Practical and Innovative Measures for the Control of Agricultural Phosphorus Losses to Water: An Overview

Abstract

Inputs of P are essential for profitable crop and livestock production. However, its export in watershed runoff can accelerate the eutrophication of receiving fresh waters. The specialization of crop and livestock farming has created regional imbalances in P inputs in feed and fertilizer and output in farm produce. In many areas, soil P exceeds crop needs and has enriched surface runoff with P. This paper provides a brief overview of P management strategies to maintain agricultural production and protect water quality that were discussed at the conference, “Practical and Innovative Measures for the Control of Agricultural Phosphorus Losses to Water,” sponsored by the Organization for Economic Cooperation and Development and held in Antrim, Northern Ireland, June 1998. The purpose of the conference was to assess current strategies for reducing the loads and concentrations of P from agricultural land to surface waters. Topics discussed at the interdisciplinary conference and reviewed here included sustainable P management in productive agriculture; assessing land application of P; evaluating and modeling P transport and transformations in soil, runoff, streams, and lakes; and implementation of integrated best management practices (BMPs). From these discussions, measures to control agricultural P transfer from soil to water may be brought about by optimizing fertilizer P use‐efficiency, refining animal feed rations, using feed additives to increase P absorption by the animal, moving manure from surplus to deficit areas, and targeting conservation practices, such as reduced tillage, buffer strips, and cover crops, to critical areas of P export from a watershed.

Effects of land use on phosphorus loss in the hilly area of the Loess Plateau, China

“…Some of the observed data of P concentration in runoff were over 0.1 mg/l, even 0.8 mg/l (Table 3). This meant, in the hilly area of loess plateau, current level of soil phosphorus could cause eutrophication of downstream water (Sharpley et al 2000). As the study site was in the subarea short of nitrogen and phosphorus (Jia et al 1994), controlling runoff from FR was helpful to abate the phosphorus pollution press of downstream water of Yellow river.…”

Effects of Long-Term Wastewater Application on Chemical Properties and Phosphorus Adsorption Capacity in Soils of a Wastewater Land Treatment System

“…The mechanical composition, soil water characteristics, bulk density, and hydraulic conductivity are remarkably similar among different samples taken from different fields of the same type of soil (12, 13). We tested variations of the concentrations of exchangeable Na, K, Mg, and Ca, Bray-1 P, and total organic carbon (TOC) in the top 60 cm soils sampled from fields 5,6,8,9,17,18,28,29, and 34. We found that each type of soil also has very similar chemical properties, even though they may be sampled from different fields, which allows use of only a few samples to obtain the information with negligible error.…”

Phosphorus efficiencies and responses of barley (Hordeum vulgare L.) to arbuscular mycorrhizal fungi grown in highly calcareous soil

“…However, the use efficiency of applied P is generally very low, ranging from 10% to 30% in the year applied (McLaughlin et al 1991). Continuous application of P fertilisers also increases the risk of P loss from soil to water, causing toxic algal blooms in water bodies (Sharpley et al 2000). Improving plant uptake of P from soil is an obvious alternative to the management of low P soils and the enhancement of use efficiency of P fertilisers.…”