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阐明水鸟栖息地利用与环境因子的关系有助于制定针对性的水鸟保护对策。本研究在2012~2013年冬季对崇明东滩鸟类栖息地优化区内越冬水鸟的种类、数量以及6种环境因子(植被面积比例、裸地面积比例、水深、地形变异、栖息地结构多样性和干扰)进行调查,以了解水鸟对人工湿地的栖息地利用及其影响因子。野外调查共记录到水鸟24种9 018只,其中优势种为斑嘴鸭(Anas poecilorhyncha)和绿头鸭(A.platyrhynchos);栖息地优化区内水鸟休息的个体数量占总数量的79.2%,这表明优化区是大多数水鸟的休息地,而小(Tachybaptus ruficollis)、白骨顶(Fulica atra)、黑水鸡(Gallinula chloropus)、白琵鹭(Platalea leucorodia)和黑脸琵鹭(P.minor)的觅食个体数量超过60%,说明优化区也为这些鸟类提供了觅食地。逐步回归分析表明,裸地面积比例是影响越冬水鸟种类分布的最主要因子;尽管游禽在地形变异较大、植被面积比例较低的区域数量较多,但在休息时游禽更偏好于裸地面积比例较高的区域,而涉禽休息时偏好于地形变异较大的区域。为增加栖息地优化区内的水鸟多样性,建议在优化区内种植水鸟可食的沉水植物以增加水鸟的食物资源,同时增加裸地面积比例和地形变异程度,更好地为水鸟提供栖息地。  相似文献   
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程成  谢乔  李飞  卢刚 《动物学杂志》2019,54(5):636-645
从2015年10月至2016年6月,调查了海南岛17个沿海红树林湿地春、夏、秋、冬四季的湿地鸟类。共记录水鸟74种,隶属5目12科,其中,翘鼻麻鸭(Tadorna tadorna)为海南鸟类分布新记录种。位于海南省儋州市白马井镇洋浦湾的新英作为黑脸琵鹭(Platalea minor)新的越冬点被发现。全岛水鸟数量较多的地点在万宁小海、海口东寨港和乐东莺歌海,种类较多的地点在东寨港、东方四更和莺歌海。Jaccard指数分析表明,栖息地具有相似适合度的地方,水鸟种类相似性更高,人工湿地之间的水鸟相似性高,人工湿地与天然湿地之间的水鸟相似性低。海南岛沿海红树林湿地的鸟类种类和数量随季节变化,秋、冬季种类多、数量丰富,春、夏季的种类和数量均较少。鸻鹬类在春、冬季种类和数量占比均为最大,秋、夏季数量最多的为鹭类。Shannon-Wiener指数、Pielou均匀度指数分析得出东寨港的多样性指数最高,东寨港和莺歌海的均匀度指数表现较高。研究表明,海南岛的沿海红树林湿地是很多水鸟的重要栖息地,保护红树林是保护湿地水鸟多样性的关键。  相似文献   
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Numerous wetlands have been created spontaneously in the Ebro river basin as a consequence of new irrigation developments over the last 50 years. Water used for irrigating farmland drains into the lower parts of small valleys to form wetlands that are mostly dominated by common reed (Phragmites australis). Bird communities established in these wetlands are still simple, partly due to the lack of management to enable their ecological functions to improve. A knowledge of which environmental features favor these bird communities is essential in order to improve the design of newly created or restored wetlands associated to future irrigation developments. For this purpose, the habitat and vegetation features of 15 wetlands have been sampled. The structure of bird communities (richness, abundance and diversity) was monitored over 3 years during the breeding season and in winter at foraging and nocturnal roosting. The presence of bushes, height of stems and distance from large wetlands (>1 ha) proved to be the most influential variables on bird community structure and on most abundant species during the breeding season. Wetland area and compactness influenced species richness and the most abundant species during winter foraging and roosting. There was a maximum stem height at which only reed-dwelling birds remained. Uncontrolled winter burning had a severe negative effect upon these recently established populations. The ecological functions of newly created or restored wetlands, including those for run-off treatment in agricultural catchments, could be substantially improved taking into account simple guidelines from these results which relate bird community characteristics to wetland features.  相似文献   
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Seasonal and annual movements of Australian waterbirds are generally more complex than those of their Northern Hemisphere counterparts, and long-term data are needed to understand their relationships with climatic variables. This paper explores a long-term (1973–2002) set of waterbird counts from coastal Victoria and relates them to climatic data at local and continental scales. Three species (Black Swan Cygnus atratus, White-faced Heron Egretta novaehollandiae and Grey Teal Anas gracilis) were chosen for this analysis. Black Swans have large local breeding populations near the study region; White-faced Herons have smaller local breeding populations and Grey Teal breed extensively in ephemeral inland floodplains, such as those in the Murray-Darling Basin. All showed significant relationships with streamflow, regional rainfall and the Southern Oscillation Index (SOI) at