Download or read book Prediction and Measurement of Crop Water Requirements written by W. O. Pruitt and published by . This book was released on 1986 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Guidelines for Predicting Crop Water Requirements written by J. Doorenbos and published by . This book was released on 1975 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Calculation of crop evapotranspiration; Selection of crop coeficient; Calculation of field irrigation requirements.
Download or read book Guidelines for Predicting Crop Water Requirements written by J. Doorenbos and published by . This book was released on 1977 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication is intended to provide guidance in determining crop water requirements and their application in planning, design and operation of irrigation projects; Part I.1 presents suggested methods to derive crop water requirements. The use of four well-known methods for determining such requirements is defined to obtain reference crop evapotranspiration (ETo), which denotes the level of evapotranspiration for different set of climatic data. To derive the evapotranspiration for a specific crop, relationships between crop evapotranspiration (ETcrop) and reference crop evapotranspiration (ETo) are given in Part I.2 for different crops, stages of growth, length of growing season and prevailing climatic conditions. The effect of local conditions on crop water requirements is given in Part I.3; this includes local variation in climate, advection, soil water availability and agronomic and irrigation methods and practices. Calculation procedures are presented together with examples. A detailed discussion on selection and calibration of the presented methodologies together with the data sources is given in Appendix II. A computer programme on applying the different methods is given in Appendix III. Part II discusses the application of crop water requirements data in irrigation project planning, design and operation. Part II. 1 deals with deriving the field water balance, which in turn forms the basis for predicting seasonal and peak irrigation supplies for general planning purposes. Attention is given to irrigation efficiency and water requirements for cultural practices and leaching of salts. In Part II. 2 methods are presented to arrived at field and scheme supply schedules with emphasis towards the field water balance and field irrigation management. Criteria are given for operating the canal system using different methods of water delivery, and for subsequent design parameters of the system. Suggestions are made in Part II. 3 on refinement of field and project supply schedules once the project is in operation. The presented guidelines are based on measured data and experience obtained covering a wide range of conditions. Local practical, technical, social and economic considerations will, however, affect the planning criteria selected. Therefore caution and a critical attitude should still be taken when applying the presented methodology.
Download or read book Crop Evapotranspiration written by Food and Agriculture Organization of the United Nations and published by Fao. This book was released on 1998 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Equations, tables.
Download or read book Crop Water Requirements written by J. Doorenbos and published by . This book was released on 1975 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Guidelines for Predicting Crop Water Requirement written by FAO. and published by . This book was released on 1984 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Predicting Crop Water Requirements and Yield for Tomato Under a Humid Climate written by Naresh Kumar Arumugagounder Thangaraju and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Methodologies to predict crop water requirements in arid and semi-arid areas are well known. Humid areas pose a challenge, because irrigation is normally required only for short periods of a few weeks or months, during the peak of the summer growing season. The amount of irrigation water is also much less compared to the arid and semi-arid regions and is supplementary to rainfall. The objective of this study was to assess the usefulness of the AquaCrop (V 6.1) to estimate irrigation requirements for field grown tomato in a humid region of Eastern Canada. Input to the model was obtained from two years of field trials conducted at the Macdonald Farm of McGill University, Quebec, Canada. There were three irrigation treatments in 2017: 100%, 70 %, and 30 % of plant available water (AWC); and in 2019: 85 %, 60 % and 30 % of plant available water (AWC). The model was calibrated with the 2017 field results and validated with the 2019 field results. The calibrated and validated parameters were evapotranspiration, dry yield, total biomass and water productivity (kg of dry yield/m3 of water transpired). In the calibration phase, AquaCrop estimated dry yield and total biomass with a R2 of 0.94 and 0.86, respectively. For the validation phase, AquaCrop estimated dry yield and total biomass with a R2 of 0.84 and 0.96 respectively. The model overestimated biomass under water limiting conditions (30 % AWC) and underestimated the dry yield of tomato in general. There was no statistical difference in water productivity irrespective of the irrigation treatment. Overall, the model is suitable for predicting irrigation water requirement, crop yield, total biomass, and water productivity for tomato under humid climate. The validated AquaCrop model was then used to predict the irrigation water requirements and fruit yield for the once – in- 35-year dry year and the year of average growing season rainfall, for three different soil types (silty clay, sandy loam, heavy clay) under four irrigation regimes (90%, 75%, 65% and 50% of AWC). The irrigation water requirement for the once-in-35 dry year of 2001 under 90 % AWC was ~ 250 mm irrespective of the soil type and the observed water productivity was 2.32 Kg/m3. The year of average growing season rainfall (1993) with a total rainfall of 500 mm required ~ 165 mm under 90 % AWC with a water productivity of 2.38 Kg/m3. The sandy loam soil has the highest water productivity irrespective of the irrigation treatment for both the dry year of 2001 and the average year of 1993. Under water scarce conditions, 75 % AWC it could be used instead of 90 % AWC, with no significant decrease in crop yield and water productivity"--
