【作者】 彭长青；

【导师】 卞新民；

【作者基本信息】 南京农业大学 ， 作物栽培学与耕作学， 2007， 博士

【摘要】 在我们这样一个正处于发展中的人口大国,稳定和提高粮食生产历来是国家有关方针政策的重要内容。江苏省作为我国东部沿海典型的经济发达省份,在经济高速发展的同时,面临着耕地非农占用普遍、粮食生产严重削弱的难题,“人粮矛盾”日益突出。以区域经济非均衡协调发展作为基本出发点的江苏沿江开发战略,旨在新型工业化进程中,更为高效的承接国际制造业基地转移,促进沪宁沿线高新技术产业提升,进一步带动苏北地区加快发展,使沿江地区成为江苏经济社会发展新的增长极。但是,工业制造业的发展、城市化进程的加快势必对沿江地区原本已经较为稀缺的土地资源产生更大的需求,同时非农就业机会的增多、消费结构的变化也将对粮食生产、农业生产产生更深入的影响,最终影响到区域粮食供需态势。区域粮食供需平衡是确保国家粮食安全的重要前提。鉴于此,本研究在搜集整理大量统计资料和综合分析2000家制造业企业实地调查数据的基础上,以沿江开发中沿江地区经济增长和产业结构变化为突破口,构建了基于经济增长和产业发展的人口数量变化模型、新增土地占用模型、人均粮食消费模型,并通过不同增长速度和产业发展模式的沿江开发情景设定,结合上述模型,对2010、2020年沿江地区粮食产需平衡系统进行了预测和分析。最后提出了确保沿江地区粮食供需平衡的对策建议。主要研究结果如下:(1)沿江地区产业结构历史演变与发展趋势沿江各市产业结构演变存在一定的规律性,各市第一产业的比重逐年下降,经济非农化水平逐步提高;第二产业比重处于接近60%的较高水平,对区域经济发展的影响较大;第三产业逐步取代第一产业的份额,产出比重稳步提高。结合发达国家和地区的发展经验、专家学者的研究论断、沿江地区产业结构的历史演变轨迹和沿江开发的产业发展战略,沿江地区第二产业比重还将在60%左右徘徊一段时期。(2)沿江地区粮食消费子系统从沿江地区人口变化态势来看,沿江地区户籍人口总量稳步增加;城镇化水平逐渐加快,2010、2020年可能分别达到65%和70%;计量经济分析表明,外来人口聚集程度与区域经济发展程度呈现出极显著的正相关关系,人均GDP越高的地方,外来人口比重越高。不同行业的劳动生产率不同,以沿江地区为例,建立了基于产业发展视角的人口数量变化模拟模型。关于人均粮食消费,城镇居民人均粮食总消费量和人均口粮消费量、农村居民人均口粮消费量逐年递减,且与经济发展水平(人均GDP)有着很好的乘幂函数关系,而农村居民人均粮食总消费量虽有波动,但变化不大;根据实地调查结果分析发现,沿江地区外来人口人均口粮消费量的平均值为234.51kg,略高于农村居民人均口粮消费量,而人均粮食总消费量的平均值为385.97kg,同样高于农村居民人均粮食总消费量。由此可见,农村劳动力在转移后,其粮食消费量有所增加。(3)沿江地区粮食生产子系统在粮食生产方面,受农业结构调整和耕地面积减少的影响,沿江地区粮食产量有所下降,粮食总产量占全省的比重逐年降低,由1980年的58.44%降到了2005年的42.86%。人均粮食仅略高于300kg。耕地面积逐渐减少、粮食播种面积大幅下降、粮食单产增加乏力、周边区域粮食供需态势不容乐观等四大因素使沿江地区粮食供需形势严峻。耕地快速非农化是粮食生产的重要制约因素,而沿江地区耕地非农化主要受以制造业为主体的建设用地需求的驱动。以耕地面积变化为着眼点,从非农产业用地效率的角度,结合2000家制造业企业的实地调查数据,探讨了不同制造业行业的用地经济效率特征,对所研究的28个制造业行业土地利用效率进行了聚类分析,建立了基于产业发展视角的耕地非农化模拟模型。(4)沿江开发情景设定与粮食产需系统模拟采用情景设定方法,从经济增长速度、产业发展模式等方面,进行了沿江开发情景设定,并结合前文所建立的模拟模型,对沿江开发新形势下的沿江地区2010、2020年粮食产需状况进行了综合模拟。结果表明:经济增长速度越快,产业发展所需的劳动力数量越高,对外来人口的需求也越大,同时,更增加了耕地非农占用;不同产业发展模式下,对维持沿江地区经济发展所需的人口和劳动力数量、建设用地需求也存在一定的差异。总的来看,2010、2020年沿江地区粮食产需平衡态势不容乐观。①到2010年,如果考虑外来人口粮食消费,且经济增长速度控制在18%以内,沿江地区能够实现口粮基本平衡,但即便经济增长速度仅9%,其粮食总量平衡也较难实现;如果不考虑外来人口粮食消费,沿江地区粮食总量平衡问题不大。②到2020年,如果考虑外来人口粮食消费,在经济增长速度高于15%的情况下,口粮基本平衡难以保障;如果不考虑外来人口粮食消费,且经济增长速度控制在15%以内,可以实现粮食总量平衡。③沿江地区今后的粮食供需平衡政策目标应放在“立足于区域人口总量的口粮产需基本平衡”。实现这一目标,对于沿江和江苏粮食安全具有积极而重要的意义。(5)沿江地区粮食供需平衡的对策措施①基于GIS技术、空间自相关分析和遗传算法的沿江地区粮食生产空间布局优化研究表明,空间布局优化后,沿江地区粮食总产量和种植业效益可提高7%左右。深入研究沿江地区粮食生产空间布局优化方法,并付诸实践,有利于沿江地区粮食增产、农业增效、农民增收。②水稻生产是沿江地区粮食生产的重中之重,提高水稻单产是保证沿江地区口粮供需平衡的有效措施。田间试验结果表明,水稻机械化插秧省力、省工、节本,是沿江地区未来水稻生产的发展方向。其高产栽培关键技术的适宜值应为:芽谷播量每盘(1624 cm~2)150-180g,秧田培肥采用壮秧剂,移栽密度为小棵密植(取秧面积1.26 cm~2、株距11.7 cm、行距30 cm);基蘖肥:穗肥=6:4。③沿江地区粮食供需平衡的政策建议:一要保护和合理利用耕地;二要科学引导人口流动,促进科学消费与节约消费;三要加快完善粮食流通体系建设;四要注重农业科技创新与农技推广体系建设;五要加大水稻机械化种植配套农艺技术研究与推广。更多还原

【Abstract】 China is a big developing country with a large population.Stabilizing and increasing grain production is an important national policy.As a typical developed province in the east part of China,Jiangsu has to face the problems that more and more farmland is used for non-farm purpose and the grain yield is decreasing,and the conflict between people and land is more and more intense,while it is developing fast. To make this area be a new increase polar in Jiangsu,it takes unbalance development of regional economy as its basic springboard,so that the riverside area can carry out the transfer of the manufacturing base which has higher effect.That can also accelerate the exaltation of the high and new technology industry along the Hu-Ning line,which will drive the development of the north Jiangsu too.But this stratagem may finally effect the situation of the area grain production and requirement.Because the development of the manufacturing industry and the accelerating of the progress of urbanization would need much land which lacks of,and the increase of work chance in the non-farm people,the change of the consumption frame would affect the dominance of the production of the grain and farming more deeply.The balance of the regional grain supply and requirement is an important precondition for national food safety.For this reason,we collected and coordinated a large number of statistical data,fieldwork and surveys of