title: Soil acidification increases metal extractability and bioavailability in old orchard soils of Northeast Jiaodong Peninsula in China.
abstract: The bioavailability of Cu, Zn, Pb and Cd from field-aged orchard soils in a certified fruit plantation area of the Northeast Jiaodong Peninsula in China was assessed using bioassays with earthworms (Eisenia fetida) and chemical assays. Soil acidity increased with increasing fruit cultivation periods with a lowest pH of 4.34. Metals were enriched in topsoils after decades of horticultural cultivation, with highest concentrations of Cu (132 kg(-1)) and Zn (168 mg kg(-1)) in old apple orchards and Pb (73 mg kg(-1)) and Cd (0.57 mg kg(-1)) in vineyard soil. Earthworm tissue concentrations of Cu and Pb significantly correlated with 0.01 M CaCl2-extractable soil concentrations (R(2) = 0.70, p < 0.001 for Cu; R(2) = 0.58, p < 0.01 for Pb). Because of the increased bioavailability, regular monitoring of soil conditions in old orchards and vineyards is recommended, and soil metal guidelines need reevaluation to afford appropriate environmental protection under acidifying conditions.
authors.affiliation: Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China.
authors.forename: Lianzhen
authors.initials: L
authors.lastname: Li
authors.affiliation: Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China. Electronic address: hfwu@yic.a.cn.
authors.forename: Huifeng
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Ecological Science, Faculty of Earth and Life Sciences, VU University, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands. Electronic address: kees.van.gestel@vu.nl.
authors.forename: Cornelis A M
authors.initials: CA
authors.lastname: van Gestel
authors.affiliation: National Institute of Public Health and The Environment, Laboratory for Ecological Risk Assessment, P.O. Box 1, 3720 BA Bilthoven, The Netherlands; Institute of Environmental Sciences (CML), Leiden University, Leiden, The Netherlands.
authors.forename: Willie J G M
authors.initials: WJ
authors.lastname: Peijnenburg
authors.affiliation: Department of Civil and Environmental Engineering, University of Delaware, Newark, DE 19716, USA.
authors.forename: Herbert E
authors.initials: HE
authors.lastname: Allen
mesh_terms: D000383:Agriculture; D000818:Animals; D002681:China; D008670:Metals / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D009835:Oligochaeta / Q000378:metabolism; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism
chemical_list: D008670:Metals; D012987:Soil; D012989:Soil Pollutants
keywords: Earthworm; Metal bioavailability; Orchard; Soil acidification; Vineyard