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一、南疆农垦团场的土壤、气候特点 (1)极其不利的土壤条件 南疆农垦团场处于封闭的内陆盆地,垦前多属各类盐土和棕漠土,原始含盐量高达5—10％,自然植被稀疏,生物积累过程微弱,自然肥力低,虽经多年垦殖,但仍然处于“三高一低”(即地下水位高,地下水矿化度高,土壤含盐量高,土壤肥力低)状况。大部分团场地下水埋深2米左右,矿化度15—150克/升,一米土体含盐1—1.5％,高的3％,少数条田达10—15％。据南京土研所赴南疆调查,阿克苏地区各团场175个耕层标本年均有机质含量为0.86％,处于低水平;含氮量为0.048％,水解氮为37.2PPm,处于低和中下水平;全磷含量虽高为0.14％,但它因多与钙结合成难溶性的磷酸三钙,很难转化成速效磷,有效性仍低。速效磷含量低至6.8PPm,潜在养分和速效养分俱缺。显然“三高一低”是南疆农垦团场发展农业生产的主要障碍因子。
1. Soil and climatic features of the southern farmland reclamation area (1) Extremely unfavorable soil conditions The southern farm reclamation area is in a closed inland basin. Before the reclamation, it belongs to all kinds of saline soil and brown desert soil. The original salt content is as high as 5 -10% natural sparse vegetation biological accumulation of weak natural fertility is low, although after years of cultivation, but still in the “three high and one low” (that is, high groundwater levels, high groundwater salinity, soil salinity, soil Low fertility) condition. Most groups groundwater depth of about 2 meters, salinity of 15-150 g / l, 1-1.5% of one meter soil salt, high 3%, a few fields up to 10-15%. According to a survey conducted by Nanjing Research Institute of Soil Science in southern Xinjiang, the average organic matter content of 175 tillage piles in various fields in Aksu Prefecture was 0.86% at a low level. The nitrogen content was 0.048%, and the hydrolysis nitrogen was 37.2ppm, Level; although the total phosphorus content is 0.14% high, but it is due to the combination of calcium and insoluble calcium tricalcium, difficult to convert into available phosphorus, the effectiveness is still low. Available phosphorus content as low as 6.8PPm, potential nutrients and available nutrients are lacking. Obviously, “three highs and one low” is the main obstacle to the development of agricultural production in the southern area of agriculture and forestry in southern Xinjiang.