不同轮作方式下高原山地红壤肥力变化特征

Effects of Different Rotation Systems on Variation in Soil Fertility in Upland Red Soil of Yunnan Plateau

不同轮作方式对土壤肥力具有重大影响．以未开垦利用的荒草地（A）为对照，研究不同轮作方式对高原山地红壤肥力的影响．结果表明：长期实行玉米与冬季绿肥轮作（E）对改善土壤物理性能、提高土壤有机质含量和养分，优于单季玉米种植后冬闲地（B）、玉米与冬季小麦轮作地（C）及玉米与冬季绿肥套种（D）．E地与A，B，C，D地比较：在0～20 cm土层内，土壤有机质含量分别提高24．92，29．22，32．37，6．09g／kg；碱解N含量分剐提高54．32，64．81，73．71，11．14mg／kg；速效P含量分别提高6．06，5．81，7．43，1．12mg／kg；速效K含量分别提高53．53，66．69，84．11，12．48mg／kg．因此，科学利用冬季绿肥轮作，是高原山地红壤改良培肥、抑制土壤肥力退化进程的一项有效措施．

Different rotation systems have significant effect on soil fertility. In a study reported in this paper, no-cultivation meadow （A） was used as control sample to study the efect of rotation systems on soil fertility of upland red soil in Yunan plateau. The results showed that the maize-winter green manure system （E） was better in improvement of soil physical properties, organic matter and chemical fertility than the maize-winter fallow system （B）, maize-winter wheat rotation system （C） and intercropping maize with winter green manure （D）. Compared with systems A, B, C and D, orgamc matter, available N, available phosphorus and available potassium in system E increased by 24. 92 g/kg, 29.22 g/kg, 32. 37 g/kg and 6.09 g/kg;54. 32 mg/kg, 64.81 mg/kg, 73.71 mg/kg and 11.14 mg/kg; 6.06 mg/kg, 5.81 mg/kg, 7.43 mg/kg and 1.12 mg/kg;and 53.53 mg/kg, 66.69 mg/kg, 84.11 mg/kg and 12.48 mg/kg, respectively, in the 0-20 cm soil layer. It is, therefore, concluded that scientific usage of green manure in the rotation system is an effective measure to improve the fertility of upland red soil in plateau regions.