WorldWideScience

Sample records for global water stress

  1. Global monthly water stress: II. Water demand and severity of water

    NARCIS (Netherlands)

    Wada, Y.; Beek, L.P.H. van; Viviroli, D.; Dürr, H.H.; Weingartner, R.; Bierkens, M.F.P.

    2011-01-01

    This paper assesses global water stress at a finer temporal scale compared to conventional assessments. To calculate time series of global water stress at a monthly time scale, global water availability, as obtained from simulations of monthly river discharge from the companion paper, is confronted

  2. Water Stress in Global Transboundary River Basins: Significance of Upstream Water Use on Downstream Stress

    Science.gov (United States)

    Munia, H.; Guillaume, J. H. A.; Mirumachi, N.; Porkka,M.; Wada, Yoshihide; Kummu, M.

    2016-01-01

    Growing population and water demand have increased pressure on water resources in various parts of the globe, including many transboundary river basins. While the impacts of upstream water use on downstream water availability have been analyzed in many of these international river basins, this has not been systematically done at the global scale using coherent and comparable datasets. In this study, we aim to assess the change in downstream water stress due to upstream water use in the world's transboundary river basins. Water stress was first calculated considering only local water use of each sub-basin based on country-basin mesh, then compared with the situation when upstream water use was subtracted from downstream water availability. Wefound that water stress was generally already high when considering only local water use, affecting 0.95-1.44 billion people or 33%-51% of the population in transboundary river basins. After accounting for upstream water use, stress level increased by at least 1 percentage-point for 30-65 sub-basins, affecting 0.29-1.13 billion people. Altogether 288 out of 298 middle-stream and downstream sub-basin areas experienced some change in stress level. Further, we assessed whether there is a link between increased water stress due to upstream water use and the number of conflictive and cooperative events in the transboundary river basins, as captured by two prominent databases. No direct relationship was found. This supports the argument that conflicts and cooperation events originate from a combination of different drivers, among which upstream-induced water stress may play a role. Our findings contribute to better understanding of upstream-downstream dynamics in water stress to help address water allocation problems.

  3. Water stress in global transboundary river basins : Significance of upstream water use on downstream stress

    NARCIS (Netherlands)

    Munia, H.; Guillaume, J. H A; Mirumachi, N.; Porkka, M.; Wada, Y.|info:eu-repo/dai/nl/341387819; Kummu, M.

    2016-01-01

    Growing population and water demand have increased pressure on water resources in various parts of the globe, including many transboundary river basins. While the impacts of upstream water use on downstream water availability have been analysed in many of these international river basins, this has

  4. Modelling global water stress of the recent past: on the relative importance of trends in water demand and climate variability

    NARCIS (Netherlands)

    Wada, Y.; Beek, L.P.H. van; Bierkens, M.F.P.

    2011-01-01

    During the past decades, human water use has more than doubled, yet available freshwater resources are finite. As a result, water scarcity has been prevalent in various regions of the world. Here, we present the first global assessment of past development of water stress considering not only climate

  5. Estimating a Global Hydrological Carrying Capacity Using GRACE Observed Water Stress

    Science.gov (United States)

    An, K.; Reager, J. T.; Famiglietti, J. S.

    2013-12-01

    Global population is expected to reach 9 billion people by the year 2050, causing increased demands for water and potential threats to human security. This study attempts to frame the overpopulation problem through a hydrological resources lens by hypothesizing that observed groundwater trends should be directly attributed to human water consumption. This study analyzes the relationships between available blue water, population, and cropland area on a global scale. Using satellite data from NASA's Gravity Recovery and Climate Experiment (GRACE) along with land surface model data from the Global Land Data Assimilation System (GLDAS), a global groundwater depletion trend is isolated, the validity of which has been verified in many regional studies. By using the inherent distributions of these relationships, we estimate the regional populations that have exceeded their local hydrological carrying capacity. Globally, these populations sum to ~3.5 billion people that are living in presently water-stressed or potentially water-scarce regions, and we estimate total cropland is exceeding a sustainable threshold by about 80 million km^2. Key study areas such as the North China Plain, northwest India, and Mexico City were qualitatively chosen for further analysis of regional water resources and policies, based on our distributions of water stress. These case studies are used to verify the groundwater level changes seen in the GRACE trend . Tfor the many populous, arid regions of the world that have already begun to experience the strains of high water demand.he many populous, arid regions of the world have already begun to experience the strains of high water demand. It will take a global cooperative effort of improving domestic and agricultural use efficiency, and summoning a political will to prioritize environmental issues to adapt to a thirstier planet. Global Groundwater Depletion Trend (Mar 2003-Dec 2011)

  6. Modelling global water stress of the recent past: on the relative importance of trends in water demand and climate variability

    Science.gov (United States)

    Wada, Y.; van Beek, L. P. H.; Bierkens, M. F. P.

    2011-12-01

    During the past decades, human water use has more than doubled, yet available freshwater resources are finite. As a result, water scarcity has been prevalent in various regions of the world. Here, we present the first global assessment of past development of water stress considering not only climate variability but also growing water demand, desalinated water use and non-renewable groundwater abstraction over the period 1960-2001 at a spatial resolution of 0.5°. Agricultural water demand is estimated based on past extents of irrigated areas and livestock densities. We approximate past economic development based on GDP, energy and household consumption and electricity production, which are subsequently used together with population numbers to estimate industrial and domestic water demand. Climate variability is expressed by simulated blue water availability defined by freshwater in rivers, lakes, wetlands and reservoirs by means of the global hydrological model PCR-GLOBWB. We thus define blue water stress by comparing blue water availability with corresponding net total blue water demand by means of the commonly used, Water Scarcity Index. The results show a drastic increase in the global population living under water-stressed conditions (i.e. moderate to high water stress) due to growing water demand, primarily for irrigation, which has more than doubled from 1708/818 to 3708/1832 km3 yr-1 (gross/net) over the period 1960-2000. We estimate that 800 million people or 27% of the global population were living under water-stressed conditions for 1960. This number is eventually increased to 2.6 billion or 43% for 2000. Our results indicate that increased water demand is a decisive factor for heightened water stress in various regions such as India and North China, enhancing the intensity of water stress up to 200%, while climate variability is often a main determinant of extreme events. However, our results also suggest that in several emerging and developing economies

  7. Modelling global water stress of the recent past: on the relative importance of trends in water demand and climate variability

    Science.gov (United States)

    Wada, Y.; van Beek, L. P. H.; Bierkens, M. F. P.

    2011-08-01

    During the past decades, human water use more than doubled, yet available freshwater resources are finite. As a result, water scarcity has been prevalent in various regions of the world. Here, we present the first global assessment of past development of water scarcity considering not only climate variability but also growing water demand, desalinated water use and non-renewable groundwater abstraction over the period 1960-2001 at a spatial resolution of 0.5°. Agricultural water demand is estimated based on past extents of irrigated areas and livestock densities. We approximate past economic development based on GDP, energy and household consumption and electricity production, which is subsequently used together with population numbers to estimate industrial and domestic water demand. Climate variability is expressed by simulated blue water availability defined by freshwater in rivers, lakes and reservoirs by means of the global hydrological model PCR-GLOBWB. The results show a drastic increase in the global population living under water-stressed conditions (i.e., moderate to high water stress) due to the growing water demand, primarily for irrigation, which more than doubled from 1708/818 to 3708/1832 km3 yr-1 (gross/net) over the period 1960-2000. We estimate that 800 million people or 27 % of the global population were under water-stressed conditions for 1960. This number increased to 2.6 billion or 43 % for 2000. Our results indicate that increased water demand is the decisive factor for the heightened water stress, enhancing the intensity of water stress up to 200 %, while climate variability is often the main determinant of onsets for extreme events, i.e. major droughts. However, our results also suggest that in several emerging and developing economies (e.g., India, Turkey, Romania and Cuba) some of the past observed droughts were anthropogenically driven due to increased water demand rather than being climate-induced. In those countries, it can be seen

  8. Evaluation of water stress and groundwater storage using a global hydrological model

    Science.gov (United States)

    Shiojiri, D.; Tanaka, K.; Tanaka, S.

    2017-12-01

    United Nations reported the number of people will reach 9.7 billion in 2050, and this rapid growth of population will increase water use. To prevent global water shortage, it is important to identify the problematic areas in order to maintain water resources sustainability. Moreover, groundwater availability is decreasing in some areas due to excessive groundwater extraction compared to the groundwater recharge capacity. The development of a hydrological model that can simulate the current status of the world's water resources represents an important tool to achieve sustainable water resources management. In this study, a global hydrological simulation is conducted at a 20km spatial resolution using the land surface model SiBUC, which is coupled to the river routing model HydroBEAM. In the river routing model, we evaluate water stress by comparing the excess of water demand with the river water demand. Areas with high water stress are seen in United States, India, and east part of China; however, for the case of Africa the overall water stress is zero. This could be because rain-fed agriculture is the norm in Africa and thus irrigation water demand is low, which affects water stress index. Sustainability of groundwater resources is also evaluated in the river routing model by setting a virtual groundwater tank. When the amount of groundwater withdrawal constantly exceeds groundwater recharge, the volume in the tank falls below zero and the area is regarded as unsustainable in terms of groundwater usage. Such areas are mostly seen in central United States, northeast China, the region between northwest India and Pakistan. In the simulation with SiBUC, the amount of groundwater recharge is assumed as the proportion of water that flows from the second to the third soil layer. This proportion will be estimated by comparing monthly variations of terrestrial water storage (TWS) derived from the observations of the GRACE satellite with the simulated TWS variations. From

  9. Adapting the law of water management to global climate change and other hydropolitical stresses

    International Nuclear Information System (INIS)

    Dellapenna, J.W.

    2002-01-01

    There is little reason for doubt today that the planet is undergoing significant and even alarming climate change. One study found that after nearly a millennium of a slow but steady cooling trend, the twentieth century has seen a dramatic and dramatically accelerating upsurge in average global temperatures. (Stevens, 1999b) Farmers are already experiencing measurably longer growing seasons across the Northern Hemisphere. (Stevens, 1999a) With growing evidence of the melting of the polar ice caps, there is little room left to argue that climate change is an illusion. (Stevens, 1999c) These changes - whether the result of human agency or otherwise - inevitably will have vast impact on the precipitation patterns around the world. The last time the planet underwent a global climate change of a comparable scale was the end of the last Ice Age - and that change was spread out over several thousand years compared to the present change that appears to be occurring over a period of only a few centuries. The change at the end of the last ice age - only some 12,000 years ago or so - turned the Middle East from a region of plentiful occupied by a relatively dense human population of hunters and gatherers to the largest dry region on earth. Facing the prospect of imminent starvation, presumably most of people in the region chose to migrate, yet some found a way to adapt without migrating. (Issar, 1990) Apparently, a few of the women (who would have been responsible for gathering and caring for seeds and berries while the men were off hunting) discovered that they could plant some of the seeds they gathered and thereby multiply the yield sufficiently to sustain their communities and even support an increase in population. (Jacobs, 1969) After a millennium or more, the farmers realized that they could dig ditches from the rivers out onto the remarkably flat plains of the land between or near the Euphrates and Tigris Rivers to bring water out to the now deep soils. This

  10. Adapting the law of water management to global climate change and other hydropolitical stresses

    Energy Technology Data Exchange (ETDEWEB)

    Dellapenna, J.W. [Villanova Univ. School of Law, Vallanova, PA (United States)]. E-mail: dellapen@law.vill.edu

    2002-06-15

    There is little reason for doubt today that the planet is undergoing significant and even alarming climate change. One study found that after nearly a millennium of a slow but steady cooling trend, the twentieth century has seen a dramatic and dramatically accelerating upsurge in average global temperatures. (Stevens, 1999b) Farmers are already experiencing measurably longer growing seasons across the Northern Hemisphere. (Stevens, 1999a) With growing evidence of the melting of the polar ice caps, there is little room left to argue that climate change is an illusion. (Stevens, 1999c) These changes - whether the result of human agency or otherwise - inevitably will have vast impact on the precipitation patterns around the world. The last time the planet underwent a global climate change of a comparable scale was the end of the last Ice Age - and that change was spread out over several thousand years compared to the present change that appears to be occurring over a period of only a few centuries. The change at the end of the last ice age - only some 12,000 years ago or so - turned the Middle East from a region of plentiful occupied by a relatively dense human population of hunters and gatherers to the largest dry region on earth. Facing the prospect of imminent starvation, presumably most of people in the region chose to migrate, yet some found a way to adapt without migrating. (Issar, 1990) Apparently, a few of the women (who would have been responsible for gathering and caring for seeds and berries while the men were off hunting) discovered that they could plant some of the seeds they gathered and thereby multiply the yield sufficiently to sustain their communities and even support an increase in population. (Jacobs, 1969) After a millennium or more, the farmers realized that they could dig ditches from the rivers out onto the remarkably flat plains of the land between or near the Euphrates and Tigris Rivers to bring water out to the now deep soils. This

  11. Global water cycle

    Science.gov (United States)

    Robertson, Franklin; Goodman, Steven J.; Christy, John R.; Fitzjarrald, Daniel E.; Chou, Shi-Hung; Crosson, William; Wang, Shouping; Ramirez, Jorge

    1993-01-01

    This research is the MSFC component of a joint MSFC/Pennsylvania State University Eos Interdisciplinary Investigation on the global water cycle extension across the earth sciences. The primary long-term objective of this investigation is to determine the scope and interactions of the global water cycle with all components of the Earth system and to understand how it stimulates and regulates change on both global and regional scales. Significant accomplishments in the past year are presented and include the following: (1) water vapor variability; (2) multi-phase water analysis; (3) global modeling; and (4) optimal precipitation and stream flow analysis and hydrologic processes.

  12. Water vs. carbon: An evaluation of SMAP soil moisture and OCO-2 solar-induced fluorescence to characterize global plant stress

    Science.gov (United States)

    Purdy, A. J.; Fisher, J.; Goulden, M.; Randerson, J. T.; Famiglietti, J. S.

    2017-12-01

    Plants link the carbon and water cycles through photosynthesis and evapotranspiration (ET). When plants take in CO2 for photosynthesis, water evaporates to the atmosphere. This exchange of carbon and water is sensitive to a number of environmental variables including: soil water availability, temperature, atmospheric water vapor, and radiation. When the atmospheric demand for water is high, plants avoid hydraulic failure by regulating the amount of water exiting leaves at the expense of inhibiting carbon uptake. Over time, stress caused by this response limits plant growth and can even result in death by carbon starvation. With increasing atmospheric demand for water, impending expansion of arid regions, and more frequent droughts, understanding how vegetation responds to regulate photosynthesis and ET is important to quantify potential feedbacks between the carbon and water cycles. Despite its importance, to what extent plants respond to stressful conditions is an open science question. An important step forward is to characterize the dominant controls in these stress events and identify geographic areas that are vulnerable to climate change. The 2015-2016 El Nino and subsequent 2016-2017 La Nina transition provides an opportunity to quantify the extent and magnitude of vegetation regulation of these carbon and water variables in response to changes in environmental conditions. We present results from a space-based analysis using global observations of solar induced fluorescence (SIF) from the Orbiting Carbon Observatory-2 (OCO-2), soil moisture from Soil Moisture Active Passive (SMAP), and two widely used ET models (PT-JPL and MOD-16) to characterize the dominant controls on gross primary production and ET.

  13. Saving water through global trade

    NARCIS (Netherlands)

    Chapagain, Ashok; Hoekstra, Arjen Ysbert; Savenije, H.H.G.

    2005-01-01

    Many nations save domestic water resources by importing water-intensive products and exporting commodities that are less water intensive. National water saving through the import of a product can imply saving water at a global level if the flow is from sites with high to sites with low water

  14. Global Geopotential Energy & Stress Field

    DEFF Research Database (Denmark)

    Schiffer, Christian; Nielsen, S.B.

    of the oceanic lithosphere. An entire modelling of the shallow Geopotential Energy is hereby approached, not taking into account possible deeper signals but all lithospheric signals for the subsequent stress calculation. Therefore a global lithospheric density model is necessary to calculate the corresponding...... response to Geopotential Energy and the Geoid. A linearized inverse method fits a lithospheric reference model to reproduce measured data sets, such as topography and surface heat flow, while assuming isostasy and solving the steady state heat equation. A FEM code solves the equations of equilibrium...

  15. Are water markets globally applicable?

    Science.gov (United States)

    Endo, Takahiro; Kakinuma, Kaoru; Yoshikawa, Sayaka; Kanae, Shinjiro

    2018-03-01

    Water scarcity is a global concern that necessitates a global perspective, but it is also the product of multiple regional issues that require regional solutions. Water markets constitute a regionally applicable non-structural measure to counter water scarcity that has received the attention of academics and policy-makers, but there is no global view on their applicability. We present the global distribution of potential nations and states where water markets could be instituted in a legal sense, by investigating 296 water laws internationally, with special reference to a minimum set of key rules: legalization of water reallocation, the separation of water rights and landownership, and the modification of the cancellation rule for non-use. We also suggest two additional globally distributed prerequisites and policy implications: the predictability of the available water before irrigation periods and public control of groundwater pumping throughout its jurisdiction.

  16. Water Stress Projection Modeling

    Science.gov (United States)

    2016-09-01

    water consumption stress in coming decades is electricity generation in two surrounding counties, El Paso and Doña Ana, which are expected to...better able to predict and prepare for a changing climate. Army installations will be affected by climate change. It behooves the Army to understand...stationing analysis, the resources ex- amined were: a. Training land b. Energy ( electricity and natural gas) c. Water and wastewater treatment and solid

  17. Greening the global water system

    Science.gov (United States)

    Hoff, H.; Falkenmark, M.; Gerten, D.; Gordon, L.; Karlberg, L.; Rockström, J.

    2010-04-01

    SummaryRecent developments of global models and data sets enable a new, spatially explicit and process-based assessment of green and blue water in food production and trade. An initial intercomparison of a range of different (hydrological, vegetation, crop, water resources and economic) models, confirms that green water use in global crop production is about 4-5 times greater than consumptive blue water use. Hence, the full green-to-blue spectrum of agricultural water management options needs to be used when tackling the increasing water gap in food production. The different models calculate considerable potentials for complementing the conventional approach of adding irrigation, with measures to increase water productivity, such as rainwater harvesting, supplementary irrigation, vapour shift and soil and nutrient management. Several models highlight Africa, in particular sub-Saharan Africa, as a key region for improving water productivity in agriculture, by implementing these measures. Virtual water trade, mostly based on green water, helps to close the water gap in a number of countries. It is likely to become even more important in the future, when inequities in water availability are projected to grow, due to climate, population and other drivers of change. Further model developments and a rigorous green-blue water model intercomparison are proposed, to improve simulations at global and regional scale and to enable tradeoff analyses for the different adaptation options.

  18. Underground water stress release models

    Science.gov (United States)

    Li, Yong; Dang, Shenjun; Lü, Shaochuan

    2011-08-01

    The accumulation of tectonic stress may cause earthquakes at some epochs. However, in most cases, it leads to crustal deformations. Underground water level is a sensitive indication of the crustal deformations. We incorporate the information of the underground water level into the stress release models (SRM), and obtain the underground water stress release model (USRM). We apply USRM to the earthquakes occurred at Tangshan region. The analysis shows that the underground water stress release model outperforms both Poisson model and stress release model. Monte Carlo simulation shows that the simulated seismicity by USRM is very close to the real seismicity.

  19. Global water resources: vulnerability from climate change and population growth.

    Science.gov (United States)

    Vörösmarty, C J; Green, P; Salisbury, J; Lammers, R B

    2000-07-14

    The future adequacy of freshwater resources is difficult to assess, owing to a complex and rapidly changing geography of water supply and use. Numerical experiments combining climate model outputs, water budgets, and socioeconomic information along digitized river networks demonstrate that (i) a large proportion of the world's population is currently experiencing water stress and (ii) rising water demands greatly outweigh greenhouse warming in defining the state of global water systems to 2025. Consideration of direct human impacts on global water supply remains a poorly articulated but potentially important facet of the larger global change question.

  20. An Integrated Analysis of Changes in Water Stress in Europe

    DEFF Research Database (Denmark)

    Henrichs, T.; Lehner, B.; Alcamo, J.

    2002-01-01

    Future changes in water availability with climate change and changes in water use due to socio-economic development are to occur in parallel. In an integrated analysis we bring together these aspects of global change in a consistent manner, and analyse the water stress situation in Europe. We find...... that today high water stress exists in one-fifth of European river basin area. Under a scenario projection, increases in water use throughout Eastern Europe are accompanied by decreases in water availability in most of Southern Europe--combining these trends leads to a marked increase in water stress...

  1. The Global Politics of Water Grabbing

    NARCIS (Netherlands)

    Franco, J.; Mehta, L.; Veldwisch, G.J.A.

    2013-01-01

    The contestation and appropriation of water is not new, but it has been highlighted by recent global debates on land grabbing. Water grabbing takes place in a field that is locally and globally plural-legal. Formal law has been fostering both land and water grabs but formal water and land management

  2. The global politics of water grabbing

    NARCIS (Netherlands)

    Franco, Jennifer; Mehta, Lyla; Veldwisch, Gert Jan

    2016-01-01

    The contestation and appropriation of water is not new, but it has been highlighted by recent global debates on land grabbing. Water grabbing takes place in a field that is locally and globally plural-legal. Formal law has been fostering both land and water grabs but formal water and land

  3. Global water governance. Conceptual design of global institutional arrangements

    NARCIS (Netherlands)

    Verkerk, M.P.; Gerbens-Leenes, Winnie; Hoekstra, Arjen Ysbert

    2008-01-01

    This study builds upon the explorative study of Hoekstra (2006), who puts forward an argument for coordination at the global level in ‘water governance’. Water governance is understood here in the broad sense as ‘the way people use and maintain water resources’. One of the factors that give water

  4. Global Water Issues and Insights

    OpenAIRE

    Grafton, Quentin R.; Wyrwoll, Paul; White , Chris; Allendes, David

    2014-01-01

    This book brings together some of the world’s leading water researchers with an especially written collection of chapters on: water economics; transboundary water; water and development; water and energy; and water concepts.

  5. Sustainable water future with global implications: everyone's responsibility.

    Science.gov (United States)

    Kuylenstierna, J L; Bjorklund, G; Najlis, P

    1997-01-01

    The current use and management of freshwater is not sustainable in many countries and regions of the world. If current trends are maintained, about two-thirds of the world's population will face moderate to severe water stress by 2025 compared to one-third at present. This water stress will hamper economic and social development unless action is taken to deal with the emerging problems. The Comprehensive Assessment of the Freshwater Resources of the World, prepared by the UN and the Stockholm Environment Institute, calls for immediate action to prevent further deterioration of freshwater resources. Although most problems related to water quantity and quality require national and regional solutions, only a global commitment can achieve the necessary agreement on principles, as well as financial means to attain sustainability. Due to the central and integrated role played by water in human activities, any measures taken need to incorporate a wide range of social, ecological and economic factors and needs. The Assessment thus addresses the many issues related to freshwater use, such as integrated land and water management at the watershed level, global food security, water supply and sanitation, ecosystem requirements, pollution, strengthening of major groups, and national water resource assessment capabilities and monitoring networks. Governments are urged to work towards a consensus regarding global principles and guidelines for integrated water management, and towards their implementation in local and regional water management situations. The alternative development options available to countries facing water stress, or the risk thereof, needs to be considered in all aspects of development planning.

  6. Plant responses to water stress

    Science.gov (United States)

    Kar, Rup Kumar

    2011-01-01

    Terrestrial plants most often encounter drought stress because of erratic rainfall which has become compounded due to present climatic changes.Responses of plants to water stress may be assigned as either injurious change or tolerance index. One of the primary and cardinal changes in response to drought stress is the generation of reactive oxygen species (ROS), which is being considered as the cause of cellular damage. However, recently a signaling role of such ROS in triggering the ROS scavenging system that may confer protection or tolerance against stress is emerging. Such scavenging system consists of antioxidant enzymes like SOD, catalase and peroxidases, and antioxidant compounds like ascorbate, reduced glutathione; a balance between ROS generation and scavenging ultimately determines the oxidative load. As revealed in case of defence against pathogen, signaling via ROS is initiated by NADPH oxidase-catalyzed superoxide generation in the apoplastic space (cell wall) followed by conversion to hydrogen peroxide by the activity of cell wall-localized SOD. Wall peroxidase may also play role in ROS generation for signaling. Hydrogen peroxide may use Ca2+ and MAPK pathway as downstream signaling cascade. Plant hormones associated with stress responses like ABA and ethylene play their role possibly via a cross talk with ROS towards stress tolerance, thus projecting a dual role of ROS under drought stress. PMID:22057331

  7. Agricultural Water Use under Global Change

    Science.gov (United States)

    Zhu, T.; Ringler, C.; Rosegrant, M. W.

    2008-12-01

    Irrigation is by far the single largest user of water in the world and is projected to remain so in the foreseeable future. Globally, irrigated agricultural land comprises less than twenty percent of total cropland but produces about forty percent of the world's food. Increasing world population will require more food and this will lead to more irrigation in many areas. As demands increase and water becomes an increasingly scarce resource, agriculture's competition for water with other economic sectors will be intensified. This water picture is expected to become even more complex as climate change will impose substantial impacts on water availability and demand, in particular for agriculture. To better understand future water demand and supply under global change, including changes in demographic, economic and technological dimensions, the water simulation module of IMPACT, a global water and food projection model developed at the International Food Policy Research Institute, is used to analyze future water demand and supply in agricultural and several non-agricultural sectors using downscaled GCM scenarios, based on water availability simulation done with a recently developed semi-distributed global hydrological model. Risk analysis is conducted to identify countries and regions where future water supply reliability for irrigation is low, and food security may be threatened in the presence of climate change. Gridded shadow values of irrigation water are derived for global cropland based on an optimization framework, and they are used to illustrate potential irrigation development by incorporating gridded water availability and existing global map of irrigation areas.

  8. Infectious Disinfection: "Exploring Global Water Quality"

    Science.gov (United States)

    Mahaya, Evans; Tippins, Deborah J.; Mueller, Michael P.; Thomson, Norman

    2009-01-01

    Learning about the water situation in other regions of the world and the devastating effects of floods on drinking water helps students study science while learning about global water quality. This article provides science activities focused on developing cultural awareness and understanding how local water resources are integrally linked to the…

  9. Aqueduct: a methodology to measure and communicate global water risks

    Science.gov (United States)

    Gassert, Francis; Reig, Paul

    2013-04-01

    The Aqueduct Water Risk Atlas (Aqueduct) is a publicly available, global database and interactive tool that maps indicators of water related risks for decision makers worldwide. Aqueduct makes use of the latest geo-statistical modeling techniques to compute a composite index and translate the most recently available hydrological data into practical information on water related risks for companies, investors, and governments alike. Twelve global indicators are grouped into a Water Risk Framework designed in response to the growing concerns from private sector actors around water scarcity, water quality, climate change, and increasing demand for freshwater. The Aqueduct framework organizes indicators into three categories of risk that bring together multiple dimensions of water related risk into comprehensive aggregated scores and includes indicators of water stress, variability in supply, storage, flood, drought, groundwater, water quality and social conflict, addressing both spatial and temporal variation in water hazards. Indicators are selected based on relevance to water users, availability and robustness of global data sources, and expert consultation, and are collected from existing datasets or derived from a Global Land Data Assimilation System (GLDAS) based integrated water balance model. Indicators are normalized using a threshold approach, and composite scores are computed using a linear aggregation scheme that allows for dynamic weighting to capture users' unique exposure to water hazards. By providing consistent scores across the globe, the Aqueduct Water Risk Atlas enables rapid comparison across diverse aspects of water risk. Companies can use this information to prioritize actions, investors to leverage financial interest to improve water management, and governments to engage with the private sector to seek solutions for more equitable and sustainable water governance. The Aqueduct Water Risk Atlas enables practical applications of scientific data

  10. Drivers And Uncertainties Of Increasing Global Water Scarcity

    Science.gov (United States)

    Scherer, L.; Pfister, S.

    2015-12-01

    Water scarcity threatens ecosystems and human health and hampers economic development. It generally depends on the ratio of water consumption to availability. We calculated global, spatially explicit water stress indices (WSIs) which describe the vulnerability to additional water consumption on a scale from 0 (low) to 1 (high) and compare them for the decades 1981-1990 and 2001-2010. Input data are obtained from a multi-model ensemble at a resolution of 0.5 degrees. The variability among the models was used to run 1000 Monte Carlo simulations (latin hypercube sampling) and to subsequently estimate uncertainties of the WSIs. Globally, a trend of increasing water scarcity can be observed, however, uncertainties are large. The probability that this trend is actually occurring is as low as 53%. The increase in WSIs is rather driven by higher water use than lower water availability. Water availability is only 40% likely to decrease whereas water consumption is 67% likely to increase. Independent from the trend, we are already living under water scarce conditions, which is reflected in a consumption-weighted average of monthly WSIs of 0.51 in the recent decade. Its coefficient of variation points with 0.8 to the high uncertainties entailed, which might still hide poor model performance where all models consistently over- or underestimate water availability or use. Especially in arid areas, models generally overestimate availability. Although we do not traverse the planetary boundary of freshwater use as global water availability is sufficient, local water scarcity might be high. Therefore the regionalized assessment of WSIs under uncertainty helps to focus on specific regions to optimise water consumption. These global results can also help to raise awareness of water scarcity, and to suggest relevant measures such as more water efficient technologies to international companies, which have to deal with complex and distributed supply chains (e.g. in food production).

  11. Establishing the Global Fresh Water Sensor Web

    Science.gov (United States)

    Hildebrand, Peter H.

    2005-01-01

    This paper presents an approach to measuring the major components of the water cycle from space using the concept of a sensor-web of satellites that are linked to a data assimilation system. This topic is of increasing importance, due to the need for fresh water to support the growing human population, coupled with climate variability and change. The net effect is that water is an increasingly valuable commodity. The distribution of fresh water is highly uneven over the Earth, with both strong latitudinal distributions due to the atmospheric general circulation, and even larger variability due to landforms and the interaction of land with global weather systems. The annual global fresh water budget is largely a balance between evaporation, atmospheric transport, precipitation and runoff. Although the available volume of fresh water on land is small, the short residence time of water in these fresh water reservoirs causes the flux of fresh water - through evaporation, atmospheric transport, precipitation and runoff - to be large. With a total atmospheric water store of approx. 13 x 10(exp 12)cu m, and an annual flux of approx. 460 x 10(exp 12)cu m/y, the mean atmospheric residence time of water is approx. 10 days. River residence times are similar, biological are approx. 1 week, soil moisture is approx. 2 months, and lakes and aquifers are highly variable, extending from weeks to years. The hypothesized potential for redistribution and acceleration of the global hydrological cycle is therefore of concern. This hypothesized speed-up - thought to be associated with global warming - adds to the pressure placed upon water resources by the burgeoning human population, the variability of weather and climate, and concerns about anthropogenic impacts on global fresh water availability.

  12. Systems responses to progressive water stress in durum wheat.

    Directory of Open Access Journals (Sweden)

    Dimah Z Habash

    Full Text Available Durum wheat is susceptible to terminal drought which can greatly decrease grain yield. Breeding to improve crop yield is hampered by inadequate knowledge of how the physiological and metabolic changes caused by drought are related to gene expression. To gain better insight into mechanisms defining resistance to water stress we studied the physiological and transcriptome responses of three durum breeding lines varying for yield stability under drought. Parents of a mapping population (Lahn x Cham1 and a recombinant inbred line (RIL2219 showed lowered flag leaf relative water content, water potential and photosynthesis when subjected to controlled water stress time transient experiments over a six-day period. RIL2219 lost less water and showed constitutively higher stomatal conductance, photosynthesis, transpiration, abscisic acid content and enhanced osmotic adjustment at equivalent leaf water compared to parents, thus defining a physiological strategy for high yield stability under water stress. Parallel analysis of the flag leaf transcriptome under stress uncovered global trends of early changes in regulatory pathways, reconfiguration of primary and secondary metabolism and lowered expression of transcripts in photosynthesis in all three lines. Differences in the number of genes, magnitude and profile of their expression response were also established amongst the lines with a high number belonging to regulatory pathways. In addition, we documented a large number of genes showing constitutive differences in leaf transcript expression between the genotypes at control non-stress conditions. Principal Coordinates Analysis uncovered a high level of structure in the transcriptome response to water stress in each wheat line suggesting genome-wide co-ordination of transcription. Utilising a systems-based approach of analysing the integrated wheat's response to water stress, in terms of biological robustness theory, the findings suggest that each durum

  13. Global climate change and California's water resources

    International Nuclear Information System (INIS)

    Vaux, H.J. Jr.

    1991-01-01

    This chapter records the deliberations of a group of California water experts about answers to these and other questions related to the impact of global warming on California's water resources. For the most part, those participating in the deliberations believe that the current state of scientific knowledge about global warming and its impacts on water resources is insufficient to permit hard distinctions to be made between short- and long-term changes. consequently, the ideas discussed here are based on a number of assumptions about specific climatic manifestations of global warming in California, as described earlier in this volume. Ultimately, however, effective public responses to forestall the potentially costly impacts of global climate change will probably depend upon the credible validation of the prospects of global climate warming. This chapter contains several sections. First, the likely effects of global warming on California's water resources and water-supply systems are identified and analyzed. Second, possible responses to mitigate these effects are enumerated and discussed. Third, the major policy issues are identified. A final section lists recommendations for action and major needs for information

  14. Challenges in global ballast water management

    International Nuclear Information System (INIS)

    Endresen, Oyvind; Lee Behrens, Hanna; Brynestad, Sigrid; Bjoern Andersen, Aage; Skjong, Rolf

    2004-01-01

    Ballast water management is a complex issue raising the challenge of merging international regulations, ship's specific configurations along with ecological conservation. This complexity is illustrated in this paper by considering ballast water volume, discharge frequency, ship safety and operational issues aligned with regional characteristics to address ecological risk for selected routes. A re-estimation of ballast water volumes gives a global annual level of 3500 Mton. Global ballast water volume discharged into open sea originating from ballast water exchange operations is estimated to approximately 2800 Mton. Risk based decision support systems coupled to databases for different ports and invasive species characteristics and distributions can allow for differentiated treatment levels while maintaining low risk levels. On certain routes, the risk is estimated to be unacceptable and some kind of ballast water treatment or management should be applied

  15. Observing the Global Water Cycle from Space

    Science.gov (United States)

    Hildebrand, P. H.

    2004-01-01

    This paper presents an approach to measuring all major components of the water cycle from space. Key elements of the global water cycle are discussed in terms of the storage of water-in the ocean, air, cloud and precipitation, in soil, ground water, snow and ice, and in lakes and rivers, and in terms of the global fluxes of water between these reservoirs. Approaches to measuring or otherwise evaluating the global water cycle are presented, and the limitations on known accuracy for many components of the water cycle are discussed, as are the characteristic spatial and temporal scales of the different water cycle components. Using these observational requirements for a global water cycle observing system, an approach to measuring the global water cycle from space is developed. The capabilities of various active and passive microwave instruments are discussed, as is the potential of supporting measurements from other sources. Examples of space observational systems, including TRMM/GPM precipitation measurement, cloud radars, soil moisture, sea surface salinity, temperature and humidity profiling, other measurement approaches and assimilation of the microwave and other data into interpretative computer models are discussed to develop the observational possibilities. The selection of orbits is then addressed, for orbit selection and antenna size/beamwidth considerations determine the sampling characteristics for satellite measurement systems. These considerations dictate a particular set of measurement possibilities, which are then matched to the observational sampling requirements based on the science. The results define a network of satellite instrumentation systems, many in low Earth orbit, a few in geostationary orbit, and all tied together through a sampling network that feeds the observations into a data-assimilative computer model.

  16. Growing water scarcity in agriculture: future challenge to global water security.

    Science.gov (United States)

    Falkenmark, Malin

    2013-11-13

    As water is an essential component of the planetary life support system, water deficiency constitutes an insecurity that has to be overcome in the process of socio-economic development. The paper analyses the origin and appearance of blue as well as green water scarcity on different scales and with particular focus on risks to food production and water supply for municipalities and industry. It analyses water scarcity originating from both climatic phenomena and water partitioning disturbances on different scales: crop field, country level and the global circulation system. The implications by 2050 of water scarcity in terms of potential country-level water deficits for food self-reliance are analysed, and the compensating dependence on trade in virtual water for almost half the world population is noted. Planetary-scale conditions for sustainability of the global water circulation system are discussed in terms of a recently proposed Planetary Freshwater Boundary, and the consumptive water use reserve left to be shared between water requirements for global food production, fuelwood production and carbon sequestration is discussed. Finally, the importance of a paradigm shift in the further conceptual development of water security is stressed, so that adequate attention is paid to water's fundamental role in both natural and socio-economic systems.

  17. Trade in water and commodities as adaptations to global change

    Science.gov (United States)

    Lammers, R. B.; Hertel, T. W.; Prousevitch, A.; Baldos, U. L. C.; Frolking, S. E.; Liu, J.; Grogan, D. S.

    2015-12-01

    The human capacity for altering the water cycle has been well documented and given the expected change due to population, income growth, biofuels, climate, and associated land use change, there remains great uncertainty in both the degree of increased pressure on land and water resources and in our ability to adapt to these changes. Alleviating regional shortages in water supply can be carried out in a spatial hierarchy through i) direct trade of water between all regions, ii) development of infrastructure to improve water availability within regions (e.g. impounding rivers), iii) via inter-basin hydrological transfer between neighboring regions and, iv) via virtual water trade. These adaptation strategies can be managed via market trade in water and commodities to identify those strategies most likely to be adopted. This work combines the physically-based University of New Hampshire Water Balance Model (WBM) with the macro-scale Purdue University Simplified International Model of agricultural Prices Land use and the Environment (SIMPLE) to explore the interaction of supply and demand for fresh water globally. In this work we use a newly developed grid cell-based version of SIMPLE to achieve a more direct connection between the two modeling paradigms of physically-based models with optimization-driven approaches characteristic of economic models. We explore questions related to the global and regional impact of water scarcity and water surplus on the ability of regions to adapt to future change. Allowing for a variety of adaptation strategies such as direct trade of water and expanding the built water infrastructure, as well as indirect trade in commodities, will reduce overall global water stress and, in some regions, significantly reduce their vulnerability to these future changes.

  18. Groundwater development stress: Global-scale indices compared to regional modeling

    Science.gov (United States)

    Alley, William; Clark, Brian R.; Ely, Matt; Faunt, Claudia

    2018-01-01

    The increased availability of global datasets and technologies such as global hydrologic models and the Gravity Recovery and Climate Experiment (GRACE) satellites have resulted in a growing number of global-scale assessments of water availability using simple indices of water stress. Developed initially for surface water, such indices are increasingly used to evaluate global groundwater resources. We compare indices of groundwater development stress for three major agricultural areas of the United States to information available from regional water budgets developed from detailed groundwater modeling. These comparisons illustrate the potential value of regional-scale analyses to supplement global hydrological models and GRACE analyses of groundwater depletion. Regional-scale analyses allow assessments of water stress that better account for scale effects, the dynamics of groundwater flow systems, the complexities of irrigated agricultural systems, and the laws, regulations, engineering, and socioeconomic factors that govern groundwater use. Strategic use of regional-scale models with global-scale analyses would greatly enhance knowledge of the global groundwater depletion problem.

  19. The global collaboration on traumatic stress

    NARCIS (Netherlands)

    Schnyder, Ulrich; Schäfer, Ingo; Aakvaag, Helene F.; Ajdukovic, Dean; Bakker, Anne; Bisson, Jonathan I.; Brewer, Douglas; Cloitre, Marylène; Dyb, Grete A.; Frewen, Paul; Lanza, Juliana; Le Brocque, Robyne; Lueger-Schuster, Brigitte; Mwiti, Gladys K.; Oe, Misari; Rosner, Rita; Schellong, Julia; Shigemura, Jun; Wu, Kitty; Olff, Miranda

    2017-01-01

    Trauma is a global issue. The great majority of the global burden of disease arising from mental health conditions occurs in low- and middle-income countries (LMICs), among populations in political, economic, and/or cultural transition and those struck by forced migration. These mental health

  20. Global Changes of the Water Cycle Intensity

    Science.gov (United States)

    Bosilovich, Michael G.; Schubert, Siegfried D.; Walker, Gregory K.

    2003-01-01

    In this study, we evaluate numerical simulations of the twentieth century climate, focusing on the changes in the intensity of the global water cycle. A new diagnostic of atmospheric water vapor cycling rate is developed and employed, that relies on constituent tracers predicted at the model time step. This diagnostic is compared to a simplified traditional calculation of cycling rate, based on monthly averages of precipitation and total water content. The mean sensitivity of both diagnostics to variations in climate forcing is comparable. However, the new diagnostic produces systematically larger values and more variability than the traditional average approach. Climate simulations were performed using SSTs of the early (1902-1921) and late (1979- 1998) twentieth century along with the appropriate C02 forcing. In general, the increase of global precipitation with the increases in SST that occurred between the early and late twentieth century is small. However, an increase of atmospheric temperature leads to a systematic increase in total precipitable water. As a result, the residence time of water in the atmosphere increased, indicating a reduction of the global cycling rate. This result was explored further using a number of 50-year climate simulations from different models forced with observed SST. The anomalies and trends in the cycling rate and hydrologic variables of different GCMs are remarkably similar. The global annual anomalies of precipitation show a significant upward trend related to the upward trend of surface temperature, during the latter half of the twentieth century. While this implies an increase in the hydrologic cycle intensity, a concomitant increase of total precipitable water again leads to a decrease in the calculated global cycling rate. An analysis of the land/sea differences shows that the simulated precipitation over land has a decreasing trend while the oceanic precipitation has an upward trend consistent with previous studies and the

  1. Global modelling of Cryptosporidium in surface water

    Science.gov (United States)

    Vermeulen, Lucie; Hofstra, Nynke

    2016-04-01

    Introduction Waterborne pathogens that cause diarrhoea, such as Cryptosporidium, pose a health risk all over the world. In many regions quantitative information on pathogens in surface water is unavailable. Our main objective is to model Cryptosporidium concentrations in surface waters worldwide. We present the GloWPa-Crypto model and use the model in a scenario analysis. A first exploration of global Cryptosporidium emissions to surface waters has been published by Hofstra et al. (2013). Further work has focused on modelling emissions of Cryptosporidium and Rotavirus to surface waters from human sources (Vermeulen et al 2015, Kiulia et al 2015). A global waterborne pathogen model can provide valuable insights by (1) providing quantitative information on pathogen levels in data-sparse regions, (2) identifying pathogen hotspots, (3) enabling future projections under global change scenarios and (4) supporting decision making. Material and Methods GloWPa-Crypto runs on a monthly time step and represents conditions for approximately the year 2010. The spatial resolution is a 0.5 x 0.5 degree latitude x longitude grid for the world. We use livestock maps (http://livestock.geo-wiki.org/) combined with literature estimates to calculate spatially explicit livestock Cryptosporidium emissions. For human Cryptosporidium emissions, we use UN population estimates, the WHO/UNICEF JMP sanitation country data and literature estimates of wastewater treatment. We combine our emissions model with a river routing model and data from the VIC hydrological model (http://vic.readthedocs.org/en/master/) to calculate concentrations in surface water. Cryptosporidium survival during transport depends on UV radiation and water temperature. We explore pathogen emissions and concentrations in 2050 with the new Shared Socio-economic Pathways (SSPs) 1 and 3. These scenarios describe plausible future trends in demographics, economic development and the degree of global integration. Results and

  2. Aqueduct: an interactive tool to empower global water risk assessment

    Science.gov (United States)

    Reig, Paul; Gassert, Francis

    2013-04-01

    The Aqueduct Water Risk Atlas (Aqueduct) is a publicly available, global database and interactive tool that maps indicators of water related risks for decision makers worldwide. Aqueduct makes use of the latest geo-statistical modeling techniques to compute a composite index and translate the most recently available hydrological data into practical information on water related risks for companies, investors, and governments alike. Twelve global indicators are grouped into a Water Risk Framework designed in response to the growing concerns from private sector actors around water scarcity, water quality, climate change, and increasing demand for freshwater. The Aqueduct framework includes indicators of water stress, variability in supply, storage, flood, drought, groundwater, water quality and social conflict, addressing both spatial and temporal variation in water hazards. It organizes indicators into three categories of risk that bring together multiple dimensions of water related risk into comprehensive aggregated scores, which allow for dynamic weighting to capture users' unique exposure to water hazards. All information is compiled into an online, open access platform, from which decision-makers can view indicators, scores, and maps, conduct global risk assessments, and export data and shape files for further analysis. Companies can use this tool to evaluate their exposure to water risks across operations and supply chains, investors to assess water-related risks in their portfolio, and public-sector actors to better understand water security. Additionally, the open nature of the data and maps allow other organizations to build off of this effort with new research, for example in the areas of water-energy or water-food relationships. This presentation will showcase the Aqueduct Water Risk Atlas online tool and the features and functionalities it offers, as well as explain how it can be used for both private and public sector applications. The session will

  3. Water stress detection using radar

    NARCIS (Netherlands)

    van Emmerik, T.H.M.

    2017-01-01

    Vegetation is a crucial part of the water and carbon cycle. Through photosynthesis carbon is assimilated for biomass production, and oxygen is released into the atmosphere. During this process, water is transpired through the stomata, and is redistributed in the plant. Transpired water is refilled

  4. Water Replacement Schedules in Heat Stress

    Science.gov (United States)

    Londeree, Ben R.; and others

    1969-01-01

    Although early ingestion of cold water appears to lead to greater relief from heat stress during physical exertion than late ingestion, this difference is reduced toward the end of an hour's work in high heat and humidity. (CK)

  5. Modern Estimates of Global Water Cycle Fluxes

    Science.gov (United States)

    Rodell, M.; Beaudoing, H. K.; L'Ecuyer, T. S.; Olson, W. S.

    2014-12-01

    The goal of the first phase of the NASA Energy and Water Cycle Study (NEWS) Water and Energy Cycle Climatology project was to develop "state of the global water cycle" and "state of the global energy cycle" assessments based on data from modern ground and space based observing systems and data integrating models. Here we describe results of the water cycle assessment, including mean annual and monthly fluxes over continents and ocean basins during the first decade of the millennium. To the extent possible, the water flux estimates are based on (1) satellite measurements and (2) data-integrating models. A careful accounting of uncertainty in each flux was applied within a routine that enforced multiple water and energy budget constraints simultaneously in a variational framework, in order to produce objectively-determined, optimized estimates. Simultaneous closure of the water and energy budgets caused the ocean evaporation and precipitation terms to increase by about 10% and 5% relative to the original estimates, mainly because the energy budget required turbulent heat fluxes to be substantially larger in order to balance net radiation. In the majority of cases, the observed annual, surface and atmospheric water budgets over the continents and oceans close with much less than 10% residual. Observed residuals and optimized uncertainty estimates are considerably larger for monthly surface and atmospheric water budget closure, often nearing or exceeding 20% in North America, Eurasia, Australia and neighboring islands, and the Arctic and South Atlantic Oceans. The residuals in South America and Africa tend to be smaller, possibly because cold land processes are a non-issue. Fluxes are poorly observed over the Arctic Ocean, certain seas, Antarctica, and the Australasian and Indonesian Islands, leading to reliance on atmospheric analysis estimates. Other details of the study and future directions will be discussed.

  6. Root water extraction under combined water and osmotic stress

    NARCIS (Netherlands)

    Jong van Lier, de Q.; Dam, van J.C.; Metselaar, K.

    2009-01-01

    Using a numerical implicit model for root water extraction by a single root in a symmetric radial flow problem, based on the Richards equation and the combined convection-dispersion equation, we investigated some aspects of the response of root water uptake to combined water and osmotic stress. The

  7. Integrated Water Resources Management: A Global Review

    Science.gov (United States)

    Srinivasan, V.; Cohen, M.; Akudago, J.; Keith, D.; Palaniappan, M.

    2011-12-01

    The diversity of water resources endowments and the societal arrangements to use, manage, and govern water makes defining a single paradigm or lens through which to define, prioritize and evaluate interventions in the water sector particularly challenging. Integrated Water Resources Management (IWRM) emerged as the dominant intervention paradigm for water sector interventions in the early 1990s. Since then, while many successful implementations of IWRM have been demonstrated at the local, basin, national and trans-national scales, IWRM has also been severely criticized by the global water community as "having a dubious record that has never been comprehensively analyzed", "curiously ambiguous", and "ineffective at best and counterproductive at worst". Does IWRM hold together as a coherent paradigm or is it a convenient buzzword to describe a diverse collection of water sector interventions? We analyzed 184 case study summaries of IWRM interventions on the Global Water Partnership (GWP) website. The case studies were assessed to find the nature, scale, objectives and outcomes of IWRM. The analysis does not suggest any coherence in IWRM as a paradigm - but does indicate distinct regional trends in IWRM. First, IWRM was done at very different scales in different regions. In Africa two-thirds of the IWRM interventions involved creating national or transnational organizations. In contrast, in Asia and South America, almost two-thirds were watershed, basin, or local body initiatives. Second, IWRM interventions involved very different types of activities in different regions. In Africa and Europe, IWRM entailed creation of policy documents, basin plans and institution building. In contrast, in Asia and Latin America the interventions were much more likely to entail new technology, infrastructure or watershed measures. In Australia, economic measures, new laws and enforcement mechanisms were more commonly used than anywhere else.

  8. An updated view of global water cycling

    Science.gov (United States)

    Houser, P. R.; Schlosser, A.; Lehr, J.

    2009-04-01

    Unprecedented new observation capacities combined with revolutions in modeling, we are poised to make huge advances in water cycle assessment, understanding, and prediction. To realize this goal, we must develop a discipline of prediction and verification through the integration of water and energy cycle observations and models, and to verify model predictions against observed phenomena to ensure that research delivers reliable improvements in prediction skill. Accomplishing these goals will require, in part, an accurate accounting of the key reservoirs and fluxes associated with the global water and energy cycle, including their spatial and temporal variability, through integration of all necessary observations and research tools. A brief history of the lineage of the conventional water balance and a summary accounting of all major parameters of the water balance using highly respected secondary sources will be presented. Principally, recently published peer reviewed papers reporting results of original work involving direct measurements and new data generated by high-tech devices (e.g. satellite / airborne instruments, supercomputers, geophysical tools) will be employed. This work lends credence to the conventional water balance ideas, but also reveals anachronistic scientific concepts/models, questionable underlying data, longstanding oversights and outright errors in the water balance.

  9. Growth and physiological responses to water and nutrient stress in ...

    African Journals Online (AJOL)

    Growth and physiological responses to water and nutrient stress in oil palm. ... changes in growth, physiology and nutrient concentration in response to two watering regimes (well-watered and water-stress conditions) and ... from 32 Countries:.

  10. Hybrid Analysis of Blue Water Consumption and Water Scarcity Implications at the Global, National, and Basin Levels in an Increasingly Globalized World.

    Science.gov (United States)

    Wang, Ranran; Zimmerman, Julie

    2016-05-17

    As the fifth global water footprint assessment, this study enhanced previous estimates of national blue water consumption (including fresh surface and groundwater) and main economic activities with (1) improved spatial and sectoral resolution and (2) quantified the impacts of virtual water trade on water use and water stress at both the national and basin level. In 2007, 1194 Gm(3) of blue water was consumed globally for human purposes. The consuming (producing) of primary and manufactured goods and services from the sectors of "Primary Crops and Livestock", "Primary Energy and Minerals", "Processed Food and Beverages", "Non-food Manufactured Products", "Electricity", "Commercial and Public Services", and "Households" accounted for 33% (91%), ∼ 0% (1%), 37% (water consumption, respectively. The considerable differences in sectoral water consumption accounted for by the two perspectives (consumption- vs production-based) highlight the significance of the water consumed indirectly, upstream in the supply chain (i.e., > 70% of total blue water consumption) while offering additional insights into the water implications of critical interconnected economic activities, such as the water-energy nexus. With 145 Gm(3) (12%) of the blue water consumption embedded in the goods and services traded internationally, 89 countries analyzed were net blue water importers at the national level. On the basin level, the impacts of virtual water trade on water stress were statistically significant for basins across the world and within 104 countries; virtual water trade mitigated water stress for the basins within 85 of the 104 countries, including all of those where there are moderate and greater water stress countrywide (except Italy).

  11. Assessing corn water stress using spectral reflectance

    Science.gov (United States)

    Mefford, Brenna S.

    Multiple remote sensing techniques have been developed to identify crop water stress, but some methods may be difficult for farmers to apply. Unlike most techniques, shortwave vegetation indices can be calculated using satellite, aerial, or ground imagery from the green (525-600 nm), red (625-700 nm), and near infrared (750-900 nm) spectral bands. If vegetation indices can be used to monitor crop water stress, growers could use this information as a quick low-cost guideline for irrigation management, thus helping save water by preventing over irrigating. This study occurred in the 2013 growing season near Greeley, CO, where pressurized drip irrigation was used to irrigate twelve corn ( Zea mays L.) treatments of varying water deficit. Multispectral data was collected and four different vegetation indices were evaluated: Normalized Difference Vegetation Index (NDVI), Optimized Soil-Adjusted Vegetation Index (OSAVI), Green Normalized Difference Vegetation Index (GNDVI), and the Wide Dynamic Range Vegetation Index (WDRVI). The four vegetation indices were compared to corn water stress as indicated by the stress coefficient (Ks) and water deficit in the root zone, calculated by using a water balance that monitors crop evapotranspiration (ET), irrigation events, precipitation events, and deep percolation. ET for the water balance was calculated using two different methods for comparison purposes: (1) calculation of the stress coefficient (Ks) using FAO-56 standard procedures; (2) use of canopy temperature ratio (Tc ratio) of a stressed crop to a non-stressed crop to calculate Ks. It was found that obtaining Ks from Tc ratio is a viable option, and requires less data to obtain than Ks from FAO-56. In order to compare the indices to Ks, vegetation ratios were developed in the process of normalization. Vegetation ratios are defined as the non-stressed vegetation index divided by the stressed vegetation index. Results showed that vegetation ratios were sensitive to water

  12. Perspectives : How global food traders manage our water

    NARCIS (Netherlands)

    Warner, J.F.; Keulertz, M.; Sojamo, S.

    2015-01-01

    To many analysts, global water governance is about getting the institutions right: more accountable water users and more public participation in decisions. But are we barking up the right tree? In this analysis, we argue that when analysing global water governance, one needs to look at the global

  13. Open Source Tools for Assessment of Global Water Availability, Demands, and Scarcity

    Science.gov (United States)

    Li, X.; Vernon, C. R.; Hejazi, M. I.; Link, R. P.; Liu, Y.; Feng, L.; Huang, Z.; Liu, L.

    2017-12-01

    Water availability and water demands are essential factors for estimating water scarcity conditions. To reproduce historical observations and to quantify future changes in water availability and water demand, two open source tools have been developed by the JGCRI (Joint Global Change Research Institute): Xanthos and GCAM-STWD. Xanthos is a gridded global hydrologic model, designed to quantify and analyze water availability in 235 river basins. Xanthos uses a runoff generation and a river routing modules to simulate both historical and future estimates of total runoff and streamflows on a monthly time step at a spatial resolution of 0.5 degrees. GCAM-STWD is a spatiotemporal water disaggregation model used with the Global Change Assessment Model (GCAM) to spatially downscale global water demands for six major enduse sectors (irrigation, domestic, electricity generation, mining, and manufacturing) from the region scale to the scale of 0.5 degrees. GCAM-STWD then temporally downscales the gridded annual global water demands to monthly results. These two tools, written in Python, can be integrated to assess global, regional or basin-scale water scarcity or water stress. Both of the tools are extensible to ensure flexibility and promote contribution from researchers that utilize GCAM and study global water use and supply.

  14. Modelling of the Global Geopotential Energy & Stress Field

    DEFF Research Database (Denmark)

    Schiffer, Christian; Nielsen, S.B.

    Lateral density and topography variations yield in and important contribution to the lithospheric stress field. The leading quantity is the Geopotential Energy, the integrated lithostatic pressure in a rock column. The horizontal gradient of this quantity is related to horizontal stresses through...... the Equations of equilibrium of stresses. The Geopotential Energy furthermore can be linearly related to the Geoid under assumption of local isostasy. Satellite Geoid measurements contain, however, also non-isostatic deeper mantle responses of long wavelength. Unfortunately, high-pass filtering of the Geoid...... flow in the presence of local isostasy and a steady state geotherm. Subsequently we use a FEM code to solve the Equations of equilibrium of stresses for a three dimensional elastic shell. The modelled results are shown and compared with the global stress field and other publications....

  15. Use of crop water stress index for monitoring water stress in some sinanthropic plant species

    Directory of Open Access Journals (Sweden)

    Marinela Roxana ROŞESCU

    2010-11-01

    Full Text Available The water stress indicator (crop water stress index, CWSI is a measure of the transpiration rate of a plant, influenced by the leaf and air temperature difference from the plant’s vicinity and the air pressure deficit of the water vapors from the atmosphere. The experiments were realized in July-August 2008 and 2009 for six species in the cities Pitesti, Mioveni and Maracineni: Cichorium intybus L., Conyza canadensis (L. Cronq., Erigeron annuus L. (Pers., Lactuca serriola Torn., Polygonum aviculare L. and Echinochloa crus-galli (L. Beauv. For those species we calculated the CWSI to estimate the water stress on the selected plants in the urban environment conditions. The analyzed species were exposed to a less accentuated water stress while vegetating in the soil and to a more intense one they were grown in the asphalt cracks. Cichorium intybus had the smallest CWSI value (0.26 while Lactuca serriola the highest one (0.44.

  16. Contrasting extremes in water-related stresses determine species survival

    Science.gov (United States)

    Bartholomeus, R. P.; Witte, J. P. M.; van Bodegom, P. M.; van Dam, J. C.; Aerts, R.

    2012-04-01

    In temperate climates, soil moisture, in concert with nutrient availability and soil acidity, is the most important environmental filter in determining local plant species composition, as it determines the availability of both oxygen and water to plant roots. These resources are indispensable for meeting the physiological demands of plants. Especially the occurrence of both excessive dry and wet moisture conditions at a particular site has strong implications for the survival of species, because plants need traits that allow them to respond to such counteracting conditions. However, adapting to one stress may go at the cost of the other, i.e. there exists a trade-off in the tolerance for wet conditions and the tolerance for dry conditions. Until now, both large-scale (global) and plot-scale effects of soil moisture conditions on plant species composition have mostly been investigated through indirect environmental measures, which do not include the key soil physical and plant physiological processes in the soil-plant-atmosphere system. Moreover, researchers only determined effects of one of the water-related stresses, i.e. either oxygen or drought stress. In order to quantify both oxygen and drought stress with causal measures, we focused on interacting meteorological, soil physical, microbial, and plant physiological processes in the soil-plant-atmosphere system. We simulated these plant stresses with a novel, process-based approach, incorporating in detail the interacting processes in the soil-plant-atmosphere interface. High variability and extremes in resource availability can be highly detrimental to plant species ('you can only die once'). We show that co-occurrence of oxygen and drought stress reduces the percentage of specialists within a vegetation plot. The percentage of non-specialists within a vegetation plot, however, decreases significantly with increasing stress as long as only one of the stresses prevails, but increases significantly with an

  17. Light energy dissipation under water stress conditions

    International Nuclear Information System (INIS)

    Stuhlfauth, T.; Scheuermann, R.; Fock, H.P.

    1990-01-01

    Using 14 CO 2 gas exchange and metabolite analyses, stomatal as well as total internal CO 2 uptake and evolution were estimated. Pulse modulated fluorescence was measured during induction and steady state of photosynthesis. Leaf water potential of Digitalis lanata EHRH. plants decreased to -2.5 megapascals after withholding irrigation. By osmotic adjustment, leaves remained turgid and fully exposed to irradiance even at severe water stress. Due to the stress-induced reduction of stomatal conductance, the stomatal CO 2 exchange was drastically reduced, whereas the total CO 2 uptake and evolution were less affected. Stomatal closure induced an increase in the reassimilation of internally evolved CO 2 . This CO 2 -recycling consumes a significant amount of light energy in the form of ATP and reducing equivalents. As a consequence, the metabolic demand for light energy is only reduced by about 40%, whereas net photosynthesis is diminished by about 70% under severe stress conditions. By CO 2 recycling, carbon flux, enzymatic substrate turnover and consumption of light energy were maintained at high levels, which enabled the plant to recover rapidly after rewatering. In stressed D. lanata plants a variable fluorescence quenching mechanism, termed coefficient of actinic light quenching, was observed. Besides water conservation, light energy dissipation is essential and involves regulated metabolic variations

  18. Light energy dissipation under water stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Stuhlfauth, T.; Scheuermann, R.; Fock, H.P. (Universitaet Kaiserslautern (West Germany))

    1990-04-01

    Using {sup 14}CO{sub 2} gas exchange and metabolite analyses, stomatal as well as total internal CO{sub 2} uptake and evolution were estimated. Pulse modulated fluorescence was measured during induction and steady state of photosynthesis. Leaf water potential of Digitalis lanata EHRH. plants decreased to {minus}2.5 megapascals after withholding irrigation. By osmotic adjustment, leaves remained turgid and fully exposed to irradiance even at severe water stress. Due to the stress-induced reduction of stomatal conductance, the stomatal CO{sub 2} exchange was drastically reduced, whereas the total CO{sub 2} uptake and evolution were less affected. Stomatal closure induced an increase in the reassimilation of internally evolved CO{sub 2}. This CO{sub 2}-recycling consumes a significant amount of light energy in the form of ATP and reducing equivalents. As a consequence, the metabolic demand for light energy is only reduced by about 40%, whereas net photosynthesis is diminished by about 70% under severe stress conditions. By CO{sub 2} recycling, carbon flux, enzymatic substrate turnover and consumption of light energy were maintained at high levels, which enabled the plant to recover rapidly after rewatering. In stressed D. lanata plants a variable fluorescence quenching mechanism, termed coefficient of actinic light quenching, was observed. Besides water conservation, light energy dissipation is essential and involves regulated metabolic variations.

  19. Serendipity: Global Detection and Quantification of Plant Stress

    Science.gov (United States)

    Schimel, D.; Verma, M.; Drewry, D.

    2016-12-01

    Detecting and quantifying plant stress is a grand challenge for remote sensing, and is important for understanding climate impacts on ecosystems broadly and also for early warning systems supporting food security. The long record from moderate resolution sensors providing frequent data has allowed using phenology to detect stress in forest and agroecosystems, but can fail or give ambiguous results when stress occurs during later phases of growth and in high leaf area systems. The recent recognition that greenhouse gas satellites such as GOSAT and OCO-2 observe Solar-Induced Fluorescence has added a new and complementary tool for the quantification of stress but algorithms to detect and quantify stress using SIF are in their infancy. Here we report new results showing a more complex response of SIF to stress by evaluating spaceborne SIF against in situ eddy covariance data. The response observed is as predicted by theory, and shows that SIF, used in conjunction with moderate resolution remote sensing, can detect and likely quantify stress by indexing the nonlinear part of the SIF-GPP relationship using the photochemical reflectance index and remotely observed light absorption. There are several exciting opportunities on the near horizon for the implementation of SIF, together with syngeristic measurements such as PRI and evapotranspiration that suggest the next few years will be a golden age for global ecology. Adancing the science and associated algorithms now is essential to fully exploiting the next wave of missions.

  20. Human and climate impacts on global water resources

    NARCIS (Netherlands)

    Wada, Y.|info:eu-repo/dai/nl/341387819

    2013-01-01

    Over past decades, terrestrial water fluxes have been affected by humans at an unprecedented scale and the fingerprints that humans have left on Earth’s water resources are turning up in a diverse range of records. In this thesis, a state-of-the-art global hydrological model (GHM) and global water

  1. Water stress detection in the Amazon using radar

    Science.gov (United States)

    van Emmerik, Tim; Steele-Dunne, Susan; Paget, Aaron; Oliveira, Rafael S.; Bittencourt, Paulo R. L.; Barros, Fernanda de V.; van de Giesen, Nick

    2017-07-01

    The Amazon rainforest plays an important role in the global water and carbon cycle, and though it is predicted to continue drying in the future, the effect of drought remains uncertain. Developments in remote sensing missions now facilitate large-scale observations. The RapidScat scatterometer (Ku band) mounted on the International Space Station observes the Earth in a non-Sun-synchronous orbit, which allows for studying changes in the diurnal cycle of radar backscatter over the Amazon. Diurnal cycles in backscatter are significantly affected by the state of the canopy, especially during periods of increased water stress. We use RapidScat backscatter time series and water deficit measurements from dendrometers in 20 trees during a 9 month period to relate variations in backscatter to increased tree water deficit. Morning radar bacskcatter dropped significantly with increased tree water deficit measured with dendrometers. This provides unique observational evidence that demonstrates the sensitivity of radar backscatter to vegetation water stress, highlighting the potential of drought detection and monitoring using radar.

