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1.
河口区大型底栖动物具有的重要群落特征往往可以反映群落所经历的环境污染。为更好地了解珠江河口区大型底栖动物群落结构, 作者于2014年11月至2015年8月进行了4个季度的大型底栖动物调查, 并利用PRIMER 6.0软件进行群落生物多样性指数计算、群落等级聚类(Cluster)和非度量多维标度排序(nMDS)分析。研究结果显示: 珠江河口区共获得大型底栖动物52种, 优势种包括光滑河篮蛤(Potamocorbula laevis)、中国绿螂(Glaucomya chinensis)、焦河篮蛤(Potamocorbula ustulata)和羽须鳃沙蚕(Dendroneris pinnaticirrus)。大型底栖动物年平均密度为269.3 ind./m 2, 年平均生物量为129.61 g/m 2。12个站次的丰富度指数(D)、均匀度指数(J')和Shannon-Wiener多样性指数(H')平均值分别为1.81 ± 1.38、0.50 ± 0.27和1.60 ± 1.13。该结果显示除P01断面的秋季和冬季环境质量为优良外, 其他站位在不同季度都显示出轻度到重度的污染。Cluster聚类分析和nMDS标序结果表明, P01断面与P02和P03断面群落相似度较低, 与断面地理分布情况一致; P02断面和P03断面存在交叉聚集, 群落相似度较高。结合环境因子结果可知, 沉积物理化因子与群落分布特征相关性较大, 其中最能解释珠江河口区群落多样性分布特征的环境因子为盐度和pH值。  相似文献   

2.
Over the past decade international organizations and developing countries have been trying to promote agricultural diversification among smallholders under the assumption that smallholders are too dependent upon a narrow range of crops. The International Coffee Organization and the Government of Indonesia have promoted agricultural diversification among coffee farmers to curb production and, thereby, increase prices. In South Sumatra, Indonesia, coffee smallholders diversify on their own initiative and depend upon numerous resource systems. They diversify out of coffee and even agriculture because other investments yield attractive returns and because further diversification within agriculture is often limited by agronomic and financial constraints.The Center for Policy and Implementation Studies (CPIS), Ministry of Finance, in Indonesia funded this research.  相似文献   

3.
长江口附近海域大型底栖动物群落特征   总被引:29,自引:0,他引:29  
利用2002年9月在长江口附近海域进行的大型底栖动物定量采集样品,采用物种优势度计算方法和大型多元统计分析软件PRIMER,研究了该海域大型底栖动物群落的优势种组成和物种多样性、生物量和丰度、群落等级聚类分析(CLUSTER)和非度量MDS标序以及群落受污染扰动情况。本次调查共获得长江口附近海域大型底栖动物154种,其中多毛类环节动物60种,甲壳动物30种,软体动物28种,棘皮动物25种,其它类群动物11种。群落中优势种的地位都不明显,只有虫(Listriolobussp.)、豆形短眼蟹(Xenophthalmus pinnotheroidesWhite)、拟单指虫(Cossurella dimorphaHartman)为相对重要的种类。栖息种数、平均生物量和丰度以及3个多样性指数H′、D和J的空间分布无明显的规律,在122°E以东海域呈不连续的斑块或镶嵌状分布。群落结构聚类分析和MDS标序表明,20个取样站的群落结构相似性程度都非常低,为10%-30%,仅有A12和E4两个站Bray-Curtis相似性系数达到50%。ABC曲线表明,近长江口的A4站和A14站的底栖动物群落已有受到一定程度的轻微污染扰动的趋势;而距长江口较远的P9和P5两站ABC曲线状况正常,表明该处的大型底栖动物群落尚未受到干扰。  相似文献   

