A Comprehensive Evaluation Framework of Water-Energy-Food System Coupling Coordination in the Yellow River Basin,China

For mankind’s survival and development,water,energy,and food(WEF)are essential material guarantees.In China,however,the spatial distribution of WEF is seriously unbalanced and mismatched.Here,a collaborative governance mechanism that aims at nexus security needs to be urgently established.In this paper,the Yellow River Basin in China with a representative WEF system,was selected as a case.Firstly,a comprehensive framework for WEF coupling coordination was constructed,and the relationship and mechanism between them were analyzed theoretically.Then,we investigated the spatiotemporal characteristics and driving mechanisms of the coupling coordination degree(CCD)with a composite evaluation method,coupling coordination degree model,spatial statistical analysis,and multiscale geographic weighted regression.Finally,policy implications were discussed to promote the coordinated development of the WEF system.The results showed that:1)WEF subsystems showed a significant imbalance of spatial pattern and diversity in temporal changes;2)the CCD for the WEF system varied little and remained at moderate coordination.Areas with moderate coordination have increased,while areas with superior coordination and mild disorder have decreased.In addition,the spatial clustering phenomenon of the CCD was significant and showed obvious characteristics of polarization;and 3)the action of each factor is self-differentiated and regionally variable.For different factors,GDP per capita was of particular importance,which contributed most to the regional development’s coupling coordination.For different regions,GDP per capita,average yearly precipitation,population density,and urbanization rate exhibited differences in geographical gradients in an east-west direction.The conclusion can provide references for regional resource allocation and sustainable development by enhancing WEF system utilization efficiency.

Water-Energy-Food Nexus： Background and Perspectives for Brazil and the United States by 2050

Rapid economic growth, increasing populations and emergent prosperity are driving up demand tor energy, water anu food, especially in developing countries. In this scenario, the analysis of these three elements has gained the increasing attention globally in research, business and policy spheres. This paper aims to provide an analysis of the perspectives of this nexus for Brazil and the United States, using current and predicted scenario for 2050. Considering the importance of renewable sources of energy to overcome these challenges and diversify the energy matrix in both countries, the paper will also present the biogas potential for both countries, which provides multiple economic, environmental and social benefits, such as electrical, thermal and vehicular energy, high-quality biofertilizer, reduction of odor and pathogenic vectors in the farms, decrease of ground and surface water pollution, promotion of new income for the farmers, reduction of the greenhouse gases emissions, among others.

Comment： Closing phosphorus cycle from natural waters： re-capturing phosphorus through an integrated water-energy-food strategy

Phosphorus （P） reserve, largely derived from phosphate rock, is essential for crop growth to support the growing world population. However, a significant proportion of phosphorus used as a fertilizer runs into natural waters, causing eutro- phication and ecological damage. Moreover, most P in the food is eventually discharged as waste after being digested by human and animals. Thus, industrial activities have created a one-way flow of non-renewable P from rocks to farms to lakes, rivers and oceans.

地理大数据挖掘——“水-能源-粮食”纽带研究的新机遇

Since the Bonn 2011 conference,the“water-energy-food”(WEF)nexus has aroused global concern to promote sustainable development.The WEF nexus is a complex,dynamic,and open system containing interrelated and interdependent elements.However,the nexus studies have mainly focused on natural elements based on massive earth observation data.Human elements(e.g.,society,economy,politics,culture)are described insufficiently,because traditional earth observation technologies cannot effectively perceive socioeconomic characteristics,especially human feelings,emotions,and experiences.Thus,it is difficult to simulate the complex WEF nexus.With the development of earth observation sensor technologies and human activity perception methods,geographical big data covering both human activities and natural elements offers a new opportunity for in-depth WEF nexus analysis.This study proposes a five-step framework by leveraging geographical big data mining to dig for the hidden value in the data of various natural and human elements.This framework can enable a thorough and comprehensive analysis of the WEF nexus.Some application examples of the framework,major challenges,and possible solutions are discussed.Geographical big data mining is a promising approach to enhance the analysis of the WEF nexus,strengthen the coordinated management of resources and sectors,and facilitate the progress toward sustainable development.