Download or read book Crop water requirements written by Alain Perrier and published by . This book was released on 1985 with total page 960 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crop Water Requirements written by J. Doorenbos and published by . This book was released on 1992 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication is intended to provide guidance in determining crop water requirements and their application in planning, design and operation of irrigation projects; Part I.1 presents suggested methods to derive crop water requirements. The use of four well-known methods for determining such requirements is defined to obtain reference crop evapotranspiration (ETo), which denotes the level of evapotranspiration for different set of climatic data. To derive the evapotranspiration for a specific crop, relationships between crop evapotranspiration (ETcrop) and reference crop evapotranspiration (ETo) are given in Part I.2 for different crops, stages of growth, length of growing season and prevailing climatic conditions. The effect of local conditions on crop water requirements is given in Part I.3; this includes local variation in climate, advection, soil water availability and agronomic and irrigation methods and practices. Calculation procedures are presented together with examples. A detailed discussion on selection and calibration of the presented methodologies together with the data sources is given in Appendix II. A computer programme on applying the different methods is given in Appendix III. Part II discusses the application of crop water requirements data in irrigation project planning, design and operation. Part II. 1 deals with deriving the field water balance, which in turn forms the basis for predicting seasonal and peak irrigation supplies for general planning purposes. Attention is given to irrigation efficiency and water requirements for cultural practices and leaching of salts. In Part II. 2 methods are presented to arrived at field and scheme supply schedules with emphasis towards the field water balance and field irrigation management. Criteria are given for operating the canal system using different methods of water delivery, and for subsequent design parameters of the system. Suggestions are made in Part II. 3 on refinement of field and project supply schedules once the project is in operation. The presented guidelines are based on measured data and experience obtained covering a wide range of conditions. Local practical, technical, social and economic considerations will, however, affect the planning criteria selected. Therefore caution and a critical attitude should still be taken when applying the presented methodology.
Download or read book Evaporation Evapotranspiration and Irrigation Water Requirements written by American Society of Civil Engineers. Task Committee on Revision of Manual 70 and published by ASCE Press. This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: MOP 70 is a comprehensive reference to estimating the water quantities needed for irrigation of crops projects based upon the physics of evaporation and evapotranspiration (ET).
Download or read book Fundamentals of Irrigation and On farm Water Management Volume 1 written by Hossain Ali and published by Springer Science & Business Media. This book was released on 2010-09-08 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt: Agriculture is one of the few industries that has been creating resources conti- ously from nature. Sustainability of this industry is a crucial issue at now-a-days. Agricultural technologies are important to feed the growing world population. Agricultural engineering has been applying scienti?c principles for the optimal use of natural resources in agricultural production for the bene?t 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 climate uncertainty. I am happy to know that a book entitled "Fundamentals of Irrigation and On-farm Water Management", written by Engr. Dr. M. H. Ali, is going to be p- lished by Springer. The book is designed to cover the major ?elds of agricultural and environmental engineering such as weather, plant, soil, water, and basics of on-farm water management. The book will be quite useful for the students of agricultural engineering. Students of other related branches of engineering s- ences, and engineers working in the ?eld and at research institutes will also be beni?ted. The book may serve as a text book for the students and as a practical hand-book for the practitioners and researchers in the ?eld 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. Considering the topics covered, engineers, scientists, practitioners, and educators will ?nd this book as a valuable resource.
Download or read book Prediction of crop yields from quantity and salinity of irrigation water written by Water Resources Research Institute and published by . This book was released on 1969 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crop Ecology written by David J. Connor and published by Cambridge University Press. This book was released on 2011-04-28 with total page 575 pages. Available in PDF, EPUB and Kindle. Book excerpt: Food security and environmental conservation are two of the greatest challenges facing the world today. It is predicted that food production must increase by at least 70% before 2050 to support continued population growth, though the size of the world's agricultural area will remain essentially unchanged. This updated and thoroughly revised second edition provides in-depth coverage of the impact of environmental conditions and management on crops, resource requirements for productivity and effects on soil resources. The approach is explanatory and integrative, with a firm basis in environmental physics, soils, physiology and morphology. System concepts are explored in detail throughout the book, giving emphasis to quantitative approaches, management strategies and tactics employed by farmers, and associated environmental issues. Drawing on key examples and highlighting the role of science, technology and economic conditions in determining management strategies, this book is suitable for agriculturalists, ecologists and environmental scientists.
