10年氮添加未显著影响苦竹林土壤磷组分  

Ten-year Nitrogen Addition Did Not Significantly Affect Soil Phosphorus Fractions in A Pleioblastus amarus Plantation

作　　者：陈雨芩 陈冠陶 梁政 李仁洪[3] 马豪宇 涂利华[1] CHEN Yuqin;CHEN Guantao;LIANG Zheng;LI Renhong;MA Haoyu;TU Lihua(College of Forestry,Sichuan Agricultural University,Chengdu 611130,China;Forestry Inventory and Plan Institute of Liangshan State,Xichang 615000,China;Sichuan Forestry Inventory and Planning Institute,Chengdu 610081,China)

机构地区：[1]四川农业大学林学院,四川成都611130 [2]四川省凉山州林业调查规划设计院,四川西昌615000 [3]四川省林业调查规划院,四川成都610081

出　　处：《生态环境学报》2018年第4期677-684,共8页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(31300522)

摘　　要：土壤磷(P)的可利用性是影响植物生长发育的重要因素。以研究氮(N)添加对土壤P组分的影响为切入点,探讨长期N沉降增加对竹林生态系统中土壤P素可利用性及P循环的影响,对预测该区域大气N沉降持续增加背景下人工竹林系统P素状态的变化具有重要意义。于2007年10月在苦竹(Pleioblastus amarus)林中建立模拟N沉降试验样地,设置对照(CK,0g·m^(-2)·a^(-1))、低N(LN,5g·m^(-2)·a^(-1))、中N(MN,15g·m^(-2)·a^(-1))和高N(HN,30g·m^(-2)·a^(-1))4个处理,每个处理设置3个重复。从2007年10月—2017年10月,每月下旬进行N添加处理。在连续N添加处理10a后,于2017年4月采集0~10cm土壤样品并测定土壤P组分、土壤微生物生物量P含量、土壤酸性磷酸酶活性及土壤pH。结果表明:该苦竹林土壤总P质量分数为0.64mg·g^(-1),其中残渣P约占77.0%,有机P占15.0%,无机P占8.0%。CK处理下,碳酸氢钠和氢氧化钠提取的无机P组分(NaHCO3-Pi和NaOH-Pi)质量分数分别为0.26mg·kg^(-1)和4.26mg·kg^(-1),N处理分别使其增加了100.0%~157.7%和43.2%~70.0%,但未达到统计学显著水平(P>0.05)。另外,N添加处理未显著影响土壤pH、土壤酸性磷酸酶活性和土壤微生物生物量P(P>0.05)。研究结果表明,长期N添加未显著影响苦竹林土壤酸性磷酸酶活性、土壤总P含量以及各个P组分的分配(P>0.05),这说明长期N添加未显著影响土壤P素可利用性。在未来一段时间内,该林分的P素循环可能不会受到大气N沉降增加的强烈影响。The availability of soil phosphorus(P)is an important factor in plants growth and development.The effect of increased nitrogen(N)on soil P fractions,the effect of the long-term N deposition on soil P availability and P cycle was investigated in a bamboo forest ecosystem.It is of great significance to predict the change of soil P state in the artificial bamboo forest system in the case of continuous increase of atmospheric N deposition in the region.A simulated N deposition experiment was conducted in the bamboo forest of Pleioblastus amarus since October 2007.Four treatments were installed,i.e.,control(0 g·N·m-2·a-1),low nitrogen(5 g·N·m-2·a-1),medium nitrogen(15 g·N·m-2·a-1)and high nitrogen(30 g·N·m-2·a-1).Each treatment with three replications were designed.The site was applied N at the end of each month from October 2007 to October 2017.After 10 years of continuous addition of N,soil samples collected from the 0?10 cm horizon in the P.amarus plantation were used to analyze the soil P fractions,soil microbial biomass P,soil acid phosphatase activity and the soil pH value in April 2017.The results showed that the content of total P was 0.64 mg·g-1,of which the residual P was about 77%,and the organic P was 15.5%,the inorganic P was 8.0%.The content of NaHCO3-Pi and NaOH-Pi was respectively 0.26 mg·kg-1 and 4.26 mg·kg-1 with control treatment,and their content increased by 100.0%~157.7%and 43.2%~70.0%in N addition plots respectively,but they did not reach a statistically significant level(P>0.05).In addition,N addition did not significantly affect the soil pH value,soil acid phosphatase activity and soil microbial biomass P(P>0.05).Our results thus indicate that the effect of the long-term addition of N did not significantly affect the soil acid phosphatase activity,soil total P and the distribution of each P fractions in the P.amarus plantation(P>0.05).It thus indicates that the effect of the long-term addition of N on the soil P element availability was not significant.For some time to come,the

关 键 词：N添加 P组分 P循环 苦竹 

分 类 号：S714[农业科学—林学] X144[环境科学与工程—环境科学]