Page 36 - Enzymes in Tropical Soils

24 Enzymes In Tropical Soils

During the reaction, the organic P is hydrolized to produce alcohol and
orthophosphate ions. The organic P is not available, while the orthophosphates are
easily available for plant root absorption. As has been well understood, only
inorganic ions dissolved in soil water like orthophosphates are easily absorbed by
plant roots. Therefore, the presence of soil enzymes is of great importance to
speed up the cycling of particular plant nutrients such as C, N, P, and S so that
these nutrient elements are available to plants. Through this cycling, considerable
amounts of plant nutrients packed in organic matters may be recycled in the soil-
plant system.
The changes of unavailable forms of nutrients to those available to plants
may solve the problem of nutrient leaks from the soil system as long as organic
matters are returned to the soil system. The presence of soil enzymes may then
sustain the productivity of soils with minimum or lower external nutrient inputs,
particularly in fertile soils. Therefore, the management of soil enzymes and their
activities and producers in soils is very important. The success in the ultilization of
enzymes in nutrient management may lower the budget for input fertilizers.

3.1 Soil – Plant – Animal – Human Relationship

Men were created out of soils. This statement is written in the holy book of
Quran. Modern scientific facts support completely this statement. Soils are the
storage of constituents called nutrient elements absorbed and used by plants to
pack the sun energy in the forms of various organic substances such as sugars,
proteins, and fats. These substances are then consumed by animals and humans to
grow and develop. Therefore, the elements found in animals and human tissues
are similar to those found in soils. A complete relationship between the soil,
plants, animals, and humans is described in Fig. 3.1.
As described in Fig. 3.1 and also previously in Fig 1.1, available nutrients in
soils are internally buffered by the chemical reactions involving soil primary
minerals through weathering proceses as well as soil secondary minerals and
organic matters through adsorption/desorption and precipitation/dissolution
processes. Organic matters also supply nutrient elements through
decay/decomposition processes. The soluble available nutrients in soils are also
supplied by external sources such as atmospheric deposition, irrigation, and in
many cases, fertilization.

Abdul Kadir Salam - 2014