Preface

Choices for irrigation system development and management include a large range of technical, operational, economic, and social factors. Irrigation, as a complex socio-ecological system, deals with both the uncertainty of human-nature nexus dynamics and the interdependencies resulting from climate change. Irrigation systems have been under pressure to produce more with lower supplies of water. Globally, irrigation was by far the largest water consumer with between 90–94% of global water consumption. In addition, agriculture is the sector most affected by water scarcity, as it accounts for 70% of global freshwater use. Debates over irrigation system management in the Anthropocene have increasingly been framed in relation to social, economic, and environmental impacts and benefits, stimulating policy framework changes at different scales. In order to ensure irrigation system maintenance and development, technical innovation and social approaches should be understood and analyzed as complementary, as it happens in the water-energyfood nexus. This integrated approach addresses the different gaps by: (a) promoting water and food integrated approaches; (b) improving water efficiency and management at plot scale; (c) ensuring sustainable management of natural ecosystems; and (d) adapting irrigation systems to face water scarcity and environmental risks under climate change scenarios. This book, entitled *Irrigation – Water productivity and operation, sustainability and climate change*, aims to provide examples of consistent progress on mechanisms and approaches related to irrigation system challenges and gaps, such as water productivity, alternative water sources, environmental impacts, and climate change. This collection emphasizes the relevance of innovation and case study analysis to improve knowledge on some of the benefits and limitations of irrigation systems at different geographical contexts.

The first chapter, entitled "*Agronomic operation and maintenance of field irrigation systems*" presented by Luis A. Gurovich and Luis F. Riveros, starts from the consideration that field irrigation system projects are generally adequately designed and installed, considering soil, climate and crop characteristics, with theoretical high water application and distribution efficiencies. However, in most projects, the actual operation and maintenance strategies do not accurately include these characteristics, resulting in excessive water depths applied, generally exceeding crop water needs, unnecessary energy costs, as well as constraints on reaching potential crop yields and marketable crop quality. To address this gap, this chapter describes an approach to dynamic integration of soil hydrodynamic characteristics, potential evapotranspiration, and crop leaf area index evolution throughout the irrigation season, oriented to integrate smart water management strategies and techniques in the operation and maintenance of farm irrigation systems. In addition, this chapter presents how this dynamic integrative platform has been used by farming companies producing table grapes, wine grapes, and avocados in Perú and México. In line with this first chapter, Willians Riberiro Mendes, Fábio Meneghetti U. Araújo and Salah Er-Raki present the chapter "*Integrating remote sensing data into fuzzy control system for variable rate irrigation estimates*" to discuss the necessity of developing precise management zones to apply efficient variable rate irrigation technologies. The authors propose the use of an intelligent fuzzy inference system based on precision irrigation knowledge, for example, by creating perspective maps to control

the rotation speed of the central pivot. Results indicate that data from the edaphoclimatic variables, when well fitted to the fuzzy logic, can solve uncertainties and non-linear behavior of an irrigation system and establish a control model for high precision irrigation. A main benefit of this technology is that, because remote sensing provides quick measurements and easy access to crop information for large irrigation areas, images will be used as inputs. Furthermore, the ability of fuzzy systems to deal with complex systems can help farmers to make better decisions in agricultural processes.

Another mechanism to ensure operation and maintenance of irrigation systems was the search for new water sources (most of them conceived as un-conventional water resources) after most conventional water resources are overexploited or contaminated. An example of this commitment to new water sources can be found in the chapter presented by Hani Abdelghani Mansour in collaboration with Ren Hongjouan, Hu Jiandong, Bao Hong Feng, and Liang Changmei, and entitled "*Performance of water desalination and modern irrigation systems for improving water productivity*". This chapter provides a brief update of the Egyptian water strategy for developing irrigation systems. This strategy is based on the promotion of alternative water sources (such as saline water) and, furthermore, the development of varieties of some traditional crops that are saline resistant by using genetic engineering through which saline-tolerant genes are added to the plant. Through field experiments conducted in Saudi Arabia to analyze the effect of different drip irrigation systems and different saline water concentrations on wheat grain yield, water productivity and ecological effects of using saline water are discussed.

In addition to ensuring irrigation system management and water productivity, environmental risks and climate change issues are equally disruptive to the semi-arid and arid regions on a short and medium term. The chapter presented by Muhammad Irfan, Abdul Qadir, Habib Ali, Nadia Jamil, and Sajid Rashid Ahmad and entitled "*Vulnerability of environmental resources in Indus Basin after the development of irrigation system*" informs the reader about both questions. This chapter recognizes the climatic and topographic characteristics of the Indus Basin, which provides an excellent example for the development of an irrigation system. However, in the race of extensive water use, the environmental resources of the Indus Basin have been compromised after 150 years of developing irrigation systems through the construction of dams, barrages, and canals to divert the maximum river water for irrigation. Consequently, water quality was degraded due to the addition of fertilizers, pesticides, chemicals, municipal sewage, and industrial effluents. To overcome this gap, the authors claim that to ensure ecological requirements at water basin scale and to address natural risks, one must promote water governance through key stakeholders. In order to do that, a review of the Indus Water Treaty is promoted with the aim to meet the environmental issues of changing climate and rising water tensions between India and Pakistan.

