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Evaluation of Technology Change Effects on Quantitative Assessment of Water, Energy and Food Nexus
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作者 Ali Karnib 《Journal of Geoscience and Environment Protection》 2017年第3期1-13,共13页
The quantitative assessment framework of the water, energy and food (WEF) nexus proposed by [1] permits the analysis of the WEF as an interconnected system of resources that directly and indirectly affect one another.... The quantitative assessment framework of the water, energy and food (WEF) nexus proposed by [1] permits the analysis of the WEF as an interconnected system of resources that directly and indirectly affect one another. The model performs simulation of policy options and scenarios that respond to quantitative variations of the use of WEF resources. One of the key outcomes of the mathematical formulation of the model is the WEF nexus intersectoral technology matrix. In order to take advantages and analyzing policy options of adopting high efficient intersectoral use technologies, WEF intersectoral use intensities and intersectoral allocation coefficients are introduced to the technology matrix of the nexus model proposed in [1]. The developed method is then applied to evaluate the WEF nexus case study of Lebanon. Lastly, the conclusions and further developments are presented. 展开更多
关键词 water energy food NEXUS Technology CHANGES SUSTAINABLE Development
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A Quantitative Assessment Framework for Water, Energy and Food Nexus 被引量:1
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作者 Ali Karnib 《Computational Water, Energy, and Environmental Engineering》 2017年第1期11-23,共13页
This paper presents a quantitative assessment framework of the Water, Energy and Food (W-E-F) nexus. The proposed approach allows integrated quantitative assessments by considering all the W-E-F intersectoral linkages... This paper presents a quantitative assessment framework of the Water, Energy and Food (W-E-F) nexus. The proposed approach allows integrated quantitative assessments by considering all the W-E-F intersectoral linkages and the competing demand for W-E-F resources to evaluate future development scenarios. Firstly, the conceptual model adopted for the proposed framework is presented. Secondly, a detailed methodological framework is introduced to serve as W-E-F nexus evaluation and planning platform. At the practical level, the model is applied to evaluate the W-E-F nexus in Lebanon. Finally, the conclusions and further developments are presented. 展开更多
关键词 water energy food NEXUS Approach SUSTAINABLE Development
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Hydrodynamic Performance of An Integrated System of Breakwater and A Multi-Chamber OWC Wave Energy Converter
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作者 NING De-zhi ZHANG Xiang-yu +1 位作者 WANG Rong-quan ZHAO Ming 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期543-556,共14页
A multi-chamber oscillating water column wave energy converter(OWC-WEC)integrated to a breakwater is investigated.The hydrodynamic characteristics of the device are analyzed using an analytical model based on the line... A multi-chamber oscillating water column wave energy converter(OWC-WEC)integrated to a breakwater is investigated.The hydrodynamic characteristics of the device are analyzed using an analytical model based on the linear potential flow theory.A pneumatic model is employed to investigate the relationship between the air mass flux in the chamber and the turbine characteristics.The effects of chamber width,wall draft and wall thickness on the hydrodynamic performance of a dual-chamber OWC-WEC are investigated.The results demonstrate that the device,with a smaller front wall draft and a wider rear chamber exhibits a broader effective frequency bandwidth.The device with a chamber-width-ratio of 1:3 performs better in terms of power absorption.Additionally,results from the analysis of a triplechamber OWC-WEC demonstrate that reducing the front chamber width and increasing the rearward chamber width can improve the total performance of the device.Increasing the number of chambers from 1 to 2 or 3 can widen the effective frequency bandwidth. 展开更多
关键词 oscillating water column power extraction efficiency potential flow theory wave energy converter multi-chamber
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Harvesting Energy Via Water Movement and Surface Ionics in Microfibrous Ceramic Wools
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作者 Manpreet Kaur Avinash Alagumalai +3 位作者 Omid Mahian Sameh M.Osman Tadaaki Nagao Zhonglin Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期332-341,共10页
