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101.
管耀宗  张继国  朱永忠 《水文》2015,35(5):11-14
充分挖掘降雨变量语法信息,利用基于差异序列信息熵测度理论的遗传算法聚类分析方法,对淮河流域蚌埠站以上区域99个雨量站进行了分区研究。根据各子区域内雨量站降雨序列差异测度得到最优分区,从而使得降雨信息在区域内具有较大的同质性。最后,以插值精度为标准,将不分区的情况为参照对象,对2、4、8三种分区结果进行校验,结果显示,相对于不分区,分区明显提升了降雨插值的精度。  相似文献   
102.
http://www.sciencedirect.com/science/article/pii/S1674987114000668   总被引:1,自引:0,他引:1  
Microbial diversity in the hydrate-containing (sites SH3B and SH7B) and-free (sites SH1B, SH5B, SH5C) sediments collected from the Shenhu area of the South China Sea (SCS) was investigated using 16S rR...  相似文献   
103.
新文化地理学的理论统一性与话题多样性   总被引:14,自引:6,他引:8  
新文化地理学起源于20世纪80年代,是对传统文化地理学研究范式的激进反思甚至颠覆。首先,新文化地理学具有理论基础的统一性。其反对伯克利学派"超有机体"的文化观,认为"文化"并非具象的"物体",而是在特定的社会情景或社会关系之下由社会群体自下而上地建构或生产的。自然、景观、地方、空间等地理学要素也并非"文化"被动的表达或容器,而是建构意义与价值系统的关键维度。其次,新文化地理学具有研究话题的多样性。这种多样性不应该被简单理解为研究视角的分散性或破碎性,而是新文化地理学的文化观带来的必然结果。新文化地理学关注草根群体自下而上的文化实践、不同群体与不同尺度的文化事项、以及瞬息万变的日常生活经验。因此,这极大地拓展了其研究话题的广度。目前,中国地理学中有关文化的研究还处在比较边缘化的位置,但现代中国社会的高速变迁迫切地要求文化地理学者从文化的社会性与空间性出发,探讨社会成员赋予自然、景观、地方、空间等地理学要素的文化意义,以及文化这一维度在经济地理学、城市地理学等研究中的重要作用。  相似文献   
104.
The ichthyofauna of the intermittently open Shellharbour Lagoon in southeastern Australia was sampled over 14 months to investigate factors influencing species composition. Zostera capricorni and bare sand habitats were sampled every two months with a fine-mesh seine. Of the 10 277 fish caught representing 19 families and 27 species, the most numerically dominant species were Pseudogobius olorum and Pseudomugil signifer. The most abundant economically important species were Acanthopagrus australis, Mugil cephalus and Myxus elongatus. Mean number of fish and species was significantly higher over Zostera than bare sand during months immediately after the estuary opened when juvenile marine fishes recruited, demonstrating the estuary's nursery function. In contrast to other intermittently open estuaries in Australia and South Africa, Shellharbour Lagoon's fish assemblage appears resilient to perturbation and does not undergo distinct seasonal variations. This may be a result of the estuary's short open phases providing less opportunity for marine fishes to enter. Perhaps more importantly, the less dramatic fluctuations in salinity between open and closed phases maintains salinity at a level intermediate of the tolerances of both marine and estuarine fishes.  相似文献   
105.
The genetic diversity of both wild and reared Pseudosciaena crocea (Richardson) col-lected from Guan-Jing-Yang in Ningde, China in May 1999 was investigated by random amplified poly-morphic DNA (RAPD) in the present study. The polymorphism and mean difference of the wild popula-tion as revealed by RAPD were 18.9% and 0.0960 respectively, and those of the reared stocks were rel-atively lower, with 16.7% in polymorphism and 0.0747 in mean difference. The genetic distance be-tween the two stocks was 0.0041. From the comprehensive investigation, the main reasons for the loss of genetic diversity were probably overilshing, small number of parents as broodstocks and the debatable arti-ficial ranching. Results from this study also showed that the large yellow croaker populations distributed along Fujian coastal waters including Guan-Jing-Yang still potentially wide genetic variability. It is sug-gested that genetic management and prevention should be scientifically conducted in order to maintain and improve the genetic diversity of the P. crocea population.  相似文献   
106.
河南省卢氏-栾川地区位于华北陆块南缘与秦岭造山带的衔接部位,是中国重要的钼、钨、铅、锌多金属成矿区。通过控矿地质条件与成矿环境多样性分析,将研究区铅锌矿划分为3种成因类型:岩浆热液交代型铅锌矿床、MVT型铅锌矿床和SEDEX型铅锌矿床。在此基础上,利用“成矿专属性”和“成矿多样性”相结合的找矿思路,对矿区不同类型矿床成矿进行远景评价,指出具有良好的找矿前景。  相似文献   
107.