Download or read book Crop Ecology written by R. S. Loomis and published by Cambridge University Press. This book was released on 1992-10-08 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is centred on the 'production processes' of crops and pastures - photosynthesis and use of water and nutrients in fields. The book is unique in its combination of great breadth and depth in its treatment of production processes and systems problems. The approach is explanatory and integrative, with a firm basis in environmental physics, soils, physiology, and morphology, in contrast to descriptive or reductionist approaches. Systems concepts are introduced early and expanded as the book proceeds, giving emphasis to quantitative approaches, to management strategies and tactics employed by farmers, and to environmental issues. The systems approach is brought together in the final chapters where production and nutrient cycling are analyzed, for example farms and problems in an uncertain future are considered. The book is based on courses taught by the authors in Australia and the United States and is designed for use as a text for an introductory course in crop ecology (advanced undergraduates and beginning post-graduate level). It is more than a text, however. Given the wide range of subjects, the authors have integrated reference and background material to create a 'stand-alone' reference work useful to a wide audience of agriculturalists.
Download or read book Water and Crop Growth written by A.K. Kolay and published by Atlantic Publishers & Dist. This book was released on 2008 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: No crop can be grown without being adequately supplied with the requisite amount of water at the proper time. A thorough knowledge of the hydrological cycle, amount and distribution of rainfall, water resources and irrigation projects in India facilitates efficient utilization of water for crop production. Inadequate supply of water to crops in semi-arid and arid regions adversely affects agricultural production. Properties of water, the mode of its entry into the soil and its absorption by roots of crops are important for irrigation. This necessitates accurate determination of the soil moisture content, the plants and available water which is essential for growth and yield of crops. Its deficiency adversely affects their growth and yield. Irrigation must be extended to unirrigated areas in order to increase the production of food, fibre and fodder for which we must know the source of irrigation water, units and methods of measurement of water, methods of irrigating crop fields, factors affecting the choice of irrigation methods, the degree of the suitability of the available water for irrigating crops and the factors affecting the suitability of water for irrigation. As water is a relatively scarce commodity, we must know whether water of a little inferior quality can be utilized to irrigate crops. In addition, we must be familiar with the precautions which need to be taken in this regard. The accumulation of excess water in the soils of the crop fields affects the growth of crops adversely enough to reduce their yields. Choice of the method of land drainage varies with the variation in the topography of the land. It is also necessary to rectify the causes of waterlogging to bring the waterlogged land back under the plough to increase agricultural production. This necessitates drainage investigation and laying out of the proper drainage system. Water requirement of crops depends on the climate and the crop. More water is required to produce crops in the arid region than in the humid region. Crops like paddy and sugar cane require much larger amount of water than finger millet and pearl millet. The book extensively deals with all these aspects related to soil and crop production and suggests measures to enhance productivity through water conservation and proper management of water resources. It will be highly useful for the students, teachers and researchers working in this field. Besides, agriculturists and general readers will also find it useful and informative.
Download or read book Calibration of Crop Water Use with the Penman Equation Under United Arab Emirates Conditions written by Fareed H. A. N. Mohammed and published by . This book was released on 1988 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water shortage is one of the biggest problems facing agricultural development in the United Arab Emirates, because of the extremely arid climate and the large amount of irrigation water that is used for crops. Prediction of crop water requirements is essential to solve water management problems in this country. Two versions of the Penman equation, FAO and Wright, were used to estimate reference crop evapotranspiration from meteorological data for three regions in the U.A.E.; Northern, Central, and Eastern. Lysimeter measurements at the Northern region were provided for five crops; tomato for one season; cabbage, cucumber, and squash each for two seasons; and watermelon for three seasons. Crop evapotranspiration was estimated for these crops and related to measured crop evapotranspiration. It was found that there is great variation in measured crop evapotranspiration between seasons for individual crops, due to technical problems with the lysimeter. Combined seasons were used to calibrate the Penman equation, and the results indicated that the calibration improved the estimated crop evapotranspiration. Calibration coefficients for individual crops and for individual methods were calculated. Reference crop evapotranspiration (Etr) value for the three regions were correlated. A high correlation of estimated Etr among the three regions was found. Coefficients were developed to predict Etr at the Central and Eastern regions from the Etr at the Northern region.
Download or read book Crop Water Requirements Imperial Valley written by David Inouye and published by . This book was released on 1981 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:
