首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Based on the data from the Cost-benefit Data of Farm Produce and the China Agricultural Yearbook, this paper aims to examine the spatial and temporal change characteristics of total grain production and its affecting factors. The results show that: 1) During 1980 to 2007, total grain production increased from 3.20 × 108 t to 5.02 × 108 t in China, with annual increasing rate of 1.68%. From the regional disparities, most of the regions present increasing trend of total grain production except for several regions with higher level of economic development; 2) Grain sown area decreased from 1.17 × 108 ha in 1980 to 1.06 × 108 ha in 2007, which has negative effect on total grain production; 3) The increase of grain yield per unit area caused by land use intensity changes contributed to the increase of total grain yield greatly. However, as the land use intensity showed that farmers pay more attention to labor-saving input but not yield-increasing input, the less enthusiasm of farmers in grain production may become an important constraint on future grain production increase in China; 4) Based on the results, this paper proposed different land management policies in different regions, for example, the government should protect cultivated land, promote large scale production. As to the less developed regions, the government should pay more attention to agricultural subsidies to promote farmers’ enthusiasm in grain production.  相似文献   

2.
During the last 30 years,China has witnessed rapid economic growth and dramatic urbanization,with about 1.2 × 107rural people migrating annually into urban areas.Meanwhile,especially since 1995,the rural population has been declining,which is closely linked to land circulation and the increase in farm size in many villages.Increasing scale of farming operations is often regarded as a key to avoiding the abandonment of farmland and to increasing the income of rural farmers.However,until now,there has been little research on the spatial and temporal variability of farm size at the national level in China.Using data from the national agricultural census and rural household surveys,this study examines the characteristics of land use circulation and the consequent changes in the area of farmland per household.The results show that: 1) 12.2% of rural households were involved in land circulation at the national level.The highest amounts of land circulation have occurred in those provinces where the farmland per capita is more than 0.2 ha or less than 0.1 ha;2) over 80% of households operate less than 0.6 ha of farmland;3) the proportion of mid-sized farms(between 0.2 ha and 0.6 ha per household) has decreased while the smallest and the largest farms have increased.This bears some similarity with the phenomenon known as the ′disappearing middle′,referring to the changes in farm size.This study establishes a framework for interpreting the factors affecting the changes in farm size in China,which include two promoting factors(urbanization and agriculture) and four hindering factors(agricultual land system,household registration,stable clan system,and farmland loss).  相似文献   

3.
In recent years, great economic output of land has been achieved in economic-technological development areas in China, but the intensity of land use in some of these areas is very low. The degree of the low intensity of land use needs to be evaluated. The current method of comprehensive evaluation and grading by one index system has the limitations due to the existence of differences between regions and industries. This paper evaluates industrial land use intensity by Total Factor Productivity (TFP) analysis, which not only measures the intensity but also illustrates the ef-ficiency of input factors. This method is applied to the Beijing Economic-technological Development Area (BDA). A comparison analysis on factor use efficiency and input structure of capital and labor between industries is also carried out in the absence of a labor-income ratio.  相似文献   

4.
Integrated transportation and land use studies are of major interest to planners because they consider the interaction between transportation development and land use change. Quantifying the impact of transport infrastructure on land use change is necessary for evaluating the role of transportation development in the process of land use and land cover change in the urban-rural fringe. Taking Qixia District of Nanjing City, Jiangsu Province, China as a typical urban-rural fringe area, this paper analyzes the patterns and characteristics of land use change along three major transportation arteries using land use data from 2000 and 2008. We examine the spatial differentiation and gradient of land use pattern around railway, expressway, and highway corridors to investigate whether land use change in the urban-rural fringe is related to distance from transportation arteries and to clarify the varying impacts of different forms of transport infrastructure on land use patterns. We find that construction land generally tends to be located close to major transportation arteries, and that railways have the most obvious influence on land use change in the urban-rural fringe, while the impact of expressways was not significant. We conclude that there exists a causal relationship between the presence of transportation arteries and land use change in the urban-rural fringe, but this relationship varies across different types of linear transport infrastructure.  相似文献   

5.
基于青岛市区2005年4月和2015年4月的TM影像,利用ENVI中监督分类法,结合人工目视解译,得出2005年和2015年青岛市区土地利用类型分布情况。利用土地利用类型动态模型,分析了10年间青岛市土地利用类型的变化规律。认为2005—2015年,青岛市土地利用类型产生了较大的变化,建设用地、耕地、水面、草地、林地的面积变化显著。其中,建设用地面积增加200.98 km~2;耕地面积减少105.89 km~2;水面面积减少76.68 km~2;草地面积减少69.53 km~2;林地面积增加54.45 km~2;未利用土地面积减少。说明青岛市区处于土地利用发展的时期,政府应该注重土地资源的合理利用。  相似文献   

