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1.
为了解广西生态茶园与普通茶园节肢动物群落结构特点及其稳定性,本文采用Shannon-Wiener多样性指数(H′)、群落物种优势度指数(D)、丰富度指数(J)、物种均匀度指数(E)等分析了茶园节肢动物群落的多样性结构,应用群落相似度指数对生态茶园和普通茶园节肢动物的群落相似性进行了分析,用灰色关联度方法综合分析多样性指数与优势度、均匀度等6个特征参数间关系的密切程度。结果表明,在广西茶园节肢动物共34种,其中害虫(螨)17种,优势种群是:小贯小绿叶蝉Empoasca onukii Matsuda、茶蓟马Scirtothrips dorsalis Hood、蚜虫、白粉虱Trialeurodes vaporariorum Westwood;天敌8种,优势种群是:棕管巢蛛Clubiona japonicola Boeset Str.、八斑球腹蛛Theridion octomaculatum Boes. et Str.、异色瓢虫Harmonia axyridis(Pallas);中性昆虫9种,优势种群是:蚊虫、蚁类。多样性指数、群落均匀度指数与物种优势度在生态茶园比普通茶园高。生态茶园的群落稳定性比普通茶园的强。不同茶园间的群落相似性指数q在0.444~0.9355之间,群落间相似性关系在中等不相似与极度相似之间。与多样性指数密切相关的前3位群落特征参数依次是群落物种优势度、益害物种的个体数比、丰富度,其中关系最密切的特征参数是群落物种优势度。研究结果为茶园害虫的综合防控提供了理论依据。  相似文献   

2.
珊瑚藻类对南麂列岛潮间带底栖生物群落多样性的影响   总被引:3,自引:0,他引:3  
为了解南麂列岛潮间带珊瑚藻类对于其他大型藻类和底栖动物的影响,在南麂列岛国家级海洋自然保护区布设了4条潮间带断面,于2012年5月至2013年2月对其生物状况进行了逐季调查,分别分析了中低潮区大型藻类、非珊瑚藻大型藻类、底栖动物的物种多样性和均匀度,并计算了大型底栖动物的功能多样性指数Rao's Q。主要结果如下:(1)共采集和鉴定出大型藻类52种,其中珊瑚藻科藻类有5种;(2)珊瑚藻类在高潮区没有分布,在中低潮区均占据优势,占潮间带藻类生物量的68.9%。四季中低潮区大型藻类的Shannon-Wiener多样性指数范围为1.638–4.044,非珊瑚藻大型藻类的多样性指数范围为1.495–3.809,底栖动物为5.289–6.917;大型藻类的Pielou均匀度指数范围为0.819–0.971,非珊瑚藻大型藻类的均匀度指数范围为0.830–0.973,底栖动物为0.967–0.988;(3)大型藻类物种多样性和均匀度指数的降低与珊瑚藻类优势度的增加相关,但珊瑚藻类优势度与底栖动物物种多样性指数、均匀度指数和功能多样性指数均没有显著相关性;(4)底栖动物功能多样性与珊瑚藻类优势度均呈低潮区高于中潮区的变化规律,但相关性分析表明两者间并无直接联系。推测珊瑚藻类通过竞争占据了其他藻类的生存空间,从而降低了南麂列岛潮间带大型藻类的物种多样性和均匀度。底栖动物则因其自身生活特点而使得珊瑚藻类的扩张未能影响其多样性水平。  相似文献   

