Oil and gas extraction in the western United States generates significant volumes of produced water (PW) that is typically injected into deep disposal wells. Recently, crop irrigation has emerged as an attractive PW reuse option, but the impact on plant immune response is not known. In this study, we conducted a 3-month greenhouse pot study. Spring wheat (Triticum aestivum) was irrigated 3 times a week with 150 mL (∼80–100% of soil water holding capacity) with one of four irrigation treatments: tap water control, 10% PW dilution, 50% PW dilution, and salt water (NaCl50) control containing the same amount of total dissolved solids as PW50 to determine the effect on disease resistance. The wheat leaves were inoculated with either bacterial or fungal pathogens and changes in pathogenesis-related PR-1 and PR-5 gene expression were measured from the leaf tissue. PW50 experienced the largest relative suppression of PR-1 and PR-5 gene expression compared to noninfected wheat, followed by PW10, NaCl50, and the tap water control. A combination of PW contaminants (boron, total petroleum hydrocarbons, and NaCl) are likely reducing PR-gene expression by reallocating metabolic resources to fight abiotic stresses, which then makes it more challenging for the plants to produce PR genes to fight pathogens. This study provides the first evidence that plant disease resistance is reduced due to irrigation with reused PW, which could have negative implications for food security.

This paper presents the first groundwater‒energy‒food (GEF) nexus study of Iran’s agronomic crops based on national and provincial datasets and firsthand estimates of agricultural groundwater withdrawal. We use agronomic crop production, water withdrawal, and energy consumption data to estimate groundwater withdrawal from electric-powered irrigation wells and examine agronomic productivity in Iran’s 31 provinces through the lens of GEF nexus. The ex-post GEF analysis sheds light on some of the root causes of the nation’s worsening water shortage problems. Access to highly subsidized water (surface water and groundwater) and energy has been the backbone of agricultural expansion policies in Iran, supporting employment in agrarian communities. Consequently, water use for agronomic crop production has greatly overshot the renewable water supply capacity of the country, making water bankruptcy a serious national security threat. Significant groundwater table decline across the country and increasing energy consumption underscore dysfunctional feedback relations between agricultural water and energy price and groundwater withdrawal in an inefficient agronomic sector. Thus, it is essential to implement holistic policy reforms aimed at reducing agricultural water consumption to alleviate the looming water bankruptcy threats, which can lead to the loss of numerous agricultural jobs in the years to come.

Irrigated agriculture is the backbone of Central Asian economies. Therefore, efficient irrigation water management is of crucial importance to the sustainable crop production in the region. Presented here are two studies aiming to improve agricultural water productivity â?? ET-based irrigation scheduling in Uzbekistan; and valuation of ecosystem services in Kazakhstan. The ET-based irrigation scheduling method has potential to replace subjective daily water management decisions at Water Users Association level with crop water demand-based decisions to improve water-use efficiency. Results from a two year study show that there can be a 32-35% saving of water when irrigation is applied using the ET-based scheduling method. The pilot plots are representative of 38% of irrigated area in Fergana Valley (241,407ha) and 50% in Khorezm (137,500ha) area. If this methodology is widely adopted, large amounts of water can be saved which can be diverted for other purposes. Flood irrigation of cotton is practiced on 128,000ha in the Bugunski Reservoir watershed of Kazakhstan. This practice is unsustainable due to seasonal unavailability in water supply and depletion of river discharges that were historically important at maintaining water levels downstream in nearby wetlands and the Aral Sea. Farmer surveys were used along with RIOS and SWAT modeling to evaluate alternative irrigation practices and cropping systems that can conserve water from the Bugunski Reservoir while maintaining farmer incomes. Simulations show significant reductions in irrigation water demand in the alternative scenario relative to the baseline scenario. Under baseline flood irrigation of cotton, annual irrigation demand was 928 MCM/yr averaged over the 32 year climatic record simulated. Irrigation demand decreased by 38% to 573 MCM/yr when 40,439ha of flood irrigated cotton was converted to drip irrigated cotton, sprinkler irrigated alfalfa and drip irrigated grapes. This represents a savings of 355 MCM/yr in water extracted from irrigation canals and groundwater wells | Vinay Nangia. (7/11/2016). Managing Scarce Water Resources in Irrigated Agri-Food Systems of Central Asia Two Case Studies. Phoenix, United States: American Society of Agronomy.

