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1954年夏季,中国科学院为了介绍我国重要动物,以适应国家经济建设和文化建设中人民对认识祖国动物日益增长的要求,成立了中国动物图谱编辑委员会,负责组织推动有关动物图谱的各项工作。 图谱的取材,有四项标准:(1)国内有经济关系的种类;(2)国内常见的种类;(3)国内著名的特产种类; 相似文献
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+Gz加速度负荷作用于人体,主要引起血液由头部向下体转移的血液动力学改变,进而使脑血容量降低,使视网膜和脑细胞缺血,引起黑视乃至意识丧失。对因+Gz加速度负荷引起动物头部血压降低,脑组织血流降低早有报道,但尚未见动物脑血容量动态变化规律的报告。我们用同位素示踪技术,标记家兔血液,测量在不同+Gz加速度作用下的兔脑血容量动态变化曲钱(以下简称脑血容曲线),并对曲线进行了拟合,为动物加速度耐力的研究,提供了一项新的技术方法。 相似文献
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土壤原生动物对环境污染的生物指示作用 总被引:17,自引:3,他引:17
土壤原生动物具有丰富的种类和巨大的生物量,在土壤生态系统中具有十分重要的地位.作为指示生物,土壤原生动物具有与其他土壤动物相比更独特的优势.研究它们的群落结构、数量及多样性动态变化,可以很好地评价和监测自然环境变化及人类活动带来的环境污染.本文根据国内外相关文献,简要概述了土壤原生动物在生态系统中的作用.对原生动物的生物指示物优势、土壤原生动物对环境因子响应和污染指示作用及对大气CO2浓度变化的响应等进行了论述,并对土壤原生动物在生态毒理诊断中的应用前景进行了展望. 相似文献
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为了解三门湾大型底栖动物群落的现状和动态变化,分别于2015年11月、2016年2月、5月和8月在三门湾海域用阿氏拖网对大型底栖动物进行调查。结果表明: 经鉴定,大型底栖动物有119种,主要类群为鱼类、甲壳类和软体动物,占种类总数的79%。大型底栖动物全年优势种为细螯虾、长额超刺糠虾和六丝钝尾虾虎鱼,不同季节优势种的变化明显,种类差异性较大。大型底栖动物的年平均生物量和平均栖息密度分别为0.025 g·m-2和0.07 ind·m-2。三门湾大型底栖动物各季节的Shannon多样性指数为2.21~3.18,Margalef物种丰富度指数为3.25~3.78,Pielou均匀度指数为0.53~0.79。ABC曲线分析显示,在春季和冬季,群落受到中等程度干扰;而在夏季和秋季,群落受到轻微扰动。典范对应分析结果显示,水深、温度、盐度和pH值是影响大型底栖动物群落的最主要环境因子。 相似文献
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Eduardo Domínguez Carlos Molineri William L Peters 《Studies on Neotropical Fauna and Environment》2013,48(2):87-101
The genus Farrodes was recently revised, and two species groups were delimited: Farrodes caribbianus and Farrodes bimaculatus. In that paper the species of the F. caribbianus species group were described or redescribed. In the F. bimaculatus species group eight undescribed species were treated but not described. In the present paper, these new species of the F. bimaculatus species group are described and discussed and a key for the separation of all the species known from male imagines in this group is provided. 相似文献
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在长岭草原共采到中气门螨9科15属20种。优势种为胸前下盾螨Hypoaspis praesternalis Willmann,1949,螨数和分布生境数最多,常见种有10种,稀有种为9种。在调查的20个生境中,羊草杂类草生境螨数和螨种数最多,碱茅生境没有采到螨,其余18个生境都采到不同数量的螨。 相似文献
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应用PCR—SSCP快速鉴定结构分枝杆菌复合群 总被引:12,自引:0,他引:12
通过聚合酶链反应(PCR)-单链的权象多态性(SSCP)技术分析结构分枝杆菌和非结构分枝杆菌临床株的16S rDNA基因。60例临床标本中,20例为阳性,与传统方法比较无差异。其中分型:18例为结核支杆菌,2例为结核分枝杆菌和非结核分枝杆菌双重感染。20例阴性标本中,PCR-SSCP又检查出5例阳性。20例对照标本中,3种传统方法与PCR-SSCP法均检测为阴性。全部试验3d执行结果。结核分枝杆菌 相似文献
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CHRISTOPHER J. PERUMALLA CAROL A. PETERSON DARYL E. ENSTONE 《Botanical journal of the Linnean Society. Linnean Society of London》1990,103(2):93-112
PERUMALLA, C. J., PETERSON, C. A. & ENSTONE, D. E., 1990. A survey of angiosperm species to detect hypodermal Casparian bands. I. Roots with a uniseriate hypodermis and epidermis. Roots of 181 species from 53 families were surveyed to determine the frequency of Casparian bands in hypodermal layers. For six species, inconclusive data were obtained. The roots of the remaining 175 species were divided into three categories on the basis of this survey. In the first, a hypodermis is absent (12 species): no wall modifications were observed in the outer cortex and this region was permeable to the apoplastic dye Cellufluor. In the second, a hypodermis is present, but a hypodermal Casparian band is absent (seven species). In roots of six species, no wall modifications were detected in the hypodermis; the one remaining species had lignified phi thickenings which were permeable to Cellufluor. In the third, both a hypodermis and a hypodermal