Due to the push for carbon neutrality in various human activities,the development of methods for producing electricity without relying on chemical reaction processes or heat sources has become highly significant.Also,... Due to the push for carbon neutrality in various human activities,the development of methods for producing electricity without relying on chemical reaction processes or heat sources has become highly significant.Also,the challenge lies in achieving microwatt-scale outputs due to the inherent conductivity of the materials and diverting electric currents.To address this challenge,our research has concentrated on utilizing nonconductive mediums for water-based low-cost microfibrous ceramic wools in conjunction with a NaCl aqueous solution for power generation.The main source of electricity originates from the directed movement of water molecules and surface ions through densely packed microfibrous ceramic wools due to the effect of dynamic electric double layer.This occurrence bears resemblance to the natural water transpiration in plants,thereby presenting a fresh and straightforward approach for producing electricity in an ecofriendly manner.The generator module demonstrated in this study,measuring 12×6 cm^(2),exhibited a noteworthy open-circuit voltage of 0.35 V,coupled with a short-circuit current of 0.51 mA.Such low-cost ceramic wools are suitable for ubiquitous,permanent energy sources and hold potential for use as self-powered sensors and systems,eliminating the requirement for external energy sources such as sunlight or heat. 展开更多
关键词 ceramic microfibers energy harvesting power generation self-powered systems water evaporation
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Scenario-Based Assessment of the Water-Energy-Food Nexus in Kuwait: Insights for Effective Resource Management
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作者 Amani Al-Adwani Ali Karnib +1 位作者 Alaa Elsadek Waleed Al-Zubari 《Computational Water, Energy, and Environmental Engineering》 2024年第1期38-57,共20页
The interdependency among water, food, and energy (WEF) in the GCC countries is strongly and closely interlinked, and is intensifying as demand for resources increases with population growth and changing consumption p... The interdependency among water, food, and energy (WEF) in the GCC countries is strongly and closely interlinked, and is intensifying as demand for resources increases with population growth and changing consumption patterns, and are expected to be further compounded by the impacts of climate change. Therefore, integrated management of the three sectors is crucial to reduce trade-offs and build synergies among them. This paper presents a comprehensive framework to assess the WEF nexus in Kuwait as a representative case for the GCC countries. The framework consists of three main steps: 1) evaluating the influence of socio-economic development and climate change on water, energy, and food resources;2) generating scenario-based projections;and 3) conducting an extensive quantitative nexus analysis. The WEF interlinkages in Kuwait are modelled quantitatively using the Q-Nexus model, and current critical interdependencies are evaluated. Then, various WEF-Nexus scenarios were conducted for the year 2035 to explore the effects of management interventions in one sector on the other two sectors. The main findings are that per capita municipal water consumption is a major influencer on the WEF-nexus due to the heavy reliance on thermal desalination in municipal water supply in Kuwait, which is attributed to its energy intensity, financial cost, GHGs emissions, and environmental impacts on the marine and air environments. To reduce WEF trade-offs, mitigate risks, and build synergies among the three sectors, it is important to shift the current policy focus on supply-side management approach to the demand-side management and efficiency approaches. 展开更多
关键词 Climate Change Socio-Economic Development Municipal water Consumption Agricultural water Consumption Renewable energy Desalination Technology
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The Effect of Water Flow Velocity on Heat Collection Performance of Active Heat Storage and Release System for Solar Greenhouses
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作者 Wei Lu Lirui Liang +8 位作者 Dawei Shi Wenjun Peng Yangxia Zheng In-bok Lee Mengyao Li Qichang Yang Jiangtao Hu Xiaopei Tang Chengyao Jiang 《Journal of Electronic Research and Application》 2024年第6期79-88,共10页
In order to explore the influence of water velocity on the heat collection performance of the active heat storage and release system for solar greenhouses,six different flow rates were selected for treatment in this e... In order to explore the influence of water velocity on the heat collection performance of the active heat storage and release system for solar greenhouses,six different flow rates were selected for treatment in this experiment.The comprehensive heat transfer coefficient of the active heat storage and release system at the heat collection stage was calculated by measuring the indoor solar radiation intensity,indoor air temperature and measured water tank temperature.The prediction model of water temperature in the heat collection stage was established,and the initial value of water temperature and the comprehensive heat transfer coefficient were input through MATLAB software.The simulated value of water temperature was compared with the measured value and the results showed that the best heat transfer effect could be achieved when the water flow speed was 1.0 m3h-1.The average relative error between the simulated water tank temperature and the measured value is 2.70-6.91%.The results indicate that the model is established correctly,and the variation trend of water temperature can be predicted according to the model in the heat collection stage. 展开更多
