After reading this article you will learn about:- 1. Definition of Soil Health 2. Importance of Soil Function for Crop Production 3. Examples of the Economic Benefits of Maintaining and Improving Soil Health.
Definition of Soil Health:
Soil health is defined as the continued capacity of soil to function as a vital living system, by recognizing that it contains biological elements that are key to ecosystem function within land-use boundaries. These functions are able to sustain biological productivity of soil, maintain the quality of surrounding air and water environments, as well as promote plant, animal, and human health.
Importance of Soil Function for Crop Production:
Some important soil functions related to crop production include:
i. Infiltration and storage of water;
ii. Retention and cycling of nutrients;
iii. Pest and weed suppression;
iv. Detoxification of harmful chemicals;
v. Sequestering of carbon;
vi. Production of food and fibre.
When the soil is not functioning to its full capacity as a result of soil constraints then sustainable productivity and net farmer profits over the long term are jeopardized.
Examples of the Economic Benefits of Maintaining and Improving Soil Health:
i. Better plan growth and yield by compaction remediation;
ii. Reduced risk of yield loss and/or better field access during periods of environmental stress (e.g., heavy rain, drought, pest or disease outbreak);
iii. Reduced input costs by requiring less tillage;
iv. Reduced input costs by reducing fertilizer, pesticide, and herbicide requirements.
Soil health has recently captured the attention of farmers as soil degradation from intensive cultivation; mechanization, limited crop rotations, and lack of organic matter additions have reduced yield potential. This has often led to increased soil compaction, erosion, greater pest problems, and reduced crop productivity.
Often-stated problems include increased disease and pest pressure, soil compaction, decreased infiltration, reduced water holding capacity, low organic matter content, drought-prone soils, and excessive run-off and erosion. Though soil degradation was visible on many farms, a systematic approach to characterize soil health, which transcends the conventional soil nutrient analysis, was not yet available.
Soil health deals with both inherent and dynamic soil quality Fig 28.4. The former relates to the natural (genetic) characteristics of the soil (e.g., texture), which are the result of soil-forming factors. They are generally represented in soil surveys and generally cannot easily be amended.
On the other hand, the dynamic .soil quality component is readily affected by management practices and relates to the levels of compaction, biological functioning, root proliferation, etc.
The dynamic component is of most interest to growers because good management allows the soil to come to its full potential. The inherent and dynamic soil quality components do interact; however, as some soil types are much more susceptible to degradation and unforgiving of poor management than others.
At the heart of soil health is the integration of the soil physical, chemical and biological processes and functions Fig. 28.5. A healthy soil will be balanced for all three components.
In order to make interpretations of the health of a soil, the various processed and function in 28.6 need to be assessed through meaningful indicators. For years we have relied on inexpensive soil testing procedures to assess the chemical (fertility) properties, but methods for rapid assessment of the physical and biological status of the soil are not generally offered.
i. Identify the vital processes and functions of the soil needed for soil health assessment in relation to agronomic land use;
ii. Test different soil properties that can serve as potential soil quality indicators;
iii. Develop appropriate sampling and measurement protocols for soil health which can complement existing chemical laboratory and can be offered on fee for service basis;
iv. Develop criteria for interpreting soil health indicators in an agronomically meaningful way;
v. Develop and evaluate accessible databases as repositories for high quality, reliable soils information; and
vi. Recommend improved soil management practices based on soil health assessment that will ensure economic viability, environmental safety and social acceptability.