appropriate scales and time-lags, with streamflow explaining the most variance. Black Swans showed a strong seasonal cycle in abundance and local climate variables had the greatest influence on the counts. Numbers were positively correlated with streamflow in southern Victoria three to six seasons before each count. Broader-scale climatic patterns were more important for the other two species. Numbers of White-faced Herons were positively correlated with streamflow or rainfall over various parts of Australia seven to nine seasons before each count. Numbers of Grey Teal showed weak seasonal cycles, and were negatively correlated with rainfall in Victoria or the Murray-Darling Basin in the seasons before or during each count, and positively with streamflow in the Murray-Darling Basin 15–18 months before each count.  相似文献   
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The diverse set of wetlands in southern altiplano of South America supports a number of endemic and migratory waterbirds. These species include endangered endemic flamingos and shorebirds that nest in North America and winter in the altiplano. This research developed maps from nine Landsat Thematic Mapper (TM) images (254,300 km2) to provide an inventory of aquatic waterbird habitats. Image processing software was used to produce a map with a classification of wetlands according to the habitat requirements of different types of waterbirds. A hierarchical procedure was used to, first, isolate the bodies of water within the TM image; second, execute an unsupervised classification on the subsetted image to produce 300 signatures of cover types, which were further subdivided as necessary. Third, each of the classifications was examined in the light of field data and personal experience for relevance to the determination of the various habitat types. Finally, the signatures were applied to the entire image and other adjacent images to yield a map depicting the location of the various waterbird habitats in the southern altiplano. The data sets referenced with a global positioning system receiver were used to test the classification system. Multivariate analysis of the bird communities censused at each lake by individual habitats indicated a salinity gradient, and then the depth of the water separated the birds. Multivariate analysis of the chemical and physical data from the lakes showed that the variation in lakes were significantly associated with difference in depth, transparency, latitude, elevation, and pH. The presence of gravel bottoms was also one of the qualities distinguishing a group of lakes. This information will be directly useful to the Flamingo Census Project and serve as an element for risk assessment for future development.This revised version was published online in March 2005 with corrections to the issue cover date.  相似文献   
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Participatory ecological monitoring is a realistic and effective approach in wetlands such as Alaotra, Madagascar, where important biodiversity is found in an area with high human population density. Since 2001, Durrell Wildlife Conservation Trust, government technical services, regional non-governmental organisations and local communities have collected data on key species, such as waterbirds, a locally endemic lemur and useful natural resources. The monitoring was linked with environmental quizzes and an inter-village competition, which helped raise interest in the monitoring and publicise results. The monitoring has assisted wetland management by guiding amendments to and increasing respect for the regional fishing convention, raising awareness, catalysing marsh management transfer to communities and stimulating collaboration and good governance. The sustainability of the monitoring scheme and the usefulness of the data for detecting trends and guiding local managements are discussed.  相似文献   
8.
