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 23 毫秒
1.
黑河流域地处西北干旱区,水资源短缺是限制其中游绿洲农业发展、下游生态环境保护的首要原因。该流域的中游绿洲农业用水约占总用水量的80%,因此农业节水对流域发展至关重要。在干旱区绿洲农业节水探索中,众多学者主张通过节水技术来提高用水效率,而关于农业种植结构调整对农业节水影响的定量研究较少。本文采用2012年黑河流域蒸散发数据、土地利用数据、降水数据和农业经济统计数据,定量分析黑河中游主要作物需水特征和用水效率差异,尝试从调整作物种植结构角度为其绿洲农业节水提供依据。结果表明:(1)研究区4种主要作物中,玉米生长期需水量最大,其次为小麦、油菜和大麦;(2)考虑降水补给,发现大麦和油菜生长需水可很大程度上依赖降水,而小麦和玉米则需要灌溉,且玉米灌溉需水量远超小麦;(3)作物用水效率由高到低依次为大麦、油菜、小麦和玉米。从用水效率角度而言,考虑种植区位,在黑河中游适当扩大小麦种植规模更有利于提高中游农业用水效率。  相似文献   

2.
Based on dynamic theory of system, agriculture is a complex system composed by element, structure, function and development. Firstly, this paper analyzes their connotation and relationship, which could be simply described that in virtue of element integrating and structure optimizing, agricultural system may achieve multifunctionality to meet increasingly diverse demands. As a case study of Suzhou, it concludes that Suzhou has a LP-dependence on agricultural element, and the growth extent of agricultural productivity correlates to the ratio of agricultural labor reducing rate to farmland reducing rate. Agricultural structure of Suzhou changed with time, and in the early 1980s and 2000s it was most notable. Correspondingly, agricultural function has experienced a succession process: ‘production’, ‘production-living’, and ‘production-living-ecology’. At last, based on questionnaires and interviews, some new characteristics and problems of agricultural development in coastal developed region of China have been put forward. Meanwhile, some typical patterns of modern agriculture in Suzhou which adapt to system evolving are also brought up such as export-oriented agriculture, enterprises-leading agriculture, agricultural science and technology parks, characteristic and stereoscopic agriculture, tourism and sightseeing agriculture. Foundation item: Under the auspices of National Natural Science Foundation of China (No. 40635029, No. 40771014)  相似文献   

3.
PRESSURE OF WATER SHORTAGE ON AGRICULTURE IN ARID REGION OF CHINA   总被引:2,自引:0,他引:2  
1INTRODUCTIONWiththedevelopmentoftheworld,waterdemandisincreasing,especiallywiththegrowthofpopulationinthelast50years,waterdemandforirrigationhasgreatlyincreasedforfoodproduction.Inthearidandsemi-aridareas,watershortagebecomesaheavierproblemtorestrictfoodproduction,localeconomyandenvironmentalprotection.China,with22%ofthetotalpopulationintheworld,hasonly8%offreshwaterintheglobe;watershortagehasaffectedagricultureandresident'slifeinthenorthernChina.SomescientistsindicatedthatChina'swaters…  相似文献   

4.
This paper examines spatio-temporal characteristics of an oasis economy and its relationship with water and mineral resources in the Turim River Basin from 1965 to 2005. A spatial autocorrelation model, the center of gravity model, and index system of the regional central city are used to probe the evolution laws of spatial structure of oasis economy. The study finds that: 1) The economic centre of gravity, whose variation track during this period follows linear rote law, was moving from headstream to middle reaches of the Tarim River. 2) Positive spatial autocorrelation which showed a waving and ascending trend of regional economy was significant and the neighbor effect of regional economic growth was strengthened continuously. 3) The regional economic centre was located in Hotan City before 1980, moved to Aksu City during the 1980s and to Korla City after 1990. We conclude that above all, during the recent four decades the evolution of the oasis economy in this region has gone through three stages: a traditional agriculture stage (before 1980), oasis agriculture and agricultural product processing stage (1980-1990) and oasis energy industry stage (after 1990). Furthermore, the dependence degree of the oasis economy on natural resources in different stages are studied by using dominance index, regression model, and grey relation method, which shows that an oasis economy highly depends on water resources in the oasis agriculture and agricultural product processing stage while it depends more on mineral resources such as oil and natural gas during the oasis energy industry stage.  相似文献   

