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1.
2008年12月至2009年1月及2011年12月至2012年1月先后两次对钦州湾的越冬鸻鹬类进行了调查,对越冬鸻鹬类退潮后在各类型生境的分布情况和原因进行了分析,以期为制定有效保护越冬鸟类及其生境的措施提供科学依据。结果表明,在不同的天气情况下退潮后各生境内记录到的鸻鹬类物种数和种群数量均不同,钦州湾不同生境鸻鹬类结构特征随天气变化改变。相似性比较显示,晴天各生境中鸻鹬类相似性指数最高的是盐田-养殖塘生境和农田生境,相似性指数为0.96;鸻鹬类相似性指数最低的是红树林滩涂生境和光滩生境,相似性指数为0.49。阴冷天气各生境中鸻鹬类相似性指数最高的是光滩生境和盐田-养殖塘生境,相似性指数为0.79;最低是红树林滩涂生境和光滩生境,相似性指数为0.52。分析表明人类活动的干扰对越冬鸻鹬类生境选择的影响较大。 相似文献
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《四川动物》2013,(6)
2012年1月至2013年5月在滇池湿地34个样点上开展了每月1次(共17次)的鸟类调查。迄今为止,滇池湿地共发现鸻鹬类850只次,隶属于5科11属20种。其中,铁嘴沙鸻Charadrius leschenaultia和弯嘴滨鹬Calidris ferruginea为云南鸟类新分布;水雉Hydrophasianus chirurgus和蒙古沙鸻Charadrius mongolus为滇池鸟类新纪录。有18种(731只次)鸻鹬类集中分布在滇池整治过程中形成的福保湾湿地。福保湾湿地大面积浅水泥滩、开阔水域和稠密植被,交错形成了鸻鹬类偏好的生境格局,是导致3种鸻鹬类新分布和大量鸻鹬类个体集中分布的主要原因。 相似文献
3.
在长江口南岸杭州湾北岸滨海滩涂进行了鸻形目鸟类的资源调查,以及鸟类栖息地选择模式分析,2004年3月至2005年1月共统计到鸟类25种,春季优势种为大缤鹬(Calidris tenuirostris)、尖尾缤鹬(Calidris alpine)和红颈滨鹬(Calidris ruficollis);夏季为环颈(Charadrius alexandrinus)、青脚鹬(Tringa nebularia)和蒙古沙(Charadrius mongolus),秋季为环颈、红颈滨鹬和青脚鹬,冬季为黑腹滨鹬(Calidris alpina)、环颈和泽鹬(Tringa stagnatilis),鸟类总体数量呈春季>秋季>冬季>夏季,海堤外(自然滩涂)和堤内(人工湿地)鸟类种数四季大致相等,但鸟类平均密度季节差异显著。通过对样点内鸟类与环境因子进行多元分析,初步总结出堤外滩宽和光滩宽是影响鸟类栖息的最关键因子,海三棱草(Scirpus× mariquete)覆盖比例和潮上坪宽度的影响程度次之。堤内浅水塘比例和裸地比例是影响形目鸟类分布的关键因子,海三棱草覆盖比例也起正向作用。而人类干扰大、芦苇(Phragmites communis)/互花米草(Spartina alternifloral)密植和高水位的区域不利于鸟类利用。 相似文献
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生境破坏是目前野生动物保护面临主要问题,加强生境恢复与重建对保护珍稀物种具有重要意义.将3S技术运用到北戴河地区鸻形目鸟类觅食生境评价中,分析了近20a(1987～2006年)北戴河地区鸻形目鸟类觅食生境的动态变化,结果:鸻形目鸟类最适宜觅食生境和适宜觅食生境分布面积在1993年最大;觅食生境变化以1993年为分水岭;最适宜觅食生境和适宜生分布面积呈下降趋势(倒U形分布),不适宜觅食生境分布面积呈增加趋势(U形分布).北戴河地区鸻形目鸟类觅食生境变化主要影响因素是人类活动增加. 相似文献
5.
