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1.
漓江水陆交错带截污效果评价   总被引:2,自引:2,他引:0       下载免费PDF全文
李卓凌  王冬梅  任远 《生态学报》2018,38(21):7618-7628
水陆交错带作为水生、陆地生态系统之间的过渡带,具有拦截水体污染物、保护河流水质等重要作用。根据立地划分原则并结合广西壮族自治区漓江风景区实际情况,将漓江水陆交错带划分为6种立地类型:薄土层河滩地、中土层河滩地、厚土层河滩地、薄土层岸坡地、中土层岸坡地、厚土层岸坡地,筛选了14个指标并建立指标评价体系,利用层次分析法将漓江水陆交错带截污效果分为4个等级:优、良、中、差。评价结果如下:在漓江水陆交错带选取了20块样地,其中,薄土层河滩地占5%、中土层河滩地占10%、厚土层河滩地占10%、薄土层岸坡地占10%、中土层岸坡地占35%、厚土层岸坡地占30%,评价为"优"、"良"、"中"、"差"的样地分别占10%、60%、25%、5%,说明漓江水陆交错带整体截污效果良好,但是有少部分区域急需修复,部分区域有潜在生态危险。根据评价结果,针对不同截污效果的漓江水陆交错带,提出最佳的生态修复措施,对漓江水陆交错带生态修复工作具有指导意义。  相似文献   

2.
漓江水陆交错带土壤理化性质及其分布特征   总被引:5,自引:0,他引:5  
水陆交错带是水生生态系统与陆地生态系统之间的过渡带,是一种典型的生态交错区,承载着能量流动、物质循环和信息交换的重要作用。土壤作为水陆交错带系统的重要组成部分,是水陆交错带功能实现的基础之一。鉴于此,以桂林漓江水陆交错带纵向梯度(上游、中游、下游)不同植被覆盖条件下的土壤为研究对象,采用野外取样调查、实验分析与统计检验相结合,系统的分析了土壤理化性质及其分布特征,旨在为该区域退化生态系统恢复与重建提供依据。结果表明:11个土壤理化性质,其中5个指标(土壤含水量、全氮、全磷、速效氮和速效钾)在上游、中游和下游均差异性显著。不同梯度下的土壤理化性质的相关性及相关性大小也不尽相同,但在总体上存在一些较相似的变化规律,如上游、中游和下游的土壤容重和孔隙度均呈现显著负相关,土壤全磷和有机质与多数土壤化学性质呈显著正相关;土壤含水量在下游与多数土壤化学性质均显著相关,但在上游仅与土壤全磷显著负相关。PCA主成分分析表明,土壤容重、土壤孔隙度和土壤全磷含量的贡献均大于其他环境因子的平均贡献率,体现了它们是影响漓江水陆交错带土壤理化性质的重要环境因子。  相似文献   

3.
漓江水陆交错带不同淹没区植物多样性与土壤特征   总被引:1,自引:0,他引:1  
李扬  王冬梅  信忠保  王晶  任远  李青山 《生态学报》2015,35(15):5121-5130
针对旅游区水陆交错带出现植被退化、砾石裸露导致景观观赏度降低的问题,以广西桂林市大圩古镇水陆交错带为研究区域,按照水陆交错带淹没程度将其划分不同淹没区,并在详细调查基础上研究了各淹没区植被指标与土壤理化特征分布特征。结果表明:研究区内水陆交错带物种组成以一年生草本植物为主,物种多样性在各个不同淹没区基本呈现为先增后减的趋势,具体为轻度淹没区中度淹没区重度淹没区微度淹没区;随着水文作用的减弱,土壤砂粒含量呈现逐渐减小的趋势,粉粒和黏粒含量呈现逐渐增加趋势,土壤容重、土壤有机质含量和土壤全磷含量呈现先减后增的趋势;全氮含量呈现先增后减趋势,全钾含量在各淹没区差异不明显;研究表明大圩古镇水陆交错带土壤理化性质与植被多样性强烈地受以水位为主导的水文过程的影响与控制。扁蓄可以作为一种指示水淹时间的物种;此外,大圩古镇水陆交错带除受水文作用影响较大外,高强度旅游干扰也是重要的因素之一,植被恢复工作应兼顾生态和旅游,提升大圩古镇景观游憩度。  相似文献   

