N添加对油松幼苗土壤酶活性和微生物生物量的影响

发布时间：2018-05-19 20:38

本文选题：N添加 + 油松幼苗　；参考：《生态学杂志》2016年02期

【摘要】：通过连续6年对盆栽油松(Pinus tabuliformis)幼苗进行不同水平N添加(0、2.8、5.6、11.2、22.4和44.8 g N·m~(-2)·a~(-1)),研究了N添加对土壤酶活性(蔗糖酶、脲酶和碱性磷酸酶)和微生物生物量碳、氮的影响。结果表明:N添加水平低于11.2 g N·m~(-2)·a~(-1)时,对油松幼苗土壤蔗糖酶和脲酶活性均有促进作用,但过量N添加,尤其超过22.4 g N·m~(-2)·a~(-1)时,蔗糖酶、脲酶和碱性磷酸酶活性均不再提高,甚至表现为抑制作用;N添加为5.6 g N·m~(-2)·a~(-1),微生物生物量碳显著增加,微生物生物量氮无显著变化,而当N添加达到11.2 g N·m~(-2)·a~(-1)时,微生物生物量氮呈显著增加的趋势;土壤蔗糖酶、脲酶活性与微生物生物量碳和微生物生物量氮间均有显著相关关系,而3种酶活性间、微生物生物量碳、氮间均无显著相关性;土壤酶活性和微生物生物量与地上生物量、土壤有机碳和全氮含量显著相关。油松在5.6~11.2 g N·m~(-2)·a~(-1)水平下生长达到最佳。目前黄土高原地区N沉降水平(2.06 g N·m~(-2)·a~(-1))有利于该地区油松林生长;可以通过适当增施N肥的方式提高油松生长。
[Abstract]:The effects of N supplementation on soil enzyme activity (sucrase, urease and alkaline phosphatase) and microbial biomass carbon and nitrogen were studied in potted Pinus tabuliformis seedlings at different levels. The results showed that the activity of sucrase, urease and alkaline phosphatase in the soil of Pinus tabulaeformis seedlings were promoted when the addition level of N was less than 11.2 g N ~ (-2) a ~ (-1), but the activities of sucrase, urease and alkaline phosphatase were no longer increased when the addition of excessive N, especially more than 22.4 g N ~ (2) N ~ (-2) A ~ (-1) ~ (-1), increased the activity of sucrase, urease and alkaline phosphatase. Even if the inhibitory effect of N was 5.6 g / m ~ (-2) / a ~ (-1) N, microbial biomass carbon increased significantly, but microbial biomass nitrogen did not change significantly, but when N concentration reached 11.2 g / m ~ (-2) / a ~ (-1), microbial biomass nitrogen increased significantly, soil sucrose enzyme, soil sucrose enzyme, Urease activity was significantly correlated with microbial biomass carbon and microbial biomass nitrogen, while soil enzyme activity, microbial biomass and aboveground biomass were not significantly correlated with microbial biomass. Soil organic carbon and total nitrogen content were significantly correlated. The optimum growth of Pinus tabulaeformis was obtained at 5.6g / g NM ~ (2) A ~ (-1) ~ (-1). At present, the N deposition level of 2.06 g N ~ m ~ (2) A ~ (-1) ~ (-1) is beneficial to the growth of Pinus tabulaeformis forest in the Loess Plateau, and the growth of Pinus tabulaeformis can be improved by the appropriate application of N fertilizer.
【作者单位】：西北农林科技大学资源与环境学院;西北农林科技大学水土保持研究所;中国科学院水土保持与生态环境研究中心;
【基金】：国家自然科学基金项目(41371508) 西北农林科技大学重大项目培育专项(ZD2013021) 陕西省自然科学基础研究计划重点项目(2013JZ006)资助
【分类号】：S714.3;S791.254

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