The coastal marine environment is currently under threat from many anthropogenic pressures that were identified by the MARES project. Indicators of ecosystem health are needed so that targets can be set to guide protection and restoration efforts. Species of birds that are dependent on coastal habitats are ubiquitous along the coasts of southern Florida. Generally referred to as waterbirds, these species, although not all taxonomically related, share a common dependency on the marine environment for food, nesting habitat, or both. A suite of waterbirds was selected based on their perceived sensitivity to pressures in multiple coastal habitat types. The list of species was refined on the basis of a review of life history for characteristics that might make the species particularly vulnerable. Each selected species was then evaluated for sensitivity to the identified pressures using a hierarchical assessment that took into account the sensitivity, severity, and the temporal and spatial scales of the indicator to the given pressures. The selected suite of indicators was collectively sensitive to all the pressures except one.  相似文献   
9.
泸沽湖是中国西南重要的水鸟越冬地和旅游风景区,开展泸沽湖越冬水鸟群落组成现状调查并进行历史变化分析,对指导泸沽湖水鸟及其栖息地保护和管理具有重要意义。2013年10月至2014年2月(12月除外),逐月对泸沽湖全湖及其西北方向的竹地海湿地(距离泸沽湖约500 m,面积约0.4 km2)越冬水鸟进行调查。泸沽湖共记录到水鸟27种,观察的最大个体总数约为22 600只,符合国际重要湿地标准。泸沽湖越冬水鸟群落的主要优势物种为骨顶鸡(Fulica atra),其最大观察数约为10 300只。竹地海湿地共记录到水鸟16种,观察到的最大个体总数约为3 600只,其中赤麻鸭(Tadorna ferruginea)约为2 700只;鉴于竹地海湿地亦为水鸟聚集的栖息地,建议将其划入泸沽湖自然保护区加以保护。对比1992年的调查数据,发现泸沽湖及其附近竹地海湿地越冬水鸟的物种丰富度(species richness)可能有所下降,由原来的33种下降到现在的30种,但个体总数量相对稳定。多种涉禽和喜浅水活动的钻水鸭类(dabbling ducks)消失,可能与湖岸区旅游活动的持续进行有关;泸沽湖曾经的主要优势物种赤嘴潜鸭(Netta rufina)种群数量大幅下降,暗示泸沽湖生态系统可能已发生变化。泸沽湖旅游业进一步发展的同时,保护好现存的浅水栖息地将是泸沽湖水鸟多样性不再继续下降的关键。  相似文献   
10.
Loss of natural wetlands is a global phenomenon that has been a serious threat to the wildlife. A common practice is to construct artificial wetlands to compensate for the loss of natural wetlands. To test whether artificial wetlands as habitats for waterbirds are good alternatives to natural wetlands, we compared species richness, abundance, and seasonal dynamics of waterbird communities of natural (here tidelands) and artificial wetlands (here aquacultural ponds) on Chongming Island, China. Our results indicate that habitat preference of waterbirds showed seasonal difference: most of the shorebirds were found on tidelands in spring, whereas most of the natatorial birds were recorded in aquacultural ponds in winter. Waterbirds preferred the tidelands rather than aquacultural ponds in both spring and autumn, whereas they showed no preference for either the tidelands or the ponds in summer and winter. It is concluded that natural wetlands are better habitats for waterbirds than artificial wetlands on Chongming Island, while the artificial ones are also suitable habitats for waterbirds in winter. The waterbirds might use artificial wetlands only when natural wetlands are unavailable or of poor quality. An over-emphasis that artificial wetlands are suitable habitats for waterbirds might encourage land managers to convert natural wetlands into the artificial ones, resulting in considerable loss of bird diversity. Therefore, for the purpose of bird conservation, it would be a better practice to conserve natural wetlands rather than to construct artificial ones after destruction of natural wetlands.  相似文献   
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