In a world where feeding an ever growing population is essential at the same time crucial, plant growth and the many elements that affect its efficient and effective maturations has become a growing concern as well. Soil is an important environment where most agricultural crops are grown and its salinity has been observed to be an important consideration in agricultural studies. Unfortunately, much of human intervention in using resource such as soil and water have made soils filled with extra toxic elements rendering it soil that cannot support agriculture.
The more salty the soil, the more difficult it is to grow crops and soil that has high salt content cannot be revitalized. Salt acquired by soil can be acquired by the soil through fertilizer dispersal but another way on how the salt gets into the soil is through water such as in irrigation. Acid rain bringing extra toxic substance to the soil is also a way on how salt enter the soil and imbibed by the plant through processes such as capillary action or osmosis.
“Osmosis displays itself in most biological systems that are cellular. The cell membrane is a semi-permeable membrane. So is the cell nuclear membrane which keeps DNA molecules inside the nucleus while allowing the transfer RNA molecules to pass through in and out of the nucleus. ” (http://members. aol. com/profchm/osmotic. html) Different plants need varying amount of salt in their soil. However, there are toxic levels for some other plants.
Salt water will affect plants because it penetrates the soil and imbibed by the plant eventually affecting its growth potential. “When salt dissolves in water, sodium and chloride ions separate and may then harm the plants. Chloride ions are readily absorbed by the roots, transported to the leaves, and accumulate there to toxic levels. It is these toxic levels that cause the characteristic marginal leaf scorch. ” (Perry, 2006) “Salinity is the concentration of dissolved minerals salts present in waters and soils on a unit volume or weight basis.
The major solutes comprising dissolved mineral salts are the cations sodium (Na), calcium (Ca), magnesium (Mg) and potassium (K), and the anions chloride (Cl), sulfate (SO4), bicarbonate (HCO3), carbonate (CO3), and nitrate (NO3). Salinity is expressed in a number of ways: mol/l (equivalents per liter), mg/l (ppm), electrical conductivity EC (dS/m or mmhos/cm) and total dissolved solids (TDS, %). ” (Majerus, 1996) Salts affect plant growth through salt salinity.
As salt enters the plant through physical and chemical means, it also alters the plants’ physical and chemical structures. Plants’ cell wall needs to maintain a level of salinity. When the level of salinity is abnormal, cell walls collapse thereby rendering the growth of the plant in danger. It is the objective of this paper investigation to know how salt affects plant growth. Objectives: To find out the effects of salt on plant growth. Hypothesis: Abnormal quantities of salt on soil may cause death of plants.