不同恢复措施对若尔盖沙化退化草地恢复过程中土壤微生物生物量碳氮及土壤酶的影响

发布时间：2018-04-10 01:36

  本文选题：若尔盖高原　切入点：沙化　出处：《生态环境学报》2017年03期

【摘要】：若尔盖高原是长江、黄河上游重要的水源地之一。近年来由于人类活动及气候变化等原因,其草地出现了严重的沙化退化现象。通常认为在返青季节对沙化退化草地进行补播后,完全围封有助其恢复,但在实践中发现,补播后对其进行放牧,恢复效果更理想。因此,选取若尔盖典型沙化退化草地,对比分析了合理放牧、围封禁牧与自然恢复3种恢复措施对土壤微生物生物量碳氮、土壤酶活(酸性土壤磷酸酶、多酚氧化酶、过氧化物酶、β-1,4-葡萄糖苷酶及β-1,4-N-乙酰葡萄糖苷酶)及土壤碳氮矿化速率的影响。结果显示,恢复6年后:与围封禁牧和自然恢复相比,合理放牧恢复草地土壤微生物生物量碳[C(101.27±22.14)mg·kg~(-1)]、生物量氮[N(67.45±18.02)mg·kg~(-1)]、土壤酸性磷酸酶活[(159.0±36.4)μg·g~(-1)·h-1]、β-1,4-葡萄糖苷酶活[(81.19±16.78)nmol·g~(-1)·h~(-1)]、碳矿化速率[C(25.19±5.79)g·kg~(-1)·d~(-1)]以及氮矿化速率[N(0.476±0.015)mg·kg~(-1)·d~(-1)]显著提高;围封禁牧恢复草地除土壤β-1,4-葡萄糖苷酶活[(29.91±14.39)nmol·g~(-1)·h~(-1)]及氮矿化速率[N(0.172±0.050)mg·kg~(-1)·d~(-1)]外,其余指标与自然恢复无显著差异;在相关性研究中,土壤氮矿化速率与微生物生物量碳氮、酸性磷酸酶活、β-1,4-葡萄糖苷酶活呈极显著相关(P0.01);微生物生物量碳氮与酸性磷酸酶活呈极显著相关(P0.01),与β-1,4-葡萄糖苷酶活呈显著相关(P0.05)。结果表明:在若尔盖沙化草地的恢复过程中,合理放牧是一种科学的沙化草地恢复措施。
[Abstract]:The Ruoergai Plateau is one of the most important sources of water in the upper reaches of the Yellow River and the Yangtze River.In recent years, due to human activities and climate change, the grassland has been degraded seriously.It is generally considered that the complete enclosure is helpful for the restoration of degraded sandy grassland after supplementary sowing in the returning green season, but in practice it is found that the restoration effect is better after grazing after the replacement sowing.Therefore, the soil microbial biomass, carbon nitrogen, soil enzyme activity (acid soil phosphatase, polyphenol oxidase) were compared and analyzed in three restoration measures, I. e., rational grazing, enclosed forbidding grazing and natural restoration in the typical desertified degraded grassland of Zoige.Effects of peroxidase, 尾 -1n 4-glucosidase and 尾 -1n 4-N acetyl glucosidase) and soil carbon and nitrogen mineralization rate.The results showed that, after 6 years of restoration: compared with closed grazing and natural recovery,鍚堢悊鏀剧墽鎭㈠�嶈崏鍦板湡澹ゅ井鐢熺墿鐢熺墿閲忕⒊[C(101.27卤22.14)mg路kg~(-1)],鐢熺墿閲忔爱[N(67.45卤18.02)mg路kg~(-1)],鍦熷￥閰告，

本文编号：1729110