Abstract:

Chloris virgata and Hordeum brevisublatum were reseeded in degraded saline-alkali grassland of Songnen Plain, Heilongjiang Province, with mulching 2.0, 1.5, 1.0 and 0 kg·m^-2(CK)pulverized corn straw at the same time, respectively. During three-year experimental period, the effects on the activities of soil urease, invertase, cellulase enzyme, alkaline phosphatase and catalase were observed. The results showed that reseeding and mulching corn straw could significantly improve the activities of soil enzymes, and the activity increased with treatment duration increasing. According to the average value of soil enzyme activities in the experimental period, reseeding H. brevisublatum was better than C. virgata. The soil enzyme activity was the highest when reseeding H. brevisublatum with mulching corn straw 1.5 kg·m^-2, and the activities of tested five soil enzymes increased by 17.84%, 7.39%, 24.95%, 51.82%, 7.20%, compared with mulching 0 kg·m^-2, respectively. The soil enzyme activity was higher than others when reseeding C. virgata with mulching corn straw 2 kg· m^-2, and the activities of tested five soil enzymes respectively increased by 38.90%, 28.22%, 69.19%, 53.97% and 24.67% compared with mulching 0 kg·m^-2.

Key words: Reseed, Straw mulch, Saline and alkaline grassland, Activity of enzyme

摘要：

在黑龙江省松嫩平原退化盐碱草地,补播虎尾草(Chloris virgata)和野大麦(Hordeum brevisublatum),同时分别覆盖2.0,1.5,1.0和0 kg·m^-2的粉碎玉米(Zea mays)秸秆,连续3年观测土壤脲酶、蔗糖酶、纤维素酶、碱性磷酸酶和过氧化氢酶的活性。结果表明:补播和覆盖秸秆都可显著提高以上5种土壤酶的活性,同时随处理年限增加呈上升趋势。从土壤酶活性的3年均值来看,补播野大麦优于补播虎尾草。补播野大麦同时覆盖秸秆1.5 kg·m^-2的土壤酶活性最高, 与不覆盖相比,以上5种酶活性可分别提高17.84%,7.39%,24.95%,51.82%,7.20%。补播虎尾草同时覆盖秸秆2 kg·m^-2的土壤酶活性较高,与不覆盖相比,以上5种酶活性可分别提高38.90%,28.22%,69.19%,53.97%,24.67%。由此表明覆盖同时补播虎尾草或野大麦能有效的改善土壤生态环境和养分。

关键词: 补播, 秸秆覆盖, 盐碱土壤, 酶活性