关键词 Active heat storage and release water velocity Coefficient of heat transfer Modeling Solar energy
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Assessing the Water-Energy-Food-Ecosystems Nexus in Smart Irrigation: A Potato Farming Case Study in Lebanon
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作者 Ali Karnib Hammou Laamrani Jauad El Kharraz 《Journal of Geoscience and Environment Protection》 2024年第8期80-96,共17页
This study examines the Water-Energy-Food-Ecosystems (WEFE) nexus in Lebanese agriculture, with a focus on the shift from conventional surface irrigation techniques to advanced smart irrigation systems in the Bekaa re... This study examines the Water-Energy-Food-Ecosystems (WEFE) nexus in Lebanese agriculture, with a focus on the shift from conventional surface irrigation techniques to advanced smart irrigation systems in the Bekaa region, specifically targeting potato cultivation. The study quantitatively analyzes the interaction among water, energy, and agricultural outputs at the farm scale using the WEFE Nexus framework for scenario analysis. It evaluates variations in water productivity, environmental effects, and economic outcomes, offering a detailed view of existing practices and their sustainable improvement potential. The WEFE Nexus assessment demonstrates that smart irrigation integration significantly decreased resource usage: water consumption was reduced by 58%, diesel fuel use for irrigation dropped by 57%, and the demand for labor and fertilizers decreased by 47% and 49%, respectively. This change led to enhanced crop yields and increased resource efficiency, demonstrating the potential of smart irrigation as a transformative strategy for sustainable agriculture in Lebanon and other arid areas. Economic analysis showed that farmers could recover the costs of installing the smart irrigation system within 3 months. The findings highlight the need for further research on integrating smart irrigation with renewable energy, showing potential for sustainable agricultural development. . 展开更多
关键词 water-energy-food-Ecosystems Nexus Sustainable Agriculture Smart Irrigation Q-Nexus Model
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A comparative study of the land-atmosphere energy and water exchanges over the Tibetan Plateau and the Yangtze River Region
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作者 Nan Yao Yaoming Ma +3 位作者 Binbin Wang Jun Zou Jianning Sun Zhipeng Xie 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第2期52-59,共8页
正确认识不同区域能量和水分循环特征是研究局地地气相互作用及准确预测区域天气,气候变化的关键.为了研究属于干旱/半干旱气候的青藏高原(TP)和湿润/半湿润气候的长江流域(YRR)之间地表能量和水分交换的异同,本文对比分析了两个区域8... 正确认识不同区域能量和水分循环特征是研究局地地气相互作用及准确预测区域天气,气候变化的关键.为了研究属于干旱/半干旱气候的青藏高原(TP)和湿润/半湿润气候的长江流域(YRR)之间地表能量和水分交换的异同,本文对比分析了两个区域8个不同地表类型(包括高山荒漠,高山草地,(平原)城市和(平原)草地等)观测站点的地表辐射和能量通量数据.结果显示:(1)TP由于高原大气层稀薄且空气洁净,年平均入射短波辐射为251.3W m^(-2),是YRR的1.7倍.加之高原地表反照率高导致反射辐射(59.6 W m^(-2))是YRR的2.87倍.入射及出射的长波辐射为231.5和338.0 W m^(-2),分别为YRR的0.64和0.83.而两个区域的净辐射差异不大;(2)草地站更多的潜热释放使得地表总加热效率高于城市和高山荒漠,TP和YRR的草地站的年平均潜热分别为35.0和38.8 W m^(-2),而植被稀疏且土壤干燥的高山荒漠地区感热最大,年平均感热为42.1 W m^(-2);其次是城市下垫面,其年平均感热为37.7 W m^(-2).研究结果揭示了不同气候背景下典型下垫面地气相互作用特征,为地气相互作用过程深入分析奠定了基础. 展开更多
关键词 能量和水分交换 辐射分量 地表能量通量 青藏高原 长江流域 不同地表类型
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Water and Energy Conservation of Rainwater Harvesting System in the Loess Plateau of China 被引量:3
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作者 JIANG Zhi-yun LI Xiao-yan MAYu-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1389-1395,共7页
Water is the source of all the creatures on the earth and energy is the main factor driving the world. With the increasing population and global change, water and energy conservation have become worldwide focal issues... Water is the source of all the creatures on the earth and energy is the main factor driving the world. With the increasing population and global change, water and energy conservation have become worldwide focal issues, particularly in the water-stressed and energy-limited regions. Rainwater harvesting, based on the collection and storage of rainfall runoff, has been widely used for domestic use and agricultural production in arid and semiarid regions. It has advantages of simple operation, high adaption, low cost and less energy consumption. This study reviewed rainwater harvesting systems adopted in the Loess Plateau of China and analyzed water use efficiency (WUE) for various rainwater harvesting techniques. Supplemental irrigation using harvested rainwater could increase crop yield by more than 30%, and WUE ranged from 0.7 to 5.7 kg m4 for spring wheat, corn and flax, and 30-40 kg m-3 for vegetables. Moreover, energy consumption for rainwater harvesting based on single family was compared with traditional water supply in the city of the Loess Plateau using the life cycle assessment (LCA) method. Results showed that energy consumption yielded per unit harvested rainwater was 25.96 MJ m-3 yr which was much less than 62.25 MJ m3 yr^-1 for main water supply in Baoji City, Shanxi Province, meaning that rainwater harvesting saved energy by 139.8% as compared to the main water supply system. This study highlights the importance and potential of rainwater harvesting for water and energy conservation in the near future. 展开更多
