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 0 毫秒
1.
大河岸线作为流域的重要生态空间,其内涵属性、空间格局和生态功能都具有显著的整体性。从岸线的陆域原真性、水陆生态渐变性、生境依存性及生物多样性等维度,分析了大河岸线生态完整性的科学内涵。结合国内外河流岸线生态评价研究,建立了大河岸线生态完整性的科学表征体系,提出各项指标评估和综合分级方法,并对长江岸线生态完整性进行了评估。结果表明,长江岸线生态完整性总体处于中等水平,从上游到下游沿岸各地市岸段生态完整性得分总体逐步降低;中上游地市岸段受到滨江湿地和洲岛发育程度及湿地保护状况等因素制约,下游地市岸段则受土地开发强度、自然岸线保有率、水陆连通性等制约。虽然中下游岸线有较高的开发程度且受长江大堤的约束,生态完整性受到明显影响,但在相同条件下生态完整性仍然有较大差异性,部分地区如铜陵段、安庆段和上海段仍保持了较高的完整性。大河岸线生态完整性的评估有助于形成既尊重自然规律、保护生态环境、保障防洪安全及供水安全,又能支撑社会经济发展、促进高效集约利用的长江生态岸线格局。  相似文献   

2.
An existing version of a fish assemblage-basedindex of biotic integrity (IBI) for the streamsand rivers of west central Mexico was testedwith independent data to validate itsusefulness as a measure of ecosystem qualityand to determine the geographic area where itis effective. Fish assemblages from 63 uplandsites in 10 basins in central Mexico(Armería, Ameca, Coahuayana, Marabasco,Purificación, Grande de Morelia, Grande deSantiago, Lerma, Balsas and Pánuco) wereassessed using the metrics and scoring criteriafrom the existing IBI and then compared withindependent evaluations of habitat and waterquality. IBI scores were congruent withhabitat and water quality values in theArmería, Purificación and Marabascobasins, where the IBI was first developed, aswell as in the adjacent Ameca and Coahuayanabasins. We conclude that the IBI can be usedwithout modification to assess environmentalquality in non-coastal streams and riverswithin these five basins. Further data areneeded from the Grande de Morelia, Grande deSantiago and middle Lerma basins, but ourresults suggest that the existing IBI may alsobe effective here. However, the existing IBIdoes not consistently reflect habitat and waterquality conditions in the Balsas and Pánucobasins and must be modified before it can beapplied there. Necessary modifications in theBalsas basin appear to be small and relatedprimarily to changes in the scoring criteriafor metrics. However, in the Pánuco basinmore substantive changes in the nature of themetrics are required. Changes in the IBI forthese basins are proposed. The IBI is nowvalidated for use in river monitoring,conservation and restoration efforts in 5basins in west central Mexico and suggestionsfor its application in other basins areavailable here.  相似文献   

3.
Pegg  Mark A.  Pierce  Clay L. 《Hydrobiologia》2002,479(1-3):155-167
Human alteration is commonplace among large rivers and often results in changes in the flow regime which can lead to changes in fish community structure. We explored the features of fish community structure, morphological characteristics, functional composition, and life-history attributes in relation to six unique flow regimes in the Missouri and lower Yellowstone rivers where we found significant differences in community composition and abundance. The clearest pattern was the distinction between the channelized portion of the river below the mainstem reservoirs and all other parts of the Missouri and lower Yellowstone rivers due to a marked reduction of species richness above the reservoirs. We also found morphological, functional, and life-history differences among the flow units, with the inter-reservoir communities consisting of slightly more generalist characteristics. Our results suggest some relation between flow and fish community structure, but that human alteration may have the strongest influence in distinguishing community differences in the Missouri and lower Yellowstone rivers.  相似文献   

4.
长江中下游四大淡水湖生态系统完整性评价   总被引:2,自引:2,他引:2  
长江中下游地区是我国淡水湖泊集中分布区域,研究该区域湖泊生态系统完整性对于湖泊生态系统保护和恢复具有重要意义。物理、化学和生物完整性指标已经广泛应用于河湖生态系统健康评价,但是缺少物理、化学和生物完整性的综合评价方法。以历史调查状况为主要参照系统,构建了基于物理、化学和生物完整性的多参数湖泊完整性综合评价指标体系,结合近年来长江中下游四大淡水湖(洞庭湖、鄱阳湖、巢湖、太湖)生态系统调查数据,对四大淡水湖生态系统完整性进行了评价。结果表明,洞庭湖、鄱阳湖、巢湖和太湖的综合得分分别为66、71、57和57。根据评价等级划分标准,洞庭湖和鄱阳湖生态系统完整性状况都达到"好"的等级,而巢湖和太湖则处于"一般"等级;结果显示,该指标能够表征人类活动对于湖泊生态系统完整性不同方面的干扰,且能够反映四大淡水湖生态系统完整性历史变化状况。因此,该方法可以作为长江中下游淡水湖泊生态系统完整性综合评价的工具并能够为湖泊生态系统的保护和恢复提供科学支撑。  相似文献   

