Green Blue Water Research Articles

Crop water footprints and their driving mechanisms show regional differences

Identifying crop water footprints and their driving mechanisms is of significant importance for regional water resources management and ecological sustainability. However, there is currently a lack of comparative studies on drivers of crop water footprint among multiple regional types. In this study, based on quantifying the crop water footprints in seven regions (North China, Northeast China, East China, Central China, South China, Southwest China, and Northwest China) in mainland China from 1996 to 2020, the path analysis method was used to reveal their driving mechanisms. The results showed that the average annual agricultural water footprint was 1448.2 Gm3, with blue water, green water, and grey water accounting for 10.1 %, 66.6 %, and 23.3 %, respectively. Fruits and cereals jointly contributed 80 % of the total water footprint. The crop water footprint in East China was significantly higher than in other regions, accounting for 29.3 % of the national water footprint. The average crop production water footprint was 1080.4 mm, with the highest values observed in East China and South China, and the lowest in Northeast China and Southwest China. Except for East China, the crop production water footprint in other regions showed an increasing trend over time. Irrigation area ratio had the greatest impact on crop production water footprint except for Northeast China, while chemical fertilizer consumption significantly influenced crop production water footprints in North, East, Central, Southwest and Northwest China. Additionally, per capita GDP, per capita net income and irrigation water use efficiency also had considerable effects on crop production water footprint in Northwest China. The research findings can provide a valuable reference for the development of strategies for the efficient and sustainable utilization of agricultural water resources in different regions.

Assessing water security and footprint in hypersaline Lake Urmia

The quantitative assessment of water security including its distribution helps plan and manage adequate amounts of quality water to sustain livelihoods. This research introduces a hydrological modeling framework designed to evaluate the spatial and temporal fluctuations of blue water and green water, aiming to quantify the water security status of Lake Urmia in Iran. This lake, recognized as the second largest hypersaline lake globally, has experienced a significant decline in its water storage in recent years. This model, based on water consumption and population size was used to investigate water security and footprint while quantifying the spatial and temporal changes in the availability of blue water and green water. As the results demonstrate, the monthly and annual coefficient of variation for blue water (41.1 % and 27.6%, respectively) was greater than for green water (32.3% and 21.7%, respectively), hence green water flow showed more homogeneous than blue water flow distribution among different sub-basins. At the same time, the coefficient of variation for the spatial distribution differs between various components of the water footprint. Agricultural use requires the most water in this basin, with a blue water scarcity of 0.27. The blue water vulnerability value for total water consumption indicates a lower risk of a water crisis under low-flow conditions. In addition, the freshwater provision indicator in each sub-basin varies between the middle (0.64) and lower (0.80) parts. Thus, in these parts, water can be consumed with less negative impact on the environment. In conclusion, the environmental situation of Lake Urmia and its water security has clearly decreased over the last decade which requires urgent management action (e.g., changing irrigation pattern) to mitigate an environmental crisis. This research offers precise and quantifiable references related to water resources and water security, and can enhance targeted water footprint management within the study area. Our hydrological modeling framework provides the basis to inform water management in various similar watersheds across the globe.

The coupling of agricultural water footprint and socioeconomic development in ecological functional zones: A case study of Gansu Province, China

Water footprint accounting can evaluate the real occupancy of water resources by combining the consumption of blue water and green water. In this study, we calculated agricultural water footprint (AWF) including six patterns of crops water footprint (CWF) and three patterns of animal products water footprint (APWF) from 2000 to 2020 in Gansu Province, China, then the spatiotemporal matching pattern and its heterogeneity of AWF and socioeconomic factors were identified at the ecological functional zone level. The results show that: (1) The AWF showed a rising trend, increasing by 40%. (2) The spatial difference of AWF was obvious, the main contributor to the CWF changed from wheat to maize, and the main contributors to the APWF were always pork and beef. At the ecological zones level, the central and eastern Loess Plateau and Hexi inland areas together accounted for 60% of the total AWF of Gansu Province. (3) The center of gravity of AWF was always located in Lanzhou, the provincial capital, but tended to gradually move to the northwest. (4) The spatiotemporal matching degree between AWF and population and GDP was relatively good, but it was highly unbalanced between blue water footprint (BWF) and planting area. Considering both water-saving potential and feasibility, we suggest that Gansu Province should carry out sustainable agricultural management from three aspects, that is, optimizing the planting structure, emphasizing water conservation in animal husbandry, and improving the spatial matching degree between AWF and socioeconomic factors.