关键词 rainwater harvesting water saving energy conservation life cycle assessment (LCA)
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Energy efficiency performance of multi-energy district heating and hot water supply system 被引量:2
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作者 金楠 赵靖 朱能 《Journal of Central South University》 SCIE EI CAS 2012年第5期1377-1382,共6页
A district heating and hot water supply system is presented which synthetically utilizes geothermal energy,solar thermal energy and natural gas thermal energy.The multi-energy utilization system has been set at the ne... A district heating and hot water supply system is presented which synthetically utilizes geothermal energy,solar thermal energy and natural gas thermal energy.The multi-energy utilization system has been set at the new campus of Tianjin Polytechnic University(TPU),A couple of deep geothermal wells which are 2 300 m in depth were dug,Deep geothermal energy cascade utilization is achieved by two stages of plate heat exchangers(PHE) and two stages of water source heat pumps(WSHP).Shallow geothermal energy is used in assistant heating by two ground coupled heat pumps(GCHPs) with 580 vertical ground wells which are 120 m in depth.Solar thermal energy collected by vacuum tube arrays(VTAs) and geothermal energy are complementarily utilized to make domestic hot water.Superfluous solar energy can be stored in shallow soil for the GCHP utilization.The system can use fossil fuel thermal energy by two natural gas boilers(NGB) to assist in heating and making hot water.The heating energy efficiency was measured in the winter of 2010-2011.The coefficients of performance(COP) under different heating conditions are discussed.The performance of hot water production is tested in a local typical winter day and the solar thermal energy utilization factor is presented.The rusults show that the average system COP is 5.75 or 4.96 under different working conditions,and the typical solar energy utilization factor is 0.324. 展开更多
关键词 geothermal energy solar thermal energy district heating hot water supply
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Energy and water saving by using modified closed circuits of drip irrigation system 被引量:1
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作者 Hani Abdel-Ghani Mansour Mohamed Yousif Tayel +1 位作者 David A. Lightfoot Abdel-Ghany Mohamed El-Gindy 《Agricultural Sciences》 2010年第3期154-177,共24页
The aim of this research was determine the en- ergy and water use efficiencies under the modification of closed circuit drip irrigation systems designs. Field experiments carried out on transgenic maize (GDH, LL3), (Z... The aim of this research was determine the en- ergy and water use efficiencies under the modification of closed circuit drip irrigation systems designs. Field experiments carried out on transgenic maize (GDH, LL3), (Zea Mays crop) under two types of closed circuits: a) One manifold for lateral lines or Closed circuits with One Manifold of Drip Irrigation System (CM1DIS);b) Closed circuits with Two Manifolds of Drip Irrigation System (CM2DIS), and c) Traditional Drip Irrigation System (TDIS) as a control. Three lengths of lateral lines were used, 40, 60, and 80 meters. PE tubes lateral lines: 16 mm diameter;30 cm emitters distance, and GR built-in emitters 4 lph when operating pressure 1 bar under Two levels slope conditions 0% and 2%. Experiments were conducted at the Agric. Res. Fields., Soil and Plant & Agric. System Dept., Agric. Faculty, Southern Illinois University, Car- bondale (SIUC), Illinois, USA. Under 0% level slope when using CM2DIS the increase percent of Energy Use Efficiency (EUE) were 32.27, 33.21, and 34.37% whereas with CM1DIS were 30.84, 28.96, and 27.45% On the other hand when level slope 2% were with CM2DIS 31.57, 33.14, and 34.25 while CM1DIS were 30.15, 28.98, and 27.53 under lateral lengths 40, 60 and 80 m respectively relative to TDIS. Water Use Efficiency (WUE) when level slope 0% under CM2DIS were 1.67, 1.18, and 0.87 kg/m3 compared to 1.65, 1.16, and 0.86 kg/m3 with CM1DIS and 1.35, 1.04, and 0.75 kg/m3 with TDIS whereas with level slope 2% when using CM2DIS were 1.76, 1.29, and 0.84 kg/m3 compared to 1.77, 1.30, and 0.87 kg/m3 with CM1DIS and 1.41, 1.12, and 0.76 kg/m3 (for lateral lengths 40, 60, and 80 meters respectively). Water saving percent varied widely within individual lateral lengths and between circuit types relative to TDIS. Under slope 0% level CM2DIS water saving percent values were 19.26, 12.48, and 14.03%;with CM1DIS they were 18.51, 10.50, and 12.78%;and under slope level 2% with CM2DIS they were 19.93, 13.26, and 10.38% and CM1DIS were 20.49, 13.96, and 13.23% (for lateral lengths 40, 60, 80 meters respectively). The energy use efficiency and water saving were observed under CM2DIS and CM1DIS when using the shortest lateral length 40 meters, then lateral length 60 meters, while the lowest value was observed when using lateral length 80 meters this result depends on the physical and hydraulic characteristics of the emitters, lateral line uniformity, and friction losses. CM2DIS was more energy use efficiency, EUE, water saving, and WUE than either CM1DIS or TDIS. 展开更多