  2. Water dependency and water exploitation at global scale as indicators of water security

    Science.gov (United States)

    De Roo, A. P. J.; Beck, H.; Burek, P.; Bernard, B.

    2015-12-01

    A water dependency index has been developed indicating the dependency of water consumption from upstream sources of water, sometimes across (multiple) national border. This index is calculated at global scale using the 0.1 global LISFLOOD hydrological modelling system forced by WFDEI meteorological data for the timeframe 1979-2012. The global LISFLOOD model simulates the most important hydrological processes, as well as water abstraction and consumption from various sectors, and flood routing, at daily scale, with sub-timesteps for routing and subgrid parameterization related to elevation and landuse. The model contains also options for water allocation, to allow preferences of water use for particular sectors in water scarce periods. LISFLOOD is also used for the Global Flood Awareness System (GloFAS), the European Flood Awareness System (EFAS), continental scale climate change impact studies on floods and droughts. The water dependency indicator is calculated on a monthly basis, and various annual and multiannual indicators are derived from it. In this study, the indicator will be compared against water security areas known from other studies. Other indicators calculated are the Water Exploitation Index (WEI+), which is a commonly use water security indicator in Europe, and freshwater resources per capita indicators at regional, national and river basin scale. Several climate scnearios are run to indicate future trends in water security.

  3. Seasonal water storage, stress modulation and California seismicity

    Science.gov (United States)

    Johnson, C. W.; Burgmann, R.; Fu, Y.

    2017-12-01

    Establishing what controls the timing of earthquakes is fundamental to understanding the nature of the earthquake cycle and critical to determining time-dependent earthquake hazard. Seasonal loading provides a natural laboratory to explore the crustal response to a quantifiable transient force. In California, the accumulation of winter snowpack in the Sierra Nevada, surface water in lakes and reservoirs, and groundwater in sedimentary basins follow the annual cycle of wet winters and dry summers. The surface loads resulting from the seasonal changes in water storage produce elastic deformation of the Earth's crust. We used 9 years of global positioning system (GPS) vertical deformation time series to constrain models of monthly hydrospheric loading and the resulting stress changes on fault planes of small earthquakes. Previous studies posit that temperature, atmospheric pressure, or hydrologic changes may strain the lithosphere and promote additional earthquakes above background levels. Depending on fault geometry, the addition or removal of water increases the Coulomb failure stress. The largest stress amplitudes are occurring on dipping reverse faults in the Coast Ranges and along the eastern Sierra Nevada range front. We analyze 9 years of M≥2.0 earthquakes with known focal mechanisms in northern and central California to resolve fault-normal and fault-shear stresses for the focal geometry. Our results reveal 10% more earthquakes occurring during slip-encouraging fault-shear stress conditions and suggest that earthquake populations are modulated at periods of natural loading cycles, which promote failure by stress changes on the order of 1-5 kPa. We infer that California seismicity rates are modestly modulated by natural hydrological loading cycles.

  4. The global distribution of giant radiating dike swarms on Venus: Implications for the global stress state

    Science.gov (United States)

    Grosfils, Eric B.; Head, James W.

    1994-01-01

    Magellan radar data of Venus reveal 163 large radial lineament systems composed of graben, fissure, and fracture elements. On the basis of their structure, plan view geometry, and volcanic associations, at least 72% are interpreted to have formed primarily through subsurface dike swarm emplacement, the remainder through uplift or a combination of these two mechanisms. The population of swarms is used to determine regional and global stress orientation. The stress configuration recorded from 330-210 deg E (Aphrodite Terra) is best explained by isostatic compensation of existing long wavelength topography or coupling between mantle flow and the lithosphere. The rest are correlated with concentrations of rifting and volcanism in the Beta-Atla-Themis region. The global stress field on Venus is different than that of Earth, where plate boundary forces dominate.

  5. An integrated model for the assessment of global water resources – Part 2: Applications and assessments

    Directory of Open Access Journals (Sweden)

    N. Hanasaki

    2008-07-01

    Full Text Available To assess global water resources from the perspective of subannual variation in water availability and water use, an integrated water resources model was developed. In a companion report, we presented the global meteorological forcing input used to drive the model and six modules, namely, the land surface hydrology module, the river routing module, the crop growth module, the reservoir operation module, the environmental flow requirement module, and the anthropogenic withdrawal module. Here, we present the results of the model application and global water resources assessments. First, the timing and volume of simulated agriculture water use were examined because agricultural use composes approximately 85% of total consumptive water withdrawal in the world. The estimated crop calendar showed good agreement with earlier reports for wheat, maize, and rice in major countries of production. In major countries, the error in the planting date was ±1 mo, but there were some exceptional cases. The estimated irrigation water withdrawal also showed fair agreement with country statistics, but tended to be underestimated in countries in the Asian monsoon region. The results indicate the validity of the model and the input meteorological forcing because site-specific parameter tuning was not used in the series of simulations. Finally, global water resources were assessed on a subannual basis using a newly devised index. This index located water-stressed regions that were undetected in earlier studies. These regions, which are indicated by a gap in the subannual distribution of water availability and water use, include the Sahel, the Asian monsoon region, and southern Africa. The simulation results show that the reservoir operations of major reservoirs (>1 km3 and the allocation of environmental flow requirements can alter the population under high water stress by approximately −11% to +5% globally. The integrated model is applicable to

  6. Water stress induced changes in antioxidant enzymes, membrane ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-01

    Dec 1, 2009 ... membrane stability index occurred under water stress. Accession 320 ... yielding wheat varieties for areas affected by water stress. (Mujtaba ...... Peroxidase activity in golden delicious apples as a ... Food Chem. 24: 200-201.

  7. Evolution of the global virtual water trade network.

    Science.gov (United States)

    Dalin, Carole; Konar, Megan; Hanasaki, Naota; Rinaldo, Andrea; Rodriguez-Iturbe, Ignacio

    2012-04-17

    Global freshwater resources are under increasing pressure from economic development, population growth, and climate change. The international trade of water-intensive products (e.g., agricultural commodities) or virtual water trade has been suggested as a way to save water globally. We focus on the virtual water trade network associated with international food trade built with annual trade data and annual modeled virtual water content. The evolution of this network from 1986 to 2007 is analyzed and linked to trade policies, socioeconomic circumstances, and agricultural efficiency. We find that the number of trade connections and the volume of water associated with global food trade more than doubled in 22 years. Despite this growth, constant organizational features were observed in the network. However, both regional and national virtual water trade patterns significantly changed. Indeed, Asia increased its virtual water imports by more than 170%, switching from North America to South America as its main partner, whereas North America oriented to a growing intraregional trade. A dramatic rise in China's virtual water imports is associated with its increased soy imports after a domestic policy shift in 2000. Significantly, this shift has led the global soy market to save water on a global scale, but it also relies on expanding soy production in Brazil, which contributes to deforestation in the Amazon. We find that the international food trade has led to enhanced savings in global water resources over time, indicating its growing efficiency in terms of global water use.

  8. Global Anthropogenic Phosphorus Loads to Fresh Water, Grey Water Footprint and Water Pollution Levels: A High-Resolution Global Study

    Science.gov (United States)

    Mekonnen, M. M.; Hoekstra, A. Y. Y.

    2014-12-01

    We estimated anthropogenic phosphorus (P) loads to freshwater, globally at a spatial resolution level of 5 by 5 arc minute. The global anthropogenic P load to freshwater systems from both diffuse and point sources in the period 2002-2010 was 1.5 million tonnes per year. China contributed about 30% to this global anthropogenic P load. India was the second largest contributor (8%), followed by the USA (7%), Spain and Brazil each contributing 6% to the total. The domestic sector contributed the largest share (54%) to this total followed by agriculture (38%) and industry (8%). Among the crops, production of cereals had the largest contribution to the P loads (32%), followed by fruits, vegetables, and oil crops, each contributing about 15% to the total. We also calculated the resultant grey water footprints, and relate the grey water footprints per river basin to runoff to calculate the P-related water pollution level (WPL) per catchment.

  9. Implications of various land use change scenarios on global water scarcity over the 21st century

    Science.gov (United States)

    Liu, Y.; Hejazi, M. I.; Vernon, C. R.; Li, X.; Le Page, Y.; Calvin, K. V.

    2017-12-01

    While the effects of land use and land cover change (LULCC) on hydrological processes (e.g., runoff, peak flow and discharge) and water availability have been extensively researched, the impacts of LULCC on water scarcity has been rarely investigated. Water scarcity, usually defined as the ratio of water demand to available renewable water supply. The involved water demand is an important human-dimension factor, which is affected by both socio-economic conditions (e.g., population, income) as well as LULCC (e.g., the amount of land we dedicate for food, feed, and fuel crops). Recent studies have assessed the combined effects of climate change and human interventions (e.g., dams, water withdrawals and LULCC) on water scarcity, but none to date has focused on the implications of different pathways of LULCC alone on water scarcity. We establish a set of LULCC scenarios under changing climate and socioeconomic pathways using an integrated assessment model - Global Change Assessment Model (GCAM), which integrates natural systems (e.g., water supply, ecosystems, climate) and human systems (e.g., water demand, land use, economy, food, energy, population). The LULCC scenarios encompass varying degrees of protected areas, different magnitudes of crop/bioenergy production and subsidies, and whether to penalize potential land use emissions from bioenergy production (e.g., loss of wood carbon stock from land conversion). Then we investigate how water scarcity responds to LULCC and how the distribution of global population under severe water stress varies in the 21st century. Preliminary results indicate that the LULCC-induced changes in water scarcity are overall small at the global scale (water stress and population being affected. Findings from this research could be used to inform strategies focused on alleviating water stress around the world.

  10. Global hydrobelts: improved reporting scale for water-related issues?

    Science.gov (United States)

    Meybeck, M.; Kummu, M.; Dürr, H. H.

    2012-08-01

    Questions related to water such as its availability, water needs or stress, or management, are mapped at various resolutions at the global scale. They are reported at many scales, mostly along political or continental boundaries. As such, they ignore the fundamental heterogeneity of the hydroclimate and the natural boundaries of the river basins. Here, we describe the continental landmasses according to eight global-scale hydrobelts strictly limited by river basins, defined at a 30' (0.5°) resolution. The belts were defined and delineated, based primarily on the annual average temperature (T) and runoff (q), to maximise interbelt differences and minimise intrabelt variability. The belts were further divided into 29 hydroregions based on continental limits. This new global puzzle defines homogeneous and near-contiguous entities with similar hydrological and thermal regimes, glacial and postglacial basin histories, endorheism distribution and sensitivity to climate variations. The Mid-Latitude, Dry and Subtropical belts have northern and southern analogues and a general symmetry can be observed for T and q between them. The Boreal and Equatorial belts are unique. The hydroregions (median size 4.7 Mkm2) contrast strongly, with the average q ranging between 6 and 1393 mm yr-1 and the average T between -9.7 and +26.3 °C. Unlike the hydroclimate, the population density between the North and South belts and between the continents varies greatly, resulting in pronounced differences between the belts with analogues in both hemispheres. The population density ranges from 0.7 to 0.8 p km-2 for the North American Boreal and some Australian hydroregions to 280 p km-2 for the Asian part of the Northern Mid-Latitude belt. The combination of population densities and hydroclimate features results in very specific expressions of water-related characteristics in each of the 29 hydroregions. Our initial tests suggest that hydrobelt and hydroregion divisions are often more

  11. Global change and water resources in the next 100 years

    Science.gov (United States)

    Larsen, Matthew C.; Hirsch, R.M.

    2010-01-01

    We are in the midst of a continental-scale, multi-year experiment in the United States, in which we have not defined our testable hypotheses or set the duration and scope of the experiment, which poses major water-resources challenges for the 21st century. What are we doing? We are expanding population at three times the national growth rate in our most water-scarce region, the southwestern United States, where water stress is already great and modeling predicts decreased streamflow by the middle of this century. We are expanding irrigated agriculture from the west into the east, particularly to the southeastern states, where increased competition for ground and surface water has urban, agricultural, and environmental interests at odds, and increasingly, in court. We are expanding our consumption of pharmaceutical and personal care products to historic high levels and disposing them in surface and groundwater, through sewage treatment plants and individual septic systems. These substances are now detectable at very low concentrations and we have documented significant effects on aquatic species, particularly on fish reproduction function. We don’t yet know what effects on human health may emerge, nor do we know if we need to make large investments in water treatment systems, which were not designed to remove these substances. These are a few examples of our national-scale experiment. In addition to these water resources challenges, over which we have some control, climate change models indicate that precipitation and streamflow patterns will change in coming decades, with western mid-latitude North America generally drier. We have already documented trends in more rain and less snow in western mountains. This has large implications for water supply and storage, and groundwater recharge. We have documented earlier snowmelt peak spring runoff in northeastern and northwestern States, and western montane regions. Peak runoff is now about two weeks earlier than it was

  12. A global sensitivity analysis of crop virtual water content

    Science.gov (United States)

    Tamea, S.; Tuninetti, M.; D'Odorico, P.; Laio, F.; Ridolfi, L.

    2015-12-01

    The concepts of virtual water and water footprint are becoming widely used in the scientific literature and they are proving their usefulness in a number of multidisciplinary contexts. With such growing interest a measure of data reliability (and uncertainty) is becoming pressing but, as of today, assessments of data sensitivity to model parameters, performed at the global scale, are not known. This contribution aims at filling this gap. Starting point of this study is the evaluation of the green and blue virtual water content (VWC) of four staple crops (i.e. wheat, rice, maize, and soybean) at a global high resolution scale. In each grid cell, the crop VWC is given by the ratio between the total crop evapotranspiration over the growing season and the crop actual yield, where evapotranspiration is determined with a detailed daily soil water balance and actual yield is estimated using country-based data, adjusted to account for spatial variability. The model provides estimates of the VWC at a 5x5 arc minutes and it improves on previous works by using the newest available data and including multi-cropping practices in the evaluation. The model is then used as the basis for a sensitivity analysis, in order to evaluate the role of model parameters in affecting the VWC and to understand how uncertainties in input data propagate and impact the VWC accounting. In each cell, small changes are exerted to one parameter at a time, and a sensitivity index is determined as the ratio between the relative change of VWC and the relative change of the input parameter with respect to its reference value. At the global scale, VWC is found to be most sensitive to the planting date, with a positive (direct) or negative (inverse) sensitivity index depending on the typical season of crop planting date. VWC is also markedly dependent on the length of the growing period, with an increase in length always producing an increase of VWC, but with higher spatial variability for rice than for

  13. Modelling global fresh surface water temperature

    NARCIS (Netherlands)

    Beek, L.P.H. van; Eikelboom, T.; Vliet, M.T.H. van; Bierkens, M.F.P.

    2011-01-01

    Temperature directly determines a range of water physical properties including vapour pressure, surface tension, density and viscosity, and the solubility of oxygen and other gases. Indirectly water temperature acts as a strong control on fresh water biogeochemistry, influencing sediment

  14. Plants in water-controlled ecosystems: active role in hydrologic processes and response to water stress. III. Vegetation water stress

    Science.gov (United States)

    Porporato, A.; Laio, F.; Ridolfi, L.; Rodriguez-Iturbe, I.

    The reduction of soil moisture content during droughts lowers the plant water potential and decreases transpiration; this in turn causes a reduction of cell turgor and relative water content which brings about a sequence of damages of increasing seriousness. A review of the literature on plant physiology and water stress shows that vegetation water stress can be assumed to start at the soil moisture level corresponding to incipient stomatal closure and reach a maximum intensity at the wilting point. The mean crossing properties of these soil moisture levels crucial for water stress are derived analytically for the stochastic model of soil moisture dynamics described in Part II (F. Laio, A. Porporato, L. Ridolfi, I. Rodriguez-Iturbe. Adv. Water Res. 24 (7) (2001) 707-723). These properties are then used to propose a measure of vegetation water stress which combines the mean intensity, duration, and frequency of periods of soil water deficit. The characteristics of vegetation water stress are then studied under different climatic conditions, showing how the interplay between plant, soil, and environment can lead to optimal conditions for vegetation.

  15. Survival strategies of plants during water stress

    International Nuclear Information System (INIS)

    Scheuermann, R.; Stuhlfauth, T.; Sueltemeyer, D.; Fock, H.

    1989-01-01

    Fluorescence and gas exchange of bean, maize, sunflower and wooly foxglove were simultaneously measured at 250 μmol quanta/m 2 /s. Under severe water stresses conditions about 40% of the photochemical energy was converted to heat at PS II. This is interpreted as a protective mechanism against photoinhibitory damage when net CO 2 uptake is reduced by about 70%. After 14 CO 2 gas exchange, only in bean was a homogeneous distribution of radioactivity over the leaf observed. In all other plants we found a patchy distribution of regions with either an intensive or a reduced gas exchange. We conclude that CO 2 -recycling (photorespiration and reassimilation) behind closed stomata also contributed to energy dissipation under severe stress conditions

  16. Global water cycle: geochemistry and environment

    National Research Council Canada - National Science Library

    Berner, Elizabeth Kay; Berner, Robert A

    1987-01-01

    .... The book provides an integrated approach to global geochemistry and environmental problems and introduces the reader to some fundamental concepts of geology, oceanography, meteorology, environmental...

  17. eWaterCycle: A global operational hydrological forecasting model

    Science.gov (United States)

    van de Giesen, Nick; Bierkens, Marc; Donchyts, Gennadii; Drost, Niels; Hut, Rolf; Sutanudjaja, Edwin

    2015-04-01

    Development of an operational hyper-resolution hydrological global model is a central goal of the eWaterCycle project (www.ewatercycle.org). This operational model includes ensemble forecasts (14 days) to predict water related stress around the globe. Assimilation of near-real time satellite data is part of the intended product that will be launched at EGU 2015. The challenges come from several directions. First, there are challenges that are mainly computer science oriented but have direct practical hydrological implications. For example, we aim to make use as much as possible of existing standards and open-source software. For example, different parts of our system are coupled through the Basic Model Interface (BMI) developed in the framework of the Community Surface Dynamics Modeling System (CSDMS). The PCR-GLOBWB model, built by Utrecht University, is the basic hydrological model that is the engine of the eWaterCycle project. Re-engineering of parts of the software was needed for it to run efficiently in a High Performance Computing (HPC) environment, and to be able to interface using BMI, and run on multiple compute nodes in parallel. The final aim is to have a spatial resolution of 1km x 1km, which is currently 10 x 10km. This high resolution is computationally not too demanding but very memory intensive. The memory bottleneck becomes especially apparent for data assimilation, for which we use OpenDA. OpenDa allows for different data assimilation techniques without the need to build these from scratch. We have developed a BMI adaptor for OpenDA, allowing OpenDA to use any BMI compatible model. To circumvent memory shortages which would result from standard applications of the Ensemble Kalman Filter, we have developed a variant that does not need to keep all ensemble members in working memory. At EGU, we will present this variant and how it fits well in HPC environments. An important step in the eWaterCycle project was the coupling between the hydrological and

  18. Toward an Improved Understanding of the Global Fresh Water Budget

    Science.gov (United States)

    Hildebrand, Peter H.

    2005-01-01

    The major components of the global fresh water cycle include the evaporation from the land and ocean surfaces, precipitation onto the Ocean and land surfaces, the net atmospheric transport of water from oceanic areas over land, and the return flow of water from the land back into the ocean. The additional components of oceanic water transport are few, principally, the mixing of fresh water through the oceanic boundary layer, transport by ocean currents, and sea ice processes. On land the situation is considerably more complex, and includes the deposition of rain and snow on land; water flow in runoff; infiltration of water into the soil and groundwater; storage of water in soil, lakes and streams, and groundwater; polar and glacial ice; and use of water in vegetation and human activities. Knowledge of the key terms in the fresh water flux budget is poor. Some components of the budget, e.g. precipitation, runoff, storage, are measured with variable accuracy across the globe. We are just now obtaining precise measurements of the major components of global fresh water storage in global ice and ground water. The easily accessible fresh water sources in rivers, lakes and snow runoff are only adequately measured in the more affluent portions of the world. presents proposals are suggesting methods of making global measurements of these quantities from space. At the same time, knowledge of the global fresh water resources under the effects of climate change is of increasing importance and the human population grows. This paper provides an overview of the state of knowledge of the global fresh water budget, evaluating the accuracy of various global water budget measuring and modeling techniques. We review the measurement capabilities of satellite instruments as compared with field validation studies and modeling approaches. Based on these analyses, and on the goal of improved knowledge of the global fresh water budget under the effects of climate change, we suggest

  19. A Global Rapid Integrated Monitoring System for Water Cycle and Water Resource Assessment (Global-RIMS)

    Science.gov (United States)

    Roads, John; Voeroesmarty, Charles

    2005-01-01

    The main focus of our work was to solidify underlying data sets, the data processing tools and the modeling environment needed to perform a series of long-term global and regional hydrological simulations leading eventually to routine hydrometeorological predictions. A water and energy budget synthesis was developed for the Mississippi River Basin (Roads et al. 2003), in order to understand better what kinds of errors exist in current hydrometeorological data sets. This study is now being extended globally with a larger number of observations and model based data sets under the new NASA NEWS program. A global comparison of a number of precipitation data sets was subsequently carried out (Fekete et al. 2004) in which it was further shown that reanalysis precipitation has substantial problems, which subsequently led us to the development of a precipitation assimilation effort (Nunes and Roads 2005). We believe that with current levels of model skill in predicting precipitation that precipitation assimilation is necessary to get the appropriate land surface forcing.

  20. Enhancing the water management schemes of H08 global hydrological model to attribute human water use to six major water sources

    Science.gov (United States)

    Hanasaki, N.; Yoshikawa, S.; Pokhrel, Y. N.; Kanae, S.

    2017-12-01

    Humans abstract water from various sources to sustain their livelihood and society. Some global hydrological models (GHMs) include explicit schemes of human water management, but the representation and performance of these schemes remain limited. We substantially enhanced the human water management schemes of the H08 GHM by incorporating the latest data and techniques. The model enables us to estimate water abstraction from six major water sources, namely, river flow regulated by global reservoirs (i.e., reservoirs regulating the flow of the world's major rivers), aqueduct water transfer, local reservoirs, seawater desalination, renewable groundwater, and nonrenewable groundwater. All the interactions were simulated in a single computer program and the water balance was always strictly closed at any place and time during the simulation period. Using this model, we first conducted a historical global hydrological simulation at a spatial resolution of 0.5 x 0.5 degree to specify the sources of water for humanity. The results indicated that, in 2000, of the 3628 km3yr-1 global freshwater requirement, 2839 km3yr-1 was taken from surface water and 789 km3yr-1 from groundwater. Streamflow, aqueduct water transfer, local reservoirs, and seawater desalination accounted for 1786, 199, 106, and 1.8 km3yr-1 of the surface water, respectively. The remaining 747 km3yr-1 freshwater requirement was unmet, or surface water was not available when and where it was needed in our simulation. Renewable and nonrenewable groundwater accounted for 607 and 182 km3yr-1 of the groundwater total, respectively. Second, we evaluated the water stress using our simulations and contrasted it with earlier global assessments based on empirical water scarcity indicators, namely, the Withdrawal to Availability ratio and the Falkenmark index (annual renewable water resources per capita). We found that inclusion of water infrastructures in our model diminished water stress in some parts of the world, on

  1. Remote sensing of water and nitrogen stress in broccoli

    Science.gov (United States)

    Elsheikha, Diael-Deen Mohamed

    Remote sensing is being used in agriculture for crop management. Ground based remote sensing data acquisition system was used for collection of high spatial and temporal resolution data for irrigated broccoli crop. The system was composed of a small cart that ran back and forth on a rail system that was mounted on a linear move irrigation system. The cart was equipped with a sensor that had 4 discrete wavelengths; 550 nm, 660 nm, 720 nm, and 810 nm, and an infrared thermometer, all had 10 nm bandwidth. A global positioning system was used to indicate the cart position. The study consisted of two parts; the first was to evaluate remotely sensed reflectance and indices in broccoli during the growing season, and determine whether remotely sensed indices or standard deviation of indices can distinguish between nitrogen and water stress in broccoli, and the second part of the study was to evaluate remotely sensed indices and standard deviation of remotely sensed indices in broccoli during daily changes in solar zenith angle. Results indicated that nitrogen was detected using Ratio Vegetation index, RVI, Normalized Difference Vegetation Index, NDVI, Canopy Chlorophyll Concentration Index, CCCI, and also using the reflectance in the Near-Infrared, NIR, bands. The Red reflectance band capability of showing stress was not as clear as the previous indices and bands reflectance. The Canopy Chlorophyll Concentration Index, CCCI, was the most successful index. The Crop Water Stress Index was able to detect water stress but it was highly affected by the solar zenith angle change along the day.

  2. Water security-National and global issues

    Science.gov (United States)

    Tindall, James A.; Campbell, Andrew A.

    2010-01-01

    Potable or clean freshwater availability is crucial to life and economic, environmental, and social systems. The amount of freshwater is finite and makes up approximately 2.5 percent of all water on the Earth. Freshwater supplies are small and randomly distributed, so water resources can become points of conflict. Freshwater availability depends upon precipitation patterns, changing climate, and whether the source of consumed water comes directly from desalination, precipitation, or surface and (or) groundwater. At local to national levels, difficulties in securing potable water sources increase with growing populations and economies. Available water improves living standards and drives urbanization, which increases average water consumption per capita. Commonly, disruptions in sustainable supplies and distribution of potable water and conflicts over water resources become major security issues for Government officials. Disruptions are often influenced by land use, human population, use patterns, technological advances, environmental impacts, management processes and decisions, transnational boundaries, and so forth.

  3. Wind Stress Variability Observed Over Coastal Waters

    Science.gov (United States)

    Ortiz-Suslow, D. G.; Haus, B. K.; Laxague, N.; Williams, N. J.; Graber, H. C.

    2016-02-01

    The wind stress on the ocean surface generates waves, drives currents, and enhances gas exchange; and a significant amount of work has been done to characterize the air-sea momentum flux in terms of bulk oceanographic and atmospheric parameters. However, the majority of this work to develop operational algorithms has been focused on the deep ocean and the suitability of these methods in the coastal regime has not been evaluated. The findings from a two-part field campaign will be presented which highlight the divergence of nearshore wind stress observations from conventional, deep water results. The first set of data comes from a coastal region near a relatively small, natural tidal inlet. A high degree of spatial variability was observed in both the wind stress magnitude and direction, suggestive of coastal processes (e.g., depth-limited wave affects and horizontal current shear) modulating the momentum flux from the atmosphere to the ocean surface. These shallow-water processes are typically not accounted for in conventional parameterizations. Across the experimental domain and for a given wind speed, the stress magnitude was found to be nearly 2.5 times that predicted by conventional methods; also, a high propensity for stress steering off the mean azimuthal wind direction (up to ±70 degrees) was observed and linked to horizontal current gradients produced by the tidal inlet. The preliminary findings from a second data set taken in the vicinity of the macrotidal Columbia River Mouth will also be presented. Compared to the first data set, a similar degree of variability is observed here, but the processes responsible for this are present at a much larger scale. Specifically, the Columbia River Mouth observations were made in the presence of significant swell wave energy and during periods of very high estuarine discharge. The relative angle between the wind and swell direction is expected to be significant with regards to the observed momentum flux. Also, these

  4. Is physical water scarcity a new phenomenon? Global assessment of water shortage over the last two millennia

    International Nuclear Information System (INIS)

    Kummu, Matti; Varis, Olli; Ward, Philip J; De Moel, Hans

    2010-01-01

    In this letter we analyse the temporal development of physical population-driven water scarcity, i.e. water shortage, over the period 0 AD to 2005 AD. This was done using population data derived from the HYDE dataset, and water resource availability based on the WaterGAP model results for the period 1961-90. Changes in historical water resources availability were simulated with the STREAM model, forced by climate output data of the ECBilt-CLIO-VECODE climate model. The water crowding index, i.e. Falkenmark water stress indicator, was used to identify water shortage in 284 sub-basins. Although our results show a few areas with moderate water shortage (1000-1700 m 3 /capita/yr) around the year 1800, water shortage began in earnest at around 1900, when 2% of the world population was under chronic water shortage ( 3 /capita/yr). By 1960, this percentage had risen to 9%. From then on, the number of people under water shortage increased rapidly to the year 2005, by which time 35% of the world population lived in areas with chronic water shortage. In this study, the effects of changes in population on water shortage are roughly four times more important than changes in water availability as a result of long-term climatic change. Global trends in adaptation measures to cope with reduced water resources per capita, such as irrigated area, reservoir storage, groundwater abstraction, and global trade of agricultural products, closely follow the recent increase in global water shortage.

  5. Advances in Global Water Cycle Science Made Possible by Global Precipitation Mission (GPM)

    Science.gov (United States)

    Smith, Eric A.; Starr, David OC. (Technical Monitor)

    2001-01-01

    Within this decade the internationally sponsored Global Precipitation Mission (GPM) will take an important step in creating a global precipitation observing system from space. One perspective for understanding the nature of GPM is that it will be a hierarchical system of datastreams from very high caliber combined dual frequency radar/passive microwave (PMW) rain-radiometer retrievals, to high caliber PMW rain-radiometer only retrievals, and on to blends of the former datastreams with other less-high caliber PMW-based and IR-based rain retrievals. Within the context of NASA's role in global water cycle science and its own Global Water & Energy Cycle (GWEC) program, GPM is the centerpiece mission for improving our understanding of the global water cycle from a space-based measurement perspective. One of the salient problems within our current understanding of the global water and energy cycle is determining whether a change in the rate of the water cycle is accompanying changes in global temperature. As there are a number of ways in which to define a rate-change of the global water cycle, it is not entirely clear as to what constitutes such a determination, This paper presents an overview of the Global Precipitation Mission and how its datasets can be used in a set of quantitative tests within the framework of the oceanic and continental water budget equations to determine comprehensively whether substantive rate changes do accompany perturbations in global temperatures and how such rate changes manifest themselves in both water storage and water flux transport processes.

  6. Rethinking Global Water Governance for the 21st Century

    Science.gov (United States)

    Ajami, N. K.; Cooley, H.

    2012-12-01

    Growing pressure on the world's water resources is having major impacts on our social and economic well-being. According to the United Nations, today, at least 1.1 billion people do not have access to clean drinking water. Pressures on water resources are likely to continue to worsen in response to decaying and crumbling infrastructure, continued population growth, climate change, degradation of water quality, and other challenges. If these challenges are not addressed, they pose future risks for many countries around the world, making it urgent that efforts are made to understand both the nature of the problems and the possible solutions that can effectively reduce the associated risks. There is growing understanding of the need to rethink governance to meet the 21st century water challenges. More and more water problems extend over traditional national boundaries and to the global community and the types and numbers of organizations addressing water issues are large and growing. Economic globalization and transnational organizations and activities point to the need for improving coordination and integration on addressing water issues, which are increasingly tied to food and energy security, trade, global climate change, and other international policies. We will present some of the key limitations of global water governance institutions and provide recommendations for improving these institutions to address 21st century global water challenges more effectively.

  7. Global operational hydrological forecasts through eWaterCycle

    Science.gov (United States)

    van de Giesen, Nick; Bierkens, Marc; Donchyts, Gennadii; Drost, Niels; Hut, Rolf; Sutanudjaja, Edwin

    2015-04-01

    Central goal of the eWaterCycle project (www.ewatercycle.org) is the development of an operational hyper-resolution hydrological global model. This model is able to produce 14 day ensemble forecasts based on a hydrological model and operational weather data (presently NOAA's Global Ensemble Forecast System). Special attention is paid to prediction of situations in which water related issues are relevant, such as floods, droughts, navigation, hydropower generation, and irrigation stress. Near-real time satellite data will be assimilated in the hydrological simulations, which is a feature that will be presented for the first time at EGU 2015. First, we address challenges that are mainly computer science oriented but have direct practical hydrological implications. An important feature in this is the use of existing standards and open-source software to the maximum extent possible. For example, we use the Community Surface Dynamics Modeling System (CSDMS) approach to coupling models (Basic Model Interface (BMI)). The hydrological model underlying the project is PCR-GLOBWB, built by Utrecht University. This is the motor behind the predictions and state estimations. Parts of PCR-GLOBWB have been re-engineered to facilitate running it in a High Performance Computing (HPC) environment, run parallel on multiple nodes, as well as to use BMI. Hydrological models are not very CPU intensive compared to, say, atmospheric models. They are, however, memory hungry due to the localized processes and associated effective parameters. To accommodate this memory need, especially in an ensemble setting, a variation on the traditional Ensemble Kalman Filter was developed that needs much less on-chip memory. Due to the operational nature, the coupling of the hydrological model with hydraulic models is very important. The idea is not to run detailed hydraulic routing schemes over the complete globe but to have on-demand simulation prepared off-line with respect to topography and

  8. Earth Observations for Global Water Security

    Science.gov (United States)

    Lawford, Richard; Strauch, Adrian; Toll, David; Fekete, Balazs; Cripe, Douglas

    2013-01-01

    The combined effects of population growth, increasing demands for water to support agriculture, energy security, and industrial expansion, and the challenges of climate change give rise to an urgent need to carefully monitor and assess trends and variations in water resources. Doing so will ensure that sustainable access to adequate quantities of safe and useable water will serve as a foundation for water security. Both satellite and in situ observations combined with data assimilation and models are needed for effective, integrated monitoring of the water cycle's trends and variability in terms of both quantity and quality. On the basis of a review of existing observational systems, we argue that a new integrated monitoring capability for water security purposes is urgently needed. Furthermore, the components for this capability exist and could be integrated through the cooperation of national observational programmes. The Group on Earth Observations should play a central role in the design, implementation, management and analysis of this system and its products.

  9. Chronic water stress reduces tree growth and the carbon sink of deciduous hardwood forests.

    Science.gov (United States)

    Brzostek, Edward R; Dragoni, Danilo; Schmid, Hans Peter; Rahman, Abdullah F; Sims, Daniel; Wayson, Craig A; Johnson, Daniel J; Phillips, Richard P

    2014-08-01

    Predicted decreases in water availability across the temperate forest biome have the potential to offset gains in carbon (C) uptake from phenology trends, rising atmospheric CO2 , and nitrogen deposition. While it is well established that severe droughts reduce the C sink of forests by inducing tree mortality, the impacts of mild but chronic water stress on forest phenology and physiology are largely unknown. We quantified the C consequences of chronic water stress using a 13-year record of tree growth (n = 200 trees), soil moisture, and ecosystem C balance at the Morgan-Monroe State Forest (MMSF) in Indiana, and a regional 11-year record of tree growth (n > 300 000 trees) and water availability for the 20 most dominant deciduous broadleaf tree species across the eastern and midwestern USA. We show that despite ~26 more days of C assimilation by trees at the MMSF, increasing water stress decreased the number of days of wood production by ~42 days over the same period, reducing the annual accrual of C in woody biomass by 41%. Across the deciduous forest region, water stress induced similar declines in tree growth, particularly for water-demanding 'mesophytic' tree species. Given the current replacement of water-stress adapted 'xerophytic' tree species by mesophytic tree species, we estimate that chronic water stress has the potential to decrease the C sink of deciduous forests by up to 17% (0.04 Pg C yr(-1) ) in the coming decades. This reduction in the C sink due to mesophication and chronic water stress is equivalent to an additional 1-3 days of global C emissions from fossil fuel burning each year. Collectively, our results indicate that regional declines in water availability may offset the growth-enhancing effects of other global changes and reduce the extent to which forests ameliorate climate warming. © 2014 John Wiley & Sons Ltd.

  10. Water within the Shared Socioeconomic Pathways: Constraints and the Impact on Future Global Change Scenarios

    Science.gov (United States)

    Graham, N. T.; Hejazi, M. I.; Davies, E. G.; Calvin, K. V.; Kim, S. H.; Miralles-Wilhelm, F.

    2017-12-01

    The Shared Socioeconomic Pathways (SSPs) represent the next generation of future global change scenarios and their inclusion in the Coupled Model Intercomparison Project Phase 6 (CMIP6) scenarios reinforces the importance of a complete understanding of the SSPs. This study uses the Global Change Assessment Model (GCAM) to investigate the effects of limited water supplies on future withdrawals at regional and water basin scales across all SSPs in combination with various climate mitigation scenarios. Water supply is calculated using a global hydrologic model and water data from five ISI-MIP models across the four RCP scenarios. When water constraints are incorporated, our results show that water withdrawals are reduced by as much as 40% across all SSP scenarios without climate policies. As climate policies are imposed and become more stringent, water withdrawals increase in regions already affected by water stress in order to allow for greater biomass production. The results of this research show the importance of including water resource constraints within the SSP scenarios for establishing water withdrawal scenarios under a wide range of scenarios including different climate policies. The results will also provide data products - such as gridded land use and water demand estimates - of potential interest to the impact, adaptation, and vulnerability community following the SSP scenarios.

  11. Critical water stress levels in Pinus patula seedlings and their ...

    African Journals Online (AJOL)

    Critical water stress levels in Pinus patula seedlings and their relation to measures of seedling morphology. ... Southern Forests: a Journal of Forest Science ... A pot trial was implemented to determine the effect of soil water stress following transplanting on shoot water potential and stomatal conductance of Pinus patula ...

  12. Stress, work and mental health: a global perspective.

    Science.gov (United States)

    deVries, Marten W; Wilkerson, Bill

    2003-02-01

    The United Nations, WHO and the World Bank have called the current prevalence rate of neuro-psychiatric disorder approaches of 1 in 4 individuals worldwide and 'unheralded public health crisis'. Rates are driven by an early onset, high impairment and high chronicity of these disorders. Most importantly, detection and treatment rates are low, estimated at les than 10% worldwide resulting in 500 million people underserved. The related economic costs soared in 1999 to 120 billion dollars in Europe and North America, with over 60 billion dollars assigned to stress related disorders. Contributing factors are bio-psycho-social and include rapid social change as well as the time compression of modern life resulting in the experience of increased work-life stress that parallels a decade long intensification of activities in the workplace. Coping with the requirements of the new economy of mental performance has lagged behind at many individual and social levels as we cling to adjustments made during the industrial economy of the last century. A climate of transition, and more recently, terror and fear have stressed the landscape of mental health and work already ravaged by the destructive forces of stigma. This presentation will examine the other side of prosperity from the point of view of stress in the workplace as two global problems converge at this time in history, the escalation of neuro-psychiatric disorders and the increasing dependence on the mental faculties of the world's citizens. In this paper we also discuss how the international community can work together to help reduce the burden of mental disorders worldwide and sketch the implications for research and policy. Ultimately the media will need to be enlisted to educate the public on the value of investments in mental health.

  13. Water for bioenergy: A global analysis

    NARCIS (Netherlands)

    Gerbens-Leenes, Winnie; Hoekstra, Arjen Ysbert; van der Meer, Theodorus H.; Gasparatos, A.; Stromberg, P.

    2012-01-01

    Agriculture is by far the largest water user. This chapter reviews studies on the water footprints (WFs) of bioenergy (in the form of bioethanol, biodiesel, and heat and electricity produced from biomass) and compares their results with the WFs of fossil energy and other types of renewables (wind

  14. The role of scarcity in global virtual water flows

    OpenAIRE

    Lenzen, Manfred; Bhaduri, Anik; Moran, Daniel; Kanemoto, Keiichiro; Bekchanov, Maksud

    2012-01-01

    Recent analyses of the evolution and structure of trade in virtual water revealed that the number of trade connections and volume of virtual water trade have more than doubled over the past two decades, and that developed countries increasingly draw on the rest of the world to alleviate the pressure on their domestic water resources. Our work builds on these studies, but fills three important gaps in the research on global virtual water trade. First, we note that in previous studies virtual w...

  15. Effects of water stress on germination of Pinus nigra Arnold. seeds

    International Nuclear Information System (INIS)

    Topacoglu, O.; Sevik, H.; Akkuzu, E.

    2016-01-01

    Climate change, global warming and the deterioration of related environmental conditions cause an important problem for forest tree species. For this reason, it is necessary to determine the response of trees to these conditions. The Objective of this study was to investigate the effects of water stress on seed germination of fifteen Pinus nigra Arnold. provenances in Turkey. For this purpose, the water stresses between 0 and -8.0 bars were obtained using polyethylene glycol-6000 (PEG) solutions. Seeds were kept for 35 days at 20 ± 0.5 degree C. In this study, significant variations between the provenances were found. Ankara Uluhan ( percent 95, 08) and Isparta Tota ( percent 85, 41) provenances at -8.0 bars having the highest cumulative germination percentages were the most resistant provenances against the water stress. This study has shown that the water stress reduced the germination speed, germination percentage and germination value. (author)

  16. Governing Non-Potable Water-Reuse to Alleviate Water Stress: The Case of Sabadell, Spain

    Directory of Open Access Journals (Sweden)

    Marketa Šteflová

    2018-06-01

    Full Text Available The world will experience an estimated 40% freshwater supply shortage by 2030, converting water scarcity into one of the principal global challenges that modern society faces. Urban water reuse is recognized as a promising and necessary measure to alleviate the growing water stress in many regions. The transformation to widespread application of water-reuse systems requires major changes in the way water is governed, and countries such as Spain already find themselves involved in this process. Through the systematic assessment of the city of Sabadell (Spain, we aim to identify the main barriers, opportunities and transferable lessons that can enhance governance capacity to implement systems for non-potable reuse of treated wastewater in cities. It was found that continuous learning, the availability and quality of information, the level of knowledge, and strong agents of change are the main capacity-building priorities. On the other hand, awareness, multilevel network potential and implementing capacity are already well-established. It is concluded that in order to undertake a widespread application of water-reuse practices, criteria examining water quality according to its use need to be developed independently of the water’s origin. The development and implementation of such a legislative frame should be based on the experience of local water-reuse practices and continuous evaluation. Finally, the need for public engagement and adequate pricing mechanisms are emphasized.

  17. Global Water Governance in the Context of Global and Multilevel Governance: Its Need, Form, and Challenges

    Directory of Open Access Journals (Sweden)

    Joyeeta Gupta

    2013-12-01

    Full Text Available To complement this Special Feature on global water governance, we focused on a generic challenge at the global level, namely, the degree to which water issues need to be dealt with in a centralized, concentrated, and hierarchical manner. We examined water ecosystem services and their impact on human well-being, the role of policies, indirect and direct drivers in influencing these services, and the administrative level(s at which the provision of services and potential trade-offs can be dealt with. We applied a politics of scale perspective to understand motivations for defining a problem at the global or local level and show that the multilevel approach to water governance is evolving and inevitable. We argue that a centralized overarching governance system for water is unlikely and possibly undesirable; however, there is a need for a high-level think tank and leadership to develop a cosmopolitan perspective to promote sustainable water development.

  18. Modeling global distribution of agricultural insecticides in surface waters

    International Nuclear Information System (INIS)

    Ippolito, Alessio; Kattwinkel, Mira; Rasmussen, Jes J.; Schäfer, Ralf B.; Fornaroli, Riccardo; Liess, Matthias

    2015-01-01

    Agricultural insecticides constitute a major driver of animal biodiversity loss in freshwater ecosystems. However, the global extent of their effects and the spatial extent of exposure remain largely unknown. We applied a spatially explicit model to estimate the potential for agricultural insecticide runoff into streams. Water bodies within 40% of the global land surface were at risk of insecticide runoff. We separated the influence of natural factors and variables under human control determining insecticide runoff. In the northern hemisphere, insecticide runoff presented a latitudinal gradient mainly driven by insecticide application rate; in the southern hemisphere, a combination of daily rainfall intensity, terrain slope, agricultural intensity and insecticide application rate determined the process. The model predicted the upper limit of observed insecticide exposure measured in water bodies (n = 82) in five different countries reasonably well. The study provides a global map of hotspots for insecticide contamination guiding future freshwater management and conservation efforts. - Highlights: • First global map on insecticide runoff through modelling. • Model predicts upper limit of insecticide exposure when compared to field data. • Water bodies in 40% of global land surface may be at risk of adverse effects. • Insecticide application rate, terrain slope and rainfall main drivers of exposure. - We provide the first global map on insecticide runoff to surface water predicting that water bodies in 40% of global land surface may be at risk of adverse effects

  19. Advances in Understanding Global Water Cycle with Advent of Global Precipitation Measurement (GPM) Mission

    Science.gov (United States)

    Smith, Eric A.; Starr, David (Technical Monitor)

    2002-01-01

    Within this decade the internationally organized Global Precipitation Measurement (GPM) Mission will take an important step in creating a global precipitation observing system from space. One perspective for understanding the nature of GPM is that it will be a hierarchical system of datastreams beginning with very high caliber combined dual frequency radar/passive microwave (PMW) rain-radiometer retrievals, to high caliber PMW rain-radiometer only retrievals, and then on to blends of the former datastreams with additional lower-caliber PMW-based and IR-based rain retrievals. Within the context of the now emerging global water & energy cycle (GWEC) programs of a number of research agencies throughout the world, GPM serves as a centerpiece space mission for improving our understanding of the global water cycle from a global measurement perspective. One of the salient problems within our current understanding of the global water and energy cycle is determining whether a change in the rate of the water cycle is accompanying changes in climate, e.g., climate warming. As there are a number of ways in which to define a rate-change of the global water cycle, it is not entirely clear as to what constitutes such a determination. This paper presents an overview of the GPM Mission and how its observations can be used within the framework of the oceanic and continental water budget equations to determine whether a given perturbation in precipitation is indicative of an actual rate change in the global water cycle, consistent with required responses in water storage and/or water flux transport processes, or whether it is the natural variability of a fixed rate cycle.

  20. Facing global environmental change. Environmental, human, energy, food, health and water security concepts

    Energy Technology Data Exchange (ETDEWEB)

    Brauch, Hans Guenter [Freie Univ. Berlin (Germany). Dept. of Political and Social Sciences; United Nations Univ., Bonn (DE). Inst. for Environment and Human Security (UNU-EHS); AFES-Press, Mosbach (Germany); Oswald Spring, Ursula [National Univ. of Mexico (UNAM), Cuernavaca, MOR (MX). Centro Regional de Investigaciones Multidiscipinarias (CRIM); United Nations Univ., Bonn (DE). Inst. for Environment and Human Security (UNU-EHS); Grin, John [Amsterdam Univ. (Netherlands). Amsterdam School for Social Science Research; Mesjasz, Czeslaw [Cracow Univ. of Economics (Poland). Faculty of Management; Kameri-Mbote, Patricia [Nairobi Univ. (Kenya). School of Law; International Environmental Law Research Centre, Nairobi (Kenya); Behera, Navnita Chadha [Jamia Millia Islamia Univ., New Delhi (India). Nelson Mandela Center for Peace and Conflict Resolution; Chourou, Bechir [Tunis-Carthage Univ., Hammam-Chatt (Tunisia); Krummenacher, Heinz (eds.) [swisspeace, Bern (Switzerland). FAST International

    2009-07-01

    This policy-focused, global and multidisciplinary security handbook on Facing Global Environmental Change addresses new security threats of the 21st century posed by climate change, desertification, water stress, population growth and urbanization. These security dangers and concerns lead to migration, crises and conflicts. They are on the agenda of the UN, OECD, OSCE, NATO and EU. In 100 chapters, 132 authors from 49 countries analyze the global debate on environmental, human and gender, energy, food, livelihood, health and water security concepts and policy problems. In 10 parts they discuss the context and the securitization of global environmental change and of extreme natural and societal outcomes. They suggest a new research programme to move from knowledge to action, from reactive to proactive policies and to explore the opportunities of environ-mental cooperation for a new peace policy. (orig.)

  1. Water stress, water salience, and the implications for water supply planning

    Science.gov (United States)

    Garcia, M. E.; Islam, S.

    2017-12-01

    Effectively addressing the water supply challenges posed by urbanization and climate change requires a holistic understanding of the water supply system, including the impact of human behavior on system dynamics. Decision makers have limits to available information and information processing capacity, and their attention is not equally distributed among risks. The salience of a given risk is higher when increased attention is directed to it and though perceived risk may increase, real risk does not change. Relevant to water supply planning is how and when water stress results in an increased salience of water risks. This work takes a socio-hydrological approach to develop a water supply planning model that includes water consumption as an endogenous variable, in the context of Las Vegas, NV. To understand the benefits and limitations of this approach, this model is compared to a traditional planning model that uses water consumption scenarios. Both models are applied to project system reliability and water stress under four streamflow and demographic scenarios, and to assess supply side responses to changing conditions. The endogenous demand model enables the identification of feedback between both supply and demand management decisions on future water consumption and system performance. This model, while specific to the Las Vegas case, demonstrates a prototypical modeling framework capable of examining water-supply demand interactions by incorporating water stress driven conservation.

  2. Global gray water footprint and water pollution levels related to anthropogenic nitrogen loads to fresh water

    NARCIS (Netherlands)

    Mekonnen, Mesfin; Hoekstra, Arjen Ysbert

    2015-01-01

    This is the first global assessment of nitrogen-related water pollution in river basins with a specification of the pollution by economic sector, and by crop for the agricultural sector. At a spatial resolution of 5 by 5 arc minute, we estimate anthropogenic nitrogen (N) loads to freshwater,

  3. Collection of Condensate Water: Global Potential and Water Quality Impacts

    KAUST Repository

    Loveless, Kolin Joseph; Farooq, Aamir; Ghaffour, NorEddine

    2012-01-01

    . Technologies that can supply fresh water at a reduced cost are therefore becoming increasingly important and the impact of such technologies can be substantial. This paper considers the collection of condensate water from large air conditioning units as a

  4. Impacts of Wind Stress Changes on the Global Heat Transport, Baroclinic Instability, and the Thermohaline Circulation

    Directory of Open Access Journals (Sweden)

    Jeferson Prietsch Machado

    2016-01-01

    Full Text Available The wind stress is a measure of momentum transfer due to the relative motion between the atmosphere and the ocean. This study aims to investigate the anomalous pattern of atmospheric and oceanic circulations due to 50% increase in the wind stress over the equatorial region and the Southern Ocean. In this paper we use a coupled climate model of intermediate complexity (SPEEDO. The results show that the intensification of equatorial wind stress causes a decrease in sea surface temperature in the tropical region due to increased upwelling and evaporative cooling. On the other hand, the intensification of wind stress over the Southern Ocean induces a regional increase in the air and sea surface temperatures which in turn leads to a reduction in Antarctic sea ice thickness. This occurs in association with changes in the global thermohaline circulation strengthening the rate of Antarctic Bottom Water formation and a weakening of the North Atlantic Deep Water. Moreover, changes in the Southern Hemisphere thermal gradient lead to modified atmospheric and oceanic heat transports reducing the storm tracks and baroclinic activity.

  5. Assessment of global grey water footprint of major food crops

    Science.gov (United States)

    Yang, Hong; Liu, Wenfeng; Antonelli, Marta

    2016-04-01

    Agricultural production is one of the major sources of water pollution in the world. This is closely related to the excess application of fertilizers. Leaching of N and P to water bodies has caused serious degradation of water quality in many places. With the persistent increase in the demand for agricultural products, agricultural intensification evident during the past decades will continue in the future. This will lead to further increase in fertilizer application and consequently water pollution. Grey water footprint is a measure of the intensity of water pollution caused by water use for human activities. It is defined as the volume of water that is required to assimilate a load of pollutants to a freshwater body, based on natural background concentrations and water quality standards. This study conducts a global assessment of grey water footprint for major cereal crops, wheat, maize and rice. A crop model, Python-based EPIC (PEPIT), is applied to quantify the leaching of N and P from the fertilizer application in the three crops on a global scale with 0.5 degree spatial resolution. The hotspots of leaching are identified. The results suggest that, based on the definition and method of grey water footprint proposed by the World Water Footprint Network, the grey water footprint in many parts of the world has exceeded their total water resources availability. This indicates the seriousness of water pollution caused by agricultural production. However, the situation may also call for the development of a realistic measurement of grey water footprint which is more pertinent to water resources management. This paper proposes some alternatives in measuring grey water footprint and also discusses incorporation of grey water footprint assessment into water policy formulation and river basins plan development.

  6. Watch: Current knowledge of the terrestrial Global Water Cycle"

    NARCIS (Netherlands)

    Harding, R.; Best, M.; Hagemann, S.; Kabat, P.; Tallaksen, L.M.; Warnaars, T.; Wiberg, D.; Weedon, G.P.; Lanen, van H.A.J.; Ludwig, F.; Haddeland, I.

    2011-01-01

    Water-related impacts are among the most important consequences of increasing greenhouse gas concentrations. Changes in the global water cycle will also impact the carbon and nutrient cycles and vegetation patterns. There is already some evidence of increasing severity of floods and droughts and

  7. Global Water Availability and Requirements for Future Food Production

    NARCIS (Netherlands)

    Gerten, D.; Heinke, J.; Hoff, H.; Biemans, H.; Fader, M.; Waha, K.

    2011-01-01

    This study compares, spatially explicitly and at global scale, per capita water availability and water requirements for food production presently (1971-2000) and in the future given climate and population change (2070-99). A vegetation and hydrology model Lund-Potsdam-Jena managed Land (LPJmL) was

  8. Global River Discharge and Water Temperature under Climate Change

    NARCIS (Netherlands)

    Vliet, van M.T.H.; Franssen, W.H.P.; Yearsley, J.R.; Ludwig, F.; Haddeland, I.; Lettenmaier, D.P.; Kabat, P.

    2013-01-01

    Climate change will affect hydrologic and thermal regimes of rivers, having a direct impact on freshwater ecosystems and human water use. Here we assess the impact of climate change on global river flows and river water temperatures, and identify regions that might become more critical for

  9. The Global Enery and Water Cycle Experiment Science Strategy

    Science.gov (United States)

    Chahine, M. T.

    1997-01-01

    The distribution of water in the atmosphere and at the surface of the Earth is the most influential factor regulating our environment, not only because water is essential for life but also because through phase transitions it is the main energy source that control clouds and radiation and drives the global circulation of the atmosphere.

  10. Collection of Condensate Water: Global Potential and Water Quality Impacts

    KAUST Repository

    Loveless, Kolin Joseph

    2012-12-28

    Water is a valuable resource throughout the world, especially in hot, dry climates and regions experiencing significant population growth. Supplies of fresh water are complicated by the economic and political conditions in many of these regions. Technologies that can supply fresh water at a reduced cost are therefore becoming increasingly important and the impact of such technologies can be substantial. This paper considers the collection of condensate water from large air conditioning units as a possible method to alleviate water scarcity issues. Using the results of a climate model that tested data collected from 2000 to 2010, we have identified areas in the world with the greatest collection potential. We gave special consideration to areas with known water scarcities, including the coastal regions of the Arabian Peninsula, Sub-Saharan Africa and South Asia. We found that the quality of the collected water is an important criterion in determining the potential uses for this water. Condensate water samples were collected from a few locations in Saudi Arabia and detailed characterizations were conducted to determine the quality of this water. We found that the quality of condensate water collected from various locations and types of air conditioners was very high with conductivities reaching as low as 18 μS/cm and turbidities of 0. 041 NTU. The quality of the collected condensate was close to that of distilled water and, with low-cost polishing treatments, such as ion exchange resins and electrochemical processes, the condensate quality could easily reach that of potable water. © 2012 Springer Science+Business Media Dordrecht.

  11. Global warming enhances sulphide stress in a key seagrass species (NW Mediterranean).

    Science.gov (United States)

    García, Rosa; Holmer, Marianne; Duarte, Carlos M; Marbà, Núria

    2013-12-01

    The build-up of sulphide concentrations in sediments, resulting from high inputs of organic matter and the mineralization through sulphate reduction, can be lethal to the benthos. Sulphate reduction is temperature dependent, thus global warming may contribute to even higher sulphide concentrations and benthos mortality. The seagrass Posidonia oceanica is very sensitive to sulphide stress. Hence, if concentrations build up with global warming, this key Mediterranean species could be seriously endangered. An 8-year monitoring of daily seawater temperature, the sulphur isotopic signatures of water (δ(34)S(water)), sediment (δ(34)SCRS ) and P. oceanica leaf tissue (δ(34)S(leaves)), along with total sulphur in leaves (TS(leaves)) and annual net population growth along the coast of the Balearic archipelago (Western Mediterranean) allowed us to determine if warming triggers P. oceanica sulphide stress and constrains seagrass survival. From the isotopic S signatures, we estimated sulphide intrusion into the leaves (F(sulphide)) and sulphur incorporation into the leaves from sedimentary sulphides (SS(leaves)). We observed lower δ(34)S(leaves), higher F(sulphide) and SS(leaves) coinciding with a 6-year period when two heat waves were recorded. Warming triggered sulphide stress as evidenced by the negative temperature dependence of δ(34)S(leaves) and the positive one of F(sulphide), TS(leaves) and SS(leaves). Lower P. oceanica net population growth rates were directly related to higher contents of TS(leaves). At equivalent annual maximum sea surface water temperature (SST(max)), deep meadows were less affected by sulphide intrusion than shallow ones. Thus, water depth acts as a protecting mechanism against sulphide intrusion. However, water depth would be insufficient to buffer seagrass sulphide stress triggered by Mediterranean seawater summer temperatures projected for the end of the 21st century even under scenarios of moderate greenhouse gas emissions, A1B

  12. Global change and water resources in the next 100 years

    Science.gov (United States)

    Larsen, M. C.; Hirsch, R. M.

    2010-03-01

    We are in the midst of a continental-scale, multi-year experiment in the United States, in which we have not defined our testable hypotheses or set the duration and scope of the experiment, which poses major water-resources challenges for the 21st century. What are we doing? We are expanding population at three times the national growth rate in our most water-scarce region, the southwestern United States, where water stress is already great and modeling predicts decreased streamflow by the middle of this century. We are expanding irrigated agriculture from the west into the east, particularly to the southeastern states, where increased competition for ground and surface water has urban, agricultural, and environmental interests at odds, and increasingly, in court. We are expanding our consumption of pharmaceutical and personal care products to historic high levels and disposing them in surface and groundwater, through sewage treatment plants and individual septic systems. These substances are now detectable at very low concentrations and we have documented significant effects on aquatic species, particularly on fish reproduction function. We don’t yet know what effects on human health may emerge, nor do we know if we need to make large investments in water treatment systems, which were not designed to remove these substances. These are a few examples of our national-scale experiment. In addition to these water resources challenges, over which we have some control, climate change models indicate that precipitation and streamflow patterns will change in coming decades, with western mid-latitude North America generally drier. We have already documented trends in more rain and less snow in western mountains. This has large implications for water supply and storage, and groundwater recharge. We have documented earlier snowmelt peak spring runoff in northeastern and northwestern States, and western montane regions. Peak runoff is now about two weeks earlier than it was

  13. Global modelling of river water quality under climate change

    Science.gov (United States)

    van Vliet, Michelle T. H.; Franssen, Wietse H. P.; Yearsley, John R.

    2017-04-01

    Climate change will pose challenges on the quality of freshwater resources for human use and ecosystems for instance by changing the dilution capacity and by affecting the rate of chemical processes in rivers. Here we assess the impacts of climate change and induced streamflow changes on a selection of water quality parameters for river basins globally. We used the Variable Infiltration Capacity (VIC) model and a newly developed global water quality module for salinity, temperature, dissolved oxygen and biochemical oxygen demand. The modelling framework was validated using observed records of streamflow, water temperature, chloride, electrical conductivity, dissolved oxygen and biochemical oxygen demand for 1981-2010. VIC and the water quality module were then forced with an ensemble of bias-corrected General Circulation Model (GCM) output for the representative concentration pathways RCP2.6 and RCP8.5 to study water quality trends and identify critical regions (hotspots) of water quality deterioration for the 21st century.

  14. Physical and virtual water transfers for regional water stress alleviation in China.

    Science.gov (United States)

    Zhao, Xu; Liu, Junguo; Liu, Qingying; Tillotson, Martin R; Guan, Dabo; Hubacek, Klaus

    2015-01-27

    Water can be redistributed through, in physical terms, water transfer projects and virtually, embodied water for the production of traded products. Here, we explore whether such water redistributions can help mitigate water stress in China. This study, for the first time to our knowledge, both compiles a full inventory for physical water transfers at a provincial level and maps virtual water flows between Chinese provinces in 2007 and 2030. Our results show that, at the national level, physical water flows because of the major water transfer projects amounted to 4.5% of national water supply, whereas virtual water flows accounted for 35% (varies between 11% and 65% at the provincial level) in 2007. Furthermore, our analysis shows that both physical and virtual water flows do not play a major role in mitigating water stress in the water-receiving regions but exacerbate water stress for the water-exporting regions of China. Future water stress in the main water-exporting provinces is likely to increase further based on our analysis of the historical trajectory of the major governing socioeconomic and technical factors and the full implementation of policy initiatives relating to water use and economic development. Improving water use efficiency is key to mitigating water stress, but the efficiency gains will be largely offset by the water demand increase caused by continued economic development. We conclude that much greater attention needs to be paid to water demand management rather than the current focus on supply-oriented management.

  15. Water stress induces overexpression of superoxide dismutases that ...

    African Journals Online (AJOL)

    Water stress is known to induce active oxygen species in plants. The accumulation of these harmful species must be prevented by plants as rapidly as possible to maintain growth and productivity. The aim of this study was to determine the effect of water stress on superoxide dismutase isozymes (SOD, EC 1.15.1.1.) in two ...

  16. Effect of progressive water deficit stress on proline accumulation and ...

    African Journals Online (AJOL)

    Water deficit stress is one of the important factors limiting chickpea production in arid and semi-arid regions of West Asia and North Africa. When water deficit stress is imposed, different molecular and biochemical responses take place. This study was carried out to investigate proline accumulation and protein profiles of ...

  17. MONITORING ON PLANT LEAF WATER POTENTIAL USING NIR SPECTROSCOPY FOR WATER STRESS MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Diding Suhandy

    2012-12-01

    Full Text Available The performance of the calibration model with temperature compensation for on-plant leaf water potential (LWP determination in tomato plants was evaluated. During a cycle of water stress, the on-plant LWP measurement was conducted. The result showed that the LWP values under water stress and recovery from water stress could be monitored well. It showed that a real time monitoring of the LWP values using NIR spectroscopy could be possible.   Keywords: water stress, real time monitoring of leaf water potential, NIR spectroscopy, plant response-based

  18. Measuring Global Water Security Towards Sustainable Development Goals

    Science.gov (United States)

    Gain, Animesh K.; Giupponi, Carlo; Wada, Yoshihide

    2016-01-01

    Water plays an important role in underpinning equitable, stable and productive societies and ecosystems. Hence, United Nations recognized ensuring water security as one (Goal 6) of the seventeen sustainable development goals (SDGs). Many international river basins are likely to experience 'low water security' over the coming decades. Water security is rooted not only in the physical availability of freshwater resources relative to water demand, but also on social and economic factors (e.g. sound water planning and management approaches, institutional capacity to provide water services, sustainable economic policies). Until recently, advanced tools and methods are available for the assessment of water scarcity. However, quantitative and integrated-physical and socio-economic-approaches for spatial analysis of water security at global level are not available yet. In this study, we present a spatial multi-criteria analysis framework to provide a global assessment of water security. The selected indicators are based on Goal 6 of SDGs. The term 'security' is conceptualized as a function of 'availability', 'accessibility to services', 'safety and quality', and 'management'. The proposed global water security index (GWSI) is calculated by aggregating indicator values on a pixel-by-pixel basis, using the ordered weighted average method, which allows for the exploration of the sensitivity of final maps to different attitudes of hypothetical policy makers. Our assessment suggests that countries of Africa, South Asia and Middle East experience very low water security. Other areas of high water scarcity, such as some parts of United States, Australia and Southern Europe, show better GWSI values, due to good performance of management, safety and quality, and accessibility. The GWSI maps show the areas of the world in which integrated strategies are needed to achieve water related targets of the SDGs particularly in the African and Asian continents.

  19. Measuring global water security towards sustainable development goals

    Science.gov (United States)

    Gain, Animesh K.; Giupponi, Carlo; Wada, Yoshihide

    2016-12-01

    Water plays an important role in underpinning equitable, stable and productive societies and ecosystems. Hence, United Nations recognized ensuring water security as one (Goal 6) of the seventeen sustainable development goals (SDGs). Many international river basins are likely to experience ‘low water security’ over the coming decades. Water security is rooted not only in the physical availability of freshwater resources relative to water demand, but also on social and economic factors (e.g. sound water planning and management approaches, institutional capacity to provide water services, sustainable economic policies). Until recently, advanced tools and methods are available for the assessment of water scarcity. However, quantitative and integrated—physical and socio-economic—approaches for spatial analysis of water security at global level are not available yet. In this study, we present a spatial multi-criteria analysis framework to provide a global assessment of water security. The selected indicators are based on Goal 6 of SDGs. The term ‘security’ is conceptualized as a function of ‘availability’, ‘accessibility to services’, ‘safety and quality’, and ‘management’. The proposed global water security index (GWSI) is calculated by aggregating indicator values on a pixel-by-pixel basis, using the ordered weighted average method, which allows for the exploration of the sensitivity of final maps to different attitudes of hypothetical policy makers. Our assessment suggests that countries of Africa, South Asia and Middle East experience very low water security. Other areas of high water scarcity, such as some parts of United States, Australia and Southern Europe, show better GWSI values, due to good performance of management, safety and quality, and accessibility. The GWSI maps show the areas of the world in which integrated strategies are needed to achieve water related targets of the SDGs particularly in the African and Asian continents.