Blue-green water resource availability dynamics in the upper Awash basin, central Ethiopia: implications for agricultural water scarcity assessment

Quantifying and characterizing the spatial distribution of freshwater availability and water scarcity plays an indispensable role in managing water resources in a basin. This study aimed at quantifying green and blue water resource availability using an eco-hydrological model under different land use land cover conditions between 2000–2010 and 2020 in the upper Awash basin, central Ethiopia. Further, the agricultural water scarcity is assessed for dominantly cultivated crops in the basin. The freshwater components such as the green water (GW) flow (∼1041–1240 mm/yr), blue water (BW) flow (277–304 mm/yr), and GW storage (809-872 mm/yr) were observed to be high in the western highlands compared to the central and eastern parts of the basin. The results of GW scarcity indices show low to moderate scarcity for rainfed crops, and moderate to significant BW scarcity for irrigated sugarcane. Integrating GW potential to reduce BW scarcity in the basin is thus crucial.

Landscape and Horticultural Fertigation Using Roof-Derived Storm Water: The Potential Multiple Benefits of Blue Green Roof Installations

A contribution to the sustainable management of storm water is the use of sustainable drainage (SuDS)-derived water as an unconventional source for irrigation. If storm-water runoff contains dissolved nutrients in excess of those found in conventional irrigation, reusing this water can contribute to the nutrient demands of horticulture or landscaping, which is known as “fertigation”. Green roofs are SuDS devices, and those with below-substrate water storage, blue green roofs, can be additional water sources. The nutrients released from a roof-substrate-growing medium could contribute to the growth of crop and landscape plants, but materials from blue green roofs must not release residues harmful to fertigated plants or receiving soils. This plant growth experiment examined the effects of water from a blue green roof on plant growth and health and the effects on soil and roof-harvested water when functioning as a nutrient-rich irrigation source. Tomatoes and ryegrass were used as examples of horticultural and landscaping plants, respectively. Blue green roof water was compared with potable water irrigation. The blue-green-roof-derived water provided a distinct growth advantage for tomatoes and lower sodium in fruits than tap water, at 285 mg/kg and 636 mg/kg, respectively. For ryegrass, the differences were minimal, but there was no disadvantage to using roof water for fertigation. Following three years of a blue green roof’s operational life, export of inorganic nutrients from the roof, local storage, and then application to plants were effective in contributing additional fertiliser.

Cropping pattern optimization considering water shadow price and virtual water flows: A case study of Yellow River Basin in China

Cropping pattern determines the agricultural water use requirement and efficiency, as well as economic benefits of crop production. Agricultural water resources include blue water (irrigation water) and green water (soil moisture from precipitation), which have different shadow prices. The virtual water (VW) flow embedded in the interregional food trade causes burden shifts of water resources pressures in space. However, these intertwined economic and social effects have been neglected in regional cropping structure management. Using the case of the Yellow River Basin in China, here, we propose a two-stage multi-objective cropping pattern optimization scheme to maximize crop economic output, while minimize blue water scarcities (the first stage), and considered the criteria of maximum economic benefits of the interprovincial crop-related VW flows based on the shadow prices of crop green and blue water use (the second stage). Results show considerable differences in shadow prices of crop water use by colures, crops and location. With the optimized cropping pattern, which appropriately expands the planting scale of vegetables with higher water shadow price and comparative advantage and reduces the crop planting with lower water shadow price and intensive blue water consumption (e.g., soybean and wheat), blue water scarcity can be alleviated by ∼20%, combined with a ∼5% increase in crop economic output and up to ∼3% (800 million USD) higher benefits of VW flows. The premise to achieve above goals is to improve crop water resources utilization efficiency and break down the barriers of dietary preferences and trade policy.

