Aspects of the fertility of agricultural soils

Abstract

This application for the award of degree of Doctor of Science for work on aspects of soil fertility is divided, for convenience, into six interrelated parts. A summary of the work in each part is presented below together with a list of references cited. Copies of each of the cited papers follow. These are divided into the six parts and follow the same order as that in the lists of references: Part 1. Lime - phosphorus interactions in acid soils, Part 2. Aspects of nitrogen cycling in the plant-soil system, Part 3. Soil acidification and micronutrient availability, Part 4. Role of grazing animals in pastoral soil fertility, Part 5. Soil organic matter quality, soil biological activity and soil aggregation in agricultural soils, Part 6. Mineral nitrogen in the plant system.