5.
农业对外开放是农业现代化的重要推动力量,农业“走出去”又是农业对外开放的有机组成部分,中国农业如何“走出去”已成为当前中国农业面临的一个重要课题.农业跨国种植是农业“走出去”的一种重要模式.在对国内外农业跨国种植历程和特点分析的基础上,从政府、企业、经济效益、政治因素等角度对中国农业跨国种植兴起的原因、障碍因素进行了剖析,总结了国内外农业跨国种植的经验及启示:重视土地使用权的获取,农业跨国种植应立足于带动国内要素输出,种植品种的选择可因“走出去”主体不同而有所侧重  相似文献   

6.
This paper introduces the experiences and models of land resources use in China. They are: (1) to protect farmland is as the basic state policy; (2) to carry out land resources survey and land use planning; (3) establishing a resource-saving agricultural production system with land saving as its priority; (4) to develop agriculture in the whole territory and explore food resources; (5) improving eco-environment and protecting land resources; (6) population control'and moderate consumption to release the pressure on land resources; (7) the integrated development and experiment of the typical regions.  相似文献   

7.
Under the special background of China, the cooperative innovation between different government-industry-university-research institutes plays an increasingly important role in the agricultural field. However, the existing literature has paid little attention to it. Considering the cooperation patents, published in the agriculture field stemming from the Full-text Database of China Patents as the study object, the spatial and institutional attribute of the authors as the data source, and by combining the social network and spatial econometrics analysis, this paper analyzes the structure evolution characteristics of cooperative innovation networks of agricultural government-industry-university-research institute in the city level of China in 1985–2014, based on the triple helix theory, with the influence factors discussed. This shows that, 1) since 1985, China's agricultural innovation level has been substantially increased, but the development degree of the cooperative innovation network is low, and the patent cooperation mainly relies on authors in the same unit; 2) enterprises play a leading role in the agricultural cooperative innovation. The effect of the government and hybrid organizations driven by the government is not obvious; 3) the cooperative innovation in the province and city dominates, and a multi-pole pattern has been formed. The cooperative innovation network structure evolves from a single helix empty core and double helix multi core to a double helix hierarchical network; 4) the city's science, education funding and personnel investment are key factors determining the agricultural cooperative innovation, while the agricultural development of the city presents slight negative impacts on it. The spatial mismatch of supply and demand is present in the technical cooperative innovation of China's agriculture. Therefore, the science enhancement and education investment to big agricultural provinces should be promptly implemented.  相似文献   

8.
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   

9.
精准水稻种植信息系统结构、管理与应用   总被引:2,自引:0,他引:2  
精准农业是当今世界农业发展的新潮流 ,中国 2 1世纪农业的发展方向之一。稻谷产量占我国粮食总产量的 4 0 %左右 ,实现精准水稻种植具有重大意义。在上海市农工商现代化农业园区“精准农业试验与示范基地”开展的水稻精准种植试验 ,结果与其他地块相比较 ,化肥使用量减少 1 5 % ,单产提高 8% ,总收益提高 1 8%。精准水稻种植信息系统是实现水稻精准种植的核心 ,目前完成 PRC/ INFO1 .0版本的开发 ,本文介绍了系统的结构、功能和技术特点。  相似文献   

10.
《山地科学学报》2020,17(1):147-155
Agricultural development in povertystricken areas is a major problem affecting agricultural modernization in China. This study discusses the restrictive factors affecting agricultural development in impoverished areas in China. A typical impoverished mountainous area, Min County,was selected for a case study. A regression analysis on the factors and characteristics of agricultural development in Min County between 1982 and 2017 was performed in this study. Taking agricultural output as the dependent variable, we selected nine main inputs of agricultural production in impoverished mountainous areas as the independent variables. Ridge regression analysis was carried out by testing for unit root and co-integration to verify the equilibrium relationship of the data. The results showed that the real Gross domestic product(GDP)per capita, the non-grain area ratio, the proportion of government expenditure on agriculture support to total expenditure, and the amount of chemical fertilizer applied in unit cultivated land area were the four most significant factors. The proportion of government expenditure on agriculture support to total expenditure was a negative influence, whereas the other three significant factors had a positive influence on agricultural output. This study highlights about the most significant factors affecting the agricultural development of impoverished mountainous regions in China.  相似文献   

