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1.
1IN T R O D U C T IO NAs we allknow,China isa countrywith vastpopulationand scarcelandpercapita(Y ANG and LI,2000)."T rea-suringlandverymuch,utilizinlgandrationallaynd pro-tectingthe cultivatedland conscientiously"is funda-mental statepolicyofChina.At the…  相似文献   

2.
1 Introduction The gradation of cultivated land is to assess the suitability of cultivated land for agricultural production in terms of natural and economic prop-erties of land (Feng et al. 2004). It can be used to evaluate sustainability of land use and …  相似文献   

3.
The conflicts among food security, economic development and ecological protection are the “sticking point” of undeveloped southwestern mountainous areas of China. The objectives of this study are to identify appropriate inte- grated indicators influencing the classification and gradation of cultivated land quality in the southwestern mountainous area of China based on semi-structure interview, and to promote the monitoring of cultivated land quality in this region. Taking Bishan County of Chongqing as a study case, the integrated indicators involve the productivity, protection, ac- ceptability, and stability of cultivated land. The integrated indicators accord with the characteristics of land resources and human preference in southwestern mountainous area of China. In different agricultural zones, we emphasize different indicators, such as emphasizing productivity, stabilization and acceptability in low hilly and plain agricultural integrative zone (LHP-AIZ), protection, productivity and stability in low mountain and hill agro-forestry ecological zone (LMH-AEZ), and acceptability in plain outskirts integrative agricultural zone (PO-IAZ), respectively. The pronounced difference of classification and gradation of cultivated land, regardless of inter-region or intra-region, is observed, with the reducible rank from PO-IAZ, LHP-AIZ to LMH-AEZ. Research results accord with the characteristics of assets management and intensive utilization of cultivated land resources in the southwestern mountainous area of China. Semi-structure interview adequately presents the principal agent of farmers in agricultural land use and rural land market. This method is very effective and feasible to obtain data of the quality of cultivated land in the southwestern mountainous area of China.  相似文献   

4.
1INTRODUCTION With the acceleration of the urbanization and industrial- ization of China, it is inevitable that cultivated land con- vertsto built-up land for industrial, commercial and resi- dential uses. During 1986- 2002 around 168.4×103ha cultivated land had converted to non-agriculture use an- nually (QU et al., 2005). Though the urbanization rate had increased from 17% in the late 1970s to 41% in 2004, China has a long way to go compared with the de- veloped countries whose urbani…  相似文献   

5.
The northeastern China is an important commodity grain region in China,as well as a notable corn belt and major soybean producing area.It thus plays a significant role in the national food security system.However,large-scale land reclamation and non-optimum farming practices give rise to soil degradation in the region.This study analyzed the food security issues coupled with global climate change in the northeastern China during 1980–2000,which is the period of modern agriculture.The results of statistical data show that the arable land area shrank markedly in 1992,and then increased slowly,while food production generally continually increased.The stable grain yield was due to the increase of applied fertilizer and irrigated areas.Soil degradation in the northeastern China includes severe soil erosion,reduced soil nutrients,a thinner black soil layer,and deterioration of soil physical properties.The sustainable development of the northeastern China is influenced by natural-artificial binary disturbance factors which consist of meteorological conditions,climate changes,and terrain factors as well as soil physical and chemical properties.Interactions between the increasing temperature and decreasing precipitation in the region led to reduced accumulation of soil organic matter,which results in poor soil fertility.Human-induced factors,such as large-scale land reclamation and non-optimum farming practices,unsuitable cultivation systems,dredging,road building,illegal land occupation,and extensive use of fertilizers and pesticides,have led to increasingly severe soil erosion and destruction.Solutions to several problems of soil degradation in this region requiring urgent settlement are proposed.A need for clear and systematic recognition and recording of land use changes,land degradation,food production and climate change conditions is suggested,which would provide a reference for food security studies in the northeastern China.  相似文献   

6.
1 INTRODUCTIONGuangdongProvincehasbeenwidelyknownasoneofthemostimportantindustrialbasesforexportinChina.IthasplayedanimportantroleineconomicreformanddevelopmentinChina.Inrecentyears,ithasattainedasustainableeconomicgrowthandkeptthefirstpositioninecon…  相似文献   

