Importance of Soil Testing and Soil Health Management

Dr Lydia Zimik *

Soil testing is the process of examining a soil sample to determine its nutrient content, composition, and other qualities such as acidity or pH level. A soil test can show nutritional deficiencies, probable toxicities from high fertility, and inhibitions caused by non-essential trace elements by measuring fertility, or the soil's estimated growth potential.

Regular soil testing can help farmers evaluate whether their current management is robbing them of future output and profit. Soil testing include collecting soil samples, preparing them for examination, conducting chemical and physical studies, interpreting the results, and recommending fertiliser for the crops.

Soil testing is a critical component of lucrative, efficient, and ecologically responsible agricultural systems that deliver a balanced fertility programme. The fundamental goal of the soil-testing programme is to provide farmers with a service that will help them utilise fertilisers more effectively and efficiently, as well as improve soil management methods, in order to increase agricultural productivity. High crop yields are impossible to achieve without using enough fertiliser to compensate for current shortages.

Soil testing is utilised in the agricultural and horticulture sectors to help with fertiliser composition and dose selection. Lab testing are more exact and frequently include cutting-edge technology. In addition, expert interpretation of data and recommendations are typically included in lab testing. The true connecting link between agronomic research and its practical application to farmers' fields is the soil test with the ensuing fertiliser suggestion.

Soil testing, on the other hand, is not a goal in and of itself. It's a tool for achieving a goal. Other effective management methods, such as correct tillage, efficient water management, healthy seed, and suitable plant protection measures, also contribute to strong crop yields. Soil testing is necessary and is the first step in achieving high yields and maximising the return on fertiliser investment.

Why We Need Soil Testing

Fertilizer levels and types required for the same crop differ from soil to soil, and even from field to field on the same soil. Using fertilisers without first assessing the soil is analogous to taking medicine without first contacting a doctor to determine what is required. Fertilizers have been shown to boost yields, and farmers are aware of this. But, in order to maximise profit, are they using the appropriate quantity of the right fertilisers at the right time and in the right place.

A farmer may be applying too much of one element, which isn't essential for plant development, and too little of another, which is the key issue limiting plant growth, without a soil test-based fertiliser recommendation. This not only suggests that fertilisers are being utilised inefficiently, but it also implies that crop yields may be harmed as a result of inappropriate fertiliser kinds, amounts, or application.

Soil Testing

A soil sample may be tested to identify its composition, nitrogen levels, and pH balance, among other things. Soil testing is normally done as part of a four-phased programme: Soil sampling, sample analysis, data interpretation, and soil management suggestions are all part of the process.

Although soils may be evaluated at any time of year, the fall is a particularly good time. Fields are normally drier and more accessible, and the laboratory is not as crowded as it is in the spring. When sampling, the soil should be dry enough to till. If you gather wet samples, they should be air-dried before being packaged and delivered.

Wet samples are more difficult to handle, are more likely to be lost in the mail, and cause significant delays in laboratory testing. Nitrate-nitrogen analysis cannot be performed on wet samples. Cropping intensities, soil types, fertiliser rates, tillage methods, meteorological conditions, and fresh research results all influence the frequency of soil sample.

1. Continuous Row Crops (conventional) - every two to three years.
2. Double-Cropping Systems - every two years.
3. Continuous No-Till Corn or Cotton - every two years.
4. High-Value Cash Crops (Vegetables) - annually.
5. Any time a nutrient problem is suspected.

The area for sampling the soil test findings are only as good as the sample taken. As a result, each soil sample supplied to the lab should be representative of the region where fertiliser recommendations will be issued. A composite sample, consisting of tiny bits of soil gathered from roughly 20 places, should be collected. Soil samples from 8 to 10 different areas should be gathered at random for lawns and gardens.

If the region can be fertilised independently, areas with contrasting soils, trouble locations, or sections of fields where crop response is markedly different should be sampled separately.

Collection of Soil Sample

1. Each field should be sampled independently. Divide the field and sample each section individually if the regions within it differ significantly in crop growth, soil appearance, or elevation, or are known to have been cropped, fertilised, and manured differently.

2. Take a sample of each region as a whole. Remove the surface litter first, then collect a small sample from the surface to plough depth from a variety of locations around the field (10 to 15 per acre). Take these samples and place them in a clean container.

3. Do not take a sample from an out-of-the-ordinary location. Avoid places that have just been fertilised, old bunds, and swampy regions, as well as areas near trees, compost piles, and other non-representative areas. To plough depth, take a consistent thick sample from the surface. With a spade or a trowel, dig a v-shaped hole, then cut a uniform thick slice of soil from the exposed soil face's bottom to top, collect the sample, and place it in the bucket.

4. Pour the dirt from the bucket onto a clean towel or piece of paper and carefully mix before discarding by quartering. Quarterly testing may be accomplished by mixing the sample thoroughly, splitting it into four equal parts, rejecting two opposing quarters, mixing the remaining two sections, dividing into four parts, rejecting two opposite quarters, and so on. Before packaging, the sample should be air dried in the shade for an hour or two.

5. Each cotton bag should be large enough to carry a 500 g soil sample and well labelled to allow for sample identification. For each sample, fill out the soil sample information page and include it with the soil sample. Send the samples to the Soil Testing Laboratory for analysis.

6. When you receive the soil test and fertiliser suggestion report from the soil testing laboratory, keep a note of the areas studied for future reference.

Soil micronutrient levels have decreased as a result of the use of high-yielding cultivars, intensive cropping, and reduced use of organics, as well as a shift to high-uses of NPK fertilisers. Soil fertility has a direct link with crop yields, given that all other factors are in excellent functioning condition.

As a result of a continuous cropping system without adequate fertiliser supplies, there is a good risk that significant nutrient shortfalls may develop over time. The physical properties of the soil, as well as the availability of nutrients, affect its productivity. Plants would not be able to use the nutrients in the soil unless the soil was in good structural condition.

Conclusion : Soil testing may be performed to determine and quantify the availability of key plant nutrients in the soil. Modern soil tests, on the other hand, are based on concepts and processes devised some decades ago, with little change in their overall approach.

To perform an appropriate soil test, one must first understand the physicochemical and biological characteristics of soil, as well as the activities that occur at the soil-root interface. This information will guide future soil and crop sustainability by solid prescriptive effective soil management techniques for nutrient availability through organic and inorganic fertiliser sources.