Validation of conventional and synchronous fluorescence emission of potable water

Water from filter plants and bottled water is generally safe to drink but regular quality monitoring of these facilities requires development of quick analytical technique to ensure public safety and health. This study presented the variation of two components in spectra of conventional fluorescence spectroscopy (CFS) and four components in synchronous fluorescence spectroscopy (SFS) to assess the quality of 25 water samples from different sources. Poor quality water either due to organic or inorganic contaminants presented high intensity fluorescence emission in the blue green region and low intensity water Raman peak unlike an intense water Raman peak originated from pure water when excited at 365 nm. Emission intensity in the blue green region and water Raman peak can be used as a marker for quick screening of water quality. Although few discrepancies were observed in CF spectra of samples with intense Raman peak but were found to be positive for bacterial contamination, thus questioning the sensitivity of CFS that needs to be addressed. Whereas, SFS presented highly selective and detailed picture of water contaminants emitting aromatic amino acid, fulvic and humic like fluorescence. It is suggested that the specificity of CFS can be enhanced by coupling it with SFS or use of multiple excitation wavelengths to target different fluorophores for water quality analysis.

Effects of Climate Change, Land Use and Land Cover Variability on Green and Blue Water in Wami/Ruvu Basin, Tanzania

Water basins are the primary food sources, giving green water and blue water worldwide. Despite the basins’ potential, information on the periodical variations in blue water and green water is sparse, particularly in developing countries. The study specifically evaluated the changes in land use and land cover variability (LULCV), effects of land use and land cover variability on green water and blue water variations, and effects of climatic changes on green water and blue water. The evaluation involved the Enhanced Thematic Mapper and Operational Land Imager satellite images of 1990, 2000, 2010 and 2020. Image processing utilized the Soil and Water Assessment Tool (SWAT) in ArcGIS software. The land use and land cover variabilities indicated that land use supporting social-economic activities increased, while natural land cover decreased. Proportionally, blue water per annum was decreasing due to declining natural vegetation, enhanced by the increased socio-economic activities. Whereas, the increase in green water per annum was due to the increased temperatures, boosted by climate changes. Since the temperature rise is mainly uncontrolled, greenhouse farming should be encouraged for making green water more productive in agriculture and communities should be encouraged to practice environmentally friendly anthropogenic activities for sustainable green water and blue water management.
 Keywords: Basin, Green water, Blue water, SWAT model, Climate change

How did blue and green water resource evolute spatially and temporally in the Meijiang River Basin, China?

Water is the source of all life on Earth. Blue water and green water are important for water resource evaluation and are also essential for the efficient use of water resources. By constructing a SWAT model to simulate the spatiotemporal evolution of blue water and green water resources in the Meijiang River Basin from 2008 to 2018, this paper explored the spatiotemporal distribution characteristics of blue water and green water and evaluated the change trend of the green water coefficient. The results showed that: 1) the average amount of blue water resources per unit area in the Meijiang River Basin was 921 mm, accounting for 43% of the total water resources; the amount of green water resources was 1,232 mm, accounting for 57% of the total water resources. 2) blue water quantity and precipitation were highly positively correlated, and the overall change in green water quantity had been relatively stable. Water quantity of green also showed a positive correlation with precipitation within a certain range, while the green water coefficient and precipitation showed a highly negative correlation; 3) precipitation and other climatic conditions were the decisive factors affecting the amount of blue water resources in the basin, whereas the nature of the underlying surface, such as the vegetation or land use, altitude, and topography, was the main factor affecting the green water volume of the watershed.

