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1.
长江河口典型湿地碳库动态研究方法   总被引:5,自引:0,他引:5  
湿地生态系统在维持碳平衡和全球气候调节中起着重要作用。长江河口湿地生态系统是国际公认的生态过程敏感区,选择长江河口典型湿地——崇明东滩作为长期碳循环观测和实验模拟的研究对象,针对长江河口湿地生态系统碳库动态研究具体的科学问题,从"土壤-植被-大气"连续体(SPAC)碳流过程监测、涡度相关法碳通量监测、植物生长控制实验(开顶式气候室,OTC)、"湿地碳循环-气候变化"生态过程模型构建、多方数据源校正等方面,总结了全球气候变化条件下长江河口湿地碳库动态的研究方法。旨在了解长江河口湿地生态系统碳库动态特征,探寻湿地碳平衡的主导控制因子,评估中国东部沿海湿地碳库对全球气候变化的响应。进而为提出长江河口湿地碳储备功能的保育策略提供理论依据。  相似文献   

2.
叶飞  陈求稳    吴世勇  蔡德所  王洪梅 《生态学报》2008,28(6):2604-2604~2613
岸边带是水-陆之间的过渡和缓冲地带,是河流生态系统的重要组成部分.岸边带对拦截径流中的固体颗粒、吸收营养盐、减少入河污染负荷有重要作用.受河流水位季节性波动的影响,岸边带生态系统的变化非常剧烈,而当水库等水工建筑的运行剧烈改变河流的水文情势时,水库下游的岸边带生态系统将受到长期的累积性影响.因此,研究复式河道岸边带植被动态对于受损河流生态修复以及河流开发运行的生态环境影响规避具有重要意义.通过原位样方观测和室内水槽模拟试验,开发了岸边带植被演替模型,该模型耦合了全局基于连续性模式的水动力模块和局部基于元胞自动机模式的植被演替模块,并以漓江中游的一段复式河道为例,通过模拟水库运行前后长序列的水文情势变化和3种岸边带植物(刺果酸模、水蓼和益母草)的生长演替,分析了为满足旅游航道需求上游水库补水运行对下游岸边带植被的影响.  相似文献   

3.
亚高山森林生态系统过程研究进展   总被引:3,自引:2,他引:1  
刘彬  杨万勤  吴福忠 《生态学报》2010,30(16):4476-4483
亚高山森林是以冷、云杉属为建群种或优势种的暗针叶林为主体的森林植被。亚高山森林在庇护邻近脆弱生态系统、保育生物多样性、涵养水源、碳吸存和指示全球气候变化等方面具有十分重要且不可替代的作用和地位,其多样化的植被和土壤组合为研究生态系统过程提供了天然的实验室。亚高山森林的群落演替与更新、生物多样性保育、水文生态过程、生物元素的生物地球化学循环以及亚高山森林生态过程对气候变化的响应等研究已取得了明显的进展。但有关全球变化条件下的亚高山森林土壤生物多样性和冬季生态学过程等研究明显不足。全球气候变化背景下的冬季生态学过程、极端灾害事件对亚高山森林生态系统过程的影响、亚高山森林生物多样性的保育机制、亚高山森林土壤生物多样性与生态系统过程的耦合机制等可能是未来研究的前沿科学问题。  相似文献   

4.
当前在全球气候变化和人类活动双重作用下,湿地正在或者将要面临着显著的盐分变化形势,尤其是内陆和滨海咸化湿地。湿地是大气甲烷的重要排放源。甲烷排放是甲烷产生、氧化和传输过程综合作用的结果。盐分变化将影响湿地水-土环境,降低植物群落初级生产力和有机物积累速率,改变微生物主导的有机物矿化速率和途径等,进而改变湿地生态系统的结构和功能,影响湿地甲烷产生、氧化、传输和排放系列过程。本文综述了盐分(浓度与组成)对湿地甲烷产生与排放的影响结果,从底物供给、微生物(产甲烷菌和甲烷氧化菌等)数量、活性与群落组成、酶活性、植物、电子受体、p H和氧化还原电位等几个关键方面分析了盐分影响湿地甲烷排放过程的内在机制。在此基础上提出了今后需重点关注的5个方面:1)加强盐分浓度与组成对湿地甲烷产生、氧化、传输与排放影响的系统性、框架性研究;2)深入探讨盐分背景、变化幅度与速率的耦合如何影响湿地甲烷系列过程;3)不同离子组成及其交互效应如何影响湿地甲烷动态过程;4)结合生物学、基因组学及同位素技术等,加强湿地产甲烷菌与甲烷氧化菌与盐分的关系及其响应研究;5)湿地甲烷对盐分变化响应的时空分异规律。  相似文献   

