中国台湾种子植物区系的性质、特点及其与大陆植物区系的关系

 台湾位于欧亚大陆东南缘的海洋中,地处热带的北部和亚热带的南部,约为21°45′~15°56′N,119°18′~124°34′E,是中国最大的岛屿。它是受季风气候强烈影响的地区之一,热量丰富,雨量充沛,干湿季明显。具有一个非常丰富的岛屿和山区植物区系。就其种子植物而言,约有186科,1201属,3656 种,包括热带属742属,温带属346属。根据台湾植物区系中各大科、主要植物群落优势种和中国特有种的地理分布以及热带属在整个植物区系中的主导地位,台湾地区的植物区系主体具有明显的亚热带性质。中国台湾本地特有种十分丰富,其比例远高于中国特有种的比例。这似乎表明台湾植物区系是一个古老区系在多次地质事件侵袭后又起活化的历史演变的结果。新老成分并存、共同发展是台湾植物区系的重要特点。通过台湾全部属和非特有种在周边地区地理分布的分析,中国台湾植物区系与中国大陆的关系最为密切,是东亚植物区系的重要组成部分,因此在植物分区上应属于泛北极植物区的东亚植物区系。     

我国雾霾形成的机理探析

土壤尘、汽车尾气、燃煤、垃圾燃烧、土木建设工程施工导致的尘埃、生物质燃烧和工业污染等凝结核形成雾霾,我国雾霾具有扩散快和形成较迅速的特点,且增长呈突发性,这些特征多少因水源、土壤及微生物种群受到严重污染,土木。因此,治理雾霾应从水源、农村土壤及工业污染等污染的治理开始,方能标本兼治。     

我国人力资本形成的城乡差别研究

人力资本是通过多种途径的投资所形成的固化在劳动力者身上的素质表现,投资途径决定了人力资本形成机制。农村人力资本在健康、教育、培训和迁移等方面与城市劳动力不同,其人力资本存量较低、投资数额较少、投资途径有限,造成我国城乡人力资本的巨大差距。     

倾听荒漠的声音

在美国．还有比哈佛更难考的学校？来自美国权威的《普林斯顿评论》的数据显示,有一所学院在招考新生时更加苛刻．这就是鲜为人知的美国深泉学院。这所大学十分神秘．几乎与世隔绝．创办至今已近百年．一直特立独行．     

总部经济形成机制的探讨

从总部经济的内涵、形成的动力机制以及总部经济的演进过程三方面来展开对总部经济形成机制的探讨，以求对总部经济有一个较为全面的理解。     

知识来源与形成的探讨

本文对知识来源与形成进行了初步的研究.指出人类知识来源于人类实践活动、人类长期积累的知识以及某些生理性的认知天赋;介绍了知识的现代信息加工模型;阐明了此项研究成果对情报学理论研究的影响.     