more than 2000 corporations to study this issue.Based on the analysis of the relationship between development of the area economy and the industrial structure,we built a series of models including change of population,newly added use of land,grain consumptions per capita.And then,according to these models,we set different development scenes to forecast and analyze the supply-demand system of riverside area in 2010 and 2020.The central research results were as follows:(1) The historical evolution and development trends of industrial structure in the Yangtze riverside area of Jiangsu ProvinceThere was certain regularity in the evolution of the industrial structure among the riverside cities.Firstly,the proportion of primary industry decreased year by year, while the level of non-agriculturalization economy improved gradually;secondly, with the 60 percent level,the secondary industry proportion made great influence on the regional economic development;thirdly,the output proportion improved steadily, with the tertiary industry gradually replacing of primary industry.Combining with the experiences in the developed countries and regions,the conclusion made by experts and scholars,the regional historical evolution of industrial structure and the regional industrial development strategy,we concluded that the proportion of the secondary industry would hover around the level of 60%for a period of time.(2) The grain consumption subsystemFrom the situation of regional population change we could see that the household registration population increased steadily,and the level of urbanization accelerated gradually as well,which would respectively reach 65%and 70%in 2010 and 2020. The econometric analysis showed that the per capita GDP had significant positive correlation with the proportion of external population in this area.The labor productivity was different in various sectors.Taking the riverside area of Jiangsu Province for example,we established a simulation model of population changes from the view of industry development.As for the per capita grain consumption,the urban residents per capita total grain consumption,in the one hand,the per capita grain consumption and the rural residents per capita gain consumption gradually declined,which experienced exponentiation function relationship with the economic development level(GDP per capita).On the other hand,the rural residents per capita total grain consumption fluctuated,but the change was not significant.Survey results showed that the average number of per capita consumption of the external population was 234.51 kg in the riverside area,a little higher than that of rural residents,while the per capita total grain consumption averaged 385.97 kg, higher than that of rural residents per capita.Evidently,when the rural labors transferred,their grain consumption increased as well.(3)The grain production subsystemDue to the impact of agricultural structure adjustment and farmland area shrank, the grain production of the riverside area had decreased,while the total grain yield of the Yangtze delta accouted for the whole province decreased from 58.44%in 1980 to 42.86%in 2005.The per capital grain was slightly higher than 300kg.It is lessening farmland,decreasing planting area,low grain output raise rate and pessimistic supply and demand state in area nearby,which made the supply and demand state grim.Cultivated land conversion was the main factor that influenced the grain production in the Yangtze riverside area of Jiangsu Province,which was effected by the demand of construction land based on manufacturing in Jiangsu.Focused on the transformation of the farmland area,combined with the data of investment,and also studied the character of the economical efficiency of different manufacturing industry, we analyzed the using efficiency of land,occupied by the 28 manufacturing industry; and then classified the land economical production into six categories:very high, higher,moderate,middle-lower,lower and very low.Basing on the industry-land demands hypothesis we established the farmland non-agricultualization simulating model.