  20. How important are peatlands globally in providing drinking water resources?

    Science.gov (United States)

    Xu, Jiren; Morris, Paul; Holden, Joseph

    2017-04-01

    The potential role of peatlands as water stores and sources of downstream water resources for human use is often cited in publications setting the context for the importance of peatlands, but is rarely backed up with substantive evidence. We sought to determine the global role of peatlands in water resource provision. We developed the Peat Population Index (PPI) that combines the coverage of peat and the local population density to show focused (hotspot) areas where there is a combination of both large areas of peat and large populations who would potentially use water sourced from those peatlands. We also developed a method for estimating the proportion of river water that interacted with contributing peatlands before draining into rivers and reservoirs used as a drinking water resource. The Peat Reservoir Index (PRI) estimates the contribution of peatlands to domestic water use to be 1.64 km3 per year which is 0.35 % of the global total. The results suggest that although peatlands are widespread, the spatial distribution of the high PPI and PRI river basins is concentrated in European middle latitudes particularly around major conurbations in The Netherlands, northern England, Scotland (Glasgow) and Ireland (Dublin), although there were also some important systems in Florida, the Niger Delta and Malaysia. More detailed research into water resource provision in high PPI areas showed that they were not always also high PRI areas as often water resources were delivered to urban centres from non-peat areas, despite a large area of peat within the catchment. However, particularly in the UK and Ireland, there are some high PRI systems where peatlands directly supply water to nearby urban centres. Thus both indices are useful and can be used at a global level while more local refinement enables enhanced use which supports global and local peatland protection measures. We now intend to study the impacts of peatland degradation and climate change on water resource

  1. Impact of emerging clean vehicle system on water stress

    International Nuclear Information System (INIS)

    Cai, Hua; Hu, Xiaojun; Xu, Ming

    2013-01-01

    Graphical abstract: Display Omitted - Highlights: • Clean vehicles may increase US water consumption up to 2810 billion gallons/year. • Large-scale clean vehicle adoption could lead to severe regional water stress. • Fuel choice for clean vehicle is crucial in minimizing regional water stress. • Regional optimization illustrated the importance of regional consideration. - Abstract: While clean vehicles (i.e., vehicles powered by alternative fuels other than fossil fuels) offer great potential to reduce greenhouse gas emissions from gasoline-based vehicles, the associated impact on water resources has not yet been fully assessed. This research provides a systematic evaluation of the impact of a fully implemented clean vehicle system on national and state-level water demand and water stress. On the national level, based on existing policies, transitioning the current gasoline-based transportation into one with clean vehicles will increase national annual water consumption by 1950–2810 billion gallons of water, depending on the market penetration of electric vehicles. On the state level, variances of water efficiency in producing different fuels are significant. The fuel choice for clean vehicle development is especially crucial for minimizing water stress increase in states with already high water stress, high travel demands, and significant variations in water efficiency in producing different alternative fuels. Current development of clean vehicle infrastructure, however, has not reflected these state-level variations. This study takes an optimization approach to further evaluate impacts on state-level water stress from a fully implemented clean vehicle system and identified potential roles (fuel producer or consumer) states may play in real world clean vehicle development scenario. With an objective of minimizing overall water stress impact, our optimization model aims to provide an analytical framework to better assess impacts on state-level water

  2. Grafting improves cucumber water stress tolerance in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Abdulaziz R. Al-Harbi

    2018-02-01

    Full Text Available Water scarcity is a major limiting factor for crop productivity in arid and semi-arid areas. Grafting elite commercial cultivars onto selected vigorous rootstocks is considered as a useful strategy to alleviate the impact of environmental stresses. This study aims to investigate the feasibility of using grafting to improve fruit yield and quality of cucumber under water stress conditions. Alosama F1 cucumber cultivar (Cucumis sativus L. was grafted onto Affyne (Cucumis sativus L. and Shintoza A90 (Cucurbitamaxima × C. moschata rootstocks. Non-grafted plants were used as control. All genotypes were grown under three surface drip irrigation regimes: 50%, 75% and 100% of the crop evapotranspiration (ETc, which represent high-water stress, moderate-water stress and non-water stress conditions, respectively. Yield and fruit quality traits were analyzed and assessed. In comparison to the non-grafted plants, the best grafting treatment under water stress was Alosama F1 grafted onto Shintoza A90 rootstock. It had an overall improved yield and fruit quality under water stress owing to an increase in the total fruit yield by 27%, from 4.815 kg plant−1 in non-grafted treatment to 6.149 kg plant−1 in grafted treatment under moderate -water stress, total soluble solid contents (13%, titratable acidity (39% and vitamin C (33%. The soil water contents were low in soil surface and increase gradually with soil depth, while salt distribution showed an adverse trend. The positive effects of grafting on plant growth, productivity, and water use efficiency support this strategy as an useful tool for improving water stress tolerance in greenhouse grown cucumber in Saudi Arabia.

  3. Grafting improves cucumber water stress tolerance in Saudi Arabia.

    Science.gov (United States)

    Al-Harbi, Abdulaziz R; Al-Omran, Abdulrasoul M; Alharbi, Khadiga

    2018-02-01

    Water scarcity is a major limiting factor for crop productivity in arid and semi-arid areas. Grafting elite commercial cultivars onto selected vigorous rootstocks is considered as a useful strategy to alleviate the impact of environmental stresses. This study aims to investigate the feasibility of using grafting to improve fruit yield and quality of cucumber under water stress conditions. Alosama F 1 cucumber cultivar ( Cucumis sativus L.) was grafted onto Affyne ( Cucumis sativus L.) and Shintoza A90 ( Cucurbitamaxima × C. moschata ) rootstocks. Non-grafted plants were used as control. All genotypes were grown under three surface drip irrigation regimes: 50%, 75% and 100% of the crop evapotranspiration (ETc), which represent high-water stress, moderate-water stress and non-water stress conditions, respectively. Yield and fruit quality traits were analyzed and assessed. In comparison to the non-grafted plants, the best grafting treatment under water stress was Alosama F 1 grafted onto Shintoza A90 rootstock. It had an overall improved yield and fruit quality under water stress owing to an increase in the total fruit yield by 27%, from 4.815 kg plant -1 in non-grafted treatment to 6.149 kg plant -1 in grafted treatment under moderate -water stress, total soluble solid contents (13%), titratable acidity (39%) and vitamin C (33%). The soil water contents were low in soil surface and increase gradually with soil depth, while salt distribution showed an adverse trend. The positive effects of grafting on plant growth, productivity, and water use efficiency support this strategy as an useful tool for improving water stress tolerance in greenhouse grown cucumber in Saudi Arabia.

  4. Impact of climate forcing uncertainty and human water use on global and continental water balance components

    Directory of Open Access Journals (Sweden)

    H. Müller Schmied

    2016-10-01

    Full Text Available The assessment of water balance components using global hydrological models is subject to climate forcing uncertainty as well as to an increasing intensity of human water use within the 20th century. The uncertainty of five state-of-the-art climate forcings and the resulting range of cell runoff that is simulated by the global hydrological model WaterGAP is presented. On the global land surface, about 62 % of precipitation evapotranspires, whereas 38 % discharges into oceans and inland sinks. During 1971–2000, evapotranspiration due to human water use amounted to almost 1 % of precipitation, while this anthropogenic water flow increased by a factor of approximately 5 between 1901 and 2010. Deviation of estimated global discharge from the ensemble mean due to climate forcing uncertainty is approximately 4 %. Precipitation uncertainty is the most important reason for the uncertainty of discharge and evapotranspiration, followed by shortwave downward radiation. At continental levels, deviations of water balance components due to uncertain climate forcing are higher, with the highest discharge deviations occurring for river discharge in Africa (−6 to 11 % from the ensemble mean. Uncertain climate forcings also affect the estimation of irrigation water use and thus the estimated human impact of river discharge. The uncertainty range of global irrigation water consumption amounts to approximately 50 % of the global sum of water consumption in the other water use sector.

  5. Global models underestimate large decadal declining and rising water storage trends relative to GRACE satellite data

    Science.gov (United States)

    Scanlon, Bridget R.; Zhang, Zizhan; Save, Himanshu; Sun, Alexander Y.; van Beek, Ludovicus P. H.; Wiese, David N.; Reedy, Robert C.; Longuevergne, Laurent; Döll, Petra; Bierkens, Marc F. P.

    2018-01-01

    Assessing reliability of global models is critical because of increasing reliance on these models to address past and projected future climate and human stresses on global water resources. Here, we evaluate model reliability based on a comprehensive comparison of decadal trends (2002–2014) in land water storage from seven global models (WGHM, PCR-GLOBWB, GLDAS NOAH, MOSAIC, VIC, CLM, and CLSM) to trends from three Gravity Recovery and Climate Experiment (GRACE) satellite solutions in 186 river basins (∼60% of global land area). Medians of modeled basin water storage trends greatly underestimate GRACE-derived large decreasing (≤−0.5 km3/y) and increasing (≥0.5 km3/y) trends. Decreasing trends from GRACE are mostly related to human use (irrigation) and climate variations, whereas increasing trends reflect climate variations. For example, in the Amazon, GRACE estimates a large increasing trend of ∼43 km3/y, whereas most models estimate decreasing trends (−71 to 11 km3/y). Land water storage trends, summed over all basins, are positive for GRACE (∼71–82 km3/y) but negative for models (−450 to −12 km3/y), contributing opposing trends to global mean sea level change. Impacts of climate forcing on decadal land water storage trends exceed those of modeled human intervention by about a factor of 2. The model-GRACE comparison highlights potential areas of future model development, particularly simulated water storage. The inability of models to capture large decadal water storage trends based on GRACE indicates that model projections of climate and human-induced water storage changes may be underestimated. PMID:29358394

  6. Separating decadal global water cycle variability from sea level rise.

    Science.gov (United States)

    Hamlington, B D; Reager, J T; Lo, M-H; Karnauskas, K B; Leben, R R

    2017-04-20

    Under a warming climate, amplification of the water cycle and changes in precipitation patterns over land are expected to occur, subsequently impacting the terrestrial water balance. On global scales, such changes in terrestrial water storage (TWS) will be reflected in the water contained in the ocean and can manifest as global sea level variations. Naturally occurring climate-driven TWS variability can temporarily obscure the long-term trend in sea level rise, in addition to modulating the impacts of sea level rise through natural periodic undulation in regional and global sea level. The internal variability of the global water cycle, therefore, confounds both the detection and attribution of sea level rise. Here, we use a suite of observations to quantify and map the contribution of TWS variability to sea level variability on decadal timescales. In particular, we find that decadal sea level variability centered in the Pacific Ocean is closely tied to low frequency variability of TWS in key areas across the globe. The unambiguous identification and clean separation of this component of variability is the missing step in uncovering the anthropogenic trend in sea level and understanding the potential for low-frequency modulation of future TWS impacts including flooding and drought.

  7. Ecological network analysis on global virtual water trade.

    Science.gov (United States)

    Yang, Zhifeng; Mao, Xufeng; Zhao, Xu; Chen, Bin

    2012-02-07

    Global water interdependencies are likely to increase with growing virtual water trade. To address the issues of the indirect effects of water trade through the global economic circulation, we use ecological network analysis (ENA) to shed insight into the complicated system interactions. A global model of virtual water flow among agriculture and livestock production trade in 1995-1999 is also built as the basis for network analysis. Control analysis is used to identify the quantitative control or dependency relations. The utility analysis provides more indicators for describing the mutual relationship between two regions/countries by imitating the interactions in the ecosystem and distinguishes the beneficiary and the contributor of virtual water trade system. Results show control and utility relations can well depict the mutual relation in trade system, and direct observable relations differ from integral ones with indirect interactions considered. This paper offers a new way to depict the interrelations between trade components and can serve as a meaningful start as we continue to use ENA in providing more valuable implications for freshwater study on a global scale.

  8. Regulation of water resources for sustaining global future socioeconomic development

    Science.gov (United States)

    Chen, J.; SHI, H.; Sivakumar, B.

    2016-12-01

    With population projections indicating continued growth during this century, socio-economic problems (e.g., water, food, and energy shortages) will be most likely to occur, especially if proper planning, development, and management strategies are not adopted. In the present study, firstly, we explore the vital role of dams in promoting economic growth through analyzing the relationship between dams and Gross Domestic Product (GDP) at both global and national scales. Secondly, we analyze the current situation of global water scarcity based on the data representing water resources availability, dam development, and the level of economic development. Third, with comprehensive consideration of population growth as the major driving force, water resources availability as the basic supporting factor, and topography as the important constraint, this study addresses the question of dam development in the future and predicts the locations of future dams around the world.

  9. Analysis of key thresholds leading to upstream dependencies in global transboundary water bodies

    Science.gov (United States)

    Munia, Hafsa Ahmed; Guillaume, Joseph; Kummu, Matti; Mirumachi, Naho; Wada, Yoshihide

    2017-04-01

    Transboundary water bodies supply 60% of global fresh water flow and are home to about 1/3 of the world's population; creating hydrological, social and economic interdependencies between countries. Trade-offs between water users are delimited by certain thresholds, that, when crossed, result in changes in system behavior, often related to undesirable impacts. A wide variety of thresholds are potentially related to water availability and scarcity. Scarcity can occur because of the country's own water use, and that is potentially intensified by upstream water use. In general, increased water scarcity escalates the reliance on shared water resources, which increases interdependencies between riparian states. In this paper the upstream dependencies of global transboundary river basins are examined at the scale of sub-basin areas. We aim to assess how upstream water withdrawals cause changes in the scarcity categories, such that crossing thresholds is interpreted in terms of downstream dependency on upstream water availability. The thresholds are defined for different types of water availability on which a sub-basin relies: - reliable local runoff (available even in a dry year), - less reliable local water (available in the wet year), - reliable dry year inflows from possible upstream area, and - less reliable wet year inflows from upstream. Possible upstream withdrawals reduce available water downstream, influencing the latter two water availabilities. Upstream dependencies have then been categorized by comparing a sub-basin's scarcity category across different water availability types. When population (or water consumption) grows, the sub-basin satisfies its needs using less reliable water. Thus, the factors affecting the type of water availability being used are different not only for each type of dependency category, but also possibly for every sub- basin. Our results show that, in the case of stress (impacts from high use of water), in 104 (12%) sub- basins out of

  10. Differential response to water deficit stress in alfalfa ( Medicago ...

    African Journals Online (AJOL)

    The present study was fixed as objective to compare the response to water deficit (33% of field capacity, FC) stress of eight cultivars of Medicago sativa, originating from the Mediterranean basin. Comparison was performed on some key parameters such as growth, relative water content, leaf water potential, MDA tissue ...

  11. A Seamless Framework for Global Water Cycle Monitoring and Prediction

    Science.gov (United States)

    Sheffield, J.; Wood, E. F.; Chaney, N.; Fisher, C. K.; Caylor, K. K.

    2013-12-01

    The Global Earth Observation System of Systems (GEOSS) Water Strategy ('From Observations to Decisions') recognizes that 'water is essential for ensuring food and energy security, for facilitating poverty reduction and health security, and for the maintenance of ecosystems and biodiversity', and that water cycle data and observations are critical for improved water management and water security - especially in less developed regions. The GEOSS Water Strategy has articulated a number of goals for improved water management, including flood and drought preparedness, that include: (i) facilitating the use of Earth Observations for water cycle observations; (ii) facilitating the acquisition, processing, and distribution of data products needed for effective management; (iii) providing expertise, information systems, and datasets to the global, regional, and national water communities. There are several challenges that must be met to advance our capability to provide near real-time water cycle monitoring, early warning of hydrological hazards (floods and droughts) and risk assessment under climate change, regionally and globally. Current approaches to monitoring and predicting hydrological hazards are limited in many parts of the world, and especially in developing countries where national capacity is limited and monitoring networks are inadequate. This presentation describes the development of a seamless monitoring and prediction framework at all time scales that allows for consistent assessment of water variability from historic to current conditions, and from seasonal and decadal predictions to climate change projections. At the center of the framework is an experimental, global water cycle monitoring and seasonal forecast system that has evolved out of regional and continental systems for the US and Africa. The system is based on land surface hydrological modeling that is driven by satellite remote sensing precipitation to predict current hydrological conditions

  12. Determining water reservoir characteristics with global elevation data

    NARCIS (Netherlands)

    van Bemmelen, C. W T; Mann, M.; de Ridder, M.P.; Rutten, M.M.; van de Giesen, N.C.

    2016-01-01

    Quantification of human impact on water, sediment, and nutrient fluxes at the global scale demands characterization of reservoirs with an accuracy that is presently unavailable. This letter presents a new method, based on virtual dam placement, to make accurate estimations of area-volume

  13. Modeling of the Global Water Cycle - Analytical Models

    Science.gov (United States)

    Yongqiang Liu; Roni Avissar

    2005-01-01

    Both numerical and analytical models of coupled atmosphere and its underlying ground components (land, ocean, ice) are useful tools for modeling the global and regional water cycle. Unlike complex three-dimensional climate models, which need very large computing resources and involve a large number of complicated interactions often difficult to interpret, analytical...

  14. Modeling global distribution of agricultural insecticides in surface waters.

    Science.gov (United States)

    Ippolito, Alessio; Kattwinkel, Mira; Rasmussen, Jes J; Schäfer, Ralf B; Fornaroli, Riccardo; Liess, Matthias

    2015-03-01

    Agricultural insecticides constitute a major driver of animal biodiversity loss in freshwater ecosystems. However, the global extent of their effects and the spatial extent of exposure remain largely unknown. We applied a spatially explicit model to estimate the potential for agricultural insecticide runoff into streams. Water bodies within 40% of the global land surface were at risk of insecticide runoff. We separated the influence of natural factors and variables under human control determining insecticide runoff. In the northern hemisphere, insecticide runoff presented a latitudinal gradient mainly driven by insecticide application rate; in the southern hemisphere, a combination of daily rainfall intensity, terrain slope, agricultural intensity and insecticide application rate determined the process. The model predicted the upper limit of observed insecticide exposure measured in water bodies (n = 82) in five different countries reasonably well. The study provides a global map of hotspots for insecticide contamination guiding future freshwater management and conservation efforts. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Effect of water deficit stress on proline contents, soluble sugars ...

    African Journals Online (AJOL)

    Effect of water deficit stress on proline contents, soluble sugars, chlorophyll and grain yield of sunflower ... Journal Home > Vol 11, No 1 (2012) > ... The objective of the present work was to determine the mechanisms of tolerance of four ...

  16. Effects of temperature and water stresses on germination of some ...

    African Journals Online (AJOL)

    Therefore, we opted for the Chetoui variety that better meets the conditions of stresses induced by low temperatures and water deficit. This best performing variety must have, throughout their development cycle, been tolerant to environmental stresses; which allows us to obtain early tools for discriminative selection between ...

  17. Water stress induces overexpression of superoxide dismutases that ...

    African Journals Online (AJOL)

    SERVER

    2007-09-05

    Sep 5, 2007 ... Water stress is known to induce active oxygen species in plants. ... photosystem II photochemistry and whole plant growth against oxidative stress in these plants. ..... CO2. Plant Physiol. 110: 393-402. Sen Gupta A, Heinen JL, ...

  18. Water stress effects on spatially referenced cotton crop canopy properties

    Science.gov (United States)

    rop canopy temperature is known to be affected by water stress. Canopy reflectance can also be impacted as leaf orientation and color respond to the stress. As sensor systems are investigated for real-time management of irrigation and nitrogen, it is essential to understand how the data from the sen...

  19. Transient water stress in a vegetation canopy - Simulations and measurements

    Science.gov (United States)

    Carlson, Toby N.; Belles, James E.; Gillies, Robert R.

    1991-01-01

    Consideration is given to observational and modeling evidence of transient water stress, the effects of the transpiration plateau on the canopy radiometric temperature, and the factors responsible for the onset of the transpiration plateau, such as soil moisture. Attention is also given to the point at which the transient stress can be detected by remote measurement of surface temperature.

  20. Multi-modal sensor system for plant water stress assessment

    Science.gov (United States)

    Plant stress critically affects plant growth and causes significant loss of productivity and quality. When the plant is under water stress, it impedes photosynthesis and transpiration, resulting in changes in leaf color and temperature. Leaf discoloration in photosynthesis can be assessed by measu...

  1. Cytokinin Activity in Water-stressed Shoots 1

    Science.gov (United States)

    Itai, Chanan; Vaadia, Yoash

    1971-01-01

    Water stress applied to the plant shoot through enhanced evaporative demands reduced cytokinin activity in extracts of xylem exudate and leaves. This reduction resembled the changes in cytokinin activity caused by water stress applied to the root. Cytokinin activity in detached wilting leaves decreased rapidly. Recovery took place after several hours in a humid chamber. Experiments with 14C-kinetin indicated that the mechanism of the inactivation and its reversal involve a chemical transformation of the cytokinin molecule. PMID:16657585

  2. Global seasonal strain and stress models derived from GRACE loading, and their impact on seismicity

    Science.gov (United States)

    Chanard, K.; Fleitout, L.; Calais, E.; Craig, T. J.; Rebischung, P.; Avouac, J. P.

    2017-12-01

    Loading by continental water, atmosphere and oceans deforms the Earth at various spatio-temporal scales, inducing crustal and mantelic stress perturbations that may play a role in earthquake triggering.Deformation of the Earth by this surface loading is observed in GNSS position time series. While various models predict well vertical observations, explaining horizontal displacements remains challenging. We model the elastic deformation induced by loading derived from GRACE for coefficients 2 and higher. We estimate the degree-1 deformation field by comparison between predictions of our model and IGS-repro2 solutions at a globally distributed network of 700 GNSS sites, separating the horizontal and vertical components to avoid biases between components. The misfit between model and data is reduced compared to previous studies, particularly on the horizontal component. The associated geocenter motion time series are consistent with results derived from other datasets. We also discuss the impact on our results of systematic errors in GNSS geodetic products, in particular of the draconitic error.We then compute stress tensors time series induced by GRACE loads and discuss the potential link between large scale seasonal mass redistributions and seismicity. Within the crust, we estimate hydrologically induced stresses in the intraplate New Madrid Seismic Zone, where secular stressing rates are unmeasurably low. We show that a significant variation in the rate of micro-earthquakes at annual and multi-annual timescales coincides with stresses induced by hydrological loading in the upper Mississippi embayment, with no significant phase-lag, directly modulating regional seismicity. We also investigate pressure variations in the mantle transition zone and discuss potential correlations between the statistically significant observed seasonality of deep-focus earthquakes, most likely due to mineralogical transformations, and surface hydrological loading.

  3. INTRODUCTION: Anticipated changes in the global atmospheric water cycle

    Science.gov (United States)

    Allan, Richard P.; Liepert, Beate G.

    2010-06-01

    The atmospheric branch of the water cycle, although containing just a tiny fraction of the Earth's total water reserves, presents a crucial interface between the physical climate (such as large-scale rainfall patterns) and the ecosystems upon which human societies ultimately depend. Because of the central importance of water in the Earth system, the question of how the water cycle is changing, and how it may alter in future as a result of anthropogenic changes, present one of the greatest challenges of this century. The recent Intergovernmental Panel on Climate Change report on Climate Change and Water (Bates et al 2008) highlighted the increasingly strong evidence of change in the global water cycle and associated environmental consequences. It is of critical importance to climate prediction and adaptation strategies that key processes in the atmospheric water cycle are precisely understood and determined, from evaporation at the surface of the ocean, transport by the atmosphere, condensation as cloud and eventual precipitation, and run-off through rivers following interaction with the land surface, sub-surface, ice, snow and vegetation. The purpose of this special focus issue of Environmental Research Letters on anticipated changes in the global atmospheric water cycle is to consolidate the recent substantial advances in understanding past, present and future changes in the global water cycle through evidence built upon theoretical understanding, backed up by observations and borne out by climate model simulations. Thermodynamic rises in water vapour provide a central constraint, as discussed in a guest editorial by Bengtsson (2010). Theoretical implications of the Clausius-Clapeyron equation are presented by O'Gorman and Muller (2010) and with reference to a simple model (Sherwood 2010) while observed humidity changes confirm these anticipated responses at the land and ocean surface (Willett et al 2008). Rises in low-level moisture are thought to fuel an

  4. Navigating Troubled Waters. An analysis of how urban water regimes in the global South reproduce inequality

    OpenAIRE

    Nastar, Maryam

    2014-01-01

    This research is an attempt to conceptualize the underlying forces behind persistent and ubiquitous problems of inequality in access to water in cities of the global south. Inequality in water access is hypothesized to result from urban water regimes that tend to prioritize the right to water access or to provide preferential terms of access for some groups in society, while marginalizing others. By employing a critical realist approach, different theories in relation to inequality are app...

  5. Global Occurrence and Emission of Rotaviruses to Surface Waters

    Directory of Open Access Journals (Sweden)

    Nicholas M. Kiulia

    2015-05-01

    Full Text Available Group A rotaviruses (RV are the major cause of acute gastroenteritis in infants and young children globally. Waterborne transmission of RV and the presence of RV in water sources are of major public health importance. In this paper, we present the Global Waterborne Pathogen model for RV (GloWPa-Rota model to estimate the global distribution of RV emissions to surface water. To our knowledge, this is the first model to do so. We review the literature to estimate three RV specific variables for the model: incidence, excretion rate and removal during wastewater treatment. We estimate total global RV emissions to be 2 × 1018 viral particles/grid/year, of which 87% is produced by the urban population. Hotspot regions with high RV emissions are urban areas in densely populated parts of the world, such as Bangladesh and Nigeria, while low emissions are found in rural areas in North Russia and the Australian desert. Even for industrialized regions with high population density and without tertiary treatment, such as the UK, substantial emissions are estimated. Modeling exercises like the one presented in this paper provide unique opportunities to further study these emissions to surface water, their sources and scenarios for improved management.

  6. Local and global perspectives on the virtual water trade

    Directory of Open Access Journals (Sweden)

    S. Tamea

    2013-03-01

    Full Text Available Recent studies on fluxes of virtual water are showing how the global food and goods trade interconnects the water resources of different and distant countries, conditioning the local water balances. This paper presents and discusses the assessment of virtual water fluxes between a single country and its network of trading partners, delineating a country's virtual water budget in space and time (years 1986–2010. The fluxes between the country under study and its importing/exporting partners are visualized with a geographical representation shaping the trade network as a virtual river/delta. Time variations of exchanged fluxes are quantified to show possible trends in the virtual water balance, while characterizing the time evolution of the trade network and its composition in terms of product categories (plant-based, animal-based, luxury food, and non-edible. The average distance traveled by virtual water to arrive to the place of consumption is also introduced as a new measure for the analysis of globalization of the virtual water trade. Using Italy as an example, we find that food trade has a steadily growing importance compared to domestic production, with a major component represented by plant-based products, and luxury products taking an increasingly larger share (26% in 2010. In 2010 Italy had an average net import of 55 km3 of virtual water (38 km3 in 1986, a value which poses the country among the top net importers in the world. On average each cubic meter of virtual water travels nearly 4000 km before entering Italy, while export goes to relatively closer countries (average distance: 2600 km, with increasing trends in time which are almost unique among the world countries. Analyses proposed for Italy are replicated for 10 other world countries, triggering similar investigations on different socio-economic actualities.

  7. Local and global perspectives on the virtual water trade

    Science.gov (United States)

    Tamea, S.; Allamano, P.; Carr, J. A.; Claps, P.; Laio, F.; Ridolfi, L.

    2013-03-01

    Recent studies on fluxes of virtual water are showing how the global food and goods trade interconnects the water resources of different and distant countries, conditioning the local water balances. This paper presents and discusses the assessment of virtual water fluxes between a single country and its network of trading partners, delineating a country's virtual water budget in space and time (years 1986-2010). The fluxes between the country under study and its importing/exporting partners are visualized with a geographical representation shaping the trade network as a virtual river/delta. Time variations of exchanged fluxes are quantified to show possible trends in the virtual water balance, while characterizing the time evolution of the trade network and its composition in terms of product categories (plant-based, animal-based, luxury food, and non-edible). The average distance traveled by virtual water to arrive to the place of consumption is also introduced as a new measure for the analysis of globalization of the virtual water trade. Using Italy as an example, we find that food trade has a steadily growing importance compared to domestic production, with a major component represented by plant-based products, and luxury products taking an increasingly larger share (26% in 2010). In 2010 Italy had an average net import of 55 km3 of virtual water (38 km3 in 1986), a value which poses the country among the top net importers in the world. On average each cubic meter of virtual water travels nearly 4000 km before entering Italy, while export goes to relatively closer countries (average distance: 2600 km), with increasing trends in time which are almost unique among the world countries. Analyses proposed for Italy are replicated for 10 other world countries, triggering similar investigations on different socio-economic actualities.

  8. Spacebased Observation of Water Balance Over Global Oceans

    Science.gov (United States)

    Liu, W.; Xie, X.

    2008-12-01

    We demonstrated that ocean surface fresh water flux less the water discharge into the ocean from river and ice melt balances the mass loss in the ocean both in magnitude and in the phase of annual variation. The surface water flux was computed from the divergence of the water transport integrated over the depth of the atmosphere. The atmospheric water transport is estimated from the precipitable water measured by Special Sensor Microwave Imager, the surface wind vector by QuikSCAT, and the NOAA cloud drift wind through a statistical model. The transport has been extensively validated using global radiosonde and data and operational numerical weather prediction results. Its divergence has been shown to agree with the difference between evaporation estimated from the Advanced Microwave Scanning Radiometer data and the precipitation measured by Tropical Rain Measuring Mission over the global tropical and subtropical oceans both in magnitude and geographical distribution for temporal scales ranging from intraseasonal to interannual. The water loss rate in the ocean is estimated by two methods, one is from Gravity Recovery and Climate Experiment and the other is by subtracting the climatological steric change from the sea level change measured by radar altimeter on Jason. Only climatological river discharge and ice melt from in situ measurements are available and the lack of temporal variation may contribute to discrepancies in the balance. We have successfully used the spacebased surface fluxes to estimate to climatological mean heat transport in the Atlantic ocean and is attempting to estimate the meridional fresh water (or salt) transport from the surface flux. The approximate closure of the water balance gives a powerful indirect validation of the spacebased products.

  9. Spectral reflectance relationships to leaf water stress

    Science.gov (United States)

    Ripple, William J.

    1986-01-01

    Spectral reflectance data were collected from detached snapbean leaves in the laboratory with a multiband radiometer. Four experiments were designed to study the spectral response resulting from changes in leaf cover, relative water content of leaves, and leaf water potential. Spectral regions included in the analysis were red (630-690 nm), NIR (760-900 nm), and mid-IR (2.08-2.35 microns). The red and mid-IR bands showed sensitivity to changes in both leaf cover and relative water content of leaves. The NIR was only highly sensitive to changes in leaf cover. Results provided evidence that mid-IR reflectance was governed primarily by leaf moisture content, although soil reflectance was an important factor when leaf cover was less than 100 percent. High correlations between leaf water potentials and reflectance were attributed to covariances with relative water content of leaves and leaf cover.

  10. A global water scarcity assessment under Shared Socio-economic Pathways – Part 1: Water use

    Directory of Open Access Journals (Sweden)

    N. Hanasaki

    2013-07-01

    Full Text Available A novel global water scarcity assessment for the 21st century is presented in a two-part paper. In this first paper, water use scenarios are presented for the latest global hydrological models. The scenarios are compatible with the socio-economic scenarios of the Shared Socio-economic Pathways (SSPs, which are a part of the latest set of scenarios on global change developed by the integrated assessment, the IAV (climate change impact, adaptation, and vulnerability assessment, and the climate modeling community. The SSPs depict five global situations based on substantially different socio-economic conditions during the 21st century. Water use scenarios were developed to reflect not only quantitative socio-economic factors, such as population and electricity production, but also key qualitative concepts such as the degree of technological change and overall environmental consciousness. Each scenario consists of five factors: irrigated area, crop intensity, irrigation efficiency, and withdrawal-based potential industrial and municipal water demands. The first three factors are used to estimate the potential irrigation water demand. All factors were developed using simple models based on a literature review and analysis of historical records. The factors are grid-based at a spatial resolution of 0.5° × 0.5° and cover the whole 21st century in five-year intervals. Each factor shows wide variation among the different global situations depicted: the irrigated area in 2085 varies between 2.7 × 106 and 4.5 × 106 km2, withdrawal-based potential industrial water demand between 246 and 1714 km3 yr−1, and municipal water between 573 and 1280 km3 yr−1. The water use scenarios can be used for global water scarcity assessments that identify the regions vulnerable to water scarcity and analyze the timing and magnitude of scarcity conditions.

  11. Drought genetics have varying influence on corn water stress under differing water availability

    Science.gov (United States)

    Irrigated corn (Zea mays L.) in the Great Plains will be increasingly grown under limited irrigation management and greater water stress. Hybrids with drought genetics may decrease the impacts of water stress on yield. The objective of this experiment was to evaluate the effect of drought genetics o...

  12. Global water risks and national security: Building resilience (Invited)

    Science.gov (United States)

    Pulwarty, R. S.

    2013-12-01

    The UN defines water security as the capacity of a population to safeguard sustainable access to adequate quantities of acceptable quality water for sustaining livelihoods, human well-being, and socio-economic development, for ensuring protection against water-borne pollution and water-related disasters, and for preserving ecosystems in a climate of peace and political stability. This definition highlights complex and interconnected challenges and underscores the centrality of water for environmental services and human aactivities. Global risks are expressed at the national level. The 2010 Quadrennial Defense Review and the 2010 National Security Strategy identify climate change as likely to trigger outcomes that will threaten U.S. security including how freshwater resources can become a security issue. Impacts will be felt on the National Security interest through water, food and energy security, and critical infrastructure. This recognition focuses the need to consider the rates of change in climate extremes, in the context of more traditional political, economic, and social indicators that inform security analyses. There is a long-standing academic debate over the extent to which resource constraints and environmental challenges lead to inter-state conflict. It is generally recognized that water resources as a security issue to date exists mainly at the substate level and has not led to physical conflict between nation states. In conflict and disaster zones, threats to water security increase through inequitable and difficult access to water supply and related services, which may aggravate existing social fragility, tensions, violence, and conflict. This paper will (1) Outline the dimensions of water security and its links to national security (2) Analyze water footprints and management risks for key basins in the US and around the world, (3) map the link between global water security and national concerns, drawing lessons from the drought of 2012 and elsewhere

  13. Improved but unsustainable: accounting for sachet water in post-2015 goals for global safe water.

    Science.gov (United States)

    Stoler, Justin

    2012-12-01

    The advent and rapid spread of sachet drinking water in West Africa presents a new challenge for providing sustainable access to global safe water. Sachet water has expanded drinking water access and is often of sufficient quality to serve as an improved water source for Millennium Development Goals (MDG) monitoring purposes, yet sachets are an unsustainable water delivery vehicle due to their overwhelming plastic waste burden. Monitoring of primary drinking water sources in West Africa generally ignores sachet water, despite its growing ubiquity. Sub-Saharan Africa as a region is unlikely to meet the MDG Target for drinking water provision, and post-2015 monitoring activities may depend upon rapid adaptability to local drinking water trends. © 2012 Blackwell Publishing Ltd.

  14. Pure culture response of ectomycorrhizal fungi to imposed water stress

    Science.gov (United States)

    Mark D. Coleman; Caroline S. Bledsoe; William Lopushinsky

    1989-01-01

    The ability of ectomycorrhizal fungal isolates to tolerate imposed water stress in pure culture was examined in 55 isolates of 18 species. Water potential treatments, adjusted with polyethylene glycol, were applied to Petri dish units. These units allowed colony diameter measurements of fungi grown on liquid media. Delayed growth initiation and inhibition of growth...

  15. Growth and physiological responses to water and nutrient stress in ...

    African Journals Online (AJOL)

    Administrator

    2011-09-07

    Sep 7, 2011 ... water and nutrient stress made significant effects on nitrogen and phosphorus concentration, but no .... Measurements of relative water content (RWC), leaf relative ... C1 is the electrical conductivity value of samples at the first .... biomass, root, stem and leaf mass) were significant. ..... Plant, Cell and Environ.

  16. Electrodermal Activity Is Sensitive to Cognitive Stress under Water.

    Science.gov (United States)

    Posada-Quintero, Hugo F; Florian, John P; Orjuela-Cañón, Alvaro D; Chon, Ki H

    2017-01-01

    When divers are at depth in water, the high pressure and low temperature alone can cause severe stress, challenging the human physiological control systems. The addition of cognitive stress, for example during a military mission, exacerbates the challenge. In these conditions, humans are more susceptible to autonomic imbalance. Reliable tools for the assessment of the autonomic nervous system (ANS) could be used as indicators of the relative degree of stress a diver is experiencing, which could reveal heightened risk during a mission. Electrodermal activity (EDA), a measure of the changes in conductance at the skin surface due to sweat production, is considered a promising alternative for the non-invasive assessment of sympathetic control of the ANS. EDA is sensitive to stress of many kinds. Therefore, as a first step, we tested the sensitivity of EDA, in the time and frequency domains, specifically to cognitive stress during water immersion of the subject (albeit with their measurement finger dry for safety). The data from 14 volunteer subjects were used from the experiment. After a 4-min adjustment and baseline period after being immersed in water, subjects underwent the Stroop task, which is known to induce cognitive stress. The time-domain indices of EDA, skin conductance level (SCL) and non-specific skin conductance responses (NS.SCRs), did not change during cognitive stress, compared to baseline measurements. Frequency-domain indices of EDA, EDASymp (based on power spectral analysis) and TVSymp (based on time-frequency analysis), did significantly change during cognitive stress. This leads to the conclusion that EDA, assessed by spectral analysis, is sensitive to cognitive stress in water-immersed subjects, and can potentially be used to detect cognitive stress in divers.

  17. Electrodermal Activity Is Sensitive to Cognitive Stress under Water

    Directory of Open Access Journals (Sweden)

    Hugo F. Posada-Quintero

    2018-01-01

    Full Text Available When divers are at depth in water, the high pressure and low temperature alone can cause severe stress, challenging the human physiological control systems. The addition of cognitive stress, for example during a military mission, exacerbates the challenge. In these conditions, humans are more susceptible to autonomic imbalance. Reliable tools for the assessment of the autonomic nervous system (ANS could be used as indicators of the relative degree of stress a diver is experiencing, which could reveal heightened risk during a mission. Electrodermal activity (EDA, a measure of the changes in conductance at the skin surface due to sweat production, is considered a promising alternative for the non-invasive assessment of sympathetic control of the ANS. EDA is sensitive to stress of many kinds. Therefore, as a first step, we tested the sensitivity of EDA, in the time and frequency domains, specifically to cognitive stress during water immersion of the subject (albeit with their measurement finger dry for safety. The data from 14 volunteer subjects were used from the experiment. After a 4-min adjustment and baseline period after being immersed in water, subjects underwent the Stroop task, which is known to induce cognitive stress. The time-domain indices of EDA, skin conductance level (SCL and non-specific skin conductance responses (NS.SCRs, did not change during cognitive stress, compared to baseline measurements. Frequency-domain indices of EDA, EDASymp (based on power spectral analysis and TVSymp (based on time-frequency analysis, did significantly change during cognitive stress. This leads to the conclusion that EDA, assessed by spectral analysis, is sensitive to cognitive stress in water-immersed subjects, and can potentially be used to detect cognitive stress in divers.

  18. Global gradients of coral exposure to environmental stresses and implications for local management.

    Directory of Open Access Journals (Sweden)

    Joseph Maina

    Full Text Available BACKGROUND: The decline of coral reefs globally underscores the need for a spatial assessment of their exposure to multiple environmental stressors to estimate vulnerability and evaluate potential counter-measures. METHODOLOGY/PRINCIPAL FINDINGS: This study combined global spatial gradients of coral exposure to radiation stress factors (temperature, UV light and doldrums, stress-reinforcing factors (sedimentation and eutrophication, and stress-reducing factors (temperature variability and tidal amplitude to produce a global map of coral exposure and identify areas where exposure depends on factors that can be locally managed. A systems analytical approach was used to define interactions between radiation stress variables, stress reinforcing variables and stress reducing variables. Fuzzy logic and spatial ordinations were employed to quantify coral exposure to these stressors. Globally, corals are exposed to radiation and reinforcing stress, albeit with high spatial variability within regions. Based on ordination of exposure grades, regions group into two clusters. The first cluster was composed of severely exposed regions with high radiation and low reducing stress scores (South East Asia, Micronesia, Eastern Pacific and the central Indian Ocean or alternatively high reinforcing stress scores (the Middle East and the Western Australia. The second cluster was composed of moderately to highly exposed regions with moderate to high scores in both radiation and reducing factors (Caribbean, Great Barrier Reef (GBR, Central Pacific, Polynesia and the western Indian Ocean where the GBR was strongly associated with reinforcing stress. CONCLUSIONS/SIGNIFICANCE: Despite radiation stress being the most dominant stressor, the exposure of coral reefs could be reduced by locally managing chronic human impacts that act to reinforce radiation stress. Future research and management efforts should focus on incorporating the factors that mitigate the effect of

  19. Impacts on quality-induced water scarcity: drivers of nitrogen-related water pollution transfer under globalization from 1995 to 2009

    Science.gov (United States)

    Wan, Liyang; Cai, Wenjia; Jiang, Yongkai; Wang, Can

    2016-07-01

    Globalization enables the transfer of impacts on water availability. We argue that the threat should be evaluated not only by decrease of quantity, but more importantly by the degradation of water quality in exporting countries. Grouping the world into fourteen regions, this paper establishes a multi-region input-output framework to calculate the nitrogen-related grey water footprint and a water quality-induced scarcity index caused by pollution, for the period of 1995 to 2009. It is discovered that grey water embodied in international trade has been growing faster than total grey water footprint. China, the USA and India were the three top grey water exporters which accounted for more than half the total traded grey water. Dilemma rose when China and India were facing highest grey water scarcity. The EU and the USA were biggest grey water importers that alleviated their water stress by outsourcing water pollution. A structural decomposition analysis is conducted to study the drivers to the evolution of virtual flows of grey water under globalization during the period of 1995 to 2009. The results show that despite the technical progress that offset the growth of traded grey water, structural effects under globalization including both evolution in the globalized economic system and consumption structure, together with consumption volume made a positive contribution. It is found that the structural effect intensified the pollution-induced water scarcity of exporters as it generally increased all nations’ imported grey water while resulting in increases in only a few nations’ exported grey water, such as Brazil, China and Indonesia. At last, drawing from the ‘cap-and-trade’ and ‘boarder-tax-adjustment’ schemes, we propose policy recommendations that ensure water security and achieve environmentally sustainable trade from both the sides of production and consumption.

  20. A Three-Dimensional Index for Characterizing Crop Water Stress

    Directory of Open Access Journals (Sweden)

    Jessica A. Torrion

    2014-05-01

    Full Text Available The application of remotely sensed estimates of canopy minus air temperature (Tc-Ta for detecting crop water stress can be limited in semi-arid regions, because of the lack of full ground cover (GC at water-critical crop stages. Thus, soil background may restrict water stress interpretation by thermal remote sensing. For partial GC, the combination of plant canopy temperature and surrounding soil temperature in an image pixel is expressed as surface temperature (Ts. Soil brightness (SB for an image scene varies with surface soil moisture. This study evaluates SB, GC and Ts-Ta and determines a fusion approach to assess crop water stress. The study was conducted (2007 and 2008 on a commercial scale, center pivot irrigated research site in the Texas High Plains. High-resolution aircraft-based imagery (red, near-infrared and thermal was acquired on clear days. The GC and SB were derived using the Perpendicular Vegetation Index approach. The Ts-Ta was derived using an array of ground Ts sensors, thermal imagery and weather station air temperature. The Ts-Ta, GC and SB were fused using the hue, saturation, intensity method, respectively. Results showed that this method can be used to assess water stress in reference to the differential irrigation plots and corresponding yield without the use of additional energy balance calculation for water stress in partial GC conditions.

  1. A global water supply reservoir yield model with uncertainty analysis

    International Nuclear Information System (INIS)

    Kuria, Faith W; Vogel, Richard M

    2014-01-01

    Understanding the reliability and uncertainty associated with water supply yields derived from surface water reservoirs is central for planning purposes. Using a global dataset of monthly river discharge, we introduce a generalized model for estimating the mean and variance of water supply yield, Y, expected from a reservoir for a prespecified reliability, R, and storage capacity, S assuming a flow record of length n. The generalized storage–reliability–yield (SRY) relationships reported here have numerous water resource applications ranging from preliminary water supply investigations, to economic and climate change impact assessments. An example indicates how our generalized SRY relationship can be combined with a hydroclimatic model to determine the impact of climate change on surface reservoir water supply yields. We also document that the variability of estimates of water supply yield are invariant to characteristics of the reservoir system, including its storage capacity and reliability. Standardized metrics of the variability of water supply yields are shown to depend only on the sample size of the inflows and the statistical characteristics of the inflow series. (paper)

  2. Co-regulation of water and K(+) transport in sunflower plants during water stress recovery.

    Science.gov (United States)

    Benlloch, Manuel; Benlloch-González, María

    2016-06-01

    16-day-old sunflower (Helianthus annuus L.) plants were subjected to deficit irrigation for 12 days. Following this period, plants were rehydrated for 2 days to study plant responses to post-stress recovery. The moderate water stress treatment applied reduced growth in all plant organs and the accumulation of K(+) in the shoot. After the rehydration period, the stem recovered its growth and reached a similar length to the control, an effect which was not observed in either root or leaves. Moreover, plant rehydration after water stress favored the accumulation of K(+) in the apical zone of the stem and expanding leaves. In the roots of plants under water stress, watering to field capacity, once the plants were de- topped, rapidly favored K(+) and water transport in the excised roots. This quick and short-lived response was not observed in roots of plants recovered from water stress for 2 days. These results suggest that the recovery of plant growth after water stress is related to coordinated water and K(+) transport from the root to the apical zone of the ​​stem and expanding leaves. This stimulation of K(+) transport in the root and its accumulation in the cells of the growing zones of the ​​stem must be one of the first responses induced in the plant during water stress recovery. Copyright © 2016 Elsevier GmbH. All rights reserved.

  3. Water requirements for livestock production: a global perspective.

    Science.gov (United States)

    Schlink, A C; Nguyen, M L; Viljoen, G J

    2010-12-01

    Water is a vital but poorly studied component of livestock production. It is estimated that livestock industries consume 8% of the global water supply, with most of that water being used for intensive, feed-based production. This study takes a broad perspective of livestock production as a component of the human food chain, and considers the efficiency of its water use. Global models are in the early stages of development and do not distinguish between developing and developed countries, or the production systems within them. However, preliminary indications are that, when protein production is adjusted for biological value in the human diet, no plant protein is significantly more efficient at using water than protein produced from eggs, and only soybean is more water efficient than milk and goat and chicken meat. In some regions, especially developing countries, animals are not used solely for food production but also provide draught power, fibre and fertiliser for crops. In addition, animals make use of crop by-products that would otherwise go to waste. The livestock sector is the fastest-growing agricultural sector, which has led to increasing industrialisation and, in some cases, reduced environmental constraints. In emerging economies, increasing involvement in livestock is related to improving rural wealth and increasing consumption of animal protein. Water usage for livestock production should be considered an integral part of agricultural water resource management, taking into account the type of production system (e.g. grain-fed or mixed crop-livestock) and scale (intensive or extensive), the species and breeds of livestock, and the social and cultural aspects of livestock farming in various countries.

  4. Effects of ultraviolet-B radiation on plants during mild water stress, 4: The insensitivity of soybean internal water relations to ultraviolet-B radiation

    International Nuclear Information System (INIS)

    Teramura, A.H.; Forseth, I.N.; Lydon, J.

    1984-01-01

    The combined effects of ultraviolet-B (UV-B, 280–320 nm) radiation and water stress were investigated on the water relations of greenhouse grown soybean [Glycine max (L.) Merr. cv. Essex]. On a weighted (Caldwell 1971), total daily dose basis, plants received either 0 or 3 000 effective J m 2 UV-B BE supplied by filtered FS-40 sunlamps. The latter dose simulated the solar UV-B radiation anticipated at College Park, Maryland, U.S.A. (39°N latitude) in the event that the global stratospheric ozone column is reduced by 25%. Plants were either well-watered or preconditioned by drought stress cycles. Diurnal measurements of water potential and stomatal conductance were made on the youngest fully expanded leaf. Various internal water relations parameters were determined for detached leaves. Plants were monitored before, during and after water stress. There were no significant differences in leaf water potential or stomatal conductance between treatments before plants were preconditioned to water stress. However, drought stress resulted in significantly lower midday and afternoon leaf water potentials and lower leaf conductances as compared to well-watered plants. UV-B radiation had no additional effect on leaf water potential; however, UV did result in lower leaf conductances in plants preconditioned to water stress. Turgid weight:dry weight ratio, elastic modulus, bound water and relative water content were unaffected by UV-B radiation. Osmotic potentials at full and zero turgor were significantly lower in the drought stressed treatments as compared to well-watered plants. (author)

  5. Improvements in crop water productivity increase water sustainability and food security—a global analysis

    International Nuclear Information System (INIS)

    Brauman, Kate A; Foley, Jonathan A; Siebert, Stefan

    2013-01-01

    Irrigation consumes more water than any other human activity, and thus the challenges of water sustainability and food security are closely linked. To evaluate how water resources are used for food production, we examined global patterns of water productivity—food produced (kcal) per unit of water (l) consumed. We document considerable variability in crop water productivity globally, not only across different climatic zones but also within climatic zones. The least water productive systems are disproportionate freshwater consumers. On precipitation-limited croplands, we found that ∼40% of water consumption goes to production of just 20% of food calories. Because in many cases crop water productivity is well below optimal levels, in many cases farmers have substantial opportunities to improve water productivity. To demonstrate the potential impact of management interventions, we calculated that raising crop water productivity in precipitation-limited regions to the 20th percentile of productivity would increase annual production on rainfed cropland by enough to provide food for an estimated 110 million people, and water consumption on irrigated cropland would be reduced enough to meet the annual domestic water demands of nearly 1.4 billion people. (letter)

  6. A water stress index based on water balance modelling for discrimination of grapevine quality and yield

    Directory of Open Access Journals (Sweden)

    Rémi Gaudin

    2014-01-01

    Significance and impact of the study: This water stress index is a valuable tool for explaining the variations in grape yield and quality among various locations and years because it reflects the vineyard water stress history in relation to rainfall regime and soil conditions. Improvement would come from the simulation of FTSW during winter, notably for soils of high Total Transpirable Soil Water. One potential application is the quantification of water stress change brought by irrigation in Mediterranean vineyards, and its relation to grapevine production.

  7. Genome-wide identification of differentially expressed genes under water deficit stress in upland cotton (Gossypium hirsutum L.).

    Science.gov (United States)

    Park, Wonkeun; Scheffler, Brian E; Bauer, Philip J; Campbell, B Todd

    2012-06-15

    Cotton is the world's primary fiber crop and is a major agricultural commodity in over 30 countries. Like many other global commodities, sustainable cotton production is challenged by restricted natural resources. In response to the anticipated increase of agricultural water demand, a major research direction involves developing crops that use less water or that use water more efficiently. In this study, our objective was to identify differentially expressed genes in response to water deficit stress in cotton. A global expression analysis using cDNA-Amplified Fragment Length Polymorphism was conducted to compare root and leaf gene expression profiles from a putative drought resistant cotton cultivar grown under water deficit stressed and well watered field conditions. We identified a total of 519 differentially expressed transcript derived fragments. Of these, 147 transcript derived fragment sequences were functionally annotated according to their gene ontology. Nearly 70 percent of transcript derived fragments belonged to four major categories: 1) unclassified, 2) stress/defense, 3) metabolism, and 4) gene regulation. We found heat shock protein-related and reactive oxygen species-related transcript derived fragments to be among the major parts of functional pathways induced by water deficit stress. Also, twelve novel transcripts were identified as both water deficit responsive and cotton specific. A subset of differentially expressed transcript derived fragments was verified using reverse transcription-polymerase chain reaction. Differential expression analysis also identified five pairs of duplicated transcript derived fragments in which four pairs responded differentially between each of their two homologues under water deficit stress. In this study, we detected differentially expressed transcript derived fragments from water deficit stressed root and leaf tissues in tetraploid cotton and provided their gene ontology, functional/biological distribution, and

  8. Global gene expression in cotton (Gossypium hirsutum L. leaves to waterlogging stress.

    Directory of Open Access Journals (Sweden)

    Yanjun Zhang

    Full Text Available Cotton is sensitive to waterlogging stress, which usually results in stunted growth and yield loss. To date, the molecular mechanisms underlying the responses to waterlogging in cotton remain elusive. Cotton was grown in a rain-shelter and subjected to 0 (control-, 10-, 15- and 20-d waterlogging at flowering stage. The fourth-leaves on the main-stem from the top were sampled and immediately frozen in liquid nitrogen for physiological measurement. Global gene transcription in the leaves of 15-d waterlogged plants was analyzed by RNA-Seq. Seven hundred and ninety four genes were up-regulated and 1018 genes were down-regulated in waterlogged cotton leaves compared with non-waterlogged control. The differentially expressed genes were mainly related to photosynthesis, nitrogen metabolism, starch and sucrose metabolism, glycolysis and plant hormone signal transduction. KEGG (Kyoto Encyclopedia of Genes and Genomes analysis indicated that most genes related to flavonoid biosynthesis, oxidative phosphorylation, amino acid metabolism and biosynthesis as well as circadian rhythm pathways were differently expressed. Waterlogging increased the expression of anaerobic fermentation related genes, such as alcohol dehydrogenase (ADH, but decreased the leaf chlorophyll concentration and photosynthesis by down-regulating the expression of photosynthesis related genes. Many genes related to plant hormones and transcription factors were differently expressed under waterlogging stress. Most of the ethylene related genes and ethylene-responsive factor-type transcription factors were up-regulated under water-logging stress, suggesting that ethylene may play key roles in the survival of cotton under waterlogging stress.

  9. The Community Water Model (CWATM) / Development of a community driven global water model

    Science.gov (United States)

    Burek, Peter; Satoh, Yusuke; Greve, Peter; Kahil, Taher; Wada, Yoshihide

    2017-04-01

    With a growing population and economic development, it is expected that water demands will increase significantly in the future, especially in developing regions. At the same time, climate change is expected to alter spatial patterns of hydrological cycle and will have global, regional and local impacts on water availability. Thus, it is important to assess water supply, water demand and environmental needs over time to identify the populations and locations that will be most affected by these changes linked to water scarcity, droughts and floods. The Community Water Model (CWATM) will be designed for this purpose in that it includes an accounting of how future water demands will evolve in response to socioeconomic change and how water availability will change in response to climate. CWATM represents one of the new key elements of IIASA's Water program. It has been developed to work flexibly at both global and regional level at different spatial resolutions. The model is open source and community-driven to promote our work amongst the wider water community worldwide and is flexible enough linking to further planned developments such as water quality and hydro-economic modules. CWATM will be a basis to develop a next-generation global hydro-economic modeling framework that represents the economic trade-offs among different water management options over a basin looking at water supply infrastructure and demand managements. The integrated modeling framework will consider water demand from agriculture, domestic, energy, industry and environment, investment needs to alleviate future water scarcity, and will provide a portfolio of economically optimal solutions for achieving future water management options under the Sustainable Development Goals (SDG) for example. In addition, it will be able to track the energy requirements associated with the water supply system e.g., pumping, desalination and interbasin transfer to realize the linkage with the water-energy economy. In

  10. Photosynthetic efficiency of Pedunculate oak seedlings under simulated water stress

    Directory of Open Access Journals (Sweden)

    Popović Zorica

    2010-01-01

    Full Text Available Photosynthetic performance of seedlings of Quercus robur exposed to short-term water stress in the laboratory conditions was assessed through the method of induced fluorometry. The substrate for seedlings was clayey loam, with the dominant texture fraction made of silt, followed by clay and fine sand, with total porosity 68.2%. Seedlings were separated in two groups: control (C (soil water regime in pots was maintained at the level of field water capacity and treated (water-stressed, WS (soil water regime was maintained in the range of wilting point and lentocapillary capacity. The photosynthetic efficiency was 0.642±0.25 and 0.522±0.024 (WS and C, respectively, which was mostly due to transplantation disturbances and sporadic leaf chlorosis. During the experiment Fv/Fm decreased in both groups (0.551±0.0100 and 0.427±0.018 in C and WS, respectively. Our results showed significant differences between stressed and control group, in regard to both observed parameters (Fv/Fm and T½. Photosynthetic efficiency of pedunculate oak seedlings was significantly affected by short-term water stress, but to a lesser extent than by sufficient watering.

  11. Global analysis of urban surface water supply vulnerability

    International Nuclear Information System (INIS)

    Padowski, Julie C; Gorelick, Steven M

    2014-01-01

    This study presents a global analysis of urban water supply vulnerability in 71 surface-water supplied cities, with populations exceeding 750 000 and lacking source water diversity. Vulnerability represents the failure of an urban supply-basin to simultaneously meet demands from human, environmental and agricultural users. We assess a baseline (2010) condition and a future scenario (2040) that considers increased demand from urban population growth and projected agricultural demand. We do not account for climate change, which can potentially exacerbate or reduce urban supply vulnerability. In 2010, 35% of large cities are vulnerable as they compete with agricultural users. By 2040, without additional measures 45% of cities are vulnerable due to increased agricultural and urban demands. Of the vulnerable cities in 2040, the majority are river-supplied with mean flows so low (1200 liters per person per day, l/p/d) that the cities experience ‘chronic water scarcity’ (1370 l/p/d). Reservoirs supply the majority of cities facing individual future threats, revealing that constructed storage potentially provides tenuous water security. In 2040, of the 32 vulnerable cities, 14 would reduce their vulnerability via reallocating water by reducing environmental flows, and 16 would similarly benefit by transferring water from irrigated agriculture. Approximately half remain vulnerable under either potential remedy. (letter)

  12. Alleviation of Water Stress Effects on MR220 Rice by Application of Periodical Water Stress and Potassium Fertilization

    Directory of Open Access Journals (Sweden)

    Nurul Amalina Mohd Zain

    2014-02-01

    Full Text Available The use of periodical water stress and potassium fertilization may enhance rice tolerance to drought stress and improve the crop’s instantaneous water use efficiency without much yield reduction. This study was conducted to assess the effects of different periodical water stress combined with potassium fertilization regimes on growth, yield, leaf gas exchanges and biochemical changes in rice grown in pots and compare them with standard local rice grower practices. Five treatments including (1 standard local grower’s practice (control, 80CF = 80 kg K2O/ha + control flooding; (2 120PW15 = 120 kg K2O/ha + periodical water stress for 15 days; (3 120DS15V = 120 kg K2O/ha + drought stress for 15 days during the vegetative stage; (4 120DS25V = 120 kg K2O/ha + drought stress for 25 days and (5 120DS15R = 120 kg K2O/ha + drought stress for 15 days during the reproductive stage, were evaluated in this experiment. Control and 120PW15 treatments were stopped at 100 DAS, and continuously saturated conditions were applied until harvest. It was found that rice under 120PW15 treatment showed tolerance to drought stress evidenced by increased water use efficiency, peroxidase (POX, catalase (CAT and proline levels, maximum efficiency of photosystem II (fv/fm and lower minimal fluorescence (fo, compared to other treatments. Path coefficient analysis revealed that most of parameters contribute directly rather than indirectly to rice yield. In this experiment, there were four factors that are directly involved with rice yield: grain soluble sugar, photosynthesis, water use efficiency and total chlorophyll content. The residual factors affecting rice yield are observed to be quite low in the experiment (0.350, confirming that rice yield was mostly influenced by the parameters measured during the study.

  13. Virtual water transfers unlikely to redress inequality in global water use

    International Nuclear Information System (INIS)

    Seekell, D A; D'Odorico, P; Pace, M L

    2011-01-01

    The distribution of renewable freshwater resources between countries is highly unequal and 80% of humanity lives in regions where water security is threatened. The transfer of agricultural and industrial products to areas where water is limited through global trade may have potential for redressing water imbalances. These transfers represent 'virtual water' used in commodity production. We evaluated the current water-use inequality between countries and the potential of virtual water transfers to equalize water use among nations using multiple statistical measures of inequality. Overall, the actual use of renewable water resources is relatively equal even though the physical distribution of renewable water resources is highly unequal. Most inequality (76%) in water use is due to agricultural production and can be attributed to climate and arable land availability, not social development status. Virtual water use is highly unequal and is almost completely explained by social development status. Virtual water transfer is unlikely to increase water-use equality primarily because agricultural water use dominates national water needs and cannot be completely compensated by virtual water transfers.

  14. Virtual water transfers unlikely to redress inequality in global water use

    Energy Technology Data Exchange (ETDEWEB)

    Seekell, D A; D' Odorico, P; Pace, M L [Department of Environmental Sciences, University of Virginia, Charlottesville, VA (United States)

    2011-04-15

    The distribution of renewable freshwater resources between countries is highly unequal and 80% of humanity lives in regions where water security is threatened. The transfer of agricultural and industrial products to areas where water is limited through global trade may have potential for redressing water imbalances. These transfers represent 'virtual water' used in commodity production. We evaluated the current water-use inequality between countries and the potential of virtual water transfers to equalize water use among nations using multiple statistical measures of inequality. Overall, the actual use of renewable water resources is relatively equal even though the physical distribution of renewable water resources is highly unequal. Most inequality (76%) in water use is due to agricultural production and can be attributed to climate and arable land availability, not social development status. Virtual water use is highly unequal and is almost completely explained by social development status. Virtual water transfer is unlikely to increase water-use equality primarily because agricultural water use dominates national water needs and cannot be completely compensated by virtual water transfers.

  15. A summary of global {sup 129}I in marine waters

    Energy Technology Data Exchange (ETDEWEB)

    He Peng, E-mail: peng.he@geo.uu.se [Dept. of Earth Sciences, Uppsala University, Villav. 16, 752 36 Uppsala (Sweden); Aldahan, A. [Dept. of Earth Sciences, Uppsala University, Villav. 16, 752 36 Uppsala (Sweden); Dept. of Geology, United Arab Emirates University, P.O. Box 17551, Al Ain (United Arab Emirates); Possnert, G. [Tandem Laboratory, Uppsala University, P.O. Box 529, 751 20 Uppsala (Sweden); Hou, X.L. [Riso National Laboratory for Sustainable Energy, NUK-202, Technical University of Denmark, DK-4000 Roskilde (Denmark)

    2013-01-15

    Despite the many investigations concerning the occurrence of anthropogenic iodine-129 in the atmosphere, terrestrial and marine environments, there is a lack of a comprehensive collection of data on the distribution of the isotope in marine waters. The temporal and spatial variability of anthropogenic {sup 129}I is strongly linked to the major point sources in the Irish Sea and the English Channel and the global marine spreading pathways are partly outlined from these sources. The temporal evolution is still, however, not well defined when transport and dissipation are considered in the different oceans and ocean compartments. We here summarize available published literature data on {sup 129}I temporal and spatial distribution in the global marine water. The results show presence of numerous data sets for the North Atlantic and Arctic Oceans where strong variability in terms of water depth, time and location also occur. Scarcity of data on {sup 129}I from the Pacific, Indian and South Atlantic Oceans demonstrates gaps in the coverage of the isotope spatial extent. These shortcomings in the spatial coverage may relate to the understanding that the anthropogenic {sup 129}I signal will take a long time to be transported, if at all, from the North Atlantic into other oceans. Data from recent expeditions in the Southern oceans and the Geotraces ocean profiling will reveal additional information about {sup 129}I distribution in the marine waters.

  16. A summary of global 129I in marine waters

    International Nuclear Information System (INIS)

    He Peng; Aldahan, A.; Possnert, G.; Hou, X.L.

