Letteratura scientifica selezionata sul tema "Water quality measurement"

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Articoli di riviste sul tema "Water quality measurement"

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MACEKOVÁ, Ľudmila, e Matej ŽIGA. "THE WIRELESS SENSOR NETWORK CONCEPT FOR MEASUREMENT OF WATER QUALITY IN WATER STREAMS". Acta Electrotechnica et Informatica 14, n. 2 (1 giugno 2014): 60–67. http://dx.doi.org/10.15546/aeei-2014-0020.

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Muto, Giichi. "Some Ploblems on Water Quality Measurement". Japan journal of water pollution research 8, n. 11 (1985): 689. http://dx.doi.org/10.2965/jswe1978.8.689.

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Kwak, Pill Jae, Seog Ku Kim, Sang Leen Yun, Sung Won Kang, Hyun Dong Lee, Keun Ho Yang, Hee Jae Oh e Young Sung Kim. "Development of Multiple Water Quality Measurement Devices". Materials Science Forum 695 (luglio 2011): 606–9. http://dx.doi.org/10.4028/www.scientific.net/msf.695.606.

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The water quality measurement device that we developed measures pH, water temperature, conductivity, dissolved oxygen, turbidity and nitrate. And it measures all parameters simultaneously. The water resistant and screw packing technology also applied for improved mechanical reliability during water quality monitoring. A comparison between the performances of major company products (YSI, Hydrolab etc.) and this device don't provide a stark contrast. This device was verified through the KOREA’s Environmental Examination Methods. This device is offered reliable and cost-effective water quality monitoring solutions. Upgrades will be available and will include the technologies that are self-cleaning optical sensors with integrated wipers remove biofouling and maintain high data accuracy and optimal power management and built-in battery compartment extends in situ monitoring periods.
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Goda, Takeshi. "Monitoring and measurement of water quality parameters". International Journal of Water Resources Development 4, n. 4 (dicembre 1988): 270–75. http://dx.doi.org/10.1080/07900628808722401.

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., Priyanka N. Bande. "A SURVEY OF WATER QUALITY MEASUREMENT SENSORS". International Journal of Research in Engineering and Technology 05, n. 06 (25 giugno 2016): 161–65. http://dx.doi.org/10.15623/ijret.2016.0506031.

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IFUKU, Makoto, Teruya MASUMOTO, Hikaru SAEKI e Masato NAKATA. "CONTINUOUS MEASUREMENT OF WATER QUALITY WITH WATER-QUALITY PROFILING SYSTEM AT NOMURA RESERVOIR". Journal of Japan Society of Civil Engineers, Ser. B1 (Hydraulic Engineering) 67, n. 4 (2011): I_1567—I_1572. http://dx.doi.org/10.2208/jscejhe.67.i_1567.

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Chen, Chiung-Hsing, Yi-Chen Wu, Jia-Xiang Zhang e Ying-Hsiu Chen. "IoT-Based Fish Farm Water Quality Monitoring System". Sensors 22, n. 17 (5 settembre 2022): 6700. http://dx.doi.org/10.3390/s22176700.

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Typhoons in summer and cold snaps during winter in Taiwan often cause huge aquaculture losses. Simultaneously, the lack of human resources is a problem. Therefore, we used wireless transmission technology with various sensors to transmit the temperature, pH value, dissolved oxygen, water level, and life expectancy of the sensor in the fish farm to the server. The integrated data are transmitted to mobile devices through the Internet of Things, enabling administrators to monitor the water quality in a fish farm through mobile devices. Because the current pH sensors cannot be submerged in the liquid for a long time for measurements, human resources and time are required to take the instrument to each fish farm for testing at a fixed time. Therefore, a robotic arm was developed to complete automatic measurement and maintenance actions. We designed this arm with a programmable logic controller, a single chip combined with a wireless transmission module, and an embedded system. This system is divided into control, measurement, server, and mobility. The intelligent measurement equipment designed in this study can work 24 h per day, which effectively reduces the losses caused by personnel, material resources, and data errors.
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Oberoi, K., S. Purohit, P. A. Verma, A. Deshmukh, S. Saran e P. Chauhan. "GEOSPATIAL BASED CITIZEN CENTRIC WATER QUALITY MEASUREMENT SOLUTION". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-5 (19 novembre 2018): 75–78. http://dx.doi.org/10.5194/isprs-archives-xlii-5-75-2018.

