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1.
本文是《甲壳动物的生殖量与环境关系》系列论文的第二篇,专述桡足类。它和枝角类一样,是一类小型低等甲壳动物,也是浮游生物群落的一个重要组成部分。种类多、数量大、分布广是它的生态特点。由于生活习性不  相似文献   

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本文是《甲壳动物生殖量与环境关系》系列文章的第三篇,也是最末篇,专述其他甲壳动物,包括鳃足类、介形类、蔓足类、涟虫类、等足类、端足类、糠虾类、磷虾类,以及十足类(含樱虾类、真虾类、海螯虾类、龙虾类,及寄居蟹类、蟹类)和口足类的生殖量和环境关系。本文内容也分为“生殖量变化”和“生殖量和环境关系”二大部分。这样,可与前二篇作对比研究,从而找出其异同点。并为探索生殖量变化机制及规律,打下理论基础。  相似文献   

4.
栖息面积对果蝇生殖量的影响   总被引:1,自引:0,他引:1  
许祖国 《遗传》1992,14(4):21-22
  相似文献   

5.
中国林蛙的生殖量特征及其地理变化   总被引:21,自引:0,他引:21  
卢欣 《生态学报》1994,14(2):209-214
标本采自山西省境内的8个地点。结果表明1研究区域内性成熟雌蛙平均体长范围是34.5-52.3mm,高山森林带种群明显偏高;研究种群雌蛙的体长显著低于东北居群。2平均生殖量的范围是422.4-840.9枚,个体的最低,最高值分别为38和1978枚,平均相对生殖量的范围是10.7-18.0,个体的最低,最高值各为1.3和34.4。与东北居群相比,生殖量的变异幅度较高。3除高山森林带外,其余调查点的生殖  相似文献   

6.
侯苹  张娴文  白洁 《生命科学》2013,(11):1121-1125
环境激素(environmental endocrines,EEs)是外源性激素,可模拟体内天然激素与机体内的受体以及相应靶点结合,导致内分泌系统以及生殖系统功能紊乱。环境激素所产生的效应十分复杂,因此,进一步明确其毒性机理将为环境激素所致危害的预防和治疗提供理论依据。就环境雌激素的生殖、发育等毒性机理作一综述。  相似文献   

7.
生殖内分泌是调控鸟类繁殖行为的重要生理过程,环境因子则是影响鸟类生殖内分泌的关键因素。光周期是调节大多数温带鸟类生殖内分泌的关键环境因子。日照延长可作用于下丘脑一垂体一性腺轴(HPG)刺激繁殖活跃,日照缩短则刺激下丘脑释放GnIH抑制繁殖。在沙漠、热带地区以及食物条件不可预见的地区,降雨、食物及温度也可成为影响鸟类生殖内分泌的重要因素。环境内分泌干扰物等人类活动因素也会对野生鸟类的生殖内分泌产生一定的影响。  相似文献   

8.
表皮生长因子与哺乳动物生殖的关系岳占碰杨增明(东北农业大学生物工程系哈尔滨150030)关键词表皮生长因子哺乳动物生殖表皮生长因子(epidermalgrowthfactor,EGF)是一种多肽类生长因子,该因子在人和动物各种组织器官生长发育过程中是...  相似文献   

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环境内分泌干扰物(environmental endocrine disruptors,EEDs)是指环境中天然存在或污染的能够干扰机体内自然激素的合成、分泌、转运、结合、作用和消除等过程,表现出拟自然激素或抗自然激素的生理学作用的一类化合物。它们与人们的生活密不可分,比如邻苯二甲酸酯类(PAEs)和双酚A(BPA),就广泛存在于食品包装、儿童玩具及生活用品中。大量实验证据以及流行病学的调查表明环境内分泌干扰物对动物雌激素、睾酮、甲状腺素、儿茶酚胺等呈现显著的干扰效应,是生殖障碍、出生缺陷、发育异常、代谢紊乱以及某些恶性肿瘤的发病率增加的原因之一。本文归纳了环境内分泌干扰物(EEDs)对生殖健康影响的研究进展。  相似文献   

