Water, soil and chemical losses: Field experiments and model analysis

The study of the environmental impact of water erosion, chemicals and nutri ent transport by runoff water is very important to protect soil and water q uality. It is possible to find much literature on this topic, but the surve y data lack uniformity and represent many different agronomic or natural en vironments. This is due to the wide range of parameters involved in these p henomena, such as soil and geomorphologic characteristics, tillage and crop management, nutrients and pesticides used Results of some experiments are presented in this paper. A comparison of wa ter, soil and chemical losses has been made between experimental data and m odeling outputs, both at plot and at watershed scale. The findings indicate that monitoring and modeling are two complementary instruments, both neces sary for the analysis of agrochemical transport phenomena, and that the pro posed methodology is useful to evaluate the related environmental impact un der different scenarios. (C) 1999 IAWQ Published by Elsevier Science Ltd. A ll rights reserved.