6.
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   

7.
本文以扬州市市辖区为例,利用2001年的ETM影像与2007年的ALOS影像两期遥感数据,采用面向对象的信息提取方法,获取了扬州市2001年与2007年两期土地利用空间分布图.在此基础上,研究了CLUE-S模型的原理及CLUE-S模型的应用;探讨了CLUE-S模型所需数据、驱动因子选取、模拟参数设置、模拟结果获取等,进...  相似文献   

8.
The influence of labor migration on rural household land transfer has been hotly debated in academic circles, which focuses on whether part-time employment leads to land transfer. Using survey data on rural households in the Sichuan Province, and applying the theoretical framework of new economics of labor migration, this study explores the influences of labor migration on the direction and scale of land transfer from the perspective of rural household structure. The results indicate that: 1) the quantity of laborers has significant influence on the direction and scale of land transfer. The larger the on-farm labor variable (Labor), the lesser the possibility that land will be rented-out and the amount of land rented out will also be smaller. In addition, there is a greater probability that land will be rented-in and the amount of land rented-in will be greater. 2) The greater the ratio of off-farm laborers to rural household laborers (Off-farm) the greater the possibility that land will be rented-out. In addition the higher the ratio of on-farm laborers to the total household laborers (On-farm), the larger the possibility that land will be rented-in. Meanwhile, if the household has individuals at the age of 64 or older (Old) who are engaged in agriculture, there is a smaller possibility that land will be rented-out. 3) the ratio of part-time laborers to rural household laborers (Pluriactivity) have significant inverse U-shaped influences on the rent-in of land as well as the amount of land rented-in. The inflection points are 33.27% and 14.10%, respectively. Such findings confirm the significance of this study in better understanding the influence of labor migration on rural household land transfer.  相似文献   

9.
家庭联产承包责任制实现了土地所有权和使用权的初步分离,使农民获得了相对独立的承包经营权,极大地调动了农民的生产积极性。然而,随着农村经济社会的发展,人地矛盾日益激化,土地的边际生产力已出现明显的递减趋势,土地小规模家庭经营,农业的比较利益大大下降;同时,农村的剩余劳动力涌向经济较发达的大中城市,城市化进程骤然加剧等,使得土地家庭承包经营这一土地制度逐渐显露出自身的缺陷。在稳定农村土地承包关系的前提下,促进农村土地流转,可以在一定程度上发挥土地的规模效益,促进农村经济社会的健康持续发展。  相似文献   

10.
Analyzing spatiotemporal dynamics of land use and land cover over time is widely recognized as important to better understand and provide solutions for social, economic, and environmental problems, especially in ecologically fragile region. In this paper, a case study was taken in Zhenlai County, which is a part of farming-pastoral ecotone of Northeast China. This study seeks to use multi-temporal satellite images and other data from various sources to analyze spatiotemporal changes from 1932 to 2005, and applied a quantitative methodology named intensity analysis in the time scale of decades at three levels: time interval, category, and transition. The findings of the case study are as follows: 1) the interval level of intensity analysis revealed that the annual rate of overall change was relatively fast in 1932–1954 and 1954–1976 time intervals. 2) The category level showed that arable land experienced less intensively gains and losses if the overall change was to have been distributed uniformly across the landscape while the gains and losses of forest land, grassland, water, settlement, wetland and other unused land were not consistent and stationary across the four time intervals. 3) The transition level illustrated that arable land expanded at the expense of grassland before 2000 while it gained intensively from wetland from 2000 to 2005. Settlement targets arable land and avoids grassland, water, wetland and other unused land. Besides, the loss of grassland was intensively targeted by arable land, forest land and wetland in the study period while the loss of wetland was targeted by water except for the time interval of 1976–2000. 4) During the early reclamation period, land use change of the study area was mainly affected by the policy, institutional and political factors, followed by the natural disasters.  相似文献   

11.
The relationship between livelihood diversification of farm households and cultivated land utilization has become a core research topic related to global environmental change. Agro-pastoral ecologically-vulnerable areas face challenges such as insufficient ecosystem conservation, low agricultural production, and weak economies. In this study, 215 farm households from Zhengxiangbai Banner, Taibus Banner, and Duolun County of Inner Mongolia were surveyed. The sustainable livelihoods framework of the United Kingdom(UK) Department for International Development(DFID) was used to measure the livelihood capital of these farm households. A one-way analysis of variance(ANOVA) was applied to examine the differences in the livelihood capital of different types households, and a correlation analysis was applied to analyze its impact on cultivated land utilization. Results showed that households with non-farming activities accounted for 64.7% of the total surveyed households, and non-farming employment was becoming more prevalent. Physical and financial capital was the driving factors for livelihood diversity. Each livelihood capital had key factors that affected household farmland use behaviors, such as the age of householder, the labor ratio, proportion of income, farmland scale, number of machines, and these had a significantly positive or negative influence on farmland use. Full-time farming households were more likely to transfer the land into cultivation and invest more labor, while non-farming households with high income were likely to transfer farmland out and invest more money to develop efficient farming or improve the employment skills. The results of this study suggest that policymakers need to fully consider livelihood changes of local households. It is effective to strengthen labor training, create farmland market and improve the efficiency of farmland utilization. We hope to achieve a win-win scenario to improve local economies and ecosystem conservation.  相似文献   

