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  • 2002 Volume 22 Issue 2
    Published: 20 March 2002
      

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  • GU Chao-lin, SHI Ai-hua, WANG En-ru
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    August L sch, a famous economist, attached much importance to the relationship of space and location. Based on the traditional location theory from German, he engaged in the research of the matching of economy and space, and then established the theory of economic landscape. He had hoped that his own research would form a new field-space economy and brought the reconstruction to the economy itself. But in fact, the theory of economic landscape had not much effect on the economy. On the contrary, his famous book, The Economics of Location, did tremendous contribution to the development of economic geography and the gestation of region science between the 1850s and the 1860s. With the trend of economic globalization, the western economists have been interested in geography again in recent years, of which the leaders are Krugman, Porter, Arthur, etc. So "the new economic geography" or "the geographical economics" emerged. The paper introduces in detail the two major themes of "the new economic geography": the spatial agglomeration of economic activity and the dynamics of regional growth convergence, then points out the deficiences in "the new economic geography". In the end the paper emphasized that geography and economics should construct their new alliance based on the same goal and philosophical foundation.
  • LU Yu-qi
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    From the trace to the source of the theory, the pole-axis theory is based on the theory of the central place. However, the relationship between the two theories is not so easy. The point (such as cities), lines (the basic establishment of line formation such as traffic) and the surface (such as agricultural hinterland resources) form the three factors of the region. The regional developmental theory spreads according to these three theories and form the corresponding spatial structural model because of the different emphases. We can conclude that the core of the point forms the classic location theory that represent as the theory of central place; the core of the point and line forms the pole-axis theory and the pole-axis theory and the theory of central place form the two basic theories of the regional development. In the theory of central place, although we add up to the traffic factor so that construct the spatial structural model of k=4, the traffic factor is still ectogenic variable. Only in the pole-axis theory, do the point and the line become the endogenetic variable and they form the two indispensable factors of constructing spatial structure. It is not difficult to see that the organic combination of the point and the line forms the basic character of the pole-axis theory especially concentration to the line. Therefore, the theoretical innovation such as the regional accessibility and the spatial diffused mode forms the scientific basis of fording the pole-axis theory. The grand theoretical innovation endows the pole-axis theory with much practical values. The pole-axis theory is an important theoretical fruit in Chinese humane geography and the depth and the scope of its application are as perfect as the fruit of the agricultural regional layout. And then, we believe that we can build the spatial school of Chinese character through the research of spatial structure deeply.
  • ZHU Hong, XUE De-sheng, CAO Xiao-shu
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    This paper analyses the function of government officials in the progress of Hainan culture development in history, on the basis of concept of frontier culture and its forming, which points out that in the history,the officials always much more can give play to the development of the culture in frontier,because of their better culture background. In the history of Hainan Island,the officials made great contribution to Hainan's cultural development. Finally, the paper points out the officials were sent to the west of China from the developed areas (such as the coastal areas), and the officials were sent to the developed areas from the west of China may be considered as effective measures of developing frontier culture in new century.
  • YANG Yong-xing
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    This paper makes an introduction on chief activities of Quebec 2000-Millennium Wetland Event which was held in Quebec city, Canada in 2000. Main characteristics of the wetland development are showed from the Millennium Wetland Event. The wetland science has become an important discipline and research field of the scientific research in the 21st century, its research field is remarkably enlarged and its development is not balance in the world, the research level in developed countries is much higher than one in developing countries in wetland researches, but the difference between developed and developing countries is smaller and smaller in the research level. It also summarizes the hot points, forward position fields, main process and development trend of the 21st century international wetland science researches. The main hot points and forward position fields of wetland research in the world are as follows, conservation and management of wetland, development and succession of wetland, ecological process and dynamics of wetland, relationship between greenhouse gases and greenhouse effect and global environment change, theory and technique of creating wetland, restoration and reconstruction of degradation wetland, wetland ecosystem health, assessment and evaluation of wetland, wise utilization of wetland, peatland and peat. A vast amount of the academic works and papers on wetland were published with the rapid development of the wetland science in last few years. The theory system of wetland science is being perfected.