4.
随着氮素的大量人工合成,自然界氮素污染问题逐渐被关注。自然水体中经常在水陆交错带形成物质循环的热区,氮素的生物去除作用显著增加。厌氧氨氧化过程是近年来发现的重要的氮素生物去除过程,在水陆交错带氮循环中发挥重要作用。文章概述了水陆交错带氮循环热区效应的形成原因和作用机理,介绍了厌氧氨氧化作用在水陆交错带氮循环中的作用强度以及对水体氮素生物去除的贡献,并对其在生态环境领域的应用前景进行了展望。  相似文献   

5.
白洋淀水陆交错带土壤对磷氮截留容量的初步研究   总被引:19,自引:0,他引:19  
1 白洋淀水陆交错带的景观特征和土壤白洋淀地处冀中凹陷,是处于发育后期的草型富营养化湖泊。在整个湖区366km2的范围内,以芦苇植被为景观特征的水陆交错带约占36%,分布在围堤内湖边的洼地上和大小淀泊之间。其精细景观类型可划分成苇园和苇地二种类型;其中苇园约占1/3[1],主要分布在淀泊之间和近围,特征是沟壕纵横,管理精细,景观斑块类型较小,匀一化程度高;苇地约占2/3,分布在苇园外围地势较高处,连大片分布,斑块嵌接,微景观结构较复杂,多样性程度较高[1]。水陆交错带处于该湖泊和陆地系统间,是重…  相似文献   

6.
自长江干流限制无序采砂后,大量采砂船涌入鄱阳湖区作业导致水陆交错带形态与景观均发生明显的改变,人类活动深刻影响着鄱阳湖水陆交错带的稳定性。基于Landsat TM/OLI遥感影像数据,定量测算采砂活动对鄱阳湖水陆交错带形态和景观格局产生的影响,结果表明:(1)草滩与滩涂之间转化最为频繁,水域面积缩小,水陆交错带范围扩大;(2)东岸线和西岸线呈侵蚀状态,湖心岸线快速收缩;(3)鄱阳湖水陆交错带形状逐渐变得简单,而入江通道形状复杂化程度提高,其几何形态不规则化;(4)景观类型层次上,滩涂的破碎度最大,形状最为复杂,农田的破碎度和形状复杂程度最小,集聚性最强,草滩的连通性最好,沙地的景观指数幅度变化最大;(5)鄱阳湖水陆交错带破碎化程度逐渐降低,景观形状越来越复杂,景观多样性减少,整体连通性和集聚性增强;(6)采砂规模与鄱阳湖水陆交错带的形态指数呈负相关,与景观形状指数和入江通道的形态指数呈正相关,其均通过显著检验。  相似文献   

7.
水陆交错带是典型的过渡性地理空间,是地理学研究的关键样带,承载着特殊且复杂的人地关系。根据鄱阳湖过水性、吞吐型、季节性特点,考虑行政区划完整性与尺度效应,基于高分辨率遥感影像和长时间序列水位变化数据,利用非监督分类、目视解译、调查验证等方法,从自然和行政区划两个维度划分了鄱阳湖水陆交错带的地域范围,阐述了其自然、经济和社会等基本特征,分析了其理论基础、现实意义及科学内涵。研究表明:(1)鄱阳湖水陆交错带最大自然范围约为2508.08 km~2,行政范围涉及11个县(市、区)78个乡镇单元,包含行政村974个;(2)其景观要素变化多样,经济发展主要以生态农业、生态旅游业为主,人口分布呈现带状特征,与交错带范围高度吻合;(3)自然基础、尺度效应和内涵特征是其范围划分的理论基础,探究其人与环境相互作用的过程、机理与规律是重要现实意义;(4)未来可以从景观格局变化、人地关系分解、社会生活变迁等方面开展进一步研究,以揭示该区域特殊人地关系变化。  相似文献   