3.
嵊泗海岛不同底质潮间带春秋季大型底栖动物的群落格局   总被引:9,自引:0,他引:9  
于2006年9月(秋季)和2007年4月(春季)对嵊泗海岛的不同底质潮间带断面设立的8个取样站采集的调查资料,采用ABC曲线方法和大型多元统计分析软件PRIMER5对嵊泗海岛大型底栖动物进行Bray-Curtis相似性聚类分析和非度量MDS标序,研究群落结构格局以及用物种多样性指数、物种均匀度和物种丰富度指数分析潮间带大型底栖动物物种多样性和群落种类组成,并对大型底栖动物的群落结构进行了初步研究。调查获得嵊泗海岛的不同底质潮间带大型底栖动物130种,其中多毛类31种,软体动物57种,节肢动物32种,棘皮动物4种,其它类6种。春、秋季嵊泗潮间带大型底栖动物多样性指数(H′)(F1,13=0.10,P=0.75)、物种丰富度(D)(F1,13=0.66,P=0.43)和均匀度指数(J)(F1,13=0.33,P=0.58)均无显著差异;不同底质嵊泗潮间带大型底栖动物多样性指数(H′)(F1,13=14.28,P<0.01)、物种丰富度(D)(F1,13=14.07,P<0.01)存在显著差异,而均匀度指数(J)(F1,13=1.62,P=0.23)无显著差异。群落结构聚类分析和MDS标序表明,8个取样站的群落可分为3组(Ⅰ、Ⅱ和Ⅲ组)。根据所调查嵊泗海岛潮间带的丰度和生物量资料做的ABC曲线分析表明,底栖动物群落受到了中等程度的污染或者扰动。  相似文献   

4.
中国沙拐枣属天然群落特征及其物种多样性研究   总被引:4,自引:1,他引:3  
根据野外调查资料,应用生物多样性的原理和方法计测了群落的物种丰富度指数(R0、R1)、物种多样性指数(H′、D)、均匀度指数(E)以及优势度指数(C)以分析中国沙拐枣属天然群落的群落学特征。结果表明(1)中国沙拐枣属天然群落组成成分简单,共出现种子植物91种,分属22科62属,科属组成较为分散;生活型组成中1年生植物种类多,数量大,占总数的35.16%;沙拐枣属天然群落的垂直结构明显;(2)多样性分析表明,中国沙拐枣属天然群落物种组成单一,结构简单,其中群落多样性最低分别为塔克拉玛干沙拐枣(Calligonum roborowskii)群落和沙拐枣(C.mongolicum)(若羌)群落。群落多样性最高分别为沙拐枣(C.mongolicum)(采南)群落、小沙拐枣(C.pumilum)群落和艾比湖沙拐枣(C.ebi-nuzicum)群落。不同沙拐枣属植物所形成的群落差异主要表现在物种组成以及物种多样性水平,这种差异表现主要是1年生和多年生草本植物的物种多样性。(3)丰富度指数和物种多样性指数表现出基本一致的变化趋势,而生态优势度指数则表现相反的趋势。物种的丰富度指数和多样性指数与群落的结构以及立地环境条件等有密切的关系,结构复杂的群落较其它群落的多样性指数高,但由于特殊生境所形成的单优群落物种多样性指数则较低。  相似文献   

5.
浙江天台山甜槠群落物种类多样性研究   总被引:7,自引:0,他引:7  
对浙江省天台山甜槠群落的不同样地、不同层次的物种丰富度、物种多样性指数和群落均匀度进行了分析。结果表明:木本植物的物种丰富度、物种多样性指数明显大于草本植物;而群落均匀度两者无显著差异。在群落垂直结构中,乔木层第二亚层的物种丰富度、物种多样性指数均显著大于第一亚层,它们之间的群落均匀度差异不显著。灌木层的牧种丰富度、多样性指数最大,乔木层次之,草木层最小。灌木层的群落均匀度明显大于乔木层,而乔木层  相似文献   

6.
采用ISSR分子标记对分布于山东省长岛县南部的北长山、南长山、大黑山和小黑山4个岛屿上的藜天然种群共81个个体进行了遗传多样性及遗传结构的研究。13个引物共检测到157个可重复的位点。遗传多样性研究结果表明:种内的多态位点比率为66.24%,具有较高的遗传多样性(Shannon(I)指数在物种水平上为0.332 0);种群间有一定的遗传分化,根据Gst值,种群间的遗传多样性占总群体的9.27%。遗传距离分析表明,XHS种群和NCS种群的遗传一致度最高,与地理距离无相关性。  相似文献   

