中国食物消费随人口结构变化分析

中国目前正在经历快速的人口年龄结构调整,其必会对中国食物消费产生巨大的影响。该文利用中国健康与营养调查(China health and nutrition survey,CHNS)数据,对中国不同年龄居民的消费特征进行了分析,在此基础上,根据生命周期理论与Leslie人口模型,预测2030年前中国各年龄的人口规模,进而判断人口年龄结构变化对中国主要食物消费量的影响。研究结果显示:1)不同年龄段居民的不同类别的食物消费规律明显,大致可分为4种类型:倒"U"型曲线消费(口粮、水产品、白酒)、"U"型曲线消费(牛奶)、阶段性直线消费(肉类3阶段消费规律、禽类2阶段消费规律)、无差异消费(禽蛋)。2)人口年龄结构对中国食物消费总量产生了明显的影响,包括正向影响(口粮、水产品、白酒)、负向影响(肉类、禽类)、先负后正影响(牛奶)、无明显影响(禽蛋)。3)在影响程度上,中国人口年龄结构的演变对肉类、禽类消费量的负向影响最为明显,至2030年,分别达到4.9%与11.2%的程度,对白酒的正向影响也达到8.2%的程度。对口粮、水产品、牛奶的影响程度相对较小,而对禽蛋几乎没有影响。由此可见,人口年龄结构的变化会使中国居民肉类消费需求增长及由此带来的粮食需求压力趋缓。

华北平原农户主动退耕冬小麦的影响因素模型分析及政策启示

为揭示华北平原农户主动退耕冬小麦的现状及其影响因素,借助河北省沧县农户问卷调查数据,构建农户土地利用决策理论模型与多层二项logit模型。结果表明:1)案例区农户主动退耕冬小麦现象已较为普遍,2000年以来冬小麦退耕面积占耕地总面积的比例达28.18%;2)地块、农户和村庄3个层次在解释农户土地利用决策方面均发挥显著作用,其解释程度分别为52.1%、17.5%和30.4%;3)地块层次的土地质量、灌溉水源和地块面积在1%或5%水平下显著影响农户冬小麦退耕决策,且土地质量低下、灌溉水源稳定性较差、面积较小的地块更有可能退耕冬小麦;4)农户层次的平均务工收入、地均务农劳动力数量、受教育程度、农机设备和地块破碎度在5%或10%的水平发挥显著影响,且地均务农劳动力数量少、平均务工收入和地块破碎度高、农业决策者受教育程度高且不具备农机设备的农户退耕冬小麦的概率更高;5)村庄层次灌溉用电单价通过了5%的显著性检验,且灌溉用电单价越高时,农户越有可能发生冬小麦退耕行为。在此基础上,提出相关政策建议如下:农户主动退耕冬小麦背景下推行土地休耕制度须精准,应以严格的冬小麦种植摸底调查监测为前提,还应结合农村集体新型产业发展、农业水价综合改革等措施推进制度落实;同时,应加强地表水资源的合理配置与管理,稳定与适度发展地表水灌溉的小麦面积,为实现土地休耕与口粮安全"双赢"做出贡献。

重庆典型山区耕地资产贬值特征及其发生机理

耕地边际化是山区一种典型的土地利用现象,厘清其表现特征及机理对实现土地资本增值和乡村振兴具有重要价值。基于2012和2018年重庆典型山区901份农户问卷及农产品成本收益资料,该文揭示了耕地资产价值的演变特征,并构建Probit模型识别其驱动因素与发生机理。结果表明:1)近年来,案例区耕地资产价值不断下降,单位面积玉米收益由正转为亏本,主要农作物加权净收益从2012年的1384.50元/hm^2降至2018年的252.30元/hm^2;耕地租金从1577.45降至361.65元/hm^2,同时零租金流转比例从71.09%升至82.21%,说明研究区耕地资产价值正处于下滑阶段。2)地块面积、与家庭距离、地块质量和土地细碎化是耕地零租金流转的关键因素,而务农机会成本上升是根源。耕地资产贬值的机理是,城镇化推高了劳动力成本,农业利润不断下降直至亏本,耕地资产出现贬值。期间,山区闲置或抛荒的土地资源变得愈发丰富,政府应合理引入资本,充分挖掘相对富裕的土地资源,以实现土地资本增值和发展当地经济。此外,政府应停止在山区大规模的开垦耕地,但可通过土地整治适当补充耕地,避免公共财政资金浪费和破坏生态环境。