Perspectives of human–water co‐evolution of blue–green water resources in subtropical areas

AbstractBlue–green water resources and their transformation play a vital role in crop production and ecosystem services regulation, and their distribution and utilization are affected by human activity, such as policy‐driven green water resources development projects. However, it is unclear how policy‐driven green water resources development projects, such as the Grain for Green Project (GGP) in China, affect eco‐environmental quality and socio‐economic development, that is, human–water co‐evolution. Therefore, considering the GGP in a subtropical ungauged basin in southern China as an example, based on remote sensing hydrological station (RSHS) technology and multisource remote sensing data, this study analyzed the impact of the GGP on human–water co‐evolution from the perspective of blue–green water resources. The results show that: (1) From 2001 to 2020 the GGP transformed more blue water resources into green water resources, resulting in an increase in green water resources of 282.29% compared to that of blue water resources. (2) Due to the initial success of the GGP in 2005, there was a distinct positive correlation between the green water coefficient (GWC) and basin development index (BDI) from 2005 to 2020 (R2 = 0.70, p < 0.05), indicating that the GGP did not cause conflict between the sustainability of socio‐economic development and the health of the ecological environment. (3) In the GGP scenario, in which the cultivated land area maintained 50% of the current decreasing rate, the overall efficiency index maintain a continuously increasing trend at an average rate of 0.001 year−1 from 2021 to 2050, which not only improved the eco‐environmental quality but also met cultivated land demand. This research reveals the role of GGP in promoting the transformation from blue to green water resources, and proves the feasibility of the simultaneous promotion of GGP and socio‐economic development, providing significant insights for the promotion of policy‐driven green water resources development projects and long‐term blue–green water resources planning and management in other countries or regions.

基于SWAT模型的图们江流域蓝绿水资源供需平衡分析

PDF HTML阅读 XML下载 导出引用 引用提醒 基于SWAT模型的图们江流域蓝绿水资源供需平衡分析 DOI: 10.5846/stxb202112173586 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划项目(2019YFC0409104035679); 国家自然科学基金项目(42061042) Analysis of blue and green water scarcity based on SWAT model in the Tumen River Basin Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:随着经济快速发展和工农业各类用水量大幅增加,对河流的开发程度随之加强,流域水资源可持续利用受到不利影响。从蓝绿水视角出发,基于SWAT模型量化了图们江流域2015-2020年不同时间尺度下的蓝绿水资源并探讨了研究区水资源供需平衡情况。结果表明:研究时段内流域蓝绿水资源均具有明显的季节特征,年均蓝绿水资源量为117.16 亿m3,其中蓝水资源量30.14 亿m3,绿水资源量87.02 亿m3,绿水占水资源量的74.27%。以年为尺度,蓝水资源供需评估指数＞1,可利用蓝水资源量基本不能满足其需求量,降水少的年份蓝水资源供需矛盾突出,而绿水资源可以达到供需平衡,其供需评估指数集中在0.1-0.2之间。在月尺度分析中研究区蓝水供需评估指数出现极端值的频率较高,表明该地区蓝水供需不平衡,尤其是可利用蓝水资源一般在每年的7-8月才较为丰富,而蓝水需求用水集中分布于作物生长期,导致蓝水供应与蓝水需求在时间分配上不均衡,且在实际水资源分配中忽略了生态用水;月尺度绿水供需评估指数集中在0.1-0.4之间,有明显的季节变化特征,整体上绿水资源供需平衡安全性较高。 Abstract:With the rapid economic development, the amount of water used for industry and agriculture has significantly increased, most rivers were blind developed and affected the sustainable utilization of water resources. This study quantified water resources from the perspective of blue and green water. The Soil and Water Assessment Tool (SWAT) model was used to simulate the natural runoff in the Tumen River Basin from 2015 to 2020, quantitatively analyzed the change trend of blue water and green water resources at different time scales, and discussed the balance of water supply and demand in the study area. The results showed that the blue and green water resources of the Tumen River Basin presented significantly seasonal characteristics from 2015 to 2020. The average annual amount of blue and green water resources was 11.716 billion m3. The blue and green water resources of the study river basin from 2015 to 2020 were 3.014 billion m3/a and 8.702 billion m3/a, respectively. The study area had different degrees of water scarcities in different time scales. At the annual scale, the supply and demand index of blue water resource was greater than 1, which indicated the supply of blue water basically could not satisfy the demand. The imbalance degree of supply and demand of blue water resource was evident in less precipitation years. In contrast, the balance of supply and demand of green water resource was relatively stable, the index concentrated between 0.1 and 0.2. At the monthly scale, the blue water supply and demand balance index put up high frequency of extreme value, illustrated there was an imbalance appearance between the blue water supply and demand in this region. Especially the blue water availability in annual July to August had the maximum values. However, the blue water withdrawal intensively distributed in the crop growth period, there had a time mismatch between the supply and demand of blue water in the river basin. Moreover, the ecological water was neglected in actual water resources allocation. The monthly green water supply and demand index concentrated between 0.1 and 0.4, with prominently seasonal variation characteristics. Overall, the balance between the supply and demand of green water resource was relatively safe. 参考文献 相似文献 引证文献

