Soil pH: A study Carried Out in Two Villages of Mao

As a home gardener or an organic grower, it is important to know the soil pH because many plants have specific pH requirements, resulting in poor growth if the soil pH is not within a particular range. Soil pH is a measure of the acidity or basicity of soil. This is one key characteristic that can be used to make informed analyses regarding soil characteristics and know what type of plant can thrive in a particular region. The pH scale goes from 0 to 14 with pH 7 as the neutral point. Any pH reading below 7 is acidic and any pH above 7 is alkaline. The study of pH is important because it helps us to understand the availability of essential nutrients. Most horticultural crops grow satisfactorily in soils having a pH between 6 (slightly acidic) and 7.5 (slightly alkaline). When the pH is greater than 9, the soils are considered highly alkaline and are often found associated with toxic amounts of bicarbonate, carbonate, aluminium, iron etc. The acidity of the soil is mainly caused by a loss of organic matter, removal of soil minerals (when crops are harvested), erosion of the surface layer and effects of Nitrogen and Sulphur fertilizers.

 Using Nitrogen fertilizers containing ammonium-N undergo nitrification, resulting in soil acidity. As the percentage of ammonium increases in the given fertilizer, the acidifying potential will also increase and consequently leads to a reduction of the soil pH.  When soil pH is too low (acidic) or too high (basic), the intake of absorbing nutrients from their roots is lesser. These resultant nutrient deficiencies cause problems including yellowing of the leaves, stunted growth, or the absence of flowers and fruits on plants.

For the study of soil samples, two different regions were selected (Song Song and Kalinamei in Mao). Fifteen soil samples were taken and the pH is recorded with the help of a pH strip. The different soil samples include

a.) Roadside soil (4 samples)

b.) Garden soil (4 samples)

c.) Clay soil (4 samples)

d.) Home soil (3 samples).

The study aims to correlate the plants found or the plants which can thrive in such soil. The sample (1 to 3 teaspoons) of soil was taken in a 500 ml beaker and then it is filled with distilled water to the same level as the soil sample. Then the mixture is stirred, shaken vigorously for a minute and let the sample rest for a minimum of 30 minutes before continuing. The pH test strip is dipped into the soil mixture and waited for the colour to change. The change in colour is observed and this is compared with the colour chart that comes with the strips. From the fifteen soil samples tested, it is found that all the samples have pH ranging between 6 and 7 which is considered neutral.

This value shows that it is the desirable pH range for optimum plant growth of many horticultural crops. This range also promotes the maximum availability of plant nutrients and the right soil pH is the key factor to growing a healthy garden. This value shows that the study area is rich in nutrients and minerals that can be adopted as organic gardens. The foundation for a garden filled with vigorous plants having rich, organic soil is the optimum pH for the plant to grow because if the soil pH tests higher or lower, plants exhibit improper growth, poor development and fruiting.

From the study, it can be concluded that the study area has nutrients rich soil, which can be tapped to grow important ideal horticultural plants such as Lettuce, Asparagus, beetroot, broccoli, walnut, carrot, lemon, celery and oregano because these plants thrive well in the pH ranging between 6-7. This method can positively boost the food production and livelihood support of the people.

A Kayikhra

Assistant Prof. (Chemistry Dept.) Asufii Christian Institute, Punanamei, Mao