南方丘陵山地适用性测土配方施肥技术体系

为探明改进测土配方施肥技术在南方丘陵山地农业区的适用性,以重庆市合川区主要农用地测土配方施肥为例,用土壤发生学理论,对研究区2 156个土壤样品的测定结果进行分析,研究南方丘陵山地农地土壤肥力主导因子及各指标测定值间的关联性。结果表明:研究区内土壤以强淋溶为主导发育因子,土壤普遍酸化,pH≤6.5的样本占总样本的比例达81.4%;土壤有机质含量平均为15.8g/kg,水稻土平均为17.9g/kg,大于紫色土(13.4g/kg);土壤全氮平均为0.943g/kg,碱解氮为97.3mg/kg,水稻土全氮和碱解氮含量水平均显著高于紫色土;土壤全磷平均含量为0.54g/kg,有效磷平均含量为16.0mg/kg,水稻土有效磷平均含量为9.5mg/kg,不足紫色土平均含量21.1mg/kg的1/2。研究区水稻土与紫色土的土壤有机质与全氮、碱解氮含量间均具有极显著相关性,土壤全氮和碱解氮水平可由有机质含量推测计算。

Applicability of Soil Testing and Fertilizer Recommendation Technology in Hilly Area of Southern China

2 156 soil samples from main farmland in Hechuan District were analyzed and the correlations between main factor of soil fertility and measured values of different index were studied based on the theory of soil genesis to improve the applicability of soil testing and fertilizer recommendation technology in hilly area of southern China.Results:The leading development factor of soil is strong leaching in the tested area and the proportion of soil samples with pH≤6.5 in total soil samples reaches 81.4％.The average organic matter content of soil,paddy soil and purple soil is 15.8 g/kg,17.9 g/kg and 13.4 g/kg respectively.The average content of soil total nitrogen and available nitrogen is 0.943 g/kg and 97.3 mg/kg separately.The average total nitrogen and available nitrogen content of paddy soil is higher than purple soil significantly.The average content of soil total phosphorus and available phosphorus is 0.54 g/kg and 16.0 mg/kg separately.The average content of available phosphorus in paddy soil was 9.5 mg/kg,which is less than half of that in purple soil (21.1 mg/kg).The soil organic matter is related to total nitrogen and available nitrogen in paddy and purple soil very significantly.Therefore,the soil total nitrogen and available nitrogen level can be calculated by analyzing soil organic matter content.