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1.
上海市南汇东滩围垦后海岸带湿地冬春季水鸟生境选择   总被引:3,自引:0,他引:3  
2009年12月-2010年5月,对上海市南汇东滩围垦后城市湖泊湿地、实验修复湿地、抛荒湿地等三类人工湿地冬季雁鸭类群落和春季鸻鹬类群落展开调查,并对雁鸭类和鸻鹬类群落特征与相应生境因子进行相关分析.结果显示:三类湿地雁鸭类的种类无显著差异,但密度有显著差异:实验修复湿地是抛荒湿地的3.77倍,是城市湖泊湿地的6.03倍.鸻鹬类种类和密度:实验修复湿地分别是抛荒湿地的2.88和5.70倍.两者种类和密度差异均极显著.雁鸭类种类、密度、Shannon-Wiener多样性指数(H')与明水面面积显著正相关;种类、H'与植被面积显著负相关;种类、密度、H'均匀度与植被盖度显著负相关;H'与平均水位显著正相关.鸻鹬类种类、密度均与裸露浅滩面积显著正相关.建议对已围垦土地的利用以大中型鱼蟹塘、水田为主,以提供足够的明水面给越冬的雁鸭类栖息.通过割除植被等方法在春季提供一定的裸露浅滩面积供迁徙的鸻鹬类栖息.  相似文献   

2.
上海崇明东滩震旦鸦雀冬季种群栖息地的生境选择   总被引:3,自引:0,他引:3  
董斌  吴迪  宋国贤  谢一民  裴恩乐  王天厚 《生态学报》2010,30(16):4351-4358
2008年11月-2009年3月,在崇明东滩对震旦鸦雀(Paradoxornis heudei)种群生态进行调查研究,并对震旦鸦雀种群和生境因子的相关性进行分析。运用单因素方差对互花米草(Spartina alterniflora)入侵和芦苇(Phragmites australis)收割造成的芦苇滩涂变化进行分析,并运用多元回归的方法对震旦鸦雀种群的密度和分布以及相关环境因子进行生境选择分析。结果表明,崇明东滩震旦鸦雀种群的密度为(5.08±3.11)只/hm2;震旦鸦雀种群的密度和芦苇直径呈极显著正相关,震旦鸦雀种群的分布和芦苇的高度、密度呈极显著正相关,和食物资源量呈显著正相关;互花米草和震旦鸦雀种群的密度和分布呈显著负相关;互花米草入侵和芦苇收割降低了震旦鸦雀越冬期的栖息地质量,保留一部分生长质量较好的芦苇可以缓解震旦鸦雀冬季种群的生存压力。  相似文献   

3.
崇明东滩人工湿地春季水鸟群落结构及其生境分析   总被引:3,自引:0,他引:3  
崇明东滩处于独特的地理位置,拥有辽阔的滩涂和丰富的湿地资源,是亚太地区候鸟迁徙路线上的重要驿站。然而崇明东滩也是上海促淤圈围重点区域之一,且围垦后滩涂用作多种农业、工业发展,导致当地植物群落和滩涂湿地结构的改变,从而直接造成了鸟类生物多样性的明显下降,因此东滩湿地保护人员采取了修复和优化的治理措施,但治理同时也将自然滩涂改造成人工湿地。本研究将改造后自然滩涂作为研究不同类型人工湿地的水鸟群落结构及其生境关系的研究区域,并把研究区域分为4种不同类型人工湿地,捕鱼港优化区即一期工程(已修复)、鸟类栖息地优化区即二期工程(修复中)、人工鱼蟹塘、耀全农场。本研究目的在于分析这4种不同类型人工湿地中鸟类群落特征并寻找影响鸟类对生境利用的主要因子,同时考虑修复优化工程的保育功能,对不同管理模式下的人工湿地进行研究,从而对湿地改造提出科学的建议。由于前期大量研究表明春季鸟类数量和种类较丰富,能够较好地反映崇明东滩湿地生态现状。因此从2013年3月下旬至5月上旬在大潮期和小潮期分别对上述4种不同类型人工湿地进行了鸟类及其生境因子调查。此次鸟类调查采用样点法,共统计到水鸟2357只,隶属于6目11科45种,其中斑嘴鸭(Anas poecilorhyncha)、红骨顶(Gallinula chloropus)、金眶鸻(Charadrius dubius)、环颈鸻(C.alexandrinus)、牛背鹭(Bubulcus ibis)、鹤鹬(Tringa erythropus)、林鹬(T.glareola)等25种鸟为优势种。非参数检验分析表明,春季这4类人工湿地水鸟种类、密度、多样性均有显著性差异,一期工程内水鸟的种类、密度、多样性指数、均匀度指数都为最大。对生境因子与鸟类群落特征进行相关分析,根据非参数检验的结果得出裸露浅滩面积、水域面积、生境小岛个数是影响水鸟分布的关键因子,为此对鸟类栖息地优化区的修复及其完善提出科学建议。  相似文献   