崇明东滩为东亚-澳大利西亚鸻鹬类迁徙路线上的重要迁徙停歇地.本文通过分析崇明东滩回收的异地环志鸻鹬类记录及异地回收的崇明东滩环志的鸻鹬类记录,研究崇明东滩鸻鹬类的迁徙路线.1979～2008年间,崇明东滩共回收到来自澳大利亚西北部、澳大利亚维多利亚、美国阿拉斯加及新西兰北岛等17个国家与地区环志的鸻鹬类265只,包括大滨鹬(Calidris tenuirostris)、斑尾塍鹬(Limosa lapponica)、红腹滨鹬(C.canutus)等16种鸟类,其中春季北迁期间的记录占总数的93%;2003～2008年间,澳大利亚西北部、新西兰南岛、中国大陆及新西兰北岛等10个国家与地区回收到崇明东滩环志的大滨鹬、斑尾塍鹬、红腹滨鹬等12种鸟类,共计164只.在所有与崇明东滩鸻鹬类存在迁徙连接的20个国家和地区中,澳大利亚西北部的回收记录占全部回收记录的55%.根据斑尾塍鹬和红腹滨鹬不同亚种的越冬地分布,崇明东滩回收的斑尾塍鹬有L.l.menzbieri与L.l.baueri两个亚种,红腹滨鹬有C.a.piersmai和C.a.rogersi两个亚种. 相似文献
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钦州湾浮游植物周年生态特征 总被引：6，自引：0，他引：6
2008-2009年对钦州湾及附近海域进行4个季节航次的浮游植物调查,共鉴定出浮游植物131种,其中硅藻种数最多,达101种,占浮游植物总种数的77.1％;甲藻次之,23种;其他种类3门7种.浮游植物以广温性种和暖水性种为主.总种类数的季节变化与硅藻种类数均为春季最低,夏、秋、冬依次增加,冬季最高.各季节浮游植物丰度为232.28×104～ 977.0×104 cell·m-3,平均为558.57×104 cell·m-3;各季节浮游植物丰度呈现夏、春、冬和秋依次减少的趋势;各区域浮游植物丰度四季均为由内湾至外湾先升高、到湾外逐渐降低的趋势,但在夏季其高丰度区由外湾南移至湾口附近.浮游植物群落的Shannon多样性指数和均匀度指数平均值分别为3.18和0.63,多样性水平较高.浮游植物丰度与温度、盐度、溶解性无机氮及活性磷酸盐的相关关系因季节而变化. 相似文献
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2008-2009年对钦州湾及附近海域进行4个季节航次的浮游植物调查,共鉴定出浮游植物131种,其中硅藻种数最多,达101种,占浮游植物总种数的77.1%;甲藻次之,23种;其他种类3门7种.浮游植物以广温性种和暖水性种为主.总种类数的季节变化与硅藻种类数均为春季最低,夏、秋、冬依次增加,冬季最高.各季节浮游植物丰度为232.28×104～977.0×104 cell·m-3,平均为558.57×104 cell·m-3;各季节浮游植物丰度呈现夏、春、冬和秋依次减少的趋势;各区域浮游植物丰度四季均为由内湾至外湾先升高、到湾外逐渐降低的趋势,但在夏季其高丰度区由外湾南移至湾口附近.浮游植物群落的Shannon多样性指数和均匀度指数平均值分别为3.18和0.63,多样性水平较高.浮游植物丰度与温度、盐度、溶解性无机氮及活性磷酸盐的相关关系因季节而变化. 相似文献
9.
三峡库区青干河峡谷鸳鸯越冬生境选择初探 总被引：2，自引：0，他引：2
从影响动物生境选择的水、食物、隐蔽物和干扰等因子对2010年11～12月在青干河首次发现的62只越冬鸳鸯新的越冬地环境进行了初步分析。结果表明:随着三峡水库蓄水至175m,长江支流青干河尾水段面积扩展及其他适宜水环境条件为越冬鸳鸯提供了良好生境;青干河及两岸分布的陆生植物及水生动植物为鸳鸯越冬提供了一定食物来源;两岸茂密的植被为鸳鸯陆上及水面的栖息提供了良好的隐蔽条件;人为干扰的负面影响较小成为鸳鸯越冬生境选择的重要因素。 相似文献
10.