试论浙江省森林植物区系

1.  History of development of the forest flora Since the Cenozoic period, the number of forest tree species has steadily  risen.In the course of time, some of the archaic types slowly diminished and perished,and new forms gradually evolved. During the palaeocene, the numher of the gymnospe-rms (with the exception of conifers) and ferns drastically decreased, and that of con-ifers, on the contrary, increased significantly, and meantime the broad-leaved tree spe-cies also appeared. During the Neocene, the angiosperms expanded rapidly and the ve-getation gradually shifted towards the mixed deciduous-evergreen forest. Shortly beforethe Quaternary, there was a series of world-wide climatic fluctuations, as illustrated byprogress and retreat of glaciers, cold-resistant and warm-loving  (thermophilic)  plantsappeared alternately.  In the post-glaciation period, the zonal distribution of forest ve-getation in Zhejiang Province was essentially similar to that of the present time. Exca-vations from Homu-tu, Yu-Yao County,  reveal a luxuriant subtropical forest whichexisted 7000 years ago.      2.  Characteristics of the flora and vegetation      (1)  Of ancient origin, with rich relic elements.      Archaic gymnosperms such as Ginkgo biloba, Amentotaxus argotaenia, Pseudotaxuschienii, Torreya jackii, T. grandis, Taxus chinensis var. mairei, Podocarpus macrophyllus,P. neriifolia, etc, are all found in the Cretaceous deposits.  The occurrence of Ginkgocan be traced hack to the Triassic. Most of the conifers, however, were found in the Ju-rassic, and they have remained to the present time as the main elements of the needle-leaved forests.     Among the primitive angiosperms, Magnoliaceae is represented by 19 species of 8genera; Fagaceae and Lauraceae are the dominant evergreen broad-leaved tree species,the former by 6 genera and 43 species, and the latter by 10 genera and 42 species. Ha-mamelidaceae is represented by 10 genera and 18 species, while Ulmaceae, Tiliaceae, Elae-ocarpaceae, by 21 species of 7 genera, 9 species of 2 genera and 6 species of 2 generarespectively.      (2)  Rich in species and consisting of diverse geographic elements, but domi-nated by the tropical ones.     Throughout Zhejiang Province, there are over 1300 taxa of woody plants (includ-ing varieties and cultivated ones) belonging to 109 families and 423 genera.  Amongthem, 8 families with 25 genera and about 45 species, are gymnosperms, and the rest, 101families with 398 genera and about 1260 species and varieties, are angiosperms.  Themajor angiospermous families include Mognoliaceae,  Fagaceae,  Lauraceae,  Theaceae,Aquifoliaceae and Bambusoideae.  Dominant families and genera are the tropical ones,and next in the order, are the East Asiatic, the E. Asia-N. American, then the tempe-rate, the cosmopolitan, endemic and other elements.      (3)  Rich in endemic species, in monotypic and oligotypic genera.      The endemic species include Abies beshanzuensis, Ostrya rehderiana, Carpinus pu-toensis, Carpinus tientaiensis, Celtis chekiangensis, Calycanthus chinensis, Machilus mi-nutiloba, M. chekiangensis, Semiliquidambar caudata var. cuspidata, Acer aeutum, A.yangjuechi, A. Changhwaense, A. elegantulum, A. pauciflorum, Ilex qinyuanensis, Sty-rax zhejiangensis, Photinia zhejiangensis, Actinidia zhejiangensis, etc.  The monotypicand oligotypic genera are examplified by Ginkgo, Pseudotaxus, Pseudolarix, Fokienia,Cyclocarya, Parakmeria, Pteroceltis, Sargentodoxa, Decaisnea, Aphananthe, Hemiptelea,Zelkova, Fortunearia, Semiliquidambar, Polithyrsis, Ostrya,  Heptacodium,  Tapiscia,Bretschneidera, Choerospondias, Kalopanax, Halesia, Hovenia, Emmenopterys, Eucom-mia, Pileostegia, Platycrater, Alniphyllum, etc.  The majority of the species mentionedabove are rare and precious ones.      (4)  Introduced species gaining importance     Zhejiang Province is mainly situated in  the mid-subtropical zone, and from Yukuan District and the Wenzhou Prefecture southwards it belongs to the evergreen broad-leaved south subtropical forest belt. A number of south subtropical species, such as Eucalyptus spp., Casuarina spp., Acacia mearnsii, have  been successfully introduced into this region.  The introduction of other species, such as Cinnamomum cassia, Grevillea robusta, Michelia alba, Canarium album, Litchi chinensis, Euphoria longan, Kandelia candel, are successful in certain areas.  Small plantations of introduced species from S. W. China e.e. Cinnamomum glanduliferum, C. septentrionale have been established. Inaddition, Metasequoia glyptostroboides, Ulmus pumila, several exotic Pinus species, Carya illinoensis, Robinia pseudoacacia, Amorpha fruficosa, etc. are widely planted throughout Zhejiang Province. In recent years, cold-temperate species such as Chamaecyparis obtusa, Thuja standishii, Thuja occidentalis, Abies firma have been introduced and planted in the mountainous areas.  The forest flora of the province is thus being further enriched.      3.  Geographical analysis of the forest flora      (1)  The south part of Zhejiang lies in the transitional belt between the East andSouth China Floristic Regions, its east part being on the north margin of the SouthChina Floristic Region, and its west part on the south margin of the East China Floristic Region.      (2)  The north part of the province is weakly influenced by the temperate elements, but the influence may extend to the central part of this province as the elevationthere is higher.      (3)  Diverse floristic elements such as those belonging to Japan, Taiwan (China),C. China and S. W. China regions also occur in the province, especially in its westernand eastern parts.     

我国商品房价格形成的主要因素及形成机制分析

基于我国商品房价格的现状,对地价、投资额、需求及政府政策等影响房地产价格形成的主要因素进行了分析,在此基础上进一步对造成高房价的根本原因进行了探析,并最终有针对性地提出抑制高房价的政策建议。     

舟山群岛植物区系地理的数值研究

本文根据对舟山群岛种子植物348个种(及种以下分类单位)在18个地理单位的分布状况进行计算机聚类分析和主成分分析(PCA),表明了该群岛与我国大陆的浙江和江苏植物区系有着密切的亲缘关系和相似性;与日本和我国台湾植物区系的联系则不如一般所认为的那样接近,当然,仍有不少十分有意义的连锁植物存在于三者之间。    舟山群岛在植物区系区划上应为中亚热带北部亚地带,区系特点之一是岛屿植物较发达,而山地森林区系则与我国南方植物区系相接近。