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1.
The correlation between the timing of adult emergence and variation in morphophysiological parameters of males and females has been analyzed in the black-veined white Aporia crataegi L. In 2013 to 2015, black-veined white butterflies were collected from a natural population in the south of Sverdlovsk oblast throughout the emergence period; at the same time, adult insects were reared from pupae in individual cages. Comparison of the field observations in nature and the results of rearing preimaginal stages has shown that the largest adults are the first to emerge, while the smallest are the last to emerge. This pattern holds true both for the parameters varying throughout the adult insect life (body weight and relative abdomen weight) and for the permanent characteristic of the “structural” size (wing area). The influence of protandry and food availability to caterpillars on the variation in the size of adult A. crataegi during the period of generation emergence is discussed.  相似文献   

2.
Specific features of larval feeding in two geographic populations of the gypsy moth are considered. It is shown that in larvae reared on an artificial diet, trophic indices depend on several factors, including the age and sex of larvae and the food plant on which the parental generation developed in nature. It is shown that larval micropopulations belonging to the same geographic population but feeding in nature on different plant species differ from each other to a greater extent than those of different geographic populations feeding on the same species.  相似文献   

3.
The annual relative mass of storage organs cycle of Bufo gargarizans in southwestern China was studied from December 2005 to November 2006. We described how those organs changed in response to extreme temperatures. Energy reservation dropped to the lowest levels after dormancy for both sexes, and then increased for period of 4.25 month. However, the mass of these organs dropped again rapidly until August (liver) and September (fat bodies) due to the constraint from extreme high temperature occurred during the summer, and then non-significantly increased before hibernation. For ovaries, varied with a different profile to those of liver and fat bodies have a resting period of four months. In addition, the toads’ ovaries kept growing when the mass of liver and fat bodies declining accordingly during hibernation. Therefore, ovarian mass increased during the hibernation and non-hibernation period.  相似文献   

4.
The patterns of growth and development have been studied in L. maculatus early life stages of different ecological groups (pelagic and demersal) from Kongsfjorden and Billefjorden (the northwestern coast of West Spitsbergen). It has been found that the growth rate of larvae markedly increases by age 2+ (stage L2), which is due to their transition to exogenous feeding. Consideration is given to changes in the length and condition of the lipid sac (a provisory organ) in the period of its formation, growth, and resorption in the course of ontogeny. The lipid sac reaches the maximum size at stage L4* and is resorbed at stage L5. Analysis of individual variation in the size and body weight of fish early life stages provides the possibility to evaluate the adaptation capacity of a species under specific conditions of the Arctic.  相似文献   

5.
With regard to published data on the ecology of early peled larvae acclimated in lakes or reared under experimental or fish farm conditions, interannual variability of feeding and environmental conditions during the transition to exogenous feeding has been demonstrated for peled larvae in a control water body located in the floodplain of the main spawning tributary of the lower Ob River. The conditions that govern exogenous food consumption by early peled larvae and largely determine the fate of a given generation depend on both biotic (the concentration of food organisms) and abiotic factors (wind regime). The trophic optimum during the transition of larvae to exogenous feeding, which ensures the level of gut filling sufficient for their survival and growth in the control water body, is determined by a complex of natural events. The results of this study may be extrapolated to the entire native range of the Ob River peled population and used for planning the release of peled larvae into natural water bodies of Western Siberia to compensate for losses to their biological resources.  相似文献   

6.
1962~2012年西南地区极端温度事件时空变化特征   总被引:2,自引:0,他引:2  
基于西南地区88站1962~2012年日气温数据,采用百分位阈值法定义极端温度事件,结合线性倾向率、Mann-Kendall秩次相关法、反距离加权插值法对其时空变化进行了分析。结果表明:极端温度指数存在明显的空间分布差异,暖日指数、暖夜指数、冷夜指数和年内日最低气温整体上均由东南向西北逐渐降低;霜冻天指数则由东南向西北部逐渐升高,西北部梯度变化明显;冷日指数和年内日最高气温呈马鞍状分布,较高值均在西南和东北部;因多数地区高温天数极少,故没有明显的梯度变化。霜冻天指数、冷夜指数和冷日指数减少趋势明显,分别为2.7、4.6和3.5d/10a;暖日指数和暖夜指数、年内日最低气温和最高气温均呈增加趋势,分别为3.6、4.9、0.4和0.1℃/10a;高温天指数变化不显著。整体上来看,西南地区极端高温事件和极端低温事件分别呈上升和下降趋势,但有部分区域呈相反变化趋势,体现出西南地区气候变化的独特性。  相似文献   

