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Practices of Irrigation & On-Farm Water Management: Volume 2 Practices of Irrigation & On-farm Water Management: Volume 2 M.H. Ali Practices of Irrigation & On-farm Water Management: Volume 2 Foreword by M.A. Salam 123 Dr. M.H. Ali Agricultural Engineering Division Bangladesh Institute of Nuclear Agriculture (BINA) Mymensingh 2202, BAU Campus Bangladesh [email protected] (URL: www.mhali.com) ISBN 978-1-4419-7636-9 DOI 10.1007/978-1-4419-7637-6 Springer New York Dordrecht Heidelberg London © Springer Science+Business Media, LLC 2011 All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, LLC, 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer soft-ware, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks, and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) Foreword Agricultural technologies are very important to feed the growing world population. Scientific principles of agricultural engineering have been applied for the optimal use of natural resources in agricultural production for the benefit of humankind. The role of agricultural engineering is increasing in the coming days at the forthcoming challenges of producing more food with less water, coupled with pollution hazard in the environment and climate uncertainty. Irrigation is continually straining our limited natural resources. Whether it is through salinity, waterlogging, sedimentation, nutrient transport, or excessive water consumption, irrigation has an impact on our natural ecosystems. It is therefore important that the irrigation system is properly designed, monitored, and executed not only for the benefit of the irrigator but also for the wider community. I am happy to know that a book (2nd volume in series) entitled “Practices of Irrigation and On-farm Water Management,” written by Engr. Dr. M. H. Ali, is going to be published by Springer. This book is designed to cover the major fields of applied agricultural engineering such as designing water conveyance systems, selecting and designing irrigation systems, land and watershed management, per- formance evaluation of irrigation systems, drainage system, water resources man- agement, management of salt-affected soils, pumps, renewable energy for irrigation, models and crop production functions in irrigation management, and GIS in irrigation management. This book will be quite useful for the students of agricultural engineering. Students of other related branches of engineering sciences, and engineers work- ing in the field and at research institutes, will also be benefited. The book may serve as a textbook for the students and as a practical handbook for the practitioners and researchers in the field of irrigation and on-farm water management. Utilization of the recent literature in the area and citation of relevant journals/reports have added a special value to this book. v vi Foreword I hope this textbook will be used worldwide to promote agricultural production and conservation of the most important natural resource, water. (Dr. M.A. Salam) Mymensingh, Bangladesh Director (Research) May, 2010 Bangladesh Institute of Nuclear Agriculture Preface Crop production depends on the successful implementation of the agricultural and water management technologies. This is vital to feed the growing world population. The implementation of technologies is also important to minimize environmental degradation resulting from agricultural activities. Agricultural and natural resources engineers are applying scientific principles for the optimal use of natural resources in agricultural production. Water is the scarcest resource. The importance of the judicious use of water in agricultural sector for sustaining agricultural growth and the retardation of environ- mental degradation needs no elaboration. Judicious use of water for crop production requires knowledge of water conveyance and application methods, their design- ing, strategic management of water resources, land and watershed management, etc. Increasing efficiency in conveyance and pumping systems are also of great concern. Irrigation management strategy practiced in normal soils may not be appropriate in problematic soils such as saline soils. This book covers all of the above aspects. In addition, the book covers some recent dimensions such as pollution from agri- cultural fields, modeling in irrigation and water management, application of the geographical information system (GIS) in irrigation and water management, and renewable energy resources for irrigation. Sample workout problems are