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1.
病毒是地球上丰度最高的生命形式,广泛分布于包括深部生物圈在内的各种环境中。病毒通过侵染微生物宿主影响其生理特征、生态过程和生物地球化学循环。研究发现,病毒裂解是导致深海底栖原核生物死亡的主要原因,这一认识引起了研究者对底栖病毒的广泛关注。为了更为全面地认识底栖病毒的生态作用,本文分析了底栖病毒的生态特性(分布、丰度、多样性和生活方式),动力学过程与影响因素,与宿主的相互作用以及在碳循环上的生态贡献。同时,对底栖病毒未来在生物学、生态学和生物地球化学领域的研究方向提出了展望,论文旨在提升对底栖病毒生态作用的理解,为底栖病毒生态学和相关学科的发展提供借鉴。  相似文献   

2.
IntroductionWetlandisoneoftherichestbiodiversityareasintheearth .Biodiversityshouldincludefourlevels:hereditydiversity ,speciesdiversity ,ecosystemdiversityandlandscapediversity .Speakingfromcertainangles,theprotectionofecosystemdiversityandlandscapediver…  相似文献   

3.
Wetland is one of the richest biodiversity areas in the earth. The main purpose of establishing wetland protected area is to protect biodiversity, and the protection of ecosystem diversity and landscape diversity is the key to protect biodiversity. In order to protect regional ecosystem and landscape, it is a good way to establish wetland comprehensive protected area which connected wetland nature reserves by habitat corridors. The Sanjiang Plain as a study area, its landscape evaluation index system on wetland protected area was studied, and some problems on landscape planning and ecology construction were further approached in this paper. It showed that establishing wetland comprehensive protected area is very important to protect regional wetlands, to maintain ecological balance,and to improve the sustainable development of agriculture and industry in this region.  相似文献   

4.
喀斯特生态系统是陆地生态系统的重要组成部分,生态恢复是喀斯特石漠化治理的核心任务,研究石漠化生态恢复机理、优化生态系统功能、提升生态系统服务和实现喀斯特生态环境可持续发展是当前石漠化治理的重要议题。通过对遗传、物种、生态系统和景观四个层次生物多样性退化与恢复的关注,生物多样性作为重要的生态系统特征及表征指标,在石漠化生态恢复研究中已取得一定进展,主要集中于石漠化生态恢复中土壤微生物遗传多样性特征及利用潜力、适生物种的筛选及生态恢复功能、不同生态系统中生物群落特征及生态系统恢复、石漠化景观格局的时空演变及优化对策等方面。但是相关研究侧重于物种多样性而对于功能多样性的探讨较为欠缺,物种间以及多营养级生物多样性效应研究仍较薄弱,生物多样性与生态系统功能、生物多样性与生态系统服务之间的协同恢复机制缺乏深入研究。今后,应针对喀斯特石漠化生态恢复中的植物群落构建,多营养级生物多样性纳入生态恢复,生物多样性增强生态系统功能、生物多样性提升生态系统服务等方面加强研究。  相似文献   

5.
青藏铁路格望段工程生态影响的主要特征:线型切割   总被引:2,自引:0,他引:2  
线型工程是主要的生态类项目之一,随着各类线型工程迅速增加,其引发的生态影响已经逐渐暴露出来。本文分析了线型切割影响的提出背景以及景观生态学在研究线型工程生态影响中的应用。并以青藏铁路格望段为例,分析了线型切割作用的具体表现,主要包括:阻断能流、物流、物种流;阻断生态用水;阻断野生动物迁徙通道;造成景观破碎化。同时,针对不同的切割影响提出了相应防护对策,包括修建排水建筑物、生物通道、树篙廊道等。  相似文献   