7.
We tested separately the effect of two taxonomically related rotifers (B. patulus and B. macracanthus) on the population dynamics of another species (A. fissa) at low (0.5 ×10 6) and high food levels (1.5 × 106 cells/ml of Chlorella vulgaris) using different inoculation densities (0–100%). We also quantified the impact of A. fissa on the two brachionid species. Regardless of the presence of the competing species, an increase in the availability of food led to increase in the abundances of the three rotifers. The population growth of B. patulus, B. macracanthus, or A. fissa was affected negatively when cultured together with another species. An increase in the initial density of any one of the competing species became advantageous to maintain a certain population size. At a low algal food level, B. patulus was able to suppress A. fissa more strongly than B. macracanthus. On the other hand, at a high food level, B. macracanthus suppressed the population of A. fissa more strongly than B. patulus. Peak population densities for A. fissa varied from about 150 to 1000 ind./ml, depending on food density and the presence of competitors. The rate of population increase (r) of A. fissa, B. patulus, and B. macracanthus increased with an increase in food availability but decreased with increasing initial density of the competitor. Both Brachionus spp. experienced negative growth rates in the presence of A. fissa, especially at a high initial density of the latter. Published in Russian in Ekologiya, 2007, Vol. 38, No. 5, pp. 381–390. The article was submitted by the authors in English.  相似文献   

8.
Populations from different environmental habitats indicate variation in life history traits and these differences are mostly related to longevity, age and size at maturity. In this study, age structure, longevity, survivorship and sexual size dimorphism of Near Eastern fire salamander (Salamandra infraimmaculata) were assessed by means of skeletochronological analysis. Maximum lifespan was recorded to be twelve years in females and eleven years in males and age at maturity was estimated as three and four years for both sexes. Females had significantly larger SVL than that of males, while age structure and mean age did not differ between sexes. Age and body size were positively correlated with each other for both females and males. Since the populations of the Near Eastern fire salamander in Turkey are in decline, the present study which provides preliminary data on life history traits of this species could be helpful for future biological studies.  相似文献   

9.
Using methods of geometric morphometrics, significant differences have been revealed in manifestations of variability and morphological disparity in allochronous samples from the population of model species, the bank vole (Clethrionomys glareolus Schreb. 1780), in the Middle Urals at different levels of rodent community (taxocene) completeness in different years. Two states of the taxocene—oligospecific (two species) and polyspecific (five species)—and the level of relative abundance of bank voles (high or low) have been taken into account. Comparative analysis of variation in the size and shape of the mandible in same-aged (late-summer) young of the year has shown that significant morphogenetic differences exist between the animals sampled from the rodent taxocene at its different states (oligospecific and polyspecific) and, to a lesser extent, at high and low levels of abundance. The level of variation and the parameter of intragroup morphological disparity (MNND) in the mandible shape reach a maximum when the community has a reduced composition and decrease to a minimum when its composition is complete (i.e., in the oligo- and polyspecific taxocene). A parallelism is observed in the manifestation of morphofunctional changes of the mandible in male and female voles under conditions when the taxocene has high abundance and oligospecific composition or low abundance but polyspecific composition. Different morphogenetic responses of the population to oligo- and polyspecific composition of the community are considered as a compensatory increase of morphological disparity in the dominant species (the bank vole) under conditions of incomplete composition of the taxocene and low population density, in accordance with Chernov’s ecological compensation principle.  相似文献   

10.
Downstream migration (larval drift) of coregonids in the lower reaches of the Severnaya Sos??va River (the largest spawning tributary of the Lower Ob) has been analyzed from ecological aspects such as the long-term, seasonal, and daily dynamics and the spatial distribution, growth, and feeding of larvae in the current. Considerable changes in the abundance of coregonid generations have been revealed. It is shown that downstream larval migration over a long route has a number of features distinguishing it from that at spawning grounds. In particular, mass migration takes place after the ice drift, and its intensity is independent of changes in flow discharge. The drifting larvae display species-specific distribution in the current, and their density is the lowest in the surface water layer. In the course of migration, their linear body growth is accompanied by considerable depletion of endogenous food reserves and transition to active feeding.  相似文献   

