Levels of Plant Available Phosphorus in Agricultural Soils in the Lake Erie Drainage Basin


Book Description

Phosphorus has been identified as the nutrient element most limiting to the growth of algae in Lake Erie. In addition, nutrient loadings by tributaries are a major source of phosphorus to the lake; of this load, the diffuse load, and especially the agricultural diffuse load is a major component of the total P input to Lake Erie. The particulate P load carried by a stream has several sources: native soil P, P from fertilizer, manure, and waste, P from crop residues and detritus. The bulk of sediment-P, however, is native soil P except where additions of manure have been heavy over many years. In light of these issues, a study was initiated to investigate levels of available-P in agricultural soils in the Lake Erie drainage basin. This report is concerned with two major objectives: (1) To survey actual field levels of available P in a county in Ohio and compare these with published soil test summary data for the same area; and (2) to determine if similar data were available in other Lake Erie Basin states and to determine if soil test methods and recommendations varied significantly from state to state. (Author).










Fertilizer Abstracts


Book Description










Sustainable Agricultural Systems


Book Description

A unique look at how the adoption of sustainable farming methods is being pursued throughout the world. This comprehensive book provides clear insight into research and education needs and the many points of view that come to bear on the issue of sustainability. Essential for agricultural leaders in research, education, conservation, policy making, and anyone else interested in creating an economically and environmentally sustainable agriculture worldwide.




The Effects of Reduced Tillage on Phosphate Transport from Agricultural Land


Book Description

This report examines and summarizes published and some unpublished data on the relative effects of conservation tillage (primarily no till) versus conventional tillage on surface runoff, soil loss and phosphorus loss. The data show that conservation tillage increased runoff relative to conventional tillage on soils with poor internal drainage and reduced runoff on more permeable soils. Conservation tillage greatly reduced soil loss and total particulate P (TPP) loss, but the percent reduction of TPP was only 89% of the percent reduction in soil loss. Conservation tillage increased soluble P (OP) losses in all cases. Conservation tillage was less effective in reducing plant-available (Bray P1) phosphate than in reducing TPP. P fertilization in excess of crop needs increased soluble P losses in runoff, and the effect of P fertilization on soluble P losses was greatest with no till because of P accumulation at the surface. (Author).