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231.
本文分析、讨论了CIMS环境下,采用独立制造岛生产模式的车间作业计划的调度规则和编制问题在此基础上,给出了一种独立制造岛作业计划的编制方法  相似文献   
232.
The crustaceans of the fresh waters of Bering Island and their link to the fauna of adjacent regions were studied. Based on original data and existing literature, the species composition of Cladocera and Copepoda was described. The compiled list includes 22 species of Cladocera and 30 species of Copepoda. In the original data, 35 species native to the Commander Islands were reported for the first time. Six species were newly reported in the Far East, and two were newly reported in Russia. The ecological peculiarities of several species and some biogeographical features of the freshwater zooplankton of the island are discussed. The main part of the fauna of the island form Holarctic widespread species (64.3%), another slightly smaller group of the fauna is comprised of Palaearctic species (20.1%), and the remainder comprise Nearctic (6.7%) and Beringian species (8.9%). Particular patterns in the distribution of freshwater zooplankton and the factors underlying the occurrence of these species on the island are considered.  相似文献   
233.
《Journal of Natural History》2012,46(39-40):2583-2598
The impact of islanding on the genetics of the dominant species, Niviventer confucianus, was analysed using 13 microsatellite markers. All 16 populations are of high genetic diversity with a total of 134 alleles. The average number of effective alleles (Ne) is 6; the average expected heterozygosity (HE) and polymorphic information content (PIC) are 0.823 and 0.763, respectively. Landscape fragmentation might contribute to weak genetic differentiation among 13 island populations. Values of FST simulated by Structure 2.3.4 implied that the 16 populations could be assigned into three clusters, from which we postulated the possible dispersion history. Pairwise FST tests showed that genetic differences mainly occurred between small island populations and others. Currently, habitat area appears to be the main factor affecting the genetics of Niviventer confucianus, and not the distances between islands. Hence we suggest that more attention should be paid to habitat area in the future.  相似文献   
234.
本研究旨在了解粤东南澳岛近岸海域表层沉积物中总有机碳(TOC)、总氮(TN)和总磷(TP)的分布情况及污染状况,为该海域环境保护和治理提供科学依据。实验以粤东南澳岛近岸海域32个表层沉积物样品为研究对象,分析其TOC、TN和TP的含量及分布特征,采用单因子污染指数法和内梅罗综合污染指数法对TOC、TN和TP的污染程度进行评价,基于表层沉积物中TOC和TN的摩尔比值探讨其有机质的来源,并在此基础上探讨表层沉积物中TOC、TN和TP的富集影响因素。研究结果表明,南澳岛近岸海域表层沉积物中TOC、TN和TP含量分别为0.180%-0.920%、0.006%-0.210%和0.015%-0.059%,表现出南澳岛南北两侧高、东西两侧低,南澳岛以东由岸及海,含量逐渐降低的分布特征;与国内相邻海域相比,南澳岛近岸海域表层沉积物TOC、TN和TP含量处于较低水平。根据TOC和TN摩尔比值推断,南澳岛近岸海域表层沉积物中有机质以海源和陆源混合输入为主。南澳岛近岸海域表层沉积物未受TOC和TP污染,但大部分区域受到TN污染;40.6%的表层沉积物处于较清洁及以上水平,59.4%的表层沉积物为轻度污染到中...  相似文献   
235.
白沙县金波附近的Spirifercf.,subgrandisRotai ,Neospirifersp .,Fuselacf.tornacensis (Koninck) ,Punc tospirifersp .,Mucrospirifersp .,Eumetriacfserpentina (Koninck) ,Palaeochoristiessp .,Megachonetessp .,Pli chonetessp .,Orthotetessp .,Chonetipustulasp .,Marginatiasp .,Curithyrissp .,Rhipidomellasp .是海南岛首次发现的最丰富的杜内早期腕足动物群。据此 ,该地区含化石的原南好组第四段确定为下石炭统岩关阶。该动物群以石燕贝类最繁盛、长身贝类数量少为特征 ,与华南其它地区同期腕足动物群不同  相似文献   
236.
随着海南国际旅游岛战略目标的提出,海南逐渐吸引了世界目光的聚集;同时,因其得天独厚的地理优势、长夏无冬的气候优势,国内帆船帆板运动早在数年前就开始大规模向海南挺进。这就要求海南立足本地区优势,利用帆船帆板运动独特的市场影响力,以及可观的经济效益,来促进海南多元化经济发展,尽快的实现国际旅游岛的建设目标。  相似文献   
237.
