本书是研究劳动力价格上涨对粮食生产的相关影响，涉及劳动力价格上涨后诱导的农业劳动力转移、农业机械化的兴起，以及其对粮食生产效率、种植结构和土地流转等方面的影响。在研究过程中，笔者得到诸多师长的指导并与他们一起合作撰写，在此衷心致谢，他们分别是北京大学张晓波教授、浙江大学黄祖辉教授和阮建青副教授、国际食物政策研究所陈志钢教授、密歇根州立大学金松青教授和托马斯·里尔登（Thomas Reardon）教授、南京农业大学钟甫宁教授等，同时感谢卢小生等编辑为本书的出版付出的大量心血。本书分成以下六个章节：第一章劳动力价格上涨对农业机械的影响。通过研究发现，劳动力价格上涨最先触动的是年轻劳动力，相比较于年纪较大的劳动力而言，随着劳动力价格的不断上涨，年轻劳动力更倾向于进入城市，从事非农工作。从需求层面来看，农村内部由于大量劳动力的转移，剩余的劳动力已经变得稀缺，再也无法维持传统的“互帮互助”式的农业生产模式，富有竞争性的农村劳动力市场逐渐形成。但是，由于近些年来劳动力工资上涨太快，农户家庭通过雇用农村市场中的劳动力从事农业生产会大幅度提升生产成本，使生产粮食变得不划算，因此“雇工式”的农业生产方式并不适应当前的中国农村形势。另外，单个农户家庭自己购买农业机械也不划算，因为单个农户的土地规模太小，单位土地的农业机械成本太大，这种农业生产模式也不可能。近年来，农村地区涌现的农业机械跨区作业的社会服务方式，是单个农户家庭的最优选择。从供给层面来看，中国地区之间的气候差异，使得中国地区之间的粮食收割在时间上形成了一个较长的梯度，个体农户可以通过购买大型农业机械在全国十几个省份内进行收割作业，跨区作业时间一年长达7个月，这样就充分降低了个体农户购买农业机械进行跨区作业的单位土地机械成本，使得他们可以盈利，从而在供给层面保障了农业机械社会服务的形成。在厘清了劳动力价格诱导农业机械替代农业劳动力机制以后，采用微观农户数据实证分析了劳动力价格对使用农业机械的影响。研究结果表明，在控制了其他影响因素的前提下，劳动力外出打工工资对农户家庭使用农业机械有显著正向影响，其劳动力外出打工工资每增加1倍，则农户家庭在每亩农业机械上的花费会增加44.3%。另外，实证结果表明，劳动力外出打工工资对平原地区的正向影响更加显著，劳动力外出打工工资每增加一倍，平原地区农户家庭每亩农业机械花费会增加55.8%，而山岭地区每亩农业机械花费只增加17.3%。第二章农业机械替代劳动力对粮食生产效率的影响。农业机械的使用是否会对粮食生产的生产率产生影响？因为传统的农业经济学总是认为精耕细作会增加生产率，而粗放式经营则会损失生产率。为了验证这个问题，笔者利用多个微观农户调查数据库进行实证研究，采用得分匹配的实证估计方法，研究结果表明，农户家庭使用农业机械跨区作业服务并不对粮食生产产生负面影响。第三章劳动力价格、人口结构变化对粮食种植结构的影响。本章分别从宏观省级层面和微观农户家庭层面进行实证研究。研究结果表明，在宏观省级层面，农村劳动力价格上涨对粮食作物的种植比例有显著负向影响，而对经济作物的种植比例有显著正向影响，尤其是对蔬菜作物种植比例促进幅度较大。微观农户层面的实证结果与宏观结果保持一致，凸显了实证结果的稳健性。在农户家庭人口结构方面，宏观层面和微观层面的实证结果都表明老年劳动力比例对粮食生产无显著影响，而女性劳动力比例高对粮食种植比例有显著负面影响，而对经济作物种植比例有正面影响。第四章劳动力价格、人口结构变化对农村土地流转的影响。本章主要利用微观农户数据进行实证研究。研究结果表明，劳动力价格上涨在平原地区对农村土地租入和租出都有显著正向影响，即劳动力价格上涨会促进平原地区农村土地租赁市场的发育。而山岭地区实证结果表明，劳动力价格上涨对农村土地租赁没有显著影响。在人口结构层面，无论是分土地租入或者租出，还是分总样本、平原地区和山岭地区进行分析，实证结果均表明，农户家庭人口的老龄化和女性化对农村土地租赁市场并不构成显著影响。人口结构的老龄化和女性化是否会加剧或者减弱劳动力价格上涨对农村土地租赁市场的影响，实证结果也表明，在统计学上不存在显著影响。第五章劳动力外出打工和本地非农就业对粮食生产效率的影响。本章研究了农户家庭外出打工和本地非农就业行为对粮食生产效率的影响。将关联随机效用分析方法引入随机前沿生产效率估计模型，控制了某些无法观察到的内生性影响因素之后，实证结果表明，本地非农就业和外出打工对粮食生产效率都没有显著负向影响，打破了认为农村劳动力转移必然给农业生产效率带来负面影响的观点。第六章总结和展望。随着经济的发展，劳动力价格也会不断攀升，农户可能更倾向于在未来种植收益高的经济作物。按照市场经济的发展，小规模和细碎化的粮食生产方式可能会逐渐减少。应对这种变化，未来国家的可能路径在于粮食生产的集中化、集团化生产，建立更多类似新疆地区的大型粮食农垦集团进行集中生产。集中生产，可以突破大型农业机械较难应用于细碎化农田的限制，降低每亩的机械使用成本。大型农业机械的广泛使用，也可以为工业和服务业节省出更多的劳动力。在土地方面，虽然劳动力价格上涨能够有效诱导土地加速流转，但是，毕竟规模和数量有限，政府可能需要采取更多方式来鼓励土地流转，比如土地入股等，让土地集中起来，打破传统细碎化的经营方式，去除田埂，使土地集中成片进行机械化生产。

This book studies the impact of rising labor prices on food production, including the transfer of agricultural labor and the rise of agricultural mechanization induced by rising labor prices, as well as their impact on food production efficiency, planting structure and land circulation. In the process of research, the author received guidance and co-authored with many teachers, including Professor Zhang Xiaobo of Peking University, Professor Huang Zuhui and Associate Professor Ruan Jianqing of Zhejiang University, Professor Chen Zhigang of the International Food Policy Research Institute, Professor Jin Songqing and Professor Thomas Reardon of Michigan State University, Professor Zhong Funing of Nanjing Agricultural University, and thank editors such as Lu Xiaosheng for their great efforts in the publication of this book. The book is divided into the following six chapters: Chapter 1: The Impact of Rising Labor Prices on Agricultural Machinery. The study found that the first thing that touched the rising labor price was the young labor force, and compared with the older labor force, with the rising labor price, the young labor force was more inclined to enter the city and engage in non-agricultural work. From the perspective of demand, due to the transfer of a large number of labor in rural areas, the remaining labor force has become scarce, and the traditional "mutual help" agricultural production model can no longer be maintained, and a competitive rural labor market has gradually formed. However, because labor wages have risen so rapidly in recent years, peasant households will greatly increase the cost of production by hiring labor in the rural market to engage in agricultural production, making it uneconomical to produce food, so the "hired labor" agricultural production method is not suitable for the current situation in rural China. In addition, it is not cost-effective for a single farmer family to buy agricultural machinery by itself, because the land scale of a single farmer is too small, the cost of agricultural machinery per unit of land is too large, and this agricultural production model is also impossible. In recent years, the social service mode of cross-regional operation of agricultural machinery emerging in rural areas is the best choice for individual farming households. From the supply level, the climate difference between China's regions makes the grain harvesting between Chinese regions form a long gradient in time, individual farmers can purchase large-scale agricultural machinery in more than a dozen provinces in the country to carry out harvesting operations, cross-regional operation time up to 7 months a year, which fully reduces the unit land machinery cost of individual farmers to purchase agricultural machinery for cross-regional operations, so that they can make profits, thereby ensuring the formation of agricultural machinery social services at the supply level. After clarifying the mechanism of labor price induced agricultural machinery to replace agricultural labor, the influence of labor price on the use of agricultural machinery was empirically analyzed by using micro-farmer data. The results show that under the premise of controlling for other influencing factors, the wages of migrant workers have a significant positive impact on the use of agricultural machinery by rural households, and for every time the wages of migrant workers go out to work, the expenditure of rural households on agricultural machinery per mu will increase by 44.3%. In addition, empirical results show that the positive impact of labor wages on plain areas is more significant, and for every doubling of labor wages going out to work, the cost of agricultural machinery per mu of rural households in plain areas will increase by 55.8%, while the cost of agricultural machinery per mu in mountainous areas will only increase by 17.3%. Chapter 2: The Impact of Agricultural Machinery Replacement Labor on Food Production Efficiency. Will the use of agricultural machinery have an impact on the productivity of food production? Because traditional agricultural economics always believes that intensive farming will increase productivity, while extensive management will lose productivity. In order to verify this problem, the author used multiple micro-farm household survey databases to conduct empirical research, and adopted the empirical estimation method of score matching, and the results showed that the use of agricultural machinery cross-regional operation services by farmers did not have a negative impact on food production. Chapter Three: The Impact of Labor Prices and Demographic Changes on the Structure of Grain Planting. This chapter conducts empirical research from the macro provincial level and the micro farm household level, respectively. The results show that at the macro provincial level, the rise in rural labor prices has a significant negative impact on the planting ratio of food crops, while