Beyond 2020, Vision of the Future: Selected Papers from the Sixth Decennial National Irrigation Symposium

HighlightsASABE/IA 6th National Irrigation Symposium includes 80 papers, with 36 introduced here in this Special Collection.Papers include current irrigation research about ET, management, turf systems, technology, humid region, water supply.Irrigation in the U.S. is growing more rapidly in humid regions, and pressurized irrigation continues to grow in usage.There has been much progress in irrigation science in the last decade, and the vision of the future looks bright.Abstract. This article introduces the ASABE Special Collection associated with the 6th Decennial National Irrigation Symposium: Beyond 2020, Vision of the Future. This U.S. symposium, jointly sponsored by ASABE and the Irrigation Association in December 2021, was postponed from 2020 due to the pandemic and consists of approximately 80 presentations, of which 36 were accepted as journal articles for this Special Collection. Irrigated land area appears to be growing slightly in the U.S. but is shifting geographically somewhat toward humid regions. Pressurized irrigation continues to grow, and gravity-fed irrigation continues to decline. Competition for stressed water resources among diverse water users remains great, and smaller numbers of irrigation scientists are available to meet the informational needs. Improved ability to acquire, assess, and use water and crop information helps to meet these challenges. This article discusses irrigation research progress in evapotranspiration (ET), irrigation management, turf systems, sensors and technologies, irrigation strategies in the humid region, and water supply. Challenges and opportunities continue to exist for irrigation in the U.S., but progress in the last decade has been steady, and a good vision for the future of irrigation beyond 2020 is anticipated. Keywords: Evapotranspiration, Irrigation, Irrigation management, Irrigation scheduling, Irrigation systems, Turf and landscape irrigation.

Monitoring of soil moisture and irrigation forecast under the condition of drip irrigation in greenhouse

The accurate prediction of the soil moisture in greenhouse can improve the accuracy of irrigation forecast, thus saving water and increasing production. In this paper, the monitoring data were obtained from the greenhouse in Agricultural Demonstration Park of Northland Spring, Wuqing District, Tianjin. The soil moisture was predicted based on the GM (1,1) model, and the effect of water-saving and increased production was tested with the results of the economic irrigation research in the same area. The results show that the GM (1,1) model has a higher accuracy of soil moisture prediction. The correlation coefficient (R2) of the predicted value and the measured value is higher than 0.9; the small error probability P is 1; the mean relative prediction errors are all less than 0.1. Therefore, the GM (1,1) model can be used to predict soil moisture content.

A Semi-Systematic Review of Capillary Irrigation: The Benefits, Limitations, and Opportunities

Capillary irrigation systems have been investigated for some years as a means to deliver water to plants in container gardening. This review paper identifies that traditional capillary irrigation systems such as capillary wicks, capillary mats, and ebb and flow systems have been shown to produce higher crop yields and use less water than conventional irrigation methods. In addition, capillary irrigation offers an added advantage by reducing the volume of potentially harmful leachate into surrounding soil environments. However, these systems are basically limited to small pot sizes and are widely used for growing ornamental and nursery plants in glasshouse conditions. Further, the cost and complexity of Negative Pressure Difference Irrigation may have limited its practical use. Conversely, wicking beds (WBs) are low-tech and water-efficient systems which can be used for growing plants with different rooting depths. Irrespective of the wide acceptance of WBs among the growing community, this review recognises that there is no published research providing design recommendations for WBs and their expected performance relative to other irrigation systems. Therefore, some potential advantages of WBs are noted in the context of capillary irrigation research; however, a substantial knowledge gap exists relating to the optimised design and use of WBs.

FERTIGATION FOR CITRUS TREES

Microirrigation is an important component of citrus production systems in Florida. For citrus trees, microirrigation is more desirable than other irrigation methods for several reasons: water conservation, fertilizer management efficiency, and freeze protection. Research has shown that when microirrigation systems are properly managed, water savings can amount to as much as 80% compared with subirrigation and 50% compared with overhead sprinkler irrigation. Research has also shown the important advantage of microsprinklers for freeze protection of citrus. This 4-page fact sheet discusses fertilizer solubility and some common fertigation materials. It also offers a fertigation summary. Written by Mongi Zekri, Arnold Schumann, Tripti Vashisth, Davie Kadyampakeni, Kelly Morgan, Brian Boman, and Tom Obreza, and published by the UF Horticultural Sciences Department, September 2017.