(4)The exploitation situational setting and grain production-demand systematic simulation in the Yangtze riverside area of Jiangsu ProvinceStarting from the speed of economic growth,and the industry development model,using the situational setting method to set the development situational in the Yangtze riverside area of Jiangsu Province,and combining with the former established stimulation model,we simulated the grain production-demand system of the along-river exploitation in the new situation in 2010 and 2020.The results indicated that the quicker the economic growth speed increased the more labor force the industry development was demanded and the more external population was demanded.At the same time,the farmland non-agriculture occupying was increased. The demand quantity of population and labor force and land use were different which for maintaining the along-river region economic development in different industrial development models.In all,the grain production-demand balance situation was not optimistic.①By 2010,if concerned with the grain consumption of the external population, and controlled the economic growth speed lower than 18%,the grain production-demand would be balance in riverside area.However,even if the economic growth speed was only 9%,the production-demand would not be balance at all.If we didn’t concern with the grain consumption of the external population, ensuring the balance of grain total quantity was not difficult.②By 2020,if concerned with the grain consumption of the external population, the grain production-demand would not be balance if the economic growth speed was higher than 15%;If we didn’t concern with the grain consumption of the external population,and control the growth speed lower than 15%,the balance of grain total quantity would come true.So in the along-river exploitation new situation,the policy goal for grain production-demand balance should be "basing on nearly balance of the grain production-demand for regional total population".The realizing of this goal was quite important for the grain security in along river region and in Jiangsu.(5)The countermeasure suggestions to assuring the grain supply-demand balance in the area along-river in Jiangsu①Based on the GIS technology,spatial autocorrelation analysis and genetic algorithms,the distribution optimization study of grain production areas along the River showed that,after the optimization,the grain output and planting benefits could be a seven-percent increase.Also,we studied the method and practice of space distribution optimization,and then put it to the implementation level.We concluded that could be good for the grain production,peasants’ income and rural development in the riverside area.②Rice production was the most important in grain production.Improving the rice yield was an efficiency measure to ensure the supply and demand balance of rations in the riverside area of Jiangsu Province.The field experiments showed that machine transplanted rice saved labor and cost.The suitable value of Key Cultural Technique showed as:ⅰ) The appropriate sowing rate was 150～180 g per tray(1624 cm~2);ⅱ) Close planting with fewer seedlings in each cluster;ⅲ) Fertilizer for tillering to fertilizer for heading was 6 to 4.③Policy suggestions of the grain supply-demand balance in the riverside area of Jiangsu Province showed as:Firstly,protected and used farmland reasonably; secondly,scientific guided of population movements and promoted scientific and saving consumption;thirdly,speeded up accomplishing construction of cereal circulation system;fourthly,paid attention to agricultural sci-tech innovation and constructed the agricultural technology extension system;fifthly,increased the research and extension of mechanized planting mating technique.更多还原