5.
朱耀军  郭菊兰  武高洁 《生态学杂志》2012,31(10):2681-2687
红树林湿地是地球上生产力最高的区域之一,尽管红树林的面积相对较少,但其单位面积的固碳能力很强,是重要的"蓝碳"碳库,其有机碳储量及动态对于全球碳平衡有重要影响。本文对红树林湿地有机碳(包括植被生物量碳和沉积物有机碳)的碳储量及计量方法,沉积物中有机碳的组成、来源及溯源方法,以及影响红树林湿地有机碳动态的因素等方面的研究进行了综述,并对其存在的问题和今后的研究趋势进行了分析。基于红树林湿地的固碳潜力和资源快速减少的现状,准确评估红树林碳库及其动态,有助于气候变化框架条约下的滨海湿地碳计量和价值评价,可以揭示红树林生态系统与全球变化的反馈关系,为红树林生态恢复和保护提供依据。  相似文献   

6.
 陆地生态系统对气候变化的响应及其脆弱性评价研究是当前全球变化领域的重要内容之一。该研究在生态系统过程模型的基础上,耦合了潜在 植被对气候变化的动态响应,模拟气候变化对潜在植被分布格局和生态系统主要功能的影响,以潜在植被的变化次数和变化方 向定义植被分布 对气候变化的敏感性和适应性,以生态系统功能特征量的年际变率及其变化趋势定义生态系统功能对气候变化的敏感性和适应性,进而对生态 系统的脆弱性进行定量评价,分析不同气候条件下我国陆地生态系统的脆弱性分布格局及其区域特点。结果表明,我国自然生态系统气候脆弱 性的总体特点为南低北高、东低西高,气候变化将会增加系统的脆弱性。采用政府间气候变化委员会排放情景特别报告国内和区域资源情景, 即IPCC-SRES-A2气候情景进行的预测模拟表明,到21世纪末我国不脆弱的生态系统比例将减少22%左右,高度脆弱和极度脆弱的生态系统所占的 比例较当前气候条件下分别减少1.3%和0.4%。气候变化对我国陆地生态系统的脆弱性分布格局影响不大。不同气候条件下,高度脆弱和极度脆 弱的自然生态系统主要分布在我国内蒙古、东北和西北等地区的生态过渡带上及荒漠-草地生态系统中。总体而言,华南及西南大部分地区的生 态系统脆弱性将随气候变化而有所增加,而华北及东北地区则有所减小。  相似文献   

7.
滨海湿地生态系统土壤微生物及其影响因素研究综述   总被引:3,自引:0,他引:3  
土壤微生物是滨海湿地生态系统中不可或缺的关键组分,在土壤发育、物质循环和污染物净化等诸多土壤生态过程中发挥着重要作用,对滨海湿地生态系统的维持与健康具有重大影响。系统梳理了滨海湿地土壤微生物群落结构特征和多样性,综述了土壤理化性质、植被状况、水文因素、生物入侵、全球变化、湿地开垦、石油污染等因素对滨海湿地土壤微生物的影响。在此基础上,对今后的研究重点提出了4个方面的展望:(1)加强全球变化多因子交互作用下滨海湿地土壤微生物的响应机制;(2)强化滨海湿地土壤微生物与环境因子的互作机理;(3)深化滨海湿地水动力条件对土壤微生物的影响机制;(4)开展土壤微生物与滨海湿地生态系统物质循环综合研究。研究以期为滨海湿地生态系统的保护和修复提供参考。  相似文献   

8.
大规模湿地生态恢复是一项耗资巨大、复杂的系统工程,需要以整个区域湿地结构和功能恢复作为基本目标,将时间和空间上分散的研究成果进行系统梳理,形成对区域湿地生态变化及其驱动因素的规律性认识。本研究以盐城盐沼湿地为案例,以1987年作为未干扰或干扰较少的状态,从结构-过程-功能耦合作用角度,确定区域湿地恢复的关键生态特征,包括:健康与动态潮间带湿地系统、碱蓬生态系统生产力与弹性、复杂景观镶嵌与相互作用、潮间带底栖动物丰富与鸟类觅食基地,以及濒危与关键水鸟种群保护。在此基础上,将围垦与土地利用、水管理、全球变化与海平面上升作为驱动区域湿地生态变化的三大外部因素;海岸侵蚀与沉积、区域水格局变化、地形地貌变化、湿地空间变化与连通性丧失,以及互花米草入侵等是影响湿地生态系统变化的内在压力因子;基于这些压力因子与湿地生态系统变化之间复杂作用关系分析,形成了外部驱动力-内在压力源-生态影响-生态特征之间联合作用下的区域湿地恢复概念生态模型。此模型以复杂因果关系研究为基础,直观展示了湿地恢复需要去除或减缓各种压力因子的一般路径,有利于指导大规模盐沼湿地恢复规划与实践。  相似文献   

