Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

United States Department of Agriculture (USDA) National Institute of Food and Agriculture

Titre : RECYCLED WATER IRRIGATION : CROP PAIRING AND IRRIGATION ALTERNATION TO MINIMIZE CEC ACCUMULATION IN FOOD PRODUCE

Identification : 1030211

Pays : Etats Unis

Durée : START : 01 JUN 2023 TERM : 31 MAY 2027

Résumé
Changing precipitation patterns and population growth are putting unprecedented stress on freshwater supply, posing formidable challenges to the sustainability of irrigation agriculture. Treated wastewater (recycled water) is one of several nontraditional water sources that may be used to augment agricultural irrigation. However, recycled water irrigation introduces numerous chemicals of environmental concern (CECs) into agroecosystems. The potential accumulation of CECs in food represents a significant hurdle to the broader adoption of this practice. Research to date has stopped at surveying occurrence of CECs in plants, while risk-mitigation strategies are urgently needed to truly advance nontraditional water use in agriculture. In response to the program area "Water Quantity and Quality" (A1411), this research is focused on novel strategies to minimize CEC accumulation in edible plant tissues. Through a comprehensive field-plot study, we will demonstrate that CEC accumulation in fruiting row crops (e.g., tomato, pepper, cucumber, melon, bean) is limited. We will further evaluate CEC accumulation in fruit trees (e.g., apple, peach, citrus, avocado) that are common in arid and semi-arid regions to test the hypothesis that CEC accumulation in tree fruits is low. Study findings will allow the pairing of specific crop types with recycled water use to minimize CEC accumulation. We will also explore the use of irrigation alternation, i.e., recycled water irrigation early in the season, followed by conventional freshwater irrigation, to achieve further reductions in CEC accumulation. The project contributes to sustainable U.S. agriculture by offering several safe reuse practices of nonconventional water to strengthen water security in agriculture.

Objectifs
The overall aim of this project is to develop implementable strategies to minimize CEC accumulation in food produce when using recycled water for irrigation. Field studies, coupled with greenhouse/laboratory experiments and modeling, will be carried out. Specifically, we will:1) Under field conditions with recycled water irrigation, evaluate CEC accumulation in the edible part of non-fruiting and fruiting row crops. The derived BCFs in edible tissues and human exposure from dietary consumptions will be used to test the hypothesis that fruits generally have reduced CEC accumulation.2) Under field conditions, compare accumulation of CECs in tree fruits produced with recycled and conventional water. Given the large biomass, long growing season, and distinct physiology of perennial fruit trees, CEC accumulation from recycled water irrigation in tree fruits may be very limited. Validation of this assumption improves our understanding of contaminant uptake, translocation, and accumulation in fruit trees, providing an opportunity for greatly expanding the scope of using nontraditional water for agricultural irrigation.3) Under greenhouse and field conditions, quantify further reductions in CEC accumulation in fruits by alternating recycled water and potable water for irrigation. When recycled water is used only for the first half of a growing season, CEC accumulation in edible organs is minimized due to extensive metabolism and growth

Financement total : $750,000

Performing Institution : UNIVERSITY OF CALIFORNIA, RIVERSIDE
Investigator : Gan, J.

Présentation : USDA (NIFA)