11.
Climate change affected the agricultural expansion and the formation of farming-grazing transitional patterns during historical periods. This study analyzed the possible range of the boundary shift of the potential suitable agriculture area in the farming-grazing transitional zone in the northeastern China during the 20th century. Based on modem weather data, 1 km-resolution land cover data, historical climatic time series, and estimation by using similar historical climatic scenes, the following was concluded: 1) The climate conditions of suitable agriculture areas in the farming-grazing transitional zone in the northeastern China between 1971 and 2000 required an average annual temperature above 1℃ or ≥ 0℃ accumulated temperature above 2500℃-2700℃, and annual precipitation above 350 mm. 2) The northern boundary of the potential suitable agriculture area during the relatively warmer period of 1890-1910 was approximately located at the position of the 1961-2000 area. The northern boundary shifted back to the south by 75 km on average during the colder period of the earlier 20th century, whereas during the modem warm period of the 1990s, the area shifted north by 100 km on average. 3) The western and eastern boundaries of the suitable agricul~re area during the heaviest drought periods between 1920s and 1930s had shifted northeast by 250 km and 125 km, respectively, contrasting to the boundaries of 1951-2008. For the wettest period, that is, the 1890s to the 1910s, the shift of western and eastern boundaries was to the southwest by 125 km and 200 km, respectively, compared with that in the 1951-2008 period. This study serves as a reference for identifying a climatically sensitive area and planning future land use and agricultural production in the study area.  相似文献   

12.
On the basis of the study on areal differentiation of the natural environment of oasis agriculture ecosystems in the Shiyang River Basin, this paper comparatively analyzes the natural productivities, water economic benefits, production efficiency, ecological stabilities and developmental conditions of the Wuwei Oasis agricultural ecosystem in the middle reaches of the river basin and the Minqin Oasis agricultural ecosystem in the lower reaches. Under a same management level and investment of . material and energy, primary productiveness and economic benefits of the former are higher than those of the latter. Construction directions of Wuwei and Minqin oases should be different in order to alleviate the water- use contradiction between the middle and lower reaches. The construction objective of Wuwei Oasis should be efficient irrigated farming production system and Minqin Oasis should become a mixed forestry-pastoral-farming ecosystem taking ecological protection as its major function.  相似文献   

13.
REGIONAL DIFFERENCES OF ECONOMIC DEVELOPMENT OF THE CHANGJIANG RIVER VALLEY ChenGuoJie(陈国阶)(ChengduInstituteofMountainDisaste...  相似文献   

14.
The Hexi Corridor is an important base of agriculture development in Northwest China. According to recent statistics, there are 65.94×108m3 of water resources available in the Hexi Corridor. At present, net consumption in development and utilization is 43.33×108m3. Water supply and demand reach a balance on the recent level of production, but loss of evaporation and evapotranspiration is as much as 25.69×108m3. So net use efficiency of water resources is 59%. Based on analyzing balance between water and land considering ecological environment at present, there exists the serious water shortage in the Shiyang River system where irrigation lands have overloaded. There is a comparative balance between supply and demand of water resource in the Heihe River system; and the Sule River system has some surplus water to extend irrigation land. Use of agriculture water accounts for 83.3% and ecological forest and grass for 6.9%. The Hexi Corridor still has a great potential for water saving in agriculture production. Water-saving efficiency of irrigation is about 10% by using such traditional technologies as furrow and border-dike irrigation and small check irrigation, and water-saving with plastic film cover and techniques of advanced sprinkler and drip/micro irrigation etc. cansave more than 60% of irrigated water. Incremental irrigation area for water-saving potential in the Hexi Corridor has been estimated as 56% – 197% to original irrigation area. So the second water sources can be developed from water saving agriculture in the Hexi Corridor under Development of the Western Part of China in large scale. This potential can be realized step by step through developing the water-saving measures, improving the ecological condition of oasis agriculture, and optimizing allocation of water resources in three river systems. Foundation item: Under the auspices of the Key innovation Project Engineering of Chinese Academy of Sciences (KZcx-1-10-03) Biography: GAO Qian-zhao (1942 –), male, a native of Changzhou, Jiangsu, Professor and supervisor of Ph. D students. His research interests include hydrology and rational utilization of water resources in the arid zone.  相似文献   

15.
SUTDY ON THE FRAMEWORK SYSTEM OF DIGITAL AGRICULTURE   总被引:10,自引:2,他引:8  
China is a great agricultural country with large population,limited soil resources and traditional farming mode,so the central government has been attaching great importance to the development of agriculture and put forward a new agricultural technology revolution-the transformation from traditional agricultrure to modern agriculture and from exten-sive farming to intensive farming,Digital agriculture is the core of agricultural informatization.The enforcement of digital agriculture will greatly promote agricultural technology revolution.two agricultural transformations and its rapid develop-ment,and enhance China‘s competitive power after the entrance of WTO.To carry out digital agriculture,the frame sys-tem of digital agriculture is required to be studied in the first place,In accordance with the theory and technology of digi-tal earth and in combination with the agricultural reality of China,this artile outlines the frame system of digital agricul-ture and its main content and technology support.  相似文献   

