Page 6 - Ilmu Tanah Book

The Chemistry and Fertility of Soils under Tropical Weeds v
v

PREFACE

Weeds are distinct due to some of their characteristics in the soil environment. In
addition to the fact that they are destructive to crops, and therefore they are
undesirable in cultivated land, weeds are more importantly very competitive. Their
competitiveness is not only physically and biologically but also chemically.

A great deal of researches reveals that the presence of weeds modifies the
chemistry and fertility of soil environment. The chemistry and fertility of soils
affected by weeds may include soil reaction and other soil properties affected by
the changes in soil pH like the soil cation exchange capacity, the soil enzymatic
activities such as those of phosphatases, ureases, arylsulfatases, and -
glucosidases, the soil exchangeable potassium, the soil organic carbon, phosphorus,
nitrogen, and sulfur contents, and the heavy metal solubility. This book deals with
these kinds of soil chemical and fertility properties under various tropical weeds
mostly investigated in the Province of Lampung Indonesia.

Gratitude is extended to the institutions supporting each of the research: the
University of Lampung and the Japanese Society for the Promotion of Science, all
students participating in each research, and also my colleagues in the Department
of Soil Science the University of Lampung for their invaluable participation,
suggestion, and criticism. We hope this concise book may contribute something to
the fast growing science particularly in tropical agriculture.

Bandar Lampung, 6 June 2019
AKS/NS

Abdul Kadir Salam and Nanik Sriyani – 2019