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Advanced Tools for Irrigation Scheduling
Published in Guangnan Chen, Advances in Agricultural Machinery and Technologies, 2018
Susan A. O’Shaughnessy, Ruixiu Sui
Although water for agriculture is becoming limited in regions of North America, the United States is well-positioned to help meet globalized agricultural demands (Macdonald et al., 2015). Currently, at least 65% of irrigated land in the United States is watered with pressurized irrigation systems, while 35% is irrigated with gravity flow systems (Figure 11.1) (NASS, 2013). These percentages are almost a complete reversal from the amount of irrigated area watered by pressurized and gravity flow systems in the 1980s (Howell, 2001). Accompanied by the increase in pressurization was a decrease in average water withdrawals (207 to 159 billion m3) for irrigation (ERS, 2013). The transition from gravity flow irrigation methods to pressurized systems not only helped to increase water application efficiency, but has also benefited farmers by enabling better irrigation control and reducing labor expenses; perhaps the best example is the center pivot irrigation system.
Sprinkler irrigation
Published in Mohammad Albaji, Introduction to Water Engineering, Hydrology, and Irrigation, 2022
Center pivot irrigation is a form of sprinkler irrigation consisting of several segments of pipe (usually galvanized steel or aluminum) joined together and supported by trusses, mounted on wheeled towers with sprinklers positioned along its length. The system moves in a circular pattern and is fed with water from the pivot point at the center of the arc. These systems are found and used in all parts of the world and allow irrigation of all types of terrain. Newer systems have drop sprinkler heads as shown in the image that follows.
Nitrate pollution and expansion of free-floating plants in 3 lower Wisconsin River oxbow lakes
Published in Lake and Reservoir Management, 2023
David W. Marshall, Kenneth Wade, Jean L. Unmuth
Aerial photos dating back to 1937 demonstrated that agriculture had been the dominant land use across the Pleistocene sand terrace for many decades. Beginning in 1992, linear and center pivot irrigation systems began to appear across the terrace and rapidly expanded into the 21st century (Schlaudt 2017). The linear irrigation system (Fig. 5) was installed in 2018. The irrigation systems require high-capacity wells, which are permitted and tracked by the state (Smail 2015). Increased numbers of high-capacity well permits were issued across the sand terrace and are consistent with expanded irrigation. High yield corn is typically produced on irrigated droughty soils that require higher nitrogen inputs due to rapid NO3-N leaching into the groundwater (Matson 2017). While data were not available for individual farms, cropland nitrogen applications across Wisconsin increased roughly 35% from 2004 to 2014, in response to higher corn prices (Matson 2017). The vulnerability of the Pleistocene sand terrace to leaching and groundwater contamination had been recognized decades ago (WDNR and Wisconsin Geological and Natural History Survey 1989). The increased groundwater NO3-N within the last 20 yr could have been predicted. In many parts of the Driftless Area uplands, water quality improvements were associated with long-term conservation programs designed to reduce soil erosion (Marshall et al. 2008). In the flat sand terrace, soil erosion has not been a problem, while agriculture became more industrialized to maximize crop production with irrigation, requiring additional nutrients.
Water-energy nexus: A systematic analysis and evaluation of a center-pivot irrigation system
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2022
Mohamed Brik, Ayoub Guerrah, Abdelmalek Atia
The criteria for selecting the farms for the study were based on (1) the existence of center pivot irrigation systems, and (2) the variability of crops. Experimental field surveys were carried out during the period of 2019–2020 on 3 farms, one farm on site A and two farms on site B. The selection of these farms was based on their owners farming experience among a large number and diversity of farmers, especially in site B, to adopt their irrigation strategy in this work. The survey with growers using a face-to-face questionnaire to describe and understand their irrigation strategies mainly consisted of a questionnaire including the following: planting and harvesting schedule, agricultural practices, conventional irrigation planning, production, characteristics of water resources of the farm, and in addition, the source of electricity used.
Computational modeling of wastewater land application treatment systems to determine strategies to improve carbon and nitrogen removal
Published in Journal of Environmental Science and Health, Part A, 2019
Younsuk Dong, Steven I. Safferman, A. Pouyan Nejadhashemi
A center pivot irrigation system is typically used for food processing wastewater application. More frequent application requires more energy, which leads to higher operation costs. The tradeoffs of increasing nitrate removal to increase energy demand and carbon emissions must be considered in deciding if changing to a larger number of daily doses is warranted for a site-specific condition.