7.
浙江仙居俞坑森林群落物种多样性研究   总被引:4,自引:0,他引:4  
分别采用物种丰富度、物种多样性指数和群落均匀度指标对浙江省仙居县俞坑森林群落的物种多样性进行测定和分析。结果表明:本木植物的物种多样性以生境优越的常绿阔叶林为高,木本植物的物种丰富度、物种多样性指数明显大于草本植物。在群落垂直结构中,木本植物等2层的物种丰富度、物种多样性指数均显著大于第1层。物种丰富度以木本第3层最大,草本层最小;而物种多样性指数、群落均匀度则以木本第2层最大、草本层最小。木本植物各层次、草本层的物种多样性各项指标在群落各样地间均有一定的差异。  相似文献   

8.
千岛湖岛屿小型兽类群落的多样性   总被引:3,自引:1,他引:2  
2007年秋季和2008年春季,选取千岛湖地区14个岛屿和2个半岛作为样地,采用夹夜法进行小型兽类群落组成调查.两季度共布夹20 400个,捕获小型兽类1 141只,隶属2目3科9属13种,啮齿目(Rodentia)鼠科(Muridae)10种和仓鼠科(Cricetidae)1种,食虫目(Insectivora)鼩鼱科(Soricidae)2种.利用以上结果分析其群落多样性,结果显示:14个岛屿小型兽类群落春、秋两季的多样性指数、均匀度指数和优势度指数均呈现极显著差异且优势种发生变化;对可能影响岛屿小型兽类群落多样性的岛屿面积、距最近陆地距离、距最近大岛距离和植物丰富度等因素进行逐步回归分析,发现只有植物丰富度对小型兽类群落的物种丰富度有显著影响;对16个样地按照物种组成比进行聚类,许源半岛样地与14个岛屿聚为一类,姚家半岛样地单独归为一类,相似性指数比较结果亦显示姚家半岛样地与其它样地的相似性指数偏低.结论:景观破碎化导致千岛湖岛屿小型兽类群落的稳定性下降,物种多样性季节变化强烈;随岛屿面积的增加,小型兽类物种丰富度并非总是增加的,而是出现反复,呈现明显的小岛效应;14个岛屿的物种与许源半岛样地物种构成比接近,推断在水库未形成前属同一生境.  相似文献   

9.
浙南岛屿岩相潮间带石鳖的群落结构   总被引:4,自引:1,他引:4  
研究了浙南岛屿岩相潮间带石鳖的群落结构。用Shannon-Wiener多样性指数(H′)、Pielous种类均匀度(J)、Margalef种类丰度(d)、Berger-Parker优势度指数(I)4个测定群落种类多样性指标进行数值分析,结果表明,水平变化,H′值为北麂的关帝山最大、七星岛最小,J值为洞头的鸽尾礁最大、七星岛最小,d值为南麂的马祖岙口和北麂的海利相对较大、北麂的筲箕屿最小,I值为七星岛最大、洞头的鸽尾礁最小;垂直变化,潮区由高到低,H′、J和d值呈逐渐增大的趋势,I值中潮区开始则逐渐变小;季节变化,H′、J、d值为春季>夏季>秋季>冬季,I值则相反。用Bray-Curtis群落相似性系数聚类分析,浙南岛屿潮间带石鳖群落可聚为两大类型。温度、潮汐、海岸开敞度、浪击度和空间异质性是影响石鳖群落结构的主要因素。  相似文献   

10.
澳门青洲山翻白叶树群落特征及物种多样性研究   总被引:3,自引:0,他引:3  
根据样方调查结果,对澳门青洲山翻白叶树(Pterospermum heterophyllum)群落的种类组成、外貌、结构特征与动态及物种多样性进行分析.结果表明:(1)在1 600 m2样地中,有维管束植物47种,隶属于29科44属;对乔木层和灌木层主要物种的重要值以及频度分析结果显示,该群落是以翻白叶树为主的单优种群落,群落种类组成多样性和水平分布不均匀,其外貌终年常绿;对优势种种群的年龄结构分析显示,该种群处于增长状态;(2)整个群落的物种丰富度Margalef指数为13.72,Shannon-Wiener指数为1.15,Simpson指数为0.875,均匀度指数为0.34,该群落的层次格局为:灌木层>藤本层>乔木层>草本层;(3) 与其他5个不同类型地区森林群的物种多样性比较结果显示,澳门翻白叶树群落的物种多样性明显低于其他5个森林群落.  相似文献   