11.
赵文  余博识  王婷  宋亮 《应用生态学报》2006,17(8):1521-1525
为了解淡水枝角类对海水盐度的适应性,在实验室内采用种群实验生态学方法研究25 ℃±0.5 ℃恒温条件下不同盐度(0、1、2、3、4、5)对近亲裸腹溞(Moina affinis)生存、生长和生殖的影响.结果表明,在各盐度梯度范围内,近亲裸腹溞的平均寿命随盐度升高而缩短,盐度4和5组内禀增长率与其它各组差异显著;盐度4和5组平均每窝产幼量与对照及其他组差异显著.一生产幼量除盐度1组和对照组较高外,其他各组均显著下降.对照组体长增长幅度与日增长率均低于各处理组.日增长率随着盐度的升高而增大.个体平均每胎产幼量以盐度1、2组最高.盐度5为近亲裸腹溞的生存和生殖盐限,但经过短期的海水驯化,其生殖耐盐上限有所提升,可达6.5.  相似文献   

12.
The genus Bosmina can be differentiated into four subgenera: 1. Bosmina s. str. BAIRD , 1845, 2. Eubosmina SELIGO , 1900, 3. Neobosmina LIEDER , 1957, and 4. Sinobosmina LIEDER , 1957. Subgeneric discrimination is based upon several features of the females (postabdominal claw, serration of the mucro, patterns of the lateral head pores) and, mainly, upon certain differences in the morphology of the male (postabdomen and, according to LILLJEBORG 1900, BURCKHARDT 1924 and KOŘINEK 1971, the first leg). The distribution of the Bosmina subgenera throughout the world varies: Bosmina s. str. is distributed worldwide (except for Australia?), Eubosmina is holarctic, Neobosmina has been found in Africa, the neotropical zone, Australia and Oceania, and Sinobosmina occurs in East and South-East Asia.  相似文献   

13.
Contrary to some localities in France and Spain, Cladocera occur in hypogean waters in Yugoslavia very sporadically. Beside the stygobitic species, Alona hercegovinae from caves and Alona smirnovi from interstitial waters, particularly some other Chydoridae seem to be suited for hypogean life. Chydorus sphaericus, reputed as one of the most euryoecious cladocerans, occurs also the deepest in interstitial waters as well as in caves. Other species, found in hypogean waters are Simocephalus vetulus, Ilyocryptus sordidus, Eurycercus lamellatus, Chydorus ovalis, Leydigia leydigi, Acroperus harpae and Biapertura affnis.  相似文献   

14.
Populations of theDaphnia hyalina-galeata complex from Central, North and South Europe have been compared morphologically. The main purpose of this investigation is delimitation of the critical speciesDaphnia galeata, based on a thorough examination of the original materials from G. O. Sars' collection, and taking into account hitherto overlooked or insufficiently appreciated characters. According to their morphology and ecology,Daphnia hyalina, Daphnia galeata andDaphnia cucullata have to be treated taxonomically as separate species. In view of the short and high antennula mound and other morphological characteristics,Daphnia gracilis Hellich andDaphnia hyalina lacustris sensu Lilljeborg belong to the speciesDaphnia galeata. In the common range ofDaphnia galeata andDaphnia cacullata there occurs quite frequently an intermediary form, which according to genetic evidence is a hybrid of these two species. Although apparently this hybrid form is stabilized genetically to a large extent and is capable of identical reproduction, it should not be considered as a species in the usual sense.The present work intends to put the notoriously confused systematics of theDaphnia hyalina-galeata complex on a firm basis. It concludes with a key, which should enable also non-specialists to identify uniquely the three species and the hybrid form in question.  相似文献   

15.
Hudec  Igor  Illyová  Marta 《Hydrobiologia》1998,368(1-3):65-73
Pleuroxus denticulatus Birge, 1879 is a new invader from Western to Central Europe. Its occurrence in a Danube inundation (Slovak region) probably corresponds with the junction of the Danube and Rhine Rivers. The species was found among ‘the hard macrophytes’ of flowing arms and artificial ponds. A large variability was recorded in the number of valval denticles and in postabdominal denticulation. It is evident that part of the N. American populations is different from European populations. P. denticulatus seems to represent two sibling species. Both are characterised by an angular distal postabdominal corner, bearing 3–4 denticles, and by valval denticles on the postero-ventral corner. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

