Title: Temporal Change of Soil Phosphorus Fractions Observed by Field Microplot Cylinder Experiments Authors
Submitted to: World Congress of Soil Science
Publication Type: Abstract Only
Publication Acceptance Date: February 15, 2006
Publication Date: July 9, 2006
Citation: He, Z., Honeycutt, C.W., Griffin, T.S., Fortuna, A. 2006. Temporal change of soil phosphorus fractions observed by field microplot cylinder experiments. World Congress of Soil Science. July 9-15, 2006 Abstracts. p. 538. Technical Abstract: Runoff from high P soils may contribute to surface water eutrophication. Thus, P availability from animal manures should be considered when prescribing manure application rates and timing to optimize P uptake by plants while minimizing adverse environmental impacts. We have used laboratory incubations to evaluate P dynamics in soils amended with animal manure. This study was conducted to compare laboratory with field observations of P availability from animal manure. Soils amended with animal manure were packed in microplot cylinders and installed in fallow fields. Changes in both inorganic P(Pi) and total extractable P(Pt)were similar for both dairy manure–amended and control soils, indicating that soil properties played a major role in controlling P dynamics in these field soils. This observation was similar to that found in laboratory incubation experiments. However, where water extractable P remained relatively constant in the laboratory, significant changes were observed in the field. We attribute these changes to the impacts of variable environmental factors in the field (such as temperature and rainfall). This observation indicates that laboratory incubation may be limited in usefulness for predicting available P from manure under field conditions.