5.
6.
7.
The riparian zone and instream habitat integrity of the Luvuvhu River were assessed based on a qualitative rating of the impacts of major disturbance factors such as water abstraction, flow regulation, bed and channel modification, etc. A system was devised to assess the impact of these factors on the relative frequency and variability of habitats on a spatial and temporal scale gauged against habitat characteristics that could have been expected to occur under conditions not anthropogenically influenced. It was found that deterioration of habitat integrity can be ascribed primarily to water abstraction. This has resulted in the cessation of surface flow in a naturally perennial river during the dry season and during droughts with consequent tree deaths and a loss of fast flowing instream habitat types in the main stem of the river. The relatively small high rainfall area in the catchment, the highly variable rainfall pattern and the occurrence of sporadic severe droughts exacerbate the impact of water abstraction on the instream and riparian habitats with expected detrimental consequences for the associated biota. The effect of water abstraction is particularly severe in the lower part of the river which flows through the Kruger National Park as no perennial tributaries join the Luvuvhu River in this section. Other factors which affect the habitat integrity of the river are the removal of indigenous riparian vegetation in some river sections, encroachment by exotic vegetation, bank erosion and stream bed modification.  相似文献   

8.
应用鱼类完整性评价体系评价辽河流域健康   总被引:28,自引:4,他引:24  
裴雪姣  牛翠娟  高欣  徐琛 《生态学报》2010,30(21):5736-5746
根据2009年8月辽河流域33个站点采集的鱼类数据(参照点8个,观测点25个),通过参数指标值分布范围、相关关系和判别能力分析,从23个侯选指标中筛选出了辽河流域的鱼类完整性指数(F-IBI)构成指标体系。该体系包括鱼类总种类数、Shannon-Wiener多样性指数、中上层鱼类百分比、底层鱼类百分比、鱼类个体总数、杂食性鱼类百分比、耐受性鱼类百分比、敏感性鱼类百分比和产粘性卵鱼类百分比共9个生物参数。分别采用1、3、5赋值法和比值法计算各站点的IBI分值,并根据参照点IBI分值的25%分位数值确定健康等级标准,对小于25%分位数值的分布范围进行3等分,提出了辽河流域河流鱼类完整性评价标准,分为健康、一般、差、较差4个等级。两种方法评价结果虽不完全相同,但趋势基本一致。Pearson相关分析表明IBI值与生境状况、水质状况、栖息地环境质量显著相关,其中与海拔、栖息地评分呈显著正相关,与CODCr、氯化物、总溶解颗粒物、含沙量、硬度、电导率呈显著负相关。  相似文献   

9.
The structure of summer fish assemblages was examined along longitudinal gradients in 31 Mediterranean-type rivers of the middle Guadiana basin (south-west Iberian Peninsula), using data from 157 sites including small streams to deep rivers. An ordination analysis, based on 16 variables, was applied to species presence, using principal component and canonical correspondence analysis. The results for the habitat data were compared with those for the biological data using a Mantel analysis, and the agreement was highly significant. Spatial structure was considered by partitioning the total variability among the environmental and geographical variables. The fish assemblages showed longitudinal zoning during the summer, with species distributed over gradients of habitat size (depth), water quality (current and physico-chemical variables), and cover (substratum and vegetation), according to their adult size and life history. The size of the habitat that remained available in summer had the greatest biological effect, being the most important factor explaining fish species distribution and assemblage structure during this stressing season. Strictly spatial variation was low, but there was still a high residual variation. Habitat associations and life-history strategies are discussed for native and exotic species.  相似文献   

10.
Starting from previous work on tropical african fishes (de Merona et al., 1983), we calculate a relationship between Loo and k and between LOO and the maximum observed length in cyprinid populations of some French great rivers and associated man-made lakes (basins of Garonne and Rhone). 45 populations are used, and they seem to conform to the model well. The growth of both groups of populations differs only by the value of some constants. This follows from differences in the individual growth pattern of fishes, climate, and from differences in food and feeding habits.  相似文献   