16.
Igor Hudec 《Hydrobiologia》1990,190(1):33-42
Moina weismanni Ishikawa is reported from Czechoslovakia, Hungary, and Yugoslavia. The species was formerly synonymized with Moina micrura Kurz, based on parthenogenotic females. In both species, parthenogenetic females have a characteristic postabdomen, antennules (characters formerly regarded as typical for a variety of M. micrura), and ephippium. Wales are quite different. Examined populations of both species are similar in length-to-width ratio. M. weismanni is typical for small, eutrophic but permanent, and for large temporary water bodies. M. micrura is restricted to the plankton.  相似文献   

17.
Global diversity of cladocerans (Cladocera; Crustacea) in freshwater   总被引:1,自引:0,他引:1  
Cladocera is a primarily-freshwater monophyletic group, an important component of the microcrustacean zooplankton. They inhabit most types of continental fresh and saline water habitats, occurring more abundantly in both temporary and permanent stagnant waters. Cladocera is an ancient group of Palaeozoic origin. About 620 species are currently known, but we estimate that the real number of species is 2–4 times higher. A number of currently-recognised widespread species can be expected to harbour extensive cryptic diversity. Guest editors: E. V. Balian, C. Lévêque, H. Segers & K. Martens Freshwater Animal Diversity Assessment  相似文献   

18.
A new species of Cladocera, Moina mukhamedievi from ricefields of Uzbekistan, is described. It is compared with the related species M. dubia, M. brachiata, M. oryzae. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   

19.
Ninetysix species of Cladocera, comprising 8 Sididae, 50 Chydoridae, 17 Macrothricidae, 5 Moinidae, 2 Bosminidae, and 14 Daphniidae, occur in tropical Australia. Of this number 38% are cosmopolitan including so-called cosmopolitan species, 13.5% are circumtropical, 13.5% occur as well innear by countries, and 35% are endemic. North Queensland is a major area of speciation. Species richness varies from north to south and from wetter coastal areas to the drier inland. Major factors influencing richness and distribution are the relative proportion of floodplain billabongs in an area, coupled with rainfall reliability. The most common species include Alonella clathratula, Chydorus nr. pubsecens, Macrothrix triserialis, Oxyurella singalensis, Ephemeroporus nr. barroisi, Dadaya macrops, Diaphanosoma sarsi, Ceriodaphnia cornuta, and Dunhevedia crassa.  相似文献   

20.
Twelve species ofCeriodaphnia were examined by light and scanning electron microscopy for the presence of head and carapace pores. Rostral pores, similar to those in the Scapholeberinae (Dumont & Pensaert, 1983) were found in all species, situated just anterior to or between insertions of the antennules. With two exceptions, the pattern of reticulations around the pores was distinctive for each species. Oval ‘head pores’ or fenestrae occur consistently on the anterior surface of the cervical notch of juvenile and adultC. dubia, cf.dubia (from Australia),lacustris, andreticulata. The patterns of reticulations around a fenestra are unique to each species. It appears thatC. cornuta (s.l.) in the Americas has a fenestra, whereas AustralianC. cornuta (s.s.) has none. Minute pores often occur bilaterally anterior and posterior to the cervical notch in heavily reticulated individuals of several species but are not constant enough to be taxonomically useful. Well-defined small pores are situated within narrow reticulations just medial to the ventral and posterior valve margins ofC. dubia, lacustris, andreticulata. These open into carapace glands of unknown, perhaps secretory, nature. Similar glands have been observed in related taxa. Such glands and marginal pores occur only occasionally or not at all in otherCeriodaphnia. Other small pores sometimes occur among reticulations of the head, fornix, and lateral and antero-ventral surfaces of the valves. They are found more often in juvenile or heavily reticulated individuals. As yet no consistent pattern to their occurrence among species has emerged. Head and carapace pores inCeriodaphnia may be most useful in identifying species rather than in determining species groups or evolutionary patterns within the genus.  相似文献   

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