4.
冬季水鸟对崇明东滩水产养殖塘的利用   总被引:2,自引:1,他引:2  
华宁  马志军  马强  宋国贤  汤臣栋  李博  陈家宽 《生态学报》2009,29(12):6342-6350
自然湿地的丧失和退化给依赖湿地生存的水鸟带来了严重威胁,人工湿地作为水鸟栖息地的功能日益受到关注.水产养殖塘是人工湿地的重要类型之一.通过研究崇明东滩水产养殖塘冬季水鸟群落组成及其栖息地特征,发现大面积养殖塘比小面积养殖塘吸引更多种类和更高密度的水鸟.养殖塘在放水前水位较高时吸引更多游禽栖息,而在放水后水位较低时吸引更多涉禽;在放水过程中,养殖塘中水鸟的种类最多,密度最大.另外,在放水的不同时期,不同的环境因子对水鸟群落的影响不同:放水之前,养殖塘水面面积和平均水深是水鸟种类和数量的主要影响因子,其中游禽种类和数量受水面面积影响较大,涉禽种类和数量受平均水深影响较大;放水过程中,裸地面积、芦苇面积、干扰程度、平均水深和水深变异对水鸟、游禽和涉禽的种类和数量起主要作用;放水之后,水深变异对水鸟种类和数量的影响较大,而影响游禽种类和数量的主要因子是水面面积,影响涉禽种类和数量的主要因子是水深变异.研究表明,通过对影响水鸟栖息地利用的主要因子的有效管理,养殖塘在提供经济效益的同时也能为水鸟提供适宜的栖息地.  相似文献   

5.
Grazing by microzooplankton on autotrophic and heterotrophicpicoplankton as well as >0.7 µm phytoplankton (as measuredby chlorophyll a) was quantified during July, August, October,January and April in the surface layer of Logy Bay, Newfoundland(47°38'14'N, 52°39'36'W). Rates of growth and grazingmortality of bacteria, Synechococcus and >0.7 µm phytoplanktonwere measured using the sea water dilution technique. Microzooplanktoningested 83–184, 96–366 and 64–118% of bacterial,Synechococcus and >0.7 µm phytoplankton daily potentialproduction, respectively and 34–111, 25–30 and 16–131%of bacterial, Synechococcus and >0.7 µm phytoplanktonstanding stocks, respectively. The trends in prey net growthrates followed the seasonal cycles of prey biomass, suggestingthat microzooplankton are important grazers in Newfoundlandcoastal waters. Ingestion was lowest during January and October(~2 µg C l–1 day–1) and highest in August(~20 µg C l–1 day–1). Aside from April when>0.7 µm phytoplankton represented the majority (~80%)of carbon ingested, bacterioplankton and <1 µm phytoplanktonrepresented most of the carbon ingested (~40–100%). Althoughmicrozooplankton have here-to-fore been unrecognized as an importantgrazer population in Newfoundland coastal waters, these resultssuggest that they play an important role in carbon flow withinthe pelagic food web, even at low temperatures in Logy Bay.  相似文献   

