Abstract
One of the suggested approaches to mitigate the chronic groundwater depletion in California is agricultural managed aquifer recharge (Ag-MAR), in which farmland is flooded using excess surface water in order to recharge the underlying aquifer. Successful implementation of Ag-MAR projects requires careful estimation of the soil aeration status, as prolonged saturated conditions in the rhizosphere can damage crops due to O2 deficiency. We studied the soil aeration status under almond [Prunus dulcis (Mill.) D.A. Webb] trees and cover crops during Ag-MAR at three sites differing in drainage properties. Water application included several cycles (2–7) and flooding durations (27–63 h) that varied according to the soil infiltration capacity at each site. We used O2 and redox potential as soil aeration quantifiers to test the impact of forced aeration by air-injection compared with natural soil aeration. Results suggest an average increase of up to 2% O2 at one site, whereas mixed impact was observed at the two other sites. Additionally, no impact on crop yield was observed for one growing season. Results further suggest that natural aeration can support crop O2 demand during Ag-MAR if flooding duration is controlled according to O2 depletion rates. In large Ag-MAR projects, forced aeration might be useful to improve local zones of O2 deficiency, which are expected to occur due to topographic irregularities and spatial variability of drainage properties.
Original language | English |
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Article number | e20128 |
Journal | Vadose Zone Journal |
Volume | 20 |
Issue number | 3 |
DOIs | |
State | Published - 1 May 2021 |
Externally published | Yes |
Bibliographical note
Funding Information:We would like to thank Cristina Prieto Garcia for technical assistance during the instrumentation of the field sites. We thank Dale Pattigan, Rudy Gonzales, Vincent Silva, and their crew for technical support and yield data at KARE; Franz Niederholzer, Stan Cutter, and their crew for technical support and yield data at NSL; and Luis A Loza Reyes for technical support at CT. This research was supported by BARD, the United States–Israel Binational Agricultural Research and Development Fund Award no. IS‐5125‐18R and a Vaadia‐BARD Postdoctoral Fellowship Award no. FI‐579‐2018.
Publisher Copyright:
© 2021 The Authors. Vadose Zone Journal published by Wiley Periodicals LLC on behalf of Soil Science Society of America