短期放牧干扰对黄土丘陵区生物结皮土壤氮素累积的影响
发布时间：2018-11-22 14:20
【摘要】：通过野外调查结合室内分析,研究了黄土丘陵区模拟放牧干扰半年和一年后生物结皮土壤全氮、速效氮和微生物生物量氮累积的变化,以期揭示生物结皮土壤氮素对干扰响应的敏感性.结果表明:生物结皮土壤氮素对干扰响应敏感,短期干扰可导致土壤全氮、速效氮和微生物生物量氮含量降低.干扰半年后,生物结皮层全氮和速效氮含量较不干扰分别下降0.17~0.39 g·kg~(-1)、1.78~5.65 mg·kg~(-1);干扰一年后,分别下降0.13~0.40 g·kg~(-1)、11.45~32.68 mg·kg~(-1),生物结皮层微生物生物量氮下降69.99~330.97 mg·kg~(-1),0~2 cm土壤微生物生物量氮增加25.51~352.17 mg·kg~(-1).干扰对生物结皮土壤氮素累积的影响与干扰强度有关,20%和30%干扰强度下生物结皮层氮素累积变化不显著,40%和50%干扰强度下生物结皮层氮素累积显著降低.短期干扰降低了生物结皮层氮素累积,但表层5 cm土壤氮素含量变化不显著.
[Abstract]:Through field investigation and laboratory analysis, the changes of total nitrogen, available nitrogen and microbial biomass nitrogen accumulation in biological crust soil under simulated grazing disturbance for half a year or a year in loess hilly region were studied. In order to reveal the sensitivity of biological crust soil nitrogen to interference response. The results showed that nitrogen in biological crust soil was sensitive to interference, and short-term interference could reduce soil total nitrogen, available nitrogen and microbial biomass nitrogen content. After six months of disturbance, the contents of total nitrogen and available nitrogen in the biological cortex decreased by 0.17g kg~ (-1) and 1.785.65 mg kg~ (-1), respectively. After one year of disturbance, the levels of 0.13g kg~ (-1), 11.45 mg kg~ (-1) and 69.99 mg kg~ (-1) of microbial biomass nitrogen were decreased, respectively, and the microbial biomass nitrogen in the biological cortex decreased by 330.97 mg kg~ (-1), respectively. Soil microbial biomass nitrogen increased by 25.51 ~ 352.17 mg kg~ (-1) at 0 ~ 2 cm. The effect of interference on nitrogen accumulation in biological crust soil was related to the intensity of interference. There was no significant change of nitrogen accumulation in biological crust under 20% and 30% interference intensity, while nitrogen accumulation in biological cortex decreased significantly under 40% and 50% interference intensity. Short-term interference reduced the accumulation of nitrogen in the biological cortex, but the soil nitrogen content did not change significantly in the surface layer for 5 cm.
【作者单位】： 西北农林科技大学资源环境学院;中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室;中国科学院大学;
【基金】：国家自然科学基金项目(41571268,41271298)资助~~
【分类号】：S812.2
，
本文编号：2349620
[Abstract]:Through field investigation and laboratory analysis, the changes of total nitrogen, available nitrogen and microbial biomass nitrogen accumulation in biological crust soil under simulated grazing disturbance for half a year or a year in loess hilly region were studied. In order to reveal the sensitivity of biological crust soil nitrogen to interference response. The results showed that nitrogen in biological crust soil was sensitive to interference, and short-term interference could reduce soil total nitrogen, available nitrogen and microbial biomass nitrogen content. After six months of disturbance, the contents of total nitrogen and available nitrogen in the biological cortex decreased by 0.17g kg~ (-1) and 1.785.65 mg kg~ (-1), respectively. After one year of disturbance, the levels of 0.13g kg~ (-1), 11.45 mg kg~ (-1) and 69.99 mg kg~ (-1) of microbial biomass nitrogen were decreased, respectively, and the microbial biomass nitrogen in the biological cortex decreased by 330.97 mg kg~ (-1), respectively. Soil microbial biomass nitrogen increased by 25.51 ~ 352.17 mg kg~ (-1) at 0 ~ 2 cm. The effect of interference on nitrogen accumulation in biological crust soil was related to the intensity of interference. There was no significant change of nitrogen accumulation in biological crust under 20% and 30% interference intensity, while nitrogen accumulation in biological cortex decreased significantly under 40% and 50% interference intensity. Short-term interference reduced the accumulation of nitrogen in the biological cortex, but the soil nitrogen content did not change significantly in the surface layer for 5 cm.
【作者单位】： 西北农林科技大学资源环境学院;中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室;中国科学院大学;
【基金】：国家自然科学基金项目(41571268,41271298)资助~~
【分类号】：S812.2
，
本文编号：2349620
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