农业是国民经济的基础,对于国民经济持久、稳定和高速度的发展,起着决定性的作用。为了完成在本世纪内实现四个现代化的任务,国家将从各方面加速农业的发展,集中主要精力,尽快把农业搞上去。在这样的形势下,就更显得研究农业区划的迫切性。

Agriculture as an important and rather a specific department of material produc-tion, is obliged from the very outset of its development to natural geographical basis which is composed of stretches of land geographically zonal and non-zonal, interlocked and compounded with one another. Although agriculture owes its productivity all the time to the concerted and coordinating action of nature, it is by no means a truth that strict control and manipulation by man over the process of its production is unnecessary. Therefore it can hardly be said that the different regional productivity is largely dependant upon its being operated on natural geographical bases of different qualities.Agricultural region is a matter of objective entity. It can not be demarcated arbitrarily. The fundamental tasks of agricultural regional study must be based on the following consideration: a profound knowledge based on a thorough-going research and investigation of the formative process of an agricultural region coupled with a scientific classification of the land; an elaboration of the condition indispensable for the formation; and a scientific analysis of the present features in production with in mind a prospect of the development in the long run and the necessary technical means to effect it.Agricutural regions are individually in such different developing stages as from the lower to the higher. They are subject to constant changes, therefore of a dynamic nature. While some are in a period of steady development with only minor inter-regional changes, others are still in the course of being composed and decomposed indicating that a new region is in the making. All these features could be found in the changes undergoing in the agricultural regions both class I and class II in Jiangsu during the past ten years or more.The six first class agricultural regions set up in Jiangsu in the early 60’s may well be illustrated as fundamentally consistant with the actual geographical conditions, following an observation made in a comparatively long period of time and a recent re-checkup. A number of new changes, however, have been .observed such as the case with Xuzhou-Huaiyin region where a single dry-farming was much preferred in early days, but both dry and paddy farming are equally emphasized now. It has become a region where agricultural production has increased with rice output above all the other crops and surplus commodity food capable of being exported as against the insufficient food supply to its own consumption in early days. Owing to the different characteristics of the natural environment of the region, and in addition, some econo-mical crops likely to be centered in its northern and western parts, the region may well be devided into two first class agricultural regions, at present it is taken as two sub-regions in management, namely the North-Bast patch along Yi-Shu He and the South- West patch along the abondoned Huang He. Another instance is that the Li Xia He agricultural region (in the middle part of Jiangsu) has been developed into a production base for producing commodity grain and cotton. More than 5 million mou of paddy field where rice was grown once a year in the past has now been converted into a field essentially growing both rice and wheat successively in one year, Meanwhile some sections of the border line between this region and regions on the seaside seems to have been pushed a little eastward. Furthermore, agricultural region in Tai Lake area, and Zhenjiang-Yangzhou area, on the seaside and along the Chang Jiang have witnessed changes of different magnitude.It is not unnatural that in different periods of time, the agricultural regions are sure to meet with some different problems of production distribution. The three major problems in the agricultural regions in Jiangsu have in commonare as follows:(I) Problem of cropping system and distribution of crops In Jiangsu cropping system and distribution of crops are centered in an effort to raise the utilization rate of field. The multiple-cropping index for th