪湖湖滨带植被调查,结合土地利用实地勘察和卫片分析,结果显示空心莲子草、马唐、狗尾草、葎草、小飞蓬、菰、莲、芦苇、凤眼莲和浮萍综合优势比高,是洪湖湖滨带优势种。物种数较20世纪60年代明显减少。其中入侵种空心莲子草和凤眼莲在各样地出现的频率很高。以全部植物种计算,湖滨带植被Shannon-Weaver指数在1.50~2.98之间,Simpson指数在0.7~0.9之间,但以水生植物种计算,多样性明显降低,其Shannon-Weaver指数处在0.69~2.29之间,大多数均小于2,Simpson指数在0.50~0.89范围变动。根据卫片分析,2011年湖滨带水位变幅区面积为62.72km2,与60年代相比缩减71.4%,实地勘察证实洪湖原有湖滨带大部分已被开发成鱼塘和居住地。综合调查结果和历时资料表明,洪湖湖滨带植物种类减少,多样性降低,生态功能显著降低。  相似文献   

6.
巢湖水向湖滨带底栖动物群落结构研究   总被引:1,自引:0,他引:1  
2009年6月和11月对巢湖水向湖滨带底栖动物进行群落结构调查。共采集到底栖动物33种,隶属9科29属,以寡毛类和水生昆虫为主,合计占总种类数的79%。底栖动物的平均密度和生物量分别是506 ind./m2和11534 g/m2。巢湖水向湖滨带底栖动物群落结构趋于单一化,敏感种(光滑狭口螺、长角涵螺等)减少或消失,而耐污种(苏氏尾鳃蚓、霍甫水丝蚓、环棱螺、淡水壳菜等)成为优势种。水向湖滨带底质是影响底栖动物分布及现存量的主要因素,堤岸间接影响其组成和分布,淤泥底质中底栖动物密度最高,砾石底质中生物量最高,而较硬的粘土底质中现存量最低。在功能摄食类群方面,巢湖水向湖滨带以直接收集者和过滤收集者为主。依据本研究结果,对巢湖水向湖滨带生态修复提出了建议  相似文献   

7.
针对巢湖湖滨带水生植物消失的问题,提出浅水区自组织生态修复技术框架,并开展工程示范。该技术框架依据湖泊水生植被恢复的环境条件需求,针对不同区域湖滨带情况,提出合理的修复目标,进而集成系列工程措施,改善湖滨带环境并恢复水生植被。根据该技术框架实施中试工程,恢复湖滨带水生植被面积5万m2,使水生植物多样性增加70%,植被盖度由30%提高到60%。该技术为巢湖湖滨带生态修复提供技术支撑,有较强的实际应用价值  相似文献   

8.
南四湖新薛河湖滨带湿地修复效果评价   总被引:1,自引:0,他引:1  
通过对南水北调东线南四湖新薛河入湖口湖滨带人工湿地修复区的植物群落组成和物种多样性进行调查,采用Shannon-Wiener指数、Simpson指数、均匀度指数和丰富度指数对该地区的植物物种多样性进行分析,以评价退耕还湿措施对湖滨带退化湿地的生态修复效果.结果表明,经过2年的生态修复工作,湖滨带退化湿地中的植物物种数量由修复前的16科25种提高到修复后的24科47种.修复后的湖滨带湿地生态系统具有较高的生物多样性,其物种多样性明显高于未修复地区,其中,修复后的湿地高位台田区Shannon-Wiener指数、Simpson指数、均匀度指数分别为1.619、0.745和0.860,远高于未修复高位台田区的0.060、0.012和0.065.通过退耕还湿措施修复的湖滨带人工湿地系统对于恢复南四湖湿地的物种多样性、实现湖滨带湿地生态系统的自然可持续性具有重要的意义.  相似文献   