9.
森林流域生态水文过程动力学机制与模拟研究进展   总被引:9,自引:5,他引:4  
刁一伟  裴铁璠 《应用生态学报》2004,15(12):2369-2376
水文过程是联系气候变化和森林生态系统时空变化的关键因素.未来的气候变化和人类大尺度活动将影响森林流域生态系统与水文过程的变化,森林流域生态与水文过程耦合、生态系统水文过程动力学机制研究在认识和调控生态资源及其合理利用、区域生态恢复,以及社会经济可持续方面均具有重要意义.森林流域生态系统中的水文过程可分为降雨截留、蒸散和产汇流过程.森林流域生态与水文耦合过程边界条件的确定,土壤表面特定水文过程的参数化,降雨、土壤水分运动和植被的动态耦合作用,分布式模型的应用以及森林生态水文过程动力学机制与调控等将是今后生态水文动力学过程研究的重点,综述了森林流域生态水文过程动力学机制与调控的研究进展。  相似文献   

10.
淡水湿地种子库的研究方法、内容与展望   总被引:3,自引:0,他引:3  
种子库是指存在于土壤表面和土壤中全部存活种子的总和.种子库的研究是深入探讨湿地植被结构、功能与动态等方面的重要基础,同时也是对湿地生物多样性研究的一个重要补充,对于了解植被演替动态、植被更新和受损湿地植被重建与恢复具有指导意义.本文结合国内外淡水湿地种子库研究现状,对湿地种子库的形成、研究方法以及湿地种子库时空格局、种子库与地表植被的关系、水文变化对湿地种子库的影响、湿地种子库在湿地恢复中的应用等主要研究内容进行了系统的总结;同时对湿地种子库的时间动态、种子库的分类、种子库与地表植被的关系、湿地恢复重建及湿地景观营造等研究进行了展望.  相似文献   

11.
Changhao Jin 《Hydrobiologia》2008,598(1):257-270
Freshwater wetlands worldwide are under threat from secondary salinisation and climate change. Given that many freshwater wetlands naturally have highly variable hydrology, it is important to understand the combined effects of salinity and water regime on wetland biodiversity. Here a mathematical model has been developed to explore the biodiversity dynamics of freshwater wetland ecosystems affected by secondary salinisation and seasonal hydrology variation. The model shows that seasonal hydrological change can drive the wetland ecosystem into a stable oscillatory state of biodiversity, with the same period as the wetting and drying cycle. The initial condition of a wetland mediates the ecological response of the wetland ecosystem to salinity and seasonal variability. There are two manifestations of stability that occur in relation to wetland biodiversity: monostability and bistability. In model simulations, some wetland ecosystems may respond to the effects of seasonal change quickly, while others may do so more slowly. In ‘slow response’ wetlands, seasonal variability has a weak impact on the ecosystem properties of stability, resilience, sensitivity and the species richness–mean salinity relationship. In contrast, ‘fast response’ wetlands are seasonally controlled heavily. Seasonal variability can play a critical role in determining ecosystem properties. Changes in the strength of seasonality can induce the transition between monostability and bistability. Seasonal variability may also reduce wetland resilience, exacerbating the risk of secondary salinisation. On the other hand, seasonal variability may provide opportunities for the restoration of salinised wetlands by increasing their sensitivity to management actions and facilitating recovery processes. Model simulations show that the response of the stable biodiversity oscillation to changing mean salinity is dependent on seasonality strength (primarily for fast response wetlands) and other wetland conditions. Generally, there are two types of wetland responses to changes in mean salinity: type 1 wetlands exhibit a graded response of species richness (a surrogate for biodiversity), whereas a hysteretic response occurs in type 2 wetlands. Species diversity displays critical behaviour: regime shifts in diversity occur at the thresholds of mean salinity, strength of seasonality or initial species diversity. The predictions are consistent with previously-published field observations in salinised freshwater wetlands. Handling editor: D. Hamilton  相似文献   