11.
于2006年9月和2007年7月在中街山列岛4个有居民海岛岩相潮间带设立8个断面,对大型底栖动物的群落结构进行了调查.共获得大型底栖动物34种,其中腔肠动物1种,环节动物3种,甲壳动物10种,软体动物20种.优势种有日本笠藤壶(Tetraclita japonica)、紫贻贝(Mytilus edulis)和节蝾螺(Turb articulatus)等4种.以季节和站位为因子对多样性指数进行双因素方差分析,结果表明只有夏、秋季丰富度指数(P=0.028)存在显著差异,其他指数的方差分析没有显著差异(P>0.05).3个潮带4个岛屿共12个站位的聚类分析和MDS标序分析表明,12个群落可分为3组(Ⅰ、Ⅱ和Ⅲ组).大型底栖动物ABC曲线分析表明底栖动物群落尚未受到干扰.  相似文献   

12.
Studies on the implications of food web interactions to community structure have often focused on density-mediated interactions between predators and their prey. This approach emphasizes the importance of predator regulation of prey density via consumption (i.e. lethal effects), which, in turn, leads to cascading effects on the prey's resources. A more recent and contrasting view emphasizes the importance of non-lethal predator effects on prey traits (e.g. behaviour, morphology), or trait-mediated interactions. On rocky intertidal shores in New England, green crab ( Carcinus maenas ) predation is thought to be important to patterns of algal abundance and diversity by regulating the density of herbivorous snails ( Littorina littorea ). We found, however, that risk cues from green crabs can dramatically suppress snail grazing, with large effects on fucoid algal communities. Our results suggest that predator-induced changes in prey behaviour may be an important and under-appreciated component of food web interactions and community dynamics on rocky intertidal shores.  相似文献   

13.
Many theories of consumer control of communities have come from studies conducted in relatively benign, temperate zone rocky intertidal systems. Here, we examine gastropod grazing and the maintenance of bare space on a dry, wind-swept rocky shore of Patagonia, Argentina. Two limpet species are the primary intertidal grazers. Siphonaria lessoni dominates mid and high intertidal zones, while Nacella magellanica dominates the lower zone. In all zones, limpet densities are positively correlated with bare space and the occurrence of cracks. Tethering experiments revealed that: (1) physical stress sets the upper distribution limit of both limpets, (2) predators, such as oyster catchers, regulate Nacella populations and may restrict them to cracks and vertical surfaces, and (3) desiccation stress appears to drive similar crack distribution patterns of Siphonaria in the upper intertidal. Experimental removal of limpets in each intertidal zone indicated that limpets have: (1) no detectable effect in the high intertidal where physical forces dominate community organization, (2) weak impacts at mid-elevations as grazing only limited the abundance of fleshy algae with physical forces again dominating community structure, and (3) relatively stronger, but still weak impacts in the low zone. These results suggest that grazing impacts on Argentine rocky shores are weak in comparison to the physical stresses (e.g. high winds, low humidity) that largely determine structure in this system. The dominance of physical forcing in this system occurs despite having similar grazer densities to other temperate, but comparatively wet, rocky shorelines (e.g. British Isles) where top-down control is strong.  相似文献   