it has a significant positive impact on the planting ratio of cash crops, especially on the proportion of vegetable crops. The empirical results at the micro farmer level are consistent with the macro results, highlighting the robustness of the empirical results. In terms of the demographic structure of rural households, both the macro and micro empirical results show that the proportion of elderly labor has no significant impact on food production, while the high proportion of female labor has a significant negative impact on the proportion of food planting, but has a positive impact on the proportion of cash crops. Chapter IV: The Impact of Labor Prices and Demographic Changes on Rural Land Circulation. This chapter mainly uses micro-farm data for empirical research. The results show that the rise in labor prices has a significant positive impact on rural land rental and lease in plain areas, that is, rising labor prices will promote the development of rural land leasing market in plain areas. The empirical results show that the rise in labor prices has no significant impact on rural land leasing. At the level of demographic structure, whether it is by land lease or lease, or by total sample, plain area and mountain area, the empirical results show that the aging and feminization of rural household population do not have a significant impact on the rural land leasing market. The empirical results also show that there is no statistically significant effect on whether the aging and feminization of the population structure will exacerbate or weaken the impact of rising labor prices on the rural land rental market. Chapter 5: The Impact of Migrant Labor and Local Non-farm Employment on Food Production Efficiency. This chapter examines the impact of migrant work and local non-farm employment on food productivity. After introducing the associative stochastic utility analysis method into the stochastic frontier production efficiency estimation model and controlling for some unobservable endogenous influencing factors, the empirical results show that local non-farm employment and migrant work have no significant negative impact on food production efficiency, breaking the view that rural labor transfer will inevitably have a negative impact on agricultural production efficiency. Chapter VI Summary and Outlook. As the economy grows, labor prices will continue to rise, and farmers may be more inclined to grow high-yield cash crops in the future. According to the development of the market economy, small-scale and finely fragmented food production methods may gradually decrease. In response to this change, the possible path for the country in the future lies in the centralization and collectivization of grain production, and the establishment of more large-scale grain farming groups similar to Xinjiang for centralized production. Centralized production can break through the limitation that large-scale agricultural machinery is difficult to apply to fine crushed farmland, and reduce the cost of machinery per mu. The widespread use of large agricultural machinery can also save more labor for industry and services. In terms of land, although the rise in labor prices can effectively induce the accelerated circulation of land, after all, the scale and quantity are limited, and the government may need to adopt more ways to encourage land circulation, such as land shareholding, etc., so that land can be concentrated, break the traditional and fragmented management methods, remove field ridges, and concentrate land into pieces for mechanized production.（AI翻译）