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101.
为了解常山(Dichroa febrifuga Lour.)现有产区分布并预测新的产区,本文利用中药材产地适宜性分析地理信息系统TCMGIS(Geographic Information System for Traditional Chinese Medicine)对426个常山样品信息进行了适宜生态因子生长范围确认,分析了常山适宜产地空间分布状况。结果显示,常山主要分布于我国温暖湿润的东部季风区,生态相似系数100%区域分布较为集中,总面积达760 640.1 km2,共829个县区,其中广西、云南、广东、湖南分布较多。本研究结果对常山的野生资源保护、人工规范化种植和资源可持续利用具有重要意义。 相似文献
102.
针对我国土壤环境功能分类分区管理的重大需求,本文讨论了土壤环境功能的广义与狭义概念及其对应属性.基于土壤环境质量对功能的约束分析,阐明了其与土壤环境质量区划关系.在比较不同土壤环境功能区划方法与指标基础上,以土壤环境质量适宜性和土壤环境功能分类为依据,构建了土壤环境功能区划指标体系.提出了全国土壤环境功能区划方案,具体归纳了4个一级功能类型,10个二级功能类型,划分为75个土壤环境功能区.根据不同区域的功能分区现状,提出了相应的管理对策,为我国土壤污染防治规划与区域风险管控提供科学依据. 相似文献
103.
The main vegetation types and distributional characteristics in the Qilian Mountain region were studies. It is shown that characteristic of the Vegetation is evidanced by eeo-geography marginal effect and plateau zone law. The vegetation of this region is affected considerably by the vegetation around the Qilian Mountain region, but is advantageous for all kinds of alpine vegetations, and has an evident similarity and an extensive unanimity with those of Qinghai-Xizang Plateau. On the other hand, the vegetation of the area has its specificity difference with the plateau plane. So, the authors consider to classify the Qilian Mountain region as the secondary unit of the Qinghai-Xizang Plateau vegetation region. 相似文献
104.
海南岛花卉生产区划研究 总被引:2,自引:0,他引:2
本研究将海南岛花卉生产划分为4个气候带,8个气候区,并对海南花卉生产布局作了初步探讨,提出建立六类商品花卉生产基地的设想。 相似文献
105.
106.
中国杨树人工林培育技术研究进展 总被引:42,自引:0,他引:42
我国杨树人工林总面积达700万hm2,位居世界第一.发展杨树人工林、满足社会经济发展和环境保护的需要是世界杨树研究的发展趋势.在介绍中国杨树栽培区区划、杨树人工林的主要栽培无性系及其生产力的基础上,总结了近10年来我国杨树在立地质量评价、苗木培育技术、人工林定向培育模式、混交林营造技术、林农复合经营技术、人工林水分和养分管理技术、立地生产力维护和杨树人工林的生态功能等方面的研究进展,讨论了我国杨树人工林的生产潜力、杨树人工林的布局、杨树人工林定向培育及加强杨树人工林的环境功能研究等问题,为我国杨树人工林资源的培育及可持续经营提供参考. 相似文献
107.
基于RS和GIS的长沙市生态功能分区 总被引:12,自引:1,他引:11
提出了基于城市、城郊生态过渡区及其周围自然生态支持系统为统一体的城市生态功能分区思想,并建立了长沙市生态 社会 经济信息系统数据库.通过参数选取与权重确定,进行生态适宜度、生态环境敏感性、生态服务功能重要性与经济社会发展水平分区.依据生态功能的空间异质性和生态功能单元内部均质性,将长沙市划分为5类城市生态功能区:Ⅰ类区占总面积的29.47%;Ⅱ类区占总面积的32.5%;Ⅲ类区占总面积的25.95%;Ⅳ类区占总面积的9.63%;Ⅴ类区占总面积的2.45%.分区结果对长沙市发展有指导意义.该研究方法优点有:制图过程定量化、自动化;可在短期内产生最新专题图产品;结合GPS和RS,可以通过监测区域边界类型的变化,进行生态环境监控,为RS数据实时进入GIS系统提供了途径. 相似文献
108.
