CONTAMINATED LAND, ECOLOGICAL ASSESSMENTAND REMEDIATION CONFERENCE SERIES (CLEAR 2012) : ENVIRONMENTAL POLLUTION AND RISK ASSESSMENTS Arbuscular mycorrhizal fungi induced differential Cd and P phytoavailability via intercropping of upland kangkong (Ipomoea aquatica Forsk.) with Alfred stonecrop (Sedum alfredii Hance): post-harvest study Junli Hu & Jintian Li & Fuyong Wu & Shengchun Wu & Zhihong Ye & Xiangui Lin & Ming Hung Wong Received: 21 March 2013 / Accepted: 3 June 2013 / Published online: 25 June 2013 # Springer-Verlag Berlin Heidelberg 2013 Abstract A post-harvest experiment was conducted further to our previous greenhouse pot study on upland kangkong (Ipomoea aquatica Forsk.) and Alfred stonecrop (Sedum alfredii Hance) intercropping system in Cd-contaminated soil inoculated with arbuscular mycorrhizal (AM) fungi. Previous- ly, four treatments were established in the intercropping ex- periment, including monoculture of kangkong (control), intercropping with stonecrop (IS), and IS plus inoculation with Glomus caledonium (IS+ Gc) or Glomus versiforme (IS+ Gv). Both kangkong and stonecrop plants were harvested after growing for 8 weeks. Then, the tested soils were reclaimed for growing post-harvest kangkong for 6 weeks. In the post-harvest experiment, there were no significant dif- ferences between the IS and control treatments, except for a significantly decreased (p <0.05) soil available P concentra- tion with IS treatment. Compared with IS, both IS+ Gc and IS+ Gv significantly decreased (p <0.05) soil DTPA-extractable (phytoavailable) Cd concentrations, but not total Cd, by elevat- ing soil pH, causing significantly lower (p <0.05) Cd concen- trations in both the root and shoot of kangkong. In addition, both Gc and Gv significantly increased (p <0.05) soil acid phosphatase activities and available P concentrations and hence resulted in significantly higher (p <0.05) plant P acquisitions. However, only Gv significantly increased (p <0.05) kangkong yield, while Gc only significantly elevated (p <0.05) the shoot P concentration. It suggested that AM fungi have played key roles in Cd stabilization and P mobilization in the intercropping system, and such positive responses seemed to be sustainable and valuable in post-harvest soils. Keywords DTPA-extractable Cd . Glomus caledonium . Glomus versiforme . Metal stabilization . Phytoremediation . Soil acid phosphatase Introduction Cadmium (Cd) is a non-essential metal element which can cause damage even at very low levels and can enter into food chains easily via plant uptake from contaminated soils Responsible editor: Elena Maestri J. Hu : F. Wu : S. Wu : M. H. Wong (*) Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, People’ s Republic of China e-mail: mhwong@hkbu.edu.hk J. Hu : X. Lin (*) State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing 210008, People’ s Republic of China e-mail: xglin@issas.ac.cn J. Hu : F. Wu : S. Wu : X. Lin : M. H. Wong Joint Open Laboratory of Soil and the Environment, Hong Kong Baptist University & Institute of Soil Science, Chinese Academy of Sciences, East Beijing Road 71, Nanjing 210008, People’ s Republic of China J. Li : Z. Ye State Key Laboratory of Biocontrol, and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Higher Education Mega Center, Guangzhou 510006, People’ s Republic of China F. Wu Faculty of Environmental and Municipal Engineering, Henan University of Urban Construction, Mingyue Road, Pingdingshan 467036, People’ s Republic of China Environ Sci Pollut Res (2013) 20:8457–8463 DOI 10.1007/s11356-013-1903-7