4.
陈国贵  王文卿  谷宣  洪伟  林宇枫  王瑁 《生态学报》2021,41(11):4310-4317
在城市化的背景下,探明不同大型底栖动物群落对植物群落变化的响应,对红树林生态系统的健康评价和退化生态系统的修复具有重要意义。以福建漳江口国家级红树林自然保护区为研究对象,揭示红树植物群落周转对不同大型底栖动物群落结构(蟹类和软体动物)的影响,并分析其与环境参数的关联性。结果表明:在1.6 km的地理尺度上,漳江口红树林湿地的环境变化较大,表现出7.19个环境梯度。在此地理尺度的环境梯度上,红树植物群落由5种红树植物组成,其平均周转率为76%;软体动物群落由12种软体动物以模块化和非随机的方式聚集,其平均周转率为83%,并随红树植物群落周转出现显著非线性增加,盐度和老鼠簕(Acanthus ilicifolius)周转是其主要影响因素;蟹类群落则由20种蟹类以更高的模块化和非随机的方式分散,平均周转率为89%,并随红树植物群落周转而呈线性增加,主要受pH和白骨壤(Avicennia marina)周转的影响。研究揭示了大型底栖动物与植物群落和环境之间的关系,为城市化背景下红树林生态系统的保护和恢复提供基础资料。  相似文献   

5.
Although combining datasets is often needed to unravel large-scale or long-term patterns in benthos ecology, this is frequently hampered by differences in technical design of the individual studies. One element that often vary among macrobenthic studies is the sieving procedure: sieving alive versus sieving after fixation. This study therefore aimed at the qualification and quantification of the impact of sieving procedure, using a 1 mm mesh sized sieve, at three levels of ecological organisation: (1) diversity, (2) species and taxon density, and (3) community structure. To include a maximum suite of macrobenthic species and to evaluate the community-specific effects, the impact of sieving procedure was investigated within four widely spread macrobenthos communities in the Belgian part of the North Sea. Sieving alive negatively impacted all tested diversity measures (S, N1, N2, N, H′, ES 100 and J′): community-dependent relative losses of up to 35% were observed. However, most trends were ambiguous and statistically non-significant. Community- and taxon-dependent impacts were detected at the level of density. Mainly polychaetes were found to be negatively impacted by sieving alive (relative losses maximum 81%): especially small, interstitial polychaetes (e.g. Hesionura elongata and Spio filicornis) tend to actively escape from the sieve (relative loss up to 100%). Next to size, also behaviour, the presence of head appendages, the depth of the sampling stations and sampling season are believed to influence the sieving procedure impact. While detailed community composition was impacted (ANOSIM dissimilarity: maximum 85%), no major impact on the differentiation between the investigated communities was detected. The present study thus demonstrated that combining data, retrieved with a different sieving procedure can be useful, but its reliability will mainly depend on the type of questions one wants to answer. In all cases caution at all levels of ecological organisation is advised.  相似文献   

6.
《农业工程》2022,42(6):670-678
The research objective was to describe the distribution of phytoplankton community structure and corelated to the physic-chemical parameters at fishing ground, Banyuasin estuarine waters. The methodology of research was phytoplankton sampling; physicochemical waters parameters data collected such as; dissolved oxygen, pH, temperature, brightness, salinity, current speed, nitrate, and phosphate. Identifications and calculations phytoplankton are based on photography under a light microscope. Data were analyzed by calculated abundance, diversity (H′ index) and dominance (C index), and Principal Component Analysis (PCA). There were 24 species of phytoplankton on the all-observation station grouped in three classes, Bacillariophyceae 91.3%, Dinophyceae 9%, and Cyanophyceae 0.1%. The abundance of phytoplankton species obtained in the range of 666.48 to 184,592.68 cells L?1, were mostly found in high Chaetoceros affinis and Bacteriastrum furcatum. The distribution of phytoplankton abundance in these waters was found to be more influenced by seawater mass than freshwater. Phytoplankton diversity is considered a moderate category (1.37 < H′ < 2.57), and there were no species of phytoplankton that dominates (C < 0.5). Principal component analyzes showed that waters can be classified based on their physical-chemical characteristics, which were temperature, salinity, pH, transparency, current speed in the south coast around river estuaries, while DO and nutrients on the north coast of the waters. Based on the distribution of phytoplankton abundance is illustrated that the northern part is more potential for fishing area than the southern part with an abundance of phytoplankton >90,000 cells L?1 and more stable water dynamics.  相似文献   

