Authors: P J Tomlinson M C Savin P A Moore
Publish Date: 2007/10/02
Volume: 44, Issue: 4, Pages: 613-622
Abstract
Repeated additions of untreated and aluminum sulfate alumtreated poultry litter to soil affect ecology and consequent nutrient dynamics The objective of this study was to determine how repeated annual poultry litter additions affected phosphatase activities in concert with changes in soil phosphorus P Field plots were amended annually since 1995 with either 224 or 896 Mg ha−1 alumtreated AL1 or AL4 respectively or untreated poultry litter PL1 or PL4 respectively or equivalent rates by N content of ammonium nitrate AN1 or AN4 respectively Soil pH total C CTot microbial biomass C doublestranded deoxyribonucleic acid dsDNA MehlichIII P M3P watersoluble P WSP and acid and alkaline phosphatase activities were measured before and 10 days 1 month and 6 months after fertilizer applications in 2003 and 2004 M3P and acid phosphatase activities were higher in AL4 soil than in all other treatments Higher WSP in the untreated compared to the alumtreated litter resulted in higher WSP in the soil amended with untreated litter At the same time alkaline phosphatase activities were significantly higher in PL4 compared to AL4 In contrast alkaline phosphatase activities were significantly lower in AN4 the treatment with the lowest pH Additionally alkaline phosphatase activities expressed per unit CTot or dsDNA remained significantly greater in PL4 and significantly lower in AN4 than all other treatments Thus some factor beyond an increase in soil C or microbial biomass contributed to elevated alkaline phosphatase activities in PL4 despite increased WSP in the treatment receiving the high rate of untreated litterThis research was supported in part by a Southern Region—Sustainable Agriculture Research and Education Program Graduate Student Grant project no GS03030 Arkansas Agricultural Experiment Station Research Incentive Program and the Water Resources Research Institute program through the USGS project no 2003AR47B The authors would like to thank P Nannipieri and anonymous reviewers for their thoughtful reviews of this manuscript as well as Dr Ed Gbur Jerry Martin Scott Becton Kim Payne and all of the other support personnel that helped with this project
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