14.
The decline or loss of habitat-forming species has affected rocky shore marine communities worldwide. Many short-term studies have documented the initiation of cascading effects due to canopy losses of macroalgae, but relatively few studies have followed recovery dynamics over many years. Here, we show that the experimental removal of a dominant intertidal fucoid in southern New Zealand had numerous community effects up to 8 years later. Even though the dominant fucoid returned to a nearly closed canopy, there remained many differences between disturbed and control communities. The disturbed treatments had lower plant density and biomass of the dominant fucoid, fewer species and more turfing coralline algae than controls. Plots with press disturbances were more affected than those with pulse disturbances. The negative feedback of turfing algae on the recovery of fucoid recruitment resulted in effects on cover and diversity in the wider community being evident after 8 years. We discuss the feedbacks between fucoids, benthic turfing algae and community recovery and argue that if biodiversity impacts on marine rocky reefs are to be understood, the role of non-trophic interactions in structure, function and dynamics must be better delineated.  相似文献   

15.
Summary Relationships between organisms at all trophic levels are influenced by the primary productivity of the ecosystem, and factors which enhance rates of primary production may modify trophic relationships and community structure. Nutrient enrichment of intertidal and nearshore waters leads to enhanced production by intertidal algae, and it was hypothesized that where rocky shores are washed by nutrient-rich upwelled waters, the intertidal communities should show a characteristic functional structure, based on the effects of enhanced primary production. Study sites were chosen on rocky shores in southern Africa, central Chile and the Canary Islands, in areas with and without coastal upwelling, and mid-shore community structure at these sites was analysed in terms of the abundance of certain functional guilds of organisms.It was found that algal cover and the biomass of herbivorous limpets supported per unit area on rocky shores were significantly greater in regions of coastal upwelling than in regions where upwelling did not occur. Ground cover by sessile filter-feeding organisms was significantly greater on shores in non-upwelled areas. However, correspondence analysis showed no functional aspect of intertidal community structure that was characteristic of coasts washed by upwelled waters. Primary reasons for this are probably the large variations in the nature of nutrient enrichment that accompanies upwelling, and in the nutrient status of non-upwelled areas. Other factors are man's exploitation of intertidal organisms and differences in the genetic origins of the intertidal species involved.  相似文献   

16.
Phylogeography and historical ecology of the North Atlantic intertidal   总被引:28,自引:0,他引:28  
Abstract Recent glaciation covered the full extent of rocky intertidal habitat along the coasts of New England and the Canadian Maritimes. To test whether this glaciation in fact caused wholesale extinction of obligate rocky intertidal invertebrates, and thus required a recolonization from Europe, we compared American and European populations using allelic diversity and techniques adapted from coalescent theory. Mitochondrial DNA sequences were collected from amphi-Atlantic populations of three cold-temperate obligate rocky intertidal species (a barnacle, Semibalanus balanoides , and two gastropods, Nucella lapillus and Littorina obtusata ) and three cold-temperate habitat generalist species (a seastar, Asterias rubens ; a mussel, Mytilus edulis , and an isopod, Idotea balthica ). For many of these species we were able to estimate the lineage-specific mutation rate based on trans-Arctic divergences between Pacific and Atlantic taxa. These data indicate that some obligate rocky intertidal taxa have colonized New England from European populations. However, the patterns of persistence in North America indicate that other life-history traits, including mechanisms of dispersal, may be more important for surviving dramatic environmental and climatic change.  相似文献   

17.
The ecological consequences of human‐driven overexploitation and loss of keystone consumers are still unclear. In intertidal rocky shores over the world, the decrease of keystone macrograzers has resulted in an increase in the dominance of herbivores with smaller body (i.e., “mesograzers”), which could potentially alter community assembly and structure. Here, we experimentally tested whether mesograzers affect the structure of rocky intertidal communities during the period of early colonization after the occurrence of a disturbance. A manipulative field experiment was conducted to exclude mesograzers (i.e., juvenile chitons, small snails, amphipods, and juvenile limpets) from experimental areas in an ecosystem characterized by the overexploitation of keystone macrograzers and predators. The results of multivariate analyses suggest that mesograzers had significant effects on intertidal community structure through negative and positive effects on species abundances. Mesograzers had negative effects on filamentous algae, but positive effects on opportunistic foliose algae and barnacles. Probably, mesograzers indirectly favored the colonization of barnacles and foliose algae by removing preemptive competitors, as previously shown for other meso‐ and macrograzer species. These results strongly support the idea that small herbivores exert a firm controlling effect on the assembly process of natural communities. Therefore, changes in functional roles of top‐down controllers might have significant implications for the structure of intertidal communities.  相似文献   