7.
Ceratocystis wilt disease has caused significant mortality in duku (Lansium domesticum) since 2014 and has now spread to all districts in South Sumatra, Indonesia. Recently, 16 isolates from duku representing populations from various districts in South Sumatra were isolated. Analysis for the morphological characteristic of the isolate showed that the population has a uniform morphology. Genetic analysis based on internal transcribed spacer (ITS) and β-tubulin sequences verified that the population has being dominated by the ITS5 haplotype of Ceratocystis fimbriata and a new ITS group, the ITS7b haplotype that was localized in Musi Banyuasin. Both haplotypes were highly pathogenic to duku. Inoculation tests on various forest and agroforestry plant hosts showed that both haplotypes were highly pathogenic to Acacia mangium, moderately pathogenic to Acacia carsicarpa, Eucalyptus urophylla, and Melaleuca cajuputi, but weakly pathogenic to Dyera costulata, Hevea brasiliensis, and Alstonia scholaris. Therefore, this pathogen becomes a serious threat to Indonesia’s biodiversity due to its ability to infect forest and agroforestry plants, especially the indigenous ones.  相似文献   

8.
南沙群岛珊瑚礁浮游动物多样性与群落结构   总被引:3,自引:0,他引:3  
珊瑚礁是地球上已知的海洋生物多样性最高的生态系统,为了深入分析珊瑚礁的浮游动物多样性和群落结构,2004年5月5-15日在南沙群岛渚碧礁布设10个大面站(漏湖、礁坪各5个)和1个连续站(位于礁坪),使用网目孔径分别为169 μm和505 μm的两种浮游生物网进行垂直拖网采样.结果表明:共鉴定浮游动物种类96种和幼虫17个类群(或类型),其中桡足类最多,达65种,其次是幼虫;浮游动物数量丰富-根据169 μm网具样品的数据,平均丰度高达926.0±1,155.8 inds./m3,优势类群依次是桡足类、被囊类和幼虫,优势种为奥氏胸刺水蚤(Centropages orsinii)、珍妮纺锤水蚤(Acartia shuzheni)、长尾住囊虫(Oikopleura longicauda)、梭形住囊虫(O.fusifornis)和腹足类面盘幼虫(Gastropoda veliger);渚碧礁浮游动物空间分布差异相当显著,漏湖区形成与礁坪区不同的群落,前者种类多、丰度高、优势种突出、均匀度低,而后者则完全相反,浮游动物群落的空间变化是由珊瑚礁礁盘的空间异质性所造成.浮游动物昼夜变化明显,夜间出现的种数和平均丰度分别是日间的4.6和46.2倍.浮游动物群落以终生浮游生物的种类和数量占多数,它们来源于礁外海水,有的也属于礁栖类型.在珊瑚礁中,中小型浮游动物无论在种类还是丰度方面都占有非常重要的位置.  相似文献   

9.
Collections of arboreal Psocoptera from the four major national parks of Sumatra and from a range of habitats outside the parks (including many of the predominant perennial crops) are appraised for diversity and species overlap between habitats. The most speciose family (Psocidae, 72 morphospecies) is investigated to determine possible surrogacy values in relation to the more taxonomically intractable Other Psocoptera (17 families, 190 morphospecies), in its incidence in 16 different habitats and four main altitudinal zones. Considerable psocid richness persists in disturbed areas, and the values of protected areas and kebun gardening systems in their conservation are noted.  相似文献   