  • HUANG Tie-qing, ZHANG Yang-zhen
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    The essential aspects that should be considered in assessing the progress towards sustainable development are defined as development and sustainability. Eight classes of possible assessment result are inferred. The coordinate system of sustainable development assessment, composed of sustainability indicator as X-axis and development indicator as Y-axis, is proposed. The defects of matrix framework of sustainable development indicators are shown, and a new kind of framework called pyramid framework is proposed in order to overcome those defects. Several indexes are analyzed and compared, then the human development index (HDI) is chosen to reflect the development aspect, and the ecological remainder, which is the difference between ecological space and ecological footprint, is chosen to reflect the sustainability aspect.
  • SHEN Zhen-yao, YANG Zhi-feng, LIU Chang-ming
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    The reproducibility and its ability of natural water resource are introduced in this paper, the relationship between reproducible ability and refresh rate of water resource is discussed. The results show that it has many advantages to use refresh water resource per area per time as reproducible ability of water resource. The relation between reproducible ability and refresh rate of water resource shows that if the refresh rate of water resource is known, it is very easily to achieve the reproducible ability of water resource. The first order water resources areas in China and the second order water resources subareas of Yellow River are taken as an example to assess the natural reproducible ability.
  • GE Xiang-dong, ZHANG Xia, PENG Bu-zhuo, PU Li-jie
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    The poignant conflict between the rapid-growing population and the keeping-decreasing cultivated land has made the research on the dynamic monitoring system of cultivated land receive more and more attention. The early-warning system of cultivated land is the important portion of the dynamic monitoring system of cultivated land. Its purpose is to forecast the cultivated land system quantity and quality changes which exceed the critical value of space-time scope and dangerous degree, through analyzing the relevant factors of nature, society, economy and policy, which affect the farmland-developing situation. On the basis of ensuring the safety of food supplies, the early-warning system of cultivated land can alert the cultivated land situation to meet the need of society and economy development in the area during the period. At the same time it discusses the evolvement mechanism of cultivated land system, puts forward the amending scheme, monitors the system to avoid the grave depravation of the resource of cultivated land, supplies the service of the real-time data and model for the sustainable use manage of land and the actualization of the dynamic balance maintenance of total cultivated land. The strategic ultimate aim of the dynamic balance maintenance of total cultivated land is to ensure the safety of food supplies and to make the output capacity of deposit cultivated land and the output level per person increase. In fact, the urban expansion is the process during which the urban land system captures the cultivated land of the combination zone between urban and rural area. As the perceptive sensitivity of urban land system and the cultivated land system, the cultivated land price affects the captive force. The occupation cost of cultivated land is low; the social influence of cultivated land loss is not brought into the market cost. Both of these lead to low comparative benefit of cultivated land, which are the deep reasons of cultivated land loss. The social influence of cultivated land reflects the safeguard ability of corn security. From the dynamic balance of the total quantity of the cultivated land, the cultivated land alarming degree, which is judged by the cultivated land early-warning system, reflects the safeguard ability. During the cultivated land non-agricultural process, the critical alertness is taken for the cultivated land loss; the correct coefficient of the alarming degree is set up to modify the cultivated land price at the same time. The critical alertness of cultivated land and alarming modification of cultivated land non-agriculture cost should be founded on the classifying work of cultivated land. Based on the second general soil survey data, long-period soil monitoring data and relevant statistical data of cultivated land condition, integrated with the analysis of cultivated land investigation in typical area, an indicator system and warning model of cultivated land early-warning system of Xishan City are set up. According to this model, the analysis of the early-warning for the cultivated land of Xishan City is performed. The computation methods of the determinative coefficient of the cultivated land alarming degree and the correct coefficient of the cultivated land non-agricultural price are given in this paper.