7.
As the important reserve land resources for food production,saline-alkali land should play a significant role to ensure the national food security in the context of global food crisis. The western Songnen Plain is one of main distribution regions of saline-alkali land in China,with great potential in agricultural development. In this study,the extent,transformation,spatial distribution and temporal change of saline-alkali land in the western Songnen Plain during 1954–2005 were investigated by using remote sensing and GIS spatial analysis methods. Saline-alkali land change was detected from a temporal series of topographic maps in 1954,satellite images of Landsat MSS in 1976,Landsat TM/ETM in 1988,2000 and 2005 through artificial visual interpretation. The results indicated a significant expansion in saline-alkali land area and aggravation in salinization. The area of saline-alkali land had increased from 401.48×103 ha in 1954 to 1 097.45×103 ha in 2005. While the ratio of light,moderate and serious salinized land areas changed from 6.72︰2.92︰1.00 to 1.25︰1.06︰1.00 in the study period. Grassland,cropland,swampland and water body were the major land use and land cover types from which saline-alkali land transformed. And the secondary salinization occured mainly in Da′an City,Tongyu County,Changling County,Daqing City,Dorbod Mongolian Autonomous County and Zhaoyuan County. Finally,seven large ecoregions and 14 corresponding sub-ecoregions were delineated out based on spatio-temopral dynamic characteristics of saline-alkali land and geo-relational environmental attributes. According to the results,measures of amelioration and ways of development of saline-alkali land in the western Songnen Plain were put forward.  相似文献   

8.
The land use patterns in Guyuan City, Ningxia Hui Autonomous Region of China, have changed greatly over the years, due to population growth and farming and stock raising development. This study, using 50-year statistical data of cultivated land and 14-year spatial data of land use pattern, analyzed the developmental stages, the character, and the spatial variance of farmland in the city, and discussed the driving forces of cultivated land changes based on empirical and conceptual statistical models. First, the change of cultivated land area went through different stages of rapid increase, fluctuating change, decrease and rapid decrease from 1949 to 2004, additionally, social and economic policies in different stages had an important impact on farmland variance. Second, from 1986 to 2000, the quantity of cultivated land increased, but its quality decreased. Third, social and economic factors are determinant factors in cultivated land transition. Five constructed paths explain cultivated land transition. Factors that have direct or indirect effects on farmland include the economy (Xeco), the population (Xpop), agricultural output (Xagr), and scientific input (Xsci). The sequence of impact was Xeco〉Xpop〉Xsci〉Xagr. Among all these impacts, Xeco was the major positive one, and Xpop was the major negative one. It is urgent to take measures or adopt a policy to stop the vicious cycle in eco-environment and agriculture production. Otherwise, negative patterns of farmland use will increase, and high-quality cultivated land will continue to decline.  相似文献   

9.
Deqing County of Guangdong Province is located in the tropic and subtropic mountain areas of China. Its area of cultivated land from landuse survey is 40% larger than the statistical data. Of all cultivated land, owing to flood, waterlogging, drought and barren soil, the high yield land occupies only 30% and the mid-low yield land 70%, which is far more than the percent by statistics. Because the statistic area of cultivated land is less than the actual, the per unit area yield by statistics is higher than the actual. These situations generally exist in the tropic and subtropic mountain area of South China. So the measures to protect the high yield cultivated land strictly, to improve parts of the mid-low yield selectively, to adjust agricultural structure further, and to control soil erosion, are necessary to make best use of its advantages and bypass the disadvantages.  相似文献   

10.
Food safety and its related influencing factors in China are the hot research topics currently, and cultivated land conversion is one of the significant factors influencing food safety in China. Taking the North China Plain as the study area, this paper examines the changes of cultivated land area using satellite images, estimates land productivity from 1985 to 2005 using the model of Estimation System for Land Productivity (ESLP), and analyzes the impact of cultivated land conversion on the land production. Compared with the grain yield data from statistical yearbooks, the results indicate that ESLP model is an effective tool for estimating land productivity. Land productivity in the North China Plain showed a slight decreasing trend from 1985 to 2005, spatially, increased from the north to the south gradually, and the net changes varied in different areas. Cultivated land area recorded a marginal decrease of 8.0 × 105 ha, mainly converted to other land uses. Cultivated land conversion had more significant negative impacts on land production than land productivity did. Land production decreased by about 6.48 × 106 t caused by cultivated land conversion between 1985 and 2005, accounting for 91.9% of the total land production reduction. Although the land productivity increased in Anhui and Jiangsu provinces, it can not offset the overall adverse effects caused by cultivated land conversion. Therefore, there are significant meanings to control the cultivated land conversion and improve the land productivity for ensuring the land production in the North China Plain.  相似文献   