关键词 DRIP IRRIGATION CLOSED CIRCUITS energy USE EFFICIENCY water USE EFFICIENCY
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An Integrated Framework for Regional Assessment of Water, Energy, and Nutrients from Food Loss of Selected Crops in the Lower Fraser Valley, Canada 被引量:1
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作者 Ana Reinesch Lewis Fausak +2 位作者 Anne Joseph Skylar Kylstra Les Lavkulich 《Agricultural Sciences》 2022年第5期633-657,共25页
Although there is no global shortage of food or water, food security has not been achieved, as human activity has turned these vital resources into “waste”. Wasted food not only loses valuable water resources but em... Although there is no global shortage of food or water, food security has not been achieved, as human activity has turned these vital resources into “waste”. Wasted food not only loses valuable water resources but embedded calories of human energy and nutrients for healthy human populations. The Food and Agricultural Organization of the United Nations, in addressing these concerns, focuses on a global scale largely on an economic estimate of individual components of energy or water or nutrient loss. It is suggested that more information is required through local or regional assessments to provide better estimates, incorporating regional factors of the losses along the food supply chain. To address this suggestion, this study focused on an intensive agricultural and rapidly urbanizing region of Canada, the Lower Fraser Valley of British Columbia. Seven selected crops, including annual crops such as green peas, sweet corn and potato, and perennial crops that included three berry crops were assessed for their water, both constituent and virtual, as well as embedded energy, protein, and Vitamin C. Annual virtual water losses were higher for sprinkler than drip irrigation, ranging from 82 × 10<sup>6</sup> kg of water for strawberry to 7570 × 10<sup>6</sup> kg for blueberry. These high virtual water losses estimated along the food chain confirm the significance of food loss impacts on local water resources. Estimates of losses of food in kg were highest at the consumer level along the food chain and it was estimated that wasted food from the seven crops selected would have supplied the protein and caloric energy of over 33,000 men per year and Vitamin C of about 240,000 men per year. This assessment increases the awareness of food loss impacts from a regional perspective and provides a framework for future research on both environmental and nutritional implications of wasted food. 展开更多
关键词 food Loss food Waste Crop water Demand Virtual water NUTRITION
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Impacts of Systematic Precipitation Bias on Simulations of Water and Energy Balances in Northwest America
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作者 Youlong XIA 徐国强 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第5期739-749,共11页
At high latitudes and in mountainous areas, evaluation and validation of water and energy flux simu-lations are greatly affected by systematic precipitation errors. These errors mainly come from topographic effects an... At high latitudes and in mountainous areas, evaluation and validation of water and energy flux simu-lations are greatly affected by systematic precipitation errors. These errors mainly come from topographic effects and undercatch of precipitation gauges. In this study, the Land Dynamics (LAD) land surface model is used to investigate impacts of systematic precipitation bias from topography and wind-blowing on water and energy flux simulation in Northwest America. The results show that topographic and wind adjustment reduced bias of streamflow simulations when compared with observed streamflow at 14 basins. These systematic biases resulted in a -50%-100% bias for runoff simulations, a -20%-20% bias for evapotranspiration, and a -40%-40% bias for sensible heat flux, subject to different locations and adjustments, when compared with the control run. Uncertain gauge adjustment leads to a 25% uncertainty for precipitation, a 20% 100% uncertainty for runoff simulation, a less-than-10% uncertainty for evapotranspiration, and a less-than-20% uncertainty for sensible heat flux. 展开更多
关键词 LaD model bias adjustment water and energy balance Northwest America
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Water, Energy and Nutrient Losses from Food Wastage of Selected Crops in Three Agro-Climatic Zones in British Columbia, Canada