10.
The rapid conversion of Southeast Asian lowland rainforests into monocultures calls for the development of rapid methods for species identification to support ecological research and sustainable land‐use management. Here, we investigated the utilization of DNA barcodes for identifying flowering plants from Sumatra, Indonesia. A total of 1,207 matK barcodes (441 species) and 2,376 rbcL barcodes (750 species) were successfully generated. The barcode effectiveness is assessed using four approaches: (a) comparison between morphological and molecular identification results, (b) best‐close match analysis with TaxonDNA, (c) barcoding gap analysis, and (d) formation of monophyletic groups. Results show that rbcL has a much higher level of sequence recoverability than matK (95% and 66%). The comparison between morphological and molecular identifications revealed that matK and rbcL worked best assigning a plant specimen to the genus level. Estimates of identification success using best‐close match analysis showed that >70% of the investigated species were correctly identified when using single barcode. The use of two‐loci barcodes was able to increase the identification success up to 80%. The barcoding gap analysis revealed that neither matK nor rbcL succeeded to create a clear gap between the intraspecific and interspecific divergences. However, these two barcodes were able to discriminate at least 70% of the species from each other. Fifteen genera and twenty‐one species were found to be nonmonophyletic with both markers. The two‐loci barcodes were sufficient to reconstruct evolutionary relationships among the plant taxa in the study area that are congruent with the broadly accepted APG III phylogeny.  相似文献   

11.
SUMMARY. 1. Patterns of co-occurrence of benthic macroinvertebrates across different habitat patches were monitored for 1 year at one site on the Acheron River, Victoria.
2. There was a gradual transition in community structure between erosional and depositional habitat extremes. The correspondence between faunally defined sample groups and habitats was not exact.
3. Seasonal changes in community pattern were demonstrated only for erosional habitats. Again the transition was gradual rather than abrupt and contrasted sharply with data from more severe hydrological regimes.
4. Most of the community pattern was conferred by a minority of the species present. These species generally had special requirements that apparently could be satisfied only by being confined to the surface layer of sediments.  相似文献   

12.
We explored the genetic diversity and structure of the striped snakehead (Channa striata) across Malaysia and Sumatra (Indonesia) using the partial mtDNA CO1 gene. Twenty five populations (n = 345) were assayed and subdivided into six regions, following the physiogeographical barriers. Populations Sega (SG), Tanjung Tambutan (TR), Kajang (KJ) and Linggi (LG) are highly diversified (Hd: 0.484–0.762, π: 0.0033–0.0059) which could serve as candidates for a selective breeding programme. The only population that contributed to the total allelic richness is Takengon (CS) as it is highly differentiated from other populations and genetically variable within population. We detected two major phylogenies: 1) northwest Peninsular Malaysia and 2) all other regions of Malaysia and Sumatra, Indonesia. They are products of the physical restriction to gene flow between the two lineages by the Bintang Mountain Range. A total of 92.4% of the population pairwise comparison FST showed significant structuring, yet several geographically distant populations showed a close genetic relationship. The discrepancy is due to ancient population dispersal and human-mediated translocation. These major findings provide an important base study for initiating a selective breeding program. The high population genetic diversity requires independent conservation as they contain most of the total diversity in this area.  相似文献   

13.
Abstract. 1. Seventeen species of phytophagous arthropods (sixteen insects and one gall-forming eryiophyid mite) were found feeding on the above-ground parts of bracken ( Pteridium aquilinum (L.) Khun.) in surveys throughout the geographic range of the plant in South Africa. A further thirteen species of insects may possibly feed on the plant in this region.
2. Given the area over which bracken grows in South Africa, this is very close to the number of species expected on the plant, based on species-area calculations and comparisons with bracken in other geographic regions.
3. The species-richness of bracken-feeding arthropods in local communities reflects the size of the regional pool of species in different geographic areas. Local richness in South Africa is intermediate between that in south-western U.S.A. and Britain.
4. In both Britain and South Africa there is a weak tendency (0.05 < P < 0.07) for larger local patches of bracken to support more species of phytophages than small patches, with similar very shallow slopes (0.083 and 0.086) in plots of log species versus log area on both continents.
5. The taxonomic composition of bracken-feeding arthropods in South Africa is markedly different from that in other pants of the world, suggesting very different and largely independent evolutionary histories in different regions.
6. There is no sign of convergence in the feeding niches of communities of bracken-feeding arthropods in different parts of the world, and the pattern of feeding relationships is very different in South Africa to patterns observed elsewhere. Conspicuous vacant niches (ways of exploiting the plant that are observed in other geographic regions) are easily identified in the South African communities.  相似文献   