China’s Potential of Grain Production Due to Changes in Agricultural Land Utilization in Recent Years

The changes in utilization of agricultural land have gradually grown into one of the major factors impacting grain output in China. This study explores the various components of agricultural production in China from the land utilization perspective, involving changes in grain production per unit area, multi-cropping index, and adjustment of agricultural structure. Compared with the record values, different research methodologies are used to analyze the po- tential of above three components. The results indicate that grain production potential of 65.68×109kg was unexploited in 2006, in which 45.8×109kg came from the restructuring in agriculture. So we can infer that the reduction of grain production in China could be primarily attributed to agricultural restructuring in recent years. So the productive poten- tial can be fully restored by increasing agricultural investment, or recovering agricultural structure in favorable condi- tions. So we can say that China’s current condition of food security is good.

Spatial and Temporal Variability of Farm Size in China in Context of Rapid Urbanization

During the last 30 years, China has witnessed rapid economic growth and dramatic urbanization, with about 1.2 x 107 rural 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 cen- sus 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 fac- tors （agricultual land system, household registration, stable clan system, and farmland loss）.

Inter-provincial Differences in Rice Multi-cropping Changes in Main Double-cropping Rice Area in China: Evidence from Provinces and Households

Since the early 1980 s, the multi-cropping index for rice has decreased significantly in main double-cropping rice area in China, which is the primary double-cropping rice(DCR) production area. This decline may bring challenges to food security in China because rice is the staple food for more than 60% of the Chinese population. It has been generally recognized that rapidly rising labor costs due to economic growth and urbanization in China is the key driving force of the ‘double-to-single' rice cropping system adaption. However, not all provinces have shown a dramatic decline in DCR area, and labor costs alone cannot explain this difference. To elucidate the reasons for these inter-provincial distinctions and the dynamics of rice cropping system adaption, we evaluated the influencing factors using provincial panel data from 1980 to 2015. We also used household survey data for empirical analysis to explore the mechanisms driving differences in rice multi-cropping changes. Our results indicated that the eight provinces in the study can be divided into three spatial groups based on the extent of DCR area decline, the rapidly-declining marginal, core, and stable zones. Increasing labor cost due to rapid urbanization was the key driving force of rice cropping system adaption, but the land use dynamic vary hugely among different provinces. These differences between zones were due to the interaction between labor price and accumulated temperature conditions. Therefore, increasing labor costs had the greatest impact in Zhejiang, Anhui, and Hubei, where the accumulated temperature is relatively low and rice multi-cropping index declined dramaticly. However, labor costs had little impact in Guangdong and Guangxi. Differences in accumulated temperature conditions resulted in spatially different labor demands and pressure on households during the busy season. As a result, there have been different profits and rice multi-cropping changes between provinces and zones. Because of these spatial differences, regionally appropriate policies that provide appropriate subsidies for early rice in rapidly-declining marginal zone such as Zhejiang and Hubei should be implemented. In addition, agricultural mechanization and the number of agricultural workers have facilitated double-cropping; therefore, small machinery and agricultural infrastructure construction should be further supported.

