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1.
Cultivated land protection (CLP) entered the new era of macro administration in 1999 in China. This paper presents a holistic analysis of cultivated land use change concerning the three goals of the CLP, i.e., grain security, ecological security and harmonizing regional development. Farmers’ willingness to grow grain has been the key factor in safeguarding grain security. Grain-for-green policy has contributed to improving ecological state especially in the western provinces. Effects of the land macro-control of the CLP on harmonizing regional development were significant. Moreover, cultivated land use change in 1999-2007 points out the way of the evolving policy in the future. From the viewpoint of normative concept of multifunctionality, we discuss development of the three land functions, i.e., production function, environmental function and carrier function. Finally, we propose to emphasize multifunctional land management based on regional differences to promote transition of the CLP.  相似文献   

2.
Understanding the driving forces and mechanism of land use change is a key issue in land change science, and has received much attention over the past 30 years. While many driving forces have been identified, the mechanism of land use change is still unclear, mainly because of limited knowledge of the underlying motivation for land use change. Traditionally, the underlying motivation for land use change was ascribed to people's pursuit of satisfying their own demands or that of profit maximization. However, those theoretical hypotheses combine all productive factors without highlighting certain predominant factor, in this paper, a case study was conducted on the variation of land productivity, capital productivity and labor productivity in agricultural land use in Xinjiang Uygur Autonomous Region of China. The case study revealed that only labor productivity presented a long-term increasing trend in regional cotton and grain production. This result implies that people's pursuit of increasing labor pro- ductivity is probably the underlying motivation for land use change. Additional details identi- fied in agricultural and non-agricultural land use in China support the above implication. As labor productivity is a determinant of people's living standards, increasing labor productivity means improving people's living standards. Therefore, it is concluded that land use change results from people's pursuit of increasing labor productivity in a changing environment.  相似文献   

3.
China is a disaster prone country, and a comprehensive understanding of change of disasters is very important for China’s agricultural development. In this study, statistical techniques and geographic information system tools are employed to quantify the main agriculture disasters changes and effects on grain production in China during the period of 1990–2011. The results show that China’s grain production was severely affected by disasters including drought, flood, hail, frost and typhoon. The annual area covered by these disasters reached up to 48.7×106 ha during the study period, which accounted for 44.8% of the total sown area, and about 55.1% of the per unit area grain yield change was caused by disasters. In addition, all of the disasters showed high variability, different changing trends, and spatial distribution. Drought, flood, and hail showed significantly decreasing trends, while frost and typhoon showed increasing trends. Drought and flood showed gradual changes and were distributed across the country, and disasters became more diversified from north to south. Drought was the dominated disaster type in northern China, while flood was the most important disaster type in the southern part. Hail was mainly observed in central and northern China, and frost was mainly distributed in southern China. Typhoon was greatly limited to the southeast coast. Furthermore, the resilience of grain production of each province was quite different, especially in several major grain producing areas, such as Shandong, Liaoning, Jilin and Jiangsu, where grain production was seriously affected by disasters. One reason for the difference of resilience of grain production was that grain production was marginalized in developed provinces when the economy underwent rapid development. For China’s agricultural development and grain security, we suggest that governments should place more emphasis on grain production, and invest more money in disaster prevention and mitigation, especially in the major grain producing provinces.  相似文献   

4.
The metropolitan resources comprehensive efficiencies (also called comprehensive technical efficiency, short for CTE, thereafter), change trends and causes are investigated using DEA and Malmquist index models, respectively, in China during the period 1990–2006. Firstly, the DEA model results show that the metropolitan CTE was just fair to middling with the characteristics of almost declining from the Eastern Coastal to Western China, and only few metropolises were DEA efficient. Secondly, the results also show that the PTE was correlated with the urban population sizes of metropolises negatively, and the SE correlated positively with the urban population sizes of metropolises in 1990, 2000 and 2006, that is, with urban population sizes getting larger the corresponding PTE was decreasing accordingly, and the SE was increasing consequently and the increasing rate was smaller with the scale increase. Thirdly, the influencing factors of metropolitan efficiency were SE and PTE in 1990 and 2000, respectively. But the PTE became the predominant influencing factor with the rapid expansions of built-up areas and population scales of metropolises in 2006. Fourthly, the Malmquist index results show that the CTE change trends were increasing weakly, the technological change trends were declining, and the TFP change trends were declining obviously during 1990–2006, in which they were all increasing during the sub-period 1990–2000, and all decreasing during the sub-period 2000–2006. Fifthly, the Malmquist index results also demonstrate that the CTE change trend was increasing weakly in the Eastern Coastal China, declining in Central China, and declining evidently in Western China. And with the urban population size increasing the increasing trends of SE became weaker and weaker. And the main causes for the CTE being not too high and its change trends and TFP change trends being increasing weakly lie mainly in the technological degeneracy and PTE change trends declining significantly during 2000–2006. Finally, the analyses show that the China’s metropolitan population boom and the rapid spread of built-up area had really caused their resources efficiency losses.  相似文献   

