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传统上,我国的农业地域划分都是四大农业地区,即南方地区、北方地区、西北干旱半干旱地区、青藏高寒地区。但是,这种划分只能概略地反映我国农业的重大地域差异。在《中国综合农业区划》一书中,则将东部的北方地区分成4个农业区,南方地区分成3个农业区,这样,就将全国陆地部分分成9个一级农业区,现将其存在问题及发展方向分别概述如下。东北区本区包括黑龙江、吉林、辽宁(除朝阳地区外)3省及内蒙古东北部大兴安岭地区。本区农垦历史较晚,人均耕地较多,是全国商品粮、大豆、木材等农林产品的重要生产基地。本区农业自然条件的不足主要是:由于纬度较高,热量资源不够充足,冬季严寒且寒冷期长,作物生长期短,积温不高,大部分地区冬小麦不能越冬,只能一年一熟。北部地区农作物生长期内常出现低温冻害,影响水稻、玉米、高粱、大豆等作物的正常成熟,易于造成大幅度减产,尤以三江平原及松花江中、下游地区低温冷害出现的频率高。
Traditionally, China’s agricultural area is divided into four major agricultural areas, namely, the southern region, the northern region, arid and semi-arid regions of the northwest, alpine regions of Qinghai-Tibet. However, this division can only roughly reflect the major regional differences in agriculture in our country. In the book “China’s Comprehensive Agricultural Zoning”, the northern area of the east is divided into four agricultural areas, and the southern area is divided into three agricultural areas. Thus, the national land area is divided into nine first-level agricultural areas and is now present The problems and development directions are summarized as follows. Northeast China includes Heilongjiang, Jilin, Liaoning (except Chaoyang) and Daxinganling in northeastern Inner Mongolia. The history of farming and land reclamation in this area is relatively late with more per capita arable land. It is an important production base of agricultural and forestry products such as commodity grains, soybeans and timber in China. Due to the high latitude, inadequate heat resources, cold winter and long cold period, short crop growth period and low accumulated temperature, winter wheat in most areas can not win winter and can only be cooked in one year. Low temperature frost damage often occurs in the northern crop growing season, affecting the normal maturity of crops such as rice, corn, sorghum and soybean, which can easily lead to a significant decrease in production. Especially in the middle and lower reaches of the Sanjiang Plain and the Songhua River, low frequency chilling injury occurs frequently.