9.
巢湖藻华易堆积区蓝藻时空分布的研究   总被引:1,自引:0,他引:1  
巢湖西半湖采样分析结果表明夏季蓝藻水华主要集聚于湖滨带。因此选择西半湖藻华易堆积的区域,并监测在风力驱使下蓝藻水华的时空分布规律,分析湖滨带浮游植物生物量与理化因子的相关性。结果表明:湖滨带水华生物量的分布容易受到风向和天气的影响;水体的叶绿素a浓度与总氮(TN)、总磷(TP)和高锰酸钾指数(CODMn)呈显著的正相关(p<001);湖滨带水体中微囊藻(Microcystis)的生物量几乎占据水体总浮游植物生物量的95%以上,而且越靠近湖岸带微囊藻的生物量所占的比例越大。据此,可以选择湖滨带水华易聚集区作为蓝藻水华尤其是微囊藻去除的重点区域,以有效地削减蓝藻水华污染,从而为巢湖水生态系统的修复创造条件  相似文献   

10.
以植被生物完整性评价梁子湖湖滨湿地生态系统健康   总被引:5,自引:0,他引:5  
湖滨湿地植被是湖滨带生态系统的主要特征,以湖滨湿地植被为对象可评价湖滨带生态系统健康状况。通过对梁子湖湖滨湿地植被的详细调查,共鉴定出植物182种,隶属于52科128属,其中湿生植物147种,水生植物35种。水生植物中有20种挺水植物,6种浮叶植物和9种沉水植物。采用植被生物完整性(VIBI)方法评价梁子湖湖滨湿地生态系统健康,对21个备选指标进行筛选分析,建立了以挺水植物物种数、多年生植物物种数、外来物种百分比、香农多样性指数、植物区系质量指数FQAI、耐受性物种百分比、敏感性物种百分比为核心指标的评价体系,三分法对指标进行赋值,将梁子湖湖滨湿地划分为健康、良好、一般和较差4个等级。评价结果表明,梁子湖湖滨湿地22个调查位点中,处于健康状态的有3个位点,良好6个,共占总位点数的41%,一般和较差分别为7个和6个,共占59%。总体上看,东梁子湖和牛山湖湖滨湿地位点健康状况较好,而西梁子湖湖滨湿地差异性较大,山坡湖南部湖湾和前江大湖北部位点健康状况良好,张桥湖湖滨湿地健康状况一般,评价较差的6个位点集中在宁港湖周围和前江大湖南部沿岸。底质和人类活动如水位调控、围网养殖、放牧等是影响梁子湖湖滨湿地植被生物完整性的主要原因。  相似文献   

11.
The spatial and ethological structure of populations and territorial behavior of Sylvia warblers have been studied at the northern periphery of their nesting ranges (southern Karelia). It has been found that under these conditions the warblers form sparse populations, with individual pairs occupying large territories, and their behavior is characterized by minimization of territorial expenditures (relatively brief vocalization and the absence of aggressive interactions).  相似文献   

12.
Despite overwhelming scientific consensus, millions of Americans fail to view climate change as a pressing threat. How can we address this disconnect between science and public opinion? In the present study, we investigated the role of metaphorical framing in shaping attitudes toward climate change. Participants read a brief article that metaphorically described US efforts to reduce carbon emissions as a war or race against climate change, or non-metaphorically described it as the issue of climate change. We further manipulated whether these emission-reduction goals emphasized the relatively near or distant future. We found that, compared to the race frame, the war metaphor made people perceive more urgency and risk surrounding climate change and express a greater willingness to increase conservation behavior, irrespective of the time horizon. Those who read the non-metaphorical report tended to respond in between these two extremes. We discuss the implications of these findings for climate communications.  相似文献   

13.
This essay introduces and illustrates tensions of praxis that humans involved in activism face so that thought–action translation can occur more reflexively. Because social movements face unique challenges in effecting social change (Simons, 1970; Stewart, Smith, & Denton, 2007) the tensions of praxis are especially important for this type of social change agency. Therefore, this essay situates itself within discussions of environmental social movements and begins with a brief introduction of praxis as a theoretical and practical concern. Then, in order to illuminate the tensions of praxis, the following tensions are identified, explained, and illustrated: (1) this world or that world; (2) activity or inactivity; and (3) means and ends. Throughout the essay, primary data from a 2009 interview with Julia Butterfly Hill are used to illustrate these tensions. The essay concludes with theoretical and practical significance of the tensions of praxis and suggests directions for future research.  相似文献   

