应用生态学报2015，Vol.26Issue(1)：1-8,8.
丘陵红壤茶园根际氮磷转化对不同强度酸雨胁迫的响应
Responses of rhizosphere nitrogen and phosphorus transformations to different acid rain intensities in a hilly red soil tea plantation
摘要
Abstract
Tea (Camellia sinensis) plantation in hilly red soil region has been long impacted by acid deposition,however its effects on nitrogen (N) and phosphorus (P) transformations in rhizosphere soils remain unclear.A 25-year old tea plantation in a typical hilly red soil region was selected for an in situ simulation experiment treated by pH 4.5,pH 3.5,pH 2.5 and control.Rhizosphere and bulk soils were collected in the third year from the simulated acid deposition experiment.Soil mineral N,available P contents and major enzyme activities were analyzed using the chemical extraction and biochemical methods,and N and P mineralization rates were estimated using the indoor aerobic incubation methods.Our results showed that compared to the control,the treatments of pH 4.5,pH 3.5 and pH 2.5,respectively decreased 7.1％,42.1％ and 49.9％ NO3--N,6.4％,35.9％ and 40.3％ mineral N,10.5％,41.1％ and 46.9％ available P,18.7％,30.1％ and 44.7％ ammonification rate,3.6％,12.7％ and 38.8％ net N-mineralization rate,and 31.5％,41.8％ and 63.0％ P mineralization rate in rhizosphere soils; however,among the 4 treatments,rhizosphere soil nitrification rate was not significantly different,the rhizosphere soil urease and acid phosphatase activities generally increased with the increasing intensity of acid rain (P＜0.05).In bulk soil,compared with the control,the treatments of pH 4.5,pH 3.5 and pH 2.5 did not cause significant changes in NO3--N,mineral N,available P as well as in the rates of nitrification,ammonification,net N-mineralization and P mineralization.With increasing the acid intensity,the rhizosphere effects of NH4+-N,NO3--N,mineral N,ammonification and net N-mineralization rates were altered from positive to negative effects,those of urease and acid phosphatease showed the opposite trends,those of available P and P mineralization were negative and that of nitrification was positive.In sum,prolonged elevated acid rain could reduce N and P transformation rates,decrease their availability,alter their rhizosphere effects,and have impact on nutrient cycling in tea plantation.关键词
模拟酸雨/氮磷矿化/茶树/根际效应/丘陵红壤区Key words
simulated acid rain/ N and P mineralization/ Camellia sinensis/ rhizosphere effect/hilly red soil region分类
农业科技引用本文复制引用
陈希,陈伏生,叶素琼,喻苏琴,方向民,胡小飞..丘陵红壤茶园根际氮磷转化对不同强度酸雨胁迫的响应[J].应用生态学报,2015,26(1):1-8,8.基金项目
国家自然科学基金项目(31260199,31160107,31060081)、江西省青年科学家培养对象项目(20122BCB23005)和江西省教育厅科技计划项目(GJJ12021)资助. （31260199,31160107,31060081）