In India, the nexus between water, food and energy has reached a tipping point. The country can no longer underestimate the crises or delay addressing the issues emanating from the nexus, which already constrain sustainable economic growth in many regions. This paper assesses the trends and turning points of groundwater irrigation, agricultural production and energy consumption in the state of Andhra Pradesh (AP), India, which exemplifies the dire situation that prevails elsewhere in the country. It also shows that the state can reduce agricultural electricity consumption and still achieve a Pareto optimal solution for all stakeholders: farmers, utility companies, the government and, most importantly, the environment. AP has an important place in economic, agricultural land- and water-scape in India. In 2011, the total population of India was 1.2 billion, of which AP accounted for 84 million people. Among the 32 major states in India, AP has the fifth largest population, fourth largest geographical area, second largest economy and 5 million hectares of net irrigated area (NIA), which is 9% of the total NIA of the country. The state has 23 administrative districts in three agro-climatic zones: Telangana, Rayalaseema and Coastal Andhra. Three distinct growth periods depict groundwater irrigation development during the last four decades. Dug wells, along with canals, were the main sources of irrigated area expansion in the 1970s and 1980s. A decline in the number of dug wells and the rapidly increasing number of tube wells were the main features of irrigation development trends in the 1990s. Post-2000 trends show a significant slowdown in the expansion of even the tube well irrigated area. Yet, groundwater depletion is an issue in many regions. Groundwater contributes to 69%, 67% and 23% of NIA in the Telangana, Rayalaseema and Coastal Andhra regions, respectively, and to 48% of the net sown area in AP. In some regions, the consumptive water use (CWU) (evapotranspiration) of crop production alone is a significant part of natural groundwater recharge. With depletion from other sectors, groundwater CWU in many locations are at or above the thresholds of natural groundwater recharge. Electricity consumption increased rapidly with groundwater use. The share of electric pumps in the state increased from 64% to 94% between 1991 and 2008. As a result, agricultural electricity consumption increased by 138% between 1991 and 2008, compared to a 57% growth in NIA using groundwater. Electricity supply is free to farmers, but a high cost has to be borne by the governments. Utility companies estimate the cost of agricultural electricity supply at a flat rate of about USD 0.08/kWh. The government transfers the estimated subsidy to the utility companies to mitigate their losses. The estimated farm power subsidy at the national level is more than USD 6 billion, which is more than the expenditure for health and education in some states. Econometric analyses of district-level data between 1999 and 2008 show that, every 1% growth in groundwater CWU has contributed to a 0.82% increase in agricultural electricity consumption and only a 0.12% gross value of crop output. Thus, a 1% reduction in agricultural electricity consumption will reduce 1.14% of groundwater CWU and will, in turn, reduce 0.14% of the gross value of output. At present, the marginal loss of gross value of output due to a reduction in electricity consumption is far less than the increase in subsidy for that amount of electricity consumed. In many districts, due to high production costs, marginal profits are much less than the subsidy that the government has to payout. Thus, the direct transfer of the electricity subsidy to farmers for reducing electricity consumption is a financially attractive option, rather than the value generated in agricultural production at present. Such a solution can generate even higher environmental and socioeconomic benefits to all stakeholders. It will maintain, at least, the present level of benefits to farmers - the most important stakeholder in the nexus. Power utility companies can reduce losses by selling power to other sectors at a higher incremental rate. The state government can reduce the agricultural power subsidy. Domestic and industrial sectors can increase their productivity and output, for which inadequate power supply is a severe constraint at present. The environment will benefit by reduced groundwater depletion, which contributes to the drying of wetlands and streams, and water quality issues, at present. It is an incentive for farmers to increase efficiency of groundwater use and diversify cropping patterns to high-value low water-intensive crops. The utility companies will have to reduce losses in power transmission and distribution, which, at present, is conveniently included in the subsidy estimation

Hydraulic fracturing—the injection of pressurized fluid, often water, to increase recovery of oil or gas—has become increasingly popular in combination with horizontal drilling. Hydraulic fracturing improves production from a well, but requires a significant amount of water to do so and could put pressure on existing water resources, especially in water-stressed areas. To supply water needs, some water rights holders sell or lease their water resources to oil and gas producers in an informal water market. These transactions enable the opportunity for cross-sectoral investments, by which the energy sector either directly or indirectly provides the capital for water efficiency improvements in the agricultural sector as a mechanism to increase water availability for other purposes, including oil and gas production. In this analysis, we employ an original water and cost model to evaluate the water market in Texas and the potential for cross-sectoral collaboration on water efficiency improvements through a case study of the Lower Rio Grande Valley in Texas. We find that, if irrigation efficiency management practices were fully implemented, between 420 and 800 million m3 of water could be spared per year over a ten year period, potentially enabling freshwater use in oil and gas production for up to 26,000 wells, while maintaining agricultural productivity and possibly improving water flows to the ecosystem.