8.
湖滨带退化生态系统的恢复与重建   总被引:24,自引:4,他引:20       下载免费PDF全文
湖滨带是水陆生态交错带的一种类型,在湖泊流域生态系统中发挥着重要作用,具有较高的生态、社会和经济价值.湖滨带的功能包括:缓冲带功能、保持生物多样性及生境保护功能、护岸功能和经济美学价值.湖滨带退化的原因主要是人为因素引起的生物群落结构的逆向演替及生态功能下降,退化湖滨带生态恢复与重建的理论基础是恢复生态学,其生态恢复技术可划分为三大类:湖滨带生境恢复与重建技术、湖滨带生物恢复与重建技术、湖滨带生态系统结构与功能恢复技术.云南洱海湖滨带近3年的生态恢复与重建试验的生态调查结果表明,试验区水生植被得到恢复,水质净化作用明显,藻类得到抑制,浮游动物的构成和数量发生变化,湖滨带湿地生态系统的生物多样性和稳定性增加.  相似文献   

9.
城乡交错带的生态控制论分析──天津实例研究   总被引:10,自引:1,他引:9       下载免费PDF全文
胡聃  王如松 《生态学报》1996,16(1):50-57
本文应用人类生态学原理和复合生态系统理论,选择城市系统和乡村系统的交错过渡地域-城乡交错带为研究对象,对城乡交错带的概念内涵作了生态学分析。借助生态控制论原理和灵敏度模型方法,以天津城乡交错带为实例,探讨了一个具有典型社会、经济、自然复合生态边缘效应特征的人类生态系统的重庆控制论行为与机制。  相似文献   

10.
对自然状态下黑河流域中游水陆交错带湿地芦苇(Phragmites australis)种群生态特征以及地表淹水深度进行调查,分析该区芦苇种群的盖度、高度、密度和地上生物量等生态特征的季节变化和地表水位变化对芦苇种群生态特征的影响。结果表明:黑河中游水陆交错带湿地芦苇种群的生长过程具有明显季节性规律,盖度随着季节的推移呈先升高后下降的趋势,最高值出现在8月下旬,为99.7%;高度则随着季节的推移逐渐升高;密度随着季节的变化具有先升高后下降再升高的特点;地上生物量在5~6月、7~8月间增长较快,6~7月间增长相对较慢,8月下旬达到最大值,随后逐渐减少。淹水深度对芦苇种群的生态特征有显著影响,种群盖度、高度、密度、地上生物量的变化速率与淹水深度变化速率均有显著相关性(p<0.05)。  相似文献   

11.
M. M. Coelho  M. Zalewski 《Hydrobiologia》1995,303(1-3):223-228
In most types of freshwater ecosystems fish diversity depends greatly on land/inland water ecotones. So, to maintain biodiversity of fish communities in inland waters, management and restoration of aquatic terrestrial ecotones will be an important tool. However, to provide a scientific background for such conservation activities, it will be desirable to test the importance of different types of ecotones in structuring and maintaining the genetic diversity of fish populations. The relevance of population genetics data to ecotone studies can only be understood in an ecological context as evolution is a function of environment. We suggest that as ecotone complexity increases opportunities for survival of individuals, improving trophic conditions and spatial habitat heterogeneity, so the population size and variation increase with increased genetic diversity and vulnerability to environment changes decreases.  相似文献   

12.
Evidence suggests that the boundaries between rivers, floodplain wetlands, and adjacent upland communities are among the most important components of landscapes. In a landscape context, floodplain wetlands and their ecotones are important transition zones between uplands and aquatic ecosystems. Management of wetland patches and ecotones to achieve sustainable ecosystems requires action on a broad scale, giving consideration to all factors affecting wetlands and the drainage basins of which they are a part. In northeastern United States, a struggle to identify new sources of water has focussed attention on the sustainability of aquatic ecosystems.  相似文献   

13.
Bugenyi  F.W.B. 《Hydrobiologia》2001,458(1-3):33-43
Tropical water-terrestrial ecotones play important roles in regulating the flow of materials from and to land and water ecosystems. Ecotones exist where active interactions between two or more adjacent ecosystems occur with the appearance of processes that do not exist in either of the adjacent ecosystems.They occur naturally depending on the hydrological and geomorphological structure of the location. External and internal processes can influence the origin and persistence of ecotones. Ecotones regulate the landscape mosaic, affect energy flow between adjacent systems and intervene in landscape connectivity.The literature on geological and climatic origins of wetlands and open waters, internal influences on their creation and destruction and, finally, their use by society is reviewed.  相似文献   