  • JIN Ju-liang, WEI Yi-ming, DING Jing
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    Today water resource is very important in the world. The variation of annual runoff not only influences economy and people's living standards, but also restricts the economic development. To solve these problems, accurately predicting the variation of annual runoff is indispensable to scientifically utilize water resources. Being the output of a rainfall-runoff system of drainage basin, the annual runoff time series is a very complex dynamic phenomenon varying from region to region and changing with time, which includes lots of past information of all variations and hides many laws. The evolution treads of annual runoff time series are often time irreversible, nonlinear with weak dependence. Now traditional methods for predicting annual runoff usually use linear technique, but the forecasting precision is not satisfactory, owing to complexity of its intrinsic evolutions, and its close and complicated relationships to climate change and other hydrologic effect factors. In order to predict the high dimension complex dynamic systems of the annual runoff system, a new model-projection pursuit threshold regressive (PPTR) model is presented in this paper. A scheme of PPTR modeling is also given to reduce the computational amount, a new function of projection indexes is constructed, the relation of projection value and predicted object can be described with threshold regressive (TR) model, and it is suggested that both the function of projection indexes and the parameters of TR model can be optimized by using a real coded genetic algorithm developed by the authors. The examples of predicting annual runoff show that PPTR model is both practical and effective. PPTR model is simple and general, which overcomes the shortcomings of large amount of computation and difficulty of computer programming in traditional projection pursuit methods, benefits the more applications of projection pursuit, and gives a new approach to resolving the high dimension, nonlinear complex predictive problems.
  • SHEN Zheng-ping, MA Xiao-dong, ZENG Zun-gu
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    In regional tourist resources development and allocation, the structure of tourist resources often plays an important role. The length of the new Eurasian Continental Bridge in China is more than 4000 km, it is one of the main axes of Chinese economic allocation, the Outline of the Tenth Five-Year Plan for National Economic and Social Development requires that the economic belt relying on the new Eurasian Continental Bridge should be established. The section along the new Eurasian Continental Bridge in China, which is called the economic belt of the new Eurasian continental bridge in China in this paper, is not only rich in the tourist resources with a great quantity of landscape, various types and wide distribution, but also has the distinguishing feature. However, because of the low level of economic and social development in this area and the lack of scientific plan, the tourist resources are not fully utilized over a long period of time, and especially in the spatial structure, they are both uneven and irrational. Therefore, it is of great importance to make research into the structure, the development and the allocation of the tourist resources.Firstly, regarding 53 tourist landscape regions in this economic belt as the unit of research, combining qualitative method with quantitative method, this paper analyzes the structure types, spatial structure, threshold structure and developing hierarchical structure of the tourist resources in the economic belt, and finds the features in four aspects: 1) chief of the structure types is cultural tourist landscape; 2) there are two cultural regions in the spatial structure; 3) the scale of China is main body in the threshold structure; 4) there are three levels in the development structure.Secondly, with the above study, this paper puts forward the main aims, the overall thinking, the model of spatial allocation and the organization in time and space of tourist resources development in the economic belt, and places emphases on two of them: 1) it is the main aims to build up a tourist belt exerting a tremendous worldwide influence around 2010; 2) to sum up the spatial allocation model of tourist resources development with 1 core, 4 grown poles, 5 nodes, 1 main axis, 3 expanding axes, 18 characteristic routes and 5 divided functional regions.Thirdly, from the distinctive features and developing situation of the tourist resources in 5 tourist regions of the belt, this paper probes into the rational development of them respectively.Lastly, in view of the relative problems, the paper discusses the strategical measures of the tourist resources development in this belt in aspects such as government role and organization coordination, relationship between development and protection, image creation, etc.