14.
本文论述了中国水利水电工程开发与区域可持续发展的关系,并提出了中国实现可持续的水利水电工程开发的主要对策。  相似文献   

15.
China’s climate change policy has rapidly evolved from one of neglect to necessity with sinologists drawing on a wide range of theories in trying to explain this shift. The rising influence of citizens' movements coupled with international pressure are often cited as significant drivers behind the government’s evolving climate change strategy. But can the influence of public pressure and international lobbying offer a complete explanation for the government’s dramatic policy changes? In this article, we advance theoretical pluralism where three contending schools of thought are made complementary to offer distinct explanations for understanding the mechanisms and rationale for Beijing’s elite-driven climate change policy. In brief, by bridging three separate theoretical streams including rational choice theory, authoritarian environmentalism and advocacy coalition framework, we show that the interests of elites in China’s upper political echelon are the driving force behind the country’s climate change policy.  相似文献   

16.
The 2007 Recommendations of the International Commission on Radiological Protection (ICRP) represent a change from a process-based to an exposure-based approach, where exposure situations are categorised as planned, emergency, and existing exposure situations. Although the new Recommendations contain further changes based on, inter alia, scientific developments since the publication of the 1990 Recommendations, they overall represent more continuity than change – a notable exception being the direct consideration of environmental protection. The implications of the new Recommendations for radioactive waste management are fairly marginal, as earlier recommendations in this area are still considered valid. This communication provides a brief overview of the current ICRP system for radiological protection as applied to radioactive waste management, as well as an outlook including the possibility of using the developing ICRP system for management of environmental effects as an ‘alternative way of reasoning’ when building the safety case for a specific waste disposal concept.  相似文献   

17.
成都平原城市群的城市流分析   总被引:2,自引:0,他引:2  
在西部大开发战略不断深入的宏观背景下,以西部地区代表性的城市群--成都平原城市群为例,运用城市流的方法分析城市群内5个主要城市间的空间相互作用,计算并找出不同城市的基础部门和城市流强度,得出结论:成都平原城市群内城市之间外向服务功能呈现明显的差异,有着较好的错位发展空间;在具体产业表现上,交通运输仓储和邮电通信业发展良好,而房地产业、文化体育和娱乐业和公共管理社会组织发展不均衡;成都的城市流倾向度值表明了其当之无愧地成为成都平原城市群的中心城市;次位城市绵阳面临自身内向性发展不足的问题;城市群内部城市的等级分化明显,城市化水平存在巨大的差距。并提出加强成都平原城市群内部联系的简要建议和未来研究的展望.  相似文献   

18.
A major diesel emissions research program has been initiated by the U.S. Environmental Protection Agency to assess the human health risk associated with increased use of diesel automobiles. This program is intended to establish the mutagenic and carcinogenic potency of complex organics associated with diesel particles as well as comparative particle-bound organics from other environmental emissions for which human epidemiological data are available. The mobile source samples selected for this study were collected from a heavy-duty diesel engine, a series of light-duty diesel passenger cars, and a gasoline catalyst automobile. The comparative source samples incorporated into the study were cigarette smoke condensate, coke oven emissions, roofing tar emissions, and benzo(a)pyrene. The samples were tested using three mutagenic assays and four carcinogenic assays as prescribed by a test matrix. This report describes the study design, particle generation, and sample collection and preparation. A brief summary of the bioassays is also included.  相似文献   

19.
环境CGE模型的发展及特征分析   总被引:6,自引:1,他引:6  
随着CGE模型在环境与经济政策分析领域中的应用不断拓展 ,环境CGE模型的研究和应用也逐渐走向深入。本文在简要介绍CGE模型的发展状况和主要特征之基础上 ,对环境CGE模型的发展、类别、特征及其局限性进行了较为详细的分析  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号