12.
亚像元制图作为一种降尺度分类方法,可利用低分辨率影像获取高分辨率分类图。本文旨在探讨亚像元制图的降尺度分类结果与高分辨率影像分类精度和分类特征上的一致性。实验以天津市津南区和北京市海淀区为研究区,分别对中空间分辨率影像(TM或HJ)进行亚像元制图和对高空间分辨率影像(ALOS或ZY)进行硬分类得到相同空间分辨率的分类结果,从绝对精度、相对精度、空间结构和空间格局上,对2幅分类结果进行分析和评价。实验结果显示:(1)分类精度上,TM和HJ影像的亚像元制图结果,以地面验证样本为参考的绝对总体精度分别为84%和82%,以高分辨率影像(ALOS和ZY影像)硬分类结果,为参考的相对总体精度分别为82%和77%;(2)分类特征上,中空间分辨率影像亚像元制图结果的空间相关性较强、斑块数量较少、聚集度较高,但与高分辨率影像分类结果的总体结构相似,各类别的面积比例基本一致。因此,亚像元制图结果在分类精度和分类特征上与高空间分辨率影像分类结果具有较强的一致性,在缺少高分辨率土地覆被制图时,可将亚像元制图获取的降尺度分类图作为替代数据。  相似文献   

13.
In this paper, the artificial neural network (ANN) model was used to evaluate the degree of intensive urban land use in Nanjing City, China. The construction and application of the ANN model took into account the comprehensive, spatial and complex nature of urban land use. Through a preliminary calculation of the degree of intensive land use of the sample area, representative sample area selection and using the back propagation neural network model to train, the intensive land use level of each evaluation unit is finally determined in the study area. Results show that the method can effectively correct the errors caused by the limitations of the model itself and the determination of the ideal value and weights when the multifactor comprehensive evaluation is used alone. The ANN model can make the evaluation results more objective and practical. The evaluation results show a tendency of decreasing land use intensity from the core urban area to the periphery and the industrial functional area has relatively low land use intensity compared with other functional areas. Based on the evaluation results, some suggestions are put forward, such as transforming the mode of urban spatial expansion, strengthening the integration and potential exploitation of the land in the urban built-up area, and strengthening the control of the construction intensity of protected areas.  相似文献   

14.
Land use change in rural China since the 1980s, induced by institution reforms, urbanization, industrialization and population increase, has received more attention. However, case studies on how institution reforms affect farmers’ livelihood strategies and drive land use change are scarce. By means of cropland plots investigations and interviews with farmers, this study examines livelihood strategy change and land use change in Danzam Village of Jinchuan County in the upper Dadu River watershed, eastern Tibetan Plateau, China. The results show that, during the collective system period, as surplus labor forces could not be transferred to the secondary and tertiary industries, they had to choose agricultural involution as their livelihood strategy, then the farmers had to produce more grains by land reclamation, increasing multiple cropping index, improving input of labor, fertilizer, pesticide and adopting advanced agricultural techniques. During the household responsibility system period, as labors being transferred to the secondary and tertiary industries, farmers chose livelihood diversification strategy. Therefore, labor input to grain planting was greatly reduced, which drove the transformation of grain to horticulture, vegetable or wasteland and decrease of multiple cropping index. This study provides a new insight into understanding linkages among institution reforms, livelihood strategy of smallholders and land use change in rural China. Foundation item: Under the auspices of National Natural Science Foundation of China (No. 40601006, 40471009), National Basic Research Program of China (No. 2005CB422006)  相似文献   

