THE KEY TO MANAGEMENT OF SOIL – PLANT – WATER RELATIONSHIP
Soil is the voluminous upper part of the earth crust that consists
of unconsolidated inorganic particles and organic fragments with pore
spaces between and within them. Pore spaces contain soil air, and
soil solution. In other words, soil volume consists of solid, liquid
and gaseous phases.
It is inside the pores that soil-plant-water relate physically, chemically and biologically and provide a dynamic open system for the growth of land plants.
During a heavy rainfall or over irrigation, water fills the pore spaces above the capacity of the pores. Water runs out of the pores
and turns into runoff. Soil particles get washed and take plant nutrients away. This super-saturation causes oxygen to become rare to the
roots. The normal soil-water-plant relationship alters and in its place an inhospitable environment for plants now exists while the stability of the soil has been compromised and water becomes a potential destructive force.
Quantity of pores, their shapes and magnitudes depend on the geometrical and mineralogical properties of the surrounding inorganic soil separates, their extent and their physical arrangements, or simply their textural classification and structure. A variation in soil texture creates changes in the sizes of pores, their mineralogical constituents and their chemical activities. Adequate knowledge of soil texture can contribute to
the proper management of soil-plant-water relationship and consequently
an efficient irrigation system while avoiding the hazards of erosion.