Closing the book, the last chapter entitled "*Spate irrigation: Impact of climate change with specific reference to Pakistan*" and presented by Qudrat Ullah Khan and Obaid Ullah Sayal, describes the benefits and limitations of spate irrigation under the changing climate and how the promotion of storage dams could affect the hydrological system of the area and the irrigation practices. For example, the management of floodwater and perennial water has affected the water rights of the community and has changed the cropping pattern and land use, which was previously kept fallow and was now used for cultivation. Climate change can only exacerbate this situation. In fact, climate change has greatly influenced Pakistan

**V**

in frequent spells of extreme weather events, i.e. floods, glacial lake outbursts, droughts, and heat waves. These extreme events have made the country more vulnerable to climate change, as exemplified in the heavy flood of 2010 (causing

In addition, the growth of crops is highly affected by the amount of water and changes in temperature; according to an estimate by year 2040, with the increase in temperature of 0.5–2.5°C, the productivity of the crop will decline by 8–10%.

environmental issues affecting irrigation systems under a changing climate.

and experience as part of this publication.

The editors of this book want to thank to Anja Filipovic (as Commissioning Editor) and Marijana Francetic (Author Service Manager) for their kind support and invaluable guidance during the editing process. Our most sincere thanks go to those who have been interested in the book and to all authors who have shared their work

**Sandra Ricart, Antonio M. Rico and Jorge Olcina** 

University of Alicante,

Spain

The main challenge faced by irrigation systems is to produce enough food for a continued increase in population, although water and land competition, water quality standards, and water governance in a changing climate are still driving factors at the regional and global scale. This book covers subjects that are often found with both technical and social approaches, without mutual understanding of how irrigation systems should be perceived as socio-ecological systems. These types of contributions are mandatory in the Anthropocene context as a framework for promoting irrigation system management and governance from an agricultural and social sciences collaboration. Taking into account the background of the authors, this book is primarily addressed to the agricultural research community as it provides knowledge about the value of applying specific mechanisms of water productivity, management, and governance. Furthermore, this book should be useful for authorities and irrigators' communities and associations as a first step towards customizing their interventions at local and regional scales to address economic and

– mostly irrigated).

damage of approximately \$10 billion and flooding 38,600 km<sup>2</sup>

in frequent spells of extreme weather events, i.e. floods, glacial lake outbursts, droughts, and heat waves. These extreme events have made the country more vulnerable to climate change, as exemplified in the heavy flood of 2010 (causing damage of approximately \$10 billion and flooding 38,600 km<sup>2</sup> – mostly irrigated). In addition, the growth of crops is highly affected by the amount of water and changes in temperature; according to an estimate by year 2040, with the increase in temperature of 0.5–2.5°C, the productivity of the crop will decline by 8–10%.

The main challenge faced by irrigation systems is to produce enough food for a continued increase in population, although water and land competition, water quality standards, and water governance in a changing climate are still driving factors at the regional and global scale. This book covers subjects that are often found with both technical and social approaches, without mutual understanding of how irrigation systems should be perceived as socio-ecological systems. These types of contributions are mandatory in the Anthropocene context as a framework for promoting irrigation system management and governance from an agricultural and social sciences collaboration. Taking into account the background of the authors, this book is primarily addressed to the agricultural research community as it provides knowledge about the value of applying specific mechanisms of water productivity, management, and governance. Furthermore, this book should be useful for authorities and irrigators' communities and associations as a first step towards customizing their interventions at local and regional scales to address economic and environmental issues affecting irrigation systems under a changing climate.

The editors of this book want to thank to Anja Filipovic (as Commissioning Editor) and Marijana Francetic (Author Service Manager) for their kind support and invaluable guidance during the editing process. Our most sincere thanks go to those who have been interested in the book and to all authors who have shared their work and experience as part of this publication.