  • FAN Zi-li, MU Gui-jin, MA Ying-jie, MA Ying-jun
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    Before the 1600's, the northern piedmont of the Tianshan Mountains was an area dominated by animal husbandry, the paleo-oases opened up by the "station troops" were spottily distributed along the traffic routes and were frequently abandoned. During the period from the 1700's to the mid-1900's, except the reclamation of the "station troops", the major efforts were devoted by the "local people" to open up the wasteland, which made the social development here to enter the period of semi-farming and semi-grazing. The old oases formed during this period were intermittently distributed in a small area. After 1949, the old, decentralized and small-sized oases have been connected by the new oases through the large-scale land reclamation and cultivation, and the oasis group and belt paralleling the Tianshan Mountains have formed. The oases in this region are mainly developed by the immigrants from other provinces, and they are developed very rapidly. Moreover, there is a continuity from the paleo-oases to the old and new oases, which is quite different from the situation of many paleo-oases in Tarim Basin because they have evoluted as the deserts, gobi deserts, and wind-erosion lands.
  • ZHAO Xin-yi, ZHANG Hui-yuan, WAN Jun
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    The climatic change in the past and future can impact the nature and humankind, e.g. the change of climate elements can cause the change of climate zones, which will effect the natural regions and the activities of humankind. Based on the analysis of the change of temperature during the 1950s to the 1990s in the Qinghai-Tibetan Plateau, the change of the index indicating climate zones is discussed in this paper. Then the possible change of climate zones under the scenario of cliamtic change in the future is pointed out.In the past 40 years, the change of the index indicating climate zones is as below; 1) The period during which the daily mean temperature is above 10℃, is becoming longer by the rate of 2.0-4.0 d/10a in some areas in the Plateau and is unchangeable in other areas. 2) In the warm and cold times, the difference of the periods during which the daily mean temperature is above 10℃, is 0-20d. The monthly temperature in the month whose temperature is highest in a year, is larger by 0.1-2.0℃ in the warm time tham that in the cold time.Following the scenario of the 2.0℃ rising of the annual temperature in the plateau, the boundaries and areas of current climate zones will change, but the character of them is unchangeable. The change of those zones is: 1) The eastern boundary of plateau frigid zone will move westward by 1.0 degree so that the frigid zone will be limited on the west of 90°E in the future. 2) The eastern boundary of plateau sub-frigid zone will move westward by 3.0 degree and reach the 100°E; the south-eastern boundary of the sub-frigid zone will shrink towards north-west by 100km or so; the part of the plateau sub-frigid zone in the northern plateau will be small and have the character of plateau temperature zone.3) The temperature zone in the future will expand in the plateau, especially in the eastern and northern parts; meanwhile the cumulated days with those days whose temperature ≥10℃ in the future will be more and the temperature of the warmest month will rise. 4) In the future the cumulated days with those days whose temperature ≥10℃ will be more in the sub-tropical and tropical zones, but the boundaries of them are still.
  • CHEN Qing-qiang, SUN Yan-min, SHEN Cheng-de, PENG Shao-lin, YI Wei-xi, JIANG Man-tao, LI Zhi-an
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    Two soil profiles were excavated at the forest vegetation zone and the shrub-meadow transitional zone of Dinghushan Mt. (23°09'-23°11'N,112°30'-112°33'E), and thin-layer sampling were conducted for studies on soil carbon dynamics of mountainous soils in the subtropical area. Based on 14C radioactivity of soil organic matters (SOM), SOM turnover rate (m) is calculated with a numerical model for the upper sections with SOM Δ14C value greater than zero, due to incorporation of 14C produced by atmospheric nuclear weapon testing (Bomb 14C) in the 1960s. As for the lower section with SOM Δ14C value less than zero, the effect of Bomb 14C may be neglected due to the slow turnover rate of SOM, and value m is calculated by one specific equation. Value m decreases downward, and is greater than 0.01a-1 at the upper 12cm section of the soil profiles, then, value m reduces abruptly downward, and is about one magnitude less than that of the above specimen. From 12cm on, value m reduces consistently with depth, till the minimum at the deepest of the profiles. This suggests that soil organic matters are composed of various compartments with different turnover times (T). Rapid compartments (T < 10a) are predominated at the upper 12cm section, slow