16.
Thethreeriverarea(themiddledrainageareaoftheYarlungZangboRiverbetweenitstributariesoftheLhasaRiverandtheNyangquRiver)isaneco...  相似文献   

17.
China is facing the three major agroenvironment problems, which include: chemical pollution, abnormal ecological balance and natural resource deterioration. These environment problems have depleted part of the comprehensive agricultural productivity and hence become a resistance to the further development of agriculture. A number of measures have been taken for controlling over pollution and ecosystem declining. But for the sustainable development the more efforts are suggested to make, including the more stern measures in the population control, adopting the new techniques of saving natural resources and high efficiency, encouraging a frugal life style as well as paying more attentions to the research on the agricultural environment protection.  相似文献   

18.
Currently, the agricultural growth in developed countries mainly relies on the improvement of productivity, which is also the target for China. Accordingly, the purpose of this study was to describe the spatial-temporal evolution pattern of agricultural productivity, to reveal changes in total factor productivity in 2000–2010, and analyze the impact of these changes in northwestern Sichuan plateau, China. Using data envelopment analysis (DEA) and the Malmquist Index, an in-depth study was conducted on agricultural productivity and changes in total factor productivity of 31 counties in northwestern Sichuan plateau. Results indicated that: (1) geographically, counties with optimal efficiency were mainly located in the north of northwestern Sichuan plateau and those with the lowest efficiency, in the south; (2) relative to pure technical efficiency, scale efficiency was the dominant factor in determining agricultural productivity; (3) the redundancy rate of input factors in 2010 was slightly lower than that in 2000, thereby indicating an improved utilization of input factors to a certain extent and a great potential for further improving such utilization; (4) during the 2000–2010 period, the agricultural total factor productivity had an average annual growth rate of 8.3%, but the growth rates in various regions differed widely; (5) technical progress was the dominant factor promoting the improvement of total factor productivity in agriculture. The disparities in spatial distribution may be due to the differences of natural conditions, former level agricultural productivity between counties. The findings are valuable for the government to make sustainable development policies for agriculture and improving agricultural development in northwestern Sichuan plateau.  相似文献   

19.
The goal of land consolidation in China is still to develop agricultural production. The study of landscape effects of land consolidation projects (LCPs) faces many difficulties because of the lack of government's interest and data. This paper, taking Tianmen City of Hubei Province in Central China as an example, presents a methodology for analyzing landscape effects of LCPs by GIS and Fragstats3.3. It describes landscape effects with indexes of Patch Density (PD), Largest Patch Index (LPI), Landscape Shape Index (LSI), Interspersion and Juxtaposition Index (IJI), Aggregation Index (AI), and Shannon's Diversity Index (SHDI), showing more regular shape, simpler structure and less habitat diversity after LCPs. It computes ten landscape indexes of four categories of patches including Cultivated Land, Road, Water Channel, and River and Pond. The indexes show that 1) cultivated land becomes more fragmental in patch area, less irregular in patch shape and more concentrated in block; 2) the transport capacity of roads and irrigation and drainage capacity of water channels have been improved; 3) the landscape change of river and pond can be summarized as decreasing scale, more regular shape, reducing connectivity and diversity of the class. LCPs can facilitate agricultural production as well as protect cultivated land and food security. However, it is doubted that the increase of cultivated land from LCPs results from the reducing in landscape diversity of water area.  相似文献   

20.
硫酸盐气溶胶对长江中下游夏季降水年代际转型的影响   总被引:1,自引:0,他引:1  
为了研究人为硫酸盐气溶胶增长对1970年代末长江中下游夏季降水年代际转型的影响,使用全球气候模式(GFDL—AM2),对硫酸盐直接气候效应进行了模拟。结果表明,硫酸盐气溶胶增长引起的降水年代际变化与观测到的降水转型有很好的时空一致性;观测中包括副热带高压西伸南移、中国东部近地面异常北风等夏季风年代际减弱信号以及对应的垂直温度、上升运动分布等均能很好地被模式再现。机制上,硫酸盐气溶胶通过引起负辐射强迫,造成中国中东部的大部分地区地面到对流层中层降温,海陆热力对比减小,使东亚夏季风减弱,雨带容易在长江中下游停留,从而导致该区域降水增多。于是,硫酸盐气溶胶增多对长江中下游降水年代际转型有重要贡献。  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