6.
崇明东滩海岸带生态系统退化诊断体系的构建   总被引:2,自引:0,他引:2  
Zhu YL  Guo ZY  Ye SF  Li XD  Wang D 《应用生态学报》2011,22(2):513-518
基于压力-状态-响应(PSR)概念模型,构建了崇明东滩海岸带农田、湿地和近海生态系统退化评价的指标体系,采用层次分析法和熵权法相结合的乘法合成法得到各评价指标的权重,并通过指标值的地理空间量化和空间聚类分析了各生态系统的退化程度.结果表明:2005年,东滩海岸带生态系统的退化程度在空间上可分为4个级区,1级区、2级区、3级区和4级区的退化程度依次加重;重金属含量的权重在近海、湿地和农田生态系统中均最大,分别为0.65、0.20和0.26;对湿地生态系统影响较大的指标还有鸟类多样性指数、土地利用强度和外来物种互花米草的盖度,其权重分别为0.26、0.16和0.10;影响农田生态系统较大的因素还有土地利用强度,权重为0.22.  相似文献   

7.
With the loss of natural wetlands, artificial wetlands are becoming increasingly important as habitat for waterbirds. We investigated the relationships between waterbirds and various biophysical parameters on artificial wetlands in an Australian urban valley. The densities (birds per hectare) of several species were correlated (mostly positively) with wetland area, and correlations were observed between certain species and other physical and water chemistry variables. Waterbird community structure, based on both abundance (birds per wetland) and density data, was most consistently positively correlated with the relative amount of wetland perimeter that was vegetated, surface area, distance to nearest wetland, public accessibility and shoreline irregularity. We also compared the relative use of the two types of urban wetlands, namely urban lakes and stormwater treatment wetlands, and found for both abundance and density that the number of individuals and species did not vary significantly between wetland types but that significant differences were observed for particular species and feeding guilds, with no species or guild being more abundant or found in greater density on an urban lake than a stormwater treatment wetland. Designing wetlands to provide a diversity of habitat will benefit most species.  相似文献   

8.
Despite the growing awareness of the important ecological functions and values provided by coastal and estuarine wetlands, wetland degradation continues worldwide due to increasing anthropogenic disturbances. Chongming Dongtan wetlands, adjacent to Shanghai, the largest city and industrial and trading port in China in rapid urban expansion and socioeconomic development are currently threatened with biodiversity reduction, wetland loss, contamination, and invasion of exotic plant. Sustainable protection and management of Dongtan Nature Reserve necessitate research to develop diagnostic tools and indicators for a comprehensive and objective assessment of wetland ecosystem health condition. Based on the pressure-state-response framework and ecological and environmental surveys at the Dongtan wetlands, an indicator system was established for evaluating the coastal wetlands ecosystem health, using indicators detected from satellite imagery and current field surveys. Through the establishment of health assessment units and spatial quantification of the indicators, the spatial clustering analysis, integrated with remote sensing and geographic information system technique was applied to make an accurate diagnosis of ecosystem health for Chongming Dongtan wetlands and highlight the areas in subhealthy and unhealthy condition and urgent need of conservation and management. The results from this research indicated that the ecosystem health condition at the Dongtan wetlands showed spatial variation, to a certain extent, corresponding to the distributions of elevation and land cover types. More than 75 % of the total study area was at a relatively healthy level, with 34.19 km2 for the very healthy zone and 41.08 km2 for the healthy zone, while the subhealthy and unhealthy zones covered 18.23 and 4.76 km2, respectively. This study demonstrated the potential for this integrated approach to give objective and effective evaluation of ecosystem health for the dynamic coastal and estuarine wetlands and provide up-to-date information to assist with early warning for ecological security and management decisions for Chongming Dongtan Nature Reserve.  相似文献   

