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341.
This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP)in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorphic units and geophysical conditions-constraints or advantages. Additionally, it selects some indicators, according to the availability in acquiring and processing their quantitative data, to analyze the canonical correlations between the typical conversion of grassland and geophysical conditions. The preliminary study indicates that the physical conditions are of great advantages to the development of grassland. There exists significant correlation between land use change and some geophysical conditions.  相似文献   
342.
According to archaeological data from about sixty samples the relative stability of physical and human geographical environment in the tropical zone of China is discussed in this paper. Because of the superior natural environment, sufficient food resources and a sparse population resulting in the absence of social requirement to transform the productive forces, the advancement of economy and society was stagnated during prehistorical period in China's tropics. Compared with northern China, the appearance of ground stone tool stagnated about 3,000 years, the beginning of Bronze Age, about 1,000 years, and the agriculture, 2,500-3,000 years. The no ceramics age continued till the early Neolithic Age and the appearance of colour or white ceramics was 2,000 years later than that in northern China. The life form of migration to gather and to hunt continued till the middle Neolithic Age, and the fixed settlement based on agriculture 1,000-2,000 years stagnated. The clan commune just appeared at the end of the Neolithic Age which was 2,000-3,000 years later than that in northern China.  相似文献   
343.
344.
中国劳动力资源配置区域差异分析   总被引:3,自引:0,他引:3  
区域经济发展和经济结构调整的关键在于劳动力资源的合理配置。中国各省市区劳动力资源的产业和行业分布具有显著的地域差异,在空间分布上东、中、西部具有差异,西部地区的西南和西北地区也存在差别,这种规律反映了我国经济发展和产业结构高级化的区域差异。根据劳动力行业配置的区位熵排序结果,将各省市区分成4种类型:大都市型、沿海高工业化水平型、中等工业化水平型、中下等工业化水平型。这些类型具有自东向西有规律性的分布,与我国的经济发展格局和工业化水平的东西差异相应。  相似文献   
345.
川西北高原若尔盖草地沙化及湿地萎缩动态遥感监测   总被引:61,自引:2,他引:61  
应用卫星遥感资料(MSS、TM及spot)对川西北高原若尔盖草地沙化及湿地萎缩的动态监测发现,自1966年至2000年的34年间,草地沙化面积增加307.7%,达到36760.9hm^2,占区域总面积的7.25%,平均每年扩大草地沙化面积816.0hm^2,年均递增率达4.22%。到2000年止,区域内有沙地5083.9hm^2,沙化草地31677.0hm^2。自1985~2000年的15a间,区内17个湖泊面积缩小842.0hm^2,减幅达38.9%,平均每年减少56.1hm^2,年均递减速度达3.34%,该区目前其余11个湖泊总面积仅为1323.1hm^2,只有15年前的61.1%。  相似文献   
346.
中国加入WTO对长江三角洲地区产业发展的影响   总被引:4,自引:0,他引:4  
加入WTO对中国的经济运行环境和区域经济走势将带来深远的影响。长江三角洲地区是我国最有潜力和条件参与较高层次国际竞争的地区之一,但是该地区计划经济体制的影响较深,区域经济发展的问题和制约因素突出。因此,利用新的视角开展中国加入WTO对长江三角洲地区产业发展的影响的综合研究,对我国21世纪地区经济的发展和走向具有重要的指示意义。本文通过对长江三角洲地区产业发展的现状和主要问题作了探讨,并在此基础上,对中国加入WTO对长江三角洲地区产业的冲击力进行了评估和判断。本文认为,为应对中国加入WT0后所带来的冲击,抓住发展机遇,提高区域整体竞争力,长江三角洲地区各城市有必要形成共识,规范和统一地方政府行为,在充分发挥市场机制作用的条件下,对区域产业调控机制和模式作重新构思,以进行区域产业分工体系和区域产业分布格局跨省市、全区域的合作与协同调整。  相似文献   
347.
Reviewing some important German scientists who have developed climatic regionalization schemes either on a global or Chinese scale, their various definitions of the tropical climate characteristics in China are discussed and compared with Huang Bingwei's climate classification scheme and the identification of the tropical climate therein. It can be seen that, due to different methodological approaches of the climatic regionalization schemes, the definitions of the tropics vary and hence also their spatial distribution in China. However, it is found that the tropical climate type occupies only a peripheral part of southern China, though it firmly represents a distinctive type of climate that is supsequently associated with a great economic importance for China. As such, the tropical climate type was mostly identified with its agro-climatological significance, that is by giving favourable growing conditions all-year round for perennial crops with a great heat demand. Tropical climate is, hence, conventionally regarded to be governed by all-year round summer conditions "where winter never comes".  相似文献   
348.
Studies indicate that the climate has experienced a dramatic change in the Heihe River Basin with scope of temperature rise reaching 0.5-1.1oC in the 1990s compared to the mean value of the period 1960-1990, precipitation increased 18.5 mm in the 1990s compared to the 1950s, and 6.5 mm in the 1990s compared to the mean value of the period 1960-1990, water resources decreased 2.6×108 m3 in the 1990s compared to the 1950s, and 0.4×108 m3 in the 1990s compared to the mean value of the period 1960-1990. These changes have exerted a greater effect on the local environment and socio-economy, and also made the condition worsening in water resources utilizations in the Heihe Rver Basin.  相似文献   
349.
Influence of Arctic Oscillation on winter climate over China   总被引:2,自引:0,他引:2  
In this study the relationship between the Arctic Oscillation (AO) and climate in China in boreal winter are investigated. Correlation analysis for the last 41 years shows that the winter temperature and precipitation in China change in phase with AO. High positive correlation (>0.4) between temperature and AO appears in the northern China. High correlation coefficients between precipitation and AO cover the southern China (close to the South China Sea) and the central China (between 30o-40oN and east of ~100oE), with the values varying between +0.3 and +0.4. It is found that during the past several decades the precipitation was strongly affected by AO, but for the temperature the Siberian High plays a more important role. At the interdecadal time scale the AO has significant influence on both temperature and precipitation. Multivariate regression analysis demonstrates that AO and the Siberian High related variance in temperature and precipitation is 35% and 11% respectively. For precipitation, however the portion is rather low, implying that some other factors may be responsible for the changes in precipitation, in addition to AO and the Siberian High.  相似文献   
350.
ABSTRACT. The Shimentai Nature Reserve in Yingde County, Guangdong Province, China, established recently in a subtropical upland forest area, has served for ages as an essential and customary source of livelihood for local people. Assessment of forest usage indicates heavy reliance by villagers on its diversified biotic resources. This forest dependence, associated with socioeconomic factors such as distance from village, ethnic origin, out‐migration of rural youngsters, and a local tradition of conservation, is unlikely to decline in the near future. The reserve management recognizes the need to address the livelihood issues of local people and to win local support. A pragmatic adherence to provincial and higher‐level policies that exclude forest‐tapping activities could lead to more people‐versus‐park conflicts, which would dilute fundamental conservation objectives. A more enlightened and localized approach that nurtures a synergy between limited forest use and conservation while helping to develop new income sources could furnish workable alternatives.  相似文献   
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