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作者 Ana Reinesch Lewis Fausak +1 位作者 Anne Joseph Les Lavkulich 《Agricultural Sciences》 CAS 2022年第8期947-972,共26页
Food waste is a growing global concern. Data on the factors and magnitude are largely global estimates, thus local studies aid in providing information on the impacts of food waste. Three important agro-climatic zones... Food waste is a growing global concern. Data on the factors and magnitude are largely global estimates, thus local studies aid in providing information on the impacts of food waste. Three important agro-climatic zones in British Columbia and nine common crops, both annual and perennial, were selected to evaluate the environmental and nutritional implications of local food waste. Using Canadian estimates of total food waste, the constituent water, caloric content, protein, vitamin C, phosphorus and potassium wasted by each crop were estimated. Regionally, the total production and losses were the highest in the Lower Fraser Valley which had high production of potatoes and blueberries, followed by the Okanagan, with grapes and apples, and Vancouver Island, with potatoes. Virtual water was estimated by the BC Agriculture Water Calculator and used to assess the soil and climatic factors impacting the local water demand. Although soil texture seemed to influence water demand, the agro-climatic zone was the main factor controlling the water demand and the corresponding amount of water wasted. Dry agro-climatic zones had annual virtual water up to two times higher for the same crop and soil texture. Lower water demand crops, finer soils and more efficient irrigation systems were more congruent with water stress scenarios. Total losses for each region were based on conservative estimates and would have supplied the caloric energy and protein for over 40,000 adults, and vitamin C for over 300,000 adults for one year. Additionally, the total N, P and K wasted accounted for up to 32, 2 and 13 kg/ha respectively for common fertilizers used in British Columbia. This study confirmed the significance of food waste impacts on local water demand, human nutrition and soil management based on regional data for representative crops. 展开更多
关键词 food Loss food Waste Crop water Demand Virtual water NUTRITION
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OPTIMIZATION OF ELECTRIC HOT WATER RECIRCULATION SYSTEMS FOR COMFORT,ENERGY AND PUBLIC HEALTH
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作者 Randi H.Brazeau Marc A.Edwards 《Journal of Green Building》 2013年第2期73-89,共17页
Hot water recirculation systems(RECIRC)are labeled green and are sometimes mandated in local plumbing codes.Previous work conducted under non-optimized operation schemes demonstrated that these systems actually waste ... Hot water recirculation systems(RECIRC)are labeled green and are sometimes mandated in local plumbing codes.Previous work conducted under non-optimized operation schemes demonstrated that these systems actually waste energy and water versus standard(STAND)water heater counterparts.Optimization of RECIRC system operation by minimizing pump operation did improve energy efficiency 6-60%,saving consumers 5-140%annually in associated utility costs.However,STAND systems were still more energy efficient than any of the RECIRC systems.With respect to factors that might influence pathogen growth,reducing RECIRC pump operations increased disinfectant residual by as much as 560%as compared to the baseline RECIRC system;however,STAND systems still had 25-250%more total chlorine residual than any of the RECIRC systems.At 60℃operating temperature,STAND systems have 30-230%more volume at risk for pathogen growth(e.g.,volume with temp 37-46℃)than any of the RECIRC systems.Thus,in the context of“green”design,RECIRC systems provide a convenience to consumers in the form of nearly instant hot water,at a cost of higher capital,operating and overall energy costs.RECIRC systems have distinct advantages in controlling pathogens via thermal disinfection but disadvantages in control via secondary disinfection residual. 展开更多
关键词 water heaters energy efficiency water-energy nexus green energy premise plumbing temperature profiles
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Research on Solar Water Heating System and Architectural Integration Design—A Case Study of Anqing Children Welfare Home
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作者 梅小妹 苏剑鸣 《Journal of Landscape Research》 2010年第12期5-8,共4页
Taking the planning and major architectural design projects of Anqing Children Welfare Home for example,through the research on categories and each component of solar water heating system,the paper discussed strategie... Taking the planning and major architectural design projects of Anqing Children Welfare Home for example,through the research on categories and each component of solar water heating system,the paper discussed strategies and methods to realize solar energy and architectural integration design in the climate condition and location environment of Anhui Province. 展开更多