12.
由于人类活动、气候变化等影响,全球湿地退化不断加剧,关于湿地恢复的相关研究也越来越多,但缺乏系统的文献梳理,对研究领域的热点演变特征及发展趋势认识不足。基于文献计量学软件CiteSpace.5.5R2及中国知网(CNKI)和Web of Science核心数据库检索的文献数据,对湿地恢复领域的发文量、作者群、发文机构、文献共被引、高频关键词及突现等进行可视化分析。结果表明:(1)国内外关于湿地恢复研究的发文量总体上均呈现增长趋势,2008年之后发文量均显著提升,国内研究较国外晚了近10年,但发展迅速,国际影响力提升较快;(2)国外主要研究机构包括United States Geological Survey、Louisiana State University、University Florida、University Wisconsin等,均为美国机构,形成了以William JM-John WD、Zedler JB、Jos TA Verhoeven-Leon P M Lamers、Jeffrey WM等核心研究团队;国内以中国科学院、北京师范大学、中国林业科学研究院为主,形成了崔保...  相似文献   

13.
An integrated model describing hydrology, hydrodynamics, salt dynamics and vegetation was developed to predict the evolution of the Ciénega de Santa Clara, a non-tidal, anthropogenic wetland located in the Colorado River Delta. The Ciénega, an important part of the Delta ecosystem, is supported by saline groundwater from the U.S. that is sent to Mexico to control salinity in the U.S. The future of this water source is uncertain, and thus, the model was developed to predict how the Ciénega would respond to changes in the quantity and salinity of its inflow. Over the calibration period, 1993–2007, modeled results of wetland surface area, the fraction of the wetland covered in vegetation and salinity concentrations compare well to actual data. The model shows that between 1993 and 2007 evapotranspiration rates range from 0 to 8 mm/day, wetland surface area increases 44% from 4500 to 6500 ha, the fraction of the wetland covered in vegetation decreases slightly from 0.92 to 0.88, and the mean salinity concentration in the wetland increases from 3100 to 6700 ppm. The model was used to run nine hypothetical scenarios, representing the range of inflow quantity and salinity to the Ciénega that could occur if the source of the inflow is altered, including the possible re-opening of the Yuma Desalting plant. Model results show that the Ciénega ecosystem is more sensitive to changes in salinity than to changes in flow. However, in almost all cases, an increase in salinity and/or a decrease in flow would cause a significant decrease in vegetation cover, compromising a large portion of the habitat currently available to wildlife at the Ciénega.  相似文献   

14.
The typology of wetlands provides important information for both water resource managers and conservation planners. One of the most important aims of allocating wetlands to a certain type or class is to provide information about the ecosystem services that the wetland provides. There are two main approaches towards wetland classification. Firstly, there are top-down approaches whereby wetlands are divided into several categories based on a conceptual understanding of how the wetland functions (mostly with regards to water flows). Secondly there are bottom-up approaches whereby the classification of wetlands is based on the collection of data in the wetland that is then subjected to various clustering techniques (mostly with regards to biodiversity). The most utilized system of top-down classification assigns wetlands into hydrogeomorphic units, which function as a single unit in terms of hydrology and geomorphology. This type of classification is most useful for water resource planning, as it provides information about how the wetland is connected to the drainage network and what are the water inflows, throughflows and outflows of the wetland. The bottom-up classification approach typically focusses on the classification of wetland habitats rather than complete wetlands, where wetland habitat represents a spatial unit delineated on the basis of vegetation, embedded within the (complete) hydrogeomorphic unit, and defined as an area of wetland that is homogeneous in terms of opportunities for plant growth. At a broad scale, most ecosystem services can be superficially derived from the hydrogeomorphic unit type and the way water moves through a wetland, but habitat units and the plant species that define them would have a specific effect on the delivery of ecosystem services, for example, with different assemblages providing different resistance to flow. Some types of ecosystem services are exclusively linked to specific wetland habitats, especially provisioning services. For this reason, it is proposed that a combined approach of hydrogeomorphic classification together with a vegetation map, offers the maximum information value for ecosystem service determination. In order to account for the potential pitfall of “double counting” when combining the top-down and bottom-up approaches, each service needs to be considered individually with reference to the degree to which a service is either: (a) primarily determined by HGM class/attributes and modified by the vegetation class/attributes; or (b) primarily determined by the vegetation class/attributes.  相似文献   