    2013-01-01

    Despite the many investigations concerning the occurrence of anthropogenic iodine-129 in the atmosphere, terrestrial and marine environments, there is a lack of a comprehensive collection of data on the distribution of the isotope in marine waters. The temporal and spatial variability of anthropogenic 129 I is strongly linked to the major point sources in the Irish Sea and the English Channel and the global marine spreading pathways are partly outlined from these sources. The temporal evolution is still, however, not well defined when transport and dissipation are considered in the different oceans and ocean compartments. We here summarize available published literature data on 129 I temporal and spatial distribution in the global marine water. The results show presence of numerous data sets for the North Atlantic and Arctic Oceans where strong variability in terms of water depth, time and location also occur. Scarcity of data on 129 I from the Pacific, Indian and South Atlantic Oceans demonstrates gaps in the coverage of the isotope spatial extent. These shortcomings in the spatial coverage may relate to the understanding that the anthropogenic 129 I signal will take a long time to be transported, if at all, from the North Atlantic into other oceans. Data from recent expeditions in the Southern oceans and the Geotraces ocean profiling will reveal additional information about 129 I distribution in the marine waters.

  17. Temporal and spatial variability of global water balance

    Science.gov (United States)

    McCabe, Gregory J.; Wolock, David M.

    2013-01-01

    An analysis of simulated global water-balance components (precipitation [P], actual evapotranspiration [AET], runoff [R], and potential evapotranspiration [PET]) for the past century indicates that P has been the primary driver of variability in R. Additionally, since about 2000, there have been increases in P, AET, R, and PET for most of the globe. The increases in R during 2000 through 2009 have occurred despite unprecedented increases in PET. The increases in R are the result of substantial increases in P during the cool Northern Hemisphere months (i.e. October through March) when PET increases were relatively small; the largest PET increases occurred during the warm Northern Hemisphere months (April through September). Additionally, for the 2000 through 2009 period, the latitudinal distribution of P departures appears to co-vary with the mean P departures from 16 climate model projections of the latitudinal response of P to warming, except in the high latitudes. Finally, changes in water-balance variables appear large from the perspective of departures from the long-term means. However, when put into the context of the magnitudes of the raw water balance variable values, there appears to have been little change in any of the water-balance variables over the past century on a global or hemispheric scale.

  18. NMR imaging of water uptake in multilayer polymeric films : stressing the role of mechanical stress

    NARCIS (Netherlands)

    Baukh, V.; Huinink, H.P.; Adan, O.C.G.; Erich, S.J.F.; Ven, van der L.G.J.

    2010-01-01

    The penetration of water into two-layer polymeric films of a hydrophilic base layer and hydrophobic top layer plays an important role in their performance. Little is known about the coupled effects of water uptake and stress in such films. To study such interactive phenomena, time-dependent

  19. Global Water Cycle Diagrams Minimize Human Influence and Over-represent Water Security

    Science.gov (United States)

    Abbott, B. W.; Bishop, K.; Zarnetske, J. P.; Minaudo, C.; Chapin, F. S., III; Plont, S.; Marçais, J.; Ellison, D.; Roy Chowdhury, S.; Kolbe, T.; Ursache, O.; Hampton, T. B.; GU, S.; Chapin, M.; Krause, S.; Henderson, K. D.; Hannah, D. M.; Pinay, G.

    2017-12-01

    The diagram of the global water cycle is the central icon of hydrology, and for many people, the point of entry to thinking about key scientific concepts such as conservation of mass, teleconnections, and human dependence on ecological systems. Because humans now dominate critical components of the hydrosphere, improving our understanding of the global water cycle has graduated from an academic exercise to an urgent priority. To assess how the water cycle is conceptualized by researchers and the general public, we analyzed 455 water cycle diagrams from textbooks, scientific articles, and online image searches performed in different languages. Only 15% of diagrams integrated human activity into the water cycle and 77% showed no sign of humans whatsoever, although representation of humans varied substantially by region (lowest in China, N. America, and Australia; highest in Western Europe). The abundance and accessibility of freshwater resources were overrepresented, with 98% of diagrams omitting water pollution and climate change, and over 90% of diagrams making no distinction for saline groundwater and lakes. Oceanic aspects of the water cycle (i.e. ocean size, circulation, and precipitation) and related teleconnections were nearly always underrepresented. These patterns held across disciplinary boundaries and through time. We explore the historical and contemporary reasons for some of these biases and present a revised version of the global water cycle based on research from natural and social sciences. We conclude that current depictions of the global water cycle convey a false sense of water security and that reintegrating humans into water cycle diagrams is an important first step towards understanding and sustaining the hydrosocial cycle.

  20. Will climate change exacerbate water stress in Central Asia?

    DEFF Research Database (Denmark)

    Siegfried, Tobias; Bernauer, Thomas; Guiennet, Renaud

    2012-01-01

    the Soviet Union collapsed. Will climate change exacerbate water stress and thus conflicts? We have developed a coupled climate, land-ice and rainfall-runoff model for the Syr Darya to quantify impacts and show that climatic changes are likely to have consequences on runoff seasonality due to earlier snow......-melt. This will increase water stress in unregulated catchments because less water will be available for irrigation in the summer months. Threats from geohazards, above all glacier lake outbursts, are likely to increase as well. The area at highest risk is the densely populated, agriculturally productive, and politically......Millions of people in the geopolitically important region of Central Asia depend on water from snow- and glacier-melt driven international rivers, most of all the Syr Darya and Amu Darya. The riparian countries of these rivers have experienced recurring water allocation conflicts ever since...

  1. Chlorine stress mediates microbial surface attachment in drinking water systems.

    Science.gov (United States)

    Liu, Li; Le, Yang; Jin, Juliang; Zhou, Yuliang; Chen, Guowei

    2015-03-01

    Microbial attachment to drinking water pipe surfaces facilitates pathogen survival and deteriorates disinfection performance, directly threatening the safety of drinking water. Notwithstanding that the formation of biofilm has been studied for decades, the underlying mechanisms for the origins of microbial surface attachment in biofilm development in drinking water pipelines remain largely elusive. We combined experimental and mathematical methods to investigate the role of environmental stress-mediated cell motility on microbial surface attachment in chlorination-stressed drinking water distribution systems. Results show that at low levels of disinfectant (0.0-1.0 mg/L), the presence of chlorine promotes initiation of microbial surface attachment, while higher amounts of disinfectant (>1.0 mg/L) inhibit microbial attachment. The proposed mathematical model further demonstrates that chlorination stress (0.0-5.0 mg/L)-mediated microbial cell motility regulates the frequency of cell-wall collision and thereby controls initial microbial surface attachment. The results reveal that transport processes and decay patterns of chlorine in drinking water pipelines regulate microbial cell motility and, thus, control initial surface cell attachment. It provides a mechanistic understanding of microbial attachment shaped by environmental disinfection stress and leads to new insights into microbial safety protocols in water distribution systems.

  2. Modeling spatially- and temporally-explicit water stress indices for use in life cycle assessment

    Science.gov (United States)

    Scherer, L.; Venkatesh, A.; Karuppiah, R.; Usadi, A.; Pfister, S.; Hellweg, S.

    2013-12-01

    Water scarcity is a regional issue in many areas across the world, and can affect human health and ecosystems locally. Water stress indices (WSIs) have been developed as quantitative indicators of such scarcities - examples include the Falkenmark indicator, Social Water Stress Index, and the Water Supply Stress Index1. Application of these indices helps us understand water supply and demand risks for multiple users, including those in the agricultural, industrial, residential and commercial sectors. Pfister et al.2 developed a method to calculate WSIs that were used to estimate characterization factors (CFs) in order to quantify environmental impacts of freshwater consumption within a life cycle assessment (LCA) framework. Global WSIs were based on data from the WaterGAP model3, and presented as annual averages for watersheds. Since water supply and demand varies regionally and temporally, the resolution used in Pfister et al. does not effectively differentiate between seasonal and permanent water scarcity. This study aims to improve the temporal and spatial resolution of the water scarcity calculations used to estimate WSIs and CFs. We used the Soil and Water Assessment Tool (SWAT)4 hydrological model to properly simulate water supply in different world regions with high spatial and temporal resolution, and coupled it with water use data from WaterGAP3 and Pfister et al.5. Input data to SWAT included weather, land use, soil characteristics and a digital elevation model (DEM), all from publicly available global data sets. Potential evapotranspiration, which affects water supply, was determined using an improved Priestley-Taylor approach. In contrast to most other hydrological studies, large reservoirs, water consumption and major water transfers were simulated. The model was calibrated against observed monthly discharge, actual evapotranspiration, and snow water equivalents wherever appropriate. Based on these simulations, monthly WSIs were calculated for a few

  3. Effect of water impurities on stress corrosion cracking in a boiling water reactor

    International Nuclear Information System (INIS)

    Ljungbery, L.G.; Cubicciotti, D

    1985-01-01

    A series of stress corrosion tests, including corrosion potential and water chemistry measurements, has been performed in the Swedish Ringhals-1 boiling water reactor. Tests have been run under reactor start-up and reactor power operation with normal reactor water conditions and with alternate water chemistry in which hydrogen is added to the feedwater to suppress stress corrosion cracking. During one alternate water chemistry test, there was significant intergranular corrosion cracking of sensitized stainless specimens. It is shown that nitrate and sulfate, arising from an accidental resin intrusion, are likely causes. Nitrate increases the oxidizing power of the water, and sulfate enhances cracking under oxidizing conditions. During another test under start-up conditions, enhanced transgranular stress corrosion cracking in low alloy steels and possibly initiation of cracking in a nickel base alloy was observed as a result of resin intrusion into the reactor water. The intrusion produced acid and sulfate, which are believed to enhance hydrogen cracking conditions

  4. Agricultural insecticides threaten surface waters at the global scale.

    Science.gov (United States)

    Stehle, Sebastian; Schulz, Ralf

    2015-05-05

    Compared with nutrient levels and habitat degradation, the importance of agricultural pesticides in surface water may have been underestimated due to a lack of comprehensive quantitative analysis. Increasing pesticide contamination results in decreasing regional aquatic biodiversity, i.e., macroinvertebrate family richness is reduced by ∼30% at pesticide concentrations equaling the legally accepted regulatory threshold levels (RTLs). This study provides a comprehensive metaanalysis of 838 peer-reviewed studies (>2,500 sites in 73 countries) that evaluates, for the first time to our knowledge on a global scale, the exposure of surface waters to particularly toxic agricultural insecticides. We tested whether measured insecticide concentrations (MICs; i.e., quantified insecticide concentrations) exceed their RTLs and how risks depend on insecticide development over time and stringency of environmental regulation. Our analysis reveals that MICs occur rarely (i.e., an estimated 97.4% of analyses conducted found no MICs) and there is a complete lack of scientific monitoring data for ∼90% of global cropland. Most importantly, of the 11,300 MICs, 52.4% (5,915 cases; 68.5% of the sites) exceeded the RTL for either surface water (RTLSW) or sediments. Thus, the biological integrity of global water resources is at a substantial risk. RTLSW exceedances depend on the catchment size, sampling regime, and sampling date; are significantly higher for newer-generation insecticides (i.e., pyrethroids); and are high even in countries with stringent environmental regulations. These results suggest the need for worldwide improvements to current pesticide regulations and agricultural pesticide application practices and for intensified research efforts on the presence and effects of pesticides under real-world conditions.

  5. HydroGrid: Technologies for Global Water Quality and Sustainability

    Science.gov (United States)

    Yeghiazarian, L.

    2017-12-01

    Humans have been transforming planet Earth for millennia. We have recently come to understand that the collective impact of our decisions and actions has brought about severe water quality problems, which are likely to worsen in the light of rapid population growth to the projected nine billion by 2050. To sustainably manage our global water resources and possibly reverse these effects requires efforts in real-time monitoring of water contamination, analysis of monitoring data, and control of the state of water contamination. We develop technologies to address all three areas: monitoring, analysis and control. These efforts are carried out in the conceptual framework of the HydroGrid, an interconnected water system, which is (1) firmly rooted in the fundamental understanding of processes that govern microbial dynamics on multiple scales; and (2) used to develop watershed-specific management strategies. In the area of monitoring we are developing mobile autonomous sensors to detect surface water contamination, an effort supported by extensive materials research to provide multifunctional materials. We analyze environmental data within a stochastic modeling paradigm that bridges microscopic particle interactions to macroscopic manifestation of microbial population behavior in time and space in entire watersheds. These models are supported with laboratory and field experiments. Finally, we combine control and graph theories to derive controllability metrics of natural watersheds.

  6. Airborne thermography for crop water stress assessment

    Science.gov (United States)

    Millard, J. P.; Idso, S. B.; Reginato, R. J.; Jackson, R. D.; Ehrler, W. L.; Goettelman, R. C.

    1977-01-01

    Aircraft overflights to obtain canopy temperatures of six differentially irrigated plots of durum wheat were made at Phoenix, Arizona on 1 and 29 April 1976. The data were acquired by a Texas Instruments model RS-25 infrared line scanner operating in the 8 to 14 micrometer bandpass region. Concurrently, plant water tension was measured on the ground with the Scholander pressure bomb technique. The results indicated that canopy temperatures acquired by aircraft about an hour and a half past solar noon correlated well with presunrise plant water tension - a parameter directly related to plant growth and development. The aircraft data also showed significant within-field canopy temperature variability, indicating the superiority of the synoptic view provided by aircraft over the more spotty view obtained by ground-operated infrared thermometers.

  7. Dextran's effects on stressed lenses: water, electrolyte, and radioisotope studies

    International Nuclear Information System (INIS)

    Sanders, D.R.; Bokosky, J.; Peyman, G.A.; Gray, D.

    1979-01-01

    To evaluate the beneficial effects of dextran 40 as an additive to infusion solutions, we studied an experimental model of lens stress with use of buffered, low calcium (Ca ++ )-containing solutions. Incubation in low Ca ++ solutions (pCa = 10.7) for ten hours (stress period) resulted in lens swelling and electrolyte imbalances that were irreversible even with reincubation in physiologic, normal Ca ++ -containing media (pCa = 2.7) (recovery period). The addition of 6% or more of dextran to the media inhibited lens water gain during the stress period. It also rendered the resultant electrolyte imbalances reversible during the recovery period, thus exerting a protective effect. Radioisotope-tracer studies showed that dextran improved the ability of the lens to accumulate rubidium chloride Rb 86 and reduced its efflux during both the stress and recovery periods. Dextran did not markedly decrease sodium chloride Na 22 uptake by lenses under stress

  8. Response of CO and H2 uptake to extremes of water stress in saline and non-saline soils

    Science.gov (United States)

    King, G.

    2017-12-01

    Neither carbon monoxide (CO) nor hydrogen (H2) have direct impacts on radiative forcing, but both play important roles in tropospheric chemistry. Soils affect both the fate and significance of atmospheric CO and H2 by acting as strong global gas sinks ( 15% and >75 %, respectively), but much remains unknown about the microbiology of these gases, including responses to key environmental drivers. The role of water availability, measured as water potential, has been addressed to a limited extent by earlier studies with results suggesting that CO and H2 uptake are strongly limited by water stress. However recent results indicate a much greater tolerance of water stress than previously suspected. Ex situ assays have shown that non-saline playa soils from the Alvord Basin (Oregon, USA) consumed atmospheric and exogenous hydrogen and CO under conditions of severe water stress. CO uptake occurred at water potentials values considered optimal for terrestrial bacterial growth. Surface soils that had been exposed to water potentials as low as -300 MPa also oxidized CO and H2 after brief equilibration at higher potentials (less water stress), indicating remarkable tolerance of desiccating conditions. Tolerance to water stress for CO and H2 uptake was also observed for soils from a montane rainforest (Hawai`i, USA). However, unlike playa soils rainforest soils seldom experience extended drought that would select for desiccation tolerance. While CO uptake by forest soils was more sensitive to water stress (limits -10MPa) than in playa soils, H2 uptake was observed at -90 MPa to -100 MPa. Tolerance at these levels might be due to the formation of intracellular water that limits the local effects of stress. Comparisons of water stress responses between saline and non-saline soils further suggested that communities of CO- and H2-oxidizing were generally robust with respect to stresses resulting from solute and matric effects. Collectively the results indicate that models of global

  9. Climate change, livelihoods and the multiple determinants of water adequacy: two approaches at regional to global scale

    Science.gov (United States)

    Lissner, Tabea; Reusser, Dominik

    2015-04-01

    Inadequate access to water is already a problem in many regions of the world and processes of global change are expected to further exacerbate the situation. Many aspects determine the adequacy of water resources: beside actual physical water stress, where the resource itself is limited, economic and social water stress can be experienced if access to resource is limited by inadequate infrastructure, political or financial constraints. To assess the adequacy of water availability for human use, integrated approaches are needed that allow to view the multiple determinants in conjunction and provide sound results as a basis for informed decisions. This contribution proposes two parts of an integrated approach to look at the multiple dimensions of water scarcity at regional to global scale. These were developed in a joint project with the German Development Agency (GIZ). It first outlines the AHEAD approach to measure Adequate Human livelihood conditions for wEll-being And Development, implemented at global scale and at national resolution. This first approach allows viewing impacts of climate change, e.g. changes in water availability, within the wider context of AHEAD conditions. A specific focus lies on the uncertainties in projections of climate change and future water availability. As adequate water access is not determined by water availability alone, in a second step we develop an approach to assess the water requirements for different sectors in more detail, including aspects of quantity, quality as well as access, in an integrated way. This more detailed approach is exemplified at region-scale in Indonesia and South Africa. Our results show that in many regions of the world, water scarcity is a limitation to AHEAD conditions in many countries, regardless of differing modelling output. The more detailed assessments highlight the relevance of additional aspects to assess the adequacy of water for human use, showing that in many regions, quality and

  10. Globally significant greenhouse-gas emissions from African inland waters

    Science.gov (United States)

    Borges, Alberto V.; Bouillon, Steven

    2017-04-01

    The relevance of inland waters to global biogeochemical cycles is increasingly recognized, and of particular importance is their contribution of greenhouse gases to the atmosphere. The latter remain largely unreported in African inland waters. Here we report dissolved CO2, CH4 and N2O from 12 rivers in Sub-Saharan Africa acquired during >30 field expeditions and additional seasonally resolved sampling at >30 sites between 2006 and 2014. Fluxes were calculated from reported gas transfer velocity values, and upscaled using available spatial datasets, with an estimated uncertainty of about ±19%. CO2 equivalent emissions ( 0.4±0.1 PgC yr-1) match 2/3 of the overall net carbon sink previously reported for Africa. Including emissions from wetlands of the Congo, the putative total emission ( 0.9±0.1 PgC yr-1) is about half of the global oceanic or land carbon sinks. In-situ respiration supported <14% of riverine CO2 emissions, which must therefore largely be driven by mineralization in wetlands or uplands. Riverine CO2 and CH4 emissions were directly correlated to wetland coverage and aboveground vegetation biomass, implying that future changes in wetland and upland vegetation cover will strongly impact GHG emissions from African inland waters.

  11. Global Water Scarcity Assessment under Post-SRES Scenarios

    Science.gov (United States)

    Hanasaki, N.; Fujimori, S.

    2011-12-01

    A large number of future projections contributed to the fourth Assessment Report of IPCC were based on Special Report on Emission Scenarios (SRES). Processes toward the fifth Assessment Report are under way, and post-SRES scenarios, called Shared Socio-economic Pathways (SSP) are being prepared. One of the key challenges of SSP is provision of detailed socio-economic scenarios compared to SRES for impact, adaptation and vulnerability studies. In this study, a comprehensive global water scarcity assessment was conducted, using a state of the art global water resources model H08 (Hanasaki et al., 2008a, 2008b, 2010). We used a prototype of SSP developed by National Institute for Environmental Studies, Japan. Two sets of socio economic scenarios and two sets of climate scenarios were prepared to run H08 for the period 2001-2100. Socio-economic scenarios include Business As Usual and High Mitigation Capacity. Climate scenarios include Reference and Mitigation which stabilizes green house gas concentration at a certain level. We analyzed the simulation results of four combinations, particularly focusing on the sensitivity of socio-economic scenarios to major water resources indices.

  12. Closing of water circuits – a global benchmark on sustainable water management

    Directory of Open Access Journals (Sweden)

    Fröhlich Siegmund

    2017-01-01

    Full Text Available Access to clean water resources has always been a crucial factor in the history of mankind. Now, in the 21st century, water, as an increasingly scarce resource, will take a strategic role for the future development of global populations. As the former UN Secretary General Dr. Dr. Boutrous Boutrous Ghali predicts: “The wars of the 21st century will be fought not over oil, they will be fought over water.” [1]. In nine global examples will be demonstrated the different ways of dealing with water resources. That are: Mexico City, Egypt, Libya, DOW Terneuzen, Los Angeles, Israel, China and Singapore and also global trends, such as, scarcity & rural exodus and salinization of soil. Thereby, he explains the different kinds of water management to be observed. The most relevant prognosis of the WHO is, that to the end of 21st century Africa's population will grow over proportionally from 1 billion now up to nearly 4 billion [9]. That is why all efforts need to be concentrated on helping Africa create a sustainable economic development. The first and by far most important strategic step is to assure access to clean water resources in the rural and mostly arid regions of the continent. The lecturer shows several technological proposals on how to overcame problems like: water scarcity, rural exodus, salinization of soil and others. Such technologies could be successfully implemented in sustainable development programs in African countries.

  13. Closing of water circuits - a global benchmark on sustainable water management

    Science.gov (United States)

    Fröhlich, Siegmund

    2017-11-01

    Access to clean water resources has always been a crucial factor in the history of mankind. Now, in the 21st century, water, as an increasingly scarce resource, will take a strategic role for the future development of global populations. As the former UN Secretary General Dr. Dr. Boutrous Boutrous Ghali predicts: "The wars of the 21st century will be fought not over oil, they will be fought over water." [1]. In nine global examples will be demonstrated the different ways of dealing with water resources. That are: Mexico City, Egypt, Libya, DOW Terneuzen, Los Angeles, Israel, China and Singapore and also global trends, such as, scarcity & rural exodus and salinization of soil. Thereby, he explains the different kinds of water management to be observed. The most relevant prognosis of the WHO is, that to the end of 21st century Africa's population will grow over proportionally from 1 billion now up to nearly 4 billion [9]. That is why all efforts need to be concentrated on helping Africa create a sustainable economic development. The first and by far most important strategic step is to assure access to clean water resources in the rural and mostly arid regions of the continent. The lecturer shows several technological proposals on how to overcame problems like: water scarcity, rural exodus, salinization of soil and others. Such technologies could be successfully implemented in sustainable development programs in African countries.

  14. Mobilization strategy to overcome global crisis of water consumption

    Science.gov (United States)

    Suzdaleva, Antonina; Goryunova, Svetlana; Marchuk, Aleksey; Borovkov, Valery

    2017-10-01

    Today, the global water consumption crisis is one of the main threats that can disrupt socio-economic and environmental conditions of life of the majority of the world’s population. The water consumption mobilization strategy is based on the idea of increasing the available water resources. The main direction for the implementation of this strategy is the construction of anti-rivers - the systems for inter-basin (interregional) water resources redistribution. Antirivers are intended for controlled redistribution of water resources from regions with their catastrophic excess to regions with their critical shortage. The creation of anti-rivers, taking into account the requirements of environmental safety, will form large-scale managed natural- engineering systems and implement the principle of sustainable development adopted by the United Nations. The aim of the article is to substantiate a new methodological approach to address the problem, where the implementation of this approach can prevent large-scale humanitarian and environmental disasters expected in the coming years.

  15. Influence of water stress on Botryosphaeriaceae disease expression in grapevines

    Directory of Open Access Journals (Sweden)

    Jan VAN NIEKERK

    2011-12-01

    Full Text Available Several species in Botryosphaeriaceae have been associated with grapevine trunk diseases. To evaluate the effect of water stress on infection of grapevines by Botryosphaeriaceae spp., 1-year-old Shiraz/101-14 Mgt nursery grapevine plants were planted in plastic potting bags and placed outdoors under shade netting. Five weeks after planting, vines were pruned and the pruning wounds inoculated with spore suspensions of Neofusicoccum australe, Neofusicoccum parvum, Lasiodiplodia theobromae or Diplodia seriata. Control treatments consisted of applications of sterile water or a Trichoderma harzianum spore suspension. Stem inoculations were done by inserting a colonised or uncolonised agar plug into a wound made in each stem. Four different irrigation regimes were introduced 12 weeks after planting to simulate varying degrees of water stress. Measurements of stomatal conductance, photosynthetic rate and leaf spectrometry were made to monitor physiological stress. Eight months after inoculation, vines were uprooted and the root, shoot and plant mass of each vine determined. Lesions observed in the inoculated pruning wounds and stems were also measured. Vines subjected to the lowest irrigation regime were significantly smaller than optimally irrigated vines. Water stressed vines also had significantly lower photosynthetic rates and levels of stomatal conductance compared with vines receiving optimal irrigation, indicating that these plants experienced significantly higher levels of physiological stress. The mean lesion length was significantly longer in the pruning wounds and stems of plants subjected to the lowest irrigation regime, with lesion length declining linearly with increasing irrigation volume. These results clearly indicate that when a grapevine is exposed to water stress, colonisation and disease expression by Botryosphaeriaceae spp. are much more severe.

  16. GEWEX - The Global Energy and Water Cycle Experiment

    Science.gov (United States)

    Chahine, Moustafa T.

    1992-01-01

    GEWEX, which is part of the World Climate Research Program, has as its goal an order-of-magnitude improvement in the ability to model global precipitation and evaporation and furnish an accurate assessment of the sensitivity of atmospheric radiation and clouds. Attention will also be given to the response of the hydrological cycle and water resources to climate change. GEWEX employs a single program to coordinate all aspects of climatology from model development to the deployment and operation of observational systems. GEWEX will operate over the next two decades.

  17. Cryosphere, climate and capitalism: drivers of Central Asian water stress

    Science.gov (United States)

    Hill, A. F.; Minbaeva, C.; Wilson, A. M.; Satylkanov, R.; Armstrong, R. L.

    2017-12-01

    The importance of meltwater to Central Asia's trans-boundary rivers and groundwater reserves suggests future water stress for the region. Climate is likely to induce shifts in water supply volume and delivery timing, while a complex fabric of socio-political factors complicates water management and adaptation strategies. To clarify the drivers of water stress over a large scale (440km, 4,200m elevation change), we conducted a socio-hydrologic study of Krygyzstan's Naryn River in the Tien Shan mountains, headwater stem of the Syr Darya and source of the disappearing Aral Sea. Using a combination of geochemical sampling, hydro-chemical mixing models, remote sensing image processing and community surveys, we characterized both the social and hydrologic controls of water supplies from glacier snout to downstream areas where people, hydropower and agriculture utilize water. We find melt-sourced water dominates hydrologic inputs to both surface flow and groundwater from headwaters to reservoir, suggesting high sensitivity of water supply to a warming climate. On a regional scale, the importance of melt to trans-boundary river flow serving thirsty downstream countries may increase hostility between already tense neighbors. Water stress on the basin level, however, is currently less impacted by supply than by access, agricultural knowledge deficiencies and infrastructure issues that are relic from the post-Soviet transition in the 1990s. The interplay of these factors suggests the need for creative and proactive water management adaptation planning in the Naryn basin and throughout similar melt-reliant areas of arid Central Asia.

  18. Physiological Assessment of Water Stress in Potato Using Spectral Information.

    Science.gov (United States)

    Romero, Angela P; Alarcón, Andrés; Valbuena, Raúl I; Galeano, Carlos H

    2017-01-01

    Water stress in potato ( Solanum tuberosum L.) causes considerable losses in yield, and therefore, potato is often considered to be a drought sensitive crop. Identification of water deficit tolerant potato genotypes is an adaptation strategy to mitigate the climatic changes that are occurring in the Cundiboyacense region in Colombia. Previous studies have evaluated potato plants under water stress conditions using physiological analyses. However, these methodologies require considerable amounts of time and plant material to perform these measurements. This study evaluated and compared the physiological and spectral traits between two genotypes, Diacol Capiro and Perla Negra under two drought levels (10 and 15 days without irrigation from flowering). Reflectance information was used to calculate indexes which were associated with the physiological behavior in plants. The results showed that spectral information was correlated (ρ < 0.0001) with physiological variables such as foliar area (FA), total water content (H 2 Ot), relative growth rate of potato tubers (RGTtub), leaf area ratio (LAR), and foliar area index (AFI). In general, there was a higher concentration of chlorophyll under drought treatments. In addition, Perla Negra under water deficit treatments did not show significant differences in its physiological variables. Therefore, it could be considered a drought tolerant genotype because its physiological performance was not affected under water stress conditions. However, yield was affected in both genotypes after being subject to 15 days of drought. The results suggested that reflectance indexes are a useful and affordable approach for potato phenotyping to select parent and segregant populations in breeding programs.

  19. Information processing speed as a mediator between psychosocial stress and global cognition in older adults.

    Science.gov (United States)

    Foong, Hui F; Hamid, Tengku A; Ibrahim, Rahimah; Haron, Sharifah A

    2018-01-01

    The link between psychosocial stress and cognitive function is complex, and previous studies have indicated that it may be mediated by processing speed. Therefore, the main aim of this study was to examine whether processing speed mediates the association between psychosocial stress and global cognition in older adults. Moreover, the moderating role of gender in this model is examined as well. The study included 2322 community-dwelling older adults in Malaysia who were randomly selected through a multistage proportional cluster random sampling technique. Global cognition construct was measured by the Mini-Mental State Examination and Montreal Cognitive Assessment; psychosocial stress construct was measured by perceived stress, depression, loneliness, and neuroticism; and processing speed was assessed by the Digit Symbol Substitution Test. Structural equation modelling was used to analyze the mediation and moderation tests. Processing speed was found to partially mediate the relationship between psychosocial stress and global cognition (β in the direct model = -0.15, P cognition was found to be significant in men only, whereas the association between processing speed and global cognition was significant in men and women. Psychosocial stress may increase the likelihood that older adults will experience poor processing capacity, which could reduce their higher level cognition. Results indicate that there is a need to develop processing capacity intervention programmes for psychologically distressed older adults to prevent them from suffering cognitive decline. © 2018 Japanese Psychogeriatric Society.

  20. Increasing water cycle extremes in California and in relation to ENSO cycle under global warming

    Science.gov (United States)

    Yoon, Jin-Ho; Wang, S-Y Simon; Gillies, Robert R.; Kravitz, Ben; Hipps, Lawrence; Rasch, Philip J.

    2015-01-01

    Since the winter of 2013–2014, California has experienced its most severe drought in recorded history, causing statewide water stress, severe economic loss and an extraordinary increase in wildfires. Identifying the effects of global warming on regional water cycle extremes, such as the ongoing drought in California, remains a challenge. Here we analyse large-ensemble and multi-model simulations that project the future of water cycle extremes in California as well as to understand those associations that pertain to changing climate oscillations under global warming. Both intense drought and excessive flooding are projected to increase by at least 50% towards the end of the twenty-first century; this projected increase in water cycle extremes is associated with a strengthened relation to El Niño and the Southern Oscillation (ENSO)—in particular, extreme El Niño and La Niña events that modulate California's climate not only through its warm and cold phases but also its precursor patterns. PMID:26487088

  1. Global change and modern coral reefs: New opportunities to understand shallow-water carbonate depositional processes

    Science.gov (United States)

    Hallock, Pamela

    2005-04-01

    Human activities are impacting coral reefs physically, biologically, and chemically. Nutrification, sedimentation, chemical pollution, and overfishing are significant local threats that are occurring worldwide. Ozone depletion and global warming are triggering mass coral-bleaching events; corals under temperature stress lose the ability to synthesize protective sunscreens and become more sensitive to sunlight. Photo-oxidative stress also reduces fitness, rendering reef-building organisms more susceptible to emerging diseases. Increasing concentration of atmospheric CO 2 has already reduced CaCO 3 saturation in surface waters by more than 10%. Doubling of atmospheric CO 2 concentration over pre-industrial concentration in the 21st century may reduce carbonate production in tropical shallow marine environments by as much as 80%. As shallow-water reefs decline worldwide, opportunities abound for researchers to expand understanding of carbonate depositional systems. Coordinated studies of carbonate geochemistry with photozoan physiology and calcification, particularly in cool subtropical-transition zones between photozoan-reef and heterotrophic carbonate-ramp communities, will contribute to understanding of carbonate sedimentation under environmental change, both in the future and in the geologic record. Cyanobacteria are becoming increasingly prominent on declining reefs, as these microbes can tolerate strong solar radiation, higher temperatures, and abundant nutrients. The responses of reef-dwelling cyanobacteria to environmental parameters associated with global change are prime topics for further research, with both ecological and geological implications.

  2. Water stress induced changes in antioxidant enzymes, membrane ...

    African Journals Online (AJOL)

    Water stress induced changes in antioxidant enzymes membrane stablity index and seed protein profiling of four different wheat (Triticum aestivum L.) accessions (011251, 011417, 011320 and 011393) were determined in a pot study under natural condition during the wheat-growing season 2005 and 2006. Sampling was ...

  3. Biomass production and potential water stress increase with ...

    African Journals Online (AJOL)

    The choice of planting density and tree genotype are basic decisions when establishing a forest stand. Understanding the interaction between planting density and genotype, and their relationship with biomass production and potential water stress, is crucial as forest managers are faced with a changing climate. However ...

  4. Water stress strengthens mutualism among ants, trees, and scale insects.

    Directory of Open Access Journals (Sweden)

    Elizabeth G Pringle

    2013-11-01

    Full Text Available Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant-plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners' investments in a widespread ant-plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism.

  5. Water Stress Strengthens Mutualism Among Ants, Trees, and Scale Insects

    Science.gov (United States)

    Pringle, Elizabeth G.; Akçay, Erol; Raab, Ted K.; Dirzo, Rodolfo; Gordon, Deborah M.

    2013-01-01

    Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant–plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners' investments in a widespread ant–plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism. PMID:24223521

  6. Water stress strengthens mutualism among ants, trees, and scale insects.

    Science.gov (United States)

    Pringle, Elizabeth G; Akçay, Erol; Raab, Ted K; Dirzo, Rodolfo; Gordon, Deborah M

    2013-11-01

    Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant-plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners' investments in a widespread ant-plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism.

  7. Agricultural production and water use scenarios in Cyprus under global change

    Science.gov (United States)

    Bruggeman, Adriana; Zoumides, Christos; Camera, Corrado; Pashiardis, Stelios; Zomeni, Zomenia

    2014-05-01

    In many countries of the world, food demand exceeds the total agricultural production. In semi-arid countries, agricultural water demand often also exceeds the sustainable supply of water resources. These water-stressed countries are expected to become even drier, as a result of global climate change. This will have a significant impact on the future of the agricultural sector and on food security. The aim of the AGWATER project consortium is to provide recommendations for climate change adaptation for the agricultural sector in Cyprus and the wider Mediterranean region. Gridded climate data sets, with 1-km horizontal resolution were prepared for Cyprus for 1980-2010. Regional Climate Model results were statistically downscaled, with the help of spatial weather generators. A new soil map was prepared using a predictive modelling and mapping technique and a large spatial database with soil and environmental parameters. Stakeholder meetings with agriculture and water stakeholders were held to develop future water prices, based on energy scenarios and to identify climate resilient production systems. Green houses, including also hydroponic systems, grapes, potatoes, cactus pears and carob trees were the more frequently identified production systems. The green-blue-water model, based on the FAO-56 dual crop coefficient approach, has been set up to compute agricultural water demand and yields for all crop fields in Cyprus under selected future scenarios. A set of agricultural production and water use performance indicators are computed by the model, including green and blue water use, crop yield, crop water productivity, net value of crop production and economic water productivity. This work is part of the AGWATER project - AEIFORIA/GEOGRO/0311(BIE)/06 - co-financed by the European Regional Development Fund and the Republic of Cyprus through the Research Promotion Foundation.

  8. Troubling Muddy Waters: Problematizing Reflective Practice in Global Medical Education.

    Science.gov (United States)

    Naidu, Thirusha; Kumagai, Arno K

    2016-03-01

    The idea of exporting the concept of reflective practice for a global medical education audience is growing. However, the uncritical export and adoption of Western concepts of reflection may be inappropriate in non-Western societies. The emphasis in Western medical education on the use of reflection for a specific end--that is, the improvement of individual clinical practice--tends to ignore the range of reflective practice, concentrating on reflection alone while overlooking critical reflection and reflexivity. This Perspective places the concept of reflective practice under a critical lens to explore a broader view for its application in medical education outside the West. The authors suggest that ideas about reflection in medicine and medical education may not be as easily transferable from Western to non-Western contexts as concepts from biomedical science are. The authors pose the question, When "exporting" Western medical education strategies and principles, how often do Western-trained educators authentically open up to the possibility that there are alternative ways of seeing and knowing that may be valuable in educating Western physicians? One answer lies in the assertion that educators should aspire to turn exportation of educational theory into a truly bidirectional, collaborative exchange in which culturally conscious views of reflective practice contribute to humanistic, equitable patient care. This discussion engages in troubling the already-muddy waters of reflective practice by exploring the global applicability of reflective practice as it is currently applied in medical education. The globalization of medical education demands critical reflection on reflection itself.

  9. The global distribution of deep-water Antipatharia habitat

    Science.gov (United States)

    Yesson, Chris; Bedford, Faye; Rogers, Alex D.; Taylor, Michelle L.

    2017-11-01

    Antipatharia are a diverse group of corals with many species found in deep water. Many Antipatharia are habitat for associates, have extreme longevity and some species can occur beyond 8500 m depth. As they are major constituents of'coral gardens', which are Vulnerable Marine Ecosystems (VMEs), knowledge of their distribution and environmental requirements is an important pre-requisite for informed conservation planning particularly where the expense and difficulty of deep-sea sampling prohibits comprehensive surveys. This study uses a global database of Antipatharia distribution data to perform habitat suitability modelling using the Maxent methodology to estimate the global extent of black coral habitat suitability. The model of habitat suitability is driven by temperature but there is notable influence from other variables of topography, surface productivity and oxygen levels. This model can be used to predict areas of suitable habitat, which can be useful for conservation planning. The global distribution of Antipatharia habitat suitability shows a marked contrast with the distribution of specimen observations, indicating that many potentially suitable areas have not been sampled, and that sampling effort has been disproportionate to shallow, accessible areas inside marine protected areas (MPAs). Although 25% of Antipatharia observations are located in MPAs, only 7-8% of predicted suitable habitat is protected, which is short of the Convention on Biological Diversity target to protect 10% of ocean habitats by 2020.

  10. Water Stress Scatters Nitrogen Dilution Curves in Wheat

    Directory of Open Access Journals (Sweden)

    Marianne Hoogmoed

    2018-04-01

    Full Text Available Nitrogen dilution curves relate a crop’s critical nitrogen concentration (%Nc to biomass (W according to the allometric model %Nc = a W-b. This model has a strong theoretical foundation, and parameters a and b show little variation for well-watered crops. Here we explore the robustness of this model for water stressed crops. We established experiments to examine the combined effects of water stress, phenology, partitioning of biomass, and water-soluble carbohydrates (WSC, as driven by environment and variety, on the %Nc of wheat crops. We compared models where %Nc was plotted against biomass, growth stage and thermal time. The models were similarly scattered. Residuals of the %Nc - biomass model at anthesis were positively related to biomass, stem:biomass ratio, Δ13C and water supply, and negatively related to ear:biomass ratio and concentration of WSC. These are physiologically meaningful associations explaining the scatter of biomass-based dilution curves. Residuals of the thermal time model showed less consistent associations with these variables. The biomass dilution model developed for well-watered crops overestimates nitrogen deficiency of water-stressed crops, and a biomass-based model is conceptually more justified than developmental models. This has implications for diagnostic and modeling. As theory is lagging, a greater degree of empiricism might be useful to capture environmental, chiefly water, and genotype-dependent traits in the determination of critical nitrogen for diagnostic purposes. Sensitivity analysis would help to decide if scaling nitrogen dilution curves for crop water status, and genotype-dependent parameters are needed.

  11. Global transcriptomic profiling demonstrates induction of oxidative stress and of compensatory cellular stress responses in brown trout exposed to glyphosate and Roundup.

    Science.gov (United States)

    Uren Webster, Tamsyn M; Santos, Eduarda M

    2015-01-31

    Glyphosate, the active ingredient in Roundup formulations, is the most widely used herbicide worldwide, and as a result contaminates surface waters and has been detected in food residues, drinking water and human urine, raising concerns for potential environmental and human health impacts. Research has shown that glyphosate and Roundup can induce a broad range of biological effects in exposed organisms, particularly via generation of oxidative stress. However, there has been no comprehensive investigation of the global molecular mechanisms of toxicity of glyphosate and Roundup for any species. We aimed to characterise and compare the global mechanisms of toxicity of glyphosate and Roundup in the liver of brown trout (Salmo trutta), an ecologically and economically important vertebrate species, using RNA-seq on an Illumina HiSeq 2500 platform. To do this, we exposed juvenile female brown trout to 0, 0.01, 0.5 and 10 mg/L of glyphosate and Roundup (glyphosate acid equivalent) for 14 days, and sequenced 6 replicate liver samples from each treatment. We assembled the brown trout transcriptome using an optimised de novo approach, and subsequent differential expression analysis identified a total of 1020 differentially-regulated transcripts across all treatments. These included transcripts encoding components of the antioxidant system, a number of stress-response proteins and pro-apoptotic signalling molecules. Functional analysis also revealed over-representation of pathways involved in regulating of cell-proliferation and turnover, and up-regulation of energy metabolism and other metabolic processes. These transcriptional changes are consistent with generation of oxidative stress and the widespread induction of compensatory cellular stress response pathways. The mechanisms of toxicity identified were similar across both glyphosate and Roundup treatments, including for environmentally relevant concentrations. The significant alterations in transcript expression observed

  12. Stress-related factors in the emergence of transient global amnesia with hippocampal lesion

    Directory of Open Access Journals (Sweden)

    Juliane eDöhring

    2014-08-01

    Full Text Available The transient global amnesia (TGA is a rare amnesic syndrome that is characterized by an acute onset episode of an anterograde and retrograde amnesia. Its origin is still debated, but there is evidence for psychological factors involved in TGA. In neuroimaging, selective lesions in the CA1 fields of the hippocampus can be detected, a region that is particularly involved in the processing of memory, stress and emotion. The aim of this study was to assess the role of psychological stress in TGA by studying the prevalence of stress related precipitating events and individual stress-related personality profiles as well as coping strategies in patients. The hypothesis of a functional differentiation of the hippocampus in mnemonic and stress-related compartments was also evaluated. From all 113 patients, 18 % (n= 24 patients experienced emotional and psychological stress episodes directly before the TGA. In a cohort of 21 acute patients, TGA patients tend to cope with stress less efficiently and less constructively than controls. Patients who experienced a stress related precipitant event exhibited a higher level of anxiety in comparison to non-stress patients and controls. However, there was no difference between the general experience of stress and the number of stress inducing life events. The majority of patients (73% did show typical MRI lesions in the CA1 region of the hippocampal cornu ammonis. There was no clear association between stressful events, distribution of hippocampal CA1 lesions and behavioral patterns during the TGA. Disadvantageous coping strategies and an elevated anxiety level may increase the susceptibility to psychological stress which may facilitate the pathophysiological cascade in TGA. The findings suggest a role of emotional stress factors in the manifestation of TGA in a subgroup of patients. Stress may be one trigger involved in the emergence of transient lesions in the hippocampal CA1 region, which are thought to be the

  13. Daytime soybean transcriptome fluctuations during water deficit stress.

    Science.gov (United States)

    Rodrigues, Fabiana Aparecida; Fuganti-Pagliarini, Renata; Marcolino-Gomes, Juliana; Nakayama, Thiago Jonas; Molinari, Hugo Bruno Correa; Lobo, Francisco Pereira; Harmon, Frank G; Nepomuceno, Alexandre Lima

    2015-07-07

    Since drought can seriously affect plant growth and development and little is known about how the oscillations of gene expression during the drought stress-acclimation response in soybean is affected, we applied Illumina technology to sequence 36 cDNA libraries synthesized from control and drought-stressed soybean plants to verify the dynamic changes in gene expression during a 24-h time course. Cycling variables were measured from the expression data to determine the putative circadian rhythm regulation of gene expression. We identified 4866 genes differentially expressed in soybean plants in response to water deficit. Of these genes, 3715 were differentially expressed during the light period, from which approximately 9.55% were observed in both light and darkness. We found 887 genes that were either up- or down-regulated in different periods of the day. Of 54,175 predicted soybean genes, 35.52% exhibited expression oscillations in a 24 h period. This number increased to 39.23% when plants were submitted to water deficit. Major differences in gene expression were observed in the control plants from late day (ZT16) until predawn (ZT20) periods, indicating that gene expression oscillates during the course of 24 h in normal development. Under water deficit, dissimilarity increased in all time-periods, indicating that the applied stress influenced gene expression. Such differences in plants under stress were primarily observed in ZT0 (early morning) to ZT8 (late day) and also from ZT4 to ZT12. Stress-related pathways were triggered in response to water deficit primarily during midday, when more genes were up-regulated compared to early morning. Additionally, genes known to be involved in secondary metabolism and hormone signaling were also expressed in the dark period. Gene expression networks can be dynamically shaped to acclimate plant metabolism under environmental stressful conditions. We have identified putative cycling genes that are expressed in soybean leaves

  14. Proteomics Reveals Global Regulation of Protein SUMOylation by ATM and ATR Kinases during Replication Stress

    Directory of Open Access Journals (Sweden)

    Stephanie Munk

    2017-10-01

    Full Text Available The mechanisms that protect eukaryotic DNA during the cumbersome task of replication depend on the precise coordination of several post-translational modification (PTM-based signaling networks. Phosphorylation is a well-known regulator of the replication stress response, and recently an essential role for SUMOs (small ubiquitin-like modifiers has also been established. Here, we investigate the global interplay between phosphorylation and SUMOylation in response to replication stress. Using SUMO and phosphoproteomic technologies, we identify thousands of regulated modification sites. We find co-regulation of central DNA damage and replication stress responders, of which the ATR-activating factor TOPBP1 is the most highly regulated. Using pharmacological inhibition of the DNA damage response kinases ATR and ATM, we find that these factors regulate global protein SUMOylation in the protein networks that protect DNA upon replication stress and fork breakage, pointing to integration between phosphorylation and SUMOylation in the cellular systems that protect DNA integrity.

  15. Phosphatidic acid, a versatile water-stress signal in roots

    Directory of Open Access Journals (Sweden)

    Fionn eMcLoughlin

    2013-12-01

    Full Text Available Adequate water supply is of utmost importance for growth and reproduction of plants. In order to cope with water deprivation, plants have to adapt their development and metabolism to ensure survival. To maximize water use efficiency, plants use a large array of signaling mediators such as hormones, protein kinases and phosphatases, Ca2+, reactive oxygen species and low abundant phospholipids that together form complex signaling cascades. Phosphatidic acid (PA is a signaling lipid that rapidly accumulates in response to a wide array of abiotic stress stimuli. PA formation provides the cell with spatial and transient information about the external environment by acting as a protein-docking site in cellular membranes. PA reportedly binds to a number of proteins that play a role during water limiting conditions, such as drought and salinity and has been shown to play an important role in maintaining root system architecture. Members of two osmotic stress-activated protein kinase families, sucrose non-fermenting 1-related protein kinase 2 (SnRK2 and mitogen activated protein kinases (MAPKs were recently shown bind PA and are also involved in the maintenance of root system architecture and salinity stress tolerance. In addition, PA regulates several proteins involved in abscisic acid (ABA-signaling. PA-dependent recruitment of glyceraldehyde-3-phosphate dehydrogenase (GAPDH under water limiting conditions indicates a role in regulating metabolic processes. Finally, a recent study also shows the PA recruits the clathrin heavy chain and a potassium channel subunit, hinting towards additional roles in cellular trafficking and potassium homeostasis. Taken together, the rapidly increasing number of proteins reported to interact with PA implies a broad role for this versatile signaling phospholipid in mediating salt and water stress responses.

  16. Global Access to Safe Water: Accounting for Water Quality and the Resulting Impact on MDG Progress

    Directory of Open Access Journals (Sweden)

    Joe LoBuglio

    2012-03-01

    Full Text Available Monitoring of progress towards the Millennium Development Goal (MDG drinking water target relies on classification of water sources as “improved” or “unimproved” as an indicator for water safety. We adjust the current Joint Monitoring Programme (JMP estimate by accounting for microbial water quality and sanitary risk using the only-nationally representative water quality data currently available, that from the WHO and UNICEF “Rapid Assessment of Drinking Water Quality”. A principal components analysis (PCA of national environmental and development indicators was used to create models that predicted, for most countries, the proportions of piped and of other-improved water supplies that are faecally contaminated; and of these sources, the proportions that lack basic sanitary protection against contamination. We estimate that 1.8 billion people (28% of the global population used unsafe water in 2010. The 2010 JMP estimate is that 783 million people (11% use unimproved sources. Our estimates revise the 1990 baseline from 23% to 37%, and the target from 12% to 18%, resulting in a shortfall of 10% of the global population towards the MDG target in 2010. In contrast, using the indicator “use of an improved source” suggests that the MDG target for drinking-water has already been achieved. We estimate that an additional 1.2 billion (18% use water from sources or systems with significant sanitary risks. While our estimate is imprecise, the magnitude of the estimate and the health and development implications suggest that greater attention is needed to better understand and manage drinking water safety.

  17. Global Access to Safe Water: Accounting for Water Quality and the Resulting Impact on MDG Progress

    Science.gov (United States)

    Onda, Kyle; LoBuglio, Joe; Bartram, Jamie

    2012-01-01

    Monitoring of progress towards the Millennium Development Goal (MDG) drinking water target relies on classification of water sources as “improved” or “unimproved” as an indicator for water safety. We adjust the current Joint Monitoring Programme (JMP) estimate by accounting for microbial water quality and sanitary risk using the only-nationally representative water quality data currently available, that from the WHO and UNICEF “Rapid Assessment of Drinking Water Quality”. A principal components analysis (PCA) of national environmental and development indicators was used to create models that predicted, for most countries, the proportions of piped and of other-improved water supplies that are faecally contaminated; and of these sources, the proportions that lack basic sanitary protection against contamination. We estimate that 1.8 billion people (28% of the global population) used unsafe water in 2010. The 2010 JMP estimate is that 783 million people (11%) use unimproved sources. Our estimates revise the 1990 baseline from 23% to 37%, and the target from 12% to 18%, resulting in a shortfall of 10% of the global population towards the MDG target in 2010. In contrast, using the indicator “use of an improved source” suggests that the MDG target for drinking-water has already been achieved. We estimate that an additional 1.2 billion (18%) use water from sources or systems with significant sanitary risks. While our estimate is imprecise, the magnitude of the estimate and the health and development implications suggest that greater attention is needed to better understand and manage drinking water safety. PMID:22690170

  18. Proteomics Reveals Global Regulation of Protein SUMOylation by ATM and ATR Kinases during Replication Stress

    DEFF Research Database (Denmark)

    Munk, Stephanie; Sigurðsson, Jón Otti; Xiao, Zhenyu

    2017-01-01

    The mechanisms that protect eukaryotic DNA during the cumbersome task of replication depend on the precise coordination of several post-translational modification (PTM)-based signaling networks. Phosphorylation is a well-known regulator of the replication stress response, and recently an essentia....... They analyze changes in the SUMO and phosphoproteome after MMC and hydroxyurea treatments and find that the DNA damage response kinases ATR and ATM globally regulate SUMOylation upon replication stress and fork breakage....

  19. Corrosion and stress corrosion cracking in supercritical water

    Science.gov (United States)

    Was, G. S.; Ampornrat, P.; Gupta, G.; Teysseyre, S.; West, E. A.; Allen, T. R.; Sridharan, K.; Tan, L.; Chen, Y.; Ren, X.; Pister, C.

    2007-09-01

    Supercritical water (SCW) has attracted increasing attention since SCW boiler power plants were implemented to increase the efficiency of fossil-based power plants. The SCW reactor (SCWR) design has been selected as one of the Generation IV reactor concepts because of its higher thermal efficiency and plant simplification as compared to current light water reactors (LWRs). Reactor operating conditions call for a core coolant temperature between 280 °C and 620 °C at a pressure of 25 MPa and maximum expected neutron damage levels to any replaceable or permanent core component of 15 dpa (thermal reactor design) and 100 dpa (fast reactor design). Irradiation-induced changes in microstructure (swelling, radiation-induced segregation (RIS), hardening, phase stability) and mechanical properties (strength, thermal and irradiation-induced creep, fatigue) are also major concerns. Throughout the core, corrosion, stress corrosion cracking, and the effect of irradiation on these degradation modes are critical issues. This paper reviews the current understanding of the response of candidate materials for SCWR systems, focusing on the corrosion and stress corrosion cracking response, and highlights the design trade-offs associated with certain alloy systems. Ferritic-martensitic steels generally have the best resistance to stress corrosion cracking, but suffer from the worst oxidation. Austenitic stainless steels and Ni-base alloys have better oxidation resistance but are more susceptible to stress corrosion cracking. The promise of grain boundary engineering and surface modification in addressing corrosion and stress corrosion cracking performance is discussed.

  20. The effect of water on thermal stresses in polymer composites

    Science.gov (United States)

    Sullivan, Roy M.

    1994-01-01

    The fundamentals of the thermodynamic theory of mixtures and continuum thermochemistry are reviewed for a mixture of condensed water and polymer. A specific mixture which is mechanically elastic with temperature and water concentration gradients present is considered. An expression for the partial pressure of water in the mixture is obtained based on certain assumptions regarding the thermodynamic state of the water in the mixture. Along with a simple diffusion equation, this partial pressure expression may be used to simulate the thermostructural behavior of polymer composite materials due to water in the free volumes of the polymer. These equations are applied to a specific polymer composite material during isothermal heating conditions. The thermal stresses obtained by the application of the theory are compared to measured results to verify the accuracy of the approach.

  1. Transcriptome Dynamics of Pseudomonas putida KT2440 under Water Stress

    DEFF Research Database (Denmark)

    Gülez, Gamze; Dechesne, Arnaud; Workman, Christopher

    2012-01-01

    Water deprivation can be a major stressor to microbial life in surface and subsurface soil. In unsaturated soils, the matric potential (Ψm) is often the main component of the water potential, which measures the thermodynamic availability of water. A low matric potential usually translates...... into water forming thin liquid films in the soil pores. Little is known of how bacteria respond to such conditions, where, in addition to facing water deprivation that might impair their metabolism, they have to adapt their dispersal strategy as swimming motility may be compromised. Using the pressurized...... porous surface model (PPSM), which allows creation of thin liquid films by controlling Ψm, we examined the transcriptome dynamics of Pseudomonas putida KT2440. We identified the differentially expressed genes in cells exposed to a mild matric stress (–0.4 MPa) for 4, 24, or 72 h. The major response...

  2. Compounding Impacts of Human-Induced Water Stress and Climate Change on Water Availability

    Science.gov (United States)

    Mehran, Ali; AghaKouchak, Amir; Nakhjiri, Navid; Stewardson, Michael J.; Peel, Murray C.; Phillips, Thomas J.; Wada, Yoshihide; Ravalico, Jakin K.

    2017-01-01

    The terrestrial phase of the water cycle can be seriously impacted by water management and human water use behavior (e.g., reservoir operation, and irrigation withdrawals). Here we outline a method for assessing water availability in a changing climate, while explicitly considering anthropogenic water demand scenarios and water supply infrastructure designed to cope with climatic extremes. The framework brings a top-down and bottom-up approach to provide localized water assessment based on local water supply infrastructure and projected water demands. When our framework is applied to southeastern Australia we find that, for some combinations of climatic change and water demand, the region could experience water stress similar or worse than the epic Millennium Drought. We show considering only the influence of future climate on water supply, and neglecting future changes in water demand and water storage augmentation might lead to opposing perspectives on future water availability. While human water use can significantly exacerbate climate change impacts on water availability, if managed well, it allows societies to react and adapt to a changing climate. The methodology we present offers a unique avenue for linking climatic and hydrologic processes to water resource supply and demand management and other human interactions.

  3. Moderate water stress affects tomato leaf water relations in dependence on the nitrogen supply

    NARCIS (Netherlands)

    Garcia, A.L.; Marcelis, L.F.M.; Garcia-Sanchez, F.; Nicolas, N.; Martinez, V.

    2007-01-01

    The responses of water relations, stomatal conductance (g(s)) and growth parameters of tomato (Lycopersicon esculentum Mill. cv. Royesta) plants to nitrogen fertilisation and drought were studied. The plants were subjected to a long-term, moderate and progressive water stress by adding 80 % of the

  4. Placental oxidative stress and decreased global DNA methylation are corrected by copper in the Cohen diabetic rat

    Energy Technology Data Exchange (ETDEWEB)

    Ergaz, Zivanit, E-mail: zivanit@hadassah.org.il [Hebrew University Hadassah Medical School, Jerusalem (Israel); Guillemin, Claire [Department of Pharmacology and Therapeutics, McGill University, Montreal (Canada); Neeman-azulay, Meytal; Weinstein-Fudim, Liza [Hebrew University Hadassah Medical School, Jerusalem (Israel); Stodgell, Christopher J.; Miller, Richard K. [Department of Obstetrics and Gynecology, University of Rochester, Rochester (United States); Szyf, Moshe [Department of Pharmacology and Therapeutics, McGill University, Montreal (Canada); Ornoy, Asher [Hebrew University Hadassah Medical School, Jerusalem (Israel)

    2014-05-01

    Fetal Growth Restriction (FGR) is a leading cause for long term morbidity. The Cohen diabetic sensitive rats (CDs), originating from Wistar, develop overt diabetes when fed high sucrose low copper diet (HSD) while the original outbred Sabra strain do not. HSD induced FGR and fetal oxidative stress, more prominent in the CDs, that was alleviated more effectively by copper than by the anti-oxidant vitamins C and E. Our aim was to evaluate the impact of copper or the anti-oxidant Tempol on placental size, protein content, oxidative stress, apoptosis and total DNA methylation. Animals were mated following one month of HSD or regular chow diet and supplemented throughout pregnancy with either 0, 1 or 2 ppm of copper sulfate or Tempol in their drinking water. Placental weight on the 21st day of pregnancy decreased in dams fed HSD and improved upon copper supplementation. Placental/fetal weight ratio increased among the CDs. Protein content decreased in Sabra but increased in CDs fed HSD. Oxidative stress biochemical markers improved upon copper supplementation; immunohistochemistry for oxidative stress markers was similar between strains and diets. Caspase 3 was positive in more placentae of dams fed HSD than those fed RD. Placental global DNA methylation was decreased only among the CDs dams fed HSD. We conclude that FGR in this model is associated with smaller placentae, reduced DNA placental methylation, and increased oxidative stress that normalized with copper supplementation. DNA hypomethylation makes our model a unique method for investigating genes associated with growth, oxidative stress, hypoxia and copper. - Highlights: • Sensitive Cohen diabetic rats (CDs) had small placentae and growth restricted fetuses. • CDs dams fed high sucrose low copper diet had placental global DNA hypomethylation. • Caspase 3 was positive in more placentae of dams fed HSD than those fed RD. • Oxidative stress parameters improved by Tempol and resolved by copper

  5. Placental oxidative stress and decreased global DNA methylation are corrected by copper in the Cohen diabetic rat

    International Nuclear Information System (INIS)

    Ergaz, Zivanit; Guillemin, Claire; Neeman-azulay, Meytal; Weinstein-Fudim, Liza; Stodgell, Christopher J.; Miller, Richard K.; Szyf, Moshe; Ornoy, Asher

    2014-01-01

    Fetal Growth Restriction (FGR) is a leading cause for long term morbidity. The Cohen diabetic sensitive rats (CDs), originating from Wistar, develop overt diabetes when fed high sucrose low copper diet (HSD) while the original outbred Sabra strain do not. HSD induced FGR and fetal oxidative stress, more prominent in the CDs, that was alleviated more effectively by copper than by the anti-oxidant vitamins C and E. Our aim was to evaluate the impact of copper or the anti-oxidant Tempol on placental size, protein content, oxidative stress, apoptosis and total DNA methylation. Animals were mated following one month of HSD or regular chow diet and supplemented throughout pregnancy with either 0, 1 or 2 ppm of copper sulfate or Tempol in their drinking water. Placental weight on the 21st day of pregnancy decreased in dams fed HSD and improved upon copper supplementation. Placental/fetal weight ratio increased among the CDs. Protein content decreased in Sabra but increased in CDs fed HSD. Oxidative stress biochemical markers improved upon copper supplementation; immunohistochemistry for oxidative stress markers was similar between strains and diets. Caspase 3 was positive in more placentae of dams fed HSD than those fed RD. Placental global DNA methylation was decreased only among the CDs dams fed HSD. We conclude that FGR in this model is associated with smaller placentae, reduced DNA placental methylation, and increased oxidative stress that normalized with copper supplementation. DNA hypomethylation makes our model a unique method for investigating genes associated with growth, oxidative stress, hypoxia and copper. - Highlights: • Sensitive Cohen diabetic rats (CDs) had small placentae and growth restricted fetuses. • CDs dams fed high sucrose low copper diet had placental global DNA hypomethylation. • Caspase 3 was positive in more placentae of dams fed HSD than those fed RD. • Oxidative stress parameters improved by Tempol and resolved by copper

  6. Improving Water Resources Management on Global and Region Scales - Evaluating Strategies for Water Futures with the IIASA's Community Water Model

    Science.gov (United States)

    Burek, P.; Kahil, T.; Satoh, Y.; Greve, P.; Byers, E.; Langan, S.; Wada, Y.

    2017-12-01

    Half of the planet's population is severely impacted by severe water issues including absent or unreliable water supply, sanitation, poor water quality, unmitigated floods and droughts, and degraded water environments. In recent years, global water security has been highlighted not only by the science community but also by business leaders as one of the greatest threats to sustainable human development for different generations. How can we ensure the well-being of people and ecosystems with limited water, technology and financial resources? To evaluate this, IIASA's Water Futures and Solutions Initiative (WFaS) is identifying a portfolios of robust and cost-effective options across different economic sectors including agriculture, energy, manufacturing, households, and environment and ecosystems. Options to increase water supply and accessibility are evaluated together with water demand management and water governance options. To test these solution-portfolios in order to obtain a clear picture of the opportunities but also of the risks and the trade-offs we have developed the Community Water Model (CWATM) which joins IIASA's integrated assessment modeling framework, coupling hydrology with hydro-economics (ECHO model), energy (MESSAGE model) and land use (GLOBIOM model). CWATM has been developed to work flexibly with varying spatial resolutions from global to regional levels. The model is open source and community-driven to promote our work amongst the wider water and other science community worldwide, with flexibility to link to other models and integrate newly developed modules such as water quality. In order to identify the solution portfolios, we present a global hotspots assessment of water-related risks with the ability to zoom in at regional scale using the example of the Lake Victoria basin in E. Africa. We show how socio-economic and climate change will alter spatial patterns of the hydrological cycle and have regional impacts on water availability. At

  7. Gas exchanges and water use efficiency in the selection of tomato genotypes tolerant to water stress.

    Science.gov (United States)

    Borba, M E A; Maciel, G M; Fraga Júnior, E F; Machado Júnior, C S; Marquez, G R; Silva, I G; Almeida, R S

    2017-06-20

    Water stress can affect the yield in tomato crops and, despite this, there are few types of research aiming to select tomato genotypes resistant to the water stress using physiological parameters. This experiment aimed to study the variables that are related to the gas exchanges and the efficiency in water use, in the selection of tomato genotypes tolerant to water stress. It was done in a greenhouse, measuring 7 x 21 m, in a randomized complete block design, with four replications (blocks), being five genotypes in the F 2 BC 1 generation, which were previously obtained from an interspecific cross between Solanum pennellii versus S. lycopersicum and three check treatments, two susceptible [UFU-22 (pre-commercial line) and cultivar Santa Clara] and one resistant (S. pennellii). At the beginning of flowering, the plants were submitted to a water stress condition, through irrigation suspension. After that CO 2 assimilation, internal CO 2 , stomatal conductance, transpiration, leaf temperature, instantaneous water use efficiency, intrinsic efficiency of water use, instantaneous carboxylation efficiency, chlorophyll a and b, and the potential leaf water (Ψf) were observed. Almost all variables that were analyzed, except CO 2 assimilation and instantaneous carboxylation efficiency, demonstrated the superiority of the wild accession, S. pennellii, concerning the susceptible check treatments. The high photosynthetic rate and the low stomatal conductance and transpiration, presented by the UFU22/F 2 BC 1 #2 population, allowed a better water use efficiency. Because of that, these physiological characteristics are promising in the selection of tomato genotypes tolerant to water stress.

  8. Diffuse radiation increases global ecosystem-level water-use efficiency

    Science.gov (United States)

    Moffat, A. M.; Reichstein, M.; Cescatti, A.; Knohl, A.; Zaehle, S.