11.
2005-2008年中国耕地变化对区域生产潜力的影响   总被引:3,自引:0,他引:3  
我国人多地少,粮食安全问题一直是国家关注的头等大事。而耕地资源与粮食生产能力是保障粮食安全的基础,因此,研究中国耕地变化对区域生产潜力产量的影响具有重大的现实意义,可以为国家相关决策提供科学依据。本研究基于2005-2008年最新的气象观测数据和卫星反演数据,并结合2005、2008年耕地数据及其变化数据,从耕地资源的数量变化与质量特征两方面,研究2005-2008年耕地变化对我国全境内光温生产潜力的影响。研究结果显示:在耕地的变化过程中,光温生产潜力增加区与减少区产量变化不对等:增加区增加785.14万t,减少区减少2543.61万t,净减少1758.47万t;增加区与减少区光温生产潜力单产不对等:增加区平均光温生产潜力单产为11.89t/hm2,减少区平均光温生产潜力单产为20.99t/hm2,后者约为前者的2倍;增加区与减少区空间分布不同:增加区主要分布在新疆、黑龙江、内蒙古、宁夏、青海等西北、东北地区,生态用地开垦是其增加的主要原因,占77.25%,减少区主要分布在江苏、安徽、山东、广东等黄淮海平原、长江三角洲、珠江三角洲地区,建设用地占用耕地是其减少的主要原因,占69.20%。  相似文献   

12.
Establishment of rural housing land standard in China   总被引:4,自引:3,他引:1  
On the basis of rural household survey in 12 provinces of China in 2005,this research built an econometrical model to find the area standard for rural housing land.This standard is expected to facilitate rural housing land administration,efficient and intensive housing land use and policy making.This research concludes:1) according to the household survey data,the average area for rural housing land in China is about 235.26 m 2,and the rural housing land mainly includes unused land(42.89%) and house construction land(37.76%) with the average floor-area ratio of 0.42;2) the indexes in the standard concern the factors such as location,landform,house form,household population and cultivated land area per farmer,which all have significant effects on rural housing land use;3) the reasonable area for rural housing land may be 150 m 2 in average before 2020,and the referential standards in different provinces are 120 m 2,130 m 2,140m 2,150 m 2,160 m 2,170 m 2,190 m 2,200 m 2,210 m 2,220 m 2,230 m 2 and 250 m 2 respectively;and 4) if there are less than two persons or more than five persons in a family,these standards need to be decreased or increased by 7%.When the cultivated land area per farmer is lower than the provincial average,the standards have to reduce by 3.5%.  相似文献   

13.
Spatiotemporal evolution of urban land uses in modern urbanization of China   总被引:1,自引:0,他引:1  
Taking social statistic data as basic data,this paper extended the meaning of urban land uses,highlighted the meaning of urban land uses in modern urbanization,which includes direct,indirect and induced land uses,quantitatively simulated the indirect and induced land uses by the substitution method of agricultural consumption and urban carbon emission and then,analyzed the spatiotemporal evolution of urban land uses in China during 1952–2005 by spatial analysis tool of Geographic Information System. The results indicate that the area of urban land use in China had been increasing since 1952,showing an inversed pyramid structure,i.e.,the directthe indirectthe induced. Specifically,Chinese urban land use has changed from concentrated distribution in Northwest China to balanced spatial distribution,and the eastern coastal area is under great pressure. Moreover,the northeastern region has moved into the induced dominant stage,while the western region remains at the indirect dominant stage. Finally,it is proposed that in order to guarantee the future demand of urban land use in China,ensuring the induced land use in the eastern region should be taken as a priority goal of Chinese developing policy.  相似文献   

14.
In China, the land resource per person is poor withregard to the huge number of population. According tothe recent data from the National Land Bureau, theaverage land per person is 0. 11 ha, much less than0. 25 ha, the average land per person in the world(FAN, 1997). On the other hand, a large scale ofrural land is to be transmitted into urban land upon thefast proceeding of urbanization. At present, the urbanpopulation occupies about 30% of the total in China. Ifthe percent become 50% (th…  相似文献   