以群落生态学的原理为基础 ,研究景观特征及异质性变化导致鸟类群落的变化 ,重点探讨了人为干扰导致的景观特征变化对迁徙鹬群落时空结构的影响。景观异质性的改变是引起鹬群落结构变化的主要原因 ,也是决定鹬群落分布的重要因子。围堤内湿地植被覆盖率大于 6 0 %或水面小于总湿地面积 2 0 %后 ,鹬基本不出现 ,必须含有水域、植被和裸地三种景观要素。植被覆盖率为 1 0 %～ 2 0 %时 ,鹬数量最多。鹬在围堤内滩涂的分布与底栖生物量无关。水深是影响鹬分布的重要因素 ,使鹬的空间生态位得到分离。科鸟类主要活动在裸地和浅水区 ,中小型鹬类主要在中水区 ,大中型鹬类在深水区。科学管理围堤封堵后滩涂 ,控制和改造湿地景观 ,将在一定程度上降低围涂工程对鹬群落的负面效应。 相似文献
11.
Aim Resource‐selection functions (RSFs) can quantify and predict the density of animal populations across heterogeneous landscapes and are important conservation tools in areas subject to human disturbance. Sandy beach ecosystems have comparatively low habitat heterogeneity and structural relief in the intertidal zone, but intense human use. We aimed to develop predictive RSFs for birds on ocean‐exposed sandy beaches at two spatial scales, 25 ha (local scale) and 250 ha (landscape scale), and to test whether habitat selection of birds that commonly use the surf–beach–dune interface is influenced by the rates of human activities. Location Moreton and North Stradbroke Island, eastern Australia. Methods Avifauna and human activities were mapped on three sandy beaches covering 79 km of coastline for 15 months. Habitat characteristics of the surf–beach–dune interface were derived from remote sensing and ground surveys. RSFs were developed for 12 species of birds at two spatial scales: 25 ha (local scale) and 250 ha (landscape scale). Results At local (25 ha) and landscape scales (250 ha), dune dimensions and the extent and type of vegetation structure were important predictors of bird density. Adding the frequency of human activities improved the predictive power of RSFs, suggesting that habitat selection of birds on beaches is modified by human use of these environments. Human activities occurred mostly in the mid‐ to lower intertidal zone of the beach, overlapping closely with the preferred habitats of Silver Gulls (Larus novaehollandiae), Pied Oystercatchers (Haematopus longirostris), Red‐capped Plovers (Charadrius ruficapillus) and endangered Little Terns (Sternula albifrons). Main conclusions In addition to demonstrating the appropriateness of RSFs to the surf–beach–dune interface, our results stress the need for systematic conservation planning for these ecosystems, where ecological values have traditionally been subsidiary to the maintenance of sand budgets and erosion control. 相似文献
12.
Coastal regions are important habitats for migratory shorebirds. The aim of the study is to understand habitat use by migratory shorebirds and to develop a conservation strategy in the sustainable use of wetlands. From March 2004 to January 2005, we conducted a seasonal shorebirds census in ten coastal habitats along the South Yangtze River mouth and North Hangzhou Bay, simultaneously examining the relative seasonal abundance of shorebirds and their spatial distribution. A total of 25 species were identified, the dominant seasonal species were Great Knot (Calidris tenuirostris), Sharp-tailed Sandpiper (Calidris alpine) and Red-necked Stint (Calidris ruficollis) in spring; Kentish Plover (Charadrius alexandrinus), Common Greenshank(Tringa nebularia) and Lesser Sand Plover (Charadrius mongolus) in summer; Kentish Plover, Red-necked Stint and Common Greenshank in autumn; Dunlin(Calidris alpine), Kentish Plover and Marsh Sandpiper (Tringa stagnatilis) in winter. These species accounted for more than 85% of the total shorebirds. The numbers of shorebirds counted was highest in spring and then in autumn, winter and summer respectively. Among the four seasons, there were few significant differences in the number of bird species between the sites outside the seawall (intertidal mudflat) and the sites inside the seawall (artificial wetland), but the average density of shorebirds was obviously different. The habitat-selection analysis of the environmental factors (outside and inside the seawall) impacting on the shorebird community was made in the 10 study sites with Canonical Correspondence Analysis. The study results indicated that: (1) Outside the seawall, the widths of the total intertidal mudflat and bare mudflat were the key factors affecting the shorebirds; the proportion of bulrush (Scirpusmariquete) covering and supertidal mudflat width had a positive correlation with the abundance of birds, while human disturbance and the proportion of both reed (Phragmites communis) and smooth cord-grass (Spartina alterniflora) covering in total surveyed areas had negative impacts on bird numbers; (2) Inside the seawall, the proportions of areas with shallow water and mudflats occupying the total surveyed area were key factors influencing the number of birds; the size of the bulrush area should have a positive impact on the appearance of shorebirds. Habitats with heavy human disturbance, dense reed and smooth cord-grass or a high water level were not conducive to be inhabited by shorebirds. 相似文献
13.
