RUNOFF, INFILTRATION AND SUBSURFACE FLOW OF WATER IN ARID AND SEMI-ARID REGIONS

Transcription

1 RUNOFF, INFILTRATION AND SUBSURFACE FLOW OF WATER IN ARID AND SEMI-ARID REGIONS

2 Water Science and Technology Library VOLUME 21 Editor-in-Chief V. P. Singh, Louisiana State University, Baton Rouge, U.S.A. Editorial Advisory Board M. Anderson, Bristol, U.K. L. Bengtsson, Lund, Sweden A. O. Bobba, Burlington, Ontario, Canada S. Chandra, New Delhi, India M. Fiorentino, Potenza, Italy W. H. Hager, Zurich, Switzerland N. Hannancioglu, Izmir, Turkey A. R. Rao, West Lafayette, Indiana, U.S.A. M. M. Sherif, Giza, Egypt Shan Xu Wang, Wuhan, Hubei, P.R. China D. Stephenson, Johannesburg, South Africa The titles published in this series are listed at the end of this volume.

3 RUNOFF, INFILTRATION AND SUBSURFACE FLOW OF WATER IN ARID AND SEMI-ARID REGIONS edited by ARIE S. ISSAR Ben-Gurian University of the Negev, The Jacob Blaustein Institute for Desert Research, Sede Boqer Campus, Israel and SOL D. RESNICK University of Arizona, Tucson, Arizona, U.SA. SPRINGER-SCIENCE+BUSINESS MEDIA, B.Y.

4 Library of Congress Cataloging-in-Publication Data Runoff, inflltrat l on, and subsurface flow of water in arid and sem l -arid regians 1 edited by Arie S. Issar, Sol D. Resnick. p. cm. -- <Hater sclence and techno logy library v. 21) ISBN ISBN (ebook) DOI / Runaff- -Arid regi ans. 2. Gr ou ndwater flow--arid reglons. I. Issar, A. II. Resnlck, So l D. III. Serles. GB980.R dc ISBN Typeset by Wordbyte, POB 3102, Beer-Sheva, Israel Printed on acid-free paper Al! Rights Reserved 1996 Springer Science+Business Media Dordrecht Originally published by Kluwer Academic Publishers in 1996 No part of the material protected by this copyright notice may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage and retrieval system, without written permission from the copyright owner.

5 TABLE OF CONTENTS PREFACE vii HYDROLOGIC BALANCE STUDIES OF SEMI-ARID AND ARID WATERSHEDS (Sonoita Creek, Arizona and Negev, Israel), Measurements, Concepts, and Case Histories S.D. Resnick, J. Ben-Asher, A. Dody and M.H. Diskin Introduction Case History: Sonoita Creek Watershed Case History: The Avedat Watershed RUNOFF AND EROSION CONTROL IN ISRAEL M. Agassi, Y. Benyamini, J. Morin, S. Marish and E. Henkin Introduction Study of Rainfall Patterns '" Effect of Some Physical Properties of the Soil on Infiltration Rates Effect of Some Chemical Properties of the Soil on Water Intake Description of Land at Experimental Sites Soil and Water Conservation by Soil Tillage Management Phosphogypsum as an Amendment for Runoff and Erosion Control in Semi-Arid Regions of Israel Results and Conclusion QUANTITATIVE PREDICTION OF RUNOFF EVENTS IN THE NEGEV DESERT A. Ben-Zvi Introduction Hydrologic Process in the Negev Runoff Management Purposes The Data The Model Application Summary SOIL SEALING, INFILTRATION AND RUNOFF Y. Mualem and S. Assouline Introduction Crust Characteristics: Observations and Concepts A Conceptual Model of Soil Crusts: The Exponential Model Effect of Crusts on Flow Processes in Soil Dynamics of Soil Sealing Conclusions