Environmental evolution in the salt-water intrusion area south of Laizhou Bay since late Pleistocene

The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses of pollen, foraminifera and grain size composition based on ^14C and luminescence dating from two sediment cores were performed for the purpose of understanding the salt-water intrusion in the coastal plain of Laizhou Bay from the perspective of environmental evolution since late Pleistocene. It could be classified into seven evolution stages since 120 kaBP： 120-85 kaBP was a transition period from cold to warm; 85-76 kaBP was a period with warm and wet climate having swamp lakes developed in the lower reaches of the Weihe River, south coastal plain of Laizhou Bay; 76-50 kaBP was characterized by grassland vegetation and coarse sediments in terrestrial environment, which was the early stage of Dali Ice-Age; 50-24 kaBP was a period with alternate sea deposition in the south coastal plain of Laizhou Bay; 24-10 kaBP was the late stage of Dali Ice-Age with coldest period of Quaternary, the south coastal plain of Laizhou Bay was dry grassland and loess deposition environment; 10-4 kaBP was another warm and wet climate period, sea level was high and regressed at 4 kaBP; and has been the modern sedimentary environment since 4 kaBP. Among the three warm stages, including 85-76 kaBP, 50-24 kaBP and 10-4 kaBP, corresponded to late Yangkou, Guangrao and Kenli seawater transgression respectively. The duration of the latter one in south coastal plain of Laizhou Bay was longer than that in west coast of Bohai Sea and east coast of Laizhou Bay. The three periods of seawater transgression formed the foundation of salt-water intrusion in this area.

Study of the intensity and driving factors of land use/cover change in the Yarlung Zangbo River, Nyang Qu River, and Lhasa River region, Qinghai-Tibet Plateau of China

Land use/land cover(LULC) is an important part of exploring the interaction between natural environment and human activities and achieving regional sustainable development. Based on the data of LULC types(cropland, forest land, grassland, built-up land, and unused land) from 1990 to 2015, we analysed the intensity and driving factors of land use/cover change(LUCC) in the Yarlung Zangbo River,Nyang Qu River, and Lhasa River(YNL) region, Qinghai-Tibet Plateau of China, using intensity analysis method, cross-linking table method, and spatial econometric model. The results showed that LUCC in the YNL region was nonstationary from 1990 to 2015, showing a change pattern with "fast-slow-fast" and "U-shaped". Built-up land showed a steady increase pattern, while cropland showed a steady decrease pattern. The gain of built-up land mainly came from the loss of cropland. The transition pattern of LUCC in the YNL region was relatively single and stable during 1990–2015. The transition pattern from cropland and forest land to built-up land was a systematic change process of tendency and the transition pattern from grassland and unused land to cropland was a systematic change process of avoidance. The transition process of LUCC was the result of the combined effect of natural environment and social economic development in the YNL region. This study reveals the impact of ecological environment problems caused by human activities on the land resource system and provides scientific support for the study of ecological environment change and sustainable development of the Qinghai-Tibet Plateau.

中国不同类型耕地撂荒时空分异及其影响因素研究——基于全国346个山区县的调查数据

系统性探寻耕地撂荒现象,有助于因地制宜地稳步拓展农业生产空间。基于全国346个代表性山区县的抽样调查,本文利用空间分析和分层线性模型等方法,系统揭示不同类型耕地撂荒的时序、规模、空间分异特征及其决定因素,以期为分类推进撂荒地治理提供科学依据。研究发现:不同类型耕地的撂荒时间节点存在显著差异,坡耕地、旱作梯田、水作梯田、平地水田和平地旱地依次撂荒,耕作条件较差的耕地更早遭遇撂荒,特别是坡耕地自20世纪80年代起就开始撂荒。目前,26.64%的农户经历过耕地撂荒,撂荒耕地的面积占比达到9.88%,呈现出“南高北低”的空间分布特征。水田撂荒主要集中在东南沿海,而坡耕地和旱地则多发于黄土高原、东南沿海和西南山区。撂荒情况受村落和农户特征影响,这两个层面分别对撂荒变异解释了44.83%和55.17%。从事非农工作、年长及身体状况较差的农户更可能撂荒耕地;同时,遭受野生动物侵害、土地细碎化严重且灌溉条件不佳的区域更易撂荒。劳动力成本的持续上升压缩了农业收益,使得农户种粮收益偏低,旱作梯田甚至面临亏损。因此,撂荒地的治理应聚焦坡耕地和梯田,政府应积极推动土地流转与整治,普及适合丘陵山区的小型机械,以降低耕地经营成本,提高农耕效益。

