Application of organic amendments to restore degraded soil: effects on soil microbial properties Jennifer Carlson & Jyotisna Saxena & Nicholas Basta & Lakhwinder Hundal & Dawn Busalacchi & Richard P. Dick Received: 21 April 2014 /Accepted: 11 January 2015 /Published online: 12 February 2015 # Springer International Publishing Switzerland 2015 Abstract Topsoil removal, compaction, and other prac- tices in urban and industrial landscapes can degrade soil and soil ecosystem services. There is growing interest to remediate these for recreational and residential purposes, and urban waste materials offers potential to improve degraded soils. Therefore, the objective of this study was to compare the effects of urban waste products on microbial properties of a degraded industrial soil. The soil amendments were vegetative yard waste compost (VC), biosolids (BioS), and a designer mix (DM) containing BioS, biochar (BC), and drinking water treatment resid- ual (WTR). The experiment had a completely random- ized design with following treatments initiated in 2009: control soil, VC, BioS-1 (202 Mgha -1 ), BioS-2 (403 Mg ha -1 ), and DM (202 Mg BioS ha -1 plus BC and WTR). Soils (0–15-cm depth) were sampled in 2009, 2010, and 2011 and analyzed for enzyme activities (arylsulfatase, β-glucosaminidase, β-glucosidase, acid phosphatase, fluorescein diacetate, and urease) and soil microbial community structure using phospholipid fatty acid analysis (PLFA). In general, all organic amendments increased enzyme activities in 2009 with BioS treatments having the highest activity. However, this was followed by a decline in enzyme activities by 2011 that were still significantly higher than control. The fungal PLFA bio- markers were highest in the BioS treatments, whereas the control soil had the highest levels of the PLFA stress markers (P <0.10). In conclusion, one-time addition of VC or BioS was most effective on enzyme activities; the BioS treatment significantly increased fungal biomass over the other treatments; addition of BioS to soils de- creased microbial stress levels; and microbial measures showed no statistical differences between BioS and VC treatments after 3 years of treatment. Keywords Degraded soil . Organic amendments . Microbial properties . Soil enzyme activities Abbreviations BC Biochar BioS Biosolids VC Vegetative yard waste compost DM A designer mix WTR Drinking water treatment residual FDA Fluorescein diacetate PLFA Phospholipid fatty acid Introduction Industrial and urban Bdevelopment^ and intensive agri- cultural practices have caused reduction in soil quality Environ Monit Assess (2015) 187: 109 DOI 10.1007/s10661-015-4293-0 J. Carlson : J. Saxena : N. Basta : R. P. Dick (*) School of Environment and Natural Resources, The Ohio State University, 2021 Coffey Road, Columbus, OH 43210, USA e-mail: richard.dick@snr.osu.edu L. Hundal Monitoring and Research Department, Metropolitan Water Reclamation District of Greater Chicago, 6001 W Pershing Road, Cicero, IL 60804, USA D. Busalacchi Ohio Environmental Protection Agency, Columbus, OH 43216, USA