15.
Wetlands are important and restricted habitats for dependent biota and play vital roles in landscape function, hydrology and carbon sequestration. They are also likely to be one of the most sensitive components of the terrestrial biosphere to global climate change. An understanding of relationships between wetland persistence and climate is imperative for predicting, mitigating and adapting to the impacts of future climate change on wetland extent and function. We investigated whether mire wetlands had contracted, expanded or remained stable during 1960–2000. We chose a study area encompassing a regional climatic gradient in southeastern Australia, specifically to avoid confounding effects of water extraction on wetland hydrology and extent. We first characterized trends in climate by examining data from local weather stations, which showed a slight increase in precipitation and marked decline in pan evaporation over the relevant period. Remote sensing of vegetation boundaries showed a marked lateral expansion of mires during 1961–1998, and a corresponding contraction of woodland. The spatial patterns in vegetation change were consistent with the regional climatic gradient and showed a weaker co‐relationship to fire history. Resource exploitation, wildland fires and autogenic mire development failed to explain the observed expansion of mire vegetation in the absence of climate change. We therefore conclude that the extent of mire wetlands is likely to be sensitive to variation in climatic moisture over decadal time scales. Late 20th‐century trends in climatic moisture may be related primarily to reduced irradiance and/or reduced wind speeds. In the 21st century, however, net climatic moisture in this region is projected to decline. As mires are apparently sensitive to hydrological change, we anticipate lateral contraction of mire boundaries in coming decades as projected climatic drying eventuates. This raises concerns about the future hydrological functions, carbon storage capacity and unique biodiversity of these important ecosystems.  相似文献   

16.
1. Reduction in diversity of both freshwater aquatic and terrestrial ecosystems has been attributed to salinity increase and such increases are a symptom of changes to land use. Hydrological alteration to ground and surface water are likely to be associated with salinity increase and its influence on biodiversity. However the combined effects of salinity and hydrology on aquatic biodiversity have not been elucidated fully in either field or experimental situations. 2. The effect of salinity and water regime on the biota in sediments from seven wetlands from inland south‐eastern Australia was tested experimentally using germination of aquatic plant seeds (five salinity and two water levels) and emergence of zooplankton eggs (five salinity levels). Salinity levels were <300, 1000, 2000, 3000, 5000 mg L?1 and water regimes were damp (waterlogged) and submerged. 3. Aquatic plant germination and zooplankton hatching was not consistent for all seven wetland sediments. Four of the wetland sediments, Narran Lakes, Gwydir Wetlands, Macquarie Marshes and Billybung Lagoon showed similar responses to salinity and water regime but the other three wetland sediments from Lake Cowal, Great Cumbung Swamp and Darling Anabranch did not. 4. As salinity increased above 1000 mg L?1 there was a decrease in the species richness and the abundance of biota germinating or hatching from sediment from four of the wetlands. 5. Salinity had a particularly strong effect in reducing germination from sediments in damp conditions when compared to the flooded conditions. In parallel, salts accumulated in the sediment in damp conditions but did not in flooded conditions. 6. There is potential for increasing salinity in freshwater rivers and wetlands to decrease the species richness of aquatic communities and thus of the wetland community as a whole, resulting in loss of wetland biodiversity. This reduction in diversity varies between wetlands and is at least partly related to hydrology. For aquatic plants the reduction in diversity will be more marked for plants germinating from seed banks at the edges of wetlands where plants are not completely submerged than for the same seed bank germinating in submerged conditions.  相似文献   

17.
EARTH University is a small agronomic university with a theme of sustainability in eastern Costa Rica. Several natural and constructed wetlands on its campus are used for research, water quality improvement, and higher education. It has become an important location for research and teaching on humid tropical wetland ecology and management. A 112-ha flow-through Raphia taedigera (Arecaceae) forested wetland is being used for climate change research, focusing on carbon sequestration and methane generation. Methane emissions are measured seasonally and are comparable to rates in tropical wetlands published elsewhere. Carbon sequestration by the wetland appears to be substantially higher than similar flow-through temperate zone wetlands. Treatment wetlands are used on campus to improve water quality of effluents from an animal farm, a dairy plant, a landfill, and a banana paper plant. Water quality was substantially improved in all of these wetlands except the landfill leachate wetland. All of these campus wetlands have been integrated into the four-year education program of EARTH University and 22 undergraduate projects have been completed on wetlands over the past 14 years.  相似文献   