5.
21世纪初中国土地利用变化的空间格局与驱动力   总被引:33,自引:15,他引:18  
Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the "Grain for Green" policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of "Western Development", "Revitalization of Northeast", coupled with rapidly economic development during this period.  相似文献   

6.
Farmland marginalization has become the main trend of land-use change in the mountainous areas of China. Using annual survey data of major agricultural production costs and earnings at national and provincial levels in China, this study aims to analyze the reasons and mechanism behind farmland marginalization in mountainous areas. We find that farmers on plains are able to reduce their per mu labor input effectively through intensive use of agricultural machinery, which has minimized the impact of the increase in labor price. However, it is extremely challenging for farmers in mountainous areas to use the same method owing to the rough terrain. Thus, per laborer farming area in these areas has increased relatively slowly, causing a widening gap in agricultural labor productivity between the two regions. With the rapid rise in labor costs since 2003, the marginalization of cultivated land in mountainous areas is evident. In 2013, the net profit of agricultural production in mountainous China fell below zero. Since 2000, the land-use and land-cover change in these areas was characterized by the reduction of farmland area, reforestation, and the enhancement of the NDVI value. The high correlation between the NDVI change rate and the ratio of change in farmland(r = –0.70) and forest(r = 0.91) in mountainous areas at provincial level further attests to the trend of farmland marginalization there. Finally, we summarize the mechanism of such marginalization against the backdrop of the rapid increase in the opportunity cost of farming and the rapid fall of agricultural labor forces in mountainous areas. This study contributes to a deep understanding of the development process of farmland marginalization and abandonment as well as forest transition in Chinese mountainous areas.  相似文献   

7.
Changes in rice production in Southern China are crucial to national food security. This study employed Landsat images to map the distributions of paddy rice-cropping systems in Southern China in 1990 and 2015. The impact of rice multiple cropping index changes on grain production capacity was then evaluated. Three important results were obtained for the 1990 to 2015 study period. First, the multiple cropping index for rice decreased from 148.3% to 129.3%, and 253.16×10~4 ha of land area was converted from double-cropping to single-cropping rice, termed "double to single". The area with the most dramatic changes is in the Middle-Lower Yangtze Plain. The rice-cropping system distribution in Southern China showed a change from north to south with double-cropping rice shrinking and single-cropping rice expanding. Second, the "double to single" conversion led to a reduction of 6.1% and 2.6% in rice and grain production, respectively. Hunan and Jiangxi Provinces, located in the main rice producing areas, and Zhejiang, which has shown better economic development, exhibited large reductions in rice production due to the "double to single" conversion, all exceeding 13%. Third, the grain production capacity of converted "double to single" paddy fields is equivalent to that of 223.3 × 10~4 ha of newly reclaimed cultivated land, which is 54% of the total newly cultivated land reclaimed through the 2001–2015 land consolidation project. It is also 1.7 times the target goal for newly cultivated land in the national land consolidation plan for 2016–2020. Making full use of the converted "double to single" paddy fields can save 167.44 billion yuan in newly reclaimed cultivated land costs. Therefore, instead of pursuing low-quality new arable land, it is better to make full use of the existing high-quality arable land. Based on these results, the government should change the assessment method for cultivated land balance, and incorporate the sown area increased by improving the multiple cropping index into the cultivated land compensation indicator.  相似文献   

