石羊河中下游不同退耕年限次生草地土壤无机氮、酶及微生物量冬季动态研究

发布时间：2018-05-17 02:42

  本文选题：石羊河中下游 + 草地土壤　； 参考：《草地学报》2016年02期

【摘要】：为研究石羊河中下游退耕区次生草地冬季土壤肥力状况和微生物机制,测定并分析了石羊河中下游不同退耕年限和不同土层深度土壤无机氮(硝态氮、铵态氮)、酶活性(过氧化氢酶、脲酶、磷酸酶及蔗糖酶)及微生物生物量冬季动态变化。结果表明,研究区各土层(0~10,10~20,20~30,30~40cm)土壤铵态氮与硝态氮随退耕年限不同逐年递增;除30~40cm土层外,各土层土壤微生物量碳在退耕较短年限内(1~5a)总体逐年递减,而在退耕较长年限内(8~31a)逐年递增;土壤微生物量氮随恢复年限呈先下降(1~4a)、后稳定(4~15a)再上升(15~31a)的趋势;各土层土壤微生物量磷则呈先上升,后下降,再上升的趋势;不同退耕年限间土壤过氧化氢酶活性差异不显著,脲酶、磷酸酶及蔗糖酶活性差异显著(P0.05),土壤酶活性总体随土层加深而降低。本试验为石羊河流域的植被恢复、土壤改良和科学管理提供了科学依据。
[Abstract]:In order to study the soil fertility and microbial mechanism of secondary grassland in the middle and lower reaches of Shiyang River in winter, the soil inorganic nitrogen (nitrate nitrogen) was measured and analyzed in different returning years and different soil depths of Shiyang River in the middle and lower reaches of Shiyang River. The dynamic changes of ammonium nitrogen, enzyme activity (catalase, urease, phosphatase and sucrase) and microbial biomass in winter. The results showed that the soil ammonium nitrogen and nitrate nitrogen increased year by year, except for 30~40cm soil layer, the soil microbial biomass carbon decreased year by year in a short period of time, except for 30~40cm soil layer, soil ammonium nitrogen and nitrate nitrogen increased year by year, except for 30~40cm soil layer, the soil ammonium nitrogen and nitrate nitrogen increased year by year, with the exception of 30~40cm soil layer, the soil microbial biomass carbon in each soil layer decreased year by year. The soil microbial biomass nitrogen (microbial biomass nitrogen) decreased firstly with the restoration years, then stabilized at 4 ~ 15 a) and then increased to 15 ~ 31a), and the soil microbial biomass phosphorus increased first, then decreased, and then increased. There was no significant difference in soil catalase activity among different returning years, but the difference of urease, phosphatase and sucrase activity was significant (P0.05), and the soil enzyme activity decreased with the deepening of soil layer. This experiment provides scientific basis for vegetation restoration, soil improvement and scientific management in Shiyang River Basin.
【作者单位】： 甘肃农业大学草业学院/草业生态系统教育部重点实验室/甘肃省草业工程实验室/中-美草地畜牧业可持续发展研究中心;甘肃省治沙研究所;甘肃河西走廊森林生态系统国家定位观测研究站/甘肃省荒漠化与风沙灾害防治国家重点实验室培育基地;
【基金】：国家自然科学基金-人为干预下石羊河下游地下水动态变化及生态效应研究(31260129);石羊河中下游退耕地土壤系统演变规律及其驱动机制研究(41161049);荒漠区沙生针茅种子萌发机理研究(31160264)资助
【分类号】：S812.2
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本文编号：1899570