18.
Geert van Wirdum 《Hydrobiologia》1993,265(1-3):129-153
A survey of base-rich wetlands in The Netherlands is presented. The main area of their occurrence is the low-lying Holocene part of the country, until some thousand years ago a large and coherent wetland landscape: the Holland wetland. The development of various parts of the Holland wetland into marshes, fens and bogs can be understood from hydrological relations in mire basins, as recognized in the distinction of primary, secondary and tertiary mire basin stages. Presently, the remnants of the Holland wetland are separate base-rich wetlands. The succession of their vegetation reflects various abiotic conditions and human influences. Three main developmental periods are distinguished as regards these factors. The first, geological period of mire development is seen as a post-glacial relaxation, with the inertia due to the considerable mass of wetland as a stabilizing factor. Biological “grazing” influences, as an aspect of utilization by humans, converted base-rich wetlands to whole new types in the second, historical period. Presently, mass and harvesting have decreased in importance, and actual successions in terrestrializing turbaries seem to reflect rapidly changing environmental conditions. Human control could well become the most important factor in the future development of wetland nature. The present value of open fen vegetation strongly depends on the continuation of the historical harvesting. The development of wooded fen may help to increase the mass of wetland in the future. Best results in terms of biodiversity are expected when their base state is maintained through water management. The vegetation and hydrology of floating fens in terrestrializing turbaries is treated in some more detail. Various lines and phases in the succession are distinguished. Open fen vegetation at base-rich, yet nutrient-poor sites is very rich in species threatened elsewhere. The fast acidification of certain such fens is attributed to hydrological and management factors. This acidification is illustrated in the profile of a floating raft sample. At the scale of these small fens, the elemental structure comprising base-rich fen, transitional fen and bog vegetation, is not as stable as it was in the large Holland wetland. A critical role seems to be played by the supply of bases with the water influx. The changing base state is supposed to change the nutrient cycling to such an extent that it would be correct to call this trophic excitation of the ecosystem, rather than just eutrophication. Eutrophication indicates a quantitative reaction to an increased nutrient supply, the internal system being unaltered. The drainage of fens, resulting in an increased productivity of the vegetation, provides another example of excitation, to the effect that the functional system is dramatically changed internally.  相似文献   

19.
湿地土壤种子库与地上植被相似性关系研究评述   总被引:3,自引:0,他引:3  
刘庆艳  姜明  吕宪国  王国栋 《生态学报》2014,34(24):7465-7474
土壤种子库与地上植被的关系是土壤种子库研究的重要组成部分。当前,湿地生态系统面临严重威胁,研究湿地土壤种子库和地上植被关系既可以加强对土壤种子库和植物群落特征的认识,又可以为湿地保护与管理提供理论指导。检索了科学引文索引扩展版(SCIE)数据库中收录的1900—2012年间研究湿地土壤种子库与地上植被关系的文献,通过分析土壤种子库与地上植被的Srensen相似性系数,结果发现:不同湿地类型的土壤种子库和地上植被的相似性存在显著差异,河流湿地中两者的相似性最小;不同植被类型中土壤种子库与地上植被的相似性差异显著:草本群落的相似性大于乔木群落;不同气候带的湿地中两者的相似性也存在显著差异,其中亚热带地区相似性最小。总结了湿地种子库与地上植被相似性关系的时空变化特征。二者的相似性通常随着植物群落的演替而减小,在空间上也随着环境梯度而变化。分析了两者关系的影响因素,如种子传播、环境条件和繁殖策略等。对研究中存在的问题及发展方向提出建议。  相似文献   

20.
Isolated wetlands are ideal model systems to examine linkages between environmental change, complex food webs, and the ecology of mosquito-borne diseases. Through long-term studies, we have evaluated the diversity among plant, invertebrate, and amphibian species of relatively undisturbed isolated wetlands. Based on preliminary evidence from impaired wetlands, we have developed a conceptual model to examine how human land use and climate change may affect wetland ecosystem functions that ultimately link to the proliferation of mosquito-borne diseases through the alteration of food webs and mosquito habitat. Our research framework initially requires the development of a wetland condition ranking system for a large group of isolated wetlands based on potential habitat for mosquitoes that vector disease. Secondly, it identifies potential changes in ecosystem function that specifically address the role of aquatic fauna in mediating mosquito-borne infectious diseases. Ultimately, understanding ecological functions and services will help focus the need for better management practices and potential regulation of impacts to isolated wetland habitats in the USA.  相似文献   

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