15.
海口市海岸带土地利用时空格局变化分析   总被引:3,自引:0,他引:3  
在深入分析土地利用转移矩阵基础上,对单项土地利用类型动态度进行改进,引入信息熵和缓冲区梯度带法,提出了自然生态影响度的土地利用变化程度的概念、含义,并构建计算模型。对海口市南渡江东岸海岸带进行研究,得到以下结论:1991-2010年间建设用地增长最为明显,耕地面积减少量最大;信息熵持续增加,表明均衡度增加,快速城市化过程中各经济产业所需的职能土地类型已逐渐产生,区域发展逐渐走向成熟;土地利用变化程度指数能有效衡量土地利用类型变化的剧烈程度,而且能够测算这种变化对自然生态环境的影响大小,1991-2010年间偏离自然生态方向、较强变化以上的区域占总面积的20.60%,与耕地、林地转变为建设用地,以及林地转变为园地区域重合;趋向自然生态方向、较强变化以上的区域仅占总面积的2.42%;东岸海岸带受城市梯度辐射和开发区、大学城飞地影响,同时也受农业比较利益和土地利用调控政策影响。东寨港红树林面积略微减小,受城市化影响较小。研究表明:分层次、多种算法相结合的研究方法,可有效分析综合型海岸带土地利用时空格局变化特征及其驱动机制。  相似文献   

16.
Residential expansion is gaining more and more attention from government authorities and urban planners.However,most of the current urban models focus heavily on presenting economic,political and ecological objectives of urban development,while seldom taking the effects of human behavior into consideration.Multi-agent systems for land use/cover change(MAS/LUCC),which mainly concern the behavioral effects of stakeholders on the processes of land use/cover change,are promising to fill the gap.This article,based on the concepts of MAS/LUCC model,con-structs a multi-agent system for residential expansion model(MAS/RE)through the analysis of the behavior of gov-ernment authorities and households.The model takes complex human actions into account,namely urban master plan-ning,planning review and approval,policies of traffic,economy and environment,location and allocation choices of the households and their interrelationships.Taking Hongshan District of Wuhan City,Hubei Province as an illustration,the model is implemented on Arc/info platform to simulate residential expansion between 1996 and 2002.The study result shows that the model is suitable for understanding the process of residential expansion with the effects of human actions,and is especially effective for its capacity in presenting spatio-temporal and behavioral complexity.Therefore,the model can be a reference for policy-making for government authorities and urban planners.  相似文献   

17.
Since land and labor force are primary resources to be used and controlled by rural households, the allocation of labor forces will influence land uses, and further lead to land use conversion. The present study used the Binary Logit model to investigate the influence of labor force transfer, characteristics of rural households, location, and land market on agricultural land use conversion at rural household level. This study was conducted based on 329 valid questionnaires, which were obtained in Changshu, Rudong, and Tongshan counties, respectively representing the southern, middle and northern areas of Jiangsu Province. The results showed that land market participation, location, zonal difference and labor transfer had strong influences on agricultural land use conversion. The participation of land market had a strong positive effect on land use conversion, especially for the farmland converted to the fishpond. The nearer to the county seat, the more conversion of land use occurred. Particularly, the labor force transfer caused by wage employment decreased this conversion probability, while the labor transfer caused by self-employment led to more conversion; and the increasing of income from labor transfer increased the conversion. Moreover, land use conversions demonstrated zonal difference, which were more in Rudong and Changshu counties than in Tongshan County, and the factors influencing this conversion were different in the three regions.  相似文献   

18.
Influenced by artificial factors, landscape pattern of Yantai City, Shandong Province changes continu-ously. Revealing its landscape pattern and its changing process has a practical significance for the urban development and layout. Zhifu District, Development Zone, Laishan District and Fushan District in Yantai City were selected to study the landscape pattern. Remote sensing technology was used to obtain landscape information of different peri-ods. Under the support of Geographic Information System (GIS), the spatial landscape pattern of Yantai City was an-alyzed and simulated by using various special quantitative analysis models. The analysis shows that built-up area lies in the center of Yantai City, the outside is vegetable land. irrigated land, dry land, garden land and woodland.  相似文献   

19.
厦门城市空间拓展的生态敏感性评价   总被引:1,自引:0,他引:1  
在综合分析海湾型城市自然生态与社会生态属性的基础上,选取了高程、坡度、河流水库、植被覆盖、土地覆盖和生态保护区等6个因子,作为生态敏感性评价的指标。另外,借助GIS空间分析单因子评价与多因子加权综合评价方法,研究了生态敏感性程度及其空间分布特征,将厦门的生态敏感性划分为4级:不敏感、较敏感、中敏感和高敏感。综合评价结果表明,厦门市生态敏感性在空间分布上差异显著:高度敏感区占研究区总面积的28.1%,低敏感区和不敏感区分别占研究区总面积的27.9%和33.6%。中度敏感区占的比例较小,仅为10.4%。  相似文献   

20.
以1986、1996和2006年三期Landsat TM影像为基本数据源,采用最大似然法分类,并以同期高分辨率的SPOT5影像进行分类后处理,最后分类后变化检测法监测了福州市1986~2006年的土地利用变化及其转移模式。结果表明,福州市近20年间土地利用发生了较大的变化,城乡建筑用地处于快速增长阶段,而耕地数量却在不断下降。经济发展、人口增长、政府决策等因素是福州市土地利用发生变化的主要驱动力。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号