8.
Suitable spatial morphology of cultivated land is a basic requirement for sustaining agricultural economic development in mountainous areas. Coordinated development efficiency of cultivated land spatial morphology and agricultural economy(CECA) is of great practical significance to measure the efficiency of cultivated land use, and thereby promote regional rural revitalization. However, few studies to date have focused on coordinated development efficiency between cultivated land use and agricul...  相似文献   

9.
In order to advance land use and land cover change(LUCC) research in Nepal, it is essential to reconstruct both the spatiotemporal distribution of agricultural land cover as well as scenarios that can explain these changes at the national and regional levels. Because of rapid population growth, the status of agricultural land in Nepal has changed markedly over the last 100 years. Historical data is used in this study, encompassing soils, populations, climatic variables, and topography. Data were revised to a series of 30 m grid cells utilized for agricultural land suitability and allocation models and were analyzed using a suite of advanced geographical tools. Our reconstructions for the spatiotemporal distribution of agricultural land in Nepal reveal an increasing trend between 1910 and 2010(from 151.2 × 10~2 km~2 to 438.8 × 10~2 km~2). This expanded rate of increase in agricultural land has varied between different eco, physiographic, and altitudinal regions of the country, significantly driven by population changes and policies over the period of this investigation. The historical dataset presented in this paper fills an existing gap in studies of agricultural land change and can be applied to other carbon cycle and climate modeling studies, as well as to impact assessments of agricultural land change in Nepal.  相似文献   

10.
During the last decade of the 20th century, extensive conversion in agricultural land use took place in Northeast China. The goal of this study is to ascertain its spatial distribution and regional differentiation, determine its causes, and analyze its environmental impact, Especially we attempt to elucidate how institutional constraints have facilitated the change at a time of agrarian restructuring when newly emerging free market was hybridized with the former planned economy. Information on six categories of land use was mapped from interpretation of Landsat TM images recorded in 1990,1995 and 2000. Most of land use changes took place during the first half of the decade, coinciding with abrupt and chaotic changes in government directives. Farmland was changed mainly to woodland,water body and built-up areas while woodland and grassland were converted chiefly to farmland.Spatially, the change from farmland to woodland was restricted to the west of the study area. The change from grassland to farmland took place in the grazing and farming interlocked west. These chaotic and occasionally conflicting changes were largely caused by lack of stability and consistency in agricultural land use policies promulgated. They have exerted adverse impacts on the local environment, including land degradation, increased flooding, and modified climate regime.  相似文献   

11.
This paper attempts to explore the temporal and spatial nature of the marginal revenue of land, total factor productivity (TFP) change and its three components: technical change (TC), technical efficiency change (TEC) and scale efficiency change (SEC) as seen in Chinese agricultural production from 1995 to 1999. Based on county-level data, the study utilized both stochastic frontier and mapping analyses methods. The results show that growth in the marginal revenue of land was diverse across various regions, where most gain occurred in eastern coastal zone, while loss was in Northwest and North China. China has experienced moderate decreases in annual TFP change (-0.26%) with considerable regional variations. Specifically, the administrative intervention in grain production and the deterioration of the agricultural technology diffusion system led to a moderate drop in annual TFP change. County-level mapping analyses took into account interregional variances in TFP and its components. Regarding components of TFP, TEC differences explain the majority of regional dispersions in TFP. As developed areas in China, the Huang-Huai-Hai region and the Beijing-Tianjin-Tangshan economic zone face the challenges of land conversion and grain security amidst the process of urbanization.  相似文献   

12.
中国经济效率和全要素生产率的空间分异及其影响   总被引:9,自引:3,他引:6  
运用Malmquist 指数模型测度了1990-2009 年中国省域的经济效率和全要素生产率, 并对其影响因素进行了分析。研究发现:在这20 年间, 中国的全要素生产率在全国层面及不同空间尺度的区域层面呈现波动状态, 且全要素生产率平均下降了1.35%。按照东、中、西和东北进行划分, 只有东部地区平均全要素生产率得到改善, 平均上升了2.37%, 上升的原因在于技术进步率显著改善;其余区域的全要素生产率均呈现不同程度的下降, 其中, 中部地区下降最多, 平均下降了4.45%;西部地区和东北地区的全要素生产率的平均增长率分别下降了2.78%和1.84%;原因在于中国技术效率、纯技术效率和规模效率的增长率在大部分年份出现了下降。从全要素生产率的影响因素上看, 经济集聚、人力资本、信息化、基础设施、经济开放度及制度因素对全要素生产率的影响为正;产业结构、政府干预和土地投入对全要素生产率的影响为负;但基础设施水平对全要素生产率的影响在统计学上并不显著。文章讨论了主要结果赋予的政策含义。  相似文献   