El Nio-Southern Oscillation(ENSO)has affected penguins and their habitats in the western Antarctic Peninsula.We used both historical penguin population dynamics data(1980–2012)and sedimentary lipids in penguin droppings(1916–2001)on Ardley Island to examine the responses of the Antarctic ecosystem to ENSO(El Nin o/La Nin a)events.The results showed that during the last 30 years,climate,marine food chain changes,and human activity have significantly affected penguin population sizes on Ardley Island.The Chinstrap(Pygoscelis antarctica)and Ade′lie(P.adeliae)penguin populations showed a good correlation with ENSO events.The Chinstrap penguin population decreased significantly because it was more sensitive to increasing human disturbance(e.g.,scientific activity and tourism)than Ade′lie and Gentoo(P.papua),particularly during the breeding season.Compositional features of n-alkanes in penguin dropping sediments revealed that organic matter came from lower terrestrial plants,bacteria and algae.C23was the main nalkane heavy hydrocarbon indicating mosses and lichens in the penguin’s diet.Variation in the ratio of nC23/nC17was closely correlated with ENSO events.The bacteria intrusion index(ratio of(iC15:0?aC15:0)/nC15:0for fatty acids)reflected significant increases in microorganism activity during several periods in this area.Meanwhile,the CPIA value for fatty acids decreased because micro-organisms contributed light hydrocarbon fatty acids to penguin droppings.Our results showed that the fine structure and molecular indices of fatty acids and n-alkanes in penguin dropping sediments can be used to explain climate-driven microbial processes,and to reveal the important role that microbes and bacteria play in the relatively simple Antarctic ecosystem.  相似文献   
238.
From Martín García Island were collected 975 jumping spiders, from five environments, using beating net and manual sampling methods. Saitis variegatus Mello-Leitão, 1941 was the most abundant (24.62%). The sandy xerophilous forest had the highest species richness (23 morphospecies) and jungle showed the greatest spider abundance (n: 384). The sandy area was the least diverse and the last in relative abundance. Salticids represented 16% of the species recorded from Argentina, and the second largest family registered. The spider fauna found could be similar to that of the Southern Brasilian region, as occurs with scorpions. Two genera and two species are new records for Argentina. In addition, three new species of jumping spiders, as well as the discovery of the unknown male and female of two species, were registered. There was no record of cosmopolitan spiders or those with a large distribution range on the Island.  相似文献   
239.
周浩郎  黎广钊  梁文  王欣 《广西科学》2013,20(3):199-204
根据2007年秋至2008年春间,涠洲岛6条主剖面15条断面的珊瑚和底质覆盖率、珊瑚补充量、死亡指数的一次两阶段的调查数据和同期4个季度月的水环境调查数据,结合以往的研究成果,初步分析了涠洲岛珊瑚健康状况及其影响因子。结果表明,调查断面珊瑚死亡指数平均为40.90%,珊瑚死亡发生于本次调查的两年前;珊瑚有恢复的迹象,但珊瑚补充量小,珊瑚补充量与活珊瑚+死珊瑚覆盖率显著相关(r=0.520,P<0.05);除汞、铅、锌和油类外,涠洲岛珊瑚礁海区水体的理化、生物因子符合一类海水水质标准,大体上呈微营养水平,春季的水体营养指数明显高于其他季节。涠洲岛珊瑚死亡率高和恢复慢,表明珊瑚处于退化中的亚健康状态。  相似文献   
240.
海南岛红树植物的构筑型及其多样性   总被引:4,自引:0,他引:4  
海南岛红树植物的构筑型共拥有 5种模式 ,为已知热带树木构筑型的 2 1% ,其中以阿特廷斯模式(Attims smodel)为主 ,它占据了 2 3种海南红树植物的 6 5 2 1% ,而施奥特模式 (Schoute smodel)则仅为 1种 ,即单种属的水椰。海南红树植物的构筑型与属之间的关系并不完全明确。尽管阿特廷斯模式发生于绝大多数的属 ,并存在于整个生态序列中 ,但劳赫模式Rauh smodel和施奥特模式则多少反映出与特定属种和生境的相关性。而木榄是典型的奥布利维尔模式Aubreville smodel,其分枝存在两种并置方式 ,从而导致两种分枝格局。  相似文献   
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