Spatio-temporal estimation of green and blue water consumptions and water and land productivity using satellite remote sensing datasets and WA+ framework: A case study of the Mahi Basin, India

The agricultural activities contribute to the largest share of water consumption in the arid and semi-arid basins. In this study, we demonstrate the application of Water Accounting Plus (WA+) for estimation of the green water consumption (ETGreen) and blue water consumption (ETBlue) for assessing the water productivity (WP) and land productivity (LP) to identify the bright-spots and hot-spots at the district administrative unit level for effectively managing the scarce water resources and sustaining food security in a highly non-resilient semi-arid basin of India. The WA+ framework uses satellite remote sensing datasets from different sources for this purpose and we used the data from 2003 to 2020. The long-term average of ETGreen and ETBlue in the Mahi basin is found to be 15.8 km3/year and 12.32 km3/year, respectively. The blue water index (BWI) and green water index (GWI) in the basin vary from 0.282 to 0.598 and 0.40–0.72. We found that the BWI is highest for the districts of Gujarat, whereas, the GWI is highest for the districts of Madhya Pradesh. The long-term average of the LP and WP for both the irrigated and rainfed cereals in the basin is found as 2287.71 kg/ha & 1713.62 kg/ha and 0.721 kg/m³ & 0.483 kg/m³ , respectively from 2003 to 2020. The WP (rainfed) of all the districts of the Gujarat is comparatively lower (varying from 0.34 kg/m³ to 0.5 kg/m³) than the districts of the Madhya Pradesh (varying from 0.59 kg/m3 to 0.70 kg/m³ ) and the Rajasthan (varying from 0.48 kg/m³ to 0.73 kg/m³ ). Based on the results, we found that the Ratlam district of the Madhya Pradesh has both highest LP and WP (irrigated) as 2573.96 kg/ha and 2.14 kg/m3, respectively among all the districts of the Mahi basin, and hence it is classified as the ‘Bright spot-district’. The Anand district is found to have the lowest WP and LP as 0.44 kg/m3 and 2467.51 kg/ha, respectively and hence it is classified as the ‘hot spot-district’. For rainfed cereals, we found that the Neemuch district of Madhya Pradesh has the highest WP and LP as 0.59 kg/m3 and 1948.13 kg /ha, respectively, and the Anand district with the lowest WP as 0.34 kg/m3 and LP of 1572.21 kg/ha, respectively. Therefore, we classified the Neemach district as the ‘Bright spot-district’ and the Anand district as the hot spot- district for rainfed cereals. These findings will help develop sustainable and actionable agricultural water management plans by the policymakers and stakeholders in the basin.

Impacts of precipitation variations on agricultural water scarcity under historical and future climate change

Both blue water and green water contribute to agricultural water scarcity, which is subjected to impacts of precipitation variations in the context of climate change. However, an explicit quantification of the possible effects of precipitation variations on agricultural water scarcity index (AWSI) under historical and future climate is absent. In this study, we applied an integrated AWSI, which incorporates blue water and green water, to estimate agricultural water scarcity in China and to determine the association of AWSI with precipitation variations over the historical (1971–2010) and future (2031–2070) periods. Precipitation variations have substantial effects on changes in AWSI. Especially during extremely dry years with precipitation anomaly lower than −2 standard deviation, changes of AWSI from the multi-year average could be as high as 31%. Future climate change would further intensify AWSI and amplify the effects of precipitation variations, particularly in Inner Mongolia with changes of AWSI over 200%. Southwestern China could also experience expanding agricultural water scarcity under future climate scenarios. Improving irrigation efficiency has potential to alleviate water scarcity by up to 30%. This study provides valuable information for scientists and policy decision makers to cope with the impacts of precipitation variations on AWSI.

