覆盖秸秆和补播牧草对松嫩平原退化盐碱草地土壤酶活性的影响

Influence of Straw Covering and Reseeding on Soil Enzyme Activity in Saline and Alkaline Grassland in Songnen Plain

在黑龙江省西部松嫩平原退化盐碱草地,分别对补播东饲1号稗草和星星草草地进行覆盖粉碎玉米秸秆2kg/m2、1.5kg/m2和1.0kg/m2,以不覆盖秸秆为对照(0kg/m2),连续三年监测土壤脲酶、蔗糖酶、纤维素酶和碱性磷酸酶活性。结果表明:补播牧草和覆盖秸秆可连续提高以上四种土壤酶活性,总体上补播星星草土壤酶活性高于补播稗草。补播星星草同时覆盖秸秆1.5kg/m2,土壤脲酶、蔗糖酶、纤维素酶和碱性磷酸酶活性三年均值均最高,分别比对照提高16.99%、18.54%、24.92%和41.49%;补播稗草同时覆盖秸秆,随着覆盖量的增加土壤脲酶、蔗糖酶和纤维素酶活性呈上升趋势,但土壤碱性磷酸酶活性在覆盖1.5kg/m2时三年均值达到最高,比对照提高36.42%。由此表明,覆盖秸秆和补播牧草能有效改善土壤生态环境和养分。

Echinochloa crusgalli,Puccinellia tenuiflora were reseeded and was covered with maize straw 2 kg/m2,1.5 kg/m2 and 1.0 kg/m2 respectively in saline-alkali land in Songnen plain in the west of Heilongjiang province compared with no covering maize straw for control（0 kg/m2）,the activity of urease,sucrase,cellulase and alkaline phosphatase were tested for three years.The experiment result showed as follows：the active of four soil enzymes was significantly increased by both reseeding forage and covering maize straw.Generally,the soil enzyme activity of reseeding P.tenuiflora was higher than E.crusgalli.Covered with maize straw of 1.5kg/m2 and reseeding P.tenuiflora,the average value of the activity of urease,sucrase,cellulose and phosphatase were the highest,improving by 16.99%,18.54%,24.92% and 41.94-% respectively compared to control.When reseeding E.crusgalli and covering maize straw,the activity of urease,sucrase,cellulose showed an upward trend as the straw cover amount was increasing,however,the phosphatase activity reached the peak of three-year average,increased by 36.42% than control.It showed that covering maize straw and reseeding can effectively improve the ecological environment and soil nutrients.