Publication Date
1997
Description
The effect of agropastoral systems replacing native savanna on microbially bound phosphorus (Pmic) in low P acid soils was investigated. Chloroform released P (PChl) was measured to estimate Pmic. In a long-term improved pasture experiment, PChl was higher in grass-legume (GL) than grass-only pasture (GO). Although the P balance was slightly higher in GO than in GL, available P contents followed the same trend as PChl suggesting that the presence of legumes enhances the maintenance of P fertility. In a rice-pasture system, PChl was higher than under rice monocrop indicating an effect of the cropping system on PChl that goes beyond P inputs, and includes factors such as soil cultivation, herbicide application and organic matter input. Pmic may not be seen as a factor competing for plant available P in these strongly P-sorbing soils, but as a rapidly cycling pool that protects P from sorption. The results suggest that Pmic is an important indicator of P fertility on low P acid soils.
Citation
Oberson, A; Friesen, D K.; Morel, C; Tiessen, H; and Frossard, E, "Effects of Agropastoral Systems on Microbially Bound Phosphorus in Low P Acid Soils" (2024). IGC Proceedings (1993-2023). 16.
https://uknowledge.uky.edu/igc/1997/session10/16
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Effects of Agropastoral Systems on Microbially Bound Phosphorus in Low P Acid Soils
The effect of agropastoral systems replacing native savanna on microbially bound phosphorus (Pmic) in low P acid soils was investigated. Chloroform released P (PChl) was measured to estimate Pmic. In a long-term improved pasture experiment, PChl was higher in grass-legume (GL) than grass-only pasture (GO). Although the P balance was slightly higher in GO than in GL, available P contents followed the same trend as PChl suggesting that the presence of legumes enhances the maintenance of P fertility. In a rice-pasture system, PChl was higher than under rice monocrop indicating an effect of the cropping system on PChl that goes beyond P inputs, and includes factors such as soil cultivation, herbicide application and organic matter input. Pmic may not be seen as a factor competing for plant available P in these strongly P-sorbing soils, but as a rapidly cycling pool that protects P from sorption. The results suggest that Pmic is an important indicator of P fertility on low P acid soils.