中国典型山区农业水土资源匹配格局变化——以太行山区、横断山区、黔桂喀斯特山区为例

为了解中国典型山区农业水土资源分布的匹配程度及其格局变化,研究以区域内单位面积耕地拥有的农业水资源量刻画太行山区、横断山区和黔桂喀斯特山区农业水土资源的时空匹配情况。结果表明:①三大山区耕地分布的集中程度较高。太行山区的耕地主要分布在河北境内的北段地区和山西境内的南段地区,横断山区的耕地主要分布在南段地区,喀斯特山区的耕地分布呈现"南北多中部少"的格局。②三大山区农业水资源的分布及变化都主要集中在低海拔地区。太行山区的农业水资源主要分布在山西、河南段,横断山区的农业水资源主要分布在四川境内,喀斯特山区的农业水资源较均匀地分布在广西和贵州境内。③太行山区农业水土资源匹配程度较差,横断山区、喀斯特山区农业水土资源匹配程度较好。2000—2015年间,太行山区中部、横断山区东部、喀斯特山区南部地区的农业水土匹配程度有变好趋势,而太行山区南部、横断山区西南部、喀斯特山区北部地区的农业水土匹配程度有变差趋势。研究时段内,太行山区的水田转旱地情况突出,太行山区也是三大山区中农业水土资源匹配程度最差的,应该关注太行山区的用水压力,重视农田水利设施维护和农田灌溉水有效利用。

中国县域粮食产量的时空格局及其与经济发展的空间关系

粮食是人类赖以生存的基本必需品,为区域经济发展提供了物质基础。研究粮食生产时空格局及其与经济发展的关系,对全面认识当前中国粮食安全,把握粮食生产与区域经济协同发展以及制定差异化的粮食政策有着重要的现实意义。以中国2019个县域为研究对象,基于2000—2017年各县统计数据,借助空间自相关分析、重心转移模型、CGE指数等方法,对中国县域粮食产量的时空格局及其与经济发展的空间关系进行分析。结果表明:(1)中国人均粮食产量的空间格局存在明显的地域分异特点,缺粮区集中在青藏区、黄土高原区和华南区,余粮区集中在东北区、黄淮海区、蒙新区和长江中下游区。(2)中国人均粮食产量变化趋势以增加为主,以东北区和黄淮海区为代表的北方区域增加显著,以长江中下游区和华南区为代表的南方区域降低明显;随着时间的推移,人均粮食产量的空间集聚特征愈加明显,粮食生产地域分工更加清晰。(3)中国人均粮食产量与经济发展重心呈现分离态势,人均粮食产量重心向东北移动,而经济重心向西推进。两者在空间上整体欠平衡,但随着时间的推移,粮食与经济协调性有所改善,改善的区域主要集中在长江中下游区西部、西南区的东部以及黄土高原西部等地。

南方水稻复种指数变化对国家粮食产能的影响及其政策启示

中国南方地区水稻生产的变化对国家粮食安全具有重要影响。本文利用Landsat数据提取1990-2015年南方地区水稻种植制度分布及变化,并分析其对粮食产能的影响。结果表明:①1990-2015年,水稻复种指数从148.3%下降到129.3%,双季稻改种单季稻("双改单")损失的播种面积为253.16万hm^2,区域上以长江中下游地区变化最为突出。南方地区水稻种植制度整体呈现由北向南"双退单进"的变化格局;②1990-2015年,"双改单"导致全国水稻产量减少6.1%,粮食产量减少2.6%。水稻主产区湖南省和江西省以及经济发展较好的浙江省因"双改单"水稻减产幅度较大,均超过13%;③充分利用"双改单"稻田的粮食产能相当于新增耕地223.3万hm^2,为2001-2015年通过土地整治项目新增耕地总量的54%,是2016-2020年全国新增耕地规划目标的1.7倍,可节省约1674.4亿元新增耕地开垦费用。因此,与其追求低质量的"新"耕地,不如充分利用已有的高质量"旧"耕地,政府应转变耕地占补平衡的考核方式,将因提高复种指数增加的播种面积纳入补充指标。

