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1.
M I Gordeev  V N Stegni? 《Genetika》1989,25(2):283-291
The role of chromosomal variability was studied in the process of biotopical distribution of larvae of the sibling species Anopheles messeae and A. beklemishevi. It is shown that frequency of the inversions XL1, XL2, 2R1, 3R1 of A. messeae was changed in the lakes with different larval quantity of the sibling species. Mosquito of A. beklemishevi were developed in the suboptimal biotops having low larwal quantity of A. messeae with the analogous chromosomal arrangement 2R1. The larvae with "northeast" genocomplexes of A. messeae prevailed over A. beklemishevi in the lakes with high larval quantity and this prevalence determined dominant state of A. messeae. It is noted that natural selection on the preimaginal stages of development acts in the direction of karyotypic divergence of the sibling species and promotes more effective utilisation of food resources by each species.  相似文献   

2.
李洁琼  宋晓阳  曹敏 《生态学杂志》2016,27(11):3403-3412
林下树种幼苗是森林生态系统的一个重要组成部分,在森林的自然更新过程中发挥着重要作用.为了解树种幼苗的海拔分布格局以及森林群落林下幼苗对季节性气候的响应,本研究调查了云南省哀牢山(亚热带)和玉龙雪山(亚高山)两个地区的林下树种幼苗物种组成及个体数量的海拔分布格局及其季节动态.结果表明:随着海拔的升高,两个山体的树种幼苗物种丰富度均先增加后下降,优势种也呈现明显的变化;雨季末期的幼苗物种丰富度明显大于旱季末期,其中,占据优势地位的物种具有较明显的季节性差异;不同海拔带树种幼苗优势种也具有显著差异.  相似文献   

3.
Inland Water Biology - The species composition and abundance of zoobenthos are studied to reveal the structure of bottom invertebrate communities under the effect of biotopical, hydrological, and...  相似文献   

4.
We made intensive samplings to study the seasonal response of spiders across different forest strata (ground and understory) in a tropical mountain cloud forest from Mexico. We sampled spiders from ten plots in six sampling events during the dry and rainy season, to analyze their abundance, structure (distribution of abundance among species), diversity and the response of the five dominant species at each stratum. Results demonstrated that seasonal patterns of spider communities differed among strata, revealing a complex spatiotemporal dynamic. Abundance, structure, diversity of ground spiders, as well as the responses of four dominant species at this stratum, showed low seasonal variations. In contrast, a strong seasonal variation was observed for the understory assemblage, with lowest abundance and highest diversity in the rainy season, and different assemblage structures for each season. Seasonal patterns of each assemblage seem linked to the responses of their dominant species. We found high co‐occurrence among most of the ground dominant species with similar habitat use and with multivoltine patterns, contrasting with low co‐occurrence among most of the understory dominant species with similar habitat use and univoltine patterns. Our results showed that the spiders’ assemblages of tropical mountain cloud forest (opposed to what is found in temperate and boreal forests) increase their species richness with the height, and that their responses to seasonal change differ between strata. Management programs of these habitats should consider the spatial and temporal variations found here, as a better understanding of their ecological dynamics is required to support their sustainable management.  相似文献   

5.
Data on the occurrence and adaptive potential of three mechanisms of cold-hardiness are analyzed in different taxa of soil invertebrates under the conditions of the cold climate of Northeast Asia. The relationship between low temperature resistance and overwintering conditions in selected species is discussed. It is shown that taxonomically close species may have different mechanisms and values of cold-hardiness. The effect of winter low temperature resistance on the biotopical distribution and formation of the soil invertebrate fauna in permafrost regions is assessed.  相似文献   

6.
The specific composition and number of midges in nest biotopes of birds of forest formations of Western Sikhote-Alin are given. 17 species of the genus Culicoides were found to attack 17 species of birds during the nesting period. The number of midges in nests depends both on the biotopical distribution of nests and mode of living of birds and on the total number of midges in nature. The most high percentage of females engorged with blood at nests was recorded in the obsoletus group, which is most abundant on man and at nests of birds of anthropogenic complex.  相似文献   