14.
围垦对长江口南岸底栖动物群落结构及多样性的影响   总被引:45,自引:3,他引:45  
袁兴中  陆健健 《生态学报》2001,21(10):1642-1647
通过对长江口南岸围垦潮滩和自然潮滩大型底栖无脊椎动物进行取样调查,研究了围垦潮滩的底栖动物群落结构及其多样性特性,分析了围垦对潮滩底栖动物群落结构及多样性的影响,研究发现,(1)围垦氏栖动物群落种类减少,种类组成发生变化;总趋势是,围垦以后,甲壳动物种类明显减少,由7种减少到1种;随着围垦时间延长,多毛类种类减少,由4种减少到3种,直到最后消失,而软体动物和昆虫幼虫种类所占比例则明显增加,分别从占总种数的29.41%,5.89%增加到50.00%和25.00%;(2)围垦1a且仍受潮水影响的潮滩,底栖动物种类丰度虽有降低,但其密度和生物量却明显增加,分别从132.10个/m^2,35.31g/m^2(湿重)增加到218.32个/m/ 2和79.66g/m^2(湿重),围垦2a且潮水不能进入的潮滩,底栖动物生物量大大降低,降到3.02g/m^2(湿重);(3)围垦时间短且仍受潮水影响的潮滩与未围垦的自然潮滩相比,其底栖动物多样性降低不明显,围垦时间长且潮水不能进入的潮滩,底栖动物多样性明显降低,反映了围垦导致潮滩湿地生境退化;(4)围垦对底栖动物群落结构及多样性的影响,是通过改变潮滩湿地生境中的多种环境因子造成的,如潮滩高保,水,动力,沉积物特性,植被演替等,是各种因子综合作用的结果。  相似文献   

15.
乐清湾滩涂大型底栖动物群落结构的时空变化   总被引:1,自引:0,他引:1  
由滨海湿地独特的地理位置和特殊的作用,国内一些专家对一些重要的河口和沿海潮间带底栖动物生态学进行了研究,如长江口(袁兴中、陆健健,2001a,b)、深圳湾(厉红梅等,2001;厉红梅、孟海涛,2004)、胶州湾(李新正等,2006)、杭洲湾(范明生等,1996)以及其它滨海湿地(张永普等,2001;鲍毅新等,2006).  相似文献   

16.
【目的】了解江苏省徐州市云龙湖大型底栖动物的群落结构及其环境影响因子,可以为保护云龙湖水生态环境提供依据。【方法】于2013—2017年对云龙湖大型底栖动物和水环境因子进行了调查。利用1/16 m2彼得逊采泥器采集大型底栖动物样品,同时利用有机玻璃采水器采集水样,每年的5月和10月各采样一次,共采样10次。利用3种群落多样性指数(Shannon-Wiener指数、Margalef物种丰富度指数、Pielou均匀度指数)评价云龙湖大型底栖动物的群落结构,选择ShannonWiener指数进行水质评价,并应用典型相关分析(CCA)得出大型底栖动物与环境因子之间的关系。【结果】云龙湖大型底栖动物群落结构简单,物种较少,3种群落多样性指数年际波动不大。云龙湖水质多年处于轻污染到中污染水平之间。优势物种中水丝蚓属的主要影响因子是总氮浓度,摇蚊幼虫的主要影响因子为高锰酸盐指数。【结论】云龙湖的水体有富营养化风险,应对云龙湖大型底栖动物的保护和水质改善给予足够重视。  相似文献   