compartments (100a<T < 1000a) turn to be the main part of SOM downwards, and stable compartments (T > 1000a) are predominated at the lower sections of the profiles. CO2 production resulted from SOM turnover is calculated based on value m, organic carbon content, soil bulk density and soil section thickness. The results suggest that the CO2 production from the upper 12cm section is about 98 percent of the total CO2 production of one profile. Therefore, the upper 12cm section is the main contributor for CO2 emission due to SOM decomposition in one soil profile. CO2 flux of the upper 12cm section of SL profile is 0.1233gC/cm2·a, which is about one magnitude higher than that of the upper 12cm section of GC profile. This is ascribed to that value m and organic carbon content of the upper 12cm section of SL profile are greater than those of the upper 12cm section of GC profile, respectively. For example, value m of the upper 12cm section of SL profile are greater than 0.1a-1, and those of the upper 12cm section of GC profile are from 0.01a-1 to 0.08a-1. Value m of the uppermost specimen is 0.402a-1 for SL profile, and is 0.078a-1 for GC profile; the former is about one magnitude higher than the latter. The aboveground vegetation types contrast obviously between SL profile and GC profile, which results in different primary production of aboveground vegetation for the two spots. Soil organic carbon content and value m of SOM are controlled directly by primary production of aboveground vegetation. Therefore, aboveground vegetation is the key factor controlling SOM turnover and the corresponding CO2 production of soil profiles within one climatic zone, which give scientific supports for increasing soil carbon sink through afforestation. The upper soil section has high SOM content and great value m, and is apt to be eroded away, thus, the upper section of one soil profile is prone to be CO2 source. Plant debris is the main source for SOM of the upper soil section. Therefore, to reduce plant debris production and to increase the biomass of deep roots, in order to transfer more organic matters into the deep, may be one effective measure for reducing and slowing down the emission of CO2 due to SOM turnover. For this purpose, vegetation with high underground biomass should be planted firstly under all possible conditions, which needs comprehensive cooperation between soil scientists and botanists.
  • WANG Sui-ji
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    Many fluvial rivers in southern China are anabranched river pattern and most of them have been studied. But the multiple channel fluvial system on the delta plain of the Ganjiang River differs from the anabranched river pattern. The multiple channel system formed spontaneously. It was not controlled by rocky or man-made nodes whereas the anabranched river was. The multiple channel system belongs to anastomosing fluvial pattern because it has the basic characteristics of anastomosing fluvial pattern in geomorphology and sedimentology such as the small channel width/depth ratio, low channel gradient, cohesive fine graind levees, interchannel wetlands and floodplains, etc. Although the Ganjiang River has low concentration of sediment, its flood plains or interchannel lands have similar sedimentary rate to that of the channels due to the import and aggradation of suspended sediment carrying by the frequent overbank flow during flood periods. The fine grain sediment of the levees that has high cohesive intensity maintains the channel stability.
  • LUAN Wei-xin, WANG Mao-jun
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    Based on the thorough analysis on the relationship between the level of urbanization and the area of infield, this paper makes a study of the relationship between the improvement of the level of urbanization and the variation of infield area in Dalian City and reaches some conclusions as follows: first, there is reverse correlation between the construction land per capita and the dimension of the dwelling; second, on the whole, the demand for the construction land in big or middle cities has been ensured but there are deficiencies in rural dwellings; third, based on the full apprehension of potential in the rural dwellings, with the development of urbanization, the general dimension of a variety of dwelling construction land will diminish, so improving the level of urbanization is an important solution to ease up the imbalance between supply and demand of infield. Confronted with the present situation, the author recommends that: with the general new plan of the utilization of land, we should give more attention to the arrangement of the construction land of rural dwellings; enhance the plan to the village and small town in countryside; rigorously enforce the regulation system of rural construction land; make more research on the relationship between the improvement of the level of urbanization and the change of infield.