7.
Based on original data (450 samples from 115 streams of European Russia middle latitudes--from Pskov to Kostroma Regions) the attempt is made to describe the overall diversity of rheophilic communities dwelling on streams bottom and in macrophytes. In total, 39 community types were identified by the Brown-Blankuet method; their taxonomical and structural characteristics are described; the associations with biotopes are outlined; and a biotopical nomenclature is proposed. All communities are subdivided into four biotopical classes: crenal (springs and springbrooks with mixed substrates), rhitral (stony and woody substrates), phythal (macrophytes), and pelal (soft ground). It is shown that all communities may be divided by their organization as R-type of M-type community. 36 out of 39 studied communities belong to R-type and are characterized mainly by prevalence of insect, unstable dominance, and rather distinct association to the biotope. In M-type communities (3 out of 39 studied communities) eurybiontic mullusk Viviparus viviparus and amphipod Dikerogammarus haemobaphes predominate; these communities are interbiotopic, with stable species structure and high total abundance. The effect of the study spatial scale on the definition of communities is discussed along with problems of the communities dynamics.  相似文献   

8.
On the basis of long-term count of insectivorous mammals, the zonal, landscape, and biotopical distributions of their species and communities in the Upper Ob region have been characterized. Landscape-dependent variations in the species composition and dominance structure, as well as population density and species richness of the communities of insectivores have been estimated.  相似文献   

9.
大亚湾澳头水域浮游植物群落结构及周年数量动态   总被引:16,自引:0,他引:16  
对1997年至1998年广东省大亚湾澳头水域的浮游植物群落进行调查和分析。结果发现浮游植物65属198种;硅藻在种类组成和数量上都比甲藻占有优势,存在春季和秋季高峰,主要优势类群依次是角毛藻、骨条藻、拟菱形藻等;甲藻只存在春季高峰,代表种类有裸甲藻、原甲藻等。主要优势种类的生长与调查水域的盐度没有明显关系,但全年水温的季节性变化对优势种类的消长影响显著。Simpson多样性指数、Shannon-Weaver多样性指数、均匀度的年平均值分别是0.611、2.107、0.557,多样性指数没有明显的季节变化规律和水平分布规律。    相似文献   

10.
An annotated list of leaf-beetle species is given. It includes 76 species of 33 genera of 9 subfamilies, with Cryptocephalinae and Chrysomelinae predominating (42%). The insects were collected in different ecosystems of Mordovia, of them, 11 being pests of crops and forests, especially Phyllotreta vittula, Oulema melanopus, Leptinotarsa decemlineata, Chrysomela populi, Ch. tremula, Plagiodera versicolora, and Agelastica alni. Ecological and biotopical characteristics of the species are given: distribution ranges, preferred biotopes and host plants, periods of activity, flight, and egg-laying, thermal and humidity preferenda. Most species appeared to be mesophilous (71%), xerophilous ones constitute 13.2%, hydrophilous 10.6%, hygrophilous ones are not numerous (5.3%). Of all the species, 78% are heliophilous, and 22%, umbrophilous.  相似文献   

11.
梁健  李金钢 《兽类学报》2004,24(4):322-328
利用生物量、物种数、多样性指数、均匀度指数等变量, 对延安人工林区小型兽类群落的季节性变化进行了调查。选择生物量作为小型兽类的优势度指标, 分析了小型兽类优势度的季节性变化及在不同生境的表现。共捕获小型兽类9 种, 分属2 目3 科, 优势种为达乌尔鼠兔和中华鼢鼠甘肃亚种; 小型兽类群落4 种变量的季节变化与小型兽类种群生物量的季节变化关系密切; 延安人工林区小型兽类群落优势种的季节性决定着群落生物量的季节性, 普通种和稀有种的季节性决定着物种数和多样性的季节性; 延安人工林区9 种小型兽类存在不同的时空组合; 中华鼢鼠是唯一在各季节和所有生境中分布的种类; 夏、秋季刺槐人工林区、杂草灌丛区达乌尔鼠兔优势度极高。  相似文献   