> **Sandra Ricart, Antonio M. Rico and Jorge Olcina**  University of Alicante, Spain

**IV**

the rotation speed of the central pivot. Results indicate that data from the edaphoclimatic variables, when well fitted to the fuzzy logic, can solve uncertainties and non-linear behavior of an irrigation system and establish a control model for high precision irrigation. A main benefit of this technology is that, because remote sensing provides quick measurements and easy access to crop information for large irrigation areas, images will be used as inputs. Furthermore, the ability of fuzzy systems to deal with complex systems can help farmers to make better decisions in

Another mechanism to ensure operation and maintenance of irrigation systems was the search for new water sources (most of them conceived as un-conventional water resources) after most conventional water resources are overexploited or contaminated. An example of this commitment to new water sources can be found in the chapter presented by Hani Abdelghani Mansour in collaboration with Ren Hongjouan, Hu Jiandong, Bao Hong Feng, and Liang Changmei, and entitled "*Performance of water desalination and modern irrigation systems for improving water productivity*". This chapter provides a brief update of the Egyptian water strategy for developing irrigation systems. This strategy is based on the promotion of alternative water sources (such as saline water) and, furthermore, the development of varieties of some traditional crops that are saline resistant by using genetic engineering through which saline-tolerant genes are added to the plant. Through field experiments conducted in Saudi Arabia to analyze the effect of different drip irrigation systems and different saline water concentrations on wheat grain yield, water productivity and ecological effects of using saline water are discussed.

In addition to ensuring irrigation system management and water productivity, environmental risks and climate change issues are equally disruptive to the semi-arid and arid regions on a short and medium term. The chapter presented by Muhammad Irfan, Abdul Qadir, Habib Ali, Nadia Jamil, and Sajid Rashid Ahmad and entitled "*Vulnerability of environmental resources in Indus Basin after the development of irrigation system*" informs the reader about both questions. This chapter recognizes the climatic and topographic characteristics of the Indus Basin, which provides an excellent example for the development of an irrigation system. However, in the race of extensive water use, the environmental resources of the Indus Basin have been compromised after 150 years of developing irrigation systems through the construction of dams, barrages, and canals to divert the maximum river water for irrigation. Consequently, water quality was degraded due to the addition of fertilizers, pesticides, chemicals, municipal sewage, and industrial effluents. To overcome this gap, the authors claim that to ensure ecological requirements at water basin scale and to address natural risks, one must promote water governance through key stakeholders. In order to do that, a review of the Indus Water Treaty is promoted with the aim to meet the environmental issues of changing climate and

Closing the book, the last chapter entitled "*Spate irrigation: Impact of climate change with specific reference to Pakistan*" and presented by Qudrat Ullah Khan and Obaid Ullah Sayal, describes the benefits and limitations of spate irrigation under the changing climate and how the promotion of storage dams could affect the hydrological system of the area and the irrigation practices. For example, the management of floodwater and perennial water has affected the water rights of the community and has changed the cropping pattern and land use, which was previously kept fallow and was now used for cultivation. Climate change can only exacerbate this situation. In fact, climate change has greatly influenced Pakistan

rising water tensions between India and Pakistan.

agricultural processes.

**1**

**Chapter 1**

**1. Introduction**

Introductory Chapter: Addressing

Challenges for Irrigation Systems

Water-agriculture nexus is context dependent (water availability and water use depend on spatial and temporal issues), socially constructed (multiple stakeholders' perceptions and interests interact), and technically uncertain (benefits from new technologies are difficult to be estimated and duly evaluated). This means that irrigation systems should be analyzed as hydrosocial cycles [1], which likewise takes into account all of these issues including how water management and water governance are conceived and how climate change impacts could be addressed through a "nexus" approach [2]. In few words, irrigation systems are under pressure to produce more food with lower supplies of water [3]. According to this, water availability and water consumption [4], food productivity and food security [5], environmental awareness [6], population growth [7], rural development [8], and climate change [9] are issues to be considered when irrigation systems are pro-

Past Claims and Oncoming

*Sandra Ricart, Jorge Olcina and Antonio M. Rico*

moted, developed, and managed both globally and locally.

**2. Irrigation water consumption: calling for concerted effort**

Globally, irrigation was by far the largest water consumer with a share ranging over time about 90% of global water consumption [10]. In addition, agriculture is the sector most affected by water scarcity, as it accounts for 70% of global freshwater withdrawals [11]. In fact, agriculture is both a cause and victim of water scarcity, as the excessive use and degradation of water resources is threatening the sustainability of livelihoods dependent on water and agriculture [12]. Furthermore, as the largest water user globally and a major source of water pollution, agriculture plays a key role in tackling the looming water crises. What can agriculture do to address water scarcity in the context of climate change, while ensuring food and nutrition security? What can irrigation offer to alleviate the impacts and reduce the risks of water scarcity? Both questions have been directly addressed through the achievement of the 2030 Agenda for Sustainable Development and the promotion of Sustainable Development Goals (SDG) [13]. These include the adoption of SDG-6 (*"Ensure availability and sustainable management of water and sanitation for all"*) and SDG-2 (*"End hunger, achieve food security and improved nutrition, and promote sustainable agriculture"*). Both goals are an opportunity to be engaged with key water-scarce countries to inform and orient national policies toward effective, sustainable models, and technologies of water management and food security [14]. Furthermore, both are in line with the Paris
