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241.
"三言"是中国古代成就最高的白话短篇小说集,关于其中作品的成书时代依然存在着很大的争议和研究空间。《警世通言.陈可常端阳仙化》一文,胡士莹和郑振铎两位先生认为是宋人话本,实则应为明代作品。首先,对前人提出的"宋人话本"说的研究观点提出质疑;其次,根据宋元明时期刑法制度的差异,"沙门岛"领土所属权的变化,证明这篇作品绝非创作于南宋时期;最后,根据"温州府"和"临安府"行政区划的历史沿革,进一步证明这篇小说为明代作品。  相似文献   
242.
《Journal of Natural History》2012,46(10):1247-1258
The seed dispersal system formed by the fleshy-fruited shrub Viburnum tinus L. (Caprifoliaceae) and the bird Erithacus rubecula L. is known to occur in both the Mediterranean basin and the laurel forest of the Canary Islands. The latter is invaded by the ship rat Rattus rattus L. This situation allows (1) the comparison of oceanic island and mainland situations for the bird-plant interaction, and (2) quantification of the possible effects of an invading species on the plant, and thus on the whole seed dispersal system. Fruit removal by birds and rats was studied for V. tinus in a laurel forest of Tenerife during a fruiting season to assess patterns of disperser and predator's use of the plant. Fruits were persistent in time and spontaneous fruit loss rate was low. It was exploited by a reduced frugivorous community. Its fruits were dispersed almost exclusively by E. rubecula at extremely low rates, whereas R. rattus rapidly predated the bulk of the crops. Fruit removal by E. rubecula was influenced by vegetation structure and fruit crop size (higher removal rates from gaps or sparse and low canopy patches, and from larger fruit displays). Fruit predation by R. rattus was not related to microhabitat or individual plant traits. Fruit removal by R. rattus had no apparent influence on the pattern of bird frugivory. However, later in the fruiting season, heavy fruit depletion by rats restrained fruit availability for birds. The mainland (Mediterranean) V. tinus-E. rubecula dispersal system is strikingly different from this island counterpart in: (1) the virtual irrelevance of rodent seed predation, and (2) the comparatively high incidence of bird frugivory by the exclusive seed disperser, E. rubecula.  相似文献   
243.
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   
244.
《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   
245.
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   
246.
海南岛中部山区次生林生态特征研究   总被引:3,自引:2,他引:1  
研究了海南岛中部山区典型的次生林群落特征和优势种枫香的种群结构特征.结果表明:海南岛中部山区的枫香种群所在的群落是演替过渡群落,在群落中枫香占有绝对优势,但随着群落的发展,枫香种群的发育表现出随着次生林年龄的增大而逐渐衰退的典型演替系列过渡种的生物学特性,最终会被群落中的后期演替种所代替.  相似文献   
247.
海南岛七差地区芒果园植被的研究   总被引:3,自引:1,他引:2  
通过对海南岛七差地区芒果园植被的调查研究,结果显示:芒果园植被丰富,共有植物102种、38科、95属,其中以双子叶植物占优势,有72属,单子叶植物次之,有22属;在102种植物中,草本植物有52种,为芒果林下的优势植物种群;植物群落特征为人工植物群落.本文还对芒果园植物的组成、性状、不同生态习性以及多度、盖度和频度进行了分析,并提出合理保护和改良利用芒果园植被的途径  相似文献   
248.
A number of metamorphosed mafic rocks occurred within the Paleozoic strata in the Chenxing and Bangxi regions at the northern side of the Changjiang-Qionghai Fault in Central Hainan Island. These metamorphosed mafic rocks are tholeiites in chemistry. They are characterized by extreme depletion of Th, Nb, Ta and LREEs, resembling the depleted N-type mid-ocean ridge basalts (MORB). Field relations suggest that the protolith of the metamorphosed mafic rocks were likely formed in Paleozoic. These metamorphosed mafic rocks with N-type MORB geochemical features were probably the remnants of the Paleo-Tethys oceanic crust.  相似文献   
249.
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   
250.
海南兴隆热带花园引种工作初报   总被引:1,自引:1,他引:0  
海南兴隆热带花园是一座新建的植物园,在1993~1997年间,进行了大规模的引种驯化工作。据不完全计,已引种植物愈800种,其中棕榈科植物愈200种,中国的珍稀濒危植物50种。  相似文献   
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