provided to explain the design and application methodologies in practice. The comprehensive and compact presentation of this book will serve as a text- book for undergraduate students in Agricultural Engineering, Biological Systems Engineering, Bio-Science Engineering, Water Resource Engineering, and, Civil and Environmental Engineering. It will also be helpful for the students of relevant fields such as Agronomy, Biological Sciences, and Hydrology. Although the target audi- ence of this book is undergraduate students, postgraduate students will also be benefited from the book. It will also serve as a reference manual for field engineers, researchers, and extension workers in several fields such as agricultural engi- neering, agronomy, ecology, hydrology, civil, water resource, and environmental engineering. Effort was made to keep the language as simple as possible, keeping in mind the readers of different language origins. Throughout the book, the emphasis has been on general descriptions and principles of each topic, technical details, and modeling vii viii Preface aspects. However, the comprehensive journal references in each area should enable the reader to pursue further studies of special interest. In fact, the book covers broad interdisciplinary subjects. Mymensingh, Bangladesh Dr. M.H. Ali Acknowledgment I acknowledge the cooperation, suggestions, and encouragement of the faculty members of the Department of Irrigation and Water Management, Bangladesh Agricultural University. I would like to thank Engr. Dr. M. A. Ghani, former Director General of Bangladesh Agricultural Research Institute, and World Bank Country Representative, Bangladesh, who critically reviewed the content and structure of several chapters of the Book. I would also like to thank the scientists and staffs of Agricultural Engineering Division, Bangladesh Institute of Nuclear Agriculture, for their cooperation in various ways. Thanks are due to Dr. M. A. Salam, Director (Research), Bangladesh Institute of Nuclear Agriculture, for going through the book and writing few words about the same in the form of a “Foreword.” I am grateful to the authority of Soil Moisture Co. for supplying the pictures of their products and giving me permission to use the same in the book. My sincere thanks are also due to my affectionate wife Anjumanara Begham, daughter, Sanjida Afiate, and son, Irfan Sajid, for their support, understanding, and patience during the preparation of the manuscript. Mymensingh, Bangladesh Dr. M.H. Ali May, 2010 ix Contents 1 Water Conveyance Loss and Designing Conveyance System .... 1 1.1 Water Conveyance Loss . .................. 2 1.1.1 Definition of Seepage ................. 2 1.1.2 Factors Affecting Seepage . ............. 2 1.1.3 Expression of Seepage . ............. 3 1.1.4 Measurement of Seepage . ............. 4 1.1.5 Estimation of Average Conveyance Loss inaCommandArea................. 7 1.1.6 Reduction of Seepage . ............. 8 1.1.7 Lining for Reducing Seepage Loss . ........ 8 1.2 Designing Open Irrigation Channel . ............. 10 1.2.1 Irrigation Channel and Open Channel Flow . .... 10 1.2.2 Definition Sketch of an Open Channel Section . 10 1.2.3 Considerations in Channel Design . ........ 11 1.2.4 Calculation of Velocity of Flow in Open Channel . 12 1.2.5 Hydraulic Design of Open Irrigation Channel .... 14 1.2.6 Sample Examples on Irrigation Channel Design . 18 1.3 DesigningPipeforIrrigationWaterFlow............ 21 1.3.1 Fundamental Theories of Water Flow Through Pipe . .................. 21 1.3.2 Water Pressure – Static and Dynamic Head . .... 23 1.3.3 Hydraulic and Energy Grade Line for Pipe Flow . 25 1.3.4 Types of Flow in Pipe – Reynolds Number . .... 25 1.3.5 VelocityProfileofPipeFlow............. 26 1.3.6 HeadLossinPipeFlowandItsCalculation..... 26 1.3.7 DesigningPipeSizeforIrrigationWaterFlow.... 31 1.3.8 SampleWorkoutProblems.............. 32 RelevantJournals............................ 32 Questions................................. 33 References ................................ 34 2 Water Application Methods ...................... 35 2.1 General Perspectives of Water Application . ........ 36 2.2 Classification of Water Application Methods . ........ 36 xi xii Contents 2.3 Description of Common Methods of Irrigation . ........ 38 2.3.1 BorderIrrigation................... 38 2.3.2 BasinIrrigation.................... 40 2.3.3 FurrowIrrigation................... 43 2.3.4 SprinklerIrrigationSystems............. 46 2.3.5 Drip Irrigation . .................
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