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A combination of a changing global climate coupled with rapid socio-economic development is putting unprecedented pressure on water, energy, and food resources. Addressing these issues within a nexus approach can help to identify appropriate management practices and strategic policies to ensure natural resources are used more sustainably thus avoiding exacerbating issues of water scarcity and food insecurity. In this study, we used an integrated water resource planning and irrigation model (WEAP) to assess emerging water-energy nexus issues on the Santa Elena peninsula in Ecuador. Simulated water demands showed that current water resources availability is insufficient to meet full irrigation requirements, especially during the dry season. Annual average energy demand for water conveyance in the SEP was significantly higher than for irrigation with 94.5 GWh and 13.5 GWh being used, respectively. Future challenges associated with changes in agricultural irrigation and urban demands within the SEP were evaluated using scenario analysis. This included considering various scenarios such as agricultural expansion, climate change, population growth, and a shift to export-oriented agriculture. The study underscores the significance of nexus thinking in guiding policy and decision-making in Santa Elena, although the limited data prevents its use in an operational framework. The benefits of adopting an integrated modelling approach to analyse water and energy nexus trade-offs are also discussed. [Display omitted] • An integrated reservoir simulation modelling approach for nexus analysis is used. • Water-energy nexus trade-offs during baseline and future scenarios are considered. • The system is unable to meet irrigation demand under baseline and all scenarios. • Energy demand for conveyance system is seven times higher than for irrigation. • Infrastructure expansion and more efficient agriculture needed if scenarios realise. [ABSTRACT FROM AUTHOR]

The water footprint concept has been used by agricultural, commercial, and industrial water users to measure and report their water consumption, assess the magnitude of potential environmental impacts arising from this consumption, and identify opportunities for risk mitigation strategies that promote sustainable water use. However, water and wastewater utilities have not studied and documented the application of this concept in the same manner that other industries have. This article summarizes the growing body of information on the water footprint concept and the opportunities for integrating the concept into water utility planning efforts as a broader means of achieving and maintaining sustainable communities. The application of the water footprint concept for capital improvement planning, water resources decision-making, operational benchmarking, and stakeholder communications is discussed, as is how the methodology, developed by the International Organization for Standardization, can be used for a water utility. [ABSTRACT FROM AUTHOR]

Data from the Woburn Erosion Reference Experiment (Bedfordshire, UK) were used to test the hypothesis that losses of phosphorus (P) in small erosion events are as great as those in infrequent large events, and to examine the effect of storm characteristics on the selective enrichment of P in eroded sediment. For almost every plot event in the period 1988 to 1994, the clay‐sized fraction of the sediment was enriched compared with the soil of the plots. There was more variation in clay enrichment for smaller erosion events than for larger ones. The clay and P contents of the sediment were strongly correlated (p < 0.01), and there was a wider range of P concentrations in the sediment derived from small events than in that from large events. However, individual events resulting in small soil losses (<100 kg) did not account for greater P losses than larger events (>100 kg). The greater frequency of smaller events, combined with the likelihood of higher P concentrations in the sediment, therefore accounted for a greater proportion of the P lost over the 6‐yr period than the infrequent large events. Phosphorus concentrations generally increased with increasing peak discharge and decreased with increasing event duration. For the same return period, P losses were generally greater from plots cultivated up and down the slope than from those cultivated across the slope. Overall, our results suggest that small erosion events should be controlled to prevent P contamination of surface waters and that the most effective means of doing this are by the introduction of minimal tillage techniques and across‐slope cultivations. [ABSTRACT FROM AUTHOR]

• Irrigation efficiency is more than a performance indicator or water-savings panacea. • Managing irrigation efficiency supports water, food and energy goals. • Insufficient understanding of irrigation efficiency may impede policy goals. • The meanings and use of irrigation efficiency depend on spatial scale and viewpoint. • A matrix of scales and dimensions is proposed to explore irrigation efficiency. An effective placement of irrigation efficiency in water management will contribute towards meeting the pre-eminent global water challenges of our time such as addressing water scarcity, boosting crop water productivity and reconciling competing water needs between sectors. However, although irrigation efficiency may appear to be a simple measure of performance and imply dramatic positive benefits, it is not straightforward to understand, measure or apply. For example, hydrological understanding that irrigation losses recycle back to surface and groundwater in river basins attempts to account for scale, but this generalisation cannot be readily translated from one location to another or be considered neutral for farmers sharing local irrigation networks. Because irrigation efficiency (IE) motives, measures, effects and technologies play out at different scales for different people, organisations and purposes, and losses differ from place to place and over time, IE is a contested term, highly changeable and subjective. This makes generalisations for science, management and policy difficult. Accordingly, we propose new definitions for IE and irrigation hydrology and introduce a framework, termed an 'irrigation efficiency matrix', comprising five spatial scales and ten dimensions to understand and critique the promises, pitfalls and paradoxes of IE and to unlock its utility for addressing contemporary water challenges. [ABSTRACT FROM AUTHOR]

Due to chronic immunosuppression, heart transplant recipients are at risk for developing malignancy, compromising long-term survival. A subset of our veteran heart transplant recipients have been exposed to Agent Orange, an herbicide which is linked to the development of hematologic malignancies and soft tissue sarcoma. We hypothesized that Agent Orange exposure would lead to a higher prevalence of post-transplant malignancy and decreased survival. We conducted a retrospective chart review of all 188 heart transplant patients who received their longitudinal care at the William S. Middleton Memorial Veterans Hospital since the program's inception on Oct. 1, 1993. Demographic data were collected for each patient. Proof of Agent Orange exposure was based on VA administrative review of service records. Univariate analysis was conducted to identify variables linked to the incidence of cancer. Multivariate analysis using a Cox Proportional Hazard Model was used to assess the influence of Agent Orange on the development of malignancy and post-transplant survival. Kaplan Meier analyses were used to assess survival and the incidence of cancer, stratified by Agent Orange exposure. Of the 188 patients, 113 have died. Malignancy accounted for 28% of the deaths. Fifty three percent of the patients developed malignancy after transplant (n = 100). Seventy seven developed skin cancer (41%), 46 developed solid organ cancer (24%), and 5 developed hematologic cancer (3%). Twenty nine patients were diagnosed with multiple malignancies (15%). Sixteen percent of our patients were exposed to Agent Orange (n=31). Univariate predictors of developing malignancy included older age at time of transplant (p<0.001), Caucasian race (skin cancer only), and pre-transplant ischemic cardiomyopathy (p=0.017). Multivariate analysis demonstrated that age at time of transplant reduced survival (p=0.021) and increased the likelihood of developing skin (p<0.0001) but not solid organ cancer. Agent Orange exposure did not affect overall survival (Figure 1) or risk for developing solid organ cancer but did increase the likelihood of acquiring basal cell carcinoma (p=0.019). Of the 5 patients who developed hematologic malignancy, 3 had Agent Orange exposure (p = 0.032). Survival and risk for developing solid organ malignancy following heart transplant were not influenced by Agent Orange contact. While the incidence of hematologic malignancy post-transplant was low, Agent Orange exposure may have contributed. [ABSTRACT FROM AUTHOR]