  • HE Xing-dong, GAO Yu-bao, DUAN Zheng-hu, ZHAO Ai-guo, CHEN Heng
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    Determininga suitable irrigation manner is a key problem for establishing sand-fixation plantation system along Tarim Desert Highway. A series of comparison experiment about furrow irrigation, basin irrigation and drip irrigation, according to the merits and demerits themselves, the former research results and site conditions, were made on the plot L292 along the Highway. After comparing and analyzing the plant growth,the changes of salts content in the sand layer and the irrigation system as well as the cost input, it is concluded that drip irrigation is the best irrigation manner for constructing sand-binding plantation along Tarim Desert Highway because it is not influenced by dune landform, it ensures plant regular growth and its water utility efficiency is the highest as well as its cost is the lest.
  • WU Zheng-fang
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    As the basis of energy and substance, temperature and water play very important role in distribution of vegetation zones. Their long-term scale change and short-term scale fluctuation are essential causes of formation and distribution of vegetation transition zone. By using 90% ratio of eco-climatic factor's assurance of Thornthwaite PE as upper limit and 10% as lower limit of vegetation transition zone, forest vegetation transition zones of Northeast China are quantitatively classified. And 80% ratio of eco-climatic factor's assurance of Thornthwaite Im as upper limit and 20% as lower limit of vegetation transition zone forest/meadow/ prairie vegetation transition zones are classified.
  • SUN Dao-wei, YU Mu-qing, TIAN Wei, FENG Li-quan, DONG Zhi-xiang
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    Developing green food is one of the leading-industries in constructing eco-province in Jilin Province. A pre-evaluation of the agricultural environment in Jilin Province was made according to the standards for the green food production base just after the government made the green food development strategy. After the soil, water and air quality having been evaluated respectively, we draw a conclusion that there are great environmental superiorities in developing green food in Jilin Province. In order to guarantee the environmental quality of green food production base it should be founded a bit farther away from city, especially in the direction that most of the winds blow, also irrigation water should not be taken from where the city sewage just flows in. The whole Jilin Province was divided into four kinds of areas according to the natural conditions and the distribution of natural resources, which are the east mountain area, middle Songliao Plain, west Songneng plain and suburb area. Then the strategies of developing green food for each of the four areas were put forward in the paper.
  • BAI Jun-hong, DENG Wei, ZHU Yan-ming, ZHAI Jin-liang, ZHANG Yu-xia
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    This paper studied the vertical discribution characteristics of soil organic matter and total nitrogen in soil profiles, and their horizontal distribution characteristics in the surface soil of wetlands in Xianghai Nature Reserve and Horqin Nature Reserve, respectively. The results show that, in contrast to Horqin Nature Reserve, there exists higher spatial variation for soil organic matter and total nitrogen in Xianghai Nature Reserve, their variation coefficients can be more than 90%; moreover its surface soil holds more soil organic matter and nitrogen in Horqin wetland; its rate of carbon fixing is slower than that of nitrogen accumulation in Xianghai wetland; its degree of salinity is also more severe than, Horqin wetland and its wetland plants in Xianghai assimilate more salts than those in Horqin wetland; in addition, the distribution of soil organic matter and total nitrogen is influence by pH values more strongly.
  • LI Jun-ran, CHEN Li-ding, FU Bo-jie, ZHANG Shu-rong, LI Guang-qing
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    Water samples were taken from May 1999 to Oct.2000 and land use investigation was carried out in Aug. 2000 in Yuqiao Reservior watershed. Using the functions of space overlapping and graph computing of GIS, related data was collected to analyze temporal and spatial characteristics of non-point source N in surface water of the study area. The results indicate that the peak value of NH4+-N appears in the low-water period while the peak value of NO3--N displays in the high-water period; On spatial, peak value of NH4+-N appears in the central plain area followed by the southern rolling area and northern mountain area, but the diversification of the content of NO3--N in the surface water of the watersheds does not have regular rules. Topography, land use, land cover, human activities and the influencing factors of nitrifcation and denitrification were considered in each region (northern mountain area, central plain area and southern rolling area) of the study area to explain the variance of NH4+-N and NO3--N, and proposal about sustainable watershed development was brought forward as well.
