Aims and objectives

Content

The lecture course opens with a consideration of soil physical and chemical processes. It then goes on to describe their implications for soil management and plant growth.

Soil constituents and physical properties covered include particle size distribution; organisation of soil particles and creation of pore space; variations in soil texture, structure and their effects on aeration/water supply; processes leading to the development of structure in soils; soil water content, conductivity and moisture potentials; temperature and heat fluxes in soils. The soil nutrient and fertility section covers soil acidity and liming; major nutrient cycles, the assessment of nutrient availability; principles of using manures and fertilisers; nutrient losses and their environmental impact.

Soil management practices described include drainage problems and their alleviation; irrigation need and practice; cultivation and its effect on soils; compaction, erosion and soil degradation problems.

The course finishes with a consideration of soil-climate interactions as they affect agricultural systems. Included in this section is a discussion of classification systems for various land use and pollution control purposes.

Practical classes provide experience across the themes covered in lectures. Field visits demonstrate soil variation and its implications for land use/vegetation. Laboratory sessions include assessments of basic soil constituents (texture, moisture, organic matter and pH) for samples taken from the field visit sites. Computer workshops use an N-cycle model to provide data on flows of nitrogen for different agricultural management and soils.

Learning outcomes

• be aware of the basic soil components and how they vary
• explain how these components interact in determining practical soil characteristics and plant response
• explain the scientific basis of common soil management practices and how they affect soil quality.

Reading Lists