Facing water and land scarcity, planting non-food biofuel crops on marginal land depending on natural rainfall has been considered as an attractive means of achieving sustainable biofuel development. However, the complex connection between rainfall and marginal land resources in spatial-temporal distribution affects the optimal planting layout of non-food biofuel crops as well as the assessment of biofuel potential, especially in arid areas. In this study, we constructed a water-land-biofuel nexus centered on non-food biofuel crops, optimized the layout of three non-food biofuel crops, sweet sorghum, Jerusalem artichoke and switchgrass, based on fuzzy mathematics method under the water-land-biofuel nexus perspective, determined yield-rainfall curve to calculate the development potential of non-food biofuel crops. The results showed that sweet sorghum and Jerusalem artichoke are more suitable for planting in Ningxia. Three potential scenarios are set up under different growth conditions and agricultural technologies. The theoretical biofuel production is [9.64× 10⁷, 10.93× 10⁷] GJ, which was verified by the result that the biofuel production per unit area is close to the lower limit of the test production range. It can also be speculated that there may exist irrigation supply and fertilization in the actual crops planting in other studies.

High volumes of flowback and produced water are generated everyday as a byproduct of hydraulic fracturing operations and shale gas developments across the United States. Since most shale gas developments are located in semi-arid to arid U.S. regions close to agricultural production, there are many opportunities for reusing these waters as potential alternatives or supplements to fresh water resources for irrigation activities. However, the impacts of high salinity and total organic content of these types of water on crop physiological parameters and plant growth needs to be investigated to determine their utility and feasibility. The aim of the present study was to evaluate the response of switchgrass and rapeseed to treated produced water as an irrigation water source. In this greenhouse study, the influence of produced water at four total organic carbon (TOC) concentrations [1.22, 38.3, 232.2 and 1352.4mg/l] and three total dissolved solids (TDS) levels [400,3,500, and 21,000mg/l] on rapeseed (Brassica napus L.) and switchgrass (Panicum virgatum L.), two relatively salt-tolerant, non-food, biofuel crops, was studied. Seedling emergence, biomass yield, plant height, leaf electrolyte leakage, and plant uptake were evaluated. Irrigation water with the highest salinity and TOC concentration resulted in significantly lower growth health and physiological characteristics of both crop species. The organic content of the produced water had a negative impact on biomass yield and physiological parameters of both species. The results of this study could be valuable for regulators and stakeholders in development of treatment standards in which organic matter should be removed to less than 50mg/l to keep leaf EL (cell damage) to less than 50% and a TOC concentration of less than 5mg/l required to keep a sustainable biomass production rate.