渭北台塬区荒草地整治后新增耕地土壤肥力调查研究——以陕西澄城为例

Investigation of New Farmland Soil Fertility after Wild Grassland Reclamation in Weibei Plateau: A Case Study in Chengcheng County,Shaanxi Province

[目的]为探讨新增耕地的肥力水平、最大限制因素以及新增耕地的综合肥力指数,并且提出合理的施肥策略。[方法]通过采样分析,采用菲尔德法和加权求和评价法对渭北台塬区荒草地土地整治后新增耕地肥力指标进行分析。[结果]土地整治后新增耕地土壤肥力含量处于较低水平,该研究区域有机质的平均含量为7.8 g/kg,全氮平均含量0.93 mg/kg,有效磷平均含量为4.06 mg/kg,速效钾平均含量为52.3 mg/kg。新增耕地土壤肥力指数分布在25~60分之间,平均得分41分,其中得分在30~40之间的样点约占总数的一半,大于50分的约占17.78%。[结论]土壤有效磷和土壤有机质是渭北台塬区荒草地整治新增耕地肥力指标的最大控制因素。提高土壤有效磷和有机质含量是提高新增耕地肥力综合指数的最直接的方式。有机肥与化肥配施,将是提高新增耕地土壤肥力最有效的途径。

[Objective] The research aimed to explore the value of new farmland soil fertility and the maximum limit factors, as well as the new farmland comprehensive fertility index, and put forward a reasonable fertilization strategy. [ Method ] Through sampling analysis, the new farmland soil fertility index after the wild grassland reclamation by using the method of the Field and Weighted Summation in Weibei Plateau was studied. [ Result] The soil fertility of the new farmland after land reclamation was in a lower level in study area. The organic matter con- tent was 7.8 g/kg, the total nitrogen content was 0.93 mg/kg, the effective phosphorus content was 4.06 mg/kg, and the rapidly-available potassium content was 52.3 mg/kg. The new farmland soil fertility index distribution was 25 - 60 points, and the average score was 41 points. Points between 30 and 40 accounted for about half of the total, and the numbers of samples more than 50 point accounted for about 17.78%. [ Conclusion ] The soil effective phosphorus and the soil organic matter were the biggest control factors of new farmland fertility index. The im- provement of the soil effective phosphorus and soil organic matter content was the most direct way to increase new farmland fertility composite index. Mixed organic manure and chemical fertilizer NPK would be the most effective way to improve new farmland soil fertility.