12.
胶州湾多毛类环节动物优势种的生态特点   总被引:9,自引:0,他引:9  
根据1998-2004年春、夏、秋、冬四季对胶州湾进行大面站综合调查监测的底栖生物多毛类资料,分析了多毛类优势种的季节变化和年际变化。结果表明:不同季节多毛类优势种组成和优势地位出现一定的变化,但不倒翁虫(Sternaspisscutata)、寡鳃齿吻沙蚕(Nephtysoligobranchia)和中蚓虫(Mediomastuscaliforniensis)在各季度月优势地位相对稳定;考察1998-2004年不同年份的多毛类优势种,发现不倒翁虫、寡鳃齿吻沙蚕在各个年份均居优势地位,变化较小,而其它的种类在不同的年份出现一定的变化,2003年和2004年索沙蚕(Lumbrinerislatreilli)优势度居首位,而在其它年度则没有成为优势种,这可能反映了近年来胶州湾生态环境出现了一定变化;通过考察主要优势种的分布和密度变化,可以发现这几个主要种都是广分布的小型种,在底质颗粒较细,有机质含量丰富的海域,不倒翁虫、中蚓虫、寡鳃齿吻沙蚕等数量较大;而在水流湍急、底质为砾石的7号和9号站,则很少分布,这也反映了底质对多毛类的分布有决定性影响  相似文献   

13.
2015年4至12月,以玉龙鼠疫疫源地的核心区域文笔山为样区,在2 400 m以上海拔区间划分4个垂直生态带,采用夹夜法进行四个季节的小型兽类调查.根据生态位宽度指数(Bi)和生态位重叠指数(Cih)对该地区小型兽类垂直空间与季节生态位特征进行分析.调查共布鼠夹8 028次,捕获小型兽类1 583只,包括4目6科12属...  相似文献   

14.
The species (cytospecies) structure and seasonal dynamics of a thermophilic bluegreen algal/bacterial community from Mimbres, New Mexico are described. Using stereological techniques, several common quantitative ecological parameters (biomass, density, distribution measurements, Species Diversity Indices, importance values) were described for the community growing ca. 1 m beneath the water surface on the inner walls of a concrete cistern. Temperature and pH were relatively constant while water flow rates, duration and intensity of light showed seasonal variation. The total volume of the mat occupied by living organisms did not exceed 2% during the entire year. The remaining volume was occupied by gas and water bubble chambers, gelatinous matrix, empty tubes, mineral deposits, and water. The total biomass remained constant except during a period of severe, seasonal light reduction (November). Species Diversity Indices, density and importance values for the bluegreen algal and bacterial populations showed seasonal changes. The three dominant bluegreen algal cytospecies which represented the greatest amount of biomass alternated in their abundance on a seasonal basis while the three dominant bacterial cytospecies remained the same throughout the period of study. Although considerable season change occurred in the species structure of this community, the total living volume remained relatively constant with the major changes in the bluegreen algal populations. Many of the seasonal changes observed appear to correlate with seasonal changes in light intensity and duration.  相似文献   

15.
厦门港潮间带蛇尾类动物群落生态的研究   总被引:1,自引:0,他引:1  
  相似文献   

16.
福建中部近海浮游动物数量分布与水团变化的关系   总被引:4,自引:0,他引:4  
田丰歌  徐兆礼 《生态学报》2012,32(4):1097-1104
根据2009—2010年在福建中部近海24°55'—25°13'N、119°11'—119°32'E水域冬、春、夏3个季节的调查资料,探讨了该水域浮游动物总丰度与生物量的平面分布、季节变化及其与台湾海峡水团变化的关系。结果表明,调查水域浮游动物的数量在冬、春之交变化较大,而在春、夏季变化较小。浮游动物冬、春两季的平均丰度分别为8.90 个/m3和245.65 个/m3,夏季为236.82 个/m3。冬、春两季,该水域浮游动物的分布特征相近。其数量在近岸较高,向外侧水域逐渐降低。冬季浮游动物的丰度最高为31.56 个/m3,春季最高达到831.67 个/m3。中华哲水蚤(Calanus sinicus)是冬、春季影响总丰度变化最主要的种类。与冬、春季不同,夏季浮游动物的数量在离岸水域较高,丰度最高达1053.13 个/m3,而在近岸较低,最低值仅19.17 个/m3。汉森莹虾(Lucifer hanseni)、双生水母(Diphyes chamissonis)是影响总丰度变化最主要的种类。浮游动物在各季的不同分布特征与台湾海峡的季节性水团变化有关。受季风转换影响,从冬季到夏季,海峡内沿岸流势力逐渐减弱,台湾暖流水势力逐渐增强,并影响到沿岸的水文环境。这导致调查水域内浮游动物的优势种类由暖温种向暖水种演替。由于冬、春季的重要优势种类中华哲水蚤与夏季的汉森莹虾、双生水母具有不同的温度适应性,受不同性质水团的影响,在近岸和离岸水域各自呈现出不同的数量高低。从而进一步影响到各季浮游动物总数量的分布。  相似文献   