6 PREFACE Arid and semi-arid regions can be defined as environments in which water is the limiting factor for bio-systems. This means that survival of life in these regions involves a constant struggle to obtain this limited commodity and draw the maximum benefit out of it. However, despite the difficulties for plants, animals, and man to live in, these regions, they are being utilized more and more because of the pressure of world population growth. This is expressed in the expansion of agricultural activities in desert lands as well as by the formation and rapid growth of urban and industrial centers. These trends result in a growing demand for water on the one hand, and the disposal of vast amounts of waste water, as well as other types of refuse, on the other. Meeting the first demand, namely, supplying water to the agricultural communities and urban centers, involves, in many instances, the over-exploitation and misuse of natural water resources. The surplus of waste water, sometimes highly loaded with toxic compounds, is likely to cause irreversible damage to the environment. The geoscientists and engineers face a challenge on two conflicting fronts. Success on one front, namely, in answering the full demand for water, may lead to an increase in the pollution of the environment by waste water. The question is whether a way exists by which demand can be supplied and negative processes avoided, mitigated, or even reversed to become positive? Although no direct answer to this dilemma is given in the present volume, a contribution is offered towards its solution by illuminating different aspects of the hydrological cycle. This is offered as a tool for gaining a comprehensive understanding of the environment (and its response to man's intervention) as a dynamic system. With respect to water resources, this understanding includes comprehension of the processes through which the waters go, and processes which they initiate, from their condensation to precipitation, their arrival at the surface of the earth, runoff, infiltration, storage and their flow in the subsurface systems. The latter comprise the elements which are left in the soil or which are flushed back into the hydrological cycle. To gain a comprehensive approach requires understanding the hydrological cycle in a holistic way. The conventional approach grasps the system of water flow on earth as solely designed for man's use, and thus plans how it should fulfill his needs alone. After exploitation, he disposes of what remains, as waste water, dumping it into rivers or lakes, which become open sewers, or permitting it to seep back into the subsurface to contaminate the groundwater. These solutions quickly backfire and even the water bodies which were a source of supply become contaminated. Adopting a holistic approach involves two parallel courses in research policy. First, research projects should aim at understanding the hydrological system as a whole, and second, the particular components of the system have to be understood in detail. In arid countries this entails great difficulty, because hydrological information in these regions vii

7 viii Preface is characteristically scarce. This is a result of the random nature of the rain events and the sparseness of the population. This book tries to cope with these problems by adopting a holistic approach rather than restricting itself to a particular section of the hydrological cycle. It includes reports on recent studies which have led to a better understanding of a variety of problems prevailing in semi-arid and arid zones. Emphasis has been put on studies which incorporate the use of advanced applied techniques developed for dealing with these water problems. This has been done with the hope of providing guidance for solving special problems of water supply and safe reuse of wastes, liable to arise during future development in these zones. Chapter 1 deals first with a complete water-balance study for a semi-arid watershed in southern Arizona, USA; then the rainfall-runoff relationship is analyzed by using a relatively new parametric cell model for an arid watershed in the Avedat area, Israel. The Chapter also briefly describes water conservation and augmentation methods under study and some methods used in semi-arid and arid zones, namely: water harvesting, which dates back to the ancient Nabatean farms in the Negev highlands; evaporation suppression; seepage control; reuse of treated sewage effluents; importing water; cloud seeding; and desalination. Chapter 2 deals with soil sealing, runoff and erosion control; the authors used a field rainfall assimilator in their studies. Positive research results are presented for reducing soil crusting by chemical means, and controlling soil erosion by using a basin tillage system. In Chapter 3, the quantitative prediction of runoff events in the Negev Desert is discussed. This is obtained by constructing an event base model aimed at the description of the magnitude and frequency of the events. In Chapter 4, the effects of soil crust on infiltration and runoff in desert areas due to the characteristic short, intense stolms as viewed by different researchers are discussed by the authors and compared to their own research findings. Professor Resnick's sabbatical in Israel was funded by the Jacob Blaustein International Center. This support is gratefully acknowledged. We would like to thank Engineer Morel Wolf for his help with the graphics, Mrs. Sally Alkon for typing and Mrs. Beverly Katz for editing the English. A.S. Issar Sede Boqer, Israel S.D. Resnick Tucson, Arizona, USA