9.
Metabolic diversity of heterotrophic bacterioplankton was tracked from early winter through spring with Biolog Ecoplates under the seasonally ice covered arctic shelf in the Canadian Arctic (Franklin Bay, Beaufort Sea). Samples were taken every 6 days from December 2003 to May 2004 at the surface, the halocline where a temperature inversion occurs, and at 200 m, close to the bottom. Despite the low nutrient levels and low chlorophyll a , suggesting oligotrophy in the winter surface waters, the number of substrates used (NSU) was greater than in spring, when chlorophyll a concentrations increased. Denaturing gradient gel electrophorisis analysis also indicated that the winter and spring bacterial communities were phylogenetically distinct, with several new bands appearing in spring. In spring, the bacterial community would have access to the freshly produced organic carbon from the early phytoplankton bloom and the growth of rapidly growing specialist phenotypes would be favoured. In contrast, in winter bacterioplankton consumed more complex organic matter originated during the previous year's phytoplankton production. At the other depths we tested the NSU was similar to that for the winter surface, with no seasonal pattern. Instead, bacterioplankton metabolism seemed to be influenced by resuspension, advection, and sedimentation events that contributed organic matter that enhanced bacterial metabolism.  相似文献   

10.
Summary Uptake rates of ammonium, nitrate and urea were measured during the EPOS leg 1 cruise to the Weddell Sea in October–November 1988 using the isotope 15N. Nitrate was the most important nitrogen source both for ice algae (f-ratio 0.88) and for phytoplankton in the water column (f-ratio 0.85). Indications of a gradual decrease in % new production with time were found in the outer marginal ice zone. Nitrogen uptake rates in ice algae from the sub-ice assemblage were light-limited at in situ irradiances. Significant regeneration of ammonium was found in ice algal samples only.Data presented here were collected during the European Polarstern Study (EPOS) sponsored by the European Science Foundation  相似文献   

11.
Abundance, depth distribution, potential productivity and respiration of periphyton on short-time (1 month) and long-time incubated strips were followed monthly during the winter–spring (January–May) transition in a shallow eutrophic lake. A taxonomic shift occurred from dominance of diatoms under ice to chlorophyte dominance in spring communities on the long-time incubated strips, while diatoms dominated until May on the short-time incubated strips. Periphyton biomass accrual was low during the ice-covered winter months (November–January: 4 mg chl a m−2 month−1), but increased to a maximum of 112 mg chl a m−2 month−1 immediately after ice-out in February. During February–April, the biomass remained constant before declining in May. Periphyton on long-time incubated strips was equally distributed in the water column in winter (January–February), but was higher near the water surface in spring (March–May). Periphyton did not change with depth on the short-time incubated strips. The potential production to respiration ratio (P/R) was negatively correlated with periphyton biomass. Throughout the study, P/R was <1 for the short-time incubated periphyton, while this was only the case in March–April for the long-time incubations. This study showed a high productive capacity of winter periphyton, resulting in accumulation of a relatively high periphytic biomass early in the season. A massive periphyton density in eutrophic lakes already in winter–spring may potentially delay or prevent the establishment and re-occurrence of submerged macrophytes in the early oligotrophication phase following a reduction of the external nutrient loading. Handling editor: Luigi Naselli-Flores  相似文献   

12.
运用经典统计学和地统计学相结合的方法,于2012年6月研究了上海市崇明东滩滨海盐土上3种人工植被表层土壤(0~20cm)水盐的空间异质性.结果表明:不同样地的土壤含水量大小顺序为:落羽杉林>狗牙根草丛>夹竹桃灌丛,其变异系数分别为13.9%、13.4%和12.9%;土壤电导率为:夹竹桃灌丛>落羽杉林>狗牙根草丛,其变异系数分别为79.2%、55.4%和15.9%;二者均属中等程度变异.不同样地土壤水盐的理论变异模型各不相同,其中土壤电导率的拟合效果更好,R2在0.97~0.99.当植被从夹竹桃灌丛→狗牙根草丛→落羽杉林,土壤含水量的空间异质性程度由弱变强,其中夹竹桃的变异性是随机的;植被从狗牙根草丛→夹竹桃灌丛→落羽杉林,土壤电导率的空间异质性由中等相关变为强相关.不同植被下土壤电导率空间自相关性多为正相关,土壤水分多呈负相关.狗牙根草丛的土壤水盐均呈条带状分布,落羽杉林地土壤水盐均呈大斑块连续状分布,而夹竹桃灌丛的土壤水分呈小斑块破碎状分布,盐分呈条带状分布.  相似文献   

