Page 180 - Enzymes in Tropical Soils

168 Enzymes In Tropical Soils

“And among His Signs (in this), that you see the earth barren; but when we send down water
(rain) to it, it is stirred to life and growth (of vegetations). Verily, He who gives it life, surely,
is Able to give life to the dead (on the Day of Resurrection). Indeed He is Able to do all
things.”
(Quran Fushshilat 41:39)

Chapter XII:

SUMMARY

12.1 Roles of Enzymes in The Soil Environment
12.2 Enzyme Degradation and Stimulation
12.3 Using Soil Propertiess to Manage Enzymatic Activities

I
t is clear from the previous chapters that enzymes exist in the soil system and
are of great importance not only in availing plant nutrient elements from
organic sources but also in accelerating the cycles of some nutrient elements
such as C, N, P, and S in the environment. It is also obvious that some elements
are not biologically available in the forms of organic residues but are then readily
available in the forms of inorganic elements as the results of organic matter
decomposition catalyzed by soil enzymes. Some environmental factors may
directly or indirectly affect the magnitude of enzyme activities, which determine
the rates of soil biochemical reactions. Among the most important factors are soil
organic matter and N contents, soil water contents, soil pH, soil temperature,
concentrations of particular elements such as orthophosphates, sulphates, and
heavy metals, as well as available O 2 .
The changes in the magnitude of these soil environmental factors may
degrade or stimulate the activities of soil enzymes. The relationship between these

Abdul Kadir Salam - 2014