6.
Wulingyuan is located at the mountainous area of the middle reach of the Yangtze River,it is one of the three nature heritages in China which ranks in the “List of Worls‘s Heritage”by UNESCO.It is characterized by quartz sandstone peaks landform with several landform components(pattern,corridor)and rich in landscape ecological diversity and biodiversity.The main patterns(ecosystem)include mid-height mountain peaks,rift-avlley and streams among peaks,peaks and gullies on slopes,square mountain-platforms and peaks among blind valleys and so on.The corridor system consists of natural corridors and artificial corridors among which the stream corridors account for a major part.The fracturing of habitat is unfavorable for the biodiversity conservation,but meanwhile the habitat diversity leads to an increase in biodiversity.Therefore,it is still rich in landscape ecological diversity in Wulingyuan.The biodiversity at the level of landscape component(ecosystem) and the function of the Wulingyuan complex ecosystem,and the measures for the biodiversity conservation in Wulingyuan ecotourism area are discussed in this paper.  相似文献   

7.
We critically highlight some evidence for the importance of soil biodiversity to sustaining (agro-)ecosystem functioning and explore directions for future research. We first deal with resistance and resilience against abiotic disturbance and stress. There is evidence that soil biodiversity does confer stability to stress and disturbance, but the mechanism is not yet fully understood. It appears to depend on the kind of stress and disturbance and on the combination of stress and disturbance effects. Alternatively, community structure may play a role. Both possible explanations will guide further research. We then discuss biotic stress. There is evidence that soil microbial diversity confers protection against soil-borne disease, but crop and soil type and management also play a role. Their relative importance as well as the role of biodiversity in multitrophic interactions warrant further study. Henceforth, we focus on the effects of plant and soil biodiversity on nutrient and water use efficiencies as important ecological functions in agroecosystems. The available evidence suggests that mycorrhizal diversity positively contributes to nutrient and, possibly, water use efficiency. Soil fauna effects on nutrient and water use efficiencies are also apparent, but diversity effects may be indirect, through effects on soil structure. We present a conceptual diagram relating plant and soil biodiversity with soil structure and water and nutrient use efficiencies as a framework for future studies. We then consider how cropping systems design and management are interrelated and how management options might be interfaced with farmers’ knowledge in taking management decisions. Finally, we attempt to express some economic benefits of soil biodiversity to society as part of a wider strategy of conserving and using agrobiodiversity.  相似文献   

8.
应用生态学、生态经济学、环境地学等相关理论与方法初步探讨了海岛生态系统保护与开发宏观及局部区域层面的博弈权衡评估方法:从宏观战略层面提出了综合考虑海岛生态服务价值、开发适宜性、现有开发强度三个方面重要因素的区域准则,以判断哪些无人岛可以上岛开发哪些则需禁止开发,同时还能判断哪些有人岛开发不足可作为重点开发对象,哪些则开发过度需要限制开发和优化开发;从局部区域层面提出了海岛开发之前需要重点评估的供给功能、生命支持功能、生态调节功能、信息功能、干扰调节功能等的生态系统服务功能价值以及评估方法。这些博弈权衡评估方法对指导海岛有序开发以及实现海岛生态与经济共赢具有重要意义。  相似文献   

9.
Introduction The rhizobia can change nitrogen in the air into ammonia and provide nitrogenous nutrition to the plant. This will make us independent from the use of nitrogenous fertilizers so as to minimize pollution of water tables, lakes and rivers and r…  相似文献   

10.
矿区废弃地的恢复生态学研究   总被引:11,自引:0,他引:11  
矿区废弃地的恢复生态学研究已成为恢复生态学的一个重要的研究领域。本文论述了恢复生态学的主要理论及采矿废弃地的恢复工程技术,并对矿山生态恢复中的生物多样性、景观生态学、植被生态学、生态经济学、安全经济学及可持续发展等学科领域进行了综述。  相似文献   

11.
Biomineralization, biosilicification in particular (i.e. the formation of biogenic silica, SiO2), has become an exciting source of inspiration for the development of novel bionic approaches following “nature as model”. Siliceous sponges are unique among silica forming organisms in their ability to catalyze silica formation using a specific enzyme termed silicatein. In this study, we review the present state of knowledge on silicatein-mediated “biosilica” formation in marine sponges, the involvement of further molecules in silica metabolism and their potential application in nanobiotechnology and medicine. Werner E. G. Müller dedicated this study to Prof. Vera Gamulin (Rudjer Boskovic Institute, Zagreb, Croatia) in honour of her unique contributions in molecular evolution.  相似文献   