    2012-12-01

    Current environmental changes lead not only to rising atmospheric CO2 levels and air temperature but also to changes in air pollution and thus the light quality of the solar radiation reaching the land-surface. While rising CO2 levels are thought to enhance photosynthesis and closure of stomata, thus leading to relative water savings, the effect of diffuse radiation on transpiration by plants is less clear. It has been speculated that the stimulation of photosynthesis by increased levels of diffuse light may be counteracted by higher transpiration and consequently water depletion and drought stress. Ultimately, in water co-limited systems, the overall effect of diffuse radiation will depend on the sensitivity of canopy transpiration versus photosynthesis to diffuse light, i.e. whether water-use efficiency changes with relative levels of diffuse light. Our study shows that water-use efficiency increases significantly with higher fractions of diffuse light. It uses the ecosystem-atmosphere gas-exchange observations obtained with the eddy covariance method at 29 flux tower sites. In contrast to previous global studies, the analysis is based directly on measurements of diffuse radiation. Its effect on water-use efficiency was derived by analyzing the multivariate response of carbon and water fluxes to radiation and air humidity using a purely empirical approach based on artificial neural networks. We infer that per unit change of diffuse fraction the water-use efficiency increases up to 40% depending on diffuse fraction levels and ecosystem type. Hence, in regions with increasing diffuse radiation positive effects on primary production are expected even under conditions where water is co-limiting productivity.

  9. Establishing and testing a catchment water footprint framework to inform sustainable irrigation water use for an aquifer under stress.

    Science.gov (United States)

    le Roux, Betsie; van der Laan, Michael; Vahrmeijer, Teunis; Bristow, Keith L; Annandale, John G

    2017-12-01

    Future water scarcities in the face of an increasing population, climate change and the unsustainable use of aquifers will present major challenges to global food production. The ability of water footprints (WFs) to inform water resource management at catchment-scale was investigated on the Steenkoppies Aquifer, South Africa. Yields based on cropping areas were multiplied with season-specific WFs for each crop to determine blue and green water consumption by agriculture. Precipitation and evapotranspiration of natural vegetation and other uses of blue water were included with the agricultural WFs to compare water availability and consumption in a catchment sustainability assessment. This information was used to derive a water balance and develop a catchment WF framework that gave important insights into the hydrology of the aquifer through a simplified method. This method, which requires the monitoring of only a few key variables, including rainfall, agricultural production, WFs of natural vegetation and other blue water flows, can be applied to inform the sustainability of catchment scale water use (as opposed to more complex hydrological studies). Results indicate that current irrigation on the Steenkoppies Aquifer is unsustainable. This is confirmed by declining groundwater levels, and suggests that there should be no further expansion of irrigated agriculture on the Steenkoppies Aquifer. Discrepancies between in- and outflows of water in the catchment indicated that further development of the WF approach is required to improve understanding of the geohydrology of the aquifer and to set and meet sustainability targets for the aquifer. It is envisaged that this 'working' framework can be applied to other water-stressed aquifers around the world. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  10. Solar-Induced Fluorescence of Maize Across A Water Stress Gradient in the Midwestern USA

    Science.gov (United States)

    Miao, G.; Guan, K.; Suyker, A.; Yang, X.; Benarcchi, C. J.; Gamon, J. A.; Berry, J. A.; DeLucia, E.; Franz, T.; Arkebauer, T. J.; Zygielbaum, A. I.; Walter-Shea, E. A.; Moore, C.; Zhang, Y.; Kim, H.; Hmimina, G.

    2017-12-01

    In the coming decades, agricultural ecosystems will be challenged by rising temperatures, changing rainfall patterns, and increasing extreme weather. Understanding how crops respond to weather variability and how humans manage agriculture to mitigate and adapt to climate change is critical for improving agricultural sustainability and supporting increasing global food demands. Accurately estimating gross primary productivity (GPP) of crops is of importance to evaluate their sustainability and capability but remains a challenge. The recent development of solar-induced fluorescence (SIF) technology is stimulating studies to use SIF to approximate GPP. It has been observed that agricultural lands have remarkably high SIF and the SIF signal could be used as an indicator of vegetation stress, which is particularly valuable for improved monitoring of crop productivity and stress. To investigate the applicability of SIF for detecting maize stress and estimating GPP, we deployed three FluoSpec2 systems in 2017 at three long-term eddy covariance flux sites across the US Corn Belt, a rain-fed maize field (AmeriFlux sites US-NE3) and an irrigated maize field (US-NE2) at Mead, Nebraska and a rain-fed maize field at Urbana, Illinois. Together these form a water stress gradient. Variations in GPP, SIF, photosynthetic efficiency (LUE), SIF yield (SIFy), and relationships between GPP and SIF, LUE and SIFy will be compared as indications of the difference in maize growth across the water stress gradient. More importantly, differences in GPP and SIF signals will be examined over multiple growth stages to assess the potential of SIF in identifying the growth stages that are mostly affected by water stress and the ones that play the most important roles on the crop yield.

  11. Stress Coefficients for Soil Water Balance Combined with Water Stress Indicators for Irrigation Scheduling of Woody Crops

    Directory of Open Access Journals (Sweden)

    Maria Isabel Ferreira

    2017-06-01

    Full Text Available There are several causes for the failure of empirical models to estimate soil water depletion and to calculate irrigation depths, and the problem is particularly critical in tall, uneven, deficit irrigated (DI crops in Mediterranean climates. Locally measured indicators that quantify water status are useful for addressing those causes and providing feed-back information for improving the adequacy of simple models. Because of their high aerodynamic resistance, the canopy conductance of woody crops is an important factor in determining evapotranspiration (ET, and accurate stress coefficient (Ks values are needed to quantify the impact of stomatal closure on ET. A brief overview of basic general principles for irrigation scheduling is presented with emphasis on DI applications that require Ks modelling. The limitations of existing technology related to scheduling of woody crops are discussed, including the shortcomings of plant-based approaches. In relation to soil water deficit and/or predawn leaf water potential, several woody crop Ks functions are presented in a secondary analysis. Whenever the total and readily available water data were available, a simple Ks model was tested. The ultimate aim of this discussion is to illustrate the central concept: that a combination of simple ET models and water stress indicators is required for scheduling irrigation of deep-rooted woody crops.

  12. Towards Estimating Water Stress through Leaf and Canopy Water Content Derived from Optical and Thermal Hyperspectral Data

    Science.gov (United States)

    Corbin, Amie; Timmermans, Joris; van der Tol, Christiaan; Verhoef, Wout

    2015-04-01

    A competition for available (drinkable) water has arisen. This competition originated due to increasing global population and the respective needs of this population. The water demand for human consumption and irrigation of food producing crops and biofuel related vegetation, has led to early indication of drought as a key issue in many studies. However, while drought monitoring systems might provide some reasonable predictions, at the time of visible symptoms of plant stress, a plant may already be critically affected. Consequently, pre-symptomatic non-destructive monitoring of plants is needed. In many studies of plant stress, this is performed by examining internal plant physiology through existing remote sensing techniques, with varying applications. However, a uniform remote sensing method for identifying early plant stress under drought conditions is still developing. In some instances, observations of vegetation water content are used to assess the impact of soil water deficit on the health of a plant or canopy. When considering water content as an indicator of water stress in a plant, this comments not only on the condition of the plant itself, but also provides indicators of photosynthetic activity and the susceptibility to drought. Several indices of canopy health currently exists (NDVI, DVI, SAVI, etc.) using optical and near infrared reflectance bands. However, these are considered inadequate for vegetation health investigations because such semi-empirical models result in less accuracy for canopy measurements. In response, a large amount of research has been conducted to estimate canopy health directly from considering the full spectral behaviour. In these studies , the canopy reflectance has been coupled to leaf parameters, by using coupling leaf radiative transfer models (RTM), such as PROSPECT, to a canopy RTM such as SAIL. The major shortcomings of these researches is that they have been conducted primarily for optical remote sensing. Recently

  13. Drinking water biofilm cohesiveness changes under chlorination or hydrodynamic stress.

    Science.gov (United States)

    Mathieu, L; Bertrand, I; Abe, Y; Angel, E; Block, J C; Skali-Lami, S; Francius, G

    2014-05-15

    Attempts at removal of drinking water biofilms rely on various preventive and curative strategies such as nutrient reduction in drinking water, disinfection or water flushing, which have demonstrated limited efficiency. The main reason for these failures is the cohesiveness of the biofilm driven by the physico-chemical properties of its exopolymeric matrix (EPS). Effective cleaning procedures should break up the matrix and/or change the elastic properties of bacterial biofilms. The aim of this study was to evaluate the change in the cohesive strength of two-month-old drinking water biofilms under increasing hydrodynamic shear stress τw (from ∼0.2 to ∼10 Pa) and shock chlorination (applied concentration at T0: 10 mg Cl2/L; 60 min contact time). Biofilm erosion (cell loss per unit surface area) and cohesiveness (changes in the detachment shear stress and cluster volumes measured by atomic force microscopy (AFM)) were studied. When rapidly increasing the hydrodynamic constraint, biofilm removal was found to be dependent on a dual process of erosion and coalescence of the biofilm clusters. Indeed, 56% of the biofilm cells were removed with, concomitantly, a decrease in the number of the 50-300 μm(3) clusters and an increase in the number of the smaller (i.e., 600 μm(3)) ones. Moreover, AFM evidenced the strengthening of the biofilm structure along with the doubling of the number of contact points, NC, per cluster volume unit following the hydrodynamic disturbance. This suggests that the compactness of the biofilm exopolymers increases with hydrodynamic stress. Shock chlorination removed cells (-75%) from the biofilm while reducing the volume of biofilm clusters. Oxidation stress resulted in a decrease in the cohesive strength profile of the remaining drinking water biofilms linked to a reduction in the number of contact points within the biofilm network structure in particular for the largest biofilm cluster volumes (>200 μm(3)). Changes in the cohesive

  14. Global monthly water scarcity: Blue water footprints versus blue water availability

    NARCIS (Netherlands)

    Hoekstra, Arjen Ysbert; Mekonnen, Mesfin; Chapagain, Ashok; Mathews, R.E.; Richter, B.D.

    2012-01-01

    Freshwater scarcity is a growing concern, placing considerable importance on the accuracy of indicators used to characterize and map water scarcity worldwide. We improve upon past efforts by using estimates of blue water footprints (consumptive use of ground- and surface water flows) rather than

  15. Effects of virtual water flow on regional water resources stress: A case study of grain in China.

    Science.gov (United States)

    Sun, Shikun; Wang, Yubao; Engel, Bernie A; Wu, Pute

    2016-04-15

    Scarcity of water resources is one of the major challenges in the world, particularly for the main water consumer, agriculture. Virtual water flow (VWF) promotes water redistribution geographically and provides a new solution for resolving regional water shortage and improving water use efficiency in the world. Virtual water transfer among regions will have a significant influence on the water systems in both grain export and import regions. In order to assess the impacts of VWF related grain transfer on regional water resources conditions, the study takes mainland China as study area for a comprehensive evaluation of virtual water flow on regional water resources stress. Results show that Northeast China and Huang-Huai-Hai region are the major grain production regions as well as the major virtual water export regions. National water savings related to grain VWF was about 58Gm(3), with 48Gm(3) blue water and 10Gm(3) green water. VWF changes the original water distribution and has a significant effect on water resources in both virtual water import and export regions. Grain VWF significantly increased water stress in grain export regions and alleviated water stress in grain import regions. Water stress index (WSI) of Heilongjiang and Inner Mongolia has been increased by 138% and 129% due to grain export. Stress from water shortages is generally severe in export regions, and issues with the sustainability of grain production and VWF pattern are worthy of further exploration. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. 76 FR 55060 - Aquatic Ecosystems, Water Quality, and Global Change: Challenges of Conducting Multi-Stressor...

    Science.gov (United States)

    2011-09-06

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9459-7] Aquatic Ecosystems, Water Quality, and Global Change... entitled, Aquatic Ecosystems, Water Quality, and Global Change: Challenges of Conducting Multi- stressor... vulnerability of water quality and aquatic ecosystems across the United States to the potential impacts of...

  17. Global life satisfaction predicts ambulatory affect, stress, and cortisol in daily life in working adults.

    Science.gov (United States)

    Smyth, Joshua M; Zawadzki, Matthew J; Juth, Vanessa; Sciamanna, Christopher N

    2017-04-01

    Global life satisfaction has been linked with long-term health advantages, yet how life satisfaction impacts the trajectory of long-term health is unclear. This paper examines one such possible mechanism-that greater life satisfaction confers momentary benefits in daily life that accumulate over time. A community sample of working adults (n = 115) completed a measure of life satisfaction and then three subsequent days of ecological momentary assessment surveys (6 times/day) measuring affect (i.e., emotional valence, arousal), and perceived stress, and also provided salivary cortisol samples. Multilevel models indicated that people with higher (vs. lower) levels of life satisfaction reported better momentary affect, less stress, marginally lower momentary levels and significantly altered diurnal slopes of cortisol. Findings suggest individuals with high global life satisfaction have advantageous daily experiences, providing initial evidence for potential mechanisms through which global life satisfaction may help explain long-term health benefits.

  18. Global assessment of water policy vulnerability under uncertainty in water scarcity projections

    Science.gov (United States)

    Greve, Peter; Kahil, Taher; Satoh, Yusuke; Burek, Peter; Fischer, Günther; Tramberend, Sylvia; Byers, Edward; Flörke, Martina; Eisner, Stephanie; Hanasaki, Naota; Langan, Simon; Wada, Yoshihide

    2017-04-01

    Water scarcity is a critical environmental issue worldwide, which has been driven by the significant increase in water extractions during the last century. In the coming decades, climate change is projected to further exacerbate water scarcity conditions in many regions around the world. At present, one important question for policy debate is the identification of water policy interventions that could address the mounting water scarcity problems. Main interventions include investing in water storage infrastructures, water transfer canals, efficient irrigation systems, and desalination plants, among many others. This type of interventions involve long-term planning, long-lived investments and some irreversibility in choices which can shape development of countries for decades. Making decisions on these water infrastructures requires anticipating the long term environmental conditions, needs and constraints under which they will function. This brings large uncertainty in the decision-making process, for instance from demographic or economic projections. But today, climate change is bringing another layer of uncertainty that make decisions even more complex. In this study, we assess in a probabilistic approach the uncertainty in global water scarcity projections following different socioeconomic pathways (SSPs) and climate scenarios (RCPs) within the first half of the 21st century. By utilizing an ensemble of 45 future water scarcity projections based on (i) three state-of-the-art global hydrological models (PCR-GLOBWB, H08, and WaterGAP), (ii) five climate models, and (iii) three water scenarios, we have assessed changes in water scarcity and the associated uncertainty distribution worldwide. The water scenarios used here are developed by IIASA's Water Futures and Solutions (WFaS) Initiative. The main objective of this study is to improve the contribution of hydro-climatic information to effective policymaking by identifying spatial and temporal policy

  19. Inverse estimation of soil hydraulic properties and water repellency following artificially induced drought stress

    Directory of Open Access Journals (Sweden)

    Filipović Vilim

    2018-06-01

    Full Text Available Global climate change is projected to continue and result in prolonged and more intense droughts, which can increase soil water repellency (SWR. To be able to estimate the consequences of SWR on vadose zone hydrology, it is important to determine soil hydraulic properties (SHP. Sequential modeling using HYDRUS (2D/3D was performed on an experimental field site with artificially imposed drought scenarios (moderately M and severely S stressed and a control plot. First, inverse modeling was performed for SHP estimation based on water and ethanol infiltration experimental data, followed by model validation on one selected irrigation event. Finally, hillslope modeling was performed to assess water balance for 2014. Results suggest that prolonged dry periods can increase soil water repellency. Inverse modeling was successfully performed for infiltrating liquids, water and ethanol, with R2 and model efficiency (E values both > 0.9. SHP derived from the ethanol measurements showed large differences in van Genuchten-Mualem (VGM parameters for the M and S plots compared to water infiltration experiments. SWR resulted in large saturated hydraulic conductivity (Ks decrease on the M and S scenarios. After validation of SHP on water content measurements during a selected irrigation event, one year simulations (2014 showed that water repellency increases surface runoff in non-structured soils at hillslopes.

  20. Global crop yield response to extreme heat stress under multiple climate change futures

    Science.gov (United States)

    Deryng, D.; Conway, D.; Ramankutty, N.; Price, J.; Warren, R.

    2014-12-01

    Extreme heat stress during the crop reproductive period can be critical for crop productivity. Projected changes in the frequency and severity of extreme climatic events are expected to negatively impact crop yields and global food production. This study applies the global crop model PEGASUS to quantify, for the first time at the global scale, impacts of extreme heat stress on maize, spring wheat and soybean yields resulting from 72 climate change scenarios for the 21st century. Our results project maize to face progressively worse impacts under a range of RCPs but spring wheat and soybean to improve globally through to the 2080s due to CO2 fertilization effects, even though parts of the tropic and sub-tropic regions could face substantial yield declines. We find extreme heat stress at anthesis (HSA) by the 2080s (relative to the 1980s) under RCP 8.5, taking into account CO2 fertilization effects, could double global losses of maize yield (dY = -12.8 ± 6.7% versus -7.0 ± 5.3% without HSA), reduce projected gains in spring wheat yield by half (dY = 34.3 ± 13.5% versus 72.0 ± 10.9% without HSA) and in soybean yield by a quarter (dY = 15.3 ± 26.5% versus 20.4 ± 22.1% without HSA). The range reflects uncertainty due to differences between climate model scenarios; soybean exhibits both positive and negative impacts, maize is generally negative and spring wheat generally positive. Furthermore, when assuming CO2 fertilization effects to be negligible, we observe drastic climate mitigation policy as in RCP 2.6 could avoid more than 80% of the global average yield losses otherwise expected by the 2080s under RCP 8.5. We show large disparities in climate impacts across regions and find extreme heat stress adversely affects major producing regions and lower income countries.

  1. Water stress and harmful insects in agri-forest ecosystems

    Directory of Open Access Journals (Sweden)

    Mario Solinas

    2010-09-01

    Full Text Available Present knowledge on ecological services supplied by insects to natural terrestrial ecosystems, allow us to identify many homeostatic mechanisms regulating biological balance as well as life perpetuation of the said ecosystems; at the same time, that knowledge represents a sound referring point to understanding how those mechanisms do work so as to manage them in the anthropized ecosystems (i.e., agriculture and forests, and especially in order to identify in the latter the natural meaning of the so called insect outbreaks, so as to forecast and possibly prevent them; as well as, when needed, to conceive and formulate efficient control strategies having minimal environmental impact. Water factor is crucial with genesis, configuration and conservation of a terrestrial ecosystem (both natural or anthropized as a whole or in its individual components, but especially concerning plant life as well as plant interactions with phytophagous invertebrates, mainly insects. Insect-plant trophic interactions are principally influenced by the water conditions in the ecosystem, and the impact of phytophagous insects on crops is markedly affected. Extremely severe water stress, especially if prolonged, prevent insect life just like plant’s life but a moderate and not so prolonged water stress, while depressing plant vigour, paradoxically can improve development and multiplication of phytophagous arthropods, with severe consequences on woody plants especially, and forest trees markedly.

  2. Water stress and harmful insects in agri-forest ecosystems

    Directory of Open Access Journals (Sweden)

    Mario Solinas

    2011-02-01

    Full Text Available Present knowledge on ecological services supplied by insects to natural terrestrial ecosystems, allow us to identify many homeostatic mechanisms regulating biological balance as well as life perpetuation of the said ecosystems; at the same time, that knowledge represents a sound referring point to understanding how those mechanisms do work so as to manage them in the anthropized ecosystems (i.e., agriculture and forests, and especially in order to identify in the latter the natural meaning of the so called insect outbreaks, so as to forecast and possibly prevent them; as well as, when needed, to conceive and formulate efficient control strategies having minimal environmental impact. Water factor is crucial with genesis, configuration and conservation of a terrestrial ecosystem (both natural or anthropized as a whole or in its individual components, but especially concerning plant life as well as plant interactions with phytophagous invertebrates, mainly insects. Insect-plant trophic interactions are principally influenced by the water conditions in the ecosystem, and the impact of phytophagous insects on crops is markedly affected. Extremely severe water stress, especially if prolonged, prevent insect life just like plant’s life but a moderate and not so prolonged water stress, while depressing plant vigour, paradoxically can improve development and multiplication of phytophagous arthropods, with severe consequences on woody plants especially, and forest trees markedly.

  3. Water stress and harmful insects in agri-forest ecosystems

    Directory of Open Access Journals (Sweden)

    Mario Solinas

    Full Text Available Present knowledge on ecological services supplied by insects to natural terrestrial ecosystems, allow us to identify many homeostatic mechanisms regulating biological balance as well as life perpetuation of the said ecosystems; at the same time, that knowledge represents a sound referring point to understanding how those mechanisms do work so as to manage them in the anthropized ecosystems (i.e., agriculture and forests, and especially in order to identify in the latter the natural meaning of the so called insect outbreaks, so as to forecast and possibly prevent them; as well as, when needed, to conceive and formulate efficient control strategies having minimal environmental impact. Water factor is crucial with genesis, configuration and conservation of a terrestrial ecosystem (both natural or anthropized as a whole or in its individual components, but especially concerning plant life as well as plant interactions with phytophagous invertebrates, mainly insects. Insect-plant trophic interactions are principally influenced by the water conditions in the ecosystem, and the impact of phytophagous insects on crops is markedly affected. Extremely severe water stress, especially if prolonged, prevent insect life just like plant’s life but a moderate and not so prolonged water stress, while depressing plant vigour, paradoxically can improve development and multiplication of phytophagous arthropods, with severe consequences on woody plants especially, and forest trees markedly.

  4. NONLINEAR EVOLUTION OF GLOBAL HYDRODYNAMIC SHALLOW-WATER INSTABILITY IN THE SOLAR TACHOCLINE

    International Nuclear Information System (INIS)

    Dikpati, Mausumi

    2012-01-01

    We present a fully nonlinear hydrodynamic 'shallow-water' model of the solar tachocline. The model consists of a global spherical shell of differentially rotating fluid, which has a deformable top, thus allowing motions in radial directions along with latitudinal and longitudinal directions. When the system is perturbed, in the course of its nonlinear evolution it can generate unstable low-frequency shallow-water shear modes from the differential rotation, high-frequency gravity waves, and their interactions. Radiative and overshoot tachoclines are characterized in this model by high and low effective gravity values, respectively. Building a semi-implicit spectral scheme containing very low numerical diffusion, we perform nonlinear evolution of shallow-water modes. Our first results show that (1) high-latitude jets or polar spin-up occurs due to nonlinear evolution of unstable hydrodynamic shallow-water disturbances and differential rotation, (2) Reynolds stresses in the disturbances together with changing shell thickness and meridional flow are responsible for the evolution of differential rotation, (3) disturbance energy primarily remains concentrated in the lowest longitudinal wavenumbers, (4) an oscillation in energy between perturbed and unperturbed states occurs due to evolution of these modes in a nearly dissipation-free system, and (5) disturbances are geostrophic, but occasional nonadjustment in geostrophic balance can occur, particularly in the case of high effective gravity, leading to generation of gravity waves. We also find that a linearly stable differential rotation profile remains nonlinearly stable.

  5. Global DNA methylation and oxidative stress biomarkers in workers exposed to metal oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Liou, Saou-Hsing; Wu, Wei-Te; Liao, Hui-Yi [National Institute of Environmental Health Sciences, National Health Research Institutes, Zhunan, Miaoli County, Taiwan (China); Chen, Chao-Yu; Tsai, Cheng-Yen; Jung, Wei-Ting [Department of Chemistry, Fu Jen Catholic University, New Taipei City, Taiwan (China); Lee, Hui-Ling, E-mail: huilinglee3573@gmail.com [Department of Chemistry, Fu Jen Catholic University, New Taipei City, Taiwan (China)

    2017-06-05

    Highlights: • Global methylation and oxidative DNA damage levels in nanomaterial handling workers were assessed. • 8-isoprostane in exhaled breath condensate of workers exposed to nanoparticles was higher. • 8-OHdG was negatively correlated with global methylation. • Exposure to metal oxide nanoparticles may lead to global methylation and DNA oxidative damage. - Abstract: This is the first study to assess global methylation, oxidative DNA damage, and lipid peroxidation in workers with occupational exposure to metal oxide nanomaterials (NMs). Urinary and white blood cell (WBC) 8-hydroxydeoxyguanosine (8-OHdG), and exhaled breath condensate (EBC) 8-isoprostane were measured as oxidative stress biomarkers. WBC global methylation was measured as an epigenetic alteration. Exposure to TiO{sub 2}, SiO{sub 2,} and indium tin oxide (ITO) resulted in significantly higher oxidative biomarkers such as urinary 8-OHdG and EBC 8-isoprostane. However, significantly higher WBC 8-OHdG and lower global methylation were only observed in ITO handling workers. Significant positive correlations were noted between WBC and urinary 8-OHdG (Spearman correlation r = 0.256, p = 0.003). Furthermore, a significant negative correlation was found between WBC 8-OHdG and global methylation (r = −0.272, p = 0.002). These results suggest that exposure to metal oxide NMs may lead to global methylation, DNA oxidative damage, and lipid peroxidation.

  6. TRMM and Its Connection to the Global Water Cycle

    Science.gov (United States)

    Kummerow, Christian; Hong, Ye

    1999-01-01

    The importance of quantitative knowledge of tropical rainfall, its associated latent heating and variability is summarized in the context of the global hydrologic cycle. Much of the tropics is covered by oceans. What land exists, is covered largely by rainforests that are only thinly populated. The only way to adequately measure the global tropical rainfall for climate and general circulation models is from space. The TRMM orbit is inclined 35' leading to good sampling in the tropics and a rapid precession to study the diurnal cycle of precipitation. The precipitation instrument complement consists of the first rain radar to be flown in space (PR), a multi-channel passive microwave sensor (TMI) and a five-channel VIS/IR (VIRS) sensor. The precipitation radar operates at a frequency of 13.6 GHz. The swath width is 220 km, with a horizontal resolution of 4 km and the vertical resolution of 250 in. The minimum detectable signal from the precipitation radar has been measured at 17 dBZ. The TMI instrument is designed similar to the SSM/I with two important changes. The 22.235 GHz water vapor absorption channel of the SSM/I was moved to 21.3 GHz in order to avoid saturation in the tropics and 10.7 GHz V&H polarized channels were added to expand the dynamic range of rainfall estimates. The resolution of the TMI varies from 4.6 km at 85 GHz to 36 km at 10.7 GHz. The visible and infrared sensor (VIRS) measures radiation at 0.63, 1.6, 3.75, 10.8 and 12.0 microns. The spatial resolution of all five VIRS channels is 2 km at nadir. In addition to the three primary rainfall instruments, TRMM will also carry a Lightning Imaging Sensor (LIS) and a Clouds and the Earth's Radiant Energy System (CERES) instrument.

  7. Global monthly water scarcity: blue water footprints versus blue water availability.

    Science.gov (United States)

    Hoekstra, Arjen Y; Mekonnen, Mesfin M; Chapagain, Ashok K; Mathews, Ruth E; Richter, Brian D

    2012-01-01

    Freshwater scarcity is a growing concern, placing considerable importance on the accuracy of indicators used to characterize and map water scarcity worldwide. We improve upon past efforts by using estimates of blue water footprints (consumptive use of ground- and surface water flows) rather than water withdrawals, accounting for the flows needed to sustain critical ecological functions and by considering monthly rather than annual values. We analyzed 405 river basins for the period 1996-2005. In 201 basins with 2.67 billion inhabitants there was severe water scarcity during at least one month of the year. The ecological and economic consequences of increasing degrees of water scarcity--as evidenced by the Rio Grande (Rio Bravo), Indus, and Murray-Darling River Basins--can include complete desiccation during dry seasons, decimation of aquatic biodiversity, and substantial economic disruption.

  8. Global Stress Classification System for Materials Used in Solar Energy Applications

    Science.gov (United States)

    Slamova, Karolina; Schill, Christian; Herrmann, Jan; Datta, Pawan; Chih Wang, Chien

    2016-08-01

    Depending on the geographical location, the individual or combined impact of environmental stress factors and corresponding performance losses for solar applications varies significantly. Therefore, as a strategy to reduce investment risks and operating and maintenance costs, it is necessary to adapt the materials and components of solar energy systems specifically to regional environmental conditions. The project «GloBe Solar» supports this strategy by focusing on the development of a global stress classification system for materials in solar energy applications. The aim of this classification system is to assist in the identification of the individual stress conditions for every location on the earth's surface. The stress classification system could serve as a decision support tool for the industry (manufacturers, investors, lenders and project developers) and help to improve knowledge and services that can provide higher confidence to solar power systems.

  9. Will building new reservoirs always help increase the water supply reliability? - insight from a modeling-based global study

    Science.gov (United States)

    Zhuang, Y.; Tian, F.; Yigzaw, W.; Hejazi, M. I.; Li, H. Y.; Turner, S. W. D.; Vernon, C. R.

    2017-12-01

    More and more reservoirs are being build or planned in order to help meet the increasing water demand all over the world. However, is building new reservoirs always helpful to water supply? To address this question, the river routing module of Global Change Assessment Model (GCAM) has been extended with a simple yet physical-based reservoir scheme accounting for irrigation, flood control and hydropower operations at each individual reservoir. The new GCAM river routing model has been applied over the global domain with the runoff inputs from the Variable Infiltration Capacity Model. The simulated streamflow is validated at 150 global river basins where the observed streamflow data are available. The model performance has been significantly improved at 77 basins and worsened at 35 basins. To facilitate the analysis of additional reservoir storage impacts at the basin level, a lumped version of GCAM reservoir model has been developed, representing a single lumped reservoir at each river basin which has the regulation capacity of all reservoir combined. A Sequent Peak Analysis is used to estimate how much additional reservoir storage is required to satisfy the current water demand. For basins with water deficit, the water supply reliability can be improved with additional storage. However, there is a threshold storage value at each basin beyond which the reliability stops increasing, suggesting that building new reservoirs will not help better relieve the water stress. Findings in the research can be helpful to the future planning and management of new reservoirs.

  10. Analysis of the Citrullus colocynthis transcriptome during water deficit stress.

    Directory of Open Access Journals (Sweden)

    Zhuoyu Wang

    Full Text Available Citrullus colocynthis is a very drought tolerant species, closely related to watermelon (C. lanatus var. lanatus, an economically important cucurbit crop. Drought is a threat to plant growth and development, and the discovery of drought inducible genes with various functions is of great importance. We used high throughput mRNA Illumina sequencing technology and bioinformatic strategies to analyze the C. colocynthis leaf transcriptome under drought treatment. Leaf samples at four different time points (0, 24, 36, or 48 hours of withholding water were used for RNA extraction and Illumina sequencing. qRT-PCR of several drought responsive genes was performed to confirm the accuracy of RNA sequencing. Leaf transcriptome analysis provided the first glimpse of the drought responsive transcriptome of this unique cucurbit species. A total of 5038 full-length cDNAs were detected, with 2545 genes showing significant changes during drought stress. Principle component analysis indicated that drought was the major contributing factor regulating transcriptome changes. Up regulation of many transcription factors, stress signaling factors, detoxification genes, and genes involved in phytohormone signaling and citrulline metabolism occurred under the water deficit conditions. The C. colocynthis transcriptome data highlight the activation of a large set of drought related genes in this species, thus providing a valuable resource for future functional analysis of candidate genes in defense of drought stress.

  11. Global land and water grabbing for food and bioenergy

    Science.gov (United States)

    Rulli, M. C.; D'Odorico, P.

    2014-12-01

    The increasing demand for food, fibers and biofuels, the consequently escalating prices of agricultural products, and the uncertainty of international food markets have recently drawn the attention of governments and corporations toward investments in productive agricultural land, mostly in developing countries. Since 2000 more than 37 million hectares of arable land have been purchased or leased by foreign investors worldwide. The targeted regions are typically located in areas where crop yields are relatively low because of lack of modern technology. It is expected that in the long run large scale investments in agriculture and the consequent development of commercial farming will bring the technology required to close the existing crop yield gaps. Recently, a number of studies and reports have documented the process of foreign land acquisition, while the associated appropriation of land based resources (e.g., water and crops) has remained poorly investigated. The amount of food this land can produce and the number of people it could feed still needs to be quantified. It is also unclear to what extent the acquired land will be used to for biofuel production and the role played by U.S. and E.U. bioenergy policies as drivers of the ongoing land rush. The environmental impacts of these investments in agriculture require adequate investigation. Here we provide a global quantitative assessment of the rates of water and crop appropriation potentially associated with large scale land acquisitions. We evaluate the associated impacts on the food and energy security of both target and investors' countries, and highlight the societal and environmental implications of the land rush phenomenon.

  12. Assessment of the terrestrial water balance using the global water availability and use model WaterGAP - status and challenges

    Science.gov (United States)

    Müller Schmied, Hannes; Döll, Petra

    2017-04-01

    The estimation of the World's water resources has a long tradition and numerous methods for quantification exists. The resulting numbers vary significantly, leaving room for improvement. Since some decades, global hydrological models (GHMs) are being used for large scale water budget assessments. GHMs are designed to represent the macro-scale hydrological processes and many of those models include human water management, e.g. irrigation or reservoir operation, making them currently the first choice for global scale assessments of the terrestrial water balance within the Anthropocene. The Water - Global Assessment and Prognosis (WaterGAP) is a model framework that comprises both the natural and human water dimension and is in development and application since the 1990s. In recent years, efforts were made to assess the sensitivity of water balance components to alternative climate forcing input data and, e.g., how this sensitivity is affected by WaterGAP's calibration scheme. This presentation shows the current best estimate of terrestrial water balance components as simulated with WaterGAP by 1) assessing global and continental water balance components for the climate period 1971-2000 and the IPCC reference period 1986-2005 for the most current WaterGAP version using a homogenized climate forcing data, 2) investigating variations of water balance components for a number of state-of-the-art climate forcing data and 3) discussing the benefit of the calibration approach for a better observation-data constrained global water budget. For the most current WaterGAP version 2.2b and a homogenized combination of the two WATCH Forcing Datasets, global scale (excluding Antarctica and Greenland) river discharge into oceans and inland sinks (Q) is assessed to be 40 000 km3 yr-1 for 1971-2000 and 39 200 km3 yr-1 for 1986-2005. Actual evapotranspiration (AET) is close to each other with around 70 600 (70 700) km3 yr-1 as well as water consumption with 1000 (1100) km3 yr-1. The

  13. Managing aquatic ecosystems and water resources under multiple stress--an introduction to the MARS project.

    Science.gov (United States)

    Hering, Daniel; Carvalho, Laurence; Argillier, Christine; Beklioglu, Meryem; Borja, Angel; Cardoso, Ana Cristina; Duel, Harm; Ferreira, Teresa; Globevnik, Lidija; Hanganu, Jenica; Hellsten, Seppo; Jeppesen, Erik; Kodeš, Vit; Solheim, Anne Lyche; Nõges, Tiina; Ormerod, Steve; Panagopoulos, Yiannis; Schmutz, Stefan; Venohr, Markus; Birk, Sebastian

    2015-01-15

    Water resources globally are affected by a complex mixture of stressors resulting from a range of drivers, including urban and agricultural land use, hydropower generation and climate change. Understanding how stressors interfere and impact upon ecological status and ecosystem services is essential for developing effective River Basin Management Plans and shaping future environmental policy. This paper details the nature of these problems for Europe's water resources and the need to find solutions at a range of spatial scales. In terms of the latter, we describe the aims and approaches of the EU-funded project MARS (Managing Aquatic ecosystems and water Resources under multiple Stress) and the conceptual and analytical framework that it is adopting to provide this knowledge, understanding and tools needed to address multiple stressors. MARS is operating at three scales: At the water body scale, the mechanistic understanding of stressor interactions and their impact upon water resources, ecological status and ecosystem services will be examined through multi-factorial experiments and the analysis of long time-series. At the river basin scale, modelling and empirical approaches will be adopted to characterise relationships between multiple stressors and ecological responses, functions, services and water resources. The effects of future land use and mitigation scenarios in 16 European river basins will be assessed. At the European scale, large-scale spatial analysis will be carried out to identify the relationships amongst stress intensity, ecological status and service provision, with a special focus on large transboundary rivers, lakes and fish. The project will support managers and policy makers in the practical implementation of the Water Framework Directive (WFD), of related legislation and of the Blueprint to Safeguard Europe's Water Resources by advising the 3rd River Basin Management Planning cycle, the revision of the WFD and by developing new tools for

  14. Species as Stressors: Heterospecific Interactions and the Cellular Stress Response under Global Change.

    Science.gov (United States)

    Gunderson, Alex R; King, Emily E; Boyer, Kirsten; Tsukimura, Brian; Stillman, Jonathon H

    2017-07-01

    Anthropogenic global change is predicted to increase the physiological stress of organisms through changes in abiotic conditions such as temperature, pH, and pollution. However, organisms can also experience physiological stress through interactions with other species, especially parasites, predators, and competitors. The stress of species interactions could be an important driver of species' responses to global change as the composition of biological communities change through factors such as distributional and phenological shifts. Interactions between biotic and abiotic stressors could also induce non-linear physiological stress responses under global change. One of the primary means by which organisms deal with physiological stress is through the cellular stress response (CSR), which is broadly the upregulation of a conserved set of genes that facilitate the removal and repair of damaged macromolecules. Here, we present data on behavioral interactions and CSR gene expression for two competing species of intertidal zone porcelain crab (Petrolisthes cinctipes and Petrolisthes manimaculis). We found that P. cinctipes and P. manimaculis engage in more agonistic behaviors when interacting with heterospecifics than conspecifics; however, we found no evidence that heterospecific interactions induced a CSR in these species. In addition to our new data, we review the literature with respect to CSR induction via species interactions, focusing on predator-prey systems and heterospecific competition. We find extensive evidence for predators to induce cellular stress and aspects of the CSR in prey, even in the absence of direct physical contact between species. Effects of heterospecific competition on the CSR have been studied far less, but we do find evidence that agonistic interactions with heterospecifics can induce components of the CSR. Across all published studies, there is clear evidence that species interactions can lead to cellular stress and induction of the CSR

  15. Passionate Perspectives: Global Change Emersion in Southwestern Dust and Waters

    Science.gov (United States)

    Byrne, J. M.; Little, L. J.

    2014-12-01

    "Tell me, and I'll forget. Show me, and I may remember. But involve me, and I'll understand" (attributed to various philosophers). How many professors have shared 20-30 days traveling, hiking, camping, and Coleman stove cooking with 25-50 young adults? Sixteen times! Way over a year on a field trip…holy sh*t! Tired… but happy. We have offered an extended camping field trip that feature the highlands and deserts of Utah, Arizona, Mexico and California; with side trips to Colorado and New Mexico. Two science and one social science courses focus on global environmental change, water and human development. The discussion will center on the short and long term evolution(s) that have occurred: who, what, where, when and why, and perhaps most important, HOW! These tours are amazing learning experiences that go way beyond any classroom. Many of our students have found the expedition to be life changing - or life awakening. Hopefully we can squeeze the essence into our few minutes of fame :) "Once more I am roaring drunk with the lust of life and adventure and unbearable beauty... Adventure seems to beset me on all quarters without my even searching for it... Though not all my days are as wild as this, each one holds its surprises, and I have seen almost more beauty than I can bear." - Everett Reuss

  16. Ground-Based Global Positioning System (GPS) Meteorology Integrated Precipitable Water Vapor (IPW)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ground-Based Global Positioning System (GPS) Meteorology Integrated Precipitable Water Vapor (IPW) data set measures atmospheric water vapor using ground-based...

  17. The Impact Of Climate Change On Water Resources: Global And ...

    African Journals Online (AJOL)

    GHGs) is increasing and this has resulted to changing global climate with increasing temperature. The rise in global average temperatures since 1860 now exceeds 0.6OC. The effect of the GHGs concentration on global warming as at 2100 is ...

  18. Temporal versus spatial variation in leaf reflectance under changing water stress conditions

    Science.gov (United States)

    Cohen, Warren B.

    1991-01-01

    Leaf reflectance changes associated with changes in water stress were analyzed in two separate experiments. Results indicate that the variation in reflectance among collections of leaves of a given species all at the same level of water stress is at least as great as the variation in reflectance associated with changes in water stress for a given leaf collection of that species. The implications is that results from leaf reflectance-water stress studies have only limited applicability to the remote sensing of plant canopy water stress.

  19. Abscisic acid biosynthesis in water-stressed leaves

    International Nuclear Information System (INIS)

    Li, Yi.

    1989-01-01

    Although abscisic acid (ABA) was discovered 30 years ago, very little is known about its biosynthetic pathway in higher plants. Two hypotheses have been proposed: (i) a direct pathway involving only C-15 intermediates like farnesyl pyrophosphate, (ii) an indirect pathway involving C-40 intermediates like the xanthophylls. When 14 CO 2 was fed into greened bean plants, the 14 C specific activity of ABA was always lower than those in xanthophylls, such as violaxanthin and lutein, regardless of 12 CO 2 chase periods. The ABA accumulation in green leaves was not affected by fluridone when plants were stressed once, but the 14 C incorporation into ABA was inhibited to the same extent as those of xanthophylls. The incorporation of 18 O into the ABA ring when violaxanthin was labeled by 18 O in vivo via the violaxanthin cycle indicates that at least a portion of ABA was derived from 18 O-labeled violaxanthin during water stress

  20. An assessment of global warming stress on Caribbean coral reef ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, D.K.; Hendec, J.C.; Mendez, A. (NOAA, Miami, FL (USA). Atlantic Oceanography and Meteorology Laboratory)

    1992-07-01

    There is evidence that stress on coral reef ecosystems in the Caribbean region is increasing. Recently numerous authors have stated that the major stress results from 'abnormally high' seasonal sea surface temperatures (SST) and have implicated global warming as a cause, stating that recent episodes of coral bleaching result therefrom. However, an analysis of available SST data sets shows no discernible warming trend that could cause an increase in coral bleaching. Given the lack of long-term records synoptic with observations of coral ecosystem health, there is insufficient evidence available to label temperatures observed in coincidence with recent regional bleaching events as 'abnormally' high.

  1. An assessment of global warming stress on Caribbean coral reef ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, D K; Hendec, J C; Mendez, A [NOAA, Miami, FL (USA). Atlantic Oceanography and Meteorology Laboratory

    1992-07-01

    There is evidence that stress on coral reef ecosystems in the Caribbean region is increasing. Recently numerous authors have stated that the major stress results from 'abnormally high' seasonal sea surface temperatures (SST) and have implicated global warming as a cause, stating that recent episodes of coral bleaching result therefrom. However, an analysis of available SST data sets shows no discernible warming trend that could cause an increase in coral bleaching. Given the lack of long-term records synoptic with observations of coral ecosystem health, there is insufficient evidence available to label temperatures observed in coincidence with recent regional bleaching events as 'abnormally' high.

  2. Wheat yield loss attributable to heat waves, drought and water excess at the global, national and subnational scales

    Science.gov (United States)

    Zampieri, M.; Ceglar, A.; Dentener, F.; Toreti, A.

    2017-06-01

    Heat waves and drought are often considered the most damaging climatic stressors for wheat. In this study, we characterize and attribute the effects of these climate extremes on wheat yield anomalies (at global and national scales) from 1980 to 2010. Using a combination of up-to-date heat wave and drought indexes (the latter capturing both excessively dry and wet conditions), we have developed a composite indicator that is able to capture the spatio-temporal characteristics of the underlying physical processes in the different agro-climatic regions of the world. At the global level, our diagnostic explains a significant portion (more than 40%) of the inter-annual production variability. By quantifying the contribution of national yield anomalies to global fluctuations, we have found that just two concurrent yield anomalies affecting the larger producers of the world could be responsible for more than half of the global annual fluctuations. The relative importance of heat stress and drought in determining the yield anomalies depends on the region. Moreover, in contrast to common perception, water excess affects wheat production more than drought in several countries. We have also performed the same analysis at the subnational level for France, which is the largest wheat producer of the European Union, and home to a range of climatic zones. Large subnational variability of inter-annual wheat yield is mostly captured by the heat and water stress indicators, consistently with the country-level result.

  3. Cowpea bean production under water stress using hydrogels

    Directory of Open Access Journals (Sweden)

    Marília Barcelos Souza Lopes

    2017-03-01

    Full Text Available The population increase and the need of intensifying food production, coupled with the scarcity of water resources, have led to the search of alternatives that reduce consumption and optimize the water use during cultivation. In this context, hydrogels become a strategy in agricultural management, due to their water retention capacity in the soil and availability to plants. This study aimed at evaluating the efficiency of hydrogels on the development and production of cowpea bean ('Sempre-verde' cultivar under water stress, in a greenhouse. The experiment was performed in a randomized block design, with five replications, in a 4 x 5 factorial scheme, consisting of four types of hydrogel (Hydroplan-EB HyA, with granulometry of 1-3 mm; Hydroplan-EB HyB, with granulometry of 0.5-1 mm; Hydroplan-EB HyC, with granulometry < 0.5 mm; Polim-Agri, with granulometry of 1-0.5 mm and five concentrations (0 g pot-1; 1.5 g pot-1; 3 g pot-1; 4.5 g pot-1; 6 g pot-1. The following traits were evaluated: number of pods per plant, number of grains per pod and grain yield. The highest concentration (6 g pot-1 resulted in a higher number of pods and yield for all the hydrogels, especially for HyC and Polim-Agro, which presented 7.4 pods plant-1 and 7.0 pods plant-1, with yield of 15.43 g plant-1 and 16.68 g plant-1, respectively. The use of hydrogel shows to be efficient for reducing yield losses under water stress.

  4. Crop coefficient, yield response to water stress and water productivity of teff (Eragrostis tef (Zucc.)

    NARCIS (Netherlands)

    Araya, A.; Stroosnijder, L.; Girmay, G.; Keesstra, S.D.

    2011-01-01

    In the semi-arid region of Tigray, Northen Ethiopia a two season experiment was conducted to measure evapotranspiration, estimate yield response to water stress and derive the crop coefficient of teff using the single crop coefficient approach with simple, locally made lysimeters and field plots.

  5. Physiological responses of selected African sorghum landraces to progressive water stress and re-watering

    CSIR Research Space (South Africa)

    Devnarain, N

    2016-03-01

    Full Text Available stress treatments and a moderate re-watered treatment on day 7. Plant height, soil moisture, and LWC were measured during harvests. Chlorophyll, carotenoid, and proline contents were quantified. All five genotypes maintained LWC above 80% during mild...

  6. Quantifying the Global Fresh Water Budget: Capabilities from Current and Future Satellite Sensors

    Science.gov (United States)

    Hildebrand, Peter; Zaitchik, Benjamin

    2007-01-01

    The global water cycle is complex and its components are difficult to measure, particularly at the global scales and with the precision needed for assessing climate impacts. Recent advances in satellite observational capabilities, however, are greatly improving our knowledge of the key terms in the fresh water flux budget. Many components of the of the global water budget, e.g. precipitation, atmospheric moisture profiles, soil moisture, snow cover, sea ice are now routinely measured globally using instruments on satellites such as TRMM, AQUA, TERRA, GRACE, and ICESat, as well as on operational satellites. New techniques, many using data assimilation approaches, are providing pathways toward measuring snow water equivalent, evapotranspiration, ground water, ice mass, as well as improving the measurement quality for other components of the global water budget. This paper evaluates these current and developing satellite capabilities to observe the global fresh water budget, then looks forward to evaluate the potential for improvements that may result from future space missions as detailed by the US Decadal Survey, and operational plans. Based on these analyses, and on the goal of improved knowledge of the global fresh water budget under the effects of climate change, we suggest some priorities for the future, based on new approaches that may provide the improved measurements and the analyses needed to understand and observe the potential speed-up of the global water cycle under the effects of climate change.

  7. Global Reprogramming of Transcription in Chinese Fir (Cunninghamia lanceolata during Progressive Drought Stress and after Rewatering

    Directory of Open Access Journals (Sweden)

    Ruiyang Hu

    2015-07-01

    Full Text Available Chinese fir (Cunninghamia lanceolata, an evergreen conifer, is the most commonly grown afforestation species in southeast China due to its rapid growth and good wood qualities. To gain a better understanding of the drought-signalling pathway and the molecular metabolic reactions involved in the drought response, we performed a genome-wide transcription analysis using RNA sequence data. In this study, Chinese fir plantlets were subjected to progressively prolonged drought stress, up to 15 d, followed by rewatering under controlled environmental conditions. Based on observed morphological changes, plantlets experienced mild, moderate, or severe water stress before rehydration. Transcriptome analysis of plantlets, representing control and mild, moderate, and severe drought-stress treatments, and the rewatered plantlets, identified several thousand genes whose expression was altered in response to drought stress. Many genes whose expression was tightly coupled to the levels of drought stress were identified, suggesting involvement in Chinese fir drought adaptation responses. These genes were associated with transcription factors, signal transport, stress kinases, phytohormone signalling, and defence/stress response. The present study provides the most comprehensive transcriptome resource and the first dynamic transcriptome profiles of Chinese fir under drought stress. The drought-responsive genes identified in this study could provide further information for understanding the mechanisms of drought tolerance in Chinese fir.

  8. Integrated assessment of global water scarcity over the 21st century - Part 2: Climate change mitigation policies

    Science.gov (United States)

    Hejazi, M. I.; Edmonds, J.; Clarke, L.; Kyle, P.; Davies, E.; Chaturvedi, V.; Eom, J.; Wise, M.; Patel, P.; Calvin, K.

    2013-03-01

    We investigate the effects of emission mitigation policies on water scarcity both globally and regionally using the Global Change Assessment Model (GCAM), a leading community integrated assessment model of energy, agriculture, climate, and water. Three climate policy scenarios with increasing mitigation stringency of 7.7, 5.5, and 4.2 W m-2 in year 2095 (equivalent to the SRES A2, B2, and B1 emission scenarios, respectively), under two carbon tax regimes (a universal carbon tax (UCT) which includes land use change emissions, and a fossil fuel and industrial emissions carbon tax (FFICT) which excludes land use change emissions) are analyzed. The results are compared to a baseline scenario (i.e. no climate change mitigation policy) with radiative forcing reaching 8.8 W m-2 (equivalent to the SRES A1Fi emission scenario) by 2095. When compared to the baseline scenario and maintaining the same baseline socioeconomic assumptions, water scarcity declines under a UCT mitigation policy but increases with a FFICT mitigation scenario by the year 2095 particularly with more stringent climate mitigation targets. The decreasing trend with UCT policy stringency is due to substitution from more water-intensive to less water-intensive choices in food and energy production, and in land use. Under the FFICT scenario, water scarcity is projected to increase driven by higher water demands for bio-energy crops. This study implies an increasingly prominent role for water availability in future human decisions, and highlights the importance of including water in integrated assessment of global change. Future research will be directed at incorporating water shortage feedbacks in GCAM to better understand how such stresses will propagate across the various human and natural systems in GCAM.

  9. eWaterCycle: A high resolution global hydrological model

    Science.gov (United States)

    van de Giesen, Nick; Bierkens, Marc; Drost, Niels; Hut, Rolf; Sutanudjaja, Edwin

    2014-05-01

    In 2013, the eWaterCycle project was started, which has the ambitious goal to run a high resolution global hydrological model. Starting point was the PCR-GLOBWB built by Utrecht University. The software behind this model will partially be re-engineered in order to enable to run it in a High Performance Computing (HPC) environment. The aim is to have a spatial resolution of 1km x 1km. The idea is also to run the model in real-time and forecasting mode, using data assimilation. An on-demand hydraulic model will be available for detailed flow and flood forecasting in support of navigation and disaster management. The project faces a set of scientific challenges. First, to enable the model to run in a HPC environment, model runs were analyzed to examine on which parts of the program most CPU time was spent. These parts were re-coded in Open MPI to allow for parallel processing. Different parallelization strategies are thinkable. In our case, it was decided to use watershed logic as a first step to distribute the analysis. There is rather limited recent experience with HPC in hydrology and there is much to be learned and adjusted, both on the hydrological modeling side and the computer science side. For example, an interesting early observation was that hydrological models are, due to their localized parameterization, much more memory intensive than models of sister-disciplines such as meteorology and oceanography. Because it would be deadly to have to swap information between CPU and hard drive, memory management becomes crucial. A standard Ensemble Kalman Filter (enKF) would, for example, have excessive memory demands. To circumvent these problems, an alternative to the enKF was developed that produces equivalent results. This presentation shows the most recent results from the model, including a 5km x 5km simulation and a proof of concept for the new data assimilation approach. Finally, some early ideas about financial sustainability of an operational global

  10. Age differences in emotional responses to daily stress: the role of timing, severity, and global perceived stress.

    Science.gov (United States)

    Scott, Stacey B; Sliwinski, Martin J; Blanchard-Fields, Fredda

    2013-12-01

    Research on age differences in emotional responses to daily stress has produced inconsistent findings. Guided by recent theoretical advances in aging theory (S. T. Charles, 2010, Strength and vulnerability integration: A model of emotional well-being across adulthood, Psychological Bulletin, Vol. 136, pp. 1068-1091) that emphasize the importance of context for predicting when and how age is related to affective well-being, the current study examined age differences in emotional responses to everyday stressors. The present study examined how three contextual features (e.g., timing of exposure, stressor severity, global perceived stress [GPS]) moderate age differences in emotional experience in an ecological momentary assessment study of adults (N = 190) aged 18-81 years. Results indicated that older adults' negative affect (NA) was less affected by exposure to recent stressors than younger adults, but that there were no age differences in the effects of stressor exposure 3-6 hr afterward. Higher levels of GPS predicted amplified NA responses to daily stress, and controlling for GPS eliminated age differences in NA responses to stressors. No age differences in NA responses as a function of stressor severity were observed. In contrast, older age was associated with less of a decrease in PA when exposed to recent stressors or with more severe recent stressors. There were no age differences in the effect of previous stressor exposure or severity on PA, or any interactions between momentary or previous stress and GPS on PA. Together, these results support the notion that chronic stress plays a central role in emotional experience in daily life. We discuss the implications of these results for emotion theories of aging. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  11. Communicating the deadly consequences of global warming for human heat stress

    Science.gov (United States)

    Matthews, Tom K. R.; Wilby, Robert L.; Murphy, Conor

    2017-04-01

    In December of 2015, the international community pledged to limit global warming to below 2 °C above preindustrial (PI) to prevent dangerous climate change. However, to what extent, and for whom, is danger avoided if this ambitious target is realized? We address these questions by scrutinizing heat stress, because the frequency of extremely hot weather is expected to continue to rise in the approach to the 2 °C limit. We use analogs and the extreme South Asian heat of 2015 as a focusing event to help interpret the increasing frequency of deadly heat under specified amounts of global warming. Using a large ensemble of climate models, our results confirm that global mean air temperature is nonlinearly related to heat stress, meaning that the same future warming as realized to date could trigger larger increases in societal impacts than historically experienced. This nonlinearity is higher for heat stress metrics that integrate the effect of rising humidity. We show that, even in a climate held to 2 °C above PI, Karachi (Pakistan) and Kolkata (India) could expect conditions equivalent to their deadly 2015 heatwaves every year. With only 1.5 °C of global warming, twice as many megacities (such as Lagos, Nigeria, and Shanghai, China) could become heat stressed, exposing more than 350 million more people to deadly heat by 2050 under a midrange population growth scenario. The results underscore that, even if the Paris targets are realized, there could still be a significant adaptation imperative for vulnerable urban populations.

  12. Communicating the deadly consequences of global warming for human heat stress.

    Science.gov (United States)

    Matthews, Tom K R; Wilby, Robert L; Murphy, Conor

    2017-04-11

    In December of 2015, the international community pledged to limit global warming to below 2 °C above preindustrial (PI) to prevent dangerous climate change. However, to what extent, and for whom, is danger avoided if this ambitious target is realized? We address these questions by scrutinizing heat stress, because the frequency of extremely hot weather is expected to continue to rise in the approach to the 2 °C limit. We use analogs and the extreme South Asian heat of 2015 as a focusing event to help interpret the increasing frequency of deadly heat under specified amounts of global warming. Using a large ensemble of climate models, our results confirm that global mean air temperature is nonlinearly related to heat stress, meaning that the same future warming as realized to date could trigger larger increases in societal impacts than historically experienced. This nonlinearity is higher for heat stress metrics that integrate the effect of rising humidity. We show that, even in a climate held to 2 °C above PI, Karachi (Pakistan) and Kolkata (India) could expect conditions equivalent to their deadly 2015 heatwaves every year. With only 1.5 °C of global warming, twice as many megacities (such as Lagos, Nigeria, and Shanghai, China) could become heat stressed, exposing more than 350 million more people to deadly heat by 2050 under a midrange population growth scenario. The results underscore that, even if the Paris targets are realized, there could still be a significant adaptation imperative for vulnerable urban populations.

  13. Water resources conservation and nitrogen pollution reduction under global food trade and agricultural intensification

    NARCIS (Netherlands)

    Liu, Wenfeng; Yang, Hong; Liu, Yu; Kummu, Matti; Hoekstra, Arjen Y.; Liu, Junguo; Schulin, Rainer

    2018-01-01

    Global food trade entails virtual flows of agricultural resources and pollution across countries. Here we performed a global-scale assessment of impacts of international food trade on blue water use, total water use, and nitrogen (N) inputs and on N losses in maize, rice, and wheat production. We

  14. Hydrological impacts of global land cover change and human water use

    NARCIS (Netherlands)

    Bosmans, J.H.C.; van Beek, L.P.H.; Sutanudjaja, E.H.; Bierkens, M.F.P.

    2017-01-01

    Human impacts on global terrestrial hydrology have been accelerating during the 20th century. These human impacts include the effects of reservoir building and human water use, as well as land cover change. To date, many global studies have focussed on human water use, but only a few focus on or

  15. Development of a global Agricultural Stress Index System (ASIS) based on remote sensing data

    Science.gov (United States)

    Van Hoolst, R.

    2016-12-01

    According to the 2012 IPCC SREX report, extreme drought events are projected to become more frequent and intense in several regions of the world. Wide and timely monitoring systems are required to mitigate the impact of agricultural drought. Therefore, FAO's Global Information and Early Warning System (GIEWS) and the Climate, Energy and Tenure Division (NRC) have established the `Agricultural Stress Index System' (ASIS). The ASIS is a remote sensing application that provides early warnings of agricultural drought at a global scale. The ASIS has first been designed and described by Rojas et al. (2011). This study focused on the African continent and was based on the back processing of low resolution data of the NOAA-satellites. In the current setup, developed by VITO (Flemish Institute for Technological Research), the system operates in Near Real Time using data from the METOP-AVHRR sensor. The Agricultural Stress Index (ASI) is the percentage of agricultural area affected by drought in the course of the growing season within a given administrative unit. The start and end of the growing season are derived per pixel from the long term NDVI average of SPOT-VEGETATION. The Global Administrative Unit Layer (GAUL) defines the administrative boundaries at level 0, 1 and 2. A global cropland and grassland map eliminates non-agricultural areas. Temperature and NDVI anomalies are used as drought indicators and calculated at a per pixel base. The ASIS aggregates this information and produces every dekad global maps to highlight hotspots of drought stress. New developments are ongoing to strengthen the ASIS to produce country specific outputs, improve existing drought indicators and estimate production deficits using a probabilistic approach.

  16. Response of Thematic Mapper bands to plant water stress

    Science.gov (United States)

    Cibula, W. G.; Zetka, E. F.; Rickman, D. L.

    1992-01-01

    Changes in leaf reflectance as water content decreases have been hypothesized to occur in the 1.55-1.75 and 2.08-2.35 micron wavelength regions. To evaluate this hypothesis, studies were conducted on ryegrass (Lolium multiflorum Lam.) and oats (Avena sativa L.), which were grown in a controlled, outdoor situation. Both fully-watered control beds and water-stressed beds were periodically examined with a spectroradiometer calibrated against a reflectance reference of polytetrafluoroethylene. The observed changes correspond to those predicted by stochastic leaf models employed by other investigators (leaf reflection increases in the 1.55-1.75 micron region as leaf water content decreases). Although the percentage changes in TM bands 1-3 are nearly as great as those found in TM bands 5 and 7, the absolute values of reflectance change are much lower. It is believed that these patterns are probably characteristic of a broad range of vegetation types. In terms of phenomena detection, these patterns should be considered in any practical remote sensing sensor scenario.

  17. Global water resources affected by human interventionss and climate change

    NARCIS (Netherlands)

    Haddeland, I.; Heinke, J.; Biemans, H.; Eisner, S.; Florke, M.F.; Hanasaki, N.; Konzmann, M.; Ludwig, F.

    2014-01-01

    Humans directly change the dynamics of the water cycle through dams constructed for water storage, and through water withdrawals for industrial, agricultural, or domestic purposes. Climate change is expected to additionally affect water supply and demand. Here, analyses of climate change and direct

  18. Global water resources affected by human interventions and climate change

    NARCIS (Netherlands)

    Haddeland, I.; Heinke, J.; Biemans, H.; Eisner, S.; Flörke, M.; Hanasaki, N.; Konzmann, M.; Ludwig, F.; Masaki, Y.; Schewe, J.; Stacke, T.; Tessler, Z.; Wada, Y.|info:eu-repo/dai/nl/341387819; Wisser, D.

    2014-01-01

    Humans directly change the dynamics of the water cycle through dams constructed for water storage, and through water withdrawals for industrial, agricultural, or domestic purposes. Climate change is expected to additionally affect water supply and demand. Here, analyses of climate change and direct

  19. Comparative leaf proteomics of drought-tolerant and -susceptible peanut in response to water stress

    Science.gov (United States)

    Water stress (WS) predisposes peanut plants to fungal infection resulting in pre-harvest aflatoxin contamination. Major changes during water stress including oxidative stress, lead to destruction of photosynthetic apparatus and other macromolecules within cells. Two peanut cultivars with diverse dro...

  20. A Framework for Assessing Soil Moisture Deficit and Crop Water Stress at Multiple Space and Time Scales Under Climate Change Scenarios Using Model Platform, Satellite Remote Sensing, and Decision Support System

    KAUST Repository

    Mohanty, Binayak P.; Ines, Amor V. M.; Shin, Yongchul; Gaur, Nandita; Das, Narendra; Jana, Raghavendra Belur

    2016-01-01

    for sustainability of the growing global population. This warrants better predictive tools for aridity (based on precipitation, temperature, land use, and land cover), root zone (~top 1 m) soil moisture deficit, and crop water stress at farm, county, state, region

  1. Global crop yield response to extreme heat stress under multiple climate change futures

    International Nuclear Information System (INIS)

    Deryng, Delphine; Warren, Rachel; Conway, Declan; Ramankutty, Navin; Price, Jeff

    2014-01-01

    Extreme heat stress during the crop reproductive period can be critical for crop productivity. Projected changes in the frequency and severity of extreme climatic events are expected to negatively impact crop yields and global food production. This study applies the global crop model PEGASUS to quantify, for the first time at the global scale, impacts of extreme heat stress on maize, spring wheat and soybean yields resulting from 72 climate change scenarios for the 21st century. Our results project maize to face progressively worse impacts under a range of RCPs but spring wheat and soybean to improve globally through to the 2080s due to CO 2 fertilization effects, even though parts of the tropic and sub-tropic regions could face substantial yield declines. We find extreme heat stress at anthesis (HSA) by the 2080s (relative to the 1980s) under RCP 8.5, taking into account CO 2 fertilization effects, could double global losses of maize yield (ΔY = −12.8 ± 6.7% versus − 7.0 ± 5.3% without HSA), reduce projected gains in spring wheat yield by half (ΔY = 34.3 ± 13.5% versus 72.0 ± 10.9% without HSA) and in soybean yield by a quarter (ΔY = 15.3 ± 26.5% versus 20.4 ± 22.1% without HSA). The range reflects uncertainty due to differences between climate model scenarios; soybean exhibits both positive and negative impacts, maize is generally negative and spring wheat generally positive. Furthermore, when assuming CO 2 fertilization effects to be negligible, we observe drastic climate mitigation policy as in RCP 2.6 could avoid more than 80% of the global average yield losses otherwise expected by the 2080s under RCP 8.5. We show large disparities in climate impacts across regions and find extreme heat stress adversely affects major producing regions and lower income countries. (paper)

  2. Net carbon allocation in soybean seedlings as influenced by soil water stress at two soil temperatures

    International Nuclear Information System (INIS)

    McCoy, E.L.; Boersma, L.; Ekasingh, M.

