Page 24 - Enzymes in Tropical Soils

12 Enzymes In Tropical Soils

Chapter II (Theory of Enzymology) deals with some theoretical aspects of enzymes
related to activation energy and how enzymes work in accelerating the
decomposition of organic matters. Chapter III (Roles of Enzymes in Nutrient
Cycling) deals with the roles of soil enzymes in decaying processes of soil organic
matters and supplying plants with nutrients from organic sources and also roles of
enzymes in the cycling of some nutrient elements such as C, S, N, and P. Chapter IV
(Important Soil Enzymes) describes some of the important soil enzymes and their
roles in accelerating the decay rates of organic matters and the cycles of some
nutrients such as C, N, P, and S in the soil system.
Enzymatic activities are indeed of great importance and are affected by
several factors; discussed a little bit in Chapter IV, and specifically discussed in the
following chapters. Chapter V (Effects of Organic Matter on Soil Enzymes)
specifically discusses the influence of organic matters on the activities of soil
enzymes. Chapter VI (Effects of Soil Water and Temperature on Soil Enzymes)
specifically describes the influence of soil water content and temperature and how
to manipulate these properties by regulating soil water and soil temperature to
enhance soil enzymatic activities. Chapter VII (Effects of pH on Soil Enzymes) and
Chapter VIII (Effects of Nutrient Elements on Soil Enzymes) deal with the effects of
soil pH and some competitive elements, respectively, on soil enzymatic activities.
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While H ions may enhance or lower the activities of enzymes, some competitive
elements may inhibit the work of some soil enzymes. The effects of inhibiting
elements are demonstrated more clearly by the presence of heavy metals
discussed in Chapter IX (Effects of Heavy Metals on Soil Enzymes). Soil enzymatic
activities may also be degraded by forest clearing as discussed in Chapter X
(Enzyme Degradation by Forest Clearing in Lampung).
The presence of soil enzymes is of great importance. Because their
presence may accelerate the release of nutrient elements from organic sources,
part of the nutrients needed by plants may be substituted by the nutrients released
by organic sources. Chapter XI (Utilization of Soil Ennzymes) of this book deals with
the utilization of soil enzymes, particularly in agriculture. This book is closed by
Summary (Chapter XII) stressing the important roles of soil enzymes and their
prospective utilization in agriculture.

Important Questions

1. What are meaned by essential and non-essential elements for plants? Please give
some examples for the respective group of elements!

Abdul Kadir Salam - 2014