【作者】 梁红梅；

【导师】 刘卫东；

【作者基本信息】 浙江大学 ， 土地资源管理， 2011， 博士

【摘要】 耕地保护是我国的一项基本国策,但运行效果并不十分理想,其中一个重要原因就是在全国范围内平均用力,实行“一刀切”模式。本文提出并论证了种植业优势区域是耕地保护的重点区域这一基本观点和策略,并采用信息量法在县级尺度上测度了7种主要农作物区域优势,以信息量为基础识别和划分了相应的优势区域,探讨了它们的形成、演化规律及其与种植业布局变化的关系,最后选择并确定了种植业7个主要优势区域,作为耕地的重点保护区域,并以这一基本策略为依据,结合灰色关联分析提出了相应的耕地保护措施。这一研究以种植业区域优势测度和优势区域的识别、划分与选择为重点,试图回答我国究竟哪里应该保护耕地?为什么那里要保护耕地?那里应该怎样保护耕地等基本问题,从一个方面丰富了耕地保护的研究内容,为耕地保护政策有效实施和种植业优势区建设提供了客观依据,对种植业结构调整和合理布局也具有一定指导作用。主要结论如下：(1)根据信息量法模型与要求,构建了“本源+表象”综合指标体系、解决了指标分级、样本单元选择、信息量计算与分析、变量与信息量组合等技术问题,测度了7种主要农作物的区域优势。这一方法克服了多变量分析中权重赋值的主观性,同时还考虑了指标值级的影响,计算简便,结果可信。(2)种植业区域优势根据总信息量大小可划分为优势、弱势与劣势3类,评价单元可相应归为优势单元、弱势单元和劣势单元。以区域优势为基础,遵循一定的原则,识别和划分出7种主要农作物的优势区域。水稻有长江中下游、东南沿海和四川盆地3个优势区。小麦有黄淮海、长江中下游和四川盆地3个优势区。玉米有东北、北方、西南和新疆4个优势区。大豆有东北、北方和西南3个优势区。薯类有东北、北方和西南3个优势区。棉花有西北、黄淮海和长江中下游3个优势区。油料有华北、长江中下游、四川盆地和东南沿海4个优势区。长江中下游、黄淮海和东北地区还是我国最重要的种植业双重优势区。同时,长江中下游还是最显著的种植业三重优势区。(3)根据众数变量和信息量组合的时空变化规律,识别出影响7种主要农作物各优势区形成的主导因素、积极因素和限制因素。在所有优势区中,播种面积、单产、有效灌溉率、农业供水能力、土地生产潜力和劳均耕地面积出现频率最高,在种植业优势区域的形成过程中起主导作用。平均信息量的变化反映了各优势区近20年的演化过程与发展轨迹。尽管生产状况有所不同,但7种主要农作物各优势区的区域优势总体均趋于增强,优势单元数量增加,空间分布更加集中,且优势区地理位置向北移动。(4)生产布局现状图和差值图显示,我国种植业在空间上向北迁移,北方已成为种植业生产重心。优势区是稳定的生产中心,诱导或吸引种植业生产作“向心”运动,一方面使自身区域优势更加突出,另一方面还决定了生产布局变化的方向和幅度。种植业生产布局变化也会导致新的优势区出现,并力图不断强化,有时也会出现少量背离区域优势现象。(5)我国有7个种植业主要优势区域(东北区、北方区、黄淮海区、西北区、长江中下游区、西南区和东南区)。它们是耕地保护的重点区域,涉及1624个县级行政区域,国土面积约570x 104km2。1997～2007年间,其耕地面积从9296.04x 104hm2降至8401.51×104hm2,减幅高达894.53×104hm2,变化率为-9.62%。灰色关联分析揭示了种植业主要优势区域耕地变化的主导因素和基本原因,折射出耕地保护的突出问题。种植业主要优势区域耕地保护的基本策略与措施是：①探索和建立耕地保护区域补偿机制；②产业结构调整应保护种植业区域优势；③特别重视水土资源的充分供给和高效利用；④全面提高农业现代化水平。更多还原

【Abstract】 Arable land protection as a national policy of china, hasn’t gained satisfied result for the past decades years, one of the most important reasons is that performance force was shared with all over the country. Thus, it has been emphasized as a basic academic viewpoint and tactic that arable land protection should be strongly carried out in advantage regions of crop farming (ARCF). Information Content Method (ICM) was applied to estimate regional advantage degree of crop farming on the county scale level, which is reflected by the total information content (TIC) of each evaluated unit. The advantage regions of seven main crops were distinguished and divided from the TIC, and their formation and evolvement were studied in terms of TIC change. Furthermore, the close relationship between these regions and crop farming distributions was discussed in detail. All above researches attempt to answer some public concerned questions such as why, where and how arable land should be protected, and provide governments with some consultations about advantage regions development, structural adjustment and rational distribution of crop farming. Some major conclusions are as follows:Firstly, ICM can be used to assess regional advantage degree of crop farming after some key techniques are resolved, for example, index system, variable grade, sample choice, TIC calculation, variables and their information contents assemblage.Secondly, the assessment units are correspondingly classified into three types, that is, advantage units, weak units and disadvantage units according to regional advantage degree of crop farming. There are three rice advantage regions, which are Middle and Lower Reaches of Yangtze River (MLRYR), Southeast Coastal of China (SECC) and Sichuan Basin (SCB). Three wheat advantage regions exist in Huanghuaihai (HHH), MLRYR and SCB. Four corn advantage regions located in Northeast China (NEC), Great Wall Zone (GWZ), Southwest China (SWC) and Xinjiang. NEC, GWZ and SWC advantage regions belong to soy bean crop, potato and yam crop, but their realm and geographic locations are not completely overlapped. Three cotton advantage regions lie in Northwest China (NWC), HHH and MLRYR. There are four oil crop advantage regions named Northern China (NC), MLRYR. SCB and SECC.Thirdly, the leading, active and restrict factors affecting formation of ARCF are distinguished from majority variables and their information contents assemblage. Frequently, the leading factors are sow area, yield per unit, valid irrigation rate, water supply ability of agriculture, land potential. It is illustrated by the mean information contents that the advantage degrees are strengthen and the amount of advantage units is increasing in ARCF.The fourth, ARCF result in agglomeration of crop farming and northern part of China has become the center of crop production. On the other hand, distribution changes of crop farming also promote occurrence of new ARCF.Finally, there are seven key regions of arable land protection, which are also major ARCF and named respectively Northeast Region, Great Wall Region, Huanghuaihai Region, Northwest Region, Middle and Lower Reaches of Yangtze River, Southwest Region and Southeast Region. For the last decade years, arable land has decreased 8.9453 million acres and change rate has reached-9.62 percent in the above seven major ARCF. Some arable land protection tactics and measures are drawn up according to Grey Relevance Analysis. The most important suggestions include exploring regional economic compensation mechanism, maintaining the advantage of ARCF in adjusting industrial structure, fully supplying and efficiently using water and land resources and promoting agro-modernization.更多还原