    1990-01-01

    The influence of water stress at two soil temperatures on allocation of net photoassimilated carbon in soybean (Glycine max [L.] Merr.) was investigated using compartmental analysis. The experimental phase employed classical 14 C labeling methodology with plants equilibrated at soil water potentials of -0.04, -0.25 and -0.50 MPa; and soil temperatures of 25 and 10C. Carbon immobilization in the shoot apex generally followed leaf elongation rates with decreases in both parameters at increasing water stress at both soil temperatures. However, where moderate water stress resulted in dramatic declines in leaf elongation rates, carbon immobilization rates were sharply decreased only at severe water stress levels. Carbon immobilization was decreased in the roots and nodules of the nonwater stressed treatment by the lower soil temperature. This relation was reversed with severe water stress, and carbon immobilization in the roots and nodules was increased at the lower soil temperature. Apparently, the increased demand for growth and/or carbon storage in these tissues with increased water stress overcame the low soil temperature limitations. Both carbon pool sizes and partitioning of carbon to the sink tissues increased with moderate water stress at 25C soil temperature. Increased pool sizes were consistent with whole plant osmotic adjustment at moderate water stress. Increased partitioning to the sinks was consistent with carbon translocation processes being less severely influenced by water stress than is photosynthesis

  3. Does global progress on sanitation really lag behind water? An analysis of global progress on community- and household-level access to safe water and sanitation.

    Science.gov (United States)

    Cumming, Oliver; Elliott, Mark; Overbo, Alycia; Bartram, Jamie

    2014-01-01

    Safe drinking water and sanitation are important determinants of human health and wellbeing and have recently been declared human rights by the international community. Increased access to both were included in the Millennium Development Goals under a single dedicated target for 2015. This target was reached in 2010 for water but sanitation will fall short; however, there is an important difference in the benchmarks used for assessing global access. For drinking water the benchmark is community-level access whilst for sanitation it is household-level access, so a pit latrine shared between households does not count toward the Millennium Development Goal (MDG) target. We estimated global progress for water and sanitation under two scenarios: with equivalent household- and community-level benchmarks. Our results demonstrate that the "sanitation deficit" is apparent only when household-level sanitation access is contrasted with community-level water access. When equivalent benchmarks are used for water and sanitation, the global deficit is as great for water as it is for sanitation, and sanitation progress in the MDG-period (1990-2015) outstrips that in water. As both drinking water and sanitation access yield greater benefits at the household-level than at the community-level, we conclude that any post-2015 goals should consider a household-level benchmark for both.

  4. Implicit learning in transient global amnesia and the role of stress

    Directory of Open Access Journals (Sweden)

    Frauke Nees

    2016-11-01

    Full Text Available Transient global amnesia (TGA is a disorder with reversible anterograde disturbance of explicit memory, frequently preceded by an emotionally or physically stressful event. By using magnetic resonance imaging (MRI following an episode of TGA, small hippocampal lesions have been observed. Hence it has been postulated that the disorder is caused by the stress-related transient inhibition of memory formation in the hippocampus. In experimental studies, stress has been shown to affect both explicit and implicit learning – the latter defined as learning and memory processes that lack conscious awareness of the information acquired. To test the hypothesis that impairment of implicit learning in TGA is present and related to stress, we determined the effect of experimental exposure to stress on hippocampal activation patterns during an implicit learning paradigm in patients who suffered a recent TGA and healthy matched control subjects. We used a hippocampus-dependent aversive learning procedure (context conditioning with the phases habituation, acquisition, and extinction during functional MRI following experimental stress exposure (socially evaluated cold pressor test. After a control procedure, controls showed successful learning during the acquisition phase, indicated by increased valence, arousal and contingency ratings to the paired (CON+ versus the non-paired (CON- conditioned stimulus, and successful extinction of the conditioned responses. Following stress, acquisition was still successful, however extinction was impaired with persistently increased contingency ratings. In contrast, TGA patients showed impairment of conditioned responses and insufficient extinction after the control procedure, indicated by a lack of significant differences between CON+ and CON- for valence and arousal ratings after the acquisition phase and by significantly increased contingency ratings after the extinction. After stress, aversive learning was not successful

  5. Global Analysis of WRKY Genes and Their Response to Dehydration and Salt Stress in Soybean.

    Science.gov (United States)

    Song, Hui; Wang, Pengfei; Hou, Lei; Zhao, Shuzhen; Zhao, Chuanzhi; Xia, Han; Li, Pengcheng; Zhang, Ye; Bian, Xiaotong; Wang, Xingjun

    2016-01-01

    WRKY proteins are plant specific transcription factors involved in various developmental and physiological processes, especially in biotic and abiotic stress resistance. Although previous studies suggested that WRKY proteins in soybean (Glycine max var. Williams 82) involved in both abiotic and biotic stress responses, the global information of WRKY proteins in the latest version of soybean genome (Wm82.a2v1) and their response to dehydration and salt stress have not been reported. In this study, we identified 176 GmWRKY proteins from soybean Wm82.a2v1 genome. These proteins could be classified into three groups, namely group I (32 proteins), group II (120 proteins), and group III (24 proteins). Our results showed that most GmWRKY genes were located on Chromosome 6, while chromosome 11, 12, and 20 contained the least number of this gene family. More GmWRKY genes were distributed on the ends of chromosomes to compare with other regions. The cis-acting elements analysis suggested that GmWRKY genes were transcriptionally regulated upon dehydration and salt stress. RNA-seq data analysis indicated that three GmWRKY genes responded negatively to dehydration, and 12 genes positively responded to salt stress at 1, 6, and 12 h, respectively. We confirmed by qRT-PCR that the expression of GmWRKY47 and GmWRKY 58 genes was decreased upon dehydration, and the expression of GmWRKY92, 144 and 165 genes was increased under salt treatment.

  6. Energetic Consequences of nitrite stress in Desulfovibrio vulgarisHildenborough, inferred from global transcriptional analysis

    Energy Technology Data Exchange (ETDEWEB)

    He, Qiang; Huang, Katherine H.; He, Zhili; Alm, Eric J.; Fields,Matthew W.; Hazen, Terry C.; Arkin, Adam P.; Wall, Judy D.; Zhou, Jizhong

    2005-11-03

    Many of the proteins that are candidates for bioenergetic pathways involved with sulfate respiration in Desulfovibrio spp. have been studied, but complete pathways and overall cell physiology remain to be resolved for many environmentally relevant conditions. In order to understand the metabolism of these microorganisms under adverse environmental conditions for improved bioremediation efforts, Desulfovibrio vulgaris Hildenborough was used as a model organism to study stress response to nitrite, an important intermediate in the nitrogen cycle. Previous physiological studies demonstrated that growth was inhibited by nitrite and that nitrite reduction was observed to be the primary mechanism of detoxification. Global transcriptional profiling with whole-genome microarrays revealed coordinated cascades of responses to nitrite in pathways of energy metabolism, nitrogen metabolism, oxidative stress response, and iron homeostasis. In agreement with previous observations, nitrite-stressed cells showed a decrease in the expression of genes encoding sulfate reduction functions in addition to respiratory oxidative phosphorylation and ATP synthase activity. Consequently, the stressed cells had decreased expression of the genes encoding ATP-dependent amino acid transporters and proteins involved in translation. Other genes up-regulated in response to nitrite include the genes in the Fur regulon, which is suggested to be involved in iron homeostasis, and genes in the Per regulon, which is predicted to be responsible for oxidative stress response.

  7. Modeling Global Water Use for the 21st Century: Water Futures and Solutions (WFaS) Initiative and Its Approaches

    Science.gov (United States)

    Wada, Y.; Florke, M.; Hanasaki, N.; Eisner, S.; Fischer, G.; Tramberend, S.; Satoh, Y.; van Vliet, M. T. H.; Yillia, P.; Ringler, C.; hide

    2016-01-01

    To sustain growing food demand and increasing standard of living, global water use increased by nearly 6 times during the last 100 years, and continues to grow. As water demands get closer and closer to the water availability in many regions, each drop of water becomes increasingly valuable and water must be managed more efficiently and intensively. However, soaring water use worsens water scarcity conditions already prevalent in semi-arid and arid regions, increasing uncertainty for sustainable food production and economic development. Planning for future development and investments requires that we prepare water projections for the future. However, estimations are complicated because the future of the world's waters will be influenced by a combination of environmental, social, economic, and political factors, and there is only limited knowledge and data available about freshwater resources and how they are being used. The Water Futures and Solutions (WFaS) initiative coordinates its work with other ongoing scenario efforts for the sake of establishing a consistent set of new global water scenarios based on the shared socio-economic pathways (SSPs) and the representative concentration pathways (RCPs). The WFaS "fast track" assessment uses three global water models, namely H08, PCR-GLOBWB, and WaterGAP. This study assesses the state of the art for estimating and projecting water use regionally and globally in a consistent manner. It provides an overview of different approaches, the uncertainty, strengths and weaknesses of the various estimation methods, types of management and policy decisions for which the current estimation methods are useful. We also discuss additional information most needed to be able to improve water use estimates and be able to assess a greater range of management options across the water-energy-climate nexus.

  8. Arsenic in Drinking Water-A Global Environmental Problem

    Science.gov (United States)

    Wang, Joanna Shaofen; Wai, Chien M.

    2004-01-01

    Information on the worldwide occurrence of groundwater pollution by arsenic, the ensuing health hazards, and the debatable government regulations of arsenic in drinking water, is presented. Diagnostic identification of arsenic, and methods to eliminate it from water are also discussed.

  9. Effect of soil water stress on yield and proline content of four wheat ...

    African Journals Online (AJOL)

    Effect of soil water stress on yield and proline content of four wheat lines. ... This field study was conducted to evaluate the effect of drought stress after anthesis on proline accumulation and wheat yield during 2008 at ... from 32 Countries:.

  10. Global transcriptome profile of Cryptococcus neoformans during exposure to hydrogen peroxide induced oxidative stress.

    Directory of Open Access Journals (Sweden)

    Rajendra Upadhya

    Full Text Available The ability of the opportunistic fungal pathogen Cryptococcus neoformans to resist oxidative stress is one of its most important virulence related traits. To cope with the deleterious effect of cellular damage caused by the oxidative burst inside the macrophages, C. neoformans has developed multilayered redundant molecular responses to neutralize the stress, to repair the damage and to eventually grow inside the hostile environment of the phagosome. We used microarray analysis of cells treated with hydrogen peroxide (H(2O(2 at multiple time points in a nutrient defined medium to identify a transcriptional signature associated with oxidative stress. We discovered that the composition of the medium in which fungal cells were grown and treated had a profound effect on their capacity to degrade exogenous H(2O(2. We determined the kinetics of H(2O(2 breakdown by growing yeast cells under different conditions and accordingly selected an appropriate media composition and range of time points for isolating RNA for hybridization. Microarray analysis revealed a robust transient transcriptional response and the intensity of the global response was consistent with the kinetics of H(2O(2 breakdown by treated cells. Gene ontology analysis of differentially expressed genes related to oxidation-reduction, metabolic process and protein catabolic processes identified potential roles of mitochondrial function and protein ubiquitination in oxidative stress resistance. Interestingly, the metabolic pathway adaptation of C. neoformans to H(2O(2 treatment was remarkably distinct from the response of other fungal organisms to oxidative stress. We also identified the induction of an antifungal drug resistance response upon the treatment of C. neoformans with H(2O(2. These results highlight the complexity of the oxidative stress response and offer possible new avenues for improving our understanding of mechanisms of oxidative stress resistance in C. neoformans.

  11. The crop water stress index (CWSI) for drip irrigated cotton in a semi ...

    African Journals Online (AJOL)

    The crop water stress index (CWSI) for drip irrigated cotton in a semi-arid region of Turkey. ... Four irrigation treatments designated as full (I100) with no water stress and slight (DI70), moderate (DI50) and strong water ... from 32 Countries:.

  12. Water Stress Assessment in Jharkhand State Using Soil Data and GIS

    African Journals Online (AJOL)

    In this paper an attempt has been made to study the interrelationship of water resources available with that of soil class and its properties including soil drainage and erosional characteristics which has been used to generate drainage stress map and water stress map inferring the basic reason for water scarcity in the district ...

  13. The impacts of water stress on phloem transport in Douglas-fir trees

    Science.gov (United States)

    David Woodruff

    2014-01-01

    Despite the critical role that phloem plays in a number of plant functional processes and the potential impact of water stress on phloem structural and phloem sap compositional characteristics, little research has been done to examine how water stress influences phloem transport. The objectives of this study were to develop a more accurate understanding of how water...

  14. Measuring global water security towards sustainable development goals

    NARCIS (Netherlands)

    Wada, Y.|info:eu-repo/dai/nl/341387819; Gain, A.K.; Giupponi, C.

    2016-01-01

    Water plays an important role in underpinning equitable, stable and productive societies and ecosystems. Hence, United Nations recognized ensuring water security as one (Goal 6) of the seventeen sustainable development goals(SDGs). Many international river basins are likely to experience ‘low water

  15. GEWEX: The Global Energy and Water Cycle Experiment

    Science.gov (United States)

    Chahine, M.; Vane, D.

    1994-01-01

    GEWEX is one of the world's largest global change research programs. Its purpose is to observe and understand the hydrological cycle and energy fluxes in the atmosphere, at land surfaces and in the upper oceans.

  16. Future Freshwater Stress on Small Islands: Population, Aridity and Global Warming Targets

    Science.gov (United States)

    Karnauskas, K. B.; Schleussner, C. F.; Donnelly, J. P.; Anchukaitis, K. J.

    2017-12-01

    Small island developing states (SIDS) face multiple threats from anthropogenic climate change, including potential changes in freshwater resource availability. Future freshwater stress, including geographic and seasonal variability, has important implications for climate change adaptation scenarios for vulnerable human populations living on islands across the world ocean. Due to a mismatch in spatial scale between SIDS landforms and the horizontal resolution of global climate models (GCMs), SIDS are mostly unaccounted for in GCMs that are used to make future projections of global climate change and its regional impacts. Specific approaches are required to address this gap between broad-scale model projections and regional, policy-relevant outcomes. Here we apply a recently developed methodology to project future changes in aridity in combination with population projections associated with different shared socioeconomic pathways (SSPs) to evaluate overall changes in freshwater stress in SIDS at warming levels of 1.5°C and 2°C above pre-industrial levels. By accounting for evaporative demand a posteriori, we reveal a robust yet spatially variable tendency towards increasing aridity for 16 million people living on islands by mid-century. Although about half of the islands are projected to experience increased rainfall—predominantly in the deep tropics—projected changes in evaporation are more uniform, shifting the global distribution of changes in island freshwater balance towards greater aridity. In many cases, the magnitude of projected drying is comparable to the amplitude of the estimated observed interannual variability, with important consequences for extreme events. While we find that future population growth will dominate changes in projected freshwater stress especially towards the end of the century, projected changes in aridity are found to compound freshwater stress for the vast majority of SIDS. Particularly across the Caribbean region, a

  17. Sectoral contributions to surface water stress in the coterminous United States

    International Nuclear Information System (INIS)

    Averyt, K; Meldrum, J; Caldwell, P; Sun, G; McNulty, S; Huber-Lee, A; Madden, N

    2013-01-01

    Here, we assess current stress in the freshwater system based on the best available data in order to understand possible risks and vulnerabilities to regional water resources and the sectors dependent on freshwater. We present watershed-scale measures of surface water supply stress for the coterminous United States (US) using the water supply stress index (WaSSI) model which considers regional trends in both water supply and demand. A snapshot of contemporary annual water demand is compared against different water supply regimes, including current average supplies, current extreme-year supplies, and projected future average surface water flows under a changing climate. In addition, we investigate the contributions of different water demand sectors to current water stress. On average, water supplies are stressed, meaning that demands for water outstrip natural supplies in over 9% of the 2103 watersheds examined. These watersheds rely on reservoir storage, conveyance systems, and groundwater to meet current water demands. Overall, agriculture is the major demand-side driver of water stress in the US, whereas municipal stress is isolated to southern California. Water stress introduced by cooling water demands for power plants is punctuated across the US, indicating that a single power plant has the potential to stress water supplies at the watershed scale. On the supply side, watersheds in the western US are particularly sensitive to low flow events and projected long-term shifts in flow driven by climate change. The WaSSI results imply that not only are water resources in the southwest in particular at risk, but that there are also potential vulnerabilities to specific sectors, even in the ‘water-rich’ southeast. (letter)

  18. Enhanced water use efficiency in global terrestrial ecosystems under increasing aerosol loadings

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xiaoliang; Chen, Min; Liu, Yaling; Miralles, Diego G.; Wang, Faming

    2017-05-01

    Aerosols play a crucial role in the climate system, affecting incoming radiation and cloud formation. Based on a modelling framework that couples ecosystem processes with the atmospheric transfer of radiation, we analyze the effect of aerosols on surface incoming radiation, gross primary productivity (GPP), water losses from ecosystems through evapotranspiration (ET) and ecosystem water use efficiency (WUE, defined as GPP/ET) for 2003–2010 and validate them at global FLUXNET sites. The total diffuse radiation increases under relatively low or intermediate aerosol loadings, but decreases under more polluted conditions. We find that aerosol-induced changes in GPP depend on leaf area index, aerosol loading and cloudiness. Specifically, low and moderate aerosol loadings cause increases in GPP for all plant types, while heavy aerosol loadings result in enhancement (decrease) in GPP for dense (sparse) vegetation. On the other hand, ET is mainly negatively affected by aerosol loadings due to the reduction in total incoming radiation. Finally, WUE shows a consistent rise in all plant types under increasing aerosol loadings. Overall, the simulated daily WUE compares well with observations at 43 eddy-covariance tower sites (R2=0.84 and RMSE=0.01gC (kg H2O)-1) with better performance at forest sites. In addition to the increasing portions of diffuse light, the rise in WUE is also favored by the reduction in radiation- and heat-stress caused by the aerosols, especially for wet and hot climates.

  19. Through the Looking Glass of Global Constitutionalism and Global Administrative Law : Different Stories About the Crisis in Global Water Governance?

    NARCIS (Netherlands)

    M. Ambrus (Mónika)

    2013-01-01

    textabstractIn addition to (or sometimes rather than primarily) attribut- ing it to water scarcity, water crisis has been described as a ‘crisis of governance’; with the word ‘crisis’ also indicating that water governance lacks (full) legitimacy. The article undertakes the task to analyse the

  20. Energy-Water-Land Nexus: The relative contributions of climate and human systems on global water scarcity

    Science.gov (United States)

    Hejazi, M. I.; Chen, M.; Turner, S. W. D.; Graham, N. T.; Vernon, C. R.; Li, X.; Kim, S. H.; Link, R. P.

    2017-12-01

    There is a growing consensus that energy, water, and land systems are interconnected and should be analyzed as such. New tools are required to represent the interactions between population, economic growth, energy, land, and water resources in a dynamically evolving system. Here we use the Global Change Assessment Model (GCAM) to investigate the relative contributions of climate and human systems on water scarcity regionally and globally under a wide range of scenarios. The model accounts for a variety of human activities, including changing demands for water for agriculture, power generation, industry, and public supply. We find that these activities exert a larger influence on water scarcity than climate in 93% of river basins globally. This work highlights the importance of accounting for human activities in hydrologic modeling applications and how they may change under different pathways of how land use and agricultural systems, energy systems, and economies may evolve in the future.

  1. Global effects of local food-production crises: a virtual water perspective.

    Science.gov (United States)

    Tamea, Stefania; Laio, Francesco; Ridolfi, Luca

    2016-01-25

    By importing food and agricultural goods, countries cope with the heterogeneous global water distribution and often rely on water resources available abroad. The virtual displacement of the water used to produce such goods (known as virtual water) connects together, in a global water system, all countries participating to the international trade network. Local food-production crises, having social, economic or environmental origin, propagate in this network, modifying the virtual water trade and perturbing local and global food availability, quantified in terms of virtual water. We analyze here the possible effects of local crises by developing a new propagation model, parsimonious but grounded on data-based and statistically-verified assumptions, whose effectiveness is proved on the Argentinean crisis in 2008-09. The model serves as the basis to propose indicators of crisis impact and country vulnerability to external food-production crises, which highlight that countries with largest water resources have the highest impact on the international trade, and that not only water-scarce but also wealthy and globalized countries are among the most vulnerable to external crises. The temporal analysis reveals that global average vulnerability has increased over time and that stronger effects of crises are now found in countries with low food (and water) availability.

  2. Modelling water use in global hydrological models: review, challenges and directions

    Science.gov (United States)

    Bierkens, M. F.; de Graaf, I.; Wada, Y.; Wanders, N.; Van Beek, L. P.

    2017-12-01

    During the late 1980s and early 1990s, awareness of the shortage of global water resources lead to the first detailed global water resources assessments using regional statistics of water use and observations of meteorological and hydrological variables. Shortly thereafter, the first macroscale hydrological models (MHM) appeared. In these models, blue water (i.e., surface water and renewable groundwater) availability was calculated by accumulating runoff over a stream network and comparing it with population densities or with estimated water demand for agriculture, industry and households. In this talk we review the evolution of human impact modelling in global land models with a focus on global water resources, touching upon developments of the last 15 years: i.e. calculating human water scarcity; estimating groundwater depletion; adding dams and reservoirs; fully integrating water use (demand, withdrawal, consumption, return flow) in the hydrology; simulating the effects of land use change. We show example studies for each of these steps. We identify We identify major challenges that hamper the further development of integrated water resources modelling. Examples of these are: 1) simulating reservoir operations; 2) including local infrastructure and redistribution; 3) using the correct allocations rules; 4) projecting future water demand and water use. For each of these challenges we signify promising directions for further research.

  3. Global modeling of withdrawal, allocation and consumptive use of surface water and groundwater resources

    NARCIS (Netherlands)

    Wada, Y.; Wisser, D.; Bierkens, M.F.P.

    2013-01-01

    To sustain growing food demand and increasing standard of living, global water withdrawal and consumptive water use have been increasing rapidly. To analyze the human perturbation on water resources consistently over a large scale, a number of macro-scale hydrological models (MHMs) have been

  4. Global modeling of withdrawal, allocation and consumptive use of surface water and groundwater resources

    NARCIS (Netherlands)

    Wada, Y.; Wisser, D.; Bierkens, M. F. P.

    2014-01-01

    To sustain growing food demand and increasing standard of living, global water withdrawal and consumptive water use have been increasing rapidly. To analyze the human perturbation on water resources consistently over large scales, a number of macro-scale hydrological models (MHMs) have been

  5. 76 FR 10892 - Aquatic Ecosystems, Water Quality, and Global Change: Challenges of Conducting Multi-Stressor...

    Science.gov (United States)

    2011-02-28

    ...: EPA is announcing the release of the draft report titled, ``Aquatic Ecosystems, Water Quality, and... relative vulnerability of water quality and aquatic ecosystems, across the United States, to the potential... mailing address, and the document title, ``Aquatic Ecosystems, Water Quality, and Global Change...

  6. Beyond peak reservoir storage? A global estimate of declining water storage capacity in large reservoirs

    NARCIS (Netherlands)

    Wisser, D.; Frolking, S.; Hagen, Stephen; Bierkens, M.F.P.|info:eu-repo/dai/nl/125022794

    2013-01-01

    Water storage is an important way to cope with temporal variation in water supply anddemand. The storage capacity and the lifetime of water storage reservoirs can besignificantly reduced by the inflow of sediments. A global, spatially explicit assessment ofreservoir storage loss in conjunction with

  7. Crop water-stress assessment using an airborne thermal scanner

    Science.gov (United States)

    Millard, J. P.; Jackson, R. D.; Reginato, R. J.; Idso, S. B.; Goettelman, R. C.

    1978-01-01

    An airborne thermal scanner was used to measure the temperature of a wheat crop canopy in Phoenix, Arizona. The results indicate that canopy temperatures acquired about an hour and a half past solar noon were well correlated with presunrise plant water tension, a parameter directly related to plant growth and development. Pseudo-colored thermal images reading directly in stress degree days, a unit indicative of crop irrigation needs and yield potential, were produced. The aircraft data showed significant within-field canopy temperature variability, indicating the superiority of the synoptic view provided by aircraft over localized ground measurements. The standard deviation between airborne and ground-acquired canopy temperatures was 2 C or less.

  8. Technologies for water resources management: an integrated approach to manage global and regional water resources

    Energy Technology Data Exchange (ETDEWEB)

    Tao, W. C., LLNL

    1998-03-23

    regional water resources; As an evaluation tool for selecting appropriate remediation technologies for reclaiming water; and As an assessment tool for determining the effectiveness of implementing the remediation technologies. We have included a discussion on the appropriate strategy for LLNL to integrate its technical tools into the global business, geopolitical, and academic communities, whereby LLNL can form partnerships with technology proponents in the commercial, industrial, and public sectors.

  9. Abscisic acid biosynthesis in water-stressed leaves

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yi.

    1989-01-01

    Although abscisic acid (ABA) was discovered 30 years ago, very little is known about its biosynthetic pathway in higher plants. Two hypotheses have been proposed: (i) a direct pathway involving only C-15 intermediates like farnesyl pyrophosphate, (ii) an indirect pathway involving C-40 intermediates like the xanthophylls. When {sup 14}CO{sub 2} was fed into greened bean plants, the {sup 14}C specific activity of ABA was always lower than those in xanthophylls, such as violaxanthin and lutein, regardless of {sup 12}CO{sub 2} chase periods. The ABA accumulation in green leaves was not affected by fluridone when plants were stressed once, but the {sup 14}C incorporation into ABA was inhibited to the same extent as those of xanthophylls. The incorporation of {sup 18}O into the ABA ring when violaxanthin was labeled by {sup 18}O in vivo via the violaxanthin cycle indicates that at least a portion of ABA was derived from {sup 18}O-labeled violaxanthin during water stress.

  10. Water relations and gas exchange in poplar and willow under water stress and elevated atmospheric CO2.

    Science.gov (United States)

    Johnson, Jon D; Tognetti, Roberto; Paris, Piero

    2002-05-01

    Predictions of shifts in rainfall patterns as atmospheric [CO2] increases could impact the growth of fast growing trees such as Populus spp. and Salix spp. and the interaction between elevated CO2 and water stress in these species is unknown. The objectives of this study were to characterize the responses to elevated CO2 and water stress in these two species, and to determine if elevated CO2 mitigated drought stress effects. Gas exchange, water potential components, whole plant transpiration and growth response to soil drying and recovery were assessed in hybrid poplar (clone 53-246) and willow (Salix sagitta) rooted cuttings growing in either ambient (350 &mgr;mol mol-1) or elevated (700 &mgr;mol mol-1) atmospheric CO2 concentration ([CO2]). Predawn water potential decreased with increasing water stress while midday water potentials remained unchanged (isohydric response). Turgor potentials at both predawn and midday increased in elevated [CO2], indicative of osmotic adjustment. Gas exchange was reduced by water stress while elevated [CO2] increased photosynthetic rates, reduced leaf conductance and nearly doubled instantaneous transpiration efficiency in both species. Dark respiration decreased in elevated [CO2] and water stress reduced Rd in the trees growing in ambient [CO2]. Willow had 56% lower whole plant hydraulic conductivity than poplar, and showed a 14% increase in elevated [CO2] while poplar was unresponsive. The physiological responses exhibited by poplar and willow to elevated [CO2] and water stress, singly, suggest that these species respond like other tree species. The interaction of [CO2] and water stress suggests that elevated [CO2] did mitigate the effects of water stress in willow, but not in poplar.

  11. Morphological plasticity of root growth under mild water stress increases water use efficiency without reducing yield in maize

    Science.gov (United States)

    Cai, Qian; Zhang, Yulong; Sun, Zhanxiang; Zheng, Jiaming; Bai, Wei; Zhang, Yue; Liu, Yang; Feng, Liangshan; Feng, Chen; Zhang, Zhe; Yang, Ning; Evers, Jochem B.; Zhang, Lizhen

    2017-08-01

    A large yield gap exists in rain-fed maize (Zea mays L.) production in semi-arid regions, mainly caused by frequent droughts halfway through the crop-growing period due to uneven distribution of rainfall. It is questionable whether irrigation systems are economically required in such a region since the total amount of rainfall does generally meet crop requirements. This study aimed to quantitatively determine the effects of water stress from jointing to grain filling on root and shoot growth and the consequences for maize grain yield, above- and below-ground dry matter, water uptake (WU) and water use efficiency (WUE). Pot experiments were conducted in 2014 and 2015 with a mobile rain shelter to achieve conditions of no, mild or severe water stress. Maize yield was not affected by mild water stress over 2 years, while severe stress reduced yield by 56 %. Both water stress levels decreased root biomass slightly but shoot biomass substantially. Mild water stress decreased root length but increased root diameter, resulting in no effect on root surface area. Due to the morphological plasticity in root growth and the increase in root / shoot ratio, WU under water stress was decreased, and overall WUE for both above-ground dry matter and grain yield increased. Our results demonstrate that an irrigation system might be not economically and ecologically necessary because the frequently occurring mild water stress did not reduce crop yield much. The study helps us to understand crop responses to water stress during a critical water-sensitive period (middle of the crop-growing season) and to mitigate drought risk in dry-land agriculture.

  12. Morphological plasticity of root growth under mild water stress increases water use efficiency without reducing yield in maize

    Directory of Open Access Journals (Sweden)

    Q. Cai

    2017-08-01

    Full Text Available A large yield gap exists in rain-fed maize (Zea mays L. production in semi-arid regions, mainly caused by frequent droughts halfway through the crop-growing period due to uneven distribution of rainfall. It is questionable whether irrigation systems are economically required in such a region since the total amount of rainfall does generally meet crop requirements. This study aimed to quantitatively determine the effects of water stress from jointing to grain filling on root and shoot growth and the consequences for maize grain yield, above- and below-ground dry matter, water uptake (WU and water use efficiency (WUE. Pot experiments were conducted in 2014 and 2015 with a mobile rain shelter to achieve conditions of no, mild or severe water stress. Maize yield was not affected by mild water stress over 2 years, while severe stress reduced yield by 56 %. Both water stress levels decreased root biomass slightly but shoot biomass substantially. Mild water stress decreased root length but increased root diameter, resulting in no effect on root surface area. Due to the morphological plasticity in root growth and the increase in root ∕ shoot ratio, WU under water stress was decreased, and overall WUE for both above-ground dry matter and grain yield increased. Our results demonstrate that an irrigation system might be not economically and ecologically necessary because the frequently occurring mild water stress did not reduce crop yield much. The study helps us to understand crop responses to water stress during a critical water-sensitive period (middle of the crop-growing season and to mitigate drought risk in dry-land agriculture.

  13. Flexible riser global analysis for very shallow water

    OpenAIRE

    Karegar, Sadjad

    2013-01-01

    Master's thesis in Offshore technology Flexible risers are widely used for a range of water depths and can accommodate large floater motions when using a buoyant system. A wide range of buoyancy solutions have been developed for very shallow water (e.g. 30-50 m), shallow water (e.g. 90-110 m) and semi-deep water (e.g. 300-400 m) and in the ranges between these depths. Flexible risers can have different configurations. These different solutions have different characteristics which influe...

  14. Global contexts, social capital, and acculturative stress: experiences of Indian immigrant men in New York City.

    Science.gov (United States)

    Bhattacharya, Gauri

    2011-08-01

    Immigrants depend on within-group social networks for social support during the acculturation process. Within-group social networks are linked to higher mutual concern and reciprocity, lower acculturative stress, and lower depression among immigrants Studies are limited, however, about immigrants' social support in the contexts of global connectedness and transnational connectivity. Grounded in social capital approach and immigrant health framework, this qualitative, community-based study examined the social networks of immigrant men from India to New York City. Drawing upon the participants' narratives, the author illustrates the ways that social capital influences social networking and acculturative stress in post-immigration sociocultural contexts along with its implications for community-based interventions.

  15. GlobWat – a global water balance model to assess water use in irrigated agriculture (discussion paper)

    NARCIS (Netherlands)

    Hoogeveen, J.; Faures, J.M.; Peiser, L.; Burke, J.; Van de Giesen, N.C.

    2015-01-01

    GlobWat is a freely distributed, global soil water balance model that is used by FAO to assess water use in irrigated agriculture; the main factor behind scarcity of freshwater in an increasing number of regions. The model is based on spatially distributed high resolution datasets that are

  16. Ascorbic Acid Alleviates Water Stress in Young Peach Trees and Improves Their Performance after Rewatering

    Directory of Open Access Journals (Sweden)

    Consuelo Penella

    2017-09-01

    Full Text Available Exogenous application of biochemicals has been found to improve water stress tolerance in herbaceous crops but there are limited studies on deciduous fruit trees. The goal of this research was to study if ascorbic acid applications could improve physiological mechanisms associated with water stress tolerance in young fruit trees. Ascorbic acid was foliarly applied at a concentration of 250 ppm to water-stressed and well-watered peach trees (control of two cultivars (‘Scarletprince’ and ‘CaroTiger’. Trees received either one or two applications, and 1 week after the second application all trees were rewatered to field capacity. Upon rewatering, CO2 assimilation and stomatal conductance of water-stressed ‘Scarletprince’ trees sprayed with ascorbic acid (one or two applications were similar to those of well-irrigated trees, but water-stressed trees that had not received ascorbic acid did not recover photosynthetical functions. Also, water status in sprayed water-stressed ‘Scarletprince’ trees was improved to values similar to control trees. On the other hand, water-stressed ‘CaroTiger’ trees needed two applications of ascorbic acid to reach values of CO2 assimilation similar to control trees but these applications did not improve their water status. In general terms, different response mechanisms to cope with water stress in presence of ascorbic acid were found in each cultivar, with ‘Scarletprince’ trees preferentially using proline as compatible solute and ‘CaroTiger’ trees relying on stomatal regulation. The application of ascorbic acid reduced cell membrane damage and increased catalase activity in water-stressed trees of both cultivars. These results suggest that foliar applications of ascorbic acid could be used as a management practice for improving water stress tolerance of young trees under suboptimal water regimes.

  17. Ascorbic Acid Alleviates Water Stress in Young Peach Trees and Improves Their Performance after Rewatering.

    Science.gov (United States)

    Penella, Consuelo; Calatayud, Ángeles; Melgar, Juan C

    2017-01-01

    Exogenous application of biochemicals has been found to improve water stress tolerance in herbaceous crops but there are limited studies on deciduous fruit trees. The goal of this research was to study if ascorbic acid applications could improve physiological mechanisms associated with water stress tolerance in young fruit trees. Ascorbic acid was foliarly applied at a concentration of 250 ppm to water-stressed and well-watered peach trees (control) of two cultivars ('Scarletprince' and 'CaroTiger'). Trees received either one or two applications, and 1 week after the second application all trees were rewatered to field capacity. Upon rewatering, CO 2 assimilation and stomatal conductance of water-stressed 'Scarletprince' trees sprayed with ascorbic acid (one or two applications) were similar to those of well-irrigated trees, but water-stressed trees that had not received ascorbic acid did not recover photosynthetical functions. Also, water status in sprayed water-stressed 'Scarletprince' trees was improved to values similar to control trees. On the other hand, water-stressed 'CaroTiger' trees needed two applications of ascorbic acid to reach values of CO 2 assimilation similar to control trees but these applications did not improve their water status. In general terms, different response mechanisms to cope with water stress in presence of ascorbic acid were found in each cultivar, with 'Scarletprince' trees preferentially using proline as compatible solute and 'CaroTiger' trees relying on stomatal regulation. The application of ascorbic acid reduced cell membrane damage and increased catalase activity in water-stressed trees of both cultivars. These results suggest that foliar applications of ascorbic acid could be used as a management practice for improving water stress tolerance of young trees under suboptimal water regimes.

  18. Climate Change and Expected Impacts on the Global Water Cycle

    Science.gov (United States)

    Rind, David; Hansen, James E. (Technical Monitor)

    2002-01-01

    How the elements of the global hydrologic cycle may respond to climate change is reviewed, first from a discussion of the physical sensitivity of these elements to changes in temperature, and then from a comparison of observations of hydrologic changes over the past 100 million years. Observations of current changes in the hydrologic cycle are then compared with projected future changes given the prospect of global warming. It is shown that some of the projections come close to matching the estimated hydrologic changes that occurred long ago when the earth was very warm.

  19. Welding residual stress improvement in internal components by water jet peening

    International Nuclear Information System (INIS)

    Enomoto, K.; Hirano, K.; Hayashi, M.; Hayashi, E.

    1996-01-01

    Cavitations are generated when highly pressurized water is jetted in water. Surface residual stress is improved remarkably due to the peening effect of extremely high pressure caused by the collapse of cavitation bubbles. This technique is called water jet peening (WJP). WJP is expected to be an effective maintenance technique for the prevention of stress corrosion cracking caused by residual stress in various components of power generating plants. Various kinds of specimens were water jet peened to evaluate the fundamental characteristics of WJP and to select the most appropriate conditions for the residual stress improvement. Test results showed that WJP markedly improved the tensile residual stress caused by welding and grinding to the high compressive residual stress and seems to prevent the stress corrosion cracking

  20. Reported Exposure and Emotional Reactivity to Daily Stressors: The Roles of Adult-Age and Global Perceived Stress

    OpenAIRE

    Stawski, Robert S.; Sliwinski, Martin J.; Almeida, David M.; Smyth, Joshua M.

    2008-01-01

    A central goal of daily stress research is to identify resilience and vulnerability factors associated with exposure and reactivity to daily stressors. The current study examined how age differences and global perceptions of stress relate to exposure and emotional reactivity to daily stressors. Sixty-seven younger (Mage = 20) and 116 older (Mage = 80) adults completed a daily stress diary and measures of positive and negative affect on 6 days over a 14 day period. Participants also completed ...

  1. Safeguarding water availability for food and ecosystems under global change

    NARCIS (Netherlands)

    Pastor, Amandine V.

    2017-01-01

    In a context of future population increase and intensification of water cycle by climate change, water demand for irrigation is projected to double. However, freshwater resources have been degraded the last decades especially in rivers via fragmentation, dam contraction and pollution. Flow

  2. Local flow regulation and irrigation raise global human water consumption and footprint.

    Science.gov (United States)

    Jaramillo, Fernando; Destouni, Georgia

    2015-12-04

    Flow regulation and irrigation alter local freshwater conditions, but their global effects are highly uncertain. We investigated these global effects from 1901 to 2008, using hydroclimatic observations in 100 large hydrological basins. Globally, we find consistent and dominant effects of increasing relative evapotranspiration from both activities, and decreasing temporal runoff variability from flow regulation. The evapotranspiration effect increases the long-term average human consumption of fresh water by 3563 ± 979 km(3)/year from 1901-1954 to 1955-2008. This increase raises a recent estimate of the current global water footprint of humanity by around 18%, to 10,688 ± 979 km(3)/year. The results highlight the global impact of local water-use activities and call for their relevant account in Earth system modeling. Copyright © 2015, American Association for the Advancement of Science.

  3. Seasonal and global behavior of water vapor in the Mars atmosphere: Complete global results of the Viking atmospheric water detector experiment

    International Nuclear Information System (INIS)

    Jakosky, B.M.; Farmer, C.B.

    1982-01-01

    The water vapor content of the Mars atmosphere was measured from the Viking Orbiter Mars Atmospheric Water Detectors (MAWD) for a period of more than 1 Martian year, from June 1976 through April 1979. Results are presented in the form of global maps of column abundance for 24 periods throughout each Mars year. The data reduction incorporates spatial and seasonal variations in surface pressure and supplements earlier published versions of less complete data

  4. Role of aquaporins in determining transpiration and photosynthesis in water-stressed plants: crop water-use efficiency, growth and yield.

    Science.gov (United States)

    Moshelion, Menachem; Halperin, Ofer; Wallach, Rony; Oren, Ram; Way, Danielle A

    2015-09-01

    The global shortage of fresh water is one of our most severe agricultural problems, leading to dry and saline lands that reduce plant growth and crop yield. Here we review recent work highlighting the molecular mechanisms allowing some plant species and genotypes to maintain productivity under water stress conditions, and suggest molecular modifications to equip plants for greater production in water-limited environments. Aquaporins (AQPs) are thought to be the main transporters of water, small and uncharged solutes, and CO2 through plant cell membranes, thus linking leaf CO2 uptake from the intercellular airspaces to the chloroplast with water loss pathways. AQPs appear to play a role in regulating dynamic changes of root, stem and leaf hydraulic conductivity, especially in response to environmental changes, opening the door to using AQP expression to regulate plant water-use efficiency. We highlight the role of vascular AQPs in regulating leaf hydraulic conductivity and raise questions regarding their role (as well as tonoplast AQPs) in determining the plant isohydric threshold, growth rate, fruit yield production and harvest index. The tissue- or cell-specific expression of AQPs is discussed as a tool to increase yield relative to control plants under both normal and water-stressed conditions. © 2014 John Wiley & Sons Ltd.

  5. Pakistan's water resources development and the global perspective

    International Nuclear Information System (INIS)

    Mushtaq, M.; Sufi, A.B.

    2005-01-01

    Pakistan's economy is dependent on irrigated agriculture. About 80% of agriculture is irrigated. It contributes 30% of GDP. Agriculture provides 55% job opportunities. This sector provides 60% of country's exports. The development of agriculture will prosper and up-lift 70% of the total population that is annually growing by 3%. The total area of Pakistan is 197.7 MA (79.6 Mha). Out of which about 103.2 MA (41.77 Mha) comprises of rugged mountains, narrow valleys and foot hills, the remaining area of 93.5 MA (37.83 Mha) consists about 54.6 MA (22.1 Mha) is currently cultivated. Remaining 22.5 MA (9.1 Mha) is lying barren lacking water for irrigation. The total surface water availability is 154.5 MAF. Population density is the highest in the canal irrigated areas in the north east of Indus Plains. The increasing population and the associated social, technical and economic activities all depend, directly or indirectly, on the exploitation of water-as a resource. The total surface water availability is 154.5 MAF. Presently water diverted at canal heads is 106 MAF. In Vision 2025 Programme WAPDA has identified to build water sector and hydropower projects such as: i) Water Sector Projects (Gomal Zam, Mirani, Raised Mangla, Satpara. Kurram Tangi Dams and Greater Thai, Kachhi and Rainee Canals) and ii) Hydropower Projects (Jinnah Barrage, Allai Khwar, Khan Khwar, Duber Khwar, Golen Gole, Neelum Jhelum and Low Head Hydropower Project). Besides the above some more projects are under various stages of planning i.e.; (i) Basha Diamer Dam Project - Feasibility Detailed Design and Tenders, (ii) Akhori Dam Project - Feasibility, (iii) Sehwan Barrage - Feasibility. (iv) Chashma Right Bank Canal Lift Scheme Feasibility and Design, (v) Bunji Hydropower Project Pre-feasibility, (vi) Dasu Hydropower Project - Pre-feasibility and Skardu Dam - Prefeasibility. While, keeping in view the planning and development activities regarding water sector and hydropower projects, the country will

  6. Hydrological impacts of global land cover change and human water use

    Directory of Open Access Journals (Sweden)

    J. H. C. Bosmans

    2017-11-01

    Full Text Available Human impacts on global terrestrial hydrology have been accelerating during the 20th century. These human impacts include the effects of reservoir building and human water use, as well as land cover change. To date, many global studies have focussed on human water use, but only a few focus on or include the impact of land cover change. Here we use PCR-GLOBWB, a combined global hydrological and water resources model, to assess the impacts of land cover change as well as human water use globally in different climatic zones. Our results show that land cover change has a strong effect on the global hydrological cycle, on the same order of magnitude as the effect of human water use (applying irrigation, abstracting water, for industrial use for example, including reservoirs, etc.. When globally averaged, changing the land cover from that of 1850 to that of 2000 increases discharge through reduced evapotranspiration. The effect of land cover change shows large spatial variability in magnitude and sign of change depending on, for example, the specific land cover change and climate zone. Overall, land cover effects on evapotranspiration are largest for the transition of tall natural vegetation to crops in energy-limited equatorial and warm temperate regions. In contrast, the inclusion of irrigation, water abstraction and reservoirs reduces global discharge through enhanced evaporation over irrigated areas and reservoirs as well as through water consumption. Hence, in some areas land cover change and water distribution both reduce discharge, while in other areas the effects may partly cancel out. The relative importance of both types of impacts varies spatially across climatic zones. From this study we conclude that land cover change needs to be considered when studying anthropogenic impacts on water resources.

  7. Securing a better future for all: Nuclear techniques for global development and environmental protection. NA factsheet on isotope hydrology: Ensuring water now and for the future

    International Nuclear Information System (INIS)

    2012-01-01

    Providing adequate freshwater of a desired quality to their populations is one of the foremost development challenges faced by Member States. Although water is a basic human need, it is estimated that nearly one billion people in developing countries do not have access to safe drinking water and more than two billion lack basic sanitation facilities due to inadequate water availability. According to the World Health Organization, nearly five million people - mostly children - die each year from preventable, water-borne diseases. Increasing population, irrigated agriculture and industrial growth together have stressed global freshwater resources over the past several decades. In addition, climate change and the need for greater energy production are now significant drivers of stress on water resources. Nearly 40% of world food production is achieved by means of irrigated agriculture, which accounts for about 70% of total freshwater withdrawals. A significant proportion of groundwater used for irrigation comes from fossil or non-renewable sources, making the food supply unsustainable for a growing human population. Nearly one in three people depends upon water from rivers that are fed by glaciers and snow melt. Increased variability and vulnerability of river flows in a warmer climate (due to increased glacial melt and changes in precipitation patterns) will drive the need for changes in water use and management practices. These changes may also include greater dependence on already stressed groundwater resources. Nearly four billion people - half of the world's population - may live under conditions of water stress in the next two decades.

  8. GFDL CM2.1 Global Coupled Ocean-Atmosphere Model Water ...

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. GFDL CM2.1 Global Coupled Ocean-Atmosphere Model Water Hosing Experiment with 1 Sv equivalent of Freshening Control Expt: 100 yrs After Hosing: 300 yrs.

  9. SUNLIT AND SHADED MAIZE CANOPY WATER LOSS UNDER VARIED WATER STRESS

    Directory of Open Access Journals (Sweden)

    Antonio Odair Santos

    1999-12-01

    Full Text Available ABSTRACT The precise estimation of transpiration from plant canopies is important for the monitoring of crop water use and management of many agricultural operations related to water use planning. The aim of this study was to estimate transpiration from sunlit and shaded fractions of a maize ( Zea mays L. canopy, using the Penman-Monteith energy balance equation with modifications introduced by Fuchs et al. (1987 and Fuchs & Cohen (1989. Estimated values were validated by a heat pulse system, which was used to measure stem sap flow and by a weighing lysimeter. A relationship between incident radiation and leaf stomatal conductance for critical levels of leaf water potential was used to estimate transpiration. Results showed that computed transpiration of the shaded canopy ranged from 27 to 45% of the total transpiration when fluctuations in atmospheric demand and the level of water stress were taken in account. Hourly and daily estimates of transpiration showed agreement with lysimeter and heat pulse measurements on the well-watered plots. For the water-limited plots the precision of the estimate decreased due to difficulties in simulating the canopy stomatal conductance.

  10. Assessing the impacts of global change on water quantity and quality

    OpenAIRE

    Malsy, Marcus

    2016-01-01

    Water resources in the semi-arid to arid areas of Central Asia are often limited by low precipitation, and hence vulnerable to impacts of global change, i.e. socio-economic development and climate change. Both, socio-economic development and climate change are very likely causing significant changes as water resources are affected by two main effects: Firstly, growing population and industrial activities in the region raise the pressure on water resources due to increasing water abstractions....

  11. Global Anthropogenic Phosphorus Loads to Freshwater and Associated Grey Water Footprints and Water Pollution Levels: A High-Resolution Global Study

    Science.gov (United States)

    Mekonnen, Mesfin M.; Hoekstra, Arjen Y.

    2018-01-01

    We estimate the global anthropogenic phosphorus (P) loads to freshwater and the associated grey water footprints (GWFs) for the period 2002-2010, at a spatial resolution of 5 × 5 arc min, and compare the GWF per river basin to runoff to assess the P-related water pollution level (WPL). The global anthropogenic P load to freshwater systems from both diffuse and point sources is estimated at 1.5 Tg/yr. More than half of this total load was in Asia, followed by Europe (19%) and Latin America and the Caribbean (13%). The domestic sector contributed 54% to the total, agriculture 38%, and industry 8%. In agriculture, cereals production had the largest contribution to the P load (31%), followed by fruits, vegetables, and oil crops, each contributing 15%. The global total GWF related to anthropogenic P loads is estimated to be 147 × 1012 m3/yr, with China contributing 30%, India 8%, USA 7%, and Spain and Brazil 6% each. The basins with WPL > 1 (where GWF exceeds the basin's assimilation capacity) together cover about 38% of the global land area, 37% of the global river discharge, and provide residence to about 90% of the global population.

  12. Infrared thermometry and the crop water stress index. I. History, theory, and baselines

    International Nuclear Information System (INIS)

    Gardner, B.R.; Nielsen, D.C.; Shock, C.C.

    1992-01-01

    Development of portable infrared thermometers and the definition of the Crop Water Stress Index (CWSI) have led to widespread interest in infrared thermometry to monitor water stress and schedule irrigations. But the CWSI concept is still new and poorly understood by many. The purpose of this paper is to review the definition of CWSI, and the determination and interpretation of the non-water-stressed baselines used to compute CWSI. The non-water-stressed baseline equation normalizes the canopy minus air temperature differential for variations in vapor pressure deficit. Non-water-stressed baselines can be determined empirically from measurements of canopy and air temperatures and vapor pressure deficit, made diurnally on a single day, or at a single time of day over many days, on well-watered plants. The value of the maximum canopy minus air temperature differential under maximum water stress should also be determined empirically. Causes for CWSI values falling outside of the defined 0 to 10 unit range are reviewed. Non-water-stressed baselines may shift with plant growth stage. Effective use of CWSI is dependent on understanding the definition of CWSI, and the proper determination and use of non-water-stressed baselines. (author)

  13. Maintenance of water uptake and reduced water loss contribute to water stress tolerance of Spiraea alba Du Roi and Spiraea tomentosa L.

    Science.gov (United States)

    Stanton, Kelly M; Mickelbart, Michael V

    2014-01-01

    Two primarily eastern US native shrubs, Spiraea alba Du Roi and Spiraea tomentosa L., are typically found growing in wet areas, often with standing water. Both species have potential for use in the landscape, but little is known of their environmental requirements, including their adaptation to water stress. Two geographic accessions of each species were evaluated for their response to water stress under greenhouse conditions. Above-ground biomass, water relations and gas exchange were measured in well-watered and water stress treatments. In both species, water stress resulted in reduced growth, transpiration and pre-dawn water potential. However, both species also exhibited the ability to osmotically adjust to lower soil water content, resulting in maintained midday leaf turgor potential in all accessions. Net CO2 assimilation was reduced only in one accession of S. alba, primarily due to large reductions in stomatal conductance. S. tomentosa lost a larger proportion of leaves than S. alba in response to water stress. The primary water stress tolerance strategies of S. alba and S. tomentosa appear to be the maintenance of water uptake and reduced water loss.

  14. A new approach to inventorying bodies of water, from local to global scale

    Directory of Open Access Journals (Sweden)

    Bartout, Pascal

    2015-12-01

    Full Text Available Having reliable estimates of the number of water bodies on different geographical scales is of great importance to better understand biogeochemical cycles and to tackle the social issues related to the economic and cultural use of water bodies. However, limnological research suffers from a lack of reliable inventories; the available scientific references are predominately based on water bodies of natural origin, large in size and preferentially located in previously glaciated areas. Artificial, small and randomly distributed water bodies, especially ponds, are usually not inventoried. Following Wetzel’s theory (1990, some authors included them in global inventories by using remote sensing or mathematical extrapolation, but fieldwork on the ground has been done on a very limited amount of territory. These studies have resulted in an explosive increase in the estimated number of water bodies, going from 8.44 million lakes (Meybeck 1995 to 3.5 billion water bodies (Downing 2010. These numbers raise several questions, especially about the methodology used for counting small-sized water bodies and the methodological treatment of spatial variables. In this study, we use inventories of water bodies for Sweden, Finland, Estonia and France to show incoherencies generated by the “global to local” approach. We demonstrate that one universal relationship does not suffice for generating the regional or global inventories of water bodies because local conditions vary greatly from one region to another and cannot be offset adequately by each other. The current paradigm for global estimates of water bodies in limnology, which is based on one representative model applied to different territories, does not produce sufficiently exact global inventories. The step-wise progression from the local to the global scale requires the development of many regional equations based on fieldwork; a specific equation that adequately reflects the actual relationship

  15. Global LC/MS Metabolomics Profiling of Calcium Stressed and Immunosuppressant Drug Treated Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Stefan Jenkins

    2013-12-01

    Full Text Available Previous studies have shown that calcium stressed Saccharomyces cerevisiae, challenged with immunosuppressant drugs FK506 and Cyclosporin A, responds with comprehensive gene expression changes and attenuation of the generalized calcium stress response. Here, we describe a global metabolomics workflow for investigating the utility of tracking corresponding phenotypic changes. This was achieved by efficiently analyzing relative abundance differences between intracellular metabolite pools from wild-type and calcium stressed cultures, with and without prior immunosuppressant drugs exposure. We used pathway database content from WikiPathways and YeastCyc to facilitate the projection of our metabolomics profiling results onto biological pathways. A key challenge was to increase the coverage of the detected metabolites. This was achieved by applying both reverse phase (RP and aqueous normal phase (ANP chromatographic separations, as well as electrospray ionization (ESI and atmospheric pressure chemical ionization (APCI sources for detection in both ion polarities. Unsupervised principle component analysis (PCA and ANOVA results revealed differentiation between wild-type controls, calcium stressed and immunosuppressant/calcium challenged cells. Untargeted data mining resulted in 247 differentially expressed, annotated metabolites, across at least one pair of conditions. A separate, targeted data mining strategy identified 187 differential, annotated metabolites. All annotated metabolites were subsequently mapped onto curated pathways from YeastCyc and WikiPathways for interactive pathway analysis and visualization. Dozens of pathways showed differential responses to stress conditions based on one or more matches to the list of annotated metabolites or to metabolites that had been identified further by MS/MS. The purine salvage, pantothenate and sulfur amino acid pathways were flagged as being enriched, which is consistent with previously published

  16. Global Plant Stress Signaling: Reactive Oxygen Species at the Cross-Road

    Directory of Open Access Journals (Sweden)

    Nasser eSewelam

    2016-02-01

    Full Text Available Current technologies have changed biology into a data-intensive field and significantly increased our understanding of signal transduction pathways in plants. However, global defense signaling networks in plants have not been established yet. Considering the apparent intricate nature of signaling mechanisms in plants (due to their sessile nature, studying the points at which different signaling pathways converge, rather than the branches, represents a good start to unravel global plant signaling networks. In this regard, growing evidence shows that the generation of reactive oxygen species (ROS is one of the most common plant responses to different stresses, representing a point at which various signaling pathways come together. In this review, the complex nature of plant stress signaling networks will be discussed. An emphasis on different signaling players with a specific attention to ROS as the primary source of the signaling battery in plants will be presented. The interactions between ROS and other signaling components, e.g. calcium, redox homeostasis, membranes, G-proteins, MAPKs, plant hormones and transcription factors will be assessed. A better understanding of the vital roles ROS are playing in plant signaling would help innovate new strategies to improve plant productivity under the circumstances of the increasing severity of environmental conditions and the high demand of food and energy worldwide

  17. Longevity of animals under reactive oxygen species stress and disease susceptibility due to global warming

    Science.gov (United States)

    Paital, Biswaranjan; Panda, Sumana Kumari; Hati, Akshaya Kumar; Mohanty, Bobllina; Mohapatra, Manoj Kumar; Kanungo, Shyama; Chainy, Gagan Bihari Nityananda

    2016-01-01

    The world is projected to experience an approximate doubling of atmospheric CO2 concentration in the next decades. Rise in atmospheric CO2 level as one of the most important reasons is expected to contribute to raise the mean global temperature 1.4 °C-5.8 °C by that time. A survey from 128 countries speculates that global warming is primarily due to increase in atmospheric CO2 level that is produced mainly by anthropogenic activities. Exposure of animals to high environmental temperatures is mostly accompanied by unwanted acceleration of certain biochemical pathways in their cells. One of such examples is augmentation in generation of reactive oxygen species (ROS) and subsequent increase in oxidation of lipids, proteins and nucleic acids by ROS. Increase in oxidation of biomolecules leads to a state called as oxidative stress (OS). Finally, the increase in OS condition induces abnormality in physiology of animals under elevated temperature. Exposure of animals to rise in habitat temperature is found to boost the metabolism of animals and a very strong and positive correlation exists between metabolism and levels of ROS and OS. Continuous induction of OS is negatively correlated with survivability and longevity and positively correlated with ageing in animals. Thus, it can be predicted that continuous exposure of animals to acute or gradual rise in habitat temperature due to global warming may induce OS, reduced survivability and longevity in animals in general and poikilotherms in particular. A positive correlation between metabolism and temperature in general and altered O2 consumption at elevated temperature in particular could also increase the risk of experiencing OS in homeotherms. Effects of global warming on longevity of animals through increased risk of protein misfolding and disease susceptibility due to OS as the cause or effects or both also cannot be ignored. Therefore, understanding the physiological impacts of global warming in relation to

  18. Longevity of animals under reactive oxygen species stress and disease susceptibility due to global warming.

    Science.gov (United States)

    Paital, Biswaranjan; Panda, Sumana Kumari; Hati, Akshaya Kumar; Mohanty, Bobllina; Mohapatra, Manoj Kumar; Kanungo, Shyama; Chainy, Gagan Bihari Nityananda

    2016-02-26

    The world is projected to experience an approximate doubling of atmospheric CO2 concentration in the next decades. Rise in atmospheric CO2 level as one of the most important reasons is expected to contribute to raise the mean global temperature 1.4 °C-5.8 °C by that time. A survey from 128 countries speculates that global warming is primarily due to increase in atmospheric CO2 level that is produced mainly by anthropogenic activities. Exposure of animals to high environmental temperatures is mostly accompanied by unwanted acceleration of certain biochemical pathways in their cells. One of such examples is augmentation in generation of reactive oxygen species (ROS) and subsequent increase in oxidation of lipids, proteins and nucleic acids by ROS. Increase in oxidation of biomolecules leads to a state called as oxidative stress (OS). Finally, the increase in OS condition induces abnormality in physiology of animals under elevated temperature. Exposure of animals to rise in habitat temperature is found to boost the metabolism of animals and a very strong and positive correlation exists between metabolism and levels of ROS and OS. Continuous induction of OS is negatively correlated with survivability and longevity and positively correlated with ageing in animals. Thus, it can be predicted that continuous exposure of animals to acute or gradual rise in habitat temperature due to global warming may induce OS, reduced survivability and longevity in animals in general and poikilotherms in particular. A positive correlation between metabolism and temperature in general and altered O2 consumption at elevated temperature in particular could also increase the risk of experiencing OS in homeotherms. Effects of global warming on longevity of animals through increased risk of protein misfolding and disease susceptibility due to OS as the cause or effects or both also cannot be ignored. Therefore, understanding the physiological impacts of global warming in relation to

  19. High water-stressed population estimated by world water resources assessment including human activities under SRES scenarios

    Science.gov (United States)

    Kiguchi, M.; Shen, Y.; Kanae, S.; Oki, T.

    2009-04-01

    In an argument of the reduction and the adaptation for the climate change, the evaluation of the influence by the climate change is important. When we argue in adaptation plan from a damage scale and balance with the cost, it is particularly important. Parry et al (2001) evaluated the risks in shortage of water, malaria, food, the risk of the coast flood by temperature function and clarified the level of critical climate change. According to their evaluation, the population to be affected by the shortage of water suddenly increases in the range where temperature increases from 1.5 to 2.0 degree in 2080s. They showed how much we need to reduce emissions in order to draw-down significantly the number at risk. This evaluation of critical climate change threats and targets of water shortage did not include the water withdrawal divided by water availability. Shen et al (2008a) estimated the water withdrawal of projection of future world water resources according to socio-economic driving factors predicted for scenarios A1b, A2, B1, and B2 of the Special Report on Emission Scenarios (SRES). However, these results were in function of not temperature but time. The assessment of the highly water-stressed population considered the socioeconomic development is necessary for a function of the temperature. Because of it is easy to understand to need to reduce emission. We present a multi-GCM analysis of the global and regional populations lived in highly water-stressed basin for a function of the temperature using the socioeconomic data and the outputs of GCMs. In scenario A2, the population increases gradually with warming. On the other hand, the future projection population in scenario A1b and B1 increase gradually until the temperature anomaly exceeds around from +1 to +1.5 degree. After that the population is almost constant. From Shen et al (2008b), we evaluated the HWSP and its ratio in the world with temperature function for scenarios A1B, A2, and B1 by the index of W

  20. Closing the 21st century global water gap: costs and effectiveness of adaptation measures

    Science.gov (United States)

    Bierkens, M. F.; Droogers, P.; Hunink, J.; Buitink, J.; Sutanudjaja, E.; Karssenberg, D.; Van Beek, L. P.; Straatsma, M. W.

    2017-12-01

    Water scarcity affects a major part of the globe, and is expected to increase significantly until 2100 as a result of climate change and socioeconomic developments. Yet, global projections are unavailable on the effectiveness and costs of adaptation measures to close the future water gap under global change. Here, we present a 21st century projection of the closure of the water gap under two contrasting climate and socio-economic scenarios: RCP2.6/SSP1(s1) and RCP8.5/SSP5(s5). We coupled a global hydrological model to water demand and redistribution model, and forced them with five General Circulation Models (GCMs) to assess the future water gap for 1604 water provinces covering most of the global land mass. Subsequently, using so-called water availability cost curves, we determined the water gap reduction that could be achieved by increasingly aggressive and expensive sets of adaptation measures, respectively aimed at improving agriculture, increasing water supply, and reducing water demands. Our results show that for s1, the water gap peaks around 2050 and declines towards 2100. Contrastingly, for s5, the gap increases linearly. Hotspots in water scarcity are found in the USA, India, and China. The proposed adaptation sets reduce the water gap, but for the majority of the hotspots are not sufficient to close the water gap completely. The median annual adaptation costs for the proposed measures amount to less than 2% of the GDP of the affected water provinces. Although these costs are already substantial, they do leave room for additional unorthodox adaptation measures.

  1. Ultraviolet-B and water stress effects on growth, gas exchange and oxidative stress in sunflower plants.

    Science.gov (United States)

    Cechin, Inês; Corniani, Natália; de Fátima Fumis, Terezinha; Cataneo, Ana Catarina

    2008-07-01

    The effects and interaction of drought and UV-B radiation were studied in sunflower plants (Helianthus annuus L. var. Catissol-01), growing in a greenhouse under natural photoperiod conditions. The plants received approximately 1.7 W m(-2) (controls) or 8.6 W m(-2) (+UV-B) of UV-B radiation for 7 h per day. The UV-B and water stress treatments started 18 days after sowing. After a period of 12 days of stress, half of the water-stressed plants (including both UV-B irradiated or non-irradiated) were rehydrated. Both drought and UV-B radiation treatments resulted in lower shoot dry matter per plant, but there was no significant interaction between the two treatments. Water stress and UV-B radiation reduced photosynthesis, stomatal conductance and transpiration. However, the amplitude of the effects of both stressors was dependent on the interactions. This resulted in alleviation of the negative effect of drought on photosynthesis and transpiration by UV-B radiation as the water stress intensified. Intercelluar CO(2) concentration was initially reduced in all treatments compared to control plants but it increased with time. Photosynthetic pigments were not affected by UV-B radiation. Water stress reduced photosynthetic pigments only under high UV-B radiation. The decrease was more accentuated for chlorophyll a than for chlorophyll b. As a measure for the maximum efficiency of photosystem II in darkness F (v)/F (m) was used, which was not affected by drought stress but initially reduced by UV-B radiation. Independent of water supply, UV-B radiation increased the activity of pirogalol peroxidase and did not increase the level of malondialdehyde. On the other hand, water stress did not alter the activity of pirogalol peroxidase and caused membrane damage as assessed by lipid peroxidation. The application of UV-B radiation together with drought seemed to have a protective effect by lowering the intensity of lipid peroxidation caused by water stress. The content of proline

  2. The global dimension of water governance: Nine reasons for global arrangements in order to cope with local water problems

    NARCIS (Netherlands)

    Hoekstra, Arjen Ysbert

    2006-01-01

    Where water problems extend beyond the borders of local communities, the catchment area or river basin is generally seen as the most appropriate unit for analysis, planning and institutional arrangements. In this paper it is argued that addressing water problems at the river basin level is not

  3. Global assessment of predictability of water availability: A bivariate probabilistic Budyko analysis

    Science.gov (United States)

    Wang, Weiguang; Fu, Jianyu

    2018-02-01

    Estimating continental water availability is of great importance for water resources management, in terms of maintaining ecosystem integrity and sustaining society development. To more accurately quantify the predictability of water availability, on the basis of univariate probabilistic Budyko framework, a bivariate probabilistic Budyko approach was developed using copula-based joint distribution model for considering the dependence between parameter ω of Wang-Tang's equation and the Normalized Difference Vegetation Index (NDVI), and was applied globally. The results indicate the predictive performance in global water availability is conditional on the climatic condition. In comparison with simple univariate distribution, the bivariate one produces the lower interquartile range under the same global dataset, especially in the regions with higher NDVI values, highlighting the importance of developing the joint distribution by taking into account the dependence structure of parameter ω and NDVI, which can provide more accurate probabilistic evaluation of water availability.

