The tourism industry contributes significantly to the growth of the global economy and is considered to be strongly associated with a large amounts of water and energy consumption. In this study, the tourism water footprint (TWF) and the tourism energy footprint (TEF) of 138 sectors were investigated to examine the water-energy-food (W-E-F) nexus in the Chinese tourism industry from 2012 to 2017 by developing the water- and energy-based environmentally extended input-output analysis with the tourism satellite account. This study revealed that the W-E-F supply groups consumed total 15,556 million m³ of water and 4,964 million tce of energy to support the Chinese tourism industry. The largest contributor to the total TWF is the indirect water use from the food supply group (65%), while the largest proportion of total TEF is contributed by the direct energy use from 11 tourism direct sectors (63%), most especially the air transport sector. A much larger growth of the tourism industry was observed in 2017 compared to that of 2012. The structure decomposition analysis revealed that the growth of the overall water and energy consumption of China tourism is mainly driven by the growth of the total tourism expenditure, i.e. the scale effect. It is the same case for the food supply group associated with the Chinese tourism industry. In contrast, the contribution of the changes to the tourism expenditure composition is relatively low. Furthermore, the growth in water and energy consumption can be offset effectively by reducing the water and energy use coefficient and adjusting the economic production structure of tourism and its associated food supply group. In sum, the food supply and air transport sectors play a crucial role in the water-energy-food nexus of the tourism industry. Therefore, in the future, focus should be placed on improving the water and energy use efficiency of these sectors as well as enhancing their production structures.

This study proposes a novel monitoring tool based on Satellite Remote Sensing (SRS) data to examine the status of water distribution and Water Use Efficiency (WUE) under changing water policies in large-scale and complex irrigation schemes. The aim is to improve our understanding of the water-food nexus in such schemes. With a special reference to the Gezira Irrigation Scheme (GeIS) in Sudan during the period 2000–2014, the tool devised herein is well suited for cases where validation data are absent. First, it introduces an index, referred to as the Crop Water Consumption Index (CWCI), to assess the efficiency of water policies. The index is defined as the ratio of actual evapotranspiration (ETa) over agricultural areas to total ETa for the whole scheme where ETa is estimated using the Simplified Surface Energy Balance model (SSEB). Second, the tool uses integrated Normalized Difference Vegetation Index (iNDVI), as a proxy for crop productivity, and ETa to assess the WUE. Third, the tool uses SSEB ETa and NDVI in an attempt to detect wastage of water. Four key results emerged from this research as follows: 1) the WUE has not improved despite the changing agricultural and water policies, 2) the seasonal ETa can be used to detect the drier areas of GeIS, i.e. areas with poor irrigation water supply, 3) the decreasing trends of CWCI, slope of iNDVI-ETa linear regression and iNDVI are indicative of inefficient utilization of irrigation water in the scheme, and 4) it is possible to use SSEB ETa and NDVI to identify channels with spillover problems and detect wastage of rainwater that is not used as a source for irrigation. In conclusion, the innovative tool developed herein has provided important information on the efficiency of a large-scale irrigation scheme to help rationalize laborious water management processes and increase productivity.

Efficient utilization of the limited Water, Energy, and Food (WEF) resources in stressed transboundary river basins requires understanding their interlinkages in different transboundary cooperation conditions. The Blue Nile Basin, a transboundary river basin between Ethiopia and Sudan, is used to illustrate the impacts of cooperation between riparian countries on the Water-Energy-Food nexus (WEF nexus). These impacts are quantified and evaluated using a daily model that simulates hydrological processes, irrigation water requirements, and water allocation to hydro-energy generation and irrigation water supply. Satellite-based rainfall data are evaluated and applied as a boundary condition to model the hydrological processes.The model is used to determine changes in the long-term economic gain (i.e. after infrastructure development plans are implemented and in steady operation) for each of Sudan and Ethiopia independently, and for the Blue Nile Basin from WEF in 120 scenarios. Those scenarios result from combinations of three cooperation states: unilateral action, coordination, and collaboration; and infrastructure development settings including the Grand Ethiopian Renaissance Dam and planned irrigation schemes in Sudan. The results show that the economic gain of the Blue Nile Basin from WEF increases with raising the cooperation level between Ethiopia and Sudan to collaboration. However, the economic gain of each riparian country does not necessarily follow the same pattern as the economic gain of the basin.