12.
汉石桥湿地自然保护区在北京市涵养水源、调节气候以及保护生物多样性等方面发挥着重要作用。随着近年来华北地区气候暖干化、城市化,汉石桥湿地缺水问题严重,导致其生态严重退化。南水北调等输水工程缓解了北京地区的水资源紧张,为汉石桥湿地生态补水奠定了基础条件。然而,根据汉石桥湿地生态水系网络特征与生物多样性需求,制定科学、高效、可持续的生态补水方案,依然是亟待解决的问题。基于多年观测数据和实地测量结果,从水域面积、芦苇适宜生境、水文连通性3个角度探究确定湿地最适水位及对应生态补水量。研究表明,维持汉石桥正常生态功能的水位在25.7 m以上,最适水位为26.2 m。当超过最适水位后,生态补水的效用逐渐递减并趋于稳定。基于此,研究利用水动力模型对湿地的水动力过程进行模拟,发现单路补水使湿地北部水动力得到显著改善,但整体效果不佳;双路补水既能改善入水口区域水动力情况,又能提升总体水动力条件;而三入水口补水,则可以使水动力改善空间分布更均衡。该研究结果可为提升汉石桥湿地保护区生态补水效率、推进湿地生态系统的可持续发展提供理论支撑。  相似文献   

13.
盐城海岸湿地资源环境压力与生态调控响应   总被引:21,自引:0,他引:21  
江苏盐城海岸湿地拥有以保护丹顶鹤和麋鹿为特色的两个国家级自然保护区。然而强烈的人类活动贯穿于海岸湿地发育的每一个阶段,包括湿地围垦、资源酷取滥采以及环境污染等,使得该区资源环境面临的压力不断增大。通过对其资源环境特征、人口经济发展压力、湿地不合理开发利用压力以及水资源污染压力的分析,进而利用生态调控设计相应的政策措施响应方案,包括生态规划与设计---科学的生态功能区划,调整若干原缓冲区中生物多样性热点区为核心区;生态工程---生境更新与调整,建立人工湿地生态工程、芦苇生态工程、生态旅游等生态示范区;生态系统管理与能力建设---社区共管,与周围社区居民建立有效的伙伴关系。  相似文献   

14.
受城市化、工业化和地球温室效应等人类活动与自然因素的影响,美国Hackensack湿地保护区正面临着面积不断减少、景观破碎化、外来物种入侵、河水污染增加、盐碱化程度增加和范围扩大等生态胁迫。稳定湿地面积,重建湿地的复合景观,丰富生物多样性,恢复潮水的正常规律,减少水体污染,控制外来种的入侵与扩张,促进湿地原有植物的定居与扩增及原有植被的恢复是Hackensack湿地恢复的关键,也是恢复工程设计与实施的核心。退化湿地生态恢复的管理则以植被的生长、芦苇的扩散方式及动态、鱼类和蟹类的种群动态、鸟类的种类及其对生境地的利用情况对生态系统功能恢复状况进行生物检验,有效监控退化湿地生态系统的恢复动态,研究其恢复规律,进而采取相应的管理措施,科学调控生态恢复进程。  相似文献   

15.
天津的水生态问题由来已久。河流开发利用程度高、人工化程度明显、水体污染严重、天然湿地逐年减少是水生态基本特征,诸多不适宜的人类活动造成生物种类减少、地面沉降、河流干涸等问题,而水利工程的影响、水资源的过度利用、环境管理中的漏洞是导致水生态问题的主要原因。文章认为,调整水库管理方式、停止部分水坝的使用、建立切实可行的湿地保护管理模式、建立稳定的湿地保护资金投入机制以及建立湿地监测评估体系是保护管理水生态的根本途径。  相似文献   

