山核桃林土壤养分渗漏动态变化规律研究

Dynamic Changes of Soil Nutrients Leaching in Different Hickory Stands

研究了常规经营下山核桃林土壤养分的渗漏流失规律。结果表明:山核桃渗林漏水中可溶性氮流失是氮素渗漏流失的主要形式,平均可溶性氮含量为10.17 mg/L,占全氮含量的86.3%,其中可溶解性氮峰值达到17.56 mg/L;总磷、可溶性磷平均含量分别为0.65、0.45 mg/L;阳离子渗漏流失c(Ca2+)>c(K+)>c(Mg2+)>c(NH4+);施肥影响渗漏水中养分的浓度,6月初施肥后,各养分输出动态过程可以分为前期浓度出峰期和后期浓度下降稳定期,直至8月底再次施肥,N浓度明显升高,P浓度则不变。

Laws of soil nutrients leaching were researched in different hickory stands with common fertilization. Results showed that dissolved nitrogen was the predominant N form in soil percolating water. Average content of dissolved nitrogen was up to 10.17 mg/L, about 86.3% of the total nitrogen content, and the peak value topped 17.56 mg/L. Average content of total phosphorus and dissolved phosphorus was 0.65 mg/L and 0.45 mg/L Law of cationic concentration was followed by c（Ca2.） 〉 c（K＋） 〉 c（Mg2＋）〉 c （NH4＋）. Fertilization influenced nutrient changes in the water leakage. The process of nutrients export by leaching could be separated into two steps, fluctuation and stable, after fertilization on June. Nitrogen concentration increased significantly, but phosphorus concentration was constant with fertilization on August.