  4. Global land-water nexus: Agricultural land and freshwater use embodied in worldwide supply chains.

    Science.gov (United States)

    Chen, B; Han, M Y; Peng, K; Zhou, S L; Shao, L; Wu, X F; Wei, W D; Liu, S Y; Li, Z; Li, J S; Chen, G Q

    2018-02-01

    As agricultural land and freshwater inextricably interrelate and interact with each other, the conventional water and land policy in "silos" should give way to nexus thinking when formulating the land and water management strategies. This study constructs a systems multi-regional input-output (MRIO) model to expound global land-water nexus by simultaneously tracking agricultural land and freshwater use flows along the global supply chains. Furthermore, land productivity and irrigation water requirements of 160 crops in different regions are investigated to reflect the land-water linkage. Results show that developed economies (e.g., USA and Japan) and major large developing economies (e.g., mainland China and India) are the overriding drivers of agricultural land and freshwater use globally. In general, significant net transfers of these two resources are identified from resource-rich and less-developed economies to resource-poor and more-developed economies. For some crops, blue water productivity is inversely related to land productivity, indicating that irrigation water consumption is sometimes at odds with land use. The results could stimulus international cooperation for sustainable land and freshwater management targeting on original suppliers and final consumers along the global supply chains. Moreover, crop-specific land-water linkage could provide insights for trade-off decisions on minimizing the environmental impacts on local land and water resources. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Water Stress on U.S. Power Production at Decadal Time Horizons

    Energy Technology Data Exchange (ETDEWEB)

    Ganguly, Auroop R. [Northeastern Univ., Boston, MA (United States). Sustainability and Data Sciences Lab.. Civil and Environmental Engineering Dept.; Ganguli, Poulomi [Northeastern Univ., Boston, MA (United States). Sustainability and Data Sciences Lab.; Kumar, Devashish [Northeastern Univ., Boston, MA (United States). Sustainability and Data Sciences Lab.

    2014-09-01

    Thermoelectric power production at risk, owing to current and projected water scarcity and rising stream temperatures, is assessed for the contiguous United States at decadal scales. Regional water scarcity is driven by climate variability and change, as well as by multi-sector water demand. While a planning horizon of zero to about thirty years is occasionally prescribed by stakeholders, the challenges to risk assessment at these scales include the difficulty in delineating decadal climate trends from intrinsic natural or multiple model variability. Current generation global climate or earth system models are not credible at the spatial resolutions of power plants, especially for surface water quantity and stream temperatures, which further exacerbates the assessment challenge. Population changes, which are difficult to project, cannot serve as adequate proxies for changes in the water demand across sectors. The hypothesis that robust assessments of power production at risk are possible, despite the uncertainties, has been examined as a proof of concept. An approach is presented for delineating water scarcity and temperature from climate models, observations and population storylines, as well as for assessing power production at risk by examining geospatial correlations of power plant locations within regions where the usable water supply for energy production happens to be scarcer and warmer. Our analyses showed that in the near term, more than 200 counties are likely to be exposed to water scarcity in the next three decades. Further, we noticed that stream gauges in more than five counties in the 2030s and ten counties in the 2040s showed a significant increase in water temperature, which exceeded the power plant effluent temperature threshold set by the EPA. Power plants in South Carolina, Louisiana, and Texas are likely to be vulnerable owing to climate driven water stresses. In all, our analysis suggests that under various combinations of plausible climate

  6. Surface water change as a significant contributor to global evapotranspiration change

    Science.gov (United States)

    Zhan, S.; Song, C.

    2017-12-01

    Water comprises a critical component of global/regional hydrological and biogeochemical cycles and is essential to all organisms including humans. In the past several decades, climate change has intensified the hydrological cycle, with significant implications for ecosystem services and feedback to regional and global climate. Evapotranspiration (ET) as a linking mechanism between land surface and atmosphere is central to the water cycle and an excellent indicator of the intensity of water cycle. Knowledge of the temporal changes of ET is crucial for accurately estimating global or regional water budgets and better understanding climate and hydrological interactions. While studies have examined changes in global ET, they were conducted using a constant land and surface water (SW) area. However, as many studies have found that global SW is very dynamic and their surface areas have generally been increasing since the 1980s. The conversion from land to water and vice versa significantly changes the local ET since water bodies evaporate at a rate that can be much higher than that of the land. Here, we quantify the global changes in ET caused by such land-water conversion using remotely-sensed SW area and various ET and potential ET products. New SW and lost SW between circa-1985 and circa-2015 were derived from remote sensing and were used to modify the local ET estimates. We found an increase in ET in all continents as consistent with the net increase in SW area. The increasing SW area lead to a global increase in ET by 30.38 ± 5.28 km3/yr. This is a significant contribution when compared to the 92.95 km3/yr/yr increase in ET between 1982-1997 and 103.43 km3/yr/yr decrease between 1998-2008 by Jung et al., (2010) assuming a constant SW. The results enhance our understanding of the water fluxes between the land and atmosphere and supplement land water budget estimates. We conclude that changes in SW lead to a significant change in global ET that cannot be neglected in

  7. NEWS Climatology Project: The State of the Water Cycle at Continental to Global Scales

    Science.gov (United States)

    Rodell, Matthew; LEcuyer, Tristan; Beaudoing, Hiroko Kato; Olson, Bill

    2011-01-01

    NASA's Energy and Water Cycle Study (NEWS) program fosters collaborative research towards improved quantification and prediction of water and energy cycle consequences of climate change. In order to measure change, it is first necessary to describe current conditions. The goal of the NEWS Water and Energy Cycle Climatology project is to develop "state of the global water cycle" and "state of the global energy cycle" assessments based on data from modern ground and space based observing systems and data integrating models. The project is a multiinstitutional collaboration with more than 20 active contributors. This presentation will describe results of the first stage of the water budget analysis, whose goal was to characterize the current state of the water cycle on mean monthly, continental scales. We examine our success in closing the water budget within the expected uncertainty range and the effects of forcing budget closure as a method for refining individual flux estimates.

  8. Estimating anthropogenic ecological water stress in the US great lakes region

    Science.gov (United States)

    Anthropocentric water resources management that prioritizes socio-economic growth can cause harmful ecological water stress by depriving aquatic ecosystems of the water needed to sustain habitats. It is important to better understand the impacts of water withdrawal by different economic sectors (e.g...

  9. Spinach biomass yield and physiological response to interactive salinity and water stress

    Science.gov (United States)

    Critical shortages of fresh water throughout arid regions means that growers must face the choice of applying insufficient fresh water, applying saline water, or consider the option of combined water and salt stress. The best approach to manage drought and salinity is evaluation of the impact of wat...

  10. Global analysis of epigenetic regulation of gene expression in response to drought stress in Sorghum.

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, Anireddy [Colorado State Univ., Fort Collins, CO (United States); Ben-Hur, Asa [Colorado State Univ., Fort Collins, CO (United States)

    2017-11-22

    Abiotic stresses including drought are major limiting factors of crop yields and cause significant crop losses. Acquisition of stress tolerance to abiotic stresses requires coordinated regulation of a multitude of biochemical and physiological changes, and most of these changes depend on alterations in gene expression. The goal of this work is to perform global analysis of differential regulation of gene expression and alternative splicing, and their relationship with chromatin landscape in drought sensitive and tolerant cultivars. our Iso-Seq study revealed transcriptome-wide full-length isoforms at an unprecedented scale with over 11000 novel splice isoforms. Additionally, we uncovered alternative polyadenylation sites of ~11000 expressed genes and many novel genes. Overall, Iso-Seq results greatly enhanced sorghum gene annotations that are not only useful in analyzing all our RNA-seq, ChIP-seq and ATAC-seq data but also serve as a great resource to the plant biology community. Our studies identified differentially expressed genes and splicing events that are correlated with the drought-resistant phenotype. An association between alternative splicing and chromatin accessibility was also revealed. Several computational tools developed here (TAPIS and iDiffIR) have been made freely available to the research community in analyzing alternative splicing and differential alternative splicing.

  11. Optimization of Water Allocation between Different Crops in Water Stress Conditions in Qazvin Irrigation Network

    Directory of Open Access Journals (Sweden)

    Mehdi Mohammad khani

    2017-06-01

    minimum productivity index. Therefore, in water deficit conditions, the priority of water distribution in all options is for tomatoes and the last priority for sugar beets. In all of the options, wheat, barley and canola ascend in productivity index and corn and sugar beets descend in productivity index. Conclusion: Studying water- production index shows that considering instructions will result in optimal productivity that in turn will increase production and network total income. Optimal model results show that drought effects can be satisfied with optimal and targeted management in allocating water, so that network total income has not reduced in stress occurrences compared to network net income. Optimization method in model development has been selected according to aim of model and it is proposed that model results to be assessed by non- linear optimization methods. It is proposed that, different scenarios of climate are studied in region according to climate changes and optimal allocation of water is prepared according to the effect of these scenarios on temperature increase, raining decrease and products water need increase in present cultivation method. For model efficiency increase, it is proposed that using neural networks capabilities, intelligent prediction of the input discharge to the network is done and the possibility of comprehensive management and timely combining of network with water allocation optimal model is provided.

  12. Tree die-off in response to global change-type drought: Mortality insights from a decade of plant water potential measurements

    Science.gov (United States)

    Breshears, D.D.; Myers, O.B.; Meyer, Clifton W.; Barnes, F.J.; Zou, C.B.; Allen, Craig D.; McDowell, N.G.; Pockman, W. T.

    2009-01-01

    Global climate change is projected to produce warmer, longer, and more frequent droughts, referred to here as “global change-type droughts”, which have the potential to trigger widespread tree die-off. However, drought-induced tree mortality cannot be predicted with confidence, because long-term field observations of plant water stress prior to, and culminating in, mortality are rare, precluding the development and testing of mechanisms. Here, we document plant water stress in two widely distributed, co-occurring species, piñon pine (Pinus edulis) and juniper (Juniperus monosperma), over more than a decade, leading up to regional-scale die-off of piñon pine trees in response to global change-related drought. Piñon leaf water potentials remained substantially below their zero carbon assimilation point for at least 10 months prior to dying, in contrast to those of juniper, which rarely dropped below their zero-assimilation point. These data suggest that piñon mortality was driven by protracted water stress, leading to carbon starvation and associated increases in susceptibility to other disturbances (eg bark beetles), a finding that should help to improve predictions of mortality during drought.

  13. Nitrogen accumulation in lucerne (Medicago sativa L. under water deficit stress

    Directory of Open Access Journals (Sweden)

    Vasileva Viliana

    2013-01-01

    Full Text Available In order to study nitrogen accumulation in aboveground and root dry mass in lucerne (Medicago sativa L. under water deficit stress, a pot experiment was carried out at the Institute of Forage Crops, Pleven, Bulgaria. The plants were grown under optimum water supply (75-80% FC and 10-days water deficit stress was simulated at the stage of budding by interrupting the irrigation until soil moisture was reduced to 37-40% FC. Mineral nitrogen fertilization (ammonium nitrate at the doses of 40, 80, 120 and 160 mg N kg-1 soil was applied. It was found that nitrogen accumulation in dry aboveground mass was reduced to 18.0%, and in dry root mass to 26.5% under water deficit stress. Mineral nitrogen fertilization contributed to easily overcome the stress conditions of water deficit stress in lucerne.

  14. Germination sensitivity to water stress in four shrubby species across the Mediterranean Basin.

    Science.gov (United States)

    Chamorro, D; Luna, B; Ourcival, J-M; Kavgacı, A; Sirca, C; Mouillot, F; Arianoutsou, M; Moreno, J M

    2017-01-01

    Mediterranean shrublands are generally water-limited and fire-driven ecosystems. Seed-based post-fire regeneration may be affected by varying rainfall patterns, depending on species sensitivity to germinate under water stress. In our study, we considered the germination response to water stress in four species from several sites across the Mediterranean Basin. Seeds of species with a hard coat (Cistus monspeliensis, C. salviifolius, Cistaceae, Calicotome villosa, Fabaceae) or soft coat (Erica arborea, Ericaceae), which were exposed or not to a heat shock and smoke (fire cues), were made to germinate under water stress. Final germination percentage, germination speed and viability of seeds were recorded. Germination was modelled using hydrotime analysis and correlated to the water balance characteristics of seed provenance. Water stress was found to decrease final germination in the three hard-seeded species, as well as reduce germination speed. Moreover, an interaction between fire cues and water stress was found, whereby fire cues increased sensitivity to water stress. Seed viability after germination under water stress also declined in two hard-seeded species. Conversely, E. arborea showed little sensitivity to water stress, independent of fire cues. Germination responses varied among populations of all species, and hydrotime parameters were not correlated to site water balance, except in E. arborea when not exposed to fire cues. In conclusion, the species studied differed in germination sensitivity to water stress; furthermore, fire cues increased this sensitivity in the three hard-seeded species, but not in E. arborea. Moreover, populations within species consistently differed among themselves, but these differences could only be related to the provenance locality in E. arborea in seeds not exposed to fire cues. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  15. Paraheliotropism can protect water-stressed bean (Phaseolus vulgaris L.) plants against photoinhibition.

    Science.gov (United States)

    Pastenes, Claudio; Porter, Victor; Baginsky, Cecilia; Horton, Peter; González, Javiera

    2004-12-01

    In order to estimate the importance of leaf movements on photosynthesis in well-watered and water-stressed field grown bean cultivars (Arroz Tuscola (AT), Orfeo INIA (OI), Bayos Titan (BT), and Hallados Dorado (HD)), CO2 assimilation, leaf temperature, and capacity for the maximum quantum yield recovery, measured as Fv/Fm, were assessed. Leaf water potential was lower in water-stressed compared to control plants throughout the day. Water status determined a decrease in the CO2 assimilation and stomatal conductance as light intensity and temperature increased up to maximal intensities at midday. Both parameters were lower in stressed compared to control plants. Even though high light intensity and water-stress induced stomatal closure is regarded as a photoinhibitory condition, the recovery of variable to maximal fluorescence (Fv/Fm) after 30min of darkness was nearly constant in both water regimes. In fact, higher values were observed in OI and AT when under stress. Photochemical and non-photochemical fluorescence quenching resulted in minor changes during the day and were similar between watered and stressed plants. It is concluded that paraheliotropism, present in the four bean cultivars, efficiently protects stressed plants from photoinhibition in the field and helps maintain leaf temperatures far below the ambient temperatures, however, it may also be responsible for low CO2 assimilation rates in watered plants.

  16. Electrochemical potential measurements in boiling water reactors; relation to water chemistry and stress corrosion

    International Nuclear Information System (INIS)

    Indig, M.E.; Cowan, R.L.

    1981-01-01

    Electrochemical potential measurements were performed in operating boiling water reactors to determine the range of corrosion potentials that exist from cold standby to full power operation and the relationship of these measurements to reactor water chemistry. Once the corrosion potentials were known, experiments were performed in the laboratory under electrochemical control to determine potentials and equivalent dissolved oxygen concentrations where intergranular stress corrosion cracking (IGSCC) would and would not occur on welded Type-304 stainless steel. At 274 0 C, cracking occurred at potentials that were equivalent to dissolved oxygen concentration > 40 to 50 ppb. With decreasing temperature, IGSCC became more difficult and only severely sensitized stainless steel would crack. Recent in-reactor experiments combined with the previous laboratory data, have shown that injection of small concentrations of hydrogen during reactor operation can cause a significant decrease in corrosion potential which should cause immunity to IGSCC. (author)

  17. Circuitry linking the global Csr and σE-dependent cell envelope stress response systems.

    Science.gov (United States)

    Yakhnin, Helen; Aichele, Robert; Ades, Sarah E; Romeo, Tony; Babitzke, Paul

    2017-09-18

    CsrA of Escherichia coli is an RNA-binding protein that globally regulates a wide variety of cellular processes and behaviors including carbon metabolism, motility, biofilm formation, and the stringent response. CsrB and CsrC are sRNAs that sequester CsrA, thereby preventing CsrA-mRNA interaction. RpoE (σ E ) is the extracytoplasmic stress response sigma factor of E. coli Previous RNA-seq studies identified rpoE mRNA as a CsrA target. Here we explored the regulation of rpoE by CsrA and found that CsrA represses rpoE translation. Gel mobility shift, footprint and toeprint studies identified three CsrA binding sites in the rpoE leader transcript, one of which overlaps the rpoE Shine-Dalgarno (SD) sequence, while another overlaps the rpoE translation initiation codon. Coupled in vitro transcription-translation experiments showed that CsrA represses rpoE translation by binding to these sites. We further demonstrate that σ E indirectly activates transcription of csrB and csrC , leading to increased sequestration of CsrA such that repression of rpoE by CsrA is reduced. We propose that the Csr system fine-tunes the σ E -dependent cell envelope stress response. We also identified a 51 amino acid coding sequence whose stop codon overlaps the rpoE start codon, and demonstrate that rpoE is translationally coupled with this upstream open reading frame (ORF51). Loss of coupling reduces rpoE translation by more than 50%. Identification of a translationally coupled ORF upstream of rpoE suggests that this previously unannotated protein may participate in the cell envelope stress response. In keeping with existing nomenclature, we name ORF51 as rseD , resulting in an operon arrangement of rseD-rpoE-rseA-rseB-rseC IMPORTANCE CsrA posttranscriptionally represses genes required for bacterial stress responses, including the stringent response, catabolite repression, and the RpoS (σ S )-mediated general stress response. We show that CsrA represses translation of rpoE , encoding the

  18. Modified Feddes type stress reduction function for modeling root water uptake: Accounting for limited aeration and low water potential

    Science.gov (United States)

    Peters, Andre; Durner, Wolfgang; Iden, Sascha C.

    2017-04-01

    Modeling water flow in the soil-plant-atmosphere continuum with the Richards equation requires a model for the sink term describing water uptake by plant roots. Despite recent progress in developing process-based models of water uptake by plant roots and water flow in aboveground parts of vegetation, effective models of root water uptake are widely applied and necessary for large-scale applications. Modeling root water uptake consists of three steps, (i) specification of the spatial distribution of potential uptake, (ii) reduction of uptake due to various stress sources, and (iii) enhancement of uptake in part of the simulation domain to describe compensation. We discuss the conceptual shortcomings of the frequently used root water uptake model of Feddes and suggest a simple but effective improvement of the model. The improved model parametrizes water stress in wet soil by a reduction scheme which is formulated as function of air content where water stress due to low soil water potential is described by the original approach of Feddes. The improved model is physically more consistent than Feddes' model because water uptake in wet soil is limited by aeration which is a function of water content. The suggested modification is particularly relevant for simulations in heterogeneous soils, because stress parameters are uniquely defined for the entire simulation domain, irrespective of soil texture. Numerical simulations of water flow and root water uptake in homogeneous and stochastic heterogeneous soils illustrate the effect of the new model on root water uptake and actual transpiration. For homogeneous fine-textured soils, root water uptake never achieves its potential rate. In stochastic heterogeneous soil, water uptake is more pronounced at the interfaces between fine and coarse regions which has potential implications for plant growth, nutrient uptake and depletion.

  19. The Water Quality in Rio Highlights the Global Public Health Concern Over Untreated Sewage Disposal

    Science.gov (United States)

    Water quality issues in Rio have been widely publicized because of the 2016 Olympics. Recent concerns about polluted waters that athletes may be exposed to highlights the conditions that more than a billion people globally are exposed to daily. Despite these unhealthy conditions,...

  20. Advances In Understanding Global Water Cycle With Advent of GPM Mission

    Science.gov (United States)

    Smith, Eric A.

    2002-01-01

    During the coming decade, the internationally organized Global Precipitation Measurement (GPM) Mission will take an important step in creating a global precipitation observing system from space based on an international fleet of satellites operated as a constellation. One perspective for understanding the nature of GPM is that it will be a hierarchical system of datastreams beginning with very high caliber combined dual frequency radar/passive microwave (PMW) rain-radiometer retrievals, to high caliber PMW rain-radiometer only retrievals, and then on to blends of the former datastreams with additional lower-caliber PMW-based and IR-based rain retrievals. Within the context of the now emerging global water & energy cycle (GWEC) programs of a number of research agencies throughout the world, GPM serves as a centerpiece space mission for improving our understanding of the Earth's water cycle from a global measurement perspective and on down to regional scales and below. One of the salient problems within our current understanding of the global water and energy cycle is determining whether a change in the rate of the water cycle is accompanying changes in climate, e.g., climate warming. As there are a number of ways in which to define a rate-change of the global water cycle, it is not entirely clear as to what constitutes such a determination. This paper first presents an overview of the GPM Mission and how its overriding scientific objectives for climate, weather, and hydrology flow from the anticipated improvements that are being planned for the constellation-based measuring system. Next, the paper shows how the GPM observations can be used within the framework of the oceanic and continental water budget equations to determine whether a given perturbation in precipitation is indicative of an actual rate change in the water cycle, consistent with required responses in water storage and/or water flux transport processes, or whether it is simply part of the natural

  1. Physiological behaviors and recovery responses of four Galician grapevine (Vitis vinifera L. ) cultivars under water stress

    OpenAIRE

    Islam, M.; Berrios, J.

    2012-01-01

    Gas exchange parameters and chlorophyll fluorescence of four pot grown Galician grapevines (Vitis vinifera L. cv. Albariño, Brancellao, Godello and Treixadura) were examined under different levels of water stress in greenhouse. After extreme stress, gas exchange recovery responses were evaluated. Average ΨPD for control and stressed plants were -0.4MPa and -1.45MPa respectively. All varieties showed gradual declining of all gas exchange parameters (gs, E and A) with increasing of stress perio...

  2. A Data Analysis Toolbox for Modeling the Global Food-Energy-Water Nexus

    Science.gov (United States)

    AghaKouchak, A.; Sadegh, M.; Mallakpour, I.

    2017-12-01

    Water, Food and energy systems are highly interconnected. More than seventy percent of global water resource is used for food production. Water withdrawal, purification, and transfer systems are energy intensive. Furthermore, energy generation strongly depends on water availability. Therefore, considering the interactions in the nexus of water, food and energy is crucial for sustainable management of available resources. In this presentation, we introduce a user-friendly data analysis toolbox that mines the available global data on food, energy and water, and analyzes their interactions. This toolbox provides estimates of water footprint for a wide range of food types in different countries and also approximates the required energy and water resources. The toolbox also provides estimates of the corresponding emissions and biofuel production of different crops. In summary, this toolbox allows evaluating dependencies of the food, energy, and water systems at the country scale. We present global analysis of the interactions between water, food and energy from different perspectives including efficiency and diversity of resources use.

  3. Sensitivity of Water Scarcity Events to ENSO-Driven Climate Variability at the Global Scale

    Science.gov (United States)

    Veldkamp, T. I. E.; Eisner, S.; Wada, Y.; Aerts, J. C. J. H.; Ward, P. J.

    2015-01-01

    Globally, freshwater shortage is one of the most dangerous risks for society. Changing hydro-climatic and socioeconomic conditions have aggravated water scarcity over the past decades. A wide range of studies show that water scarcity will intensify in the future, as a result of both increased consumptive water use and, in some regions, climate change. Although it is well-known that El Niño- Southern Oscillation (ENSO) affects patterns of precipitation and drought at global and regional scales, little attention has yet been paid to the impacts of climate variability on water scarcity conditions, despite its importance for adaptation planning. Therefore, we present the first global-scale sensitivity assessment of water scarcity to ENSO, the most dominant signal of climate variability. We show that over the time period 1961-2010, both water availability and water scarcity conditions are significantly correlated with ENSO-driven climate variability over a large proportion of the global land area (> 28.1 %); an area inhabited by more than 31.4% of the global population. We also found, however, that climate variability alone is often not enough to trigger the actual incidence of water scarcity events. The sensitivity of a region to water scarcity events, expressed in terms of land area or population exposed, is determined by both hydro-climatic and socioeconomic conditions. Currently, the population actually impacted by water scarcity events consists of 39.6% (CTA: consumption-to-availability ratio) and 41.1% (WCI: water crowding index) of the global population, whilst only 11.4% (CTA) and 15.9% (WCI) of the global population is at the same time living in areas sensitive to ENSO-driven climate variability. These results are contrasted, however, by differences in growth rates found under changing socioeconomic conditions, which are relatively high in regions exposed to water scarcity events. Given the correlations found between ENSO and water availability and scarcity

  4. Large-scale hydrological modeling for calculating water stress indices: implications of improved spatiotemporal resolution, surface-groundwater differentiation, and uncertainty characterization.

    Science.gov (United States)

    Scherer, Laura; Venkatesh, Aranya; Karuppiah, Ramkumar; Pfister, Stephan

    2015-04-21

    Physical water scarcities can be described by water stress indices. These are often determined at an annual scale and a watershed level; however, such scales mask seasonal fluctuations and spatial heterogeneity within a watershed. In order to account for this level of detail, first and foremost, water availability estimates must be improved and refined. State-of-the-art global hydrological models such as WaterGAP and UNH/GRDC have previously been unable to reliably reflect water availability at the subbasin scale. In this study, the Soil and Water Assessment Tool (SWAT) was tested as an alternative to global models, using the case study of the Mississippi watershed. While SWAT clearly outperformed the global models at the scale of a large watershed, it was judged to be unsuitable for global scale simulations due to the high calibration efforts required. The results obtained in this study show that global assessments miss out on key aspects related to upstream/downstream relations and monthly fluctuations, which are important both for the characterization of water scarcity in the Mississippi watershed and for water footprints. Especially in arid regions, where scarcity is high, these models provide unsatisfying results.

  5. Water avoidance stress induces frequency through cyclooxygenase-2 expression: a bladder rat model.

    Science.gov (United States)

    Yamamoto, Keisuke; Takao, Tetsuya; Nakayama, Jiro; Kiuchi, Hiroshi; Okuda, Hidenobu; Fukuhara, Shinichiro; Yoshioka, Iwao; Matsuoka, Yasuhiro; Miyagawa, Yasushi; Tsujimura, Akira; Nonomura, Norio

    2012-02-01

    Water avoidance stress is a potent psychological stressor and it is associated with visceral hyperalgesia, which shows degeneration of the urothelial layer mimicking interstitial cystitis. Cyclooxygenase-2 inhibitors have been recognized to ameliorate frequency both in clinical and experimental settings. We investigated the voiding pattern and cyclooxygenase-2 expression in a rat bladder model of water avoidance stress. After being subjected to water avoidance stress or a sham procedure, rats underwent metabolic cage analysis and cystometrography. Real time reverse transcription polymerase chain reaction was carried out to examine cyclooxygenase-2 messenger ribonucleic acid in bladders of rats. Protein expression of cyclooxygenase-2 was analyzed with immunohistochemistry and western blotting. Furthermore, the effects of the cyclooxygenase-2 inhibitor, etodolac, were investigated by carrying out cystometrography, immunohistochemistry and western blotting. Metabolic cage analysis and cystometrography showed significantly shorter intervals and less volume of voiding in water avoidance stress rats. Significantly higher expression of cyclooxygenase-2 messenger ribonucleic acid was verified by reverse transcription polymerase chain reaction. Immunohistochemistry and western blotting showed significantly higher cyclooxygenase-2 protein levels in water avoidance stress bladders. Furthermore, immunohistochemistry showed high cyclooxygenase-2 expression exclusively in smooth muscle cells. All water avoidance stress-induced changes were reduced by cyclooxygenase-2 inhibitor pretreatment. Chronic stress might cause frequency through cyclooxygenase-2 gene upregulation in bladder smooth muscle cells. Further study of cyclooxygenase-2 in the water avoidance stress bladder might provide novel therapeutic modalities for interstitial cystitis. © 2011 The Japanese Urological Association.

  6. Crop yield response to water stress imposed at different growth stages

    International Nuclear Information System (INIS)

    Iqbal, M.; Mahmood Shah, M.; Wisal, M.

    1995-01-01

    Potato requires sufficient soil moisture and fertilization to produce high yields but the present water resoures are limited compared to the cultivable land, field experiments were conduced from 1991 to 1995 to study relationship between yield and crop water use as a function of water stress imposed at different growth stages. The irrigation treatments involved application of full and stress watering s selectively at four growth stages : Establishment , Flowering Tuber formation and ripening. In full watering, full water requirements of the crop were met, i.e., ET sub a = ET sub m whereas in stress watering about half the amount of full watering was applied, i.e., ET sub a < ET sub m. Changes in moisture content of the soil pre files after irrigation were monitored with the help of neutron moisture probe in order to compute ET sub a by the water balance method. The results obtained showed that the tuber yield was produced by full watering ( T 1) and the lowest by continuous stress watering (T 2). A plot of relative yield against relative evapotranspiration deficit revealed that ripening was the lest sensitive whereas early development followed by flowering the most sensitive growth stage to water stress. The crop water use efficiencies were generally higher in the treatments where a combination of normal and stress watering was applied compared to where all - normal watering s were applied. The traditional irrigation practice resulted in wasteful water application with relatively lower yields, hence the results from this project will have high value for the farming community to get this higher yields with scarce water resources. The studies with labelled fertilizer showed that planting and earthing - up were equally important growth stages of potato for applying fertilizer for its efficient utilization. 3 figs; 25 tabs; 12 refs (Author)

  7. Is the available cropland and water enough for food demand? A global perspective of the Land-Water-Food nexus

    Science.gov (United States)

    Ibarrola-Rivas, M. J.; Granados-Ramírez, R.; Nonhebel, S.

    2017-12-01

    Land and water are essential local resources for food production but are limited. The main drivers of increasing food demand are population growth and dietary changes, which depend on the socioeconomic situation of the population. These two factors affect the availability of local resources: population growth reduces the land and water per person; and adoption of affluent diets increases the demand for land and water per person. This study shows potentials of global food supply by linking food demand drivers with national land and water availability. Whether the available land and water is enough to meet national food demand was calculated for 187 countries. The calculations were performed for the past situation (1960 and 2010) and to assess four future scenarios (2050) to discuss different paths of diets, population numbers and agricultural expansion. Inclusion of the demand perspective in the analysis has shown stronger challenges for future global food supply than have other studies. The results show that with the "business as usual" scenario, 40% of the global population in 2050 will live in countries with not enough land nor water to meet the demands of their population. Restriction to basic diets will be the most effective in lowering both land and water constraints. Our results identify both food production and food demand factors, and the regions that may experience the strongest challenges in 2050.

  8. Global impacts of conversions from natural to agricultural ecosystems on water resources: Quantity versus quality

    Science.gov (United States)

    Scanlon, Bridget R.; Jolly, Ian; Sophocleous, Marios; Zhang, Lu

    2007-03-01

    Past land use changes have greatly impacted global water resources, with often opposing effects on water quantity and quality. Increases in rain-fed cropland (460%) and pastureland (560%) during the past 300 years from forest and grasslands decreased evapotranspiration and increased recharge (two orders of magnitude) and streamflow (one order of magnitude). However, increased water quantity degraded water quality by mobilization of salts, salinization caused by shallow water tables, and fertilizer leaching into underlying aquifers that discharge to streams. Since the 1950s, irrigated agriculture has expanded globally by 174%, accounting for ˜90% of global freshwater consumption. Irrigation based on surface water reduced streamflow and raised water tables resulting in waterlogging in many areas (China, India, and United States). Marked increases in groundwater-fed irrigation in the last few decades in these areas has lowered water tables (≤1 m/yr) and reduced streamflow. Degradation of water quality in irrigated areas has resulted from processes similar to those in rain-fed agriculture: salt mobilization, salinization in waterlogged areas, and fertilizer leaching. Strategies for remediating water resource problems related to agriculture often have opposing effects on water quantity and quality. Long time lags (decades to centuries) between land use changes and system response (e.g., recharge, streamflow, and water quality), particularly in semiarid regions, mean that the full impact of land use changes has not been realized in many areas and remediation to reverse impacts will also take a long time. Future land use changes should consider potential impacts on water resources, particularly trade-offs between water, salt, and nutrient balances, to develop sustainable water resources to meet human and ecosystem needs.

  9. AFLP marker linked to water-stress-tolerant bulks in barley (Hordeum vulgare L.

    Directory of Open Access Journals (Sweden)

    A. Altinkut

    2003-01-01

    Full Text Available The amplified fragment length polymorphism (AFLP assay is an efficient method for the identification of molecular markers, useful in the improvement of numerous crop species. Bulked Segregant Analysis (BSA was used to identify AFLP markers associated with water-stress tolerance in barley, as this would permit rapid selection of water-stress tolerant genotypes in breeding programs. AFLP markers linked to water-stress tolerance was identified in two DNA pools (tolerant and sensitive, which were established using selected F2 individuals resulting from a cross between water-stress-tolerant and sensitive barley parental genotypes, based on their paraquat (PQ tolerance, leaf size, and relative water content (RWC. All these three traits were previously shown to be associated with water-stress tolerance in segregating F2 progeny of the barley cross used in a previous study. AFLP analysis was then performed on these DNA pools, using 40 primer pairs to detect AFLP fragments that are present/absent, respectively, in the two pools and their parental lines. One separate AFLP fragment, which was present in the tolerant parent and in the tolerant bulk, but absent in the sensitive parent and in the sensitive bulk, was identified. Polymorphism of the AFLP marker was tested among tolerant and sensitive F2 individuals. The presence of this marker that is associated with water-stress tolerance will greatly enhance selection for paraquat and water-stress tolerant genotypes in future breeding programs.

  10. A global hydrological simulation to specify the sources of water used by humans

    Science.gov (United States)

    Hanasaki, Naota; Yoshikawa, Sayaka; Pokhrel, Yadu; Kanae, Shinjiro

    2018-01-01

    Humans abstract water from various sources to sustain their livelihood and society. Some global hydrological models (GHMs) include explicit schemes of human water abstraction, but the representation and performance of these schemes remain limited. We substantially enhanced the water abstraction schemes of the H08 GHM. This enabled us to estimate water abstraction from six major water sources, namely, river flow regulated by global reservoirs (i.e., reservoirs regulating the flow of the world's major rivers), aqueduct water transfer, local reservoirs, seawater desalination, renewable groundwater, and nonrenewable groundwater. In its standard setup, the model covers the whole globe at a spatial resolution of 0.5° × 0.5°, and the calculation interval is 1 day. All the interactions were simulated in a single computer program, and all water fluxes and storage were strictly traceable at any place and time during the simulation period. A global hydrological simulation was conducted to validate the performance of the model for the period of 1979-2013 (land use was fixed for the year 2000). The simulated water fluxes for water abstraction were validated against those reported in earlier publications and showed a reasonable agreement at the global and country level. The simulated monthly river discharge and terrestrial water storage (TWS) for six of the world's most significantly human-affected river basins were compared with gauge observations and the data derived from the Gravity Recovery and Climate Experiment (GRACE) satellite mission. It is found that the simulation including the newly added schemes outperformed the simulation without human activities. The simulated results indicated that, in 2000, of the 3628±75 km3 yr-1 global freshwater requirement, 2839±50 km3 yr-1 was taken from surface water and 789±30 km3 yr-1 from groundwater. Streamflow, aqueduct water transfer, local reservoirs, and seawater desalination accounted for 1786±23, 199±10, 106±5, and 1.8

  11. Silicon improves seed germination and alleviates oxidative stress of bud seedlings in tomato under water deficit stress.

    Science.gov (United States)

    Shi, Yu; Zhang, Yi; Yao, Hejin; Wu, Jiawen; Sun, Hao; Gong, Haijun

    2014-05-01

    The beneficial effects of silicon on plant growth and development under drought have been widely reported. However, little information is available on the effects of silicon on seed germination under drought. In this work, the effects of exogenous silicon (0.5 mM) on the seed germination and tolerance performance of tomato (Solanum lycopersicum L.) bud seedlings under water deficit stress simulated by 10% (w/v) polyethylene glycol (PEG-6000) were investigated in four cultivars ('Jinpengchaoguan', 'Zhongza No.9', 'Houpi L402' and 'Oubao318'). The results showed that the seed germination percentage was notably decreased in the four cultivars under water stress, and it was significantly improved by added silicon. Compared with the non-silicon treatment, silicon addition increased the activities of superoxide dismutase (SOD) and catalase (CAT), and decreased the production of superoxide anion (O2·) and hydrogen peroxide (H2O2) in the radicles of bud seedlings under water stress. Addition of silicon decreased the total phenol concentrations in radicles under water stress, which might contribute to the decrease of peroxidase (POD) activity, as observed in the in vivo and in vitro experiments. The decrease of POD activity might contribute to a less accumulation of hydroxyl radical (·OH) under water stress. Silicon addition also decreased the concentrations of malondialdehyde (MDA) in the radicles under stress, indicating decreased lipid peroxidation. These results suggest that exogenous silicon could improve seed germination and alleviate oxidative stress to bud seedling of tomato by enhancing antioxidant defense. The positive effects of silicon observed in a silicon-excluder also suggest the active involvement of silicon in biochemical processes in plants. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  12. The world’s road to water scarcity: shortage and stress in the 20th century and pathways towards sustainability

    Science.gov (United States)

    Kummu, M.; Guillaume, J. H. A.; de Moel, H.; Eisner, S.; Flörke, M.; Porkka, M.; Siebert, S.; Veldkamp, T. I. E.; Ward, P. J.

    2016-01-01

    Water scarcity is a rapidly growing concern around the globe, but little is known about how it has developed over time. This study provides a first assessment of continuous sub-national trajectories of blue water consumption, renewable freshwater availability, and water scarcity for the entire 20th century. Water scarcity is analysed using the fundamental concepts of shortage (impacts due to low availability per capita) and stress (impacts due to high consumption relative to availability) which indicate difficulties in satisfying the needs of a population and overuse of resources respectively. While water consumption increased fourfold within the study period, the population under water scarcity increased from 0.24 billion (14% of global population) in the 1900s to 3.8 billion (58%) in the 2000s. Nearly all sub-national trajectories show an increasing trend in water scarcity. The concept of scarcity trajectory archetypes and shapes is introduced to characterize the historical development of water scarcity and suggest measures for alleviating water scarcity and increasing sustainability. Linking the scarcity trajectories to other datasets may help further deepen understanding of how trajectories relate to historical and future drivers, and hence help tackle these evolving challenges. PMID:27934888

  13. The world's road to water scarcity: shortage and stress in the 20th century and pathways towards sustainability.

    Science.gov (United States)

    Kummu, M; Guillaume, J H A; de Moel, H; Eisner, S; Flörke, M; Porkka, M; Siebert, S; Veldkamp, T I E; Ward, P J

    2016-12-09

    Water scarcity is a rapidly growing concern around the globe, but little is known about how it has developed over time. This study provides a first assessment of continuous sub-national trajectories of blue water consumption, renewable freshwater availability, and water scarcity for the entire 20 th century. Water scarcity is analysed using the fundamental concepts of shortage (impacts due to low availability per capita) and stress (impacts due to high consumption relative to availability) which indicate difficulties in satisfying the needs of a population and overuse of resources respectively. While water consumption increased fourfold within the study period, the population under water scarcity increased from 0.24 billion (14% of global population) in the 1900s to 3.8 billion (58%) in the 2000s. Nearly all sub-national trajectories show an increasing trend in water scarcity. The concept of scarcity trajectory archetypes and shapes is introduced to characterize the historical development of water scarcity and suggest measures for alleviating water scarcity and increasing sustainability. Linking the scarcity trajectories to other datasets may help further deepen understanding of how trajectories relate to historical and future drivers, and hence help tackle these evolving challenges.

  14. Building a Course on Global Sustainability using the grand challenges of Energy-Water-Climate

    Science.gov (United States)

    Myers, J. D.

    2012-12-01

    GEOL1600: Global Sustainability: Managing the Earth's Resources is a lower division integrated science course at the University of Wyoming that fulfills the university's science requirement. Course content and context has been developed using the grand challenge nexus of energy-water-and climate (EWC). The interconnection of these issues, their social relevance and timeliness has provided a framework that gives students an opportunity to recognize why STEM is relevant to their lives regardless of their ultimate professional career choices. The EWC nexus provides the filter to sieve the course's STEM content. It also provides an ideal mechanism by which the non-STEM perspectives important in grand challenge solutions can be seamlessly incorporated in the course. Through a combination of content and context, the relevance of these issues engage students in their own learning. Development of the course followed the Grand Challenge Scientific Literacy (GCSL) model independently developed by the author and two colleagues at the University of Wyoming. This course model stresses science principles centered on the nature of science (e.g., fundamental premises, habits of mind, critical thinking) and unifying scientific concepts (e.g., methods and tools, experimentation, modeling). Grand challenge principles identify the STEM and non-STEM concepts needed to understand the grand challenges, drawing on multiple STEM and non-STEM disciplines and subjects (i.e., economics, politics, unintended consequences, roles of stakeholders). Using the EWC nexus filter and building on the Grand Challenge Principles, specific content included in the course is selected is that most relevant to understanding the Grand Challenges, thereby stressing content depth over breadth. Because quantitative data and reasoning is critical to effectively evaluating challenge solutions, QR is a component of nearly all class activities, while engineering and technology aspects of grand challenges are

  15. Globalization

    Directory of Open Access Journals (Sweden)

    Tulio Rosembuj

    2006-12-01

    Full Text Available There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

  16. Globalization

    OpenAIRE

    Tulio Rosembuj

    2006-01-01

    There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

  17. Residual stress improved by water jet peening using cavitation for small-diameter pipe inner surfaces

    International Nuclear Information System (INIS)

    Yasuo, Nakamura; Toshizo, Ohya; Koji, Okimura

    2001-01-01

    As one of degradation conditions on components used in water, the overlapping effect of environment, material and stress might cause stress corrosion cracking (SCC). Especially, for the tensile residual stress produced by welding, it is particularly effective to reduce the tensile residual stress on the material surface to prevent SCC. In this paper, the residual stress improvement method using cavitation impact generated by a water jet, called Water Jet Peening (WJP), has been developed as the maintenance technology for the inner surfaces of small-diameter Ni-Cr-Fe alloy (Alloy 600) pipes. As the results, by WJP for the inner surface of Alloy 600 pipe (inner diameter; approximately 10-15 mm), we confirmed that the compressive stress generated within the range from the surface to the inner part about 0.5 mm deep and took a maximum value about 350 MPa on the surface. (author)

  18. A short generic measure of work stress in the era of globalization: effort-reward imbalance.

    Science.gov (United States)

    Siegrist, Johannes; Wege, Natalia; Pühlhofer, Frank; Wahrendorf, Morten

    2009-08-01

    We evaluate psychometric properties of a short version of the original effort-reward imbalance (ERI) questionnaire. This measure is of interest in the context of assessing stressful work conditions in the era of economic globalization. In a representative sample of 10,698 employed men and women participating in the longitudinal Socio-Economic Panel (SOEP) in Germany, a short version of the ERI questionnaire was included in the 2006 panel wave. Structural equation modeling and logistic regression analysis were applied. In addition to satisfactory internal consistency of scales, a model representing the theoretical structure of the scales provided the best data fit in a competitive test (RMSEA = 0.059, CAIC = 4124.19). Scoring high on the ERI scales was associated with elevated risks of poor self-rated health. This short version of the ERI questionnaire reveals satisfactory psychometric properties, and can be recommended for further use in research and practice.

  19. How to Assess Vulnerabilities of Water Policies to Global Change?

    Science.gov (United States)

    Kumar, A.; Haasnoot, M.; Weijs, S.

    2017-12-01

    Water managers are confronted with uncertainties arising from hydrological, societal, economical and political drivers. To manage these uncertainties two paradigms have been identified: top-down and bottom-up approaches. Top-down or prediction-based approaches use socio-economic scenarios together with a discrete set of GCM projections (often downscaled) to assess the expected impact of drivers and policies on water resource system through various hydrological and social systems models. Adaptation strategies to alleviate these impacts are then identified and tested against the scenarios. To address GCM and downscaling uncertainties, these approaches put more focus on climate predictions, rather than the decision problem itself. Triggered by the wish to have a more scenario-neutral approach and address downscaling uncertainties, recent analyses have been shifted towards vulnerability-based (bottom-up or decision-centric) approaches. They begin at the local scale by addressing socio-economic responses to climate, often involving stakeholder's input; identify vulnerabilities under a larger sample of plausible futures and evaluate sensitivity and robustness of possible adaptation options. Several bottom-up approaches have emerged so far and are increasingly recommended. Fundamentally they share several core ideas, however, subtle differences exist in vulnerability assessment, visualization tools for exploring vulnerabilities and computational methods used for identifying robust water policies. Through this study, we try to identify how these approaches are progressing, how the climate and non-climate uncertainties are being confronted and how to integrate existing and new tools. We find that choice of a method may depend on the number of vulnerability drivers identified and type of threshold levels (environmental conditions or policy objectives) defined. Certain approaches are suited well for assessing adaptive capacities, tipping points and sequencing of decisions

  20. Evolution of Water Supply, Sanitation, Wastewater, and Stormwater Technologies Globally

    Directory of Open Access Journals (Sweden)

    Andreas N. Angelakis

    2015-02-01

    Full Text Available This paper provides an outline of history of hydro-technologies in the west and the east. It is an overview of the special issue on “the evolution of hydro-technologies globally”, in which the key topics regarding the history of water and sanitation worldwide, and its importance to future cities are presented and discussed. It covers a wide range of relevant historical issues, and is presented in three categories: productivity assessment, institutional framework and mechanisms, and governance aspects. This paper concludes by discussing the challenges on future research in this field of study.

  1. Strategies for ensuring global consistency/comparability of water-quality data

    Science.gov (United States)

    Klein, J.M.

    1999-01-01

    In the past 20 years the water quality of the United States has improved remarkably-the waters are safer for drinking, swimming, and fishing. However, despite many accomplishments, it is still difficult to answer such basic questions as: 'How clean is the water?' and 'How is it changing over time?' These same questions exist on a global scale as well. In order to focus water-data issues in the United States, a national Intergovernmental Task Force on Monitoring Water Quality (ITFM) was initiated for public and private organizations, whereby key elements involved in data collection, analysis, storage, and management could be made consistent and comparable. The ITFM recommended and its members are implementing a nationwide strategy to improve water-quality monitoring, assessment, and reporting activities. The intent of this paper is to suggest that a voluntary effort be initiated to ensure the comparability and utility of hydrological data on a global basis. Consistent, long-term data sets that are comparable are necessary in order to formulate ideas regarding regional and global trends in water quantity and quality. The author recommends that a voluntary effort similar to the ITFM effort be utilized. The strategy proposed would involve voluntary representation from countries and international organizations (e.g. World Health Organization) involved in drinking-water assessments and/or ambient water-quality monitoring. Voluntary partnerships such as this will improve curability to reduce health risks and achieve a better return on public and private investments in monitoring, environmental protection, and natural resource management, and result in a collaborative process that will save millions of dollars.In this work it is suggested that a voluntary effort be initiated to ensure the comparability and utility of hydrological data on a global basis. The strategy proposed would involve voluntary representation from countries and international organizations involved in

  2. Globalization of water and food through international trade: impacts on food security, resilience and justice

    Science.gov (United States)

    D'Odorico, P.; Carr, J. A.; Seekell, D. A.; Suweis, S. S.

    2015-12-01

    The global distribution of water resources in general depends on geographic conditions but can be (virtually) modified by humans through mechanisms of globalization, such as trade, that make food commodities available to populations living far from the production regions. While trade is expected to improve access to food and (virtual) water, its impact on the global food system and its vulnerability to shocks remains poorly understood. It is also unclear who benefits from trade and whether it contributes to inequality and justice in resource redistribution. We reconstruct the global patterns of food trade and show with a simple model how the ongoing intensification of imports and exports has eroded the resilience of the global food system. Drawing on human rights theory, we investigate the relationship between inequality and injustice in access to water and food. We assess the fulfillment of positive and negative water and food rights and evaluate the obligations arising from the need to ensure that these rights are met throughout the world. We find that trade enhances the vulnerability to shocks but overall increase the number of people whose water and food rights are met.

  3. Hyperspectral detection of a subsurface CO2 leak in the presence of water stressed vegetation.

    Directory of Open Access Journals (Sweden)

    Gabriel J Bellante

    Full Text Available Remote sensing of vegetation stress has been posed as a possible large area monitoring tool for surface CO2 leakage from geologic carbon sequestration (GCS sites since vegetation is adversely affected by elevated CO2 levels in soil. However, the extent to which remote sensing could be used for CO2 leak detection depends on the spectral separability of the plant stress signal caused by various factors, including elevated soil CO2 and water stress. This distinction is crucial to determining the seasonality and appropriateness of remote GCS site monitoring. A greenhouse experiment tested the degree to which plants stressed by elevated soil CO2 could be distinguished from plants that were water stressed. A randomized block design assigned Alfalfa plants (Medicago sativa to one of four possible treatment groups: 1 a CO2 injection group; 2 a water stress group; 3 an interaction group that was subjected to both water stress and CO2 injection; or 4 a group that received adequate water and no CO2 injection. Single date classification trees were developed to identify individual spectral bands that were significant in distinguishing between CO2 and water stress agents, in addition to a random forest classifier that was used to further understand and validate predictive accuracies. Overall peak classification accuracy was 90% (Kappa of 0.87 for the classification tree analysis and 83% (Kappa of 0.77 for the random forest classifier, demonstrating that vegetation stressed from an underground CO2 leak could be accurately discerned from healthy vegetation and areas of co-occurring water stressed vegetation at certain times. Plants appear to hit a stress threshold, however, that would render detection of a CO2 leak unlikely during severe drought conditions. Our findings suggest that early detection of a CO2 leak with an aerial or ground-based hyperspectral imaging system is possible and could be an important GCS monitoring tool.

  4. Hyperspectral detection of a subsurface CO2 leak in the presence of water stressed vegetation.

    Science.gov (United States)

    Bellante, Gabriel J; Powell, Scott L; Lawrence, Rick L; Repasky, Kevin S; Dougher, Tracy

    2014-01-01

    Remote sensing of vegetation stress has been posed as a possible large area monitoring tool for surface CO2 leakage from geologic carbon sequestration (GCS) sites since vegetation is adversely affected by elevated CO2 levels in soil. However, the extent to which remote sensing could be used for CO2 leak detection depends on the spectral separability of the plant stress signal caused by various factors, including elevated soil CO2 and water stress. This distinction is crucial to determining the seasonality and appropriateness of remote GCS site monitoring. A greenhouse experiment tested the degree to which plants stressed by elevated soil CO2 could be distinguished from plants that were water stressed. A randomized block design assigned Alfalfa plants (Medicago sativa) to one of four possible treatment groups: 1) a CO2 injection group; 2) a water stress group; 3) an interaction group that was subjected to both water stress and CO2 injection; or 4) a group that received adequate water and no CO2 injection. Single date classification trees were developed to identify individual spectral bands that were significant in distinguishing between CO2 and water stress agents, in addition to a random forest classifier that was used to further understand and validate predictive accuracies. Overall peak classification accuracy was 90% (Kappa of 0.87) for the classification tree analysis and 83% (Kappa of 0.77) for the random forest classifier, demonstrating that vegetation stressed from an underground CO2 leak could be accurately discerned from healthy vegetation and areas of co-occurring water stressed vegetation at certain times. Plants appear to hit a stress threshold, however, that would render detection of a CO2 leak unlikely during severe drought conditions. Our findings suggest that early detection of a CO2 leak with an aerial or ground-based hyperspectral imaging system is possible and could be an important GCS monitoring tool.

  5. The action of chemical and mechanical stresses on single and dual species biofilm removal of drinking water bacteria.

    Science.gov (United States)

    Gomes, I B; Lemos, M; Mathieu, L; Simões, M; Simões, L C

    2018-08-01

    The presence of biofilms in drinking water distribution systems (DWDS) is a global public health concern as they can harbor pathogenic microorganisms. Sodium hypochlorite (NaOCl) is the most commonly used disinfectant for microbial growth control in DWDS. However, its effect on biofilm removal is still unclear. This work aims to evaluate the effects of the combination of chemical (NaOCl) and mechanical stresses on the removal of single and dual species biofilms of two bacteria isolated from DWDS and considered opportunistic, Acinectobacter calcoaceticus and Stenotrophomonas maltophilia. A rotating cylinder reactor was successfully used for the first time in drinking water biofilm studies with polyvinyl chloride as substratum. The single and dual species biofilms presented different characteristics in terms of metabolic activity, mass, density, thickness and content of proteins and polysaccharides. Their complete removal was not achieved even when a high NaOCl concentrations and an increasing series of shear stresses (from 2 to 23Pa) were applied. In general, NaOCl pre-treatment did not improve the impact of mechanical stress on biofilm removal. Dual species biofilms were colonized mostly by S. maltophilia and were more susceptible to chemical and mechanical stresses than these single species. The most efficient treatment (93% biofilm removal) was the combination of NaOCl at 175mg·l -1 with mechanical stress against dual species biofilms. Of concern was the high tolerance of S. maltophilia to chemical and mechanical stresses in both single and dual species biofilms. The overall results demonstrate the inefficacy of NaOCl on biofilm removal even when combined with high shear stresses. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Water and Forest Health: Drought Stress as a Core Driver of Forest Disturbances and Tree Mortality in Western North America

    Science.gov (United States)

    Allen, C. D.; Williams, P.

    2012-12-01

    Increasing warmth and dry climate conditions have affected large portions of western North America in recent years, causing elevated levels of both chronic and acute forest drought stress. In turn, increases in drought stress amplify the incidence and severity of the most significant forest disturbances in this region, including wildfire, drought-induced tree mortality, and outbreaks of damaging insects and diseases. Regional patterns of drought stress and various forest disturbances are reviewed, including interactions among climate and the various disturbance processes; similar global-scale patterns and trends of drought-amplified forest die-off and high-severity wildfire also are addressed. New research is presented that derives a tree-ring-based Forest Drought Stress Index (FDSI) for the three most widespread conifer species (Pinus edulis, Pinus ponderosa, and Pseudotsuga menziesii) in the southwestern US (Arizona, New Mexico), demonstrating nonlinear escalation of FDSI to levels unprecedented in the past 1000 years, in response to both drought and especially recent warming. This new work further highlights strong correlations between drought stress and amplified forest disturbances (fire, bark beetle outbreaks), and projects that by ca. 2050 anticipated regional warming will cause mean FDSI levels to reach extreme levels that may exceed thresholds for the survival of current tree species in large portions of their current range. Given recent trends of forest disturbance and projections for substantially warmer temperatures and greater drought stress for much of western North America in coming years, the growing risks to western forest health are becoming clear. This emerging understanding suggests an urgent need to determine potentials and methods for managing water on-site to maintain the vigor and resilience of western forests in the face of increasing levels of climate-induced water stress.

  7. Infrared thermometry and the crop water stress index. II. Sampling procedures and interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, B. R. [BP Research, Cleveland, OH (United States); Nielsen, D. C.; Shock, C. C.

    1992-10-15

    Infrared thermometry can be a valuable research and production tool for detecting and quantifying water stress in plants, as shown by a large volume of published research. Users of infrared thermometers (IRT) should be aware of the many equipment, environmental, and plant factors influencing canopy temperature measured by an IRT. The purpose of this paper is to describe factors influencing measured plant temperature, outline sampling procedures that will produce reliable Crop Water Stress Index (CWSI) values, and offer interpretations of CWSI and plant temperatures relative to crop production and other water stress parameters by reviewing previously conducted research. Factors that are considered are IRT condition, configuration, and position; psychrometer location; wind speed; solar radiation; time of day; leaf area and orientation; and appropriate non-water-stressed baseline equation. Standard sampling and CWSI calculation procedures are proposed. Use of CWSI with crops varying in type of response to water stress is described. Previously conducted research on plant temperatures or CWSI is tabulated by crop and water stress parameters measured. The paper provides valuable information to assist interested users of IRTs in making reliable water stress measurements. (author)

  8. Infrared thermometry and the crop water stress index. II. Sampling procedures and interpretation

    International Nuclear Information System (INIS)

    Gardner, B.R.; Nielsen, D.C.; Shock, C.C.

    1992-01-01

    Infrared thermometry can be a valuable research and production tool for detecting and quantifying water stress in plants, as shown by a large volume of published research. Users of infrared thermometers (IRT) should be aware of the many equipment, environmental, and plant factors influencing canopy temperature measured by an IRT. The purpose of this paper is to describe factors influencing measured plant temperature, outline sampling procedures that will produce reliable Crop Water Stress Index (CWSI) values, and offer interpretations of CWSI and plant temperatures relative to crop production and other water stress parameters by reviewing previously conducted research. Factors that are considered are IRT condition, configuration, and position; psychrometer location; wind speed; solar radiation; time of day; leaf area and orientation; and appropriate non-water-stressed baseline equation. Standard sampling and CWSI calculation procedures are proposed. Use of CWSI with crops varying in type of response to water stress is described. Previously conducted research on plant temperatures or CWSI is tabulated by crop and water stress parameters measured. The paper provides valuable information to assist interested users of IRTs in making reliable water stress measurements. (author)

  9. Hyperresolution global land surface modeling: Meeting a grand challenge for monitoring Earth's terrestrial water

    Science.gov (United States)

    Wood, Eric F.; Roundy, Joshua K.; Troy, Tara J.; van Beek, L. P. H.; Bierkens, Marc F. P.; Blyth, Eleanor; de Roo, Ad; DöLl, Petra; Ek, Mike; Famiglietti, James; Gochis, David; van de Giesen, Nick; Houser, Paul; Jaffé, Peter R.; Kollet, Stefan; Lehner, Bernhard; Lettenmaier, Dennis P.; Peters-Lidard, Christa; Sivapalan, Murugesu; Sheffield, Justin; Wade, Andrew; Whitehead, Paul

    2011-05-01

    Monitoring Earth's terrestrial water conditions is critically important to many hydrological applications such as global food production; assessing water resources sustainability; and flood, drought, and climate change prediction. These needs have motivated the development of pilot monitoring and prediction systems for terrestrial hydrologic and vegetative states, but to date only at the rather coarse spatial resolutions (˜10-100 km) over continental to global domains. Adequately addressing critical water cycle science questions and applications requires systems that are implemented globally at much higher resolutions, on the order of 1 km, resolutions referred to as hyperresolution in the context of global land surface models. This opinion paper sets forth the needs and benefits for a system that would monitor and predict the Earth's terrestrial water, energy, and biogeochemical cycles. We discuss six major challenges in developing a system: improved representation of surface-subsurface interactions due to fine-scale topography and vegetation; improved representation of land-atmospheric interactions and resulting spatial information on soil moisture and evapotranspiration; inclusion of water quality as part of the biogeochemical cycle; representation of human impacts from water management; utilizing massively parallel computer systems and recent computational advances in solving hyperresolution models that will have up to 109 unknowns; and developing the required in situ and remote sensing global data sets. We deem the development of a global hyperresolution model for monitoring the terrestrial water, energy, and biogeochemical cycles a "grand challenge" to the community, and we call upon the international hydrologic community and the hydrological science support infrastructure to endorse the effort.

  10. Hyperresolution Global Land Surface Modeling: Meeting a Grand Challenge for Monitoring Earth's Terrestrial Water

    Science.gov (United States)

    Wood, Eric F.; Roundy, Joshua K.; Troy, Tara J.; van Beek, L. P. H.; Bierkens, Marc F. P.; 4 Blyth, Eleanor; de Roo, Ad; Doell. Petra; Ek, Mike; Famiglietti, James; hide

    2011-01-01

    Monitoring Earth's terrestrial water conditions is critically important to many hydrological applications such as global food production; assessing water resources sustainability; and flood, drought, and climate change prediction. These needs have motivated the development of pilot monitoring and prediction systems for terrestrial hydrologic and vegetative states, but to date only at the rather coarse spatial resolutions (approx.10-100 km) over continental to global domains. Adequately addressing critical water cycle science questions and applications requires systems that are implemented globally at much higher resolutions, on the order of 1 km, resolutions referred to as hyperresolution in the context of global land surface models. This opinion paper sets forth the needs and benefits for a system that would monitor and predict the Earth's terrestrial water, energy, and biogeochemical cycles. We discuss six major challenges in developing a system: improved representation of surface-subsurface interactions due to fine-scale topography and vegetation; improved representation of land-atmospheric interactions and resulting spatial information on soil moisture and evapotranspiration; inclusion of water quality as part of the biogeochemical cycle; representation of human impacts from water management; utilizing massively parallel computer systems and recent computational advances in solving hyperresolution models that will have up to 10(exp 9) unknowns; and developing the required in situ and remote sensing global data sets. We deem the development of a global hyperresolution model for monitoring the terrestrial water, energy, and biogeochemical cycles a grand challenge to the community, and we call upon the international hydrologic community and the hydrological science support infrastructure to endorse the effort.

  11. Sub-seasonal predictability of water scarcity at global and local scale

    Science.gov (United States)

    Wanders, N.; Wada, Y.; Wood, E. F.

    2016-12-01

    Forecasting the water demand and availability for agriculture and energy production has been neglected in previous research, partly due to the fact that most large-scale hydrological models lack the skill to forecast human water demands at sub-seasonal time scale. We study the potential of a sub-seasonal water scarcity forecasting system for improved water management decision making and improved estimates of water demand and availability. We have generated 32 years of global sub-seasonal multi-model water availability, demand and scarcity forecasts. The quality of the forecasts is compared to a reference forecast derived from resampling historic weather observations. The newly developed system has been evaluated for both the global scale and in a real-time local application in the Sacramento valley for the Trinity, Shasta and Oroville reservoirs, where the water demand for agriculture and hydropower is high. On the global scale we find that the reference forecast shows high initial forecast skill (up to 8 months) for water scarcity in the eastern US, Central Asia and Sub-Saharan Africa. Adding dynamical sub-seasonal forecasts results in a clear improvement for most regions in the world, increasing the forecasts' lead time by 2 or more months on average. The strongest improvements are found in the US, Brazil, Central Asia and Australia. For the Sacramento valley we can accurately predict anomalies in the reservoir inflow, hydropower potential and the downstream irrigation water demand 6 months in advance. This allow us to forecast potential water scarcity in the Sacramento valley and adjust the reservoir management to prevent deficits in energy or irrigation water availability. The newly developed forecast system shows that it is possible to reduce the vulnerability to upcoming water scarcity events and allows optimization of the distribution of the available water between the agricultural and energy sector half a year in advance.

  12. A global, 30-m resolution land-surface water body dataset for 2000

    Science.gov (United States)

    Feng, M.; Sexton, J. O.; Huang, C.; Song, D. X.; Song, X. P.; Channan, S.; Townshend, J. R.

