Study on change of weather and climate extremes has become an important aspect in modern climate change research. Based on the daily surface air temperature data from 200 stations and daily precipitation data from 739 stations during the second half of the 20th century, schemes for analyzing climate extremes were designed mainly according to percentiles of a non-parametric distribution and the gross errors in the daily data were removed based on a newly designed quality control procedure. The spatial and temporal characteristics of change of climate extremes over northern China were studied. The main conclusions are summarized as follows: 1) The number of days with maximum temperatures over 35oC decreased slightly. The decreasing trends are obvious in the North China Plain and the Hexi Corridor. However, since the 1990s, the extreme hot days increased greatly. Meanwhile, the frost days decreased significantly in northern China, especially in the eastern part of northern China and Xinjiang Uygur Autonomous Region. Increase trends were found for the 95th percentiles of daily maximum temperatures except in the southern part of North China, while obvious decrease trends were found for the 5th percentiles of daily minimum temperatures. 2) The extreme intense precipitation events obviously increased in much of northwestern China but decreased in the eastern part of northeastern China and most parts of North China. The number of heavy rain days increased in eastern Inner Mongolia and eastern Northeast China, but obviously decreased in the Northeast China Plain and North China.
Cultivated land, different from other resources, is fundamental to the sustainable development of Chinese agriculture, society and economy. Market mechanism inevitably drives cultivated land into industrial and urban uses. Rapid industrialization and urbanization lead the scarce cultivated land resources to more crises. So market is a failure to allocate this kind of resource which can be regarded as common property in a certain sense. Government intervention is necessary for optimization allocation of cultivated land. Current policy of macro-administration for cultivated land conservation is oriented to total quantitative control. Every province is demanded that the total number of cultivated land remains not decreased. This policy is difficult for practicing because it does not consider various situations in different regions. For example, in eastern provinces where rapid industrialization and urbanization is proceeding and reserved arable land is scarce, the total number of cultivated land will inevitably decrease unless at the cost of lowering the economic growth. Therefore, it is necessary to innovate the policy of cultivated land resources conservation and utilization. The authors put forward the concept of minimum area per capita of cultivated land (MAPCCL) as a new insight into the optimization of land resource allocation for policy making. MAPCCL can be defined as the minimum number of cultivated land that can meet the needs of food consumption under certain food self-sufficient rate and land productivity. PICL provides a threshold of cultivated land conservation. If K<1, some cultivated land may be conversed into urban and industrial uses and planting structure may be adjusted for more cash crops. If K>1, cultivated land should not be conversed into other uses or land quality and productivity should be enhanced by means of increasing input and technological innovation.
From the essential meaning of urbanization, this paper establishes a comprehensive evaluation index system, including four aspects changing: population, economy, society and land. Based on the method of entropy, the measure and evolution of China's urbanization are analyzed since 1981. The results show that China's comprehensive urbanization level continues improving. Economic growth and geographical landscape are the main features of rapid evolution of urbanization, followed by the population urbanization, and the medical care level of social urbanization is the least advanced. The evolution of all the four subsystems has unique characteristics. The analysis of multiple regression model shows that the driving factors have been diversified. The market force is the most powerful driving force of China's urbanization, followed by intrinsic force, administration force, exterior force. From different stages of urbanization, the effects of market force, exterior force and the administration force on urbanization are increasing, while intrinsic force is decreasing. China's urbanization is the main endogenous process, hence more policies should be formulated to strengthen the market economy reform and coordinate urban and rural development.
