Soils and Food Production: Feeding the World

Soil morphology, genesis and classification food production

In last month’s Soil Science Online Blog, we discussed soil science’s impact on the world around us. Soil science affects a lot more industries than many realize, with one of the most important industries being food production.

How soil science affects food production

The vast majority of the food we eat and fiber we wear comes from the soil, with many factors affecting the overall productivity of the agricultural system. Weather is one factor. Without the proper climate, crops can fail due to drought, floods, extreme heat and extreme cold. A farmer’s skill is another factor. A well-educated agricultural community benefits everyone because the best farmers know how to maximize field productivity while simultaneously protecting the environment. A third, critical factor is the soil in which the plants grow. Not all soils are created equal, and not all soils are suited for agricultural production.

Plants need to have the right soil to properly grow. Plants live on a liquid diet. Water taken in by the roots transport vital nutrients that are necessary for the completion of a plant’s life cycle. Once inside the plant, that water inflates the plant cells and provides the structural support that keeps the leaves facing the sun, the ultimate source of energy. Sandy soils drain fast and do not hold much water. Soils with high clay contents don’t always drain well. The ideal soil holds enough moisture for the plant to thrive but not so much water that the plant drowns. Like people, plants are aerobic organisms. When soils are saturated (poorly drained), oxygen is limited, and plants become stressed.

Plant’s requirements

Plants require seventeen essential elements to complete their life cycle: carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, boron, chlorine, copper, iron, manganese, molybdenum, nickel and zinc. Of the seventeen, The soil supplies fourteen of the seventeen elements. Plants need essential nutrients in varying amounts. Just like humans, plants also require a balanced diet. Removing any one of the seventeen nutrients from plant’s diet disrupts its life cycle, potentially killing the plant.

In deep soil profiles, plants can have large root systems that exploit a large volume of soil, gaining access to more water and essential nutrients. Plants with shallow root systems are the first to show symptoms of drought and growth-limiting nutrient deficiencies. Poor management can result in erosion of the vital topsoil, leaving behind the much less fertile subsoil. Improper tillage can lead to compaction, which restricts root growth.

Role of soil scientists

It is the role of soil scientists to understand the complex relationships between the soil and plant to help make food production more sustainable. Techniques and technology have been developed with this purpose for centuries, with methods such as crop rotation, irrigation, plant breeding and fertilization being continually researched and developed with two goals in mind: maximize the production of food while simultaneously minimizing any negative impacts on the environment.

The future of soil and food production

Different ideas about the future of soil and food production exist. Of course, developments in hydroponics, or the growing of crops without soil, vertical farming and greenhouses exist, but many argue solutions exclusive of the vast amount of available land and resources should not be pursued. More sustainable practices and better soil management are necessary for the lasting availability of food to feed the growing population of the world. Because of this determination to find the most sustainable solutions in soil conservation and crop production, the need for soil scientists is strong.

It’s difficult to say what will happen if we fail to care for the earth’s soil, a natural resource that should be considered as important as water we drink and air we breathe. Without good soil and those who care about it, crops will fail, erosion will continue and the world’s hunger problem will only grow.

Each month we will be discussing a different topic within soil science. Check the blog frequently to find answers to common questions about soil and to learn more about this fascinating field.