我国旱地两熟区土壤养分时空变异的调查研究

旱地两熟区是我国旱作农业重要区域,同时也是主要的粮食产区。本研究基于文献资料查阅、地方测土配方施肥数据收集等方式,分析旱地两熟区农田土壤养分盈缺状况。结果表明:以全国土壤养分含量分级标准为参照,我国旱地两熟区农田土壤养分含量总体达到中等水平,区域间养分含量差异较大,以云南高原最好,江淮丘陵次之,华北平原、黄土高原和川中丘陵最差;与其他粮食主产区土壤肥力相比处于中下等水平;与80年代全国第二次土壤普查数据相比,绝大部分旱地两熟区的农田土壤养分含量明显增加,但对于原始地力较高的云南高原地区,土壤有机质和速效钾含量稍降。在今后的田间管理中合理施肥、秸秆还田和保护性耕作等精细农田管理措施将成为提高该区土壤肥力的关键。

Investigation of Temporal and Spatial Variability of Soil Nutrients in Double Cropping Area of the Upland,China

Double cropping area of the upland was the main grain-producing regions in dry farmland,China.Data collected from the literature reviewing and soil testing and formulated fertilization were used to analysis soil nutrient level in double cropping area of the upland.Results showed that taking the classification standard of soil nutrient content as reference,soil nutrient content was at medium levels in the double cropping area of the upland compared with other area,China.Soil nutrient contents in farmland were significantly higher at present than at the early stage of 1980s.But the contents of soil organic matter and soil available phosphorus decreased slightly in Yunnan plateau.These results indicated that these measures,such as reasonable fertilizer,straw residue incorporation and conservation tillage,were the keys to improve soil nutrient levels.