In India, the nexus between water, food and energy has reached a tipping point. The country can no longer underestimate the crises or delay addressing the issues emanating from the nexus, which already constrain sustainable economic growth in many regions. This paper assesses the trends and turning points of groundwater irrigation, agricultural production and energy consumption in the state of Andhra Pradesh (AP), India, which exemplifies the dire situation that prevails elsewhere in the country. It also shows that the state can reduce agricultural electricity consumption and still achieve a Pareto optimal solution for all stakeholders: farmers, utility companies, the government and, most importantly, the environment. AP has an important place in economic, agricultural land- and water-scape in India. In 2011, the total population of India was 1.2 billion, of which AP accounted for 84 million people. Among the 32 major states in India, AP has the fifth largest population, fourth largest geographical area, second largest economy and 5 million hectares of net irrigated area (NIA), which is 9% of the total NIA of the country. The state has 23 administrative districts in three agro-climatic zones: Telangana, Rayalaseema and Coastal Andhra. Three distinct growth periods depict groundwater irrigation development during the last four decades. Dug wells, along with canals, were the main sources of irrigated area expansion in the 1970s and 1980s. A decline in the number of dug wells and the rapidly increasing number of tube wells were the main features of irrigation development trends in the 1990s. Post-2000 trends show a significant slowdown in the expansion of even the tube well irrigated area. Yet, groundwater depletion is an issue in many regions. Groundwater contributes to 69%, 67% and 23% of NIA in the Telangana, Rayalaseema and Coastal Andhra regions, respectively, and to 48% of the net sown area in AP. In some regions, the consumptive water use (CWU) (evapotranspiration) of crop production alone is a significant part of natural groundwater recharge. With depletion from other sectors, groundwater CWU in many locations are at or above the thresholds of natural groundwater recharge. Electricity consumption increased rapidly with groundwater use. The share of electric pumps in the state increased from 64% to 94% between 1991 and 2008. As a result, agricultural electricity consumption increased by 138% between 1991 and 2008, compared to a 57% growth in NIA using groundwater. Electricity supply is free to farmers, but a high cost has to be borne by the governments. Utility companies estimate the cost of agricultural electricity supply at a flat rate of about USD 0.08/kWh. The government transfers the estimated subsidy to the utility companies to mitigate their losses. The estimated farm power subsidy at the national level is more than USD 6 billion, which is more than the expenditure for health and education in some states. Econometric analyses of district-level data between 1999 and 2008 show that, every 1% growth in groundwater CWU has contributed to a 0.82% increase in agricultural electricity consumption and only a 0.12% gross value of crop output. Thus, a 1% reduction in agricultural electricity consumption will reduce 1.14% of groundwater CWU and will, in turn, reduce 0.14% of the gross value of output. At present, the marginal loss of gross value of output due to a reduction in electricity consumption is far less than the increase in subsidy for that amount of electricity consumed. In many districts, due to high production costs, marginal profits are much less than the subsidy that the government has to payout. Thus, the direct transfer of the electricity subsidy to farmers for reducing electricity consumption is a financially attractive option, rather than the value generated in agricultural production at present. Such a solution can generate even higher environmental and socioeconomic benefits to all stakeholders. It will maintain, at least, the present level of benefits to farmers - the most important stakeholder in the nexus. Power utility companies can reduce losses by selling power to other sectors at a higher incremental rate. The state government can reduce the agricultural power subsidy. Domestic and industrial sectors can increase their productivity and output, for which inadequate power supply is a severe constraint at present. The environment will benefit by reduced groundwater depletion, which contributes to the drying of wetlands and streams, and water quality issues, at present. It is an incentive for farmers to increase efficiency of groundwater use and diversify cropping patterns to high-value low water-intensive crops. The utility companies will have to reduce losses in power transmission and distribution, which, at present, is conveniently included in the subsidy estimation