13.
14.
崇明东滩湿地营养盐与重金属的分布与累积   总被引:12,自引:0,他引:12  
测定了崇明东滩湿地盐沼植物和沉积物中TN、TP、重金属Cu、Zn、Pb和Cd的含量,阐明了它们在湿地中的分布与累积特征,评估3种盐沼植物对营养盐和重金属的富集能力,并讨论了互花米草入侵对长江口湿地生态系统可能造成的影响.海三棱镳草地上部分的TN、Cu、Pb和Cd的含量均显著高于芦苇和互花米草(p<0.01),而地上部分TP和Zn却表现为:海三棱镳草和互花米草无显著性差异(p>0.05),但均显著高于芦苇(p<0.01).东滩湿地沉积物中TN和重金属的分布与累积特征为:芦苇带>互花米草带>海三棱镳草带>光滩,即随着高程的增加,沉积物中TN和重金属的含量逐步上升;但沉积物中TP含量变化不大,基本维持在0.06%左右.基于盐沼植物地上部分的生物量,估算了3种盐沼植物地上部分的营养盐和重金属库,结果表明:互花米草地上部分的养分库和重金属库均大于芦苇和海三棱镳草,表明收获互花米草对环境的净化效果最佳,特别对磷的去除效率是最高的.  相似文献   

15.
冬季火烧与收割对互花米草地上部分生长与繁殖的影响   总被引:10,自引:0,他引:10  
自1995年首次在崇明东滩发现互花米草(Spartinaalterniflora)以来,该外来种已在东滩扩张成为最具优势的植物之一。作为东滩常见的两种人为干扰,冬季火烧和收割可能会对互花米草的生长和繁殖有一定的促进作用,并可能进一步促进互花米草的入侵。因此,作者选择崇明东滩为实验地点,探讨冬季一次性火烧和收割以及相对高程对互花米草生长与繁殖的影响。结果表明:冬季火烧与收割能显著提高互花米草的植株密度和结穗率,显著降低其植株基部直径,即对其生长与繁殖有一定的促进作用,原因可能在于这两种干扰使其生境改变,光照条件得到改善;从Wilks’值的大小可看出,与相对高程相比,这两种干扰对互花米草生长繁殖的影响相对较小,而且这两种干扰对互花米草的影响差异不显著。上述结果表明,冬季火烧与收割将可能促进互花米草在东滩的入侵,有必要采取措施加以管理。  相似文献   

16.
In this study, we used comparative metaproteomics to investigate the metabolic activity of microbial plankton inhabiting a seasonally hypoxic basin in the Northwest Atlantic Ocean (Bedford Basin). From winter to spring, we observed a seasonal increase in high-affinity membrane transport proteins involved in scavenging of organic substrates; Rhodobacterales transporters were strongly associated with the spring phytoplankton bloom, whereas SAR11 transporters were abundant in the underlying waters. A diverse array of transporters for organic compounds were similar to the SAR324 clade, revealing an active heterotrophic lifestyle in coastal waters. Proteins involved in methanol oxidation (from the OM43 clade) and carbon monoxide (from a wide variety of bacteria) were identified throughout Bedford Basin. Metabolic niche partitioning between the SUP05 and ARCTIC96BD-19 clades, which together comprise the Gamma-proteobacterial sulfur oxidizers group was apparent. ARCTIC96BD-19 proteins involved in the transport of organic compounds indicated that in productive coastal waters this lineage tends toward a heterotrophic metabolism. In contrast, the identification of sulfur oxidation proteins from SUP05 indicated the use of reduced sulfur as an energy source in hypoxic bottom water. We identified an abundance of Marine Group I Thaumarchaeota proteins in the hypoxic deep layer, including proteins for nitrification and carbon fixation. No transporters for organic compounds were detected among the thaumarchaeal proteins, suggesting a reliance on autotrophic carbon assimilation. In summary, our analyses revealed the spatiotemporal structure of numerous metabolic activities in the coastal ocean that are central to carbon, nitrogen and sulfur cycling in the sea.  相似文献   