The valley in upper reaches of Yellow River is situated in the east of Qinghai, China, between latitude 35b20c~ 36b 25c N and longitude 100b55c~ 102b50c E. This area belongs to the transitional zone of Qingha-i Tibetan Plateau and Loess Plateau at an altitudinal range of 1 780m to 4 969 m. The total area is c113 480 km2. Its climate is continental or plateau- continental one. There are 1 027 species of wild seed plants which belong to 86 families and 404 genera in the area. They are 44195% of the total species, 95156% of the total families and 79153% of the total genera in Qinghai, respectively. The floristic characteristics in wild seed plants for the area are as follows: ( 1) Species and woody ones are richer. ( 2) Species endemic to China also richer, but those endemic to Qinghai are very poor. ( 3) On the level of genera, all the fifteen distribution types in China, especia-lly all the six tropical ones only occur in the area in Qinghai. ( 4) On the analysis of genera and species, the flora is temperate in nature which is dominated by North Temperate elements especially the typical elements from the warm and cold zone of Eurasia, and also with some elements of thewarm, cold warm and alpine types. ( 5) The area is of a marginal one in distribution for many species or genera and especially for many tropical ones, so the flora of the area is clear in maginal nature. ( 6) In floristic geography, it is a converged and transitional region for the Loess Plateau Flora, Hengduan Mountians Flora, Alpine Qingha-i Tibetan Plateau Flora, as well as Qaidam Alpine Desert Flora, so the flora of the area is also conspiarously a transitional one. Therefore, as a marginal region far from the center of Qingha-i Tibetan Plateau and with a transitional flora more or less keeping the floristic nature of plateau and alpine types, so the valley in upper reaches of Yellow River in Qinghai should be a flora still belonging to the Tangute one, although it is weaker in alpine nature but conspicuously much more related to North China one. 相似文献
109.
Ecogeographical regionalization is the basis for spatial differentiation of biodiversity research. In view of the principle of international ecogeographical regionalization, this study has applied multivariate analysis and GIS method and based on some ecogeographical attributes limited to the distribution of plant and vegetation, including climatic factors, such as minimum temperature, mean temperature of the coldest month, mean temperature of the wannest month, annual average temperature, precipitation of the coldest month, precipitation of the wannest month, annual precipitation, CV of annual precipitation, biological factors such as vegetation types, vegetation division types, NPP, fiorisitic types, fauna types, abundance of plant species, genus and endemic genus; soil factors such as soil types, soil pH;topographical factors as longitude, latitude and altitude etc. The ecogeographical regionalization for biodiversity in China was made synthetically by using fuzzy cluster method. Four classes of division were used, viz., biodomain, subbiodomain, biome and bioregion. Five biodomains, seven subbiodomains and eighteen biomes were divided in China as follows: Ⅰ Boreal forest biodomain. Ⅰ A Eurasian boreal forest subbiodomain. Ⅰ A1 Southern Taiga mountain cold-temperate coniferous forest biome; Ⅰ A2 North Asian mixed coniferous-broad-leaved forest biome. Ⅱ Northern steppe and desert biodomain. Ⅱ B Eurasian steppe subbiodomain. Ⅱ BI Inner Asian temperate grass steppe biome; Ⅱ B2 Loess Plateau warm-temperate forest/shmb steppe biome. Ⅱ C Asia-Mrica desert subbiodomain. Ⅱ C1 Mid-Asian temperate desert biome; Ⅱ C2 Mongolian/Inner Asian temperate desert biome. Ⅲ East Asian biodomain. Ⅲ D East Asian deciduous broad-leaved forest subbiodomain. Ⅲ D1 East Asian deciduous broad-leaved forest biome, Ⅲ E East Asian evergreen broad-leaved forest subbiodomain. Ⅲ El East Asian mixed deciduous-evergreen broad-leaved forest biome; Ⅲ E2 East Asian evergreen broad-leaved forest biome; Ⅲ E3 East Asian monsoon evergreen broad-leaved forest biome; Ⅲ FA Western East Asian mountain evergreen broadleaved forest biome. Ⅳ Palaeotropical subdomain. IV F India-Malaysian tropical forest subbiodomain.Ⅳ Fl Northern tropical rain forest/seasonal rain forest biome; Ⅳ F2 Tropical island coral reef vegetation biome. Ⅴ Asian plateau biodomain. Ⅴ G Tibet Plateau subbiodomain. Ⅴ G1 Tibet alpine highcold shrub meadow biome;Ⅴ G2 Tibet alpine high-cold steppe biome; Ⅴ G3 Tibet alpine high-cold desert biome; Ⅴ G4 Tibet alpine temperate steppe biome; Ⅴ G5 Tibet alpine temperate desert biome. 相似文献
110.