Ethnic coexistence in a pluralistic campus environment   总被引:1,自引:0,他引:1  
In Malaysia, ethnic segregation seems to have grown more and more pronounced at all levels of education, which may have in the main contributed to increasing occupational segregation by ethnicity when the graduates left to join the job market. Such trends may be disturbing given the effort the country has put in to promote interethnic understanding and reduce interethnic economic disparity since 1970. By critically investigating the dynamics of ethnic coexistence in the microcosm of the university campus environment, this paper provides statistical evidence to show how far the country has progressed in terms of ethnic relations since the watershed events of May 13, 1969; to what extent Malaysian multiethnic society is different now compared to the unmistakable racial “corporateness” and interethnic “separateness” that Furnivall observed in his classic study of 1948; and in what ways ethnic relations have been reshaped by three decades of affirmative action policies and the form of ethnic democracy adapted for this unique society.
Emile Kok-Kheng YeohEmail:
  相似文献   
108.
为了解西沙群岛珊瑚礁海域浮游动物的群落特征, 于2015年5月末至7月初在西沙群岛8个岛礁(七连屿、永兴岛和东岛3个岛屿以及浪花礁、盘石屿、玉琢礁、华光礁和北礁5个环礁)进行了浮游动物采样, 分析了浮游动物的多样性、丰度和群落结构特征, 并比较了5个环礁潟湖内和向海礁坡区浮游动物群落组成的差异。调查海域共鉴定浮游动物180种(包括浮游幼虫13个类群), 其中桡足类最多, 达83种, 其次是水母类(38种)、浮游软体类(14种)、毛颚类(11种)和浮游被囊类(7种); 浮游动物平均丰度为256.4±117.8个·m-3, 桡足类占总丰度的51.08%, 其次是浮游幼虫(16.30%)、浮游被囊类(13.22%)和毛颚类(7.70%)。浮游动物种数、多样性和均匀度指数、丰度在岛屿和环礁之间以及环礁的潟湖区和向海礁坡区均存在差异; 浮游动物多样性和丰度在东岛、玉琢礁和华光礁较高, 而在七连屿和北礁较低; 5个环礁向海礁坡区的浮游动物多样性和丰度皆高于潟湖区的。多元统计分析结果表明调查岛礁的浮游动物可划分两个聚群(相似水平85%); 岛屿近岸及环礁的潟湖群落(Ⅰ)和岛屿远岸及环礁的向海礁坡群落(Ⅱ); 两个聚群浮游动物组成差异较显著(r=0.832, p<0.001); 前者的种数、多样性指数、总丰度和主要浮游动物类群如桡足类、毛颚类和浮游幼虫的丰度显著低于后者。环礁潟湖区和向海礁坡区的空间异质性和生态环境差异可能是导致浮游动物群落结构呈现不同特征的主要因素。  相似文献   
109.
《The Journal of geography》2012,111(5):152-157
Abstract

A Southern Poverty Law Center grant enabled purchasing dolls representing children of different races, ethnicity, and condition of disability. The teacher used these with other materials to sensitize kindergarten children to human differences. She directed them to cut pictures from National Geographic Magazine showing people who are “somehow different/' Responses from children were classified. Nine commented on adornment, three on household setting, two on occupation, and one on race. Little research exists on teaching geography to kindergarteners except on the ability to read maps. The authors contend that kindergarteners are quite ready to learn about regional differences among human populations.  相似文献   
110.
Two typical provincial capitals (Nanjing and Zhengzhou) and two counties (Rugao and Yuanyang) in east (Jiangsu Province) and central (Henan Province) China were chosen respectively as the developed and less developed comparative cases for pedodiversity and land use diversity correlative analysis by borrowing the recently better developed pedodiversity methodology. Land use classification was worked out using remote sensing images in three different periods (1986-1988, 2000-2001 and 2004-2006) for these studied case areas before the calculation of the constituent diversity index and spatial distribution diversity index modified after Shannon entropy in 2 km×2 km grid scale of the soil and land use pattern were conducted and then a connection index was proposed to evaluate the relationship between soil and land use diversity. Results show that during the years from 1986 to 2006, the composition and spatial distribution of regional land use pattern had changed greatly. The agricultural land area of all the studied case areas decreased obviously in which Nanjing has the highest decrement of 895.98 km 2 mainly into urban use while the other land use type area changes show the same trend. The connection index of four typical soil family types and typical urban land use types, i.e., urban construction land, transportation land and industrial and mining area all increased in this period. In the studied case areas, there is the highest soil constituent diversity in Zhengzhou at 0.779 while the simplest soil constituent diversity in Rugao at 0.582. Meanwhile we have higher land use diversity in the more urbanized Jiangsu Province than Henan Province, Nanjing is ranking the first that has been getting higher and higher in the three periods at 0.366 in 1986-1988, 0.483 in 2000-2001 and 0.545 in 2004-2006. Finally, the connection index figures to evaluate the relationship between soil and land use diversity of the studied areas were compared to show the similar phenomenon that this figure grows fastest in Nanjing followed by Zhengzhou and other places.  相似文献   
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