Casparian band are present (156 species). These Casparian bands consisted of suberin deposits throughout the width of the anticlinal walls of the hypodermis. The tangential walls of the hypodermis were also suberized, indicating that suberin lamellae were probably also present. Hypodermal Casparian bands were found in roots of hydrophytic, mesophytic and xerophytic species and in members of primitive as well as advanced families. The widespread occurrence of these bands (in 89% of the species surveyed) suggests that they were present in the type ancestral to the flowering plants and that this feature has been retained by many species in this group. The epidermal cell walls of the majority of species examined were suberized but were permeable to Cellufluor. 相似文献
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通过对库姆塔格沙漠南缘植被进行实地调查,对该地区植物物种丰富度及其群落组成进行研究,并选取11个影响物种丰富度的气候因子和地形因子,利用PCA分析、方差分解等方法探讨气候、地形因子对物种丰富度的影响。结果显示:该区共有植物15科32属38种,植物群落种类匮乏,物种组成单一,植物生活型主要以灌木、多年生草本为主,占所有物种的80%以上;植物物种丰富度与植物群落组成明显受到水热条件的制约。回归分析结果表明,该区物种丰富度与能量因子呈显著负相关(P<0.05),而与水分因子呈显著正相关(P<0.05)。方差分解结果表明,水分、能量共同制约了该地区的物种丰富度,二者的共同解释率为44.3%。此外,地形因子对研究区物种丰富度也存在一定影响,能进一步提高环境因子对物种丰富度的解释率。总之,库姆塔格南缘物种组成单一、物种丰富度格局受到水热条件的共同制约,同时地形的变化也有重要影响。 相似文献
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分析了龙底自然保护区油料植物组成与资源特点。结果表明:(1)油料植物107科281属477种,其中精油植物131种,樟科(7属27种)、芸香科(6属21种)、唇形科(11属17种)等11个科为优势科,以木本植物为主,占73.38%。(2)以种子种皮为主要含油部位的植物占71.47%,植物含油量>20.0%的有211种,>50.0%的43种;油脂脂肪酸含量>70.0%的有7科11种,亚油酸含量>70.0%的有12科20种。(3)在精油植物中,57种植物含精油量>1.0%,13种>4.0%。龙底自然保护区内油料植物资源丰富,特别是富油植物资源种类较多,是油料植物富集之地,具开发利用潜力。 相似文献
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Although the distribution of plant species abundance in a Minnesota grassland was consistent with neutral theory, niche but not neutral mechanisms were supported by the ability of species traits to predict species abundances in three experimental grassland communities. In particular, data from 27 species grown in monoculture showed that species differed in a trait, R *, which is the level to which each species reduced the concentration of soil nitrate, the limiting soil nutrient and which is predicted to be inversely associated with competitive ability for nitrogen (N). In these N-limited habitats, species abundance ranks correlated with their predicted competitive ranks: low R * species, on average dominated. These correlations were significantly different than expected for neutral theory, which assumes the exchangeability of species traits. Additionally, we found that changes in relative abundance after environmental change (N-addition or disturbance) were not neutral but also were significantly associated with R *. 相似文献
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ZHANG Chang-Qin HUANG Cheng-Ling HUANG Jia-Yong WANG Ling-Jun ZHANG Jing-Li SUN Wei-Bang MA Yong-Peng 《Plant Diversity》2015,37(3):357-364
In this study, we investigated Rhododendrons in Baili Rhododendron nature reserve and recorded species and detailed information of their distributions. A total of 33 species belonging to 6 subgenus, 4 sections and 11 subsecions were observed and the altitudes were ranging from 1300m to 1800m. In general, most Rhododendron species grew together in their typical habitats whereas a few species occurred fragmentally. In addition, we evaluated the conservation status of these 33 Rhododendron species. On the basis of available information, we addressed some problems taking into account the population structure and development of tourism, and suggestions regarding conservation and utilization of Rhododendrons were finally proposed. 相似文献