Classification analysis of blue and green water quantities for a large-scale watershed of southwest China

Traditional blue water resources assessment and management may not meet the needs of sustainable water resource utilization; ignoring the number of green water resources will underestimate the availability of water resources. To rationally allocate and scientifically manage the limited water resources, it is necessary to divide the rich and poor flow situation of blue water and green water. The MIKE SHE-MIKE HYDRO integrated coupled model was selected and used in the Yalong River basin to ascertain the blue and green water in the hydrological cycle. The model was calibrated by matching simulated discharge against observed streamflow discharge at the Tongziling Station. At the same time, the research analyzed the component of green water and the total amount of blue water or green water on a temporal scale. The set pair analysis (SPA) was introduced to classify blue water and green water, which can not only understand the amount and distribution characteristics of water resources in the Yalong River Basin but also rationally allocate the total of water resources in the basin from the perspective of the regional water cycle. Furthermore, according to the situation of blue water and green water in the basin, the related policies are formulated to realize the efficient utilization of water resources in the Yalong River basin.

Integrating reasonable proportion of blue and green water into land use planning—A new ecological perspective

AbstractUnder the background of shortage of water resources and prominent ecological and environmental problems, the evaluation of blue‐green water resources is a necessary work to meet the ecological water demand and coordinate the distribution of water. Too little or too much blue water or green water will cause social and ecological problems. Land use is not only the main factor affecting blue‐green water but also one of the main ways for human activities to regulate blue‐green water. In this paper, the Soil and Water Assessment Tool (SWAT) model is used to evaluate the multi‐year average current blue water volume of Ziya River Basin from 2005 to 2015, which is 8.193 billion m3, and green water volume is 20.113 billion m3. The spatial distribution of their multi‐year average values shows a trend of gradually increasing from northwest mountainous area to southeast plain area. Considering the changes in population growth, urbanization rate, water quota and other factors, it is estimated that the total available water volume in 2025 is 27.037 billion m3, the blue water volume is 6.853 billion m3 and the green water volume is 20.184 billion m3. By adjusting the land use type, the amount of green water is increased by about 70 million m3, and the proportion of blue‐green water is adjusted from 1:2.5 to 1:2.9. Adjustment scheme 850.88 km2 of steep slope cultivated land with a slope ≥25° around five large reservoirs in the mountainous area will be converted into woodland, and the green water volume will increase by 9 million m3; while increasing the amount of green water without reducing the ecological area, 2,097.16 km2 grassland with a slope ≥40° will be converted into woodland, and the amount of green water will increase by 60 million m3. Integrating the reasonable proportion of blue‐green water into land use planning can provide a new perspective for the balance of blue‐green water resources, the optimal allocation of water intake and land planning.

Spatiotemporal Distribution of Irrigation Water Use Efficiency from the Perspective of Water Footprints in Heilongjiang Province

Water footprints can reflect the sources and utilities of water resources. Introducing the water footprint theory to evaluate irrigation water use efficiency can reflect agricultural water consumption more scientifically and accurately. This study analyzes the variation trends of the blue, green and gray water footprints of grains in different regions of Heilongjiang Province and selects the grain-sowing area, total agricultural machinery power, grain blue water footprint and green water footprints and absolute fertilizer amount as input indexes and the agricultural gross product and gray water footprint of grain as output indexes. A slacks-based measure–data envelopment analysis (SBM-DEA) model is used to estimate the irrigation water use efficiencies of 11 cities in Heilongjiang Province, analyze the corresponding spatiotemporal distribution and further decompose and calculate the irrigation water use efficiencies of the five economically underdeveloped second-level cities. The results suggest that the spatial distribution of the grain water footprint in Heilongjiang Province reflects coexisting areas of excess and scarcity. The irrigation water use efficiency showed a steady and slow downward trend from 2008 to 2018. The irrigation water use efficiency reflected significant spatial differences in Heilongjiang Province, with a pattern of high values in the southwest and low values in the northeast; these differences have gradually narrowed. The average irrigation water use efficiency in Heilongjiang Province was 0.821 and the irrigation water efficiencies of Harbin, Qiqihar and Jixi were at the forefront of the province. Jiamusi, Hegang, Shuangyashan, Yichun, and Mudanjiang are the five cities with below-provincial-average irrigation water use efficiencies. The irrigation water use efficiency of Heilongjiang Province mainly depends on the pure technical efficiency. In the future, technical inputs should be improved on the basis of optimizing the agricultural production layout, focusing on improving the pure technical efficiency. The research results obtained herein can provide a theoretical basis for agricultural water management in Heilongjiang Province.