中国梯田撂荒程度及空间格局分异研究

在城镇化和工业化的驱动下,中国丘陵山区耕地逐渐被边际化,耕地撂荒范围也迅速从劣质的坡耕地延展至优质的梯田,大规模梯田撂荒将会引发一系列社会和生态效应,科学评估中国山区梯田的撂荒程度及空间分布将有助于有效地应对耕地撂荒问题。本文通过全国抽样调查的方式对中国梯田的撂荒程度进行了调查,利用获取的中国329个县的560份村问卷测算了中国梯田撂荒规模,并进一步分析了梯田撂荒空间分异特征及驱动因素。结果显示:①全国梯田撂荒现象分布广泛,发生梯田撂荒的村庄占总调查村庄的比例为54%,撂荒面积占梯田总面积的比例达到9.79%;②梯田撂荒程度呈现“南高北低”的特征,南方丘陵山区较为严重,尤以长江中下游地区为最;③梯田撂荒的主要因素可归结为农业劳动力外出务工、梯田耕作机械化程度、灌溉条件、耕作交通条件等。减缓梯田撂荒,应因区精准施策,提高梯田区机械化水平等措施具有普适性,针对质量较差的梯田,可有序“退耕”,对于质量较好的梯田,可采用调整种植结构、加强农业基础设施建设、鼓励流转与规模经营等方式。

耕地资产社会保障功能的空间分异研究--不同农业类型区的比较

在中国人多地少和土地产权二元结构背景下,耕地资源一直是农民的"命根子",其社会保障功能被认为是社会的稳定器,但近年来这一观点受到越来越多的质疑。目前中国农户耕地的社会保障功能还有多大,迫切需要利用详实的数据进行系统性、定量化的测算。基于此,把拥有承包权的耕地看作农户的一项资产,论文选取都市农业区、集约农业区、平原主粮作物区和山地主粮作物区4类典型农业区,实地调查1025户农户家庭,旨在揭示耕地社会保障功能的空间分异规律。结果表明:作为家庭农业的生产资料,耕地投入农业生产所获收益占家庭总收入的比重在各区最高为50%,其中山区不足7%;作为一项养老保障,家庭耕地资产收益对养老需求的贡献率均不足30%,山区甚至不及3%;作为金融抵押品,若以20万元资金需求为例,户均耕地资产可贷款额度均不超过资金需求的20%,而山区仅为1%。现阶段农户耕地资产的社会保障价值已十分微弱,这有助于给出对新时期农村土地保障功能的科学判断。随着城镇化的推进,不同农业类型区农户的耕地收益及资产价值均不断下降,尤其是在农地利用边际化胁迫下的山区,如何减缓山区耕地弃耕撂荒和耕地资产贬值,无疑是乡村振兴战略实施过程中需要重点关注的问题。

中国山区耕地零租金流转现象及其解释

耕地零租金流转已经成为山区普遍存在的现象。零租金流转制约了耕地流转市场健康发展,造成了耕地资源错配,威胁了国家粮食安全。本文在阐释耕地零租金流转的概念和形成机制的基础上,利用2020—2021年实地调查的572个山区村庄样本推算村庄层面耕地零租金流转规模,并采用Heckman模型剖析耕地零租金流转区域差异的影响因素。研究发现:①全国整体上,有79.55%的山区村庄发生耕地流转,平均耕地流转率为15.14%;发生耕地流转的村庄中58.68%的村庄存在零租金流转现象,零租金流转面积比例为22.21%。②区域分布上,中国山区耕地零租金流转现象区域差异明显,西北黄土高原区最为普遍,尤其是甘肃和山西。③耕地资源禀赋对耕地零租金流转区域差异有显著影响,且在东南山地丘陵区和近郊村的影响更显著;劳动力因素整体上对耕地零租金流转区域差异影响不明显,但农业劳动力在西部地区和坡地相对少的村庄影响显著;耕地流转市场特征对耕地零租金流转区域差异有显著影响,且对东南山地丘陵区和极多坡村以及近远郊村有显著影响。为提升地租水平,充分利用山区耕地资源,中国未来应加强改善农业生产条件,积极增加农产品附加值,以及整合新生产要素来提升耕地产出能力;构建统一规范的农村产权交易平台,有效发挥基层村集体中介服务等作用,提升土地流转市场效率。

