Differences in Soil Microbial Biomass and Activity for Six Agroecosystems with a Management Disturbance Gradient
Different management practices in six agroecosystems located near Goldsboro, NC, USA were conducted including a successional field (SU), a plantation woodlot (WO), an integrated cropping system with animals (IN), an organic farming system (OR), and two cash-grain cropping systems employing either tillage (CT) or no-tillage (NT) to examine if and how microbial biomass and activity differ in response to alterations in disturbance intensity from six land management strategies. Results showed that soil microbial biomass and activity differed, with microbial activity in intermediately disturbed ecosystems (NT, OR, IN) being significantly higher (P ＜ 0.01) than systems with either high or low disturbance intensities. There was also a significant and a highly significant ecosystem effect from the treatments on microbial biomass C (MBC) (P ＜ 0.05) and on microbial activity (respiration) (P ＜ 0.01), respectively. Multiple comparisons of mean respiration rates distinctly separated the six ecosystem types into three groups: CT ＜ NT, SU and WO ＜ OR and IN.Thus, for detecting microbial response to disturbance changes these results indicated that the active component of the soil microbial community was a better indicator than total biomass.
作 者： ZHANG Wei-Jian FENG Jin-Xia J.WU K.PARKER 作者单位： ZHANG Wei-Jian(Department of Agronomy,Nanjing Agricultural University,Nanjing 210095,China; Department of Plant Pathology,North Carolina State University,Raleigh,NC 27695,USA)FENG Jin-Xia(Department of Agronomy,Nanjing Agricultural University,Nanjing 210095,China)
J.WU,K.PARKER(Department of Plant Pathology,North Carolina State University,Raleigh,NC 27695,USA)
刊 名： 土壤圈（意译名） ISTIC SCI 英文刊名： PEDOSPHERE 年，卷(期)： 2004 14(4) 分类号： P5 关键词： agroecosystems carbon retention disturbance intensity microbial biomass soil microbial activity