13.
朱会义 《地理学报》2013,68(8):1029-1037
土地利用变化的动力因子和动力机制是土地科学研究的核心问题。这一问题近30年来得到前所未有的关注,相关研究成果不断涌现,但是这些成果主要关注自然因子和社会经济因子等外在因素,却没有充分重视土地利用变化中蕴含的内在目标和由此派生的内在动力,客观上导致土地利用变化动力机制研究一直难以深入。本文以新疆地区为案例区,以土地、资本和劳动等生产要素生产效率变化为切入点,利用趋势拟合方法,分析了区域土地利用变化过程中要素产出效率的变动规律。结果显示,无论是近10年还是近30年区域棉花生产中,以及近30年区域粮食生产中,只有劳动生产率呈长期增长趋势。这一结果意味着人们对劳动生产率的追求可能是土地利用变化的内在动力。据此,进一步讨论了人们追求劳动生产率增长的原因及其与追求利润最大化等目标的关系,提出了"土地利用变化是人们在变化环境下不断追求劳动生产率增长的结果"这样一个观点。  相似文献   

14.
中国粮食安全脆弱区的识别及空间分异特征   总被引:8,自引:2,他引:6  
殷培红  方修琦 《地理学报》2008,63(10):1064-1072
从粮食获取能力和粮食安全保障阈值的角度, 综合考虑粮食供需平衡、粮食安全储备、 经济补偿能力等因素, 构造综合评价指标-粮食安全保障的财政压力水平, 以粮食安全保障 费用不超过地方财政收入水平的25%作为可接受水平, 共识别出6 个不同类型的粮食安全区。 在没有重大灾害事件发生和现有粮食播种面积不变的前提下, 全国有14.5%的县(市) (1 级和3 级粮食安全区) 能够通过粮食生产或者经济补偿能力保障小康水平的粮食安全。全国29.4% 的县(市) 属于2 级粮食安全区, 其中57%的地区是中国的主要余粮区, 约占全国主要余粮区 中的72%, 因财政收入低、人口密度大, 不能负担庞大的小康水平粮食安全储备费用。中国 粮食安全最脆弱的地区(6 级区) 占全国县(市) 总数的30%, 不具备温饱水平粮食生产能力和 经济补偿能力, 主要包括两类地区: ① 夏季季风区边缘地带的农牧交错带及秦岭地区, 以及 南方贫困的丘陵地区属于“资源型粮食短缺地区”; ② 广西、广东南部以及东部沿海地区等 富裕地区属于“结构性粮食短缺地区”, 过低的粮食自给率已影响到粮食安全应急保障能力。  相似文献   

15.
21世纪初中国土地利用变化的空间格局与驱动力分析   总被引:99,自引:5,他引:94  
在全球环境变化研究中.以土地利用与土地覆盖动态为核心的人类一环境耦合系统研究逐渐成为土地变化科学(LCS)研究的新动向.基于覆盖中国21世纪初5年间隔的遥感卫星数据获取的1 km网格土地利用变化空间信息.依据近5年土地利用变化区域分异的显著特征,以及自然地理、经济发展与国家宏观政策因素综合考虑.设计针对21世纪初5年新的中国土地利用动态区划图,揭示土地利用变化的空间格局与驱动因素.总体上.21世纪初5年中国处于土地利用快速变化期,黄淮海平原、东南沿海地区与四川盆地城乡建设用地显著扩张,占用大规模优质农田,导致南方水田面积明显减少:西北绿洲农业发展与东北地区开垦导致北方旱地面积略有增加:受西部开发"生态退耕"政策的影响中西部地区林地面积显著增加,国家退耕还林还草政策成效明显,对区域土地覆盖状况的改善产生积极的影响:这一时段国土开发与区域发展战略的实施,包括"西部大开发"、"东北振兴"等国家重大政策,加之快速的经济发展是该阶段土地利用变化格局形成的主要驱动因素.  相似文献   

