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21.
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
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Global fire regimes are shifting due to climate and land use changes. Understanding the responses of belowground communities to fire is key to predicting changes in the ecosystem processes they regulate. We conducted a comprehensive meta‐analysis of 1634 observations from 131 empirical studies to investigate the effect of fire on soil microorganisms and mesofauna. Fire had a strong negative effect on soil biota biomass, abundance, richness, evenness, and diversity. Fire reduced microorganism biomass and abundance by up to 96%. Bacteria were more resistant to fire than fungi. Fire reduced nematode abundance by 88% but had no significant effect on soil arthropods. Fire reduced richness, evenness and diversity of soil microorganisms and mesofauna by up to 99%. We found little evidence of temporal trends towards recovery within 10 years post‐disturbance suggesting little resilience of the soil community to fire. Interactions between biome, fire type, and depth explained few of these negative trends. Future research at the intersection of fire ecology and soil biology should aim to integrate soil community structure with the ecosystem processes they mediate under changing global fire regimes. 相似文献
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长白山北坡土壤动物群落物种共有度的海拔梯度变化 总被引:17,自引:2,他引:17
群落间各生活型土壤动物科及所有土壤动物科的共有度,一定程度上反映了群落间的相关性及沿环境梯度的物种替代关系。应用梯度格局法在长白山北坡海拔550~2650m地段,每隔100m海拔高度设置一块样地,共计22块样地,并应用Jaccard指数,对各海拔不同土壤动物群落间物种共有度的海拔梯度变化进行了分析。结果表明,不同海拔土壤动物群落间物种的共有度,无论以哪一生活层的土壤动物科来表达,基本都以与其最相邻的群落间为最高,群落间物种共有度峰值与谷点反映了群落类型随海拔具有间断性变化。线虫、甲螨、弹尾等各生活型土壤动物的共有度以及所有土壤动物科的共有度,均随着海拔差的增加呈下降趋势,但并非与植被情况完全吻合。 相似文献
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H. L. G. STROYAN 《Zoological Journal of the Linnean Society》1979,65(1):1-54
Twenty-five species and two subpecies of aphids are listed and dicussed as additions to the Brutish fauna since publication of "Additions and amendment to the Cheack List British aphids" subspecies is described as new to sicence. 相似文献
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Alexandre P. Hercos Ana Carolina Prado-Valladares Jana M. del Favero Nagila A. Zuchi Túlio F. Teixeira Fábio E. A. Albuquerque Helder L. de Queiroz 《Zeitschrift fur angewandte Ichthyologie》2021,37(6):985-988
Length-weight relationships (LWRs) were estimated for 16 ornamental fish species from Amanã Lake and nine tributary streams, in Central Brazilian Amazonia. Sampling was carried out bimonthly for a year (2007–2008), using two sets of four gillnets (20 m × 2 m, 2,5; 3,5; 04; 4,5 cm stretch mesh size); trawls were performed with seine nets (35 m × 6 m, 3 mm stretch mesh size); native fish-traps (fyke-net like fish-traps woven from local lianas), and dip nets (0.5 m × 0.5 m stretch mesh size). Measurements were done for standard length (SL – 0.1 cm precision) and total weight (Wt – 0.01 g precision). This study provides information on the length–weight relationships for all sampled species and, in addition, provides new maximum standard lengths for six species. 相似文献
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Studies to determine mite species richness in natural environments are still scarce, and have been conducted mainly in tropical ecosystems. The aim of this study was to determine the species richness of mites on two common native plants in fragments of the semideciduous seasonal forest in the Northwest of São Paulo State, Brazil. In each of eight fragments, 10 specimens of Actinostemon communis (Euphorbiaceae) and 10 of Trichilia casaretti (Meliaceae) were selected and marked. In total, 124 species of mites belonging to 21 families were found on the two plants. Tarsonemidae had the highest diversity (34 species), followed by Phytoseiidae (31), Tetranychidae (9) and Tenuipalpidae (8). Species accumulation curves for the two sampled plants did not reach an asymptote, even with the large sampling effort. Hence, it is estimated that a greater sampling effort may lead to an increase in species richness compared with what was found in this study. The richness of this mite fauna suggests that preservation of these plant species is important to maintain the mite diversity in these forest fragments. 相似文献