17.
Agroecology and conservation must overlap to protect biodiversity and farmer livelihoods. Coffee agroecosystems with complex shade canopies protect biodiversity. Yet, few have examined biodiversity in coffee agroecosystems in Asia relative to the Americas and many question whether coffee agroecosystems can play a similar role for conservation. We examined vegetation, ant and bird diversity, coffee yields and revenues, and harvest of alternative products in coffee farms and forests in SW Sumatra, Indonesia near Bukit Barisan Selatan National Park (BBS). BBS is among the last habitats for large mammals in Sumatra and >15,000 families illegally cultivate coffee inside of BBS. As a basis for informing management recommendations, we compared the conservation potential and economic outputs from farms inside and outside of BBS. Forests had higher canopy cover, canopy depth, tree height, epiphyte loads, and more emergent trees than coffee farms. Coffee farms inside BBS had more epiphytes and trees and fewer coffee plants than farms outside BBS. Tree, ant, and bird richness was significantly greater in forests than in coffee farms, and richness did not differ in coffee farms inside and outside of BBS. Species similarity of forest and coffee trees, ants, and birds was generally low (<50%). Surprisingly, farms inside the park were significantly older, but farm size, coffee yields, and revenues from coffee did not depend on farm location. Farmers outside BBS received higher prices for their coffee and also more often produced other crops in their coffee fields such that incentives could be created to draw illegal farmers out of the park. We also discuss these results with reference to similar work in Chiapas, Mexico to compare the relative contribution of coffee fields to conservation in the two continents, and discuss implications for working with farmers in Sumatra towards conservation plans incorporating sustainable coffee production.  相似文献   

18.
19.
濒危植物四合木(Tetraena mongolica)为我国特有的蒺藜科单种属落叶小灌木.对四合木林地昆虫群落进行了调查,共得昆虫标本11363号,263种.隶属于67个科(或总科)11个目.同翅目的个体数量和优势度指数最高;膜翅目的物种丰富度和多样性指数最大;双翅目的均匀度最大.数量优势类群(>10%)为木虱和叶蝉类,常见类群(1%~10%)是象甲、小蜂、粒脉蜡蝉、拟步甲、蚂蚁、蝽科、皮蝽、盲蝽、斑翅蝗科昆虫.营养结构中植食性类群在种类和数量上占绝对优势,其中的吸食类昆虫优势度最大;天敌昆虫以寄生性类群为主,多样性最高;捕食性和中性昆虫的种类和数量相对较少,但捕食者的均匀度最高.灌木层与草本层相比,灌木层昆虫群落的物种丰富度和个体数量明显占优;优势种的优势度大.而草本层昆虫群落的多样性和均匀度高.2层整体的相似性低.膜翅目的共有种最多.  相似文献   

20.
Biological diversity and the complexity of the community structure of benthic animals in different bodies of water are evaluated using the Shannon index. The literature data on the communities in Lake Krasnoye (Karelian Isthmus, Leningrad Oblast), Shchuchy Bay of Lake Ladoga, Neva Bay, and the eastern part of the Gulf of Finland have been analyzed. The extrema (maxima and minima) and the inflection point of the curve of functions are determined with the help of derivatives. The rate of the secondary succession is evaluated for the first time by the example of benthic communities. It is shown that the community structure of bottom animals in the Shchuchy Bay ecosystem formed in the process of succession proves to be more complex than in Lake Krasnoye and the Neva Bay communities that have been formed for a long time. Communities of bottom animals are less complex in polluted waters of the top of the eastern part of the Gulf of Finland. It has taken 12 years to reach the maximum diversity of the bottom animal communities in Shchuchy Bay, 16 years in Lake Krasnoye, and 7–10 years in Neva Bay. It is supposed that, under favorable conditions in the waterbodies of a moderate climate and in the absence of heavy pollution or eutrophication, it takes 12–14 years on average to form the most complex community structure of bottom animals (3–4 bit/spec.). The structure of communities in polluted waters remains simple.  相似文献   

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