Coastal regions are important habitats for migratory shorebirds. The aim of the study is to understand habitat use by migratory shorebirds and to develop a conservation strategy in the sustainable use of wetlands. From March 2004 to January 2005, we conducted a seasonal shorebirds census in ten coastal habitats along the South Yangtze River mouth and North Hangzhou Bay, simultaneously examining the relative seasonal abundance of shorebirds and their spatial distribution. A total of 25 species were identified, the dominant seasonal species were Great Knot (Calidris tenuirostris), Sharp-tailed Sandpiper (Calidris alpine) and Red-necked Stint (Calidris ruficollis) in spring; Kentish Plover (Charadrius alexandrinus), Common Greenshank(Tringa nebularia) and Lesser Sand Plover (Charadrius mongolus) in summer; Kentish Plover, Red-necked Stint and Common Greenshank in autumn; Dunlin(Calidris alpine), Kentish Plover and Marsh Sandpiper (Tringa stagnatilis) in winter. These species accounted for more than 85% of the total shorebirds. The numbers of shorebirds counted was highest in spring and then in autumn, winter and summer respectively. Among the four seasons, there were few significant differences in the number of bird species between the sites outside the seawall (intertidal mudflat) and the sites inside the seawall (artificial wetland), but the average density of shorebirds was obviously different. The habitat-selection analysis of the environmental factors (outside and inside the seawall) impacting on the shorebird community was made in the 10 study sites with Canonical Correspondence Analysis. The study results indicated that: (1) Outside the seawall, the widths of the total intertidal mudflat and bare mudflat were the key factors affecting the shorebirds; the proportion of bulrush (Scirpus×mariquete) covering and supertidal mudflat width had a positive correlation with the abundance of birds, while human disturbance and the proportion of both reed (Phragmites communis) and smooth cord-grass (Spartina alterniflora) covering in total surveyed areas had negative impacts on bird numbers; (2) Inside the seawall, the proportions of areas with shallow water and mudflats occupying the total surveyed area were key factors influencing the number of birds; the size of the bulrush area should have a positive impact on the appearance of shorebirds. Habitats with heavy human disturbance, dense reed and smooth cord-grass or a high water level were not conducive to be inhabited by shorebirds. 相似文献
14.
Gunnarsson TG Sutherland WJ Alves JA Potts PM Gill JA 《Proceedings. Biological sciences / The Royal Society》2012,279(1727):411-416
The capacity of species to track changing environmental conditions is a key component of population and range changes in response to environmental change. High levels of local adaptation may constrain expansion into new locations, while the relative fitness of dispersing individuals will influence subsequent population growth. However, opportunities to explore such processes are rare, particularly at scales relevant to species-based conservation strategies. Icelandic black-tailed godwits, Limosa limosa islandica, have expanded their range throughout Iceland over the last century. We show that current male morphology varies strongly in relation to the timing of colonization across Iceland, with small males being absent from recently occupied areas. Smaller males are also proportionately more abundant on habitats and sites with higher breeding success and relative abundance of females. This population-wide spatial structuring of male morphology is most likely to result from female preferences for small males and better-quality habitats increasing both small-male fitness and the dispersal probability of larger males into poorer-quality habitats. Such eco-evolutionary feedbacks may be a key driver of rates of population growth and range expansion and contraction. 相似文献
15.
