alexa Relationships Between Soil Test Phosphorus, Soluble Phosphorus, and Phosphorus Saturation in Delaware Soils
Agri and Aquaculture

Agri and Aquaculture

Journal of Fertilizers & Pesticides

Author(s): Maria C Pautler, J Thomas Sims

Abstract Share this page

Methods to identify agricultural soils that contribute to nonpoint-source pollution of surface waters by P are of increasing importance, particularly in areas with high animal densities (animal units per hectare of cropland). Our objective was to determine the relationship between agronomic soil test P (STP = Mehlich 1) and other soil P tests proposed to measure the potential for P loss by erosion, runoff, and leaching. We compared STP with soluble P, P in the “fast desorbing pool” (strip P), and soil P saturation for 127 soils (122 from Delaware and five from the Netherlands). Soil test P was significantly correlated with total P ( r = 0.57***, significant at the 0.001 level ), soluble P ( r = 0.71*** ), strip P ( r = 0.84*** ), and oxalate-extractable P ( P ox ; r = 0.84*** ) Strip P was a better predictor of soluble P than STP (r2 = 0.76*** ) The ratio of strip P/Pox (the percentage of reversibly sorbed P in the fast desorbing pool) increased as P sorption capacity, estimated from oxalate-extractable Al and Fe (Alox + Feox), decreased. We also determined the degree of P saturation (DPS) using three methods: Langmuir P sorption isotherms; oxalate extractions of P, Al, and Fe; and STP plus a single-point P sorption index (PSI). Soluble P, STP, and desorbable P increased for DPS values >30%, similar to upper DPS limits in the Netherlands and Belgium. Soils rated agronomically excessive in STP (>50 mg kg−1) had higher ratios of soluble P, strip P, and Pox to total P than those in agronomically optimum or lower categories.

This article was published in Soil Science Society of America Journal and referenced in Journal of Fertilizers & Pesticides

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version