14.
The boundary filtration effect of land/water ecotones with reed-bed/ditch systems under water level fluctuations was studied in Baiyangdian Lake of North China. It was found that the changes in reed bed areas which were primarily affected by water level fluctuations and the root channels in the wetland soils together largely determined boundary filtration efficiency. The ecotones displayed the greatest boundary effect at a moderate water level of about 8 m above sea level. The massive root channels in the wetland soils promoted water flowing into the reed beds as far as 8 m horizontally by subsurface in wet years. In dry years, when the water level was below the root channel distribution zone, the lateral water exchange width of ecotones was limited to 0.5 m along the fringe area. It is calculated that, at 8 m water level, the total boundary length of ecotones is 7,273 km and the boundary exchange volume is 5.8 × 106 m3. While at 6.5 m water level, the total boundary length of ecotones is reduced to 2,699 km and the boundary exchange volume is 1.1 × 105 m3. The standard capacity for phosphorus retention was 105.9 and 2.5 tonnes at water levels of 8 and 6.5 m, respectively. This suggests that the boundary filtration effect of reed-bed/ditch wetlands is important for improving the water quality of inland waters, and this effect should be considered in regulating and managing lake water levels.  相似文献   

15.
The reduction–oxidation (redox) state of peatland pore waters plays an important role in many peatland biogeochemical processes. Recent research has also shown that the interface between ecosystems, or the ecotone, may be responsible for a disproportionate amount of biogeochemical activity when material and/or energy is hydrologically transported between ecosystems. The purpose of this research was to examine the spatiotemporal dynamics of redox conditions across two geomorphically distinct Boreal Precambrian Shield upland–peatland ecotones to determine the spatial and temporal scales at which these ecotones may be important. Pore water chemistry of iron and sulphur species was monitored across two upland–peatland ecotones in northwestern Ontario in conjunction with hydrological measurements under both stormflow and nonstormflow conditions. In addition, one upland–peatland ecotone was instrumented to make continuous measurements of in situ redox potential (Eh) over a 12-day period to determine whether measurements at a high temporal scale could provide additional insights into the transfer of nutrients across the upland–peatland interface. Results indicated that hydrology—specifically, groundwater flowpath and the strength of the hydrological connection between upland and peatland—determined the spatial extent of the ecotone as a biogeochemical hotspot. In situ Eh measurements showed that these ecotones may be most important over a scale of only several hours and are largely affected by lateral hydrological flows from the upland. The role of both hot spots and hot moments in biogeochemistry must be considered to accurately estimate the ability of a single ecosystem to process chemical inputs.  相似文献   

16.
Dry, oligotrophic ecosystems are highly threatened in Europe due to massive changes in land use and eutrophication. The conservation of these xeric habitats has received much attention, whereas the ecotones between xeric habitats and other habitat types are often disregarded. One species which mainly inhabits the transition zone between pine forests and adjacent xeric habitats is the heath grasshopper, Chorthippus vagans. This species is endangered in large parts of Europe. One of the largest populations in northern Germany is found on a degraded inland dune near Hanover. This population is threatened by dense growth of deciduous trees and litter accumulation. We analyzed changes in the distribution of this population after the implementation of conservation measures (thinning out the forest and removal of leaf litter). Moreover, we examined dispersal distances of the species in order to assess its colonization potential. We also studied the microhabitat preferences of C. vagans to assess key factors influencing its local distribution. Our data show a substantial growth in population size, which might be a consequence of the conservation measures. New patches on the dune were colonized, promoting dispersal between the subpopulations. We propose that restoration of forest-dune ecotones should be considered more often in landscape planning and conservation management.  相似文献   

17.
This paper is an introduction to a special issue of the journal. A brief historical delineation of the question of studying interfaces between adjacent ecosystems (ecotones) is presented. High biodiversity of ecotones and their vulnerability to natural and anthropogenic impacts, including invasions of alien species, are noted. It is supposed that there is no contradiction between the ecotone and river continuum concepts. The important ecological role of amphibiotic animals and plants in interactions and functioning of the adjacent ecosystems is emphasized. The issue of studying the quantitative parameters of fluxes of matter and energy between ecosystems in conjunction with their qualitative parameters (chemical elemental and biochemical compositions) is considered in the present paper.  相似文献   

