Module 5: Soils as a Key Resource for Food Systems

Overview

Interactions Between Soil Nutrients, Nutrient Cycling, and Food Production Systems

Along with water, sunlight, and earth's atmosphere, the soil is one of the key resources underlying food production by humans. In terms of the coupled human-natural systems we use as a way to understand food systems, we can say that human systems organize landscapes and manage soils, along with agricultural biodiversity and other parts of natural systems, to produce food. Soils exert an influence on this coupled system because they vary in terms of properties such as depth and nutrient content, which alters their response to human management. Soils also have great importance as the site of many nutrient and carbon transformations within the biosphere. They are a storehouse of beneficial soil organic matter that benefits the earth system in many ways. Also, by understanding soils and the earth surface and ecological processes that occur there, human management is able to maintain and improve them, as well as overcome initial limitations or past degradation.

The purpose of this module is to give you as a learner a basic grounding in the nature of soils and soil nutrients. Module 5.1 provides the foundation for understanding soils, soil nutrients and their connection to food. We will also focus on ways that soils are vulnerable to degradation that impairs their role in food production. In module 5.2 we will deepen understanding of how soil management can protect soils in their role of supplying nutrients to crops and protecting other valuable resources such as surface water. To accomplish this we will focus on nitrogen (N) and phosphorus (P) as key nutrients for food production in module 5.2.

• Goals and Learning Objectives
• Assignments
• Module 5.1: Soil basics
• Module 5.2: Soil Nitrogen and Phosphorus: Human Management of Key Nutrients
• Summative Assessment
• Summary and Final Tasks