通过2008年~2009年在钦州湾及附近海域进行的4个航次的大型底栖动物调查,共获大型底栖动物8门62科94种,软体类最多,其次为多毛类,种类季节变化较大。以优势度指数Y>0.02为判别标准,调查区春季优势种为方格皱纹蛤（Periglypta lacerata (Hanley)）、刺足掘沙蟹（Scalopidia spinosipes Stimpsom）和独齿围沙蚕（Perinereis cultrifera Grube）,夏季优势种为方格皱纹蛤、刺足掘沙蟹和持真节虫,秋季优势种为曲波皱纹蛤和网纹藤壶,冬季优势种为肋鲳螺和方格皱纹蛤。春、夏季优势种变化不大,秋、冬季优势种变化较大,除方格皱纹蛤外均为季节特有种。海区底栖生物平均总密度和平均总生物量分别为439ind./m2和115.14g/m2。与20世纪80年代钦州湾茅尾海调查结果相比,平均栖息密度有所升高,但是平均生物量却有较大程度的降低。底栖动物群落的丰富度指数（D）、Shannon-Wiener多样性指数（H′）和均匀度指数（J′）平均值分别为4.01、1.80和0.73,水平不高。用SPSS软件将各站大型底栖动物的平均密度、平均生物量、多样性指数等生态特征值与水深等理化因子进行了Pearson相关分析,结果表明春季各特征指数与环境因子相关性不显著;夏季丰度、多样性指数和均匀度指数均与水深呈显著负相关,种类数、丰富度和多样性指数与沉积物pH呈显著负相关;秋季密度与硫化物呈显著正相关;冬季生物量与硫化物和有机质均呈显著正相关。 相似文献
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Abstract Broadscale habitat use by Eastern Curlews (Numenius madagascariensis) in their non‐breeding range in eastern Australia was assessed using low tide surveys on feeding grounds, where 60 skilled volunteers made repeated counts of the birds on intertidal flats, across 41% (9500 ha) of the intertidal habitat within Moreton Bay, Australia. We analysed 32 defined sections of intertidal flat, of roughly equal area (mostly 200–400 ha), which varied greatly in their curlew density (2–47 birds per 100 ha) and also in substrate and other environmental features. Sites with the least resistant substrates had densities three times those with the most resistant substrates. Of 10 environmental characteristics measured for each site, substrate resistance was the best predictor of curlew density (r2 = 0.45). Characteristics that were poor predictors included distance to the nearest roost, level of human disturbance and distance to urban settlement. For a finer‐scale assessment, microhabitat use and feeding behaviour were recorded during low tide within 12 intertidal flats, which varied in size (23–97 ha), substrate, topography and other features. Across all flats, curlews strongly preferred to feed relatively close (0–50 m) to the low‐water line. They fed on a variety of substrates (including sand, sandy‐mud, mud and seagrass) in broadly similar proportions to their occurrence in the habitat. There was a statistically significant preference for sand, although its magnitude was not strong. These results indicate that curlews select habitat most strongly at a between‐flat rather than within‐flat scale. 相似文献
18.
Few studies have assessed how the dynamics of wetland bird movements relate to changing resource availability, particularly at more than one spatial scale. Within western Oregon's Williamette Valley, we examined winter resident Dunlin Calidris alpina movements in relation to a decrease in availability of preferred shorebird foraging habitat from early to late winter of 1999–2000. By tracking movements of 15 (early winter) and 12 (late winter) radiomarked individuals, we calculated home ranges and characterized presence/absence of a preference for shorebird foraging habitat during each winter period. Between periods, we compared: (1) percentage of shorebird habitat in home ranges to its availability in the landscape (regional preference), (2) percentage of radio locations in shorebird habitat to its availability within home ranges (local preference) and (3) relative use of roost sites. Concurrent with a 75% decrease in available shorebird habitat from early to late winter, average home range sizes increased by a factor of 3.8. At a regional scale, home ranges in early winter included a significantly greater percentage of shorebird foraging habitat than was available in the wider landscape. However, by late winter, the percent of shorebird habitat in home ranges did not match availability in the landscape. At the local scale, for both winter periods Dunlin were located in shorebird foraging habitat more often than expected given availability of habitat within home ranges [Correction added after online pub-lication 23 May 2008: sentence amended]. An increase in the number of roosts used from early to late winter implies possible reliance on additional sites in late winter for foraging opportunities. Results suggest that wet, unvegetated habitat is sought by Dunlin throughout winter, but individuals could not select home ranges in late winter that fully compensated for seasonal loss of habitat. 相似文献