Impact of land use and land cover dynamics on ecologically-relevant flows and blue-green water resources

Understanding how changes in land use and land cover classes influence the portioning of rainfall into blue and green water resources as well as land use dynamics on ecologically pertinent flows are vital for sustainable water resource management and ecology. Guder catchment, one of the tributaries of the Upper Blue Nile Basin in Ethiopia, was considered for the conduction of ecohydrological modeling using land use land cover maps and the Soil and Water Assessment Tool (SWAT). Cultivation land is expanded while forest and plantation are declined, consequently blue water component increased while the green water component declined in the study catchment. Besides, the decline in low flow specially during months of dry period and increase in high flow during rainy season could have negative consequences for ecology. Therefore, sustainable land and water management at catchment level is essential to protect an ecosystem and for sustainable water resources management. The vital resilience capacity of the ecosystem to accommodate alteration without loss of consistency should be maintained. Change in green water due to land use land cover affects biological functions in terrestrial ecosystem as green water is closely linked with biological functions and rainfed agriculture. The approach applied in the present study to investigate the land use and land cover change impact on blue and green water flows as well as on ecological pertinent streamflows can be simply implemented in other river basin systems.

Volume versus value of crop-related water footprints and virtual water flows: A case study for the Yellow River Basin

Blue water (irrigation water) and green water (rainwater) constitute the indispensable inputs in crop production, and they virtually flow through crop trade. The valuation of water for crops is becoming essential for providing not only guidance in measuring both the biophysical and economic sustainability of agricultural water resources but also crucial information for investors and authorities engaged in water allocations. However, valuation of green water has been severely disregarded. Here, taking the Yellow River Basin as the study case, we show the feasibility of estimating the value of green water for crop production considering the costs in production processes in addition to blue water valuation. Thus, the volume versus value of blue and green water consumed in crop production as well as that of corresponding virtual water (VW) flows related to crop transfers within the basin are comparable. Fourteen major crops in current three typical years and four scenarios for the year 2050 under climate-socio-economic changes are examined. Results show that value of blue water was approximately 3 times that of green water for irrigated crops, whereas at similar level to the value of green water for rain-fed crops. Visible trade-offs between the regional volume and value of water used in crop production and that of the intra-national VW flows exist in terms of magnitude in time and space, as well as the structure by crops. The total volumes of the water footprint (WF), i.e., water consumption, in crop production and VW exports changed little over years, however the corresponding total water values was tripled and seven-folded, respectively, due to apple production expansions. Wheat was the biggest contributor in volume of VW export while apple accounted the most in value of VW export of the basin. The considered scenarios for 2050 suggested that the reduced values of crop-related WF and VW flows were more sensitive than the corresponding water quantity. This study implies the importance of managing the internal trade-offs or mutual effects between water resources and economic returns.