18.
We present a Markov chain model of succession in a rocky subtidal community based on a long-term (1986-1994) study of subtidal invertebrates (14 species) at Ammen Rock Pinnacle in the Gulf of Maine. The model describes successional processes (disturbance, colonization, species persistence, and replacement), the equilibrium (stationary) community, and the rate of convergence. We described successional dynamics by species turnover rates, recurrence times, and the entropy of the transition matrix. We used perturbation analysis to quantify the response of diversity to successional rates and species removals. The equilibrium community was dominated by an encrusting sponge (Hymedesmia) and a bryozoan (Crisia eburnea). The equilibrium structure explained 98% of the variance in observed species frequencies. Dominant species have low probabilities of disturbance and high rates of colonization and persistence. On average, species turn over every 3.4 years. Recurrence times varied among species (7-268 years); rare species had the longest recurrence times. The community converged to equilibrium quickly (9.5 years), as measured by Dobrushin's coefficient of ergodicity. The largest changes in evenness would result from removal of the dominant sponge Hymedesmia. Subdominant species appear to increase evenness by slowing the dominance of Hymedesmia. Comparison of the subtidal community with intertidal and coral reef communities revealed that disturbance rates are an order of magnitude higher in coral reef than in rocky intertidal and subtidal communities. Colonization rates and turnover times, however, are lowest and longest in coral reefs, highest and shortest in intertidal communities, and intermediate in subtidal communities.  相似文献   

19.
Lloyd W. Morrison 《Oecologia》1996,107(2):243-256
The ant species inhabiting three remote Polynesian islands were censused by hand collecting techniques. Three commonly occurring species, which exhibited complementary distribution patterns, were numerically and behaviorally dominant to other species in the communities in which they occurred. Field observations and laboratory experiments showed that negative interspecific interactions were important in maintaining the exclusive territories of the dominant species. Habitat also played a role in determining the distribution of dominant species. Pairwise tests of association among all species revealed dominant species were commonly positively associated with their own non-overlapping group of subordinate species, forming a large-scale mosaic distribution pattern of dominant and subordinate species. Baiting experiments, conducted with and without the dominant species removed, demonstrated that the presence of the dominant species decreased: (1) the proportion of baits occupied by other species, and (2) overall ant species diversity, at rich food resources. In ant communities where one of the three recognized dominant species was present, the outcome of negative interspecific interactions among species was more predictable than in communities without a recognized dominant. The same patterns were evident regardless of which of the three dominant species was present in the community. These patterns of community organization observed in this relatively newly assembled fauna are very similar to those reported from studies of older ant communities in mainland areas.  相似文献   

20.
The urgency to find efficient indices and indicators to prevent further deterioration of coastal areas is one of the hot topics in today’s scientific publication. However, a detailed knowledge of community responses to anthropogenic impacts is essential to sustain those indices. The studies on the response of benthic community to sewage pollution on intertidal rocky shores are generally based on visual census and do not take into account the tidal levels. In order to fulfil this gap in this study: (i) the sampling was performed by destructive sampling, with all individuals identified to the species level; (ii) the sampling was done at all levels of the intertidal (sublittoral fringe, eulittoral, and littoral fringe). Sewage pollution changed the environmental variables and the abundance of macroinvertebrates, being Mytilus galloprovincialis, Melarhaphe neritoides, and Chthamalus montagui the species most responsible for the dissimilarities observed. Effects were different on the three intertidal zones: community structure changed in the sublittoral fringe; suspension-feeders abundances and species richness increased in the eulittoral; no differences were detected in the littoral fringe. Moreover, the results confirm that the presence of sewage discharges tended to benefit suspension feeders, and that the sensitive species were replaced by opportunistic ones.  相似文献   

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