关键词 SOLAR energy SOLAR water HEATING system system selection ARCHITECTURAL integration
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Regional economic assessment of a novel place-based model for sustainable food systems
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作者 Susanna Kujala Kari Koppelmäki 《Geography and Sustainability》 CSCD 2024年第2期220-229,共10页
Several actions from both the environmental and human viewpoints have already been made to meet the sustainability goals targeted at food systems.Still,new place-based ideas to improve sustainability are needed.Agroec... Several actions from both the environmental and human viewpoints have already been made to meet the sustainability goals targeted at food systems.Still,new place-based ideas to improve sustainability are needed.Agroecological symbiosis(AES),a novel food system model,is an example of a suggested system-level change to attain sustainability targets;it is a symbiosis of food production and processing using renewable energy that uses its own feedstock.AES has already been found advantageous from the ecological and biophysical viewpoints,but a regional economic evaluation of the model is still lacking.Thus,the aim of our paper is to assess the regional economic impact of a possible systemic change in the food system using the network of agroecological symbiosis(NAES)as an example.We applied scenarios representing different ways of moving towards envisioned NAES models in Mäntsälä,Finland,and a computable general equilibrium model to evaluate the regional economic impact.According to our results,both regional economy and employment would increase,and the regional production base would diversify with NAES implementation applied to the region,but the extent of the benefits varies between scenarios.The scenario that includes change in both public and private food demand,production of bioenergy and utilization of by-products would cause the largest impacts.However,realizing NAES requires investments that may influence the actual implementation of such models.Nonetheless,a change towards NAES can promote an economically and spatially just transition to sustainability,as NAES seems to be economically most beneficial for rural areas. 展开更多
关键词 SUSTAINABILITY Regional economy Localized food system Renewable energy CIRCULARITY
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Rational design of natural leather-based water evaporator for electricity generation and functional applications
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作者 Bingyuan Zhang Xiaoyu Guan +10 位作者 Qingxin Han Haoxiang Guo Sai Zheng Xuhui Sun Afnan H.El-Gowily Mohammed A.Abosheasha Yanxia Zhu Motoki Ueda Meng An Haojun Fan Yoshihiro Ito 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期129-144,共16页
In recent years,water evaporation-induced electricity has attracted a great deal of attention as an emerging green and renewable energy harvesting technology.Although abundant materials have been developed to fabricat... In recent years,water evaporation-induced electricity has attracted a great deal of attention as an emerging green and renewable energy harvesting technology.Although abundant materials have been developed to fabricate hydrovoltaic devices,the limitations of high costs,inconvenient storage and transport,low environmental benefits,and unadaptable shape have restricted their wide applications.Here,an electricity generator driven by water evaporation has been engineered based on natural biomass leather with inherent properties of good moisture permeability,excellent wettability,physicochemical stability,flexibility,and biocompatibility.Including numerous nano/microchannels together with rich oxygen-bearing functional groups,the natural leather-based water evaporator,Leather_(Emblic-NPs-SA/CB),could continuously produce electricity even staying outside,achieving a maximum output voltage of∼3 V with six-series connection.Furthermore,the leather-based water evaporator has enormous potential for use as a flexible self-powered electronic floor and seawater demineralizer due to its sensitive pressure sensing ability as well as its excellent photothermal conversion efficiency(96.3%)and thus fast water evaporation rate(2.65 kg m^(−2)h^(−1)).This work offers a new and functional material for the construction of hydrovoltaic devices to harvest the sustained green energy from water evaporation in arbitrary ambient environments,which shows great promise in their widespread applications. 展开更多
关键词 energy conversion water evaporation-induced electricity Functional leather Flexible self-powered sensor DESALINATION
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Trade-offs and synergies between ecosystem services in Yutian County along the Keriya River Basin,Northwest China
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作者 ZUBAIDA Muyibul 《Journal of Arid Land》 SCIE CSCD 2024年第7期943-962,共20页
