Teaching irrigation science and water management: accepting professional diversity. Editorial

Abstract

Water matters in a world that will soon have to grow food for billions more people. In that context, how should we educate aspiring professionals in the field of irrigation and water resource management? Before attempting an answer to that question we need to explore how the practice and science of irrigation have changed in recent decades.First, we outline the history of irrigation development, identifying the important research issues that were characteristic for each period. The intent is to delineate major trends in the profession, highlighting those changes with implications for university curricula in irrigation and water management. The second part of the paper reviews selected curriculum reform literature and discusses the practicalities of changing from a disciplinary curriculum to multi-or interdisciplinary teaching and research in irrigation and water management. The final section discusses the desired difference between the irrigation curriculum and the water management curriculum.The history of irrigation science and practice with a focus on developing countries Irrigation expansionHalf a century ago, irrigation was considered one of the branches of civil engineering, rather than a scientific endeavor. Hydraulics, hydrology, soil science (mechanics, physics and chemistry), and economics constituted the scientific basis for irrigation engineering. The goal-the so-called 'hydraulic mission'-during this period, lasting from the end of World War II till about the 1970s, was the construction of irrigation systems. The design and construction of hydraulic control and measurement structures were based on hydraulic principles that facilitated controlled flow in open channels and closed conduits for piped distribution systems and sprinkler irrigation.1 Hydrology dealt with the study of rainfall patterns and runoff models and studied the loss of water through evaporation and transpiration from cropped land. Several algorithms were developed for the calculation of actual and potential evapotranspiration from sets of meteorological data. Together, hydraulics and hydrology were essential for the design of large dams and reservoirs for water storage to be used for irrigation and hydropower, especially in the US (for example along the Colorado River), but also in the Indian subcontinent. The construction of such dams required the study of soil mechanics.Chiefly in South Asia, this period also marked the beginning of an increase in water supplies for irrigation through public and private development of groundwater. Combined with other inputs of the green revolution, irrigated agriculture contributed much to achieving food security and poverty reduction in countries which hitherto had been plagued by periodic famines. The study of groundwater hydrology expanded with the development of groundwater as an additional source of irrigation water. Horst (1998), especially chap. 1 in which the author examines irrigation development over time in support of his proposition that the design of the physical canal system with it...

Construction of Multimedia Teaching Resource Management Evaluation Model in the Big Data Environment

“…In this context, the multimedia teaching resource management evaluation model in the big data environment has gradually shown its value [7]. In view of the deficiencies in the studies of multimedia teaching resource construction method and resource management evaluation model at present, a multi-media teaching resource management evaluation model is first proposed in this paper based on the ontology and hypergraph theory [8][9][10]. Guided by the model, the construction method for the multimedia teaching resource management evaluation model is studied in the open big data environment.…”

Irrigation water planning for crops in the central highlands of Ethiopia, aided by FAO CROP WAT MODEL

“…Water supply matters in the world that will soon have to grow food for billions more people as world population is projected to peak at 9.3 billion in 2050, an increase of 28%. Analysis showed that the total crop water requirement of all major crops increased with the rising temperature thereby increasing the simulated irrigation water demand (Kijne, 2010;Surendran et al, 2014). In the future, food and livelihood security may be challenged due to global environmental changes, particularly global climatic changes that evidence has *Corresponding author.…”

Water and salt balances of two shallow groundwater cropping systems using subjective and objective irrigation scheduling

“…Research over recent decades has contributed tremendously to the advancement of on-farm water and salt management (Oster and Wichelns, 2003;Hillel and Vlek, 2005;Kijne, 2006;Kijne, 2011). Means became available to utilize rainfall and groundwater within or just below the potential root zone, as a water source to supply in crop water requirements (Ayars et al, 2006;Jhorar et al, 2009;Isidoro and Grattan, 2011;Singh, 2013).…”

“…Salt tends to accumulate in poorly drained soils under irrigation if inadequate water and salt management practices are applied. Furthermore, overirrigation may deteriorate the quality of water resources, because of salt pollution resulting from excessive drainage and leaching (United States Salinity Laboratory Staff, 1954;Van Schilfgaarde, 1990;Letey, 1994;Rhoades, 1997;Hillel, 2000;Oster and Wichelns, 2003;Hillel and Vlek, 2005;Kijne, 2006;Le Roux et al, 2007;Van Rensburg et al, 2008;Van Rensburg et al, 2011). The days when the sole purpose of irrigation was to increase crop production are now in the distant past.…”

“…The days when the sole purpose of irrigation was to increase crop production are now in the distant past. Farmers are under increasing pressure, specifically to prevent the degradation of water resources, and also to produce higher yields with less water (Hillel and Vlek, 2005;Pott et al, 2009;Kijne, 2011). Advocates for a more sustainable irrigation sector attempt to empower farmers and encourage them to continually evaluate and improve on-farm water and salt management (Kijne, 2006).…”