  • FAN Jian-rong, LIU Shu-zhen, ZHONG Xiang-hao, LI Yong
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    Arid-hot valleys are special ecological type in southwest China. Land degradation/desertification is very severe in the arid-hot valley of the Jinshajiang River, the upstream of the Yangtze River, and threatens residents' living and sustainable development of national economy. The study on land desertification presently include type, distribute, cause of formation, harm, process and principle of forming. Land desertification degrees are still determined qualiatively. In order to take some countermeasures, rapid and accurate evaluation to the land desertification in this region should be done. The degrees of land degradation/desertification are determined by element analysis and multiplayer fuzzy evaluation in accordance with the complexity and fuzziness of land ecological system. The study shows those as following: Physiognomy, soil and vegetation is important factors for evaluation to land desertification in the arid-hot valley of the Jinshajiang River. According to the evaluation criteria system land desertification degrees are determined quantitatively with fuzzy evaluation. The evaluation result is accurate and reliable. It can tell us not only the degree of land degradation/desertification, but also its developing tendency and provide scientific basis and support of policy decision for the prevention of Land degradation/desertification and bringing it under control.
  • HU Guo-hua, Xia Jun, ZHAO Pei-lun
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    The river water environment system is a system with many uncertainties. The risk assessment quantifying the influence of uncertainties on river water quality have been paid attention to widely. However, the most of research on risk assessment for river water quality confined to quantify stochastic uncertainty of the river water environmental system using the method of statistics. The research on quantifying the risk due to grey uncertainty of the river water environmental system is done less. Based on the theory of probability and grey system approach, the concepts of grey probability, grey probability distribution, grey probability density, grey expectation and grey variance are defined in this paper. The concept of grey-stochastic risk for water quality concentrations exceeding the standard values is presented to quantify the influence of stochastic uncertainty and grey uncertainty on river water quality. The assessment models of grey-stochastic risk for water quality concentrations exceeding the standard values are established. In the assessment model for the individual parameter, the contaminant concentration is modeled as a random variable with a grey probability distribution and the risk for contaminant concentration exceeding the standard value is expressed with grey probability-the grey-stochastic risk for water quality concentrations exceeding the standard values. In the model of comprehensive assessment for multiple parameters, the river water environmental system is considered as the reliability system to undertake useful function, and the result that the concentration of anyone of water quality parameters exceeds the standard value shows that the useful function of river water environmental system cannot be guaranteed. Lastly, the comprehensive risks for water quality concentrations exceeding the standard values are computed by using the approach of reliability system. An example of application to evaluate the grey-stochastic risks for heavy metals concentrations exceeding the standard values in the Yellow River at the Huayuankou section is given. The results provide more information and are satisfactory.
  • QIU Guo-feng
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    Agricultural industrialization which is a new management way of agriculture production is one of the important ways to realize agricultural modernization in our country. Owing to various reasons in the undeveloped mountain areas such as the poverty of nature conditions and economic base, the weakness of the infrastructure and the lacking of the management methods of modernization, the following problems will appear. It is hard to establish the large scale and intensive leading enterprise during carrying out the agricultural modernization. The leading industrial products are poor. Comprehensive utilization rate of agricultural by-products is low. Extravalue is not so high, and so on. According to the practical exploration of agricultural industrialization in recent years in Meizhou, the article puts forward the strategies fully depending upon the advantages of natural resources to establish the leading industry, to choose the development model of industrialization in the light of local conditions, to utilize the law of market, to make the disposition of essential factors right, to explore the leader system and the functions of the government to meet the development of agricutural industrialization.