许昌地区种子植物区系分析     

姜罡丞  董东平 《许昌学院学报》2005,24(5):135-139

许昌地区地处伏牛山余脉向豫东平原过渡地带，属暖温带区域．根据吴征锰教授对中国种子植物分布区类型的划分，对本区种子植物的分布区类型的研究发现，本区种子植物各属共有15种分布区类型和15种变型；对其种子植物区系的属组成的初步分析发现，该区植物区系有以下特征：1）以温带性质为主兼有一定热带成分，显示出暖温带与北亚热带过渡交替的特征；2）区系地理成分多样，与其他植物区系问联系广泛；3）植物区系起源古老，存在一些中国特有、残遗属．  相似文献   

WTO规则与中国野生植物资源保护     

宋才发 《青海师范大学学报(哲学社会科学版)》2004,(1):11-14

中国既是野生植物资源最丰富的国家之一,又是《生物多样性公约》的签字国,国家有关部门已经开始注意到了生物多样性的保护和生态安全保障。我国对植物新品种保护作出了明确的法律规定。必须依法保护农业野生植物,依法引进新鲜植物物种。同时又必须深刻认识外来物种入侵的威胁和危害,对外来入侵物种的危害必须依法治理。  相似文献   

广西植被和植物区系基本特征Ⅰ．自然条件及植物区系的组成   总被引：2，自引：0，他引：2  

苏志尧  廖文波  张宏达  中山大学生命科学学院 《中山大学学报论丛》1996,(2)

对广西进行了详细的植物区系调查和植物区系名录整理．结果表明，广西植物区系共含野生维管植物２７５科、１５７５属、６８２６种．其中蕨类植物５４科、１２５属、５３２种；裸子植物７科、１３属、４８种；被子植物２１４科、１４３７属、６２４６种．本文简述了与该地区植物区系有关的自然条件，分析了该地区的植被特征，对区系的组成特点进行了初步的统计分析  相似文献   

白洋淀水生植物区系初步分析   总被引：1，自引：0，他引：1  

陈耀东 《中国科学院研究生院学报》1987,25(2):106-113

The Baiyandian Lake lies at 115°56′ E. and 38°55′ N.  It is about 8 m above sea level, with an area about 312 square km.  There are abundant aquatic plants here, inc- luding flowering plants of 30 families, 46 genera, 66 species and 3 varieties besides one in- troduced species.  32 species are erect ones covering about 48.5% of the total number of species in this lake, 20 are submerged ones, about 30.3%, 9 are leaf-floating ones, about 13.6% and 5 are floating ones, 7.6%.  The soil at the bed of the lake is very fertile and the depth is appro- priate, favouring various plants.  The coverage is large, sometimes it may reach 100%, for example, in communities of Phragmites communis, Hydrilla verticillata,  Hydrocharis dubis, Trapa bicornis, etc. Although the Baiyandian Lake is located in the temperate zone, the floristic elements are complex.  There are tropic-subtropic elements and elements of high-frigid zone as well.  When compared respectively with the floras of the Lakes Jingbo Lake, Honghu Lake and Lugu Lake, the flora of this lake is found more similar to that of subtropic Honghu Lake than to those of the other lakes, which shows that it hase a character transitional between the south and the north in China.  Further studies of the floristic relationships are needed in order to exploit and use the resources of the aquatic plants in this lake.  相似文献   