Temporal and regional variations of China＇s fertilizer consumption by crops during 1998-2008

The agricultural and land policies in China are always focused on protecting its food supply and security because of the country＇s large population and improved diets. The crop production guide ＇Take Grain as the Key Link prompted peasants to plant grain on most of the agricultural land, leading to the majority of fertilizer being used in grain crops for many years in China. This situation has changed dramatically in recent years. Based on data pertaining to provincial crops sown area and fertilizer use per unit area in 1998 and 2008, the temporal and spatial variations of China＇s fertilizer consumption by crops were analyzed at the provincial level, and the results are presented here. （1） Fertilizer consumption in China grew strongly in the last decade, while the growth was mainly attributable to the increase of fertilizer consumption by horticultural crops. The fertilizer consumption of grain crops dropped from 71.0% in 1998 to 57.8% in 2008. Thus, it is concluded that the emphasis of fertilizer consumption is shifting toward horticultural crops. （2） There were marked differences in the growth rates of fertilizer consumption from the regional point of view. The national average growth rate of fertilizer consumption was 31.9% during 1998-2008. The western and northeastern parts of the country came close to the national average, while the eastern part was lower, with an average of 13.0%, and central China was much higher （50.8%）. The increase of fertilizer consumption in central and west China was higher than the other zones, which already accounted for 77.9% of the national total. Thus, it is concluded that the consumption emphasis of chemical fertilizer shifts toward the central and western regions. （3） The decline of fertilizer consumption by grain crops was largely due to the decrease in sown area compared with the increase by vegetable crops attributable to the enlarging sown area; the increase by orchard crops was affected by both expanding the sown area and fertilizer use per unit area.

Paddy rice multiple cropping index changes in Southern China: Impacts on national grain production capacity and policy implications

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.

Impact of the shrinking winter wheat sown area on agricultural water consumption in the Hebei Plain

This study firstly analyzed the shrinkage of winter wheat and the changes of crop- ping systems in the Hebei Plain from 1998 to 2010 based on the agricultural statistic data of 11 cities and meteorological data, including daily temperature, precipitation, water vapor, wind speed and minimum relative humidity data from 22 meteorological stations, and then calcu- lated the water deficit and irrigation water resources required by different cropping systems, as well as the irrigation water resources conserved as a result of cropping system changes, using crop coefficient method and every ten-day effective precipitation estimation method. The results are as follows. 1） The sown areas of winter wheat in the 11 cities in the Hebei Plain all shrunk during the study period. The shrinkage rate was 16.07% and the total shrinkage area amounted to 49.62×10^4 ha. The shrinkage was most serious in the Bei- jing-Tianjin-Tangshan metropolitan agglomerate, with a shrinkage rate of 47.23%. 2） The precipitation fill rate of winter wheat was only 20%-30%, while those of spring maize and summer maize both exceeded 50%. The irrigation water resources demanded by the winter wheat-summer maize double cropping system ranged from 400 mm to 530 mm, while those demanded by the spring maize single cropping system ranged only from 160 mm to 210 ram. 3） The water resources conserved as a result of the winter wheat sown area shrinkage during the study period were about 15.96×10^8 m^3/a, accounting for 27.85% of those provided for Beijing, Tianjin and Hebei by the first phase of the Mid-Route of the South-to-North Water Diversion Project.