16.
碳约束下中国县域尺度农业全要素生产率比较研究   总被引:4,自引:1,他引:3  
揭懋汕  郭洁  陈罗烨  雪燕  薛领 《地理研究》2016,35(5):898-908
基于2183个县级单元,利用SFA方法对1992-2011年碳约束下中国县域农业生态TFP及其分解项进行研究,并与不考虑碳排放的传统TFP进行比较。结果表明:第一,农业生态TFP年平均增长4.47%,低于传统TFP,但两者差距有缩小的趋势,2011年前者超过后者。第二,农业生态TFP贡献了中国农业总产值增长的54.9%,比传统TFP的份额低了3.6%,要素投入贡献为45.1%。第三,分解项上,前沿技术进步率是农业生态TFP的主要驱动因素,也是生态TFP与传统TFP差距缩小的动因。第四,空间分布上,生态TFP大于传统TFP的地区主要分布在胡焕庸线东南的地区;西部由于生态TFP和传统FTP都较低,呈现出“双重恶化”现象;除了嵊泗县以外,农业生态TE和TEC均低于传统TE和TEC,生态FTP也整体低于传统FTP。  相似文献   

17.
汪言在  刘大伟 《地理科学》2017,37(12):1942-1952
采用全要素生产率F?re-Primont指数,分析了纳入气候要素和非纳入气候要素2种情景的重庆市全要素生产率增长时空变化。结果表明:相比于非纳入气候要素情景,纳入气候要素的重庆市农业全要素生产率增长数值尽管偏低,但具有显著的空间分异,且能较好的反映农业技术进步与极端干旱事件对农业生产的影响。重庆市农业全要素生产率增长的主要驱动力来自技术进步;而增长阻碍主要来自剩余混合效率,因此应加强农业结构性改革,进一步改善农业生产投入产出结构。受农业发展基础和生产结构的影响,重庆市农业全要素生产率增长较大的地区集中在西部区县;而增长偏低地区集中在主城区。 2006年重庆极端干旱事件对农业全要素生产率增长产生显著影响,导致农业全要素生产率增长在2006年明显偏低;各区县受极端干旱事件的影响不同,应根据各区县农业资源条件,有针对性提出适应气候变化的农业生产策略。  相似文献   

18.
农业地理学发展述要   总被引:3,自引:0,他引:3  
本文以动态观点,提纲挈领地论述我国以及西欧、北美和苏联等主要国家近代农业地理学的发展过程。主要的传统研究是以地域为单元来探讨农业生态、土地利用、粮食生产与供应,农业地域类型和农业区划,编写区域农业地理志和农业图集等。作者认为农业地理学是典型的边缘科学,它是农业科学又是地理科学的组成部分。它的主要研究对象是农业经济活动的地域系统,它的形成过程,结构特征和发展规律。根据我国现代化建设的要求,在90年代我国农业地理学将着重研究:农业发展的资源基础,人口与粮食平衡,农业生产和劳动力的结构变化,农村工业化和贫困山区脱贫致富问题。  相似文献   

19.
中国粮食生产的区域格局变化及东北商品粮基地的响应   总被引:58,自引:7,他引:51  
程叶青  张平宇 《地理科学》2005,25(5):513-520
依据近10年的统计数据和实地调研资料,运用区域差异分析方法,对中国粮食生产的区域格局变化特征及其规律进行探讨,研究表明:中国粮食产量总体呈增长态势,年均增长率为3.43%;粮食生产重心进一步由南方向北方和由东部向中部推移,北方和中部地区成为新的增长中心;粮食生产地域变化的差异明显,南北绝对差异和相对差异变化较大,八大产区和省区间变化较小。农业生产条件、技术、宏观经济环境和土地利用方式变化是粮食生产地域格局变化的主要原因。东北作为国家粮食安全战略性基地,应对全国粮食生产的地域变化趋势,必须加强商品粮基地建设。通过农业生态环境建设、农业结构调整、商品粮基地空间布局优化等举措,促进粮食生产,保障国家粮食安全。  相似文献   

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