17.
18.
Per Widén 《Ecography》1987,10(2):104-109
Predation by goshawks was studied in a central Swedish boreal forest area. Data were collected in winter (January–February) 1977-81 by tracking radio-tagged goshawks, and in the breeding season (April–July) by collecting prey remains at the nest. In the breeding season birds dominated the prey, amounting to 86% of prey number and 91% of prey biomass. Wood pigeon Columba palumbus , black grouse Tetrao tetrix , hooded crow Corvus corone cornix and jay Garrulus glandarius accounted for more than 50% of the prey animals, whereas capercaillie Tetrao urogallus and black grouse accounted for more than 50% of prey biomass. There was no functional response to black grouse density fluctuations. Every year goshawks killed significantly more females than males of both capercaillie and black grouse, due to high vulnerability of the grouse hens while laying and incubating. It was estimated that during spring and early summer goshawk predation removed 25% of the female, and 14% of the male black grouse population. In winter squirrel was the dominating prey, both in terms of number (79%) and weight (56%). The proportion of squirrel in the diet was equally high both in winters of low and high squirrel density. The high proportion of squirrel in the winterdiet, as compared to the breeding season, is believed to be due to squirrels having to accept an increased predation risk in winter, in order to feed efficiently enough.  相似文献   

19.
通过分析上海崇明东滩南部冲刷带芦苇型砂壤土(A区)和东北部淤涨带芦苇/米草型粘土(B区)的有机碳含量和植被输入量,研究了异质性湿地土壤的有机碳汇聚能力,并从异质型土壤的微生物活性和理化性质的差异角度分析了造成土壤有机碳汇聚能力差异的主要原因.结果表明:A区土壤平均总有机碳含量仅为B区的46.10%(P<0.05),而A区地上部分的年均植物量仅比B区低9.16%,说明A区湿地土壤有机碳的输出量大于B区.A区细菌总数比B区高3.82倍(P<005),过氧化氢酶和转化酶活性分别比B区高4681%和3433%(P<0 05),且土壤微生物呼吸强度也高于B区.说明A区土壤的微生物碳代谢能力较强是导致其土 壤有机碳保留能力较弱的重要原因.A区砂壤土粒间孔隙较大、土壤通气透水性较好、含水 率与含盐量较低,有利于微生物生长,促进了土壤有机碳的分解;而B区的芦苇/米草型粘 土的含水量和含盐量高、微生物活性弱,有机碳氧化分解能力较低,具有较高的有机碳汇聚 能力.  相似文献   

20.
Field experiments in an area of south-western Australia where bush fly (Musca vetustissima) adults occur permanently, showed that it overwintered by continuous breeding; but only two to three generations occurred between June and September. Low survival of eggs and larvae in the food (cattle dung) from May to August was associated with rainfall rather than low temperatures. High egg-adult survival occurred in late August; lower egg and larval survival in September and early October was attributed partly to dung fauna. Egg and larval survival was high in late October until December but predation or parasitization caused low survival of puparia outside the dung. Experimental and wild adult flies were largest and therefore most fecund in early spring; smaller wild flies in late spring appeared to result from larval competition for food. Simultaneous high egg-adult survival, high fecundity and rapidly decreasing generation times in late winter and early spring provide a basis for explaining the major increase in adult bush fly abundance observed in some areas in mid-spring.  相似文献   

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