Page 187 - Ilmu Tanah

174 The Chemistry and Fertility of Soils under Tropical Weeds

Glossary

Acidification To make a reaction medium to have a lower pH. For example, soil
acidification is to make the soil pH lower by using S powder or naturally by root
excretion of organic acids or by producing CO 2 during root respiration.

Adsorption A chemical process by which an ion is attached to a solid with an
opposite charge. For example, the adsorption of cations by the negative
charges of soil organic matters.

Alkalization To make a medium to have a higher pH. For example, soil alkalization
is to make the soil pH higher by a liming material such as calcite or dolomite.
In general it is referred to as liming.

Allelopathy Biochemicals produced by particular plant roots that are poisonous to
other plants.

Arylsulfatase An organic substance produced by microorganisms, earthworms, or
plant roots acting as a biocatalyst functioning to accelerate the detachment of
2-
S from organic S to form inorganic SO 4 available for plant root absorption.
Availability The easiness of soil nutrient elements of various forms in soils to be
absorbed by plant roots.

Abdul Kadir Salam and Nanik Sriyani – 2019