西藏蔷薇科植物的区系特点和地理分布     

俞德浚  陆玲娣  谷粹芝 《中国科学院研究生院学报》1984,22(5):351-359

The Rosaceae is one of the five largest families of Xizang flora,  consisting of 30 genera with 242 species,  the total number of species is slightly less than those of Compositae,  Graminae,  Leguminosae and Ericaceae in Xizang,  amounting to 62.5% of the total number of genera and 28% of the total number of species of the rosaceous flora in China.       The four subfamilies of Rosaceae including primitive,  intermediate and advanced groups have been found in Xizang.  These groups consist of 11 types of floristic ele- ments,  i.e. 4 genera belong to cosmopolitan,  9 genera belong to North Temperate,  3,  E. Asian-N.  American,  3 Sino-Himalayan,  3 Sino-Japanesa,  2 Old World Temperate,  1 Temperate Asian,  2 Mediterranean-W. and O. Asian,  1 C. Asian,  I Tropical Asian and 1 endemic to China. It is obvious that Rosaceae in Xizang comprises holarctic,  Ancient Me- diterranean and paleotropical elements,  among which the temperate components are the most dominant.  The characteristics of the floristic composition of Rosaceae in Xizang may be summarized as follows:       (1) Xizang abounds in both genera and species of the family which are diverse in forms,  including the primitive,  intermediate and advanced groups, (2) The geographi- cal elements are rather complex,  mostly belonging to the temperate,  among which the Sino- Himalayan components and the elements endemic to China are dominant, (3) The proportion of plants endemic to China and distributed in Xizang is much higher than those endemic to Xizang itself,  but there exist newly arisen species and infraspecific forms or varieties which show that the speciation is apparently still active in Xizang. The rosaceous flora of Xizang is a combination of old and new floristic elements,  based on the old floristic components,  affected by the upheaval of the Himalayas,  the differen- tiation and speciation have been taking place in the long history.       The geographical distribution of Rosaceae in Xizang may be divided into 5 regions, i.e. the northeastern,  southeastern,  southern,  northwestern and northern.  The rosaceous plants are most abundant in the southeastern area,  next in southern area,  fewer in the northeastern and very rare in the northwestern and northern regions.  The general ten- dency of the distribution of Rosaceae in Xizang is that the number of species gradually decreases from the southeast to the northwest and the habit gradually changes from trees,  shrubs and herbaceous plants in the southeast to cushion-like scrubs and dwarf perennial herbs in the northwest.  These facts clearly show that the uplift of the Hi- malayas has deeply affected the phytogeographical distribution of Xizang Rosaceae.       The rosaceous flora of Xizang has close relationships with those of the adjoring regions,  i.e. Yunnan and Sichuan.  Besides,  it is connected with floras of Nepal,  Sikkim, Bhutan nothern Buram and nothern India,  but silghtly influenced by the Ancient Medi- terranean flora.  相似文献   

论汉字义符与物类的关系   总被引：1，自引：1，他引：0  

陈枫 《陕西师范大学学报(哲学社会科学版)》2003,32(6):45-49

义符的表意系统根据事物的性质、状态、特征、功能等关系而形成。义符表意范畴的大小和划分,与义符代表的事物有密切的关系。义符不等同于事物的类别符号。  相似文献   

全面落实科学发展观推动野生动植物保护事业在社会主义新农村建设中发挥应有作用     

斯萍 《高校教育管理》2006,(3)

党的十六届五中全会做出的推进社会主义新农村建设的重大战略决策,是全面落实科学发展观的客观要求和必然选择。我国的野生动植物资源和培育利用产业主要分布在广大农村地区,处理好野生动植物保护、利用和发展的关系,有助于推动农村经济、政治和文化各项事业发展。因此,要以科学发展观为统领,大力促进野生动植物保护事业全面、协调、可持续发展,为社会主义新农村建设做出应有的贡献。  相似文献   

The boyhood of Birbal Sahni     

Sahni  Ashok 《Resonance》2004,9(4):42-49

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芽孢杆菌对罗非鱼土池水质和浮游生物的影响   总被引：1，自引：0，他引：1  

林东年  叶宁  周志锋 《茂名学院学报》2006,16(4):18-21,26

在罗非鱼池塘养殖过程中,投放以芽孢杆菌为主导菌的微生物复合制剂后,研究池塘中水质、异养细菌总数、浮游植物和浮游动物的组成和数量、罗非鱼体重和体长的变化情况。实验表明:鱼池投放菌剂后,能改善水质条件,分解有机质,降低氨氮,增加无机盐;芽孢杆菌可以在实验水体中顺利增殖成为优势菌,但不能长久维持优势地位;菌剂有促进罗非鱼生长的作用,罗非鱼在体重和体长方面都有增长优势。  相似文献   

鲁中南地区维管植物区系分析     

全先庆  李春海 《临沂师范学院学报》2002,24(6):43-46

鲁中南地区有维管植物126科、479属、1087种，通过各方面的分析，表明该植物区系具有明显的温带性质。  相似文献