土壤藻改良退化草地对土壤酶活性的影响

Effects of Soil Algae in Degenerated Grassland Improvement on Soil Enzyme Activities

研究土壤藻生长对退化草地不同埋深土壤p H和土壤酶活性的影响,为利用土壤藻改良退化草地提供重要的理论依据。采集野外未接种与接种土壤藻区域不同年限(0、1、2、3 a)退化草地不同埋深(0~10、10~20、20~30和30~50 cm)土壤样品,测定土壤的p H值和土壤酶活性。结果表明,土壤藻的生长使不同埋深土壤p H降低,但仍然保持弱碱性;人工土壤藻结皮的形成和发育使与碳素、氮素和磷素循环有关的土壤酶活性增强,但对不同土壤酶活性的影响具有一定的差异。土壤藻结皮发育时间越长,对土壤酶活性影响越强,但随着土壤埋深的增加而减弱。土壤藻在形成生物结皮的过程中,土壤酶的活性增强,加速了环境中碳、氮和磷的循环,从而促进退化草地的恢复。

To provide an important theoretical basis for improving degenerated grassland with soil algae, the effects of soil algae growth on p H and soil enzyme activities were investigated by analyzing soil simples at different depths collecting from degenerated grassland improvement region. The soil simples at different depths（0-10, 10-20, 20-30 and 30-50 cm） collected from different improvement time（0, 1, 2 and 3 years） in degenerated grassland were used to test the p H values and several soil enzyme activities. The results indicated that algal growth lowered the p H values of soil at different depths, but still at weak alkaline levels. The activities of soil enzymes related to carbon, nitrogen and phosphorus cycles increased with the formation and development of man-made soil algal crusts. Moreover, there were obvious differences in the effects on diverse soil enzymes. The activities of soil enzymes enhanced with the development extension of man-made soil algal crusts. However, they decreased with the depth of soil increasing. Enhanced activities of soil enzymes during the growth of soil biological crusts accelerated carbon, nitrogen and phosphorus cycles, and promoted the restoration of degenerated grassland.