Developing Pedotransfer Functions and Spatial Estimates of Growing Season Nitrogen Mineralization to Inform Improved Nitrogen Management Strategies in Prince Edward Island

Abstract

Decision support tools (DSTs) and a framework for incorporating estimates of growing season nitrogen (N) mineralization (GSN) in soil, using analysis of total soil N (TN) to quantify the stable N pool, and biological nitrogen availability (BNA) to quantify the labile N pool in a zero- plus first-order kinetic function, were developed to inform N fertilizer recommendations. Overall, DSTs for biological processes as related to soil N dynamics were achieved using pedotransfer functions (PTF), digital soil mapping (DSM) and machine learning. From these results, a tiered approach to N fertilizer management was proposed. The DSM, as tier 1, provides estimates of GSN to producers who do not have point data; the PTF, as tier 2, is applied for producers who have surrogate data; and subsequent tiers are for producers with direct measures for N response variables.