11.
气候变暖已成为近几十年研究的热点,但是有关温度升高对螺类形态变化的研究还为数不多。利用中型室外模拟控制系统(Mesocosm)模拟百年之后长江中下游地区浅水湖泊水生态系统,实验设置对照组与升温组两个处理,以此探求水体温度升高对铜锈环棱螺(Bellamya aeruginosa)形态的影响。应用几何形态测量学得到铜锈环棱螺壳高、壳宽、轮廓面积与周长4个形态参数,并分别与质量进行回归分析。通过协方差分析比较两种处理回归方程的差异,发现螺类周长随温度升高发生显著变化,同时升温增加了螺类春季个体增补数量。升温对于螺类形态变化影响体现在以下3方面:升温显著增加了铜锈环棱螺的密度,加剧了种群个体间竞争,促使性成熟个体趋于小型化;升温改变铜锈环棱螺食物质量,通过影响螺类生长过程对螺类形态变化产生作用;升温改变了水体p H值,进而影响螺类外壳的钙化率和水体中钙可利用程度,对螺类外壳形成产生直接的影响,最终导致螺类形态变化。  相似文献   

12.
Evaluating the effects of fishing and environmental factors on fish populations are fundamental tenets of fisheries science. In this study, we assess associations between environmental variables (sea surface temperature; North Atlantic Oscillation index; upwelling; wind magnitude; westerly winds; northerly winds; river discharge) and fishing variables (fishing effort) in Diplodus sagus catch rates accounting for regional analyses (northwest coast; southwest coast and Algarve—Algarve south coast). Different time series models for data fitting (multi-model approach) were used. The models were lagged, according to species fishing recruitment age based on the hypothesis that fisheries catches depend on larvae recruitment and survivorship. D. sargus catch rates across areas were unrelated to fishing effort but correlated to environmental variables, with seasonal events explaining much of the variability in trends. On the northwestern coast, the catch rates were mainly set by sea surface temperature (SST) and wind magnitude; however, southwestern coast catch rates were set by NAO winter. On the south coast, only one statistical model (SST, upwelling and westerly winds) associated spring conditions with D. sargus catch rates. The multi-model approach revealed autumn, winter and spring seasonal effects to be related with northwest, southwest and Algarve coastal catch rates, respectively, indicating a possible coastal longitudinal gradient related with given periods of spawning and larval availability. The metadata analysis yielded different results from the regional analyses. In summary, marine resource management should take regional environment characteristics and variability into account when determining sustainable catch rates in given areas for species with high habitat site fidelity.  相似文献   

13.
The seasonal variation of forewing size and shape was analyzed in adults of different seasonal generations of two polyvoltine species of whites: Pieris rapae and P. napi (Lepidoptera: Pieridae). Particular morphological features of the forewing are characteristic of each seasonal generation of adults independently of their sex and species. Adults of the spring generations have the smallest wings, elongate and pointed. Adults of the summer generation have the largest, broad and rounded wings over the entire summer season. Adults of the autumn generation have wings similar in shape and size to those of the summer generation, but somewhat smaller and more elongate. Differences between seasonal generations in forewing shape are linked to differences between adults of each generation in adaptation to dispersal.  相似文献   

14.
Phenotypic variation in the widespread Siberian and Mongolian butterfly species Coenonympha amaryllis (Stoll, 1782), an indicator of undisturbed steppe communities, is analyzed. It is shown that its size variation is influenced by a complex of climatic factors, the most important of them being the average starting date of the frost-free period and average annual temperature in the region. Longitude-dependent variation in size is described by a “sawtooth curve” characteristic of species with changing voltinism.  相似文献   

15.
为进一步揭示鄱阳湖流域极端气温事件变化及其影响因素,基于鄱阳湖流域24个气象站点连续59年观测资料,选取8个极端气温指数,分析鄱阳湖流域极端气温动态变化,并探讨了大气环流与极端气温变化的联系.结果表明:(1)鄱阳湖流域极端气温暖指数(暖昼天数、暖夜天数和夏日天数)及极值指数(日最低气温最小值和日最高气温最大值)均呈增加趋势;冷指数(冷昼天数、冷夜天数和霜冻天数)均呈逐渐减少趋势.(2)从空间分布来看,极端气温空间变化趋势与年际变化一致,极端气温暖指数和极值指数呈增加趋势,冷指数均呈减少趋势,但在不同地区变化趋势存在差异.流域各站点霜冻天数和冷昼天数均呈显著下降趋势,但在赣北地区下降趋势最显著.大部分站点(23/24)暖夜天数、夏日天数和日最低气温最小值均呈显著增加趋势;(3)鄱阳湖流域极端气温指数的变化与大气环流的变化存在相关性,其中西太平洋副高强度指数、夏季东亚季风指数、亚洲区极涡强度指数和北极涛动指数对极端气温事件影响显著.研究结果可为极端气候风险评估、灾害预警提供参考.  相似文献   

