Potential for Beneficial Reuse of Oil and Gas–Derived Produced Water in Agriculture: Physiological and Morphological Responses in Spring Wheat (Triticum aestivum)

Abstract

Produced water (PW) from oil and gas operations is considered a potential resource for food crop irrigation because of increasing water scarcity in dryland agriculture. However, efforts to employ PW for agriculture have been met with limited success. A greenhouse study was performed to evaluate the effects of PW on physiological and morphological traits of spring wheat (Triticum aestivum). Plants were irrigated with water treatments containing 10 and 50% PW (PW10 and PW50, respectively) and compared to a matching 50% salinity (NaCl50) and 100% tap water controls. Compared to controls, plants watered with PW10 and PW50 exhibited developmental arrest and reductions in aboveground and belowground biomass, photosynthetic efficiency, and reproductive growth. Decreases in grain yield ranged from 70 to 100% in plants irrigated with PW compared to the tap water control. Importantly, the PW10 and NaCl50 treatments were comparable for morphophysiological effects, even though NaCl50 contained 5 times the total dissolved solids, suggesting that constituents other than NaCl in PW contributed to plant stress. These findings indicate that despite discharge and reuse requirements focused on total dissolved solids, salinity stress may not be the primary factor affecting crop health. The results of the present study are informative for developing guidelines for the use of PW in agriculture to ensure minimal effects on crop morphology and physiology. Environ Toxicol Chem 2019;38:1756–1769. © 2019 SETAC

National Alliance for Water Innovation (NAWI) Agriculture Sector Technology Roadmap 2021

“…85 Traditionally, bulk organics in conventional PW may also limit both plant health and growth. 86,87 Pica et al recommended a TOC concentration of less than five mg/L to sustain biomass production rates. 88 A number of specific concerns regarding the level of treatment required and the uncertainty associated with PW's impacts on soil health must be resolved prior to widespread use of this resource for agriculture.…”

Emerging Trends in Biological Treatment of Wastewater From Unconventional Oil and Gas Extraction

“…Experiments simulating a PW spill (Niobrara, CO) on soil concluded that the high salt content of PW can disrupt soil structure and mobilize metal ions like copper, lead, aluminum and manganese during subsequent rainfall events (Oetjen et al, 2018a). Studies on irrigation of wheat with diluted untreated PW not only found reduction in plant development and yield (Sedlacko et al, 2019), but interestingly, a decrease in resistance to pathogens (Miller et al, 2019). Results of these studies indicate that factors beyond the salinity of PW, specifically concentrations of boron (salts of boron are added as crosslinkers) and nature of organic carbon, may play a major role in crop health and therefore must also be considered while determining the level of PW treatment necessary prior to use for irrigation.…”

Food Crop Irrigation with Oilfield-Produced Water Suppresses Plant Immune Response

“…A large concurrent study found that irrigation with PW leads to physiological changes and reduced yields in wheat . As a part of this study, we posed an additional and unique question: can water quality impact plant immune response?…”

“…Crop yield reduction due to pathogens result in millions of dollars lost per year, even with extensive pesticide use, thus further loss due to irrigation water quality would be problematic. To date, studies focused on the potential reuse of PW for agricultural irrigation have been human-health or plant-yield focused. ,− The immune response of crops irrigated with O&G PW and then subsequently infected with pathogens is, to our knowledge, unknown. If minimally treated PW proves to be a sustainable, inexpensive, and safe method of crop irrigation, it could be mutually beneficial to farmers in semiarid environments and to O&G companies.…”