More efficient use of water and improvements in soil health can lead to average crop yield increases of 79%.
Healthy soil is full of organisms that can turn waste and minerals into crucial nutrients (food) for plants. It is important for farming that the soil is kept healthy with enough access to water and organic material, in order to ensure that crop yields (the number of crops you are able to produce) can remain high.
There are many ways to help protect the health of the land and soil. Whilst some of these require a lot of financial support, others are simpler to put into use by single farmers.
INCREASING SOIL ORGANIC MATTER
As crops use up the nutrients and water found within healthy soil for growth, it is important that we keep adding more nutrients to the soil to prevent it from running out. The best way to do this is to mix organic matter (waste products such as manure or compost) into the soil. These contain minerals which can be broken down into a nutrient-rich mixture to aid plant growth.
Whilst manure can be found through the waste of livestock and other animals, compost can be made from other waste products of human use. These can include: dead plants, wood chips or other inedible food scraps.
KEEPING SOIL SURFACE VEGETATION
Plants and trees within areas of soil help to retain moisture in the ground to help protect soil from erosion. This helps to maintain a good environment for the organisms that help plants to break down nutrients for food.
More vegetation also lowers the amount that soil is disturbed. Disturbing the soil can expose organisms and plant roots that would die if left out of the soil for too long. Surface vegetation helps to make the ground surface more stable and reduces the disturbance caused by falling rain.
By keeping soil surface vegetation, we can also reduce the growth of weeds, which use up the nutrients in the soil for no benefit.
CROP ROTATION
Crop rotation is the process of growing different types of crops in the same area over several years. This is done so that the soil of farms is not used for only one set of nutrients. When a single type of crop is grown in the same place for many years, the soil runs out of certain types of these nutrients. In crop rotation, one crop that removes a certain nutrient from the soil is then replaced by another crop which could return that same nutrient to the soil.
An example of a successful crop rotation cycle is ‘maize-cotton-cowpea’. Maize is a grain crop, whilst cotton and cowpea are cash crops (grown to be sold). In successful crop rotation cycles, crops which return Nitrogen to the soil (such as: Cowpea, Soybeans, Groundnuts or Beans) should be planted the year before any grain crops (such as: Maize, Teff, Sorghum or Wheat). This helps to replace important nutrients such as nitrogen in soil to allow grain crops to grow well.
The use of crop rotation in Malawi has increased crop yields in some areas by as much as 58%. Such crop rotations help to reduce soil erosion and improve soil health and crop yield through better soil structure.
REDUCING EROSION
Whilst all these methods of increasing soil health will help to prevent soil erosion, see the links below for other ways to help reduce the impacts of erosion.