How farmers’non-agricultural employment affects rural land circulation in China?

To clarify the impact of non-agricultural employment on rural land circulation in China,we built logit models using the Chinese Household Income Project 2013 dataset,which includes 18,948 household samples over 15 provinces,126 cities and 234 counties of China in 2013.We use the proportion of non-agricultural income,the proportion of non-agricultural laborers and non-agricultural fixed operating assets to reflect the degree of the households’dependence on agriculture,the degree of the households’laborers committed to non-agricultural employment and the stability of non-agricultural employment,respectively.The results show that the stability of non-agricultural employment is an important reason for farmers to transfer out their land,and an increase in non-agricultural income is the fundamental reason.The proportion of non-agricultural assets has the greatest impact on the decision to transfer land,followed by the proportion of non-agricultural income.Per unit increase in the non-agricultural income ratio has a stronger effect on the transfer-out decision than it does on the transfer-in decision,which is a 0.09 increase of the probability of transfer-out the land and a 0.07 decrease of the probability of transfer-in the land.In terms of regional differences,when considering the impact of non-agricultural employment on the land transfer-out decision,the impacts of non-agricultural income and labor force are the greatest in the Central region.The impact of non-agricultural assets is the greatest in the Eastern region.For the Eastern region,the decision to transfer out land is mainly affected by non-agricultural assets and the non-agricultural labor force,and the decision to transfer in land is mainly affected by non-agricultural assets.In the Central and Western regions,the decision to transfer out land is mainly affected by non-agricultural assets,non-agricultural income and the non-agricultural labor force,in that order.The decision to transfer in land in the Central region is not significantly affected by non-agricultural employment.The decision to transfer in land in the Western region is mainly affected by non-agricultural assets,non-agricultural labor force and non-agricultural income,in that order.We note that non-agricultural assets have a prominent impact on land transfer,which shows that the stability of non-agricultural employment has an important impact on land transfer decision-making.Vocational training for rural labor forces may be an effective means to promote stable non-agricultural employment and simultaneously facilitate rural land circulation,especially in Central and Western China.

Spatiotemporal changes in Chinese land circulation between 2003 and 2013

Land circulation is an important measure that can be utilized to enable agricultural management at a moderate scale.It is therefore imperative to explore spatiotemporal changes in land circulation and the factors that drive these variations in order to maintain and increase the vitality of the land rental market.An initial analysis of spatiotemporal patterns in land circulation is presented in this study on the basis of data from 169,511 farm households between 2003 and 2013.The rural fixed observation point system advocated by the Chinese Ministry of Agriculture was utilized for this analysis,and Heckman two-stage models were developed and estimated in order to identify the drivers of regional differences in land circulation at the national scale and at the levels of different terrains.The results of this study show that the rate of land circulation in China rose from 15.09%to 25.1%over the course of the study period,an average rate of 0.8%.More specifically,data show that the rate of land circulation in the south of China has been higher than in the north,that the average land rental payment was 4256.13 yuan per ha,and that 55.05%of households did not pay such a fee during the land circulation process.In contrast,the average rent obtained was 3648.45 yuan per ha nationally even though 52.63%of households did not obtain any payments from their tenants.The results show that land quality,geographic location,transaction costs,and household characteristics have significantly affected land circulation in different regions of China.Specifically,the marginal effects of land quality and geographic location were larger in the plain regions,while transaction cost was the key factor influencing land circulation in the hilly and mountainous regions.The signal identified in this study,rent-free land circulation,is indicative of a mismatch that has led to the marginalization of mountainous regions and higher transaction costs that have reduced the potential value of land resources.Thus,as the opportunity cost of farming continues to rise across China,the depreciation of land assets will become irreversible and the phenomenon of land abandonment will become increasingly prevalent in hilly and mountainous regions in the future.The transaction costs associated with the land rental market should be reduced to mitigate these effects by establishing land circulation intermediaries at the township level,and the critical issues of land abandonment and poverty reduction in hilly and mountainous regions should arouse more attention.