16.
The effects of birch resistance induced by its artificial defoliation on the development of gypsy moth larvae and their sensitivity to viral infection and on the state of the antioxidant and detoxification systems of the insect midgut were studied. The dynamics of larval body weight; larval mortality and its etiology; glutathione-S-transferase (GT), nonspecific esterase (NE), and catalase (CAT) activities; and the ratio between the concentrations of oxidized and reduced thiol-containing compounds (RSSR/RSH) were estimated. In larvae feeding on the leaves of a previously defoliated plant, body weight was decreased, NE was inhibited, and the RSSR/RSH ratio was increased.  相似文献   

17.
Diet, food preferences and main ecophysiological characteristics such like energy requirements and thermoregulation characteristics of Mus spicilegus spicilegus (Petenyi, 1882) were studied. The most preferred foods for the mice were seeds of weed species that composed more than 85% of their diet. The results of food selection experiments shows that the total daily consumption by mice is 2.77 ± 0.76 g/animal/day or 5.5 kJ/g/day or 84.9 kJ/animal/day. From the total daily energy consumption 16.4% go back to nature in the form of feces and urine and the rest 83.6% animals utilized for assimilation. The results of the temperature preferences for Mus s. spicilegus shows preferred temperature zone from around 26 to 36°C where mice spent about 72% of the experimental time. The lowest value of oxygen consumption for resting metabolism rate (RMR) was registered at 30°C–3.20 ± 0.71 cm3 O2/g/h. It is possible to consider that the thermoneutral zone is around these temperature values. The obtained results give reason to conclude that from an ecophysiologycal point of view the climate in the south boundary of distribution provides optimal conditions for species development. The main cause for population decreasing probably is the loss of open habitats including natural steppe grasslands.  相似文献   

18.
A study has been performed on the ecological, morphological, and genetic diversity of burbot (sample size n = 204 and n = 134, respectively) from eight localities of the Ob–Irtysh and Taz river basins, Western Siberia. Fish differentiation in body size and weight depending on the dominant type of migration behavior, foraging conditions, and physiographic features of habitats has been revealed. A high genetic diversity (854-bp mtDNA control region) and a low level of between-sample differentiation is evidence for high intergroup gene flow.  相似文献   

19.
Body size-dependent mating pattern is thought to a consequence of the sexual selection on phenotypic characters. In the view, we investigated the mating patterns in Bufo andrewsi from three populations at different latitude in three Nature Reserves (i.e. Wanglang, Yele and Fengtongzhai) in China from early- March to late-May 2013 and 2014. The results showed that average body size did not differ significantly between amplectant and non-amplectant males within each population. We found a significantly positive relationship in body size between the amplectant males and amplectant females in Wanglang population, but not in Qiqiao and Yele populations. The strength of size-dependent mating was not correlated with the malebiased operational sex ratios (OSRs), suggesting that intensity of male-male competition at nights do not result in variation in size-dependent mating patterns in B. andrewsi among populations.  相似文献   

20.
To better understand how Batrachupems tibetanus responds to different temperature regimes in the blood parameters and to estimate the change in plasma cortisol level in this species exposed to different temperatures, the animals were stochastically divided into three groups and exposed respectively to 4.6°C, 14.6°C and 19.6°C for 12 days. The concentrations of glucose, total protein, albumin, triacylglycerol, Ca2+, K+, Na+, Cl, and plasma cortisol level were measured respectively. There was no significant difference between the plasma cortisol level of the control group and the experiment groups. Glucose level at 4.6°C and 19.6°C was significantly lower than glucose level at 14.6°C. The plasma triacylglycerol level was significantly influenced by acclimation temperature. The concentration of total protein, albumin, globulin and the ratio between albumin and globulin were not significantly influenced by temperature when compared with control group. There was no significant change in concentration of Ca2+ at different temperatures. The concentration of K+ was significantly influenced by temperature. Plasma K+ level significantly increased at 19.6°C. The plasma Na+ level and Cl were significantly influenced by temperature. Na+: Cl ratio was significantly influenced by temperature. Therefore, glucose, triacylglycerol, Na+ and Cl levels could be considered as indicators of thermal stress in B. tibetanus; plasma cortisol, albumin, globulin levels, and albumin/globulin ratio are not influenced by temperature.  相似文献   

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