11.
生态系统完整性内涵及评价方法研究综述   总被引:15,自引:1,他引:15  
生态系统完整性是资源管理和环境保护中一个重要的概念.它主要反映生态系统在外来干扰下维持自然状态、稳定性和自组织能力的程度.评价生态系统完整性对于保护敏感自然生态系统免受人类干扰的影响有着重要的意义.耗散结构理论表明,外界压力和反映系统自组织能力的生物、物理、化学完整性和生态系统功能等对生态系统的完整性有良好的指示作用.本文综述了水生生态系统和陆地生态系统完整性及其所承受的压力评价指标,并探讨了优先评价指标的筛选及综合评价方法,最后根据存在的一些问题提出今后的研究展望.  相似文献   

12.
The Index of Biotic Integrity (IBI) is a measure of fish assemblage health that has been used to assess catchment and stream quality throughout North America. It reflects human perturbations on natural environmental structures and processes. While preserving the ecological foundation of the original North American metrics, we have modified and adapted the IBI to the mainstem Seine River and its major tributaries in France. This successful modification of the IBI to a considerably different fish fauna on a different continent further supports its wider use outside the midwestern United States. Using data collected in 1967, 1981, and 1988–1989 from a total of 46 sites, we show spatial and temporal variation in the Seine as indicated by IBI scores. Statistically significant relationships were found between IBI and catchment area but insignificant relationships existed between IBI and an independent Water Quality Index (WQI) based on water chemistry. Comparisons between the IBI and the WQI indicate that the former is a more sensitive and robust measure of water body quality. Our results demonstrate that the IBI, combined with a statistically designed national monitoring program, would offer a reliable means of assessing spatial patterns and temporal trends in water body improvement or degradation in France. The more primitive fish families in the Basin were affected first by perturbations. These families include all the diadromous species found in the Seine and suggest serious disruption of their life histories.  相似文献   

13.
Liu K  Zhou W  Li FL  Lan JH 《动物学研究》2010,31(5):531-538
为促进生物完整性评价法在中国的应用,加强珠江上游广西河池地区河流环境质量监测,该研究以鱼类为研究对象,初步构建了包含21个指标在内的广西河池地区河流基于鱼类的生物完整性评价的指标体系。根据鱼类调查所收集数据,结合历史资料的记录,对这些指标进行筛选和赋值,最终确立了6个指标,用于建立适合广西河池地区河流的基于鱼类的生物完整性指标体系;应用此指标体系对该地区部分河流(河段)进行了评价。评价的结果表明,小环江鱼类完整性为好;红水河、龙江和大环江为一般;刁江为极差。评价的结果与河流受人为干扰的实际情况相吻合,研究构建的评价体系可供河池周边地区使用和借鉴。生物完整性评价是水域环境质量监测的重要手段,为使生物完整性评价更加科学和客观,应加强生物完整性与环境因子之间关系的研究。  相似文献   

14.
1. Management of running waters and assessment of water quality trends require the use of biological methods. Among potential indicators, fish assemblages are of particular interest because of their ability to integrate environmental variability at different spatial scales. 2. The French Water Agencies and the Ministry of the Environment initiated a research programme to develop a fish-based index that would be applicable nation-wide. Such an index should encompass the relative importance of geographic, ecoregional and local factors influencing the distribution of riverine fishes. 3. An effective way of using the information available from fish assemblages to establish such an index is through the use of the 'reference condition approach' which involves testing a fish assemblage exposed to a potential stress against a reference condition that is unexposed to such a stress. 4. Logistic regression procedures were applied, using a fish data set of 650 reference sites fairly evenly distributed across French rivers and defined by some easily measured regional and local characteristics, to elaborate the simplest possible response model that adequately explains the observed patterns of occurrence for each species of a fish assemblage at a given site of any given river. This allows us to predict a 'theoretical' assemblage at a site. 5. The models were validated using a second independent data set of 88 reference sites. Using a third data set of 88 disturbed sites, the observed assemblages were then compared against the reference condition as defined by the 'theoretical' assemblages. The amount of deviation between the expected and observed assemblages within these sites is used as a measure of degradation. 6. This approach could be used as a framework for adapting and calibrating a multimetric index, thereby serving as a practical technical reference for conducting cost-effective biological assessments of lotic systems.  相似文献   