15.
With a subtropical climate, Guangxi Zhuang Autonomous Region has a typical karst landscape. Rocky desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natural settings and human activities, because of which its eco- environment has been deteriorated in recent years, and farmland has been disappearing sharply at the same time. This, in turn, has exacerbated the poverty level in the rural areas of the region. In this study, we monitored the spatial distribution of rocky land desertification and its temporal evolution using Landsat TM/ETM images of 1985, 1995, 2000 and 2005. We also analyzed the driving forces of the desertification and its expansion. Through constructing regression models by using all the relevant variables and considering the lagged effects as well as fixed effects, we quantified the exact role of different factors causing rocky land desertification in the study area with some new findings. The new findings in this study are greatly helpful for preserving, restoring and reconstructing the degraded mountain environment in Guangxi and other karst areas in Southwest China, and also for alleviating poverty in the rural areas in the future.  相似文献   

16.
THE BENCHMARK LAND PRICE SYSTEM AND URBANLAND USE EFFICIENCY IN CHINA   总被引:3,自引:0,他引:3  
IINTRODUCTION oppeople’s commune,peasants were asked tojolnpro-ductlon cooperation bydonatingthelrla侣e possessedBefore 1949,private land ownership existed and assets such asland and la吧e production materialsthatland transactions were quite active.A household’s had been distributed Inlandreform.The members ofawealth Is directly correlated with the amount of land It production cooperation collectlvelyown all its propeftlespossesses.Af…  相似文献   

17.
The spatialization of population of counties in China is significant.Fistly,we can gain the estimated val-ues of population density adaptive to different kinds of regions.Secondly,we can integrate effectively population data with other data including natural resources,environment,society and economy,build 1km GRIDs of natural resources re-serves per person,population density and other economic and environmental data,which are necessary to the national manage-ment and macro adjustment and control of natural resources and dynamic monitoring of population.In order to establish population information system serving national decision-making,three steps ought to be followed:1)establishing complete geographical spatial data foundation infrastructure including the establishment of electric map of residence with high resolu-tion using topographical map with large scale and high resolution satellite remote sensing data,the determination of at-tribute information of housing and office buildings,and creating complete set of attribute database and rapid data update-ing;2) establishing complete census systems including improving the transformation efficiency from census data to digital database and strengthening the link of census database and geographical spatial database,meanwhile,the government should attach great importance to the establishment and integration o population migration database;3)considering there is no GIS software specially seving the analysis and management of population data,a practical approach is to add spe-cial modules to present software system,which works as a bring actualizing the digitization and spatialization of popula-tion geography research.  相似文献   

18.
Analysis on poverty in mountain areas based on off-farm industries   总被引:3,自引:0,他引:3  
This paper reveals that agricultural growth trend in China is strongly correlated with the growth of off-farm industries-the curve of net income from off-farm industries reflects the general characteristics of net income of households. That means the increase of net income of farm households is chiefly from off-farm industries,more than from agriculture. The authors therefore conclude that the “poverty“ in mountain areas or the gap between mountain areas and plain areas lies in the underdevelopment of off-farm industries in mountain areas. Finally, the authors make suggestions of strategic adjustment of economic structure: 1) present situation of mountain areas in China should be fully considered; 2) a full industrial system is not our desire; 3) advantageous industries should be promoted to create famous products; 4) industrialization and urbanization in mountain areas should be promoted and so on.  相似文献   

19.
济南市农村居民点用地潜力分析   总被引:3,自引:0,他引:3  
徐红 《山东国土资源》2006,22(10):58-61
城市化水平的提高,城市规模的扩大,农村居民点用地与耕地及城市建设用地的矛盾日益突出。通过对济南市农村居民点用地现状分析,指出土地利用程度低以及土地资源浪费是农村居民点用地普遍存在的现象。同时结合国家农村建设用地标准以及济南市地形特点,计算出济南市农村居民点用地的潜力巨大,占目前用地现状的33%,平原地区是用地挖潜的重点。在当前建设节约型社会的形势下,应从提高土地利用程度、节约用地等方面,尽快有效利用农村居民点用地。  相似文献   

20.
Introduction The shifting cultivation system is one of the most important agricultural systems in Luang Prabang and Oudomxay provinces, where many production systems are found in the uplands. The factors, determining the systems, include ethnicity,Journal…  相似文献   

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