About Suffering

About Suffering Stephanie Douglass Carpenter (bio) "…how it takes place While someone else is eating or opening a window or just walking dully along" – W. H. Auden, "Musée des Beaux Arts" My job is to watch them. Watch them comb their hair and make their beds and get dressed in the morning. Watch those on suicide-watch shower and use the restroom. Watch them eat. We all look forward to meals: They to hamburgers or spaghetti or scrambled eggs or peanut butter and jelly sandwiches, me to the ten or fifteen minutes of calm when they are too focused on their food to act out. There is a special "finger-foods" menu for patients who aren't allowed to use silverware; spoons and forks are the privilege of the meek. Rumor has it that the kitchen used to serve pork chops until a patient tried to stab a staff member with the rib bone. Stand back, my grandmother shouts when frying chicken. From across the kitchen we watch as she uses tongs to lay floured drumsticks and breasts into a froth of boiling oil. If baking she welcomes us close, offers us a spoon or beater to lick. Our matriarch, she presides over every aspect of important meals—Sunday lunches, holiday dinners, milestone celebrations—from preparation to prayer to Tupperware. A few days before my birthday every year, she asks what kind of cake I want. Emerald green, also known as copper acetoarsenite, is concocted by two chemists in a Bavarian lab in 1814. A mix of copper sulfate, acetic acid, and sodium arsenite, the compound evokes the startling blue-green waters of the Mediterranean. Use of the vivid pigment spreads among bakers, who use it to color candies and cake decorations. Watch them go to "school," which is just another locked room in the treatment center, but special, with its alphabet chart and motivational posters. Watch them learn. Watch them get frustrated or bored and run out of the classroom. Watch them watch cartoons (privilege) on Saturday morning. Patients who are noncompliant or aggressive must sit alone at a desk facing the cinderblock wall and write papers about why they are sitting alone at a desk. A good homemade meal lures me back every few weeks. When it is time to leave and return to college, my mom begins crying. She hugs and kisses me several times. Her goodbyes create the impression that this is the last time we will see each other, that I am going to die. [End Page 189] A cake covered in candy flowers with leaves. Sugar dogs reclining in grass. Watch them sit in time-out. Watch them pace back and forth in the quiet room. Watch them visit with family. Watch them play Uno and Monopoly and kickball (all privileges). Watch them pack their belongings and leave for home or another treatment center. Watch them smile. Laugh. Scream. Cry. Rage. I am a teenager when there occurs one of those hometown tragedies that hijacks local attention. It dominates the front page of the newspaper. It leads news broadcasts, the story accompanied by B-roll footage of gray, choppy waters in our reservoir. It bows heads in our congregation as our pastor lifts prayers of comfort and healing for the woman. I try to recall seeing her family in the halls of our large Baptist church where they had been members. I did not know her three sons, who had been several years younger than me. In the immediate aftermath of the tragedy, I closely follow the story, compelled by the lurid eruption of catastrophe. I cannot turn away. My job is not to turn away. My job is to supervise them. I am not their therapist. I am not their friend or their parent, cautions the training guide. I am there to provide direction and structure, to keep them safe and on-task while maintaining the therapeutic milieu. Not a babysitter, and not a guard, but something in between. There are reports of children sickened or killed from green candy. A man dies after eating blancmange adorned with the most vibrant confectionary cucumber and leaves. At times, it feels like watching a...

Integrating Blue and Green Water to Identify Matching Characteristics of Agricultural Water and Land Resources in China

The uneven distribution and spatial mismatch between water and land resources (WLR) limit the utilization efficiency of agricultural water and land resources (AWLR), and then pose a threat to food production. There is a critical need to understand their matching characteristics for strategic resource allocation decisions and management. In this study, a holistic index (RSI) derived from resource equivalency analysis (REA) was developed which contributed to examine the abundance or deficiency of agricultural water and land resources (AWLR) based on the conception of generalized water resources (including blue water and green water). Results indicate that the matching degree of AWLR was the lowest in Northeast China, North China and Gansu in Northwest China, while the highest value was in Xinjiang due to the higher blue water use. In north China, other provinces suffered water scarcity except in Jilin, Liaoning, Henan, while all provinces in south China suffered land scarcity except in Tibet and Jiangsu. Meanwhile, the matching of AWLR was not exactly consistent with the distribution pattern of precipitation. The higher proportion of green water resources was not located in southeast China with rich precipitation; it had to do with water management. Too much or little water resources can result in the increasing of blue water use. The proposed approach can be a powerful instrument to implement public policies and management strategy as an attempt to improve the utilization efficiency and enhance the optimize-allocation of AWLR.