15.
16.
The Grassland Biome is currently one of the most threatened biomes in South Africa and is in dire need of a biomonitoring protocol. The components of ecological integrity in these ecosystems are, however, too diverse and time-consuming to measure scrupulously. It is therefore necessary to develop a set of grassland indicators that are efficient and rapid in their assessment of grassland ecosystem integrity. The South African Grassland Scoring System (SAGraSS), based on the grassland insect community, is such a suggested indicator. The present study is the first to investigate the applicability and rapidity of this proposed method. Although SAGraSS scores correlated significantly with Ecological Index values (the most commonly used index by which veld condition is evaluated in central South Africa), the method proved to be tedious and the identification of insects taxing. We offer a number of changes to make the SAGraSS method a more rapid method of assessment.  相似文献   

17.
In southwestern British Columbia (BC, Canada) and within a relatively small geographic area, lotic environments range from streams in coastal rainforests, to streams in arid continental grasslands, to very large rivers. Little is known about the invertebrate communities in large rivers in general, or in the streams of continental BC. The purpose of this study was to determine whether the benthic invertebrate community structure changes spatially between small coastal and small interior streams; between small streams versus large rivers; and whether changes in the benthic community are related to the environmental conditions. Kicknet samples and environmental data were collected from three coastal streams, three continental streams and two large rivers (discharge of 781 and 3620 m3/s, respectively). The large river sites had low invertebrate abundance, species richness and diversity, relative to the small streams. The coastal streams had the highest species richness and the continental streams had the highest invertebrate abundance. A number of taxa were specific to each class of stream. Invertebrate abundance decreased with river size, and increased with elevation, pH, conductivity, alkalinity, NO2NO3-N, total Kejldahl nitrogen and percent carbon in suspended solids.  相似文献   

18.
Surface water has been extracted from Arusha National Park (ANP) to meet human demand for over 30 years; however, there has been no evaluation of the impact of extraction on surface water quality, budget or ecological integrity. A reduction in water availability and flow is likely to also have impacts on the distribution and space use of large mammals. To assess the surface water quality and budget, 30 water sources were measured for three months over the dry and wet seasons. Nearly 70% of water is extracted, with the complete extraction of surface water common during the dry and early wet seasons. However, extraction did not lead to a decrease in downstream water quality, but wetland plant diversity was highest in areas with no surface water extraction. Extraction also influences large mammal space use: abundance along seven transects was typically higher upstream of extraction sites, especially in the case of large herbivores. Impacts of extraction therefore include the disconnection of streams, changes in space use of large mammals, decreases in plant diversity and changes in species composition of the riparian wetlands. We therefore recommend that monitoring and evaluation of extraction as well as sustainable water use practices be introduced as a matter of urgency.  相似文献   

19.
清水江的鱼类区系及生态类型   总被引:4,自引:0,他引:4  
为了系统研究清水江的鱼类区系和生态类型,在2002-2004年对清水江进行了鱼类标本的采集和生态学调查.共采集鱼类标本2 500余号,经鉴定为71种(亚种).其中中华花鳅、拟尖头鲌、长身鳜和长吻鮠等52种(亚种)鱼类为清水江鱼类新记录,而红尾副鳅、长薄鳅、海南拟、福建纹胸鮡和长须黄颡鱼则首次被发现分布于沅江水系.结合文献记录与调查表明:清水江共有鱼类4目13科57属86种(亚种),其中仅胡子鲇为外来种;清水江鱼类区系具有土著鱼类占优势、特有种类和易(濒)危种类较多、区系组成较复杂和与珠江水系之间存在着鱼类跨水系分布的现象等特点.清水江鱼类在洄游、食性、繁殖和栖息习性等方面分别属于不同的生态类型.  相似文献   

20.
An assessment of water and habitat quality, based on macroinvertebrate assemblage indices and qualitative habitat scores (QHS), was undertaken in the Honi and Naro Moru rivers, Kenya, in 2011. The two rivers are important as water sources for the local communities and as habitat for organisms such as invertebrates in the national parks there. The Naro Moru upstream site (QHS: 83%) is unmodified, with minimal human influence. The Honi downstream site and the Naro Moru midstream and downstream sites experienced moderate to large modifications in habitat and biota (QHS: 40–80%). South African scoring system (SASS) scores ranged from 43 (Naro Moru downstream) to 165 (Honi upstream), and there was a decrease in SASS scores with distance downstream. Based on the multimetric index (MI), the Honi and Naro Moru upstream and midstream sites have good water quality (MI: 0.6–0.8), whereas the Honi midstream and downstream sites, and the Naro Moru downstream site, have moderate water quality (MI: 0.4–0.6). Human activities had a negative effect on water quality and habitats. Preventive and conservation measures should be taken in the usage of the Naro Moru and Honi rivers.  相似文献   

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