Allocation of water specifically to the environment (often dubbed ‘environmental water’ or ‘environmental flows’) can be contentious within government, among irrigators and between community members. The reduction in supply of fresh water has led to questions surrounding the efficiencies and ecological value of securing these adequate flows for waterways. This literature review examines the evidence on these perceptions of environmental water allocations, focusing foremost on general public, irrigator, Indigenous and decision-maker perspectives. Existing studies are predominantly in Global North areas such as Australia, Canada and the USA. Two themes featured strongly in the papers: the importance of personal values in the acceptance of environmental water and the perception of fairness in environmental water allocation processes. Although the research area has been expanding, there is still limited representation in types of study, disciplinary backgrounds and study locations, and as such many research opportunities remain.

We have developed a convenient and effective XRF analysis procedure for trace amount of K, Ca, V, Mn, Fe, Ni, Cu, Zn, Cd, and Pb in environmental waters by using a preconcentration using the natural polymer (agar). The thin agar film was prepared by drying a homogeneous agar gel after mixing the aqueous sample solution with the agar powder. XRF analysis of the preconcentrated thin agar films containing trace metals showed a good repeatability because agar films were homogeneous enough. SB (signal to noise) ratios of the XRF intensity of the analytes were improved drastically. The linear calibration curves of K, Ca, V, Mn, Fe, Ni, Cu, Zn, Cd, and Pb showed a good linearity within the calibration ranges. The lower limits of detection (LLD) were 1.4 μg/mL for K, 0.26 μg/mL for Ca, 0.088 μg/mL for V, 0.029 μg/mL for Mn, 0.11 μg/mL for Fe, 0.016 μg/mL for Ni, 0.030 μg/mL for Cu, 0.017 μg/mL for Zn, 0.20 μg/mL for Cd, and 0.066 μg/mL for Pb, respectively. The proposed preconcentration method was applied to several environmental water samples.