Recently, many sorts of index models have been widely adopted in the analysis of land use change in China. And they do play an important role in summarizing the rule of regional land use changes. However, according to the present research papers, there are some confusions and misuses in their applications, which root in faultiness, abnormity and misunderstanding of the indices or index calculation. By detailed exploration of the indices embedded in research materials, three classifications are identified on the basis of their application purposes: the change of regional land resources (change rate index and level change index), the direction of land use change (transition matrix and flow direction rate) and the spatial pattern of land use change (dynamic degree, relative change rate, adjacency degree, barycenter, frequency degree and importance degree). Then all the indices listed above are discussed under the purposed framework, including their concepts, calculation methods, application fields, misuses, and some application suggestions. This paper also gives a remark in the end that the research of land use change needs new breakthroughs in both theory and methodology. Index method is only a simple kind with limited functions, and much more efforts should be devoted to integrative, predictive methods in the coming days.
This paper uses the first-hand data of 1987 and 1999 to analyze the spatial evolvement of Guilin's domestic tourist origins of the years concerned. It is revealed that the number of tourists increased steadily after 1980, while the 1980s were the golden era of Guilin's domestic tourism development. The spatial concentration index (SCI) of tourist origins indicates a drop of 12% from 1987's 43.50 to 1999's 38.27, which means that after 12 years, Guilin's tourist origins have expanded and have become more stable, while the spatial distribution has become less concentrated. Taking into account the increment percentage of tourists from each tourist origin, the paper develops a formula to calculate the attraction radius (AR) of tourist destination (TD) revised from the formula of standard distance given by Stephen Smith (1989). Using the railway distance between Guilin and the capital city of each province as the mean of the traveling distance from each region, the paper shows that Guilin's AR raised by 40.84% from 1987's 568.12 km to 1999's 800.14 km. From the view of macroeconomics, we consider the following as the possible reasons for the drop of Guilin's SCI and the rise of its AR: firstly, as a long-established tourist destination, Guilin's word-of-mouth reputation played a very important role in attracting tourists. Secondly, the rapid increase of living standard and the practice of long weekends/vacations has brought China to a golden era of domestic tourism where more people travel more frequently than before. Thirdly, the social and economic development in areas such as Beijing, Shanghai, Jiangsu, Shandong, has made it possible for Guilin to attract more tourists from them. As a result, the spatial distribution of Guilin's domestic tourists origins has developed a pattern that is different from the law of distance decay. Fourthly, the degree of increment in a tourist origin is mainly due to two factors--spatial distance and the level of economic development. A place near a tourist destination may have a low increment of market share because of its low level of economic development. A place far from a tourist destination may have a high increment of market share because of its high level of economic development. The intervening opportunity is probably the fundamental factor to analyze this phenomenon. According to the conclusion, the paper proposes some guidelines for Guilin's tourism marketing. Finally, the paper discusses briefly the difference of evolvement in the domestic tourist markets between Guilin and Huangshan.
Based on the theory and method of ecological footprint, combined with the ecological consumption and its structural character of tourist, the paper, taking the Huangshan City as an example, calculates and analyses the touristic ecological footprint and its efficiency of Huangshan City in 2002. Six characteristics have been summarized: (1) The touristic ecological footprint of Huangshan City is 0.106 hm2 per capita in 2002. In comparison, the fossil energy land is about 88.23% of this footprint, tourist transportation and food are the main constitutes of the total footprint, about 55.67% and 33.90%. (2) The ecological deficit of Huangshan City is 0.219 hm2 per capita in 2002. About 48.40% of the ecological deficit is a result of touristic ecological footprint. (3) Extrapolating the footprint of a tourist to Huangshan City (3.13 days) to 1 year, results in an area of 12.36 hm2 per capita in 2002, almost 9 times that of the average footprints of citizens of Huangshan City. (4) In Huangshan City, the average tourist output of 1 hm2 ecological footprint is US$684, 1.17 times the average output of the Huangshan City' citizens ecological footprint, 61.84% that of the world. (5) Dimensions of tourist flows, tourist consumption level and model, tourist spatial behavior, the policy and stratagem of the tourist destination are the key factors to affect the size of touristic ecological footprint. (6) The shift of TEF among regions will result in shift and diffusibility of tourist ecological responsibility, ecological influence and ecological stress among regions in the world, and tourism development may have profound impacts on global environments.