18.
The moss layer transfer technique is effective at restoring extracted peatland surfaces. However, remnant peatlands persist on the periphery of extracted surfaces. These remnant peatlands drop steeply to extracted surfaces, producing artificial ecotones that are more challenging to restore. We asked to what degree natural ecotones at undisturbed reference fens can act as models for the restoration of artificial ecotones around an extracted peatland, and whether management actions can ameliorate conditions in artificial ecotones. We compared changes in elevation, water table, peat, and multiple vegetation characteristics between natural ecotones and unmanaged artificial ecotones. We then clear‐cut peripheral strips, completely filled perimeter canals, and smoothed peripheral slopes around sections of the extracted surfaces to assess whether hydrological conditions improved. Without management, artificial ecotones are not good models of natural ecotones. The elevation gradient is steep, and water tables drop steeply within 8 m of blocked perimeter canals, with possible effects at 25 m. The consequent vegetation had denser tree saplings, faster tree growth, almost no moss cover, and low moss species richness. After these management actions, water tables increased to within approximately 5 cm of those along natural ecotones. Future study is required to assess the extent of vegetation recovery, but these results hold promise for a more holistic rehabilitation of ecotones on the periphery of extracted peatland surfaces. We present recommendations to optimize the management actions on the periphery of extracted peatlands.  相似文献   

19.
Recognition of the significance of the boundary between ecological systems, often referred to as the ecotone, has a long history in the ecological sciences and in zoonotic disease research. More recent research in landscape ecology has produced an expanded view of ecotones and elaboration of their characteristics and functions in ecosystems. Parallel research on emerging infectious diseases (EIDs) and the causes of increased rates of pathogen transmission, spread, and adaptation suggests a correspondence between ecotonal processes and the ecological and evolutionary processes responsible for zoonotic and vector-borne emerging infections. A review of the literature suggests that ecotones play a role in a number of the most important EIDs. Yet these are the only diseases for which specific landscape ecological information exists in the literature or disease reports. However, the similar disease ecologies of these with about half of the approximately 130 zoonotic EIDs suggests ecotones, particularly their anthropogenic origination or modification, may be generally associated with ecotones and the global trend of increasing EIDs.  相似文献   

20.
Aim Fog drip is a crucial water source for plants in many ecosystems, including a number of global biodiversity hotspots. In California, dozens of rare, drought‐sensitive plant species are endemic to coastal areas where the dominant summer moisture source is fog. Low clouds that provide water to these semi‐arid ecosystems through fog drip can also sharply reduce evaporative water losses by providing shade. We quantified the relative hydrological importance of cloud shading vs. fog drip. We then examined how both factors influence the range dynamics of an apparently fog‐dependent plant species spanning a small‐scale cloud gradient. Location The study area is on Santa Cruz Island off the coast of southern California. It is near the southern range limit of bishop pine (Pinus muricata D. Don), a tree endemic to the coasts of California and Baja, Mexico. Methods We measured climate across a pine stand along a 7 km, coastal–inland elevation transect. Short‐term (1–5 years) monitoring and remote sensing data revealed strong climatic gradients driven primarily by cloud cover. Long‐term (102 years) effects of these gradients were estimated using a water balance model. Results We found that shade from persistent low clouds near the coast reduced annual drought stress by 22–40% compared with clearer conditions further inland. Fog drip at higher elevations provided sufficient extra water to reduce annual drought stress by 20–36%. Sites located at both high elevation and nearer the coast were subject to both effects. Together, these effects reduced average annual drought stress by 56% and dramatically reduced the frequency of severe drought over the last century. At lower elevation (without appreciable fog drip) and also near the inland edge of the stand (with less cloud shading) severe droughts episodically kill most pine recruits, thereby limiting the local range of this species. Main conclusions Persistent cloud shading can influence hydrology as much as fog drip in cloud‐affected ecosystems. Understanding the patterns of both cloud shading and fog drip and their respective impacts on ecosystem water budgets is necessary to fully understand past species range shifts and to anticipate future climate change‐induced range shifts in fog‐dependent ecosystems.  相似文献   

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