17.
Aedes aegypti (L.) and Aedes albopictus (Skuse) were surveyed using ovitraps in residential areas in Chiang Mai, northern Thailand. Egg populations (both species inclusive) remained low in the dry season, but increased/decreased exponentially during the first/latter half of the rainy season, respectively. This seasonal pattern was similar to the seasonal distribution of dengue haemorrhagic fever cases in the area. During the dry season (November-March) Ae.aegypti was dominant in urban and indoor ovitraps. With onset of the rainy season in April, relative abundance of Ae.albopictus increased in rural and outdoor ovitraps. Ae.albopictus displaced Ae.aegypti in the latter half of the rainy season in the rural area. Possible mechanisms to account for this seasonal decline of Ae.aegypti and reciprocal fluctuations in relative abundance of Ae.albopictus are discussed in relation to food availability for larvae in container habitats.  相似文献   

18.
The composition, species richness and diversity of a coastal fish assemblage from the Kalpakkam coast of south‐east India are described along with temporal distribution patterns related to seasonal fluctuations in dissolved oxygen, salinity, pH, chlorophyll‐a, phytoplankton and zooplankton species richness and density. A total of 244 fish species belonging to 21 orders, 87 families and 163 genera were recorded. The fish assemblage was dominated by reef‐associated species, followed by demersal species. The majority of the species (63%) are widely distributed in the western Indo‐Pacific as well as in the central Indo‐Pacific. Jaccard's coefficient analysis showed three distinct seasonal patterns of fish occurrence: pre‐monsoon (PrM), monsoon (M) and post‐monsoon (PoM). The maximum number of species was during the PrM period, followed by the PoM and M periods. Species occurrence analysis showed Sardinella longiceps to be dominant during PrM and M periods, Leiognathus dussumieri during the M period and Secutor insidiator and Secutor ruconius during the M and PoM periods. Canonical correspondence analysis indicated that salinity and rainfall were the two most influential environmental factors strongly correlated with temporal variation in the fish assemblage. The physico‐chemical conditions, in combination with factors such as greater food availability and shelter, might control the seasonal local distribution of the ichthyofauna in these Indian coastal waters.  相似文献   

19.
刘颖  田斌  欧光龙 《广西植物》2022,42(3):460-469
为揭示湿润常绿阔叶林和半湿润常绿阔叶林替代分布的气候制约变量,该研究选择其代表性优势树种青冈(Cyclobalanopsis glauca)和滇青冈(C.glaucoides)为研究对象,收集两个物种的标本分布点数据和19个生物气候变量图层数据,运用MaxEnt模型,模拟其潜在分布区,通过判别分析(DFA)、方差分析(...  相似文献   

20.
Results of the first long-term investigation of the profundal chironomid fauna of Starnberger See, a prealpine lake are reported. Data are presented on the qualitative and quantitative composition of the chironomid fauna in the profundal of Starnberger See, on the spatial variation, and on the phenology of the dominant species, based on pupal occurrence and the seasonal distribution of larval instars. Twenty-five distinct chironomid taxa could be recorded in the profundal zone. Typical inhabitants of the profundal zone of Starnberger See are the larvae of the genus Micropsectra. The maximum abundance of Micropsectra larvae were found at 60 m with 5644 Ind.m−2. Abundance, distribution and phenology of the dominant chironomid species are discussed in comparison with other lakes.  相似文献   

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