The Keriya River Basin is located in an extremely arid climate zone on the southern edge of the Tarim Basin of Northwest China,exhibiting typical mountain-oasis-desert distribution characteristics.In recent decades,cl... The Keriya River Basin is located in an extremely arid climate zone on the southern edge of the Tarim Basin of Northwest China,exhibiting typical mountain-oasis-desert distribution characteristics.In recent decades,climate change and human activities have exerted significant impacts on the service functions of watershed ecosystems.However,the trade-offs and synergies between ecosystem services(ESs)have not been thoroughly examined.This study aims to reveal the spatiotemporal changes in ESs within the Keriya River Basin from 1995 to 2020 as well as the trade-offs and synergies between ESs.Leveraging the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)and Revised Wind Erosion Equation(RWEQ)using land use/land cover(LULC),climate,vegetation,soil,and hydrological data,we quantified the spatiotemporal changes in the five principal ESs(carbon storage,water yield,food production,wind and sand prevention,and habitat quality)of the watershed from 1995 to 2020.Spearman correlation coefficients were used to analyze the trade-offs and synergies between ES pairs.The findings reveal that water yield,carbon storage,and habitat quality exhibited relatively high levels in the upstream,while food production and wind and sand prevention dominated the midstream and downstream,respectively.Furthermore,carbon storage,food production,wind and sand prevention,and habitat quality demonstrated an increase at the watershed scale while water yield exhibited a decline from 1995 to 2020.Specifically,carbon storage,wind and sand prevention,and habitat quality presented an upward trend in the upstream but downward trend in the midstream and downstream.Food production in the midstream showed a continuously increasing trend during the study period.Trade-off relationships were identified between water yield and wind and sand prevention,water yield and carbon storage,food production and water yield,and habitat quality and wind and sand prevention.Prominent temporal and spatial synergistic relationships were observed between different ESs,notably between carbon storage and habitat quality,carbon storage and food production,food production and wind and sand prevention,and food production and habitat quality.Water resources emerged as a decisive factor for the sustainable development of the basin,thus highlighting the intricate trade-offs and synergies between water yield and the other four services,particularly the relationship with food production,which warrants further attention.This research is of great significance for the protection and sustainable development of river basins in arid areas. 展开更多
关键词 ecosystem services trade-offs SYNERGIES water yield food production habitat quality wind and sand prevention Tarim Basin
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Impact of Initial Soil Conditions on Soil Hydrothermal and Surface Energy Fluxes in the Permafrost Region of the Tibetan Plateau
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作者 Siqiong LUO Zihang CHEN +3 位作者 Jingyuan WANG Tonghua WU Yao XIAO Yongping QIAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期717-736,共20页
Accurate initial soil conditions play a crucial role in simulating soil hydrothermal and surface energy fluxes in land surface process modeling.This study emphasized the influence of the initial soil temperature(ST)an... Accurate initial soil conditions play a crucial role in simulating soil hydrothermal and surface energy fluxes in land surface process modeling.This study emphasized the influence of the initial soil temperature(ST)and soil moisture(SM)conditions on a land surface energy and water simulation in the permafrost region in the Tibetan Plateau(TP)using the Community Land Model version 5.0(CLM5.0).The results indicate that the default initial schemes for ST and SM in CLM5.0 were simplistic,and inaccurately represented the soil characteristics of permafrost in the TP which led to underestimating ST during the freezing period while overestimating ST and underestimating SLW during the thawing period at the XDT site.Applying the long-term spin-up method to obtain initial soil conditions has only led to limited improvement in simulating soil hydrothermal and surface energy fluxes.The modified initial soil schemes proposed in this study comprehensively incorporate the characteristics of permafrost,which coexists with soil liquid water(SLW),and soil ice(SI)when the ST is below freezing temperature,effectively enhancing the accuracy of the simulated soil hydrothermal and surface energy fluxes.Consequently,the modified initial soil schemes greatly improved upon the results achieved through the long-term spin-up method.Three modified initial soil schemes experiments resulted in a 64%,88%,and 77%reduction in the average mean bias error(MBE)of ST,and a 13%,21%,and 19%reduction in the average root-mean-square error(RMSE)of SLW compared to the default simulation results.Also,the average MBE of net radiation was reduced by 7%,22%,and 21%. 展开更多
关键词 initial soil conditions soil temperature soil liquid water soil ice surface energy fluxes PERMAFROST
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