Soil Pollutants and Plant Health

Objective:  To observe the effects of various pollutants on the health and growth of corn (Zea mays), string bean (Phaseolus vulgaris) and okra (Abelmoschus esculentus).

Introduction:

The ever-increasing pollution of the environment has been one of the greatest concerns for science and the general public over the last few decades. Soil Pollution can be described as the contamination of a soil ecosystem due to the addition (production) of substances detrimental to plant and animal species that are dependent on the soil. The pollution of soil can be caused by spills, bad waste disposal and agricultural practices. This may result in the degradation of the soil, contamination of underground water, and death or poisoning of rooted plants and other soil organisms such as bacteria, fungi and nematodes.

There are several ways by which the soil can become polluted. They can become polluted by human activity and to a lesser extent, by soil erosion. Human activity such as allowing salts to become dissolved in irrigation water, followed by evaporation, leaving salt residues rendering the soil unfertile. These eventually results in the formation of crust, reduce infiltration and also reduces the availability of water to the plants.

One of the most common ways by which man can pollute soil is by the improper disposal of industrial and municipal waste. This usually result in chemicals leeching form the soil, evolution of gases such as methane and sulfides and lastly, the effluents reaching the underground water and streams.

This experiment investigates the effect of sugar, bleach, powder detergent, pimento leaf, fertilizer, gas oil mixture, counter flour and disinfectant.

Corn (Zea may) is a member of the Poacea family and is one of the first crop to become domesticated. It is described as a cold intolerant crop and is therefore cultivated tropical areas. The nutrients in particularly potassium, phosphates, and nitrogen – the latter in the form of either nitrate or ammonium – are needed for corn growth and development Most of the dry weight of the plant consists of organic carbonaceous materials resulting from photosynthesis and subsequent processes. At least 12 nutrient elements must be taken up for the corn plant to grow and develop normally. An adequate supply of each nutrient at each stage is essential for optimum growth at all stages. The best soil for corn is a well-drained with a texture of silt loam or loam type. It should be a type of soil with a high moisture holding capacity, high amount of organic matter and be slightly acidic (pH 5.3 to 7.3). A rainfall of 200 to 1,500 mm is required in its growing period.