豌豆茎秆在土壤中的腐解与养分释放特征

Decomposition and Nutrient Release of Pea Stalks in Soil

以‘青豌29号’和‘科豌6号’两种豌豆为绿肥,使用尼龙网袋填埋法进行田间模拟,研究豌豆茎秆还田后在砂姜黑土中的腐解及养分释放特征。结果表明:两种豌豆茎秆在土壤中的腐解表现出前期快、后期慢的特征,还田20 d时累积腐解率超过50%,还田100 d时累积腐解率超过70%;豌豆茎秆中大量元素的释放速率排序为K>N>P,N、K的释放均有快速释放期,P的释放较为平缓;腐解残留物中碳氮比随腐解时间的延长呈降低趋势;中量元素Ca的释放较慢,Mg的释放较快;微量元素Fe、Mn、Cu、Zn的释放均较慢,且腐解残留物中Mn、Cu、Zn均有不同程度的阶段性富集现象。结果可为豌豆绿肥在砂姜黑土还田的应用提供参考。

In order to study decomposition characteristics and nutrient release rules of pea green manures,two pea varieties,‘Qingwan 29’and‘Kewan 6’,were selected as green manure and the nylon mesh bag method was used for decomposition simulation after pea stalks returned to Shajiang black soil.The results showed that decomposition of pea stalks in soil was fast in the early stage but slow in the late stage.The decomposition ratio was more than 50%20 days after return to the field and more than 70%100 days after return to the field.The release ratio rankings of macronutrients in pea stalks were K>N>P;nitrogen and potassium had a rapid release period,while the release of phosphorus was relatively gentle.In the whole decomposition process,the C/N ratios of decomposition residues tended to decrease with prolonging decomposition time.Among medium elements,the release of calcium was slower but that of magnesium was faster.The release of trace elements including iron,manganese,copper and zinc was slow,and manganese,copper and zinc were enriched at different stages except for iron.This study can provide a reference for the application of pea green manures in Shajiang black soil.