生物炭与腐殖酸配施对盐碱土理化性质的影响

Effect of biochar and humic acid on physical and chemical properties of saline-alkali soil

为探索新型盐碱化土壤改良剂,选取玉米秸秆、葵花秸秆制成生物炭与腐殖酸配合,研究玉米秸秆生物炭(A)、混合秸秆生物炭(A1)、腐殖酸(B)、玉米秸秆生物炭+腐殖酸(AB)、混合秸秆生物炭+腐殖酸(A1B)5种改良剂与土壤混合后较对照组原土(CK)中盐碱指标、肥力指标的改善情况。结果表明:生物炭和腐殖酸都具有改良土壤盐碱性、提高土壤肥力的作用,二者联合配施对降低土壤pH、电导率(EC)、碱化度(ESP)及提高土壤养分的效果更明显,其中混合生物炭与腐殖酸配施(A1B)效果最好,A1B组处理的土壤pH较CK组显著降低10.8%,EC下降55%,ESP降低9.8%;速效钾、有效磷、速效氮及有机质的平均增幅较其他4个处理分别提升59.77%、210%、178%、180%。综上所述,混合施用生物炭及腐殖酸对于改良盐碱土效果明显。

In order to explore a new type of saline-alkali soil amendment,corn and sunflower straws were selected to make biochar and humic acid.Five amendment types including corn straw biochar(A),mixed straw biochar(A1),humic acid(B),corn straw biochar+humic acid(AB),mixed straw biochar+humic acid(A1B),were mixed with the soil and also the original soil as CK.Then,the improvement of medium saline-alkali index and fertility index were evaluated.The results showed that both biochar and humic acid improved soil salinity and fertility.The combined application of biochar and humic acid had more obvious effects on soil pH,electrical conductivity(EC),exchangeable sodium percentage(ESP),and soil nutrients.The effect of mixed biochar and humic acid(A1B)was the best.Compared with CK group,the soil pH of A1B group significantly decreased by 10.8%,while the EC decreased by 55.0%,and ESP decreased by 9.8%.The available K,P,N,and organic matter of A1B increased by 59.77%,210%,178%,and 180%,respectively.In summary,mixed application of biochar and humic acid had a significant effect on improving saline-alkali soil.