16.
The German biologist August Weismann (1834–1914) proposed that amphimixis (sexual reproduction) creates variability for natural selection to act upon, and hence he became one of the founders of the Neo-Darwinian theory of biological evolution. He is perhaps best known for what is called “Weismann’s Doctrine” or “Weismann’s Barrier” (i.e. the irreversible separation of somatic and germ cell functionalities early during ontogeny in multicellular organisms). This concept provided an unassailable argument against “soft inheritance” sensu Lamarck and informed subsequent theorists that the only “individual” in the context of evolution is the mature, reproductive organism. Herein, we review representative model organisms whose embryology conforms to Weismann’s Doctrine (e.g. flies and mammals) and those that do not (e.g. freshwater hydroids and plants) based on this survey and the Five Kingdoms of Life scheme; we point out that most species (notably bacteria, fungi, protists and plants) are “non-Weismannian” in ways that make a canonical definition of the “individual” problematic if not impossible. We also review critical life history functional traits that allow us to create a matrix of all theoretically conceivable life cycles (for eukaryotic algae, embryophytes, fungi and animals), which permits us to establish where this scheme Weismann’s Doctrine holds true and where it does not. In addition, we argue that bacteria, the dominant organisms of the biosphere, exist in super-cellular biofilms but rarely as single (planktonic) microbes. Our analysis attempts to show that competition among genomic variants in cell lineages played a critical part in the evolution of multicellularity and life cycle diversity. This feature was largely ignored during the formulation of the synthetic theory of biological evolution and its subsequent elaborations.  相似文献   

17.
洪泽湖湿地生态系统特征及存在问题   总被引:3,自引:1,他引:2  
洪泽湖我国五大淡水湖之一,其湿地生态系统对淮河下游以及南水北调东线工程的水环境质量有重要的调节功能,由于受过境客水和季风气候的影响,形成5种湿地类型,且湿地生物多样性和生物资源极其丰富。文章在分析洪泽湖湿地生态多样性特征的基础上,分析了洪泽湖湿地存在生物多样性减少、湿地功能减退、水质下降等多种生态环境问题,认为洪泽湖湿地水位剧变、水质恶化等人为因素和自然因素是导致洪泽湖湿地功能和生物多样性退化的主要原因。  相似文献   

18.
森林生态效益补偿在改善生态环境、促进经济与社会、人与社会和谐发展过程中有着重要的现实意义,中国在这方面的立法尚不完善,在着重论述了中国森林生态效益补偿的对象和基本原则时,提出了自己的观点和看法.  相似文献   

19.
国内外生态补偿现状及其完善措施   总被引:35,自引:4,他引:31  
通过回顾发达国家(如美国、欧洲国家)和发展中国家(如中国、拉丁美洲国家)在实施生态补偿过程中采取的各种措施,发现其中存在的一些问题。在此基础上,总结了生态补偿的运行机制,提出完善生态补偿机制的措施,即:界定受偿方和支付方,明确各自的权利与义务;以机会成本为理论依据,将受偿地区生态保护与经济社会发展综合考虑,设定具有差异性的补偿标准,并将补偿分为基本补偿、产业结构调整补偿以及生态效益外溢补偿3个阶段;综合受益程度、支付能力和支付意愿确定支付方的支付标准;建立融资渠道,有效配置资金;建立生态补偿组织管理体系。生态补偿机制应以“造血式”补偿为目标,在研究中需加强生态学与经济学理论与方法的交叉。  相似文献   

20.
Industrial ecology is sometimes referred to as the science of sustainability, but unlike mature sciences, it has yet to establish reliable modes of inquiry or a uniform framework for dialogue—partly because sustainability is difficult to characterize, and partly because industry–environment interactions are difficult to model quantitatively. A number of sustainability metrics have recently been proposed that partially address the quantification problem, but inevitably oversimplify the problem of sustainability characterization. This paper proposes an overarching taxonomy for classifying the quantitative criteria of sustainability as financial, thermodynamic, environmental, ecological, socio-political or aggregated. Several examples are presented. Pollution potential, which is an environmental metric related to the ideal thermodynamic work (of mixing) per mole required to remove pollutants from the environment, is discussed in particular. However, because no single metric can capture sustainability per se, industrial ecology may be limited to elucidating the trade-offs that exist between different types of complementary (rather than substitutable) criteria. The life cycle of polyurethane foam insulation in freezer applications is presented as a quantitative example of how different environmental criteria can lead to different design recommendations. Lastly, the framework proposed herein suggests a research agenda for industrial ecology, especially regarding the linkages between different measures of sustainability and cross-comparison of the investigative methods found in different sciences related to sustainability.  相似文献   

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