    2014-12-01

    Inland surface water is essential to terrestrial ecosystems and human civilization. The distribution of surface water in space and its change over time are related to many agricultural, environmental and ecological issues, and are important factors that must be considered in human socioeconomic development. Accurate mapping of surface water is essential for both scientific research and policy-driven applications. Satellite-based remote sensing provides snapshots of Earth's surface and can be used as the main input for water mapping, especially in large areas. Global water areas have been mapped with coarse resolution remotely sensed data (e.g., the Moderate Resolution Imaging Spectroradiometer (MODIS)). However, most inland rivers and water bodies, as well as their changes, are too small to map at such coarse resolutions. Landsat TM (Thematic Mapper) and ETM+ (Enhanced Thematic Mapper Plus) imagery has a 30m spatial resolution and provides decades of records (~40 years). Since 2008, the opening of the Landsat archive, coupled with relatively lower costs associated with computing and data storage, has made comprehensive study of the dynamic changes of surface water over large even global areas more feasible. Although Landsat images have been used for regional and even global water mapping, the method can hardly be automated due to the difficulties on distinguishing inland surface water with variant degrees of impurities and mixing of soil background with only Landsat data. The spectral similarities to other land cover types, e.g., shadow and glacier remnants, also cause misidentification. We have developed a probabilistic based automatic approach for mapping inland surface water bodies. Landsat surface reflectance in multiple bands, derived water indices, and data from other sources are integrated to maximize the ability of identifying water without human interference. The approach has been implemented with open-source libraries to facilitate processing large

  13. Global analysis of transcriptome responses and gene expression profiles to cold stress of Jatropha curcas L.

    Science.gov (United States)

    Wang, Haibo; Zou, Zhurong; Wang, Shasha; Gong, Ming

    2013-01-01

    Jatropha curcas L., also called the Physic nut, is an oil-rich shrub with multiple uses, including biodiesel production, and is currently exploited as a renewable energy resource in many countries. Nevertheless, because of its origin from the tropical MidAmerican zone, J. curcas confers an inherent but undesirable characteristic (low cold resistance) that may seriously restrict its large-scale popularization. This adaptive flaw can be genetically improved by elucidating the mechanisms underlying plant tolerance to cold temperatures. The newly developed Illumina Hiseq™ 2000 RNA-seq and Digital Gene Expression (DGE) are deep high-throughput approaches for gene expression analysis at the transcriptome level, using which we carefully investigated the gene expression profiles in response to cold stress to gain insight into the molecular mechanisms of cold response in J. curcas. In total, 45,251 unigenes were obtained by assembly of clean data generated by RNA-seq analysis of the J. curcas transcriptome. A total of 33,363 and 912 complete or partial coding sequences (CDSs) were determined by protein database alignments and ESTScan prediction, respectively. Among these unigenes, more than 41.52% were involved in approximately 128 known metabolic or signaling pathways, and 4,185 were possibly associated with cold resistance. DGE analysis was used to assess the changes in gene expression when exposed to cold condition (12°C) for 12, 24, and 48 h. The results showed that 3,178 genes were significantly upregulated and 1,244 were downregulated under cold stress. These genes were then functionally annotated based on the transcriptome data from RNA-seq analysis. This study provides a global view of transcriptome response and gene expression profiling of J. curcas in response to cold stress. The results can help improve our current understanding of the mechanisms underlying plant cold resistance and favor the screening of crucial genes for genetically enhancing cold resistance

  14. Global analysis of transcriptome responses and gene expression profiles to cold stress of Jatropha curcas L.

    Directory of Open Access Journals (Sweden)

    Haibo Wang

    Full Text Available BACKGROUND: Jatropha curcas L., also called the Physic nut, is an oil-rich shrub with multiple uses, including biodiesel production, and is currently exploited as a renewable energy resource in many countries. Nevertheless, because of its origin from the tropical MidAmerican zone, J. curcas confers an inherent but undesirable characteristic (low cold resistance that may seriously restrict its large-scale popularization. This adaptive flaw can be genetically improved by elucidating the mechanisms underlying plant tolerance to cold temperatures. The newly developed Illumina Hiseq™ 2000 RNA-seq and Digital Gene Expression (DGE are deep high-throughput approaches for gene expression analysis at the transcriptome level, using which we carefully investigated the gene expression profiles in response to cold stress to gain insight into the molecular mechanisms of cold response in J. curcas. RESULTS: In total, 45,251 unigenes were obtained by assembly of clean data generated by RNA-seq analysis of the J. curcas transcriptome. A total of 33,363 and 912 complete or partial coding sequences (CDSs were determined by protein database alignments and ESTScan prediction, respectively. Among these unigenes, more than 41.52% were involved in approximately 128 known metabolic or signaling pathways, and 4,185 were possibly associated with cold resistance. DGE analysis was used to assess the changes in gene expression when exposed to cold condition (12°C for 12, 24, and 48 h. The results showed that 3,178 genes were significantly upregulated and 1,244 were downregulated under cold stress. These genes were then functionally annotated based on the transcriptome data from RNA-seq analysis. CONCLUSIONS: This study provides a global view of transcriptome response and gene expression profiling of J. curcas in response to cold stress. The results can help improve our current understanding of the mechanisms underlying plant cold resistance and favor the screening of

  15. Global lower mesospheric water vapor revealed by LIMS observations

    Science.gov (United States)

    Gordley, L. L.; Russell, J. M., III; Remsberg, E. E.

    1985-01-01

    The Limb Infrared Monitor of the Stratospheric water vapor channel data analysis has been extended from the 1. mb level (about 48 km) to the .3 mb level (about 60 km) through a radiance averaging procedure and better understanding of systematic errors. The data show H2O mixing ratio peaks near the .5 mb level varying from 4 to 7 ppmv with latitude and season. Above this level the mixing ratio drops off quickly with altitude, but, due to experimental uncertainties, at an uncertain rate. The stratospheric results are virtually the same as determined from the archived LIMS results with a tropical hygropause and enhanced H2O concentration in the lower levels at high winter latitudes.

  16. National water resource management as a global problem: The example of Egypt

    Science.gov (United States)

    Elshorbagy, A. A.; Abdelkader, A. A.; Tuninetti, M.; Laio, F.; Ridolfi, L.; Fahmy, H.

    2017-12-01

    The engineering redistribution of water remains limited in its spatial scope, when compared with the socioeconomic redistribution of water in its virtual form. Virtual water (VW) embedded in products has its own human-induced cycle by moving across the globe. There is a significant body of literature on global VW trade networks (VWTN), with most studies focused on the network structure and the variables controlling its behavior. It was shown that the importing nations will play an important role in the evolution of the network dynamics. The increased connectivity of the global network highlights the risk of systemic disruptions and the vulnerability of the global food, especially when exporting countries change to non-exporting ones. The existing models of VWTN characterize the properties of the network, along with its nodes and links. Acknowledging its contribution to understand the global redistribution of virtual water, hardly can this approach attract potential users to adopt it. The VW trade (VWT) modeling needs to be repositioned to allow resource managers and policy makers at various scales to benefit from it and link global VW dynamics to their local decisions. The aim of this research is to introduce a new modeling approach for the VWT where detailed national scale water management is nested within the coarser global VWTN. The case study of Egypt, the world biggest importer of wheat, is considered here because its population growth and limitations of water and arable land position it as a significant node in the global network. A set of potential scenarios of Egypt's future, driven by population growth, development plans, consumption patterns, technology change, and water availability are developed. The annual national food and water balance in every scenario is calculated to estimate the potential for VW export and import of Egypt. The results indicate that Egypt's demand for food might cause unexpectedly higher demands on other countries' water resources

  17. Achieving sustainable irrigation water withdrawals: global impacts on food security and land use

    Science.gov (United States)

    Liu, Jing; Hertel, Thomas W.; Lammers, Richard B.; Prusevich, Alexander; Baldos, Uris Lantz C.; Grogan, Danielle S.; Frolking, Steve

    2017-10-01

    Unsustainable water use challenges the capacity of water resources to ensure food security and continued growth of the economy. Adaptation policies targeting future water security can easily overlook its interaction with other sustainability metrics and unanticipated local responses to the larger-scale policy interventions. Using a global partial equilibrium grid-resolving model SIMPLE-G, and coupling it with the global Water Balance Model, we simulate the consequences of reducing unsustainable irrigation for food security, land use change, and terrestrial carbon. A variety of future (2050) scenarios are considered that interact irrigation productivity with two policy interventions— inter-basin water transfers and international commodity market integration. We find that pursuing sustainable irrigation may erode other development and environmental goals due to higher food prices and cropland expansion. This results in over 800 000 more undernourished people and 0.87 GtC additional emissions. Faster total factor productivity growth in irrigated sectors will encourage more aggressive irrigation water use in the basins where irrigation vulnerability is expected to be reduced by inter-basin water transfer. By allowing for a systematic comparison of these alternative adaptations to future irrigation vulnerability, the global gridded modeling approach offers unique insights into the multiscale nature of the water scarcity challenge.

  18. Assessment of Salicylic Acid Impacts on Seedling Characteristic of Cucumber (Cucumis sativus L. under Water Stress

    Directory of Open Access Journals (Sweden)

    Hossein MARDANI

    2012-02-01

    Full Text Available Impacts of various concentrations of salicylic acid (SA on cucumber (Cucumis sativus L. seedling characteristic were evaluated under different water stress levels by using a factorial arrangement based on completely randomized design with three replications at experimental greenhouse of Ferdowsi University of Mashhad, Iran. The studied factors included three water deficit levels (100% FC, 80% FC, and 60% FC considered as first factor and five levels of SA concentrations (0, 0.25, 0.5, 0.75, and 1 mM as second factor. Results showed that foliar application of SA at the highest concentration enhanced leaf area, leaf and dry weight while decreased stomatal conductance under high level of water deficit stress. Though, severe water deficit stress sharply raised the SPAD reading values. In general, exogenous SA application could develop cucumber seedling characteristic and improve water stress tolerance.

  19. Rehydration After Water Stress in Forager Workers of Coptotermes gestroi (Wasmann) (Blattaria: Rhinotermitidae).

    Science.gov (United States)

    Janei, V; Lima, J T; Costa-Leonardo, A M

    2015-06-01

    Water maintenance is vital for termite survival under dry conditions, hence environment humidity is one of the most important factors that controls the distribution of Isoptera. To understand the dynamics of termite rehydration after water loss, two bioassays were performed with forager workers of Coptotermes gestroi (Wasmann) submitted to water stress. Insects were weighed and placed into Petri dishes without water and food for periods of 3, 15, and 30 h. For each period of water stress, 10 replicates were performed in the treatment and control groups, totalling 120 experimental units. Forager workers lost body mass across all periods of water stress and tested with the highest reduction for the 30 h exposure period. Subsequent access to water resulted in termite rehydration, and final weight values were near to initial body mass values. These results demonstrate that workers of C. gestroi experienced large reductions of body mass under water stress, but these reductions were not severe enough to cause mortality. Additionally, termites were able to rehydrate after water stress conditions. This is a potential risk factor to be considered in cases of new infestations because C. gestroi workers will be able to cause economic damage in their new locations even when deprived of water during their transportation by humans.

  20. Water-stress-induced breakdown of carbon-water relations: indicators from diurnal FLUXNET patterns

    Science.gov (United States)

    Nelson, Jacob A.; Carvalhais, Nuno; Migliavacca, Mirco; Reichstein, Markus; Jung, Martin

    2018-04-01

    Understanding of terrestrial carbon and water cycles is currently hampered by an uncertainty in how to capture the large variety of plant responses to drought. In FLUXNET, the global network of CO2 and H2O flux observations, many sites do not uniformly report the ancillary variables needed to study drought response physiology. To this end, we outline two data-driven indicators based on diurnal energy, water, and carbon flux patterns derived directly from the eddy covariance data and based on theorized physiological responses to hydraulic and non-stomatal limitations. Hydraulic limitations (i.e. intra-plant limitations on water movement) are proxied using the relative diurnal centroid (CET*), which measures the degree to which the flux of evapotranspiration (ET) is shifted toward the morning. Non-stomatal limitations (e.g. inhibitions of biochemical reactions, RuBisCO activity, and/or mesophyll conductance) are characterized by the Diurnal Water-Carbon Index (DWCI), which measures the degree of coupling between ET and gross primary productivity (GPP) within each day. As a proof of concept we show the response of the metrics at six European sites during the 2003 heat wave event, showing a varied response of morning shifts and decoupling. Globally, we found indications of hydraulic limitations in the form of significantly high frequencies of morning-shifted days in dry/Mediterranean climates and savanna/evergreen plant functional types (PFTs), whereas high frequencies of decoupling were dominated by dry climates and grassland/savanna PFTs indicating a prevalence of non-stomatal limitations in these ecosystems. Overall, both the diurnal centroid and DWCI were associated with high net radiation and low latent energy typical of drought. Using three water use efficiency (WUE) models, we found the mean differences between expected and observed WUE to be -0.09 to 0.44 µmol mmol-1 and -0.29 to -0.40 µmol mmol-1 for decoupled and morning-shifted days, respectively, compared

  1. Blended 6-Hourly Sea Surface Wind Vectors and Wind Stress on a Global 0.25 Degree Grid (1987-2011)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Blended Global Sea Surface Winds products contain ocean surface wind vectors and wind stress on a global 0.25 degree grid, in multiple time resolutions of...

  2. Reported Exposure and Emotional Reactivity to Daily Stressors: The Roles of Adult-Age and Global Perceived Stress

    Science.gov (United States)

    Stawski, Robert S.; Sliwinski, Martin J.; Almeida, David M.; Smyth, Joshua M.

    2012-01-01

    A central goal of daily stress research is to identify resilience and vulnerability factors associated with exposure and reactivity to daily stressors. The current study examined how age differences and global perceptions of stress relate to exposure and emotional reactivity to daily stressors. Sixty-seven younger (Mage = 20) and 116 older (Mage = 80) adults completed a daily stress diary and measures of positive and negative affect on 6 days over a 14 day period. Participants also completed a measure of global perceived stress. Results revealed that reported exposure to daily stressors is reduced in old age, but that emotional reactivity to daily stressors did not differ between young and older adults. Global perceived stress was associated with greater reported exposure to daily stressors in old adults, and greater stress-related increases in negative affect in younger adults. Furthermore, across days on which daily stressors were reported, intraindividual variability in the number and severity of stressors reported was associated with increased negative affect, but only among younger adults. PMID:18361654

  3. Reported exposure and emotional reactivity to daily stressors: the roles of adult age and global perceived stress.

    Science.gov (United States)

    Stawski, Robert S; Sliwinski, Martin J; Almeida, David M; Smyth, Joshua M

    2008-03-01

    A central goal of daily stress research is to identify resilience and vulnerability factors associated with exposure and reactivity to daily stressors. The present study examined how age differences and global perceptions of stress relate to exposure and emotional reactivity to daily stressors. Sixty-seven younger (M age = 20) and 116 older (M age = 80) adults completed a daily stress diary and measures of positive and negative affect on 6 days over a 14-day period. Participants also completed a measure of global perceived stress. Results revealed that reported exposure to daily stressors is reduced in old age but that emotional reactivity to daily stressors did not differ between younger and older adults. Global perceived stress was associated with greater reported exposure to daily stressors in older adults and greater stress-related increases in negative affect in younger adults. Furthermore, across days on which daily stressors were reported, intraindividual variability in the number and severity of stressors reported was associated with increased negative affect, but only among younger adults. (c) 2008 APA, all rights reserved.

  4. Water stress projections for the northeastern and Midwestern United States in 2060: anthropogenic and ecological consequences

    Science.gov (United States)

    Brian G. Tavernia; Mark D. Nelson; Peter Caldwell; Ge Sun

    2013-01-01

    Future climate and land-use changes and growing human populations may reduce the abundance of water resources relative to anthropogenic and ecological needs in the Northeast and Midwest (U.S.). We used output from WaSSI, a water accounting model, to assess potential changes between 2010 and 2060 in (1) anthropogenic water stress for watersheds throughout the Northeast...

  5. Effects of water stress on photosynthetic electron transport, photophosphorylation, and metabolite levels of Xanthium strumarium mesophyll cells.

    Science.gov (United States)

    Sharkey, T D; Badger, M R

    1982-12-01

    Several component processes of photosynthesis were measured in osmotically stressed mesophyll cells of Xanthium strumarium L. The ribulose-1,5-bisphosphate regeneration capacity was reduced by water stress. Photophoshorylation was sensitive to water stress but photosynthetic electron transport was unaffected by water potentials down to-40 bar (-4 MPa). The concentrations of several intermediates of the photosynthetic carbon-reduction cycle remained relatively constant and did not indicate that ATP supply was limiting photosynthesis in the water-stressed cells.

  6. Spiraling pathways of global deep waters to the surface of the Southern Ocean

    OpenAIRE

    Tamsitt, Veronica; Drake, Henri F.; Morrison, Adele K.; Talley, Lynne D.; Dufour, Carolina O.; Gray, Alison R.; Griffies, Stephen M.; Mazloff, Matthew R.; Sarmiento, Jorge L.; Wang, Jinbo; Weijer, Wilbert

    2017-01-01

    Upwelling of global deep waters to the sea surface in the Southern Ocean closes the global overturning circulation and is fundamentally important for oceanic uptake of carbon and heat, nutrient resupply for sustaining oceanic biological production, and the melt rate of ice shelves. However, the exact pathways and role of topography in Southern Ocean upwelling remain largely unknown. Here we show detailed upwelling pathways in three dimensions, using hydrographic observations and particle trac...

  7. Water insecurity in a syndemic context: Understanding the psycho-emotional stress of water insecurity in Lesotho, Africa.

    Science.gov (United States)

    Workman, Cassandra L; Ureksoy, Heather

    2017-04-01

    Syndemics occur when populations experience synergistic and multiplicative effects of co-occurring epidemics. Proponents of syndemic theory highlight the importance of understanding the social context in which diseases spread and cogently argue that there are biocultural effects of external stresses such as food insecurity and water insecurity. Thus, a holistic understanding of disease or social vulnerability must incorporate an examination of the emotional and social effects of these phenomena. This paper is a response to the call for a renewed focus on measuring the psycho-emotional and psychosocial effects of food insecurity and water insecurity. Using a mixed-method approach of qualitative interviews and quantitative assessment, including a household demographic, illness, and water insecurity scale, the Household Food Insecurity Access Scale, and the Hopkins Symptoms Checklist-25, this research explored the psycho-emotional effects of water insecurity, food insecurity, and household illness on women and men residing in three low-land districts in Lesotho (n = 75). Conducted between February and November of 2011, this exploratory study first examined the complicated interaction of water insecurity, food insecurity and illness to understand and quantify the relationship between these co-occurring stresses in the context of HIV/AIDS. Second, it sought to separate the role of water insecurity in predicting psycho-emotional stress from other factors, such as food insecurity and household illness. When asked directly about water, qualitative research revealed water availability, access, usage amount, and perceived water cleanliness as important dimensions of water insecurity, creating stress in respondents' daily lives. Qualitative and quantitative data show that water insecurity, food insecurity and changing household demographics, likely resulting from the HIV/AIDS epidemic, are all associated with increased anxiety and depression, and support the conclusion that

  8. Globalization

    OpenAIRE

    Andru?cã Maria Carmen

    2013-01-01

    The field of globalization has highlighted an interdependence implied by a more harmonious understanding determined by the daily interaction between nations through the inducement of peace and the management of streamlining and the effectiveness of the global economy. For the functioning of the globalization, the developing countries that can be helped by the developed ones must be involved. The international community can contribute to the institution of the development environment of the gl...

  9. Global transcriptional profiling of Burkholderia pseudomallei under salt stress reveals differential effects on the Bsa type III secretion system

    Directory of Open Access Journals (Sweden)

    Singsuksawat Ekapot

    2010-06-01

    Full Text Available Abstract Background Burkholderia pseudomallei is the causative agent of melioidosis where the highest reported incidence world wide is in the Northeast of Thailand, where saline soil and water are prevalent. Moreover, recent reports indicate a potential pathogenic role for B. pseudomallei in cystic fibrosis lung disease, where an increased sodium chloride (NaCl concentration in airway surface liquid has been proposed. These observations raise the possibility that high salinity may represent a favorable niche for B. pseudomallei. We therefore investigated the global transcriptional response of B. pseudomallei to increased salinity using microarray analysis. Results Transcriptome analysis of B. pseudomallei under salt stress revealed several genes significantly up-regulated in the presence of 320 mM NaCl including genes associated with the bsa-derived Type III secretion system (T3SS. Microarray data were verified by reverse transcriptase-polymerase chain reactions (RT-PCR. Western blot analysis confirmed the increased expression and secretion of the invasion-associated type III secreted proteins BipD and BopE in B. pseudomallei cultures at 170 and 320 mM NaCl relative to salt-free medium. Furthermore, salt-treated B. pseudomallei exhibited greater invasion efficiency into the lung epithelial cell line A549 in a manner partly dependent on a functional Bsa system. Conclusions B. pseudomallei responds to salt stress by modulating the transcription of a relatively small set of genes, among which is the bsa locus associated with invasion and virulence. Expression and secretion of Bsa-secreted proteins was elevated in the presence of exogenous salt and the invasion efficiency was enhanced. Our data indicate that salinity has the potential to influence the virulence of B. pseudomallei.

  10. Global water cycle amplifying at less than the Clausius-Clapeyron rate

    OpenAIRE

    Skliris, Nikolaos; Zika, Jan D.; Nurser, George; Josey, Simon A.; Marsh, Robert

    2016-01-01

    A change in the cycle of water from dry to wet regions of the globe would have far reaching impact on humanity. As air warms, its capacity to hold water increases at the Clausius-Clapeyron rate (CC, approximately 7%?°C?1). Surface ocean salinity observations have suggested the water cycle has amplified at close to CC following recent global warming, a result that was found to be at odds with state-of the art climate models. Here we employ a method based on water mass transformation theory for...

  11. Global Energy and Water Cycle Experiment (GEWEX) and the Continental-scale International Project (GCIP)

    Science.gov (United States)

    Vane, Deborah

    1993-01-01

    A discussion of the objectives of the Global Energy and Water Cycle Experiment (GEWEX) and the Continental-scale International Project (GCIP) is presented in vugraph form. The objectives of GEWEX are as follows: determine the hydrological cycle by global measurements; model the global hydrological cycle; improve observations and data assimilation; and predict response to environmental change. The objectives of GCIP are as follows: determine the time/space variability of the hydrological cycle over a continental-scale region; develop macro-scale hydrologic models that are coupled to atmospheric models; develop information retrieval schemes; and support regional climate change impact assessment.

  12. Gas exchange and hydraulics in seedlings of Hevea brasiliensis during water stress and recovery.

    Science.gov (United States)

    Chen, Jun-Wen; Zhang, Qiang; Li, Xiao-Shuang; Cao, Kun-Fang

    2010-07-01

    The response of plants to drought has received significant attention, but far less attention has been given to the dynamic response of plants during recovery from drought. Photosynthetic performance and hydraulic capacity were monitored in seedlings of Hevea brasiliensis under water stress and during recovery following rewatering. Leaf water relation, gas exchange rate and hydraulic conductivity decreased gradually after water stress fell below a threshold, whereas instantaneous water use efficiency and osmolytes increased significantly. After 5 days of rewatering, leaf water relation, maximum stomatal conductance (g(s-max)) and plant hydraulic conductivity had recovered to the control levels except for sapwood area-specific hydraulic conductivity, photosynthetic assimilation rate and osmolytes. During the phase of water stress, stomata were almost completely closed before water transport efficiency decreased substantially, and moreover, the leaf hydraulic pathway was more vulnerable to water stress-induced embolism than the stem hydraulic pathway. Meanwhile, g(s-max) was linearly correlated with hydraulic capacity when water stress exceeded a threshold. In addition, a positive relationship was shown to occur between the recovery of g(s-max) and of hydraulic capacity during the phase of rewatering. Our results suggest (i) that stomatal closure effectively reduces the risk of xylem dysfunction in water-stressed plants at the cost of gas exchange, (ii) that the leaf functions as a safety valve to protect the hydraulic pathway from water stress-induced dysfunction to a larger extent than does the stem and (iii) that the full drought recovery of gas exchange is restricted by not only hydraulic factors but also non-hydraulic factors.

  13. Effects of Nutrients Foliar Application on Agrophysiological Characteristics of Maize under Water Deficit Stress

    Directory of Open Access Journals (Sweden)

    Nour Ali SAJEDI

    2010-09-01

    Full Text Available To investigate effects of nutrients foliar application on agrophysiological characteristics of maize hybrid �KSC 704� water deficit stress conditions, an experiment was arranged in a split plot factorial based on a randomized complete block design with four replications to the Research Station of Islamic Azad University-Arak Branch, Iran in 2007-2008. Main factors studied were four irrigation levels including irrigation equal to crop water requirement, water deficit stress at eight-leaf stage (V8, blister stage (R2 and filling grain stage (R4 in the main plot. Combined levels of selenium treatment (without and with application 20 gha-1 and micronutrients (without and with application 2 lha-1 were situated in sub plots. Results showed that water deficit stress decreased grain yield 19.7% in blister stage as compared with control. Using selenium increased relative content water at R2 and R4 stages significantly. Using selenium in water deficit stress condition increased measured traits except plant height as compared with treatment without selenium. A negative antagonistic interaction was found between selenium and micronutrients on some measured traits. Between treatments of water deficit stress, highest grain yield equal 6799.52 and 6736.97 kgha-1 was obtained from combined treatments of water deficit stress at eight-leaf stage+without selenium+without micronutrients and water deficit stress at eight-leaf stage+selenium+without micronutrients respectively which compared with treatment of irrigation equal to crop water requirement+selenium+microelements did not differ significant. According to the results of experiment, it is concluded that with micronutrients fertilizer spray under optimum irrigation and selenium spray under water deficit obtain optimum yield.

  14. Fundamental approaches to predicting stress corrosion: 'Quantitative micro-nano' (QMN) approach to predicting stress corrosion cracking in water cooled nuclear plants

    International Nuclear Information System (INIS)

    Staehle, R.W.

    2010-01-01

    This paper describes the modeling and experimental studies of stress corrosion cracking with full disciplinary set at the atomic level. Its objective is to develop an intellectual structure for quantitative prediction of stress corrosion cracking in water cooled reactors.

  15. How close do we live to water? A global analysis of population distance to freshwater bodies.

    Directory of Open Access Journals (Sweden)

    Matti Kummu

    Full Text Available Traditionally, people have inhabited places with ready access to fresh water. Today, over 50% of the global population lives in urban areas, and water can be directed via tens of kilometres of pipelines. Still, however, a large part of the world's population is directly dependent on access to natural freshwater sources. So how are inhabited places related to the location of freshwater bodies today? We present a high-resolution global analysis of how close present-day populations live to surface freshwater. We aim to increase the understanding of the relationship between inhabited places, distance to surface freshwater bodies, and climatic characteristics in different climate zones and administrative regions. Our results show that over 50% of the world's population lives closer than 3 km to a surface freshwater body, and only 10% of the population lives further than 10 km away. There are, however, remarkable differences between administrative regions and climatic zones. Populations in Australia, Asia, and Europe live closest to water. Although populations in arid zones live furthest away from freshwater bodies in absolute terms, relatively speaking they live closest to water considering the limited number of freshwater bodies in those areas. Population distributions in arid zones show statistically significant relationships with a combination of climatic factors and distance to water, whilst in other zones there is no statistically significant relationship with distance to water. Global studies on development and climate adaptation can benefit from an improved understanding of these relationships between human populations and the distance to fresh water.

  16. Hydraulic failure defines the recovery and point of death in water-stressed conifers.

    Science.gov (United States)

    Brodribb, Tim J; Cochard, Hervé

    2009-01-01

    This study combines existing hydraulic principles with recently developed methods for probing leaf hydraulic function to determine whether xylem physiology can explain the dynamic response of gas exchange both during drought and in the recovery phase after rewatering. Four conifer species from wet and dry forests were exposed to a range of water stresses by withholding water and then rewatering to observe the recovery process. During both phases midday transpiration and leaf water potential (Psileaf) were monitored. Stomatal responses to Psileaf were established for each species and these relationships used to evaluate whether the recovery of gas exchange after drought was limited by postembolism hydraulic repair in leaves. Furthermore, the timing of gas-exchange recovery was used to determine the maximum survivable water stress for each species and this index compared with data for both leaf and stem vulnerability to water-stress-induced dysfunction measured for each species. Recovery of gas exchange after water stress took between 1 and >100 d and during this period all species showed strong 1:1 conformity to a combined hydraulic-stomatal limitation model (r2 = 0.70 across all plants). Gas-exchange recovery time showed two distinct phases, a rapid overnight recovery in plants stressed to 50% loss of Kleaf. Maximum recoverable water stress (Psimin) corresponded to a 95% loss of Kleaf. Thus, we conclude that xylem hydraulics represents a direct limit to the drought tolerance of these conifer species.

  17. Nondestructive detection of water stress in tomato [Lycopersicon esculentum] plants using microwave sensing, 2

    International Nuclear Information System (INIS)

    Shimomachi, T.; Takemasa, T.; Kurata, K.; Takakura, T.

    2004-01-01

    The physiological accommodation response to environmental stress of a plant can induce changes in physiological and physical conditions of the plant. These changes influence the dielectric properties of the plant, which can be detected by measuring microwave complex dielectric properties of plant materials such as leaves and stems. The objective of this research was to detect these responses of plants to water deficiency stress nondestructively. The complex dielectric properties of tomato leaves during water stress were measured with an Open-ended Coaxial Probe from 0.3 to 3 GHz, as well as changes in gravimetric moisture, photosynthetic rate, stomatal conductance and water potential which reflect the physiological condition of the plants. Experimental results showed that the complex permittivity (both permittivity and loss factor) of tomato leaves increased during water stress. Of the parameters measured the highest correlation was observed between complex permittivity and water potential. In order to confirm these results, control and water deficient tomato leaves were crushed, and the complex permittivity was measured and compared. The results showed quite similar tendencies compared with the results from the nondestructive microwave measurements. A physiochemical model to describe the complex permittivity of crushed non-stressed and stressed tomato leaves was constructed with pure water, pulp, glycine, and KN03, and the complex dielectric measurements of crushed tomato leaves were reproduced quite accurately from 0.3 to 3 GHz

  18. Mapping global surface water inundation dynamics using synergistic information from SMAP, AMSR2 and Landsat

    Science.gov (United States)

    Du, J.; Kimball, J. S.; Galantowicz, J. F.; Kim, S.; Chan, S.; Reichle, R. H.; Jones, L. A.; Watts, J. D.

    2017-12-01

    A method to monitor global land surface water (fw) inundation dynamics was developed by exploiting the enhanced fw sensitivity of L-band (1.4 GHz) passive microwave observations from the Soil Moisture Active Passive (SMAP) mission. The L-band fw (fwLBand) retrievals were derived using SMAP H-polarization brightness temperature (Tb) observations and predefined L-band reference microwave emissivities for water and land endmembers. Potential soil moisture and vegetation contributions to the microwave signal were represented from overlapping higher frequency Tb observations from AMSR2. The resulting fwLBand global record has high temporal sampling (1-3 days) and 36-km spatial resolution. The fwLBand annual averages corresponded favourably (R=0.84, pretrievals showed favourable classification accuracy for water (commission error 31.84%; omission error 28.08%) and land (commission error 0.82%; omission error 0.99%) and seasonal wet and dry periods when compared to independent water maps derived from Landsat-8 imagery. The new fwLBand algorithms and continuing SMAP and AMSR2 operations provide for near real-time, multi-scale monitoring of global surface water inundation dynamics, potentially benefiting hydrological monitoring, flood assessments, and global climate and carbon modeling.

  19. Adapting to Water Stress in the Comahue Region of Argentina ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    , quality, and distribution -generate local and regional climate and hydrological models and scenarios for mid- and long-term water availability -assess current water availability, use, and distribution in sub-regions of the Comahue and provide ...

  20. Effects of water stress and seed mass on germination and ...

    African Journals Online (AJOL)

    enoh

    2012-03-01

    Mar 1, 2012 ... polyvinylpyrrolidone; TCA, trichloroacetic acid; NBT, nitroblue tetrazolium; TBA ..... seeds had weaker resistances to moderate stress (-0.6. MPa) compared with .... Chen YN,Chen YP,Li WH,Zhang HF (2003). Response of ...

  1. Effects of salinity stress on water uptake, germination and early ...

    African Journals Online (AJOL)

    Administrator

    2011-09-07

    Sep 7, 2011 ... Department of Field Crops, Faculty of Agriculture, Namik Kemal University, 59100 Tekirdag, ..... stresses on germination in durum wheat (Triticum durum Desf.) .... transgenic perennial ryegrass (Lolium perenne L.) obtained by.

  2. Global Water Cycle Agreement in the Climate Models Assessed in the IPCC AR4

    Science.gov (United States)

    Waliser, D.; Seo, K. -W.; Schubert, S.; Njoku, E.

    2007-01-01

    This study examines the fidelity of the global water cycle in the climate model simulations assessed in the IPCC Fourth Assessment Report. The results demonstrate good model agreement in quantities that have had a robust global observational basis and that are physically unambiguous. The worst agreement occurs for quantities that have both poor observational constraints and whose model representations can be physically ambiguous. In addition, components involving water vapor (frozen water) typically exhibit the best (worst) agreement, and fluxes typically exhibit better agreement than reservoirs. These results are discussed in relation to the importance of obtaining accurate model representation of the water cycle and its role in climate change. Recommendations are also given for facilitating the needed model improvements.

  3. Dynamic modelling of water demand, water availability and adaptation strategies for power plants to global change

    International Nuclear Information System (INIS)

    Koch, Hagen; Voegele, Stefan

    2009-01-01

    According to the latest IPCC reports, the frequency of hot and dry periods will increase in many regions of the world in the future. For power plant operators, the increasing possibility of water shortages is an important challenge that they have to face. Shortages of electricity due to water shortages could have an influence on industries as well as on private households. Climate change impact analyses must analyse the climate effects on power plants and possible adaptation strategies for the power generation sector. Power plants have lifetimes of several decades. Their water demand changes with climate parameters in the short- and medium-term. In the long-term, the water demand will change as old units are phased out and new generating units appear in their place. In this paper, we describe the integration of functions for the calculation of the water demand of power plants into a water resources management model. Also included are both short-term reactive and long-term planned adaptation. This integration allows us to simulate the interconnection between the water demand of power plants and water resources management, i.e. water availability. Economic evaluation functions for water shortages are also integrated into the water resources management model. This coupled model enables us to analyse scenarios of socio-economic and climate change, as well as the effects of water management actions. (author)

  4. Effect of water stress on in vitro mycelium cultures of two mycorrhizal desert truffles.

    Science.gov (United States)

    Navarro-Ródenas, Alfonso; Lozano-Carrillo, M Cecilia; Pérez-Gilabert, Manuela; Morte, Asunción

    2011-05-01

    The ability of two species of desert truffle, Terfezia claveryi strain TcS2 and Picoa lefebvrei strain OL2, to tolerate water stress in pure culture has been investigated. Both T. claveryi and P. lefebvrei strains exhibited a mycelium growth pattern characteristic of drought tolerant species. However, they were only tolerant to moderate water stress, below -1.07 MPa, with the P. lefebvrei isolate being slightly more drought tolerant than the T. claveryi isolate. The increased alkaline phosphatase (ALP) activity observed in both fungi at moderate water stress with respect to the control indicated the functional adaptation of these mycelia to these drought conditions. ALP activity can be used as an indicator of the metabolic activity of these fungi. Slight water stress (-0.45 MPa) could improve mycelial inoculum production of these desert truffles. Moreover, P. lefebvrei could be a good candidate for further desert truffle mycorrhizal plant cultivation programmes in semiarid Mediterranean areas.

  5. Stress corrosion cracking of equipment materials in domestic pressurized water reactors and the relevant safety management

    International Nuclear Information System (INIS)

    Sun Haitao

    2015-01-01

    International and domestic research and project state about stress corrosion cracking of nuclear equipments and materials (including austenitic stainless steel and nickel based alloys) in pressurized water reactor are discussed, and suggestions on how to prevent, mitigate ana deal with the stress corrosion cracking issues in domestic reactors are given in this paper based on real case analysis and study ondomestic nuclear equipment and material stress corrosion cracking failure. (author)

  6. Effect of Water Deficit Stress on Peach Growth under Commercial Orchard Management Conditions

    Directory of Open Access Journals (Sweden)

    M. Rahmati

    2015-06-01

    Full Text Available In order to study the sensitivity of vegetative growth to water deficit stress of a late-maturing peach (Prunus persica L. cv. Elberta under orchard conditions, an experiment was conducted as randomized complete-block design with three treatments and four repetitions in Shahdiran commercial orchard in Mashhad during 2011. Three irrigation treatments including 360 (low stress, 180 (moderate stress and 90 (severe stress m3ha-1week-1 using a drip irrigation system (minimum stem water potential near harvest: -1.2, -1.5 and -1.7 MPa, respectively from the mid-pit hardening stage (12th of June until harvest (23rd of Sep. applied. Predawn, stem and leaf water potentials, leaf photosynthesis, transpiration, stomatal conductance and leaf temperature, the number of new shoots on fruit bearing shoots and vegetative shoots lengths during growing season as well as leaf area at harvest were measured. The results showed that water deficit stress had negative effects on peach tree water status, thereby resulting in decreased leaf gas exchange and tree vegetative growth. As significant decreased assimilate production of tree was resulted from both decreased leaf assimilation rate (until about 23 % and 50 %, respectively under moderate and severe stress conditions compared to low stress conditions and decreased leaf area of tree (until about 57% and 79%, respectively under moderate and severe stress conditions compared to low stress conditions at harvest. The significant positive correlation between leaf water potential and vegetative growth of peach revealed that shoot growth would decrease by 30% and 50% of maximum at leaf water potential of –1.56 and –2.30 MPa, respectively.

  7. Water-energy nexus for urban water systems: A comparative review on energy intensity and environmental impacts in relation to global water risks

    International Nuclear Information System (INIS)

    Lee, Mengshan; Keller, Arturo A.; Chiang, Pen-Chi; Den, Walter; Wang, Hongtao; Hou, Chia-Hung; Wu, Jiang; Wang, Xin; Yan, Jinyue

    2017-01-01

    Highlights: •This study quantifies the nexus as energy intensity and greenhouse gas potential. •Baseline water stress and return flow ratio are identified as water risks. •Source water accessibility significantly contributes to variations in the nexus. •Water risks have little impact on the nexus of wastewater systems. •Study on the nexus is suggested to be conducted at regional levels. -- Abstract: The importance of the interdependence between water and energy, also known as the water-energy nexus, is well recognized. The water-energy nexus is typically characterized in resource use efficiency terms such as energy intensity. This study aims to explore the quantitative results of the nexus in terms of energy intensity and environmental impacts (mainly greenhouse gas emissions) on existing water systems within urban water cycles. We also characterized the influence of water risks on the water-energy nexus, including baseline water stress (a water quantity indicator) and return flow ratio (a water quality indicator). For the 20 regions and 4 countries surveyed (including regions with low to extremely high water risks that are geographically located in Africa, Australia, Asia, Europe, and North America), their energy intensities were positively related to the water risks. Regions with higher water risks were observed to have relatively higher energy and GHG intensities associated with their water supply systems. This mainly reflected the major influence of source water accessibility on the nexus, particularly for regions requiring energy-intensive imported or groundwater supplies, or desalination. Regions that use tertiary treatment (for water reclamation or environmental protection) for their wastewater treatment systems also had relatively higher energy and GHG emission intensities, but the intensities seemed to be independent from the water risks. On-site energy recovery (e.g., biogas or waste heat) in the wastewater treatment systems offered a great

  8. Physiological changes of pepper accessions in response to salinity and water stress

    Energy Technology Data Exchange (ETDEWEB)

    López-Serrano, L.; Penella, C.; San Bautista, A.; López-Galarza, S.; Calatayud, A.

    2017-07-01

    New sources of water stress and salinity tolerances are needed for crops grown in marginal lands. Pepper is considered one of the most important crops in the world. Many varieties belong to the genus Capsicum spp., and display wide variability in tolerance/sensitivity terms in response to drought and salinity stress. The objective was to screen seven salt/drought-tolerant pepper accessions to breed new cultivars that could overcome abiotic stresses, or be used as new crops in land with water and salinity stress. Fast and effective physiological traits were measured to achieve the objective. The present study showed wide variability of the seven pepper accessions in response to both stresses. Photosynthesis, stomatal conductance and transpiration reduced mainly under salinity due to stomatal and non-stomatal (Na+ accumulation) constraints and, to a lesser extent, in the accessions grown under water stress. A positive relationship between CO2 fixation and fresh weight generation was observed for both stresses. Decreases in Ys and YW and increased proline were observed only when accessions were grown under salinity. However, these factors were not enough to alleviate salt effects and an inverse relation was noted between plant salt tolerance and proline accumulation. Under water stress, A31 was the least affected and A34 showed the best tolerance to salinity in terms of photosynthesis and biomass.

  9. Metal balance shift induced in small fresh water fish by several environmental stresses

    International Nuclear Information System (INIS)

    Yukawa, Masae; Iso, Hiroyuki; Kodama, Kumiko; Imaseki, Hitoshi; Aoki, Kazuko; Ishikawa, Yuji

    2005-01-01

    Balance of essential elements in organisms might be changed by environmental stresses. Small fresh water fish, Medaka, was burdened with X-ray irradiation (total dose: 17 Gy), keeping in salty water (70% NaCl of sea water) and keeping in metal containing water (10 ppm of Cr and Co). These stresses are not lethal doses. Essential elements in liver, gall bladder, kidney, spleen, heart and brain in the stress-loaded fish were measured by PIXE method and compared with a control fish to determine the effect of the stresses. Various changes of the elemental contents were observed. Effect of X-ray irradiation was the smallest among the stresses. Relatively high content elements such as P, S, Cl and K were hardly affected with the stresses examined in this work. The effect of Cr on the metal balance seems to be larger than the other stresses. As PIXE method can analyze many elements in a small sample simultaneously, change of elemental distribution in small organisms induced by environmental stresses can be determined readily. (author)

  10. Physiological changes of pepper accessions in response to salinity and water stress

    International Nuclear Information System (INIS)

    López-Serrano, L.; Penella, C.; San Bautista, A.; López-Galarza, S.; Calatayud, A.

    2017-01-01

    New sources of water stress and salinity tolerances are needed for crops grown in marginal lands. Pepper is considered one of the most important crops in the world. Many varieties belong to the genus Capsicum spp., and display wide variability in tolerance/sensitivity terms in response to drought and salinity stress. The objective was to screen seven salt/drought-tolerant pepper accessions to breed new cultivars that could overcome abiotic stresses, or be used as new crops in land with water and salinity stress. Fast and effective physiological traits were measured to achieve the objective. The present study showed wide variability of the seven pepper accessions in response to both stresses. Photosynthesis, stomatal conductance and transpiration reduced mainly under salinity due to stomatal and non-stomatal (Na+ accumulation) constraints and, to a lesser extent, in the accessions grown under water stress. A positive relationship between CO2 fixation and fresh weight generation was observed for both stresses. Decreases in Ys and YW and increased proline were observed only when accessions were grown under salinity. However, these factors were not enough to alleviate salt effects and an inverse relation was noted between plant salt tolerance and proline accumulation. Under water stress, A31 was the least affected and A34 showed the best tolerance to salinity in terms of photosynthesis and biomass.

  11. Impacts of Climate Variability on the Spatio-temporal Characteristics of Water Stress in Korea

    Science.gov (United States)

    Kim, Soojun; Devineni, Naresh; Lall, Upmanu; Kim, Hung Soo

    2017-04-01

    This study intended to evaluate water stress quantitatively targeted at the Korean Peninsula and to analyze the spatial and temporal characteristics of its occurrence. First, the severity and multiyear influence of water stress were analyzed by realizing water balance based on water supply and demand and by calculating the normalized deficit index (NDI) and the normalized deficit cumulated (NDC) for 113 small basins in the Korean Peninsula. Next, a change in the periodic characteristics of water stress was analyzed using wavelet transform of the NDI by small basins and 3 bands of periods of 1 year, 2-4 years, and 4-8 years were separated. Through an analysis of the empirical orthogonal function (EOF) on each band, it was found that water stress occurring in the Korean Peninsula has the characteristics of spatial distribution that it is extended from the south coast to the northern area and inland as its period gets longer. An analysis of the band with a period of 2-8 years for water stress showed that it has a relationship with El Niño-Southern Oscillation (ENSO). Acknowledgment This research was supported by a grant (14AWMP-B082564-01) from Advanced Water Management Research Program funded by Ministry of Land, Infrastructure and Transport of Korean government.

  12. Evaluation of global water quality - the potential of a data- and model-driven analysis

    Science.gov (United States)

    Bärlund, Ilona; Flörke, Martina; Alcamo, Joseph; Völker, Jeanette; Malsy, Marcus; Kaus, Andrew; Reder, Klara; Büttner, Olaf; Katterfeld, Christiane; Dietrich, Désirée; Borchardt, Dietrich

    2016-04-01

    The ongoing socio-economic development presents a new challenge for water quality worldwide, especially in developing and emerging countries. It is estimated that due to population growth and the extension of water supply networks, the amount of waste water will rise sharply. This can lead to an increased risk of surface water quality degradation, if the wastewater is not sufficiently treated. This development has impacts on ecosystems and human health, as well as food security. The United Nations Member States have adopted targets for sustainable development. They include, inter alia, sustainable protection of water quality and sustainable use of water resources. To achieve these goals, appropriate monitoring strategies and the development of indicators for water quality are required. Within the pre-study for a 'World Water Quality Assessment' (WWQA) led by United Nations Environment Programme (UNEP), a methodology for assessing water quality, taking into account the above-mentioned objectives has been developed. The novelty of this methodology is the linked model- and data-driven approach. The focus is on parameters reflecting the key water quality issues, such as increased waste water pollution, salinization or eutrophication. The results from the pre-study show, for example, that already about one seventh of all watercourses in Latin America, Africa and Asia show high organic pollution. This is of central importance for inland fisheries and associated food security. In addition, it could be demonstrated that global water quality databases have large gaps. These must be closed in the future in order to obtain an overall picture of global water quality and to target measures more efficiently. The aim of this presentation is to introduce the methodology developed within the WWQA pre-study and to show selected examples of application in Latin America, Africa and Asia.

  13. Water deficit stress-induced changes in carbon and nitrogen partitioning in Chenopodium quinoa Willd.

    Science.gov (United States)

    Bascuñán-Godoy, Luisa; Reguera, Maria; Abdel-Tawab, Yasser M; Blumwald, Eduardo

    2016-03-01

    Water deficit stress followed by re-watering during grain filling resulted in the induction of the ornithine pathway and in changes in Quinoa grain quality. The genetic diversity of Chenopodium quinoa Willd. (Quinoa) is accompanied by an outstanding environmental adaptability and high nutritional properties of the grains. However, little is known about the biochemical and physiological mechanisms associated with the abiotic stress tolerance of Quinoa. Here, we characterized carbon and nitrogen metabolic changes in Quinoa leaves and grains in response to water deficit stress analyzing their impact on the grain quality of two lowland ecotypes (Faro and BO78). Differences in the stress recovery response were found between genotypes including changes in the activity of nitrogen assimilation-associated enzymes that resulted in differences in grain quality. Both genotypes showed a common strategy to overcome water stress including the stress-induced synthesis of reactive oxygen species scavengers and osmolytes. Particularly, water deficit stress induced the stimulation of the ornithine and raffinose pathways. Our results would suggest that the regulation of C- and N partitioning in Quinoa during grain filling could be used for the improvement of the grain quality without altering grain yields.

  14. Water and temperature stress define the optimal flowering period for wheat in south-eastern Australia

    OpenAIRE

    Evans, John; Kirkegaard, John; Hunt, James; Flohr, Bonnie

    2017-01-01

    Across the Australian wheat belt, the time at which wheat flowers is a critical determinant of yield. In all environments an optimal flowering period (OFP) exists which is defined by decreasing frost risk, and increasing water and heat stress. Despite their critical importance, OFPs have not been comprehensively defined across south eastern Australia′s (SEA) cropping zone using yield estimates incorporating temperature, radiation and water-stress. In this study, the widely validated cropping ...

  15. Nitrogen Metabolism in Adaptation of Photosynthesis to Water Stress in Rice Grown under Different Nitrogen Levels

    Directory of Open Access Journals (Sweden)

    Chu Zhong

    2017-06-01

    Full Text Available To investigate the role of nitrogen (N metabolism in the adaptation of photosynthesis to water stress in rice, a hydroponic experiment supplying with low N (0.72 mM, moderate N (2.86 mM, and high N (7.15 mM followed by 150 g⋅L-1 PEG-6000 induced water stress was conducted in a rainout shelter. Water stress induced stomatal limitation to photosynthesis at low N, but no significant effect was observed at moderate and high N. Non-photochemical quenching was higher at moderate and high N. In contrast, relative excessive energy at PSII level (EXC was declined with increasing N level. Malondialdehyde and hydrogen peroxide (H2O2 contents were in parallel with EXC. Water stress decreased catalase and ascorbate peroxidase activities at low N, resulting in increased H2O2 content and severer membrane lipid peroxidation; whereas the activities of antioxidative enzymes were increased at high N. In accordance with photosynthetic rate and antioxidative enzymes, water stress decreased the activities of key enzymes involving in N metabolism such as glutamate synthase and glutamate dehydrogenase, and photorespiratory key enzyme glycolate oxidase at low N. Concurrently, water stress increased nitrate content significantly at low N, but decreased nitrate content at moderate and high N. Contrary to nitrate, water stress increased proline content at moderate and high N. Our results suggest that N metabolism appears to be associated with the tolerance of photosynthesis to water stress in rice via affecting CO2 diffusion, antioxidant capacity, and osmotic adjustment.

  16. Proline accumulation in water-stressed barley leaves in relation to translocation and the nitrogen budget

    International Nuclear Information System (INIS)

    Tully, R.E.; Hanson, A.D.; Nelsen, C.E.

    1979-01-01

    Mobilization of N from leaves of barley (Hordeum vulgare L.) during water stress, and the role of proline as a mobilized species, were examined in plants at the three-leaf stage. The plants responded to water stress by withdrawing about 25% of the total reduced N from the leaf blades via phloem translocation. Most of this N loss was during the first 2 days while translocation of 14 C-photosynthate out of the stressed blade still remained active. Free proline accumulation in the blade was initially slow, and became more rapid during the 2nd day of stress. Although a major free amino acid, proline accounted for only about 5% of the total N(soluble + insoluble) retained in severely stressed blades. When the translocation pathway in water-stressed leaves was interrupted just below the blade by a heat girdle, a cold jacket, or by blade excision, N loss from the blade was prevented and proline began to accumulate rapidly on 1st day of stress. Little free proline accumulated in the blades until after the ability to translocate was lost. Proline was, however, probably not a major species of N translocated during stress, because proline N accumulation in heat-girdled stressed leaves was five times slower than the rate of total N export from intact blades

  17. Global SUMO proteome responses guide gene regulation, mRNA biogenesis, and plant stress responses

    Directory of Open Access Journals (Sweden)

    Magdalena eMazur

    2012-09-01

    Full Text Available Small-ubiquitin-like MOdifier (SUMO is a key regulator of abiotic stress, disease resistance and development in plants. The identification of >350 plant SUMO targets has revealed many processes modulated by SUMO and potential consequences of SUMO on its targets. Importantly, highly related proteins are SUMO-modified in plants, yeast, and metazoans. Overlapping SUMO targets include heat-shock proteins, transcription regulators, histones, histone-modifying enzymes, proteins involved in DNA damage repair, but also proteins involved in mRNA biogenesis and nucleo-cytoplasmic transport. Proteomics studies indicate key roles for SUMO in gene repression by controlling histone (deacetylation activity at genomic loci. The responsible heavily sumoylated transcriptional repressor complexes are recruited by EAR (Ethylene-responsive element binding factor [ERF]-associated Amphiphilic Repression-motif containing transcription factors in plants. These transcription factors are not necessarily themselves a SUMO target. Conversely, SUMO acetylation prevents binding of downstream partners by preventing binding of SIMs (SUMO-interaction peptide motifs presents in these partners, while SUMO acetylation has emerged as mechanism to recruit specifically bromodomains; bromodomain are generally linked with gene activation. These findings strengthen the idea of a bidirectional sumo-/acetylation switch in gene regulation. Quantitative proteomics has highlighted that global sumoylation provides a dynamic response to protein damage involving SUMO chain-mediated protein degradation, but also SUMO E3 ligase-dependent transcription of HSP (Heat-shock protein genes. With these insights in SUMO function and novel technical advancements, we can now study SUMO dynamics in responses to (abiotic stress in plants.

  18. Global costs and benefits of reaching universal coverage of sanitation and drinking-water supply.

    Science.gov (United States)

    Hutton, Guy

    2013-03-01

    Economic evidence on the cost and benefits of sanitation and drinking-water supply supports higher allocation of resources and selection of efficient and affordable interventions. The study aim is to estimate global and regional costs and benefits of sanitation and drinking-water supply interventions to meet the Millennium Development Goal (MDG) target in 2015, as well as to attain universal coverage. Input data on costs and benefits from reviewed literature were combined in an economic model to estimate the costs and benefits, and benefit-cost ratios (BCRs). Benefits included health and access time savings. Global BCRs (Dollar return per Dollar invested) were 5.5 for sanitation, 2.0 for water supply and 4.3 for combined sanitation and water supply. Globally, the costs of universal access amount to US$ 35 billion per year for sanitation and US$ 17.5 billion for drinking-water, over the 5-year period 2010-2015 (billion defined as 10(9) here and throughout). The regions accounting for the major share of costs and benefits are South Asia, East Asia and sub-Saharan Africa. Improved sanitation and drinking-water supply deliver significant economic returns to society, especially sanitation. Economic evidence should further feed into advocacy efforts to raise funding from governments, households and the private sector.

  19. Assessing the impact of global changes on the surface water resources of Southwestern Nigeria

    CSIR Research Space (South Africa)

    Ayeni, AO

    2014-12-01

    Full Text Available Understanding the relative impact of land use, land cover and climate change (LULCC) on basin runoff is necessary in assessing basin water stress. This assessment requires long-term observed rainfall time series and land-use/land-cover (LULC...

  20. The Global Dimension of Water Governance: Why the River Basin Approach Is No Longer Sufficient and Why Cooperative Action at Global Level Is Needed

    Directory of Open Access Journals (Sweden)

    Arjen Y. Hoekstra

    2010-12-01

    Full Text Available When water problems extend beyond the borders of local communities, the river basin is generally seen as the most appropriate unit for analysis, planning, and institutional arrangements. In this paper it is argued that addressing water problems at the river basin level is not always sufficient. Many of today’s seemingly local water issues carry a (subcontinental or even global dimension, which urges for a governance approach that comprises institutional arrangements at a level beyond that of the river basin. This paper examines a number of arguments for the thesis that good water governance requires a global approach complementary to the river basin approach. Subsequently, it identifies four major issues to be addressed at global scale: Efficiency, equity, sustainability and security of water supply in a globalised world. Finally, the paper raises the question of what kind of institutional arrangements could be developed to cope with the global dimension of water issues. A few possible directions are explored, ranging from an international protocol on full-cost water pricing and a water label for water-intensive products to the implementation of water footprint quotas and the water-neutral concept.

  1. A global assessment of wildfire risks to human and environmental water security

    Science.gov (United States)

    Robinne, François-Nicolas; Parisien, Marc-André; Flannigan, Mike; Miller, Carol; Bladon, Kevin D.

    2017-04-01

    Extreme wildfire events extensively affect hydrosystem stability and generate an important threat to the reliability of the water supply for human and natural communities. While actively studied at the watershed scale, the development of a global vision of wildfire risk to water security has only been undertaken recently, pointing at potential water security concerns in an era of global changes. In order to address this concern, we propose a global-scale analysis of the wildfire risk to surface water supplies based on the Driving forces-Pressures-States-Impacts-Responses (DPSIR) framework. This framework relies on the cause-and-effect relationships existing between the five categories of the DPSIR chain. Based on the literature, we gathered an extensive set of spatial indicators relevant to fire-induced hydrological hazards and water consumption patterns by human and natural communities. Each indicator was assigned a DPSIR category. Then, we collapsed the information in each category using a principal component analysis in order to extract the most relevant pixel-based information provided by each spatial indicator. Finally, we compiled our five categories using an additive indexation process to produce a spatially-explicit index of the wildfire-water risk (WWR). For comparison purposes, we aggregated index scores by global hydrological regions, or hydrobelts, for analysis. Overall, our results show a distinct pattern of medium-to-high risk levels in areas where sizeable wildfire activity, water resources, and water consumption are concomitant, which mainly encompasses temperate and sub-tropical zones. A closer look at hydrobelts reveals differences in the factors driving the risk, with fire activity being the primary factor of risk in the circumboreal forest, and freshwater resource density being prevalent in tropical areas. We also identified major urban areas across the world whose source waters should be protected from extreme fire events, particularly when

  2. A multimodal image sensor system for identifying water stress in grapevines

    Science.gov (United States)

    Zhao, Yong; Zhang, Qin; Li, Minzan; Shao, Yongni; Zhou, Jianfeng; Sun, Hong

    2012-11-01

    Water stress is one of the most common limitations of fruit growth. Water is the most limiting resource for crop growth. In grapevines, as well as in other fruit crops, fruit quality benefits from a certain level of water deficit which facilitates to balance vegetative and reproductive growth and the flow of carbohydrates to reproductive structures. A multi-modal sensor system was designed to measure the reflectance signature of grape plant surfaces and identify different water stress levels in this paper. The multi-modal sensor system was equipped with one 3CCD camera (three channels in R, G, and IR). The multi-modal sensor can capture and analyze grape canopy from its reflectance features, and identify the different water stress levels. This research aims at solving the aforementioned problems. The core technology of this multi-modal sensor system could further be used as a decision support system that combines multi-modal sensory data to improve plant stress detection and identify the causes of stress. The images were taken by multi-modal sensor which could output images in spectral bands of near-infrared, green and red channel. Based on the analysis of the acquired images, color features based on color space and reflectance features based on image process method were calculated. The results showed that these parameters had the potential as water stress indicators. More experiments and analysis are needed to validate the conclusion.

  3. Land Use, Climate, and Water Resources—Global Stages of Interaction

    Directory of Open Access Journals (Sweden)

    Sujay S. Kaushal

    2017-10-01

    Full Text Available Land use and climate change can accelerate the depletion of freshwater resources that support humans and ecosystem services on a global scale. Here, we briefly review studies from around the world, and highlight those in this special issue. We identify stages that characterize increasing interaction between land use and climate change. During the first stage, hydrologic modifications and the built environment amplify overland flow via processes associated with runoff-dominated ecosystems (e.g., soil compaction, impervious surface cover, drainage, and channelization. During the second stage, changes in water storage impact the capacity of ecosystems to buffer extremes in water quantity and quality (e.g., either losses in snowpack, wetlands, and groundwater recharge or gains in water and nutrient storage behind dams in reservoirs. During the third stage, extremes in water quantity and quality contribute to losses in ecosystem services and water security (e.g., clean drinking water, flood mitigation, and habitat availability. During the final stage, management and restoration strategies attempt to regain lost ecosystem structure, function, and services but need to adapt to climate change. By anticipating the increasing interaction between land use and climate change, intervention points can be identified, and management strategies can be adjusted to improve outcomes for realistic expectations. Overall, global water security cannot be adequately restored without considering an increasing interaction between land use and climate change across progressive stages and our ever-increasing human domination of the water cycle from degradation to ecosystem restoration.

  4. Land Use, Climate, and Water Resources-Global Stages of Interaction.

    Science.gov (United States)

    Kaushal, Sujay S; Gold, Arthur J; Mayer, Paul M

    2017-10-24

    Land use and climate change can accelerate the depletion of freshwater resources that support humans and ecosystem services on a global scale. Here, we briefly review studies from around the world, and highlight those in this special issue. We identify stages that characterize increasing interaction between land use and climate change. During the first stage, hydrologic modifications and the built environment amplify overland flow via processes associated with runoff-dominated ecosystems (e.g., soil compaction, impervious surface cover, drainage, and channelization). During the second stage, changes in water storage impact the capacity of ecosystems to buffer extremes in water quantity and quality (e.g., either losses in snowpack, wetlands, and groundwater recharge or gains in water and nutrient storage behind dams in reservoirs). During the third stage, extremes in water quantity and quality contribute to losses in ecosystem services and water security (e.g., clean drinking water, flood mitigation, and habitat availability). During the final stage, management and restoration strategies attempt to regain lost ecosystem structure, function, and services but need to adapt to climate change. By anticipating the increasing interaction between land use and climate change, intervention points can be identified, and management strategies can be adjusted to improve outcomes for realistic expectations. Overall, global water security cannot be adequately restored without considering an increasing interaction between land use and climate change across progressive stages and our ever-increasing human domination of the water cycle from degradation to ecosystem restoration.

  5. Effects of UV-B radiation and water stress on gas exchange of soybeans under two different nitrogen levels

    International Nuclear Information System (INIS)

    Rosa, L.M.; Forseth, I.N.

    1993-01-01

    Due to anthropogenic destruction of stratospheric ozone, UV-B radiation is projected to increase in the near future. Other potential global climate changes in temperature and precipitation patterns raise the need for research into plant responses to multiple environmental stresses. The objective of this study was to document UV-B and water stress effects on gas exchange of soybean (Glycine max Merr.) under two nitrogen levels. Two soybean cultivars differing in sensitivity to UV-B were tested at fluence rates of 19.1 or 8.5 kJ m -2 day -1 (enhance and natural levels of UV-B, respectively). Measurements of photosaturated CO 2 uptake at ambient CO 2 (A). stomatal conductance. photosaturated O 2 evolution at saturating CO 2 (A max ), long term water use efficiency (using δ 13 C), and nitrogen fixation (using 15 N) were performed. No significant treatment effects on A could be detected. However A max was significantly increased, and stomatal conductance reduced (p<0.01) by increased UV-B at all levels of water and nitrogen for both cultivars, suggesting a stronger stomal limitation of photosynthesis under UV-B. Water and nitrogen use efficiency also decreased under increased UV-B in both cultivars (p<0.01)

  6. Initiation of stress corrosion cracking in pre-stained austenitic stainless steels exposed to primary water

    International Nuclear Information System (INIS)

    Huguenin, P.

    2012-01-01

    Austenitic stainless steels are widely used in primary circuits of Pressurized Water Reactors (PWR) plants. However, a limited number of cases of Intergranular Stress Corrosion Cracking (IGSCC) has been detected in cold-worked (CW) areas of non-sensitized austenitic stainless steel components in French PWRs. A previous program launched in the early 2000's identified the required conditions for SCC of cold-worked stainless steels. It was found that a high strain hardening coupled with a cyclic loading favoured SCC. The present study aims at better understanding the role of pre-straining on crack initiation and at developing an engineering model for IGSCC initiation of 304L and 316L stainless steels in primary water. Such model will be based on SCC initiation tests on notched (not pre-cracked) specimens under 'trapezoidal' cyclic loading. The effects of pre-straining (tensile versus cold rolling), cold-work level and strain path on the SCC mechanisms are investigated. Experimental results demonstrate the dominating effect of strain path on SCC susceptibility for all pre-straining levels. Initiation can be understood as crack density and crack depth. A global criterion has been proposed to integrate both aspects of initiation. Maps of SCC initiation susceptibility have been proposed. A critical crack depth between 10 and 20 μm has been demonstrated to define transition between slow propagation and fast propagation for rolled materials. For tensile pre-straining, the critical crack depth is in the range 20 - 50 μm. Experimental evidences support the notion of a KISCC threshold, whose value depends on materials, pre-straining ant load applied. The initiation time has been found to depend on the applied loading as a function of (σ max max/YV) 11,5 . The effect of both strain path and surface hardening is indirectly taken into account via the yield stress. In this study, material differences rely on strain path effect on mechanical properties. As a result, a stress

  7. The Spanish Food Industry on Global Supply Chains and Its Impact on Water Resources

    Directory of Open Access Journals (Sweden)

    Rosa Duarte

    2014-12-01

    Full Text Available The study of the impact of economic activities on natural resources through global supply chains is increasingly demanded in the context of the growing globalization of economies and product fragmentation. Taking Spain as a case study and a sector with significant economic and environmental impacts, the agri-food industry, the objective of this work is two-fold. First, we estimate the associated water impact, both from the production and consumption perspectives, paying special attention to the water embodied in production exchanges among countries and sectors. To that aim, we use an environmentally-extended multiregional input-output model (MRIO. Second, we assess the main driving factors behind changes in direct and embodied water consumption between the years 1995 and 2009 by means of a structural decomposition analysis. The MRIO model provides a comprehensive estimate of the economic linkages among regions and economic sectors and, therefore, allows calculating the environmental impacts over international value chains. The results indicate that the food industry exerts large impacts on global water resources, particularly given the remarkable interactions with the domestic and foreign agricultural sectors, These growing linkages show how consumption patterns, and, therefore, lifestyles, involve large environmental impacts through the whole and global supply chains.

  8. Aerosol optical thickness retrieval over land and water using Global Ozone Monitoring Experiment (GOME) data

    NARCIS (Netherlands)

    Kusmierczyk-Michulec, J.; Leeuw, G. de

    2005-01-01

    An algorithm for the retrieval of the aerosol optical thickness over land and over water from Global Ozone Monitoring Experiment (GOME) data is presented. The cloud fraction in the GOME pixels is determined using the Fast Retrieval Scheme for Clouds From the Oxygen A Band (FRESCO) algorithm. Surface

  9. Sinking of Dense North Atlantic Waters in a Global Ocean Model : Location and Controls

    NARCIS (Netherlands)

    Katsman, C.A.; Drijfhout, SS; Dijkstra, H. A.; Spall, M. A.

    2018-01-01

    We investigate the characteristics of the sinking of dense waters in the North Atlantic Ocean that constitute the downwelling limb of the Atlantic Meridional Overturning Circulation (AMOC) as simulated by two global ocean models: an eddy-permitting model at 1/4° resolution and its coarser 1°

  10. Crop water stress maps for an entire growing season from visible and thermal UAV imagery

    DEFF Research Database (Denmark)

    Hoffmann, Helene; Jensen, Rasmus; Thomsen, Anton

    2016-01-01

    This study investigates whether a water deficit index (WDI) based on imagery from unmanned aerial vehicles (UAVs) can provide accurate crop water stress maps at different growth stages of barley and in differing weather situations. Data from both the early and late growing season are included...... to investigate whether the WDI has the unique potential to be applicable both when the land surface is partly composed of bare soil and when crops on the land surface are senescing. The WDI differs from the more commonly applied crop water stress index (CWSI) in that it uses both a spectral vegetation index (VI...... season because at this stage the remote sensing data represent crop water availability to a greater extent than they do in the early growing