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<p><strong>Abstract.</strong> Citizen science has emerged as a game changer in various scientific endeavors, wherein scientific data for understanding the phenomenon could be collected by volunteers/non-specialist in a quick possible time. Citizens nowadays play an important role by functioning as “sensors” helping government/institutions by collecting and analyzing data. The advancements and convergence of technologies (Information and communication technologies (ICT)), especially the Internet and mobile technology has further assisted in such efforts. Moreover, the location sensors (GPS) and camera on board the mobile devices enables citizens to collect geotagged data. The classic example is the OpenStreetMap project where volunteers contribute towards the mapping of the planet. This paper highlights the geospatial solution based on citizen science to collect geotagged data about the water quality (turbidity). This solution is developed using open source tools and consists of an Android based mobile app and web based dashboard on the server side for real time data visualization and analysis. The web application is designed and developed using PHP, JavaScript, HTML &amp; CSS and allows user to view the interpolated geotagged data about water quality over various background maps like OSM, Bhuvan etc. PostgreSQL/PostGIS are used as the backend geospatial data server for storing the geotagged dataset. Such solution will be very useful for water quality monitoring as part of national level project like Clean Ganga Mission using the citizen centric approach.</p>
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Fadhilah, M. F., Y. Hidayat e A. Hadiyane. "The role of the mahogany tree (Swietenia macrophylla King) on quantity and quality of water that fall below the canopy". IOP Conference Series: Earth and Environmental Science 918, n. 1 (1 novembre 2021): 012036. http://dx.doi.org/10.1088/1755-1315/918/1/012036.

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Abstract Mahogany trees (Swietenia macrophylla) are often planted in urban forests area. This shady-crowned tree has a role in controlling the quantity and quality of rainwater that falls to the ground. Mahogany trees also affect the quality of rainwater through interception, fall, and stemflow. The purpose of this research was to determine the impact of the interception process, such as throughfall and stemflow, on changes in rainwater quality of the mahogany tree. The Data that needed to be measured were tree dimension, rainfall interception, and rainwater quality. Interception measurement was performed by calculating the number of throughfall and stemflow in one month-measurement. While the measurement of rainwater quality was measured once in the laboratory. These water quality measurements include Electrical Conductivity (EC), hardness, the content of Elements Ca, Mg, Na and K, and pH concentrations. The results based on the total area of the crown showed that mahogany had an interception value of 18.088%. In the throughfall measurement, the mahogany has a throughfall of 81.799%, while the amount of the stemflow is only 0.113%. The correlation of interception values, throughfall, and stemflow with rainfall are in general positively correlated. That means the higher rainfall water will increase the number of interception, throughfall, and stemflow. The results on water quality measurement explain that Ec value in rainwater interception was increased compared to water produced from rainfall in mahogany trees. It also has the same condition in hardness measurement. In pH measurements, the interception of rainwater has less pH when compared to direct rainfall water. In addition, the content of Elements Ca, Mg, K, and Na in Stemflow and Throughfall water have more numbers than rainfall itself.
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Carriazo-Regino, Yulieth, Rubén Baena-Navarro, Francisco Torres-Hoyos, Juan Vergara-Villadiego e Sebastián Roa-Prada. "IoT-based drinking water quality measurement: systematic literature review". Indonesian Journal of Electrical Engineering and Computer Science 28, n. 1 (1 ottobre 2022): 405. http://dx.doi.org/10.11591/ijeecs.v28.i1.pp405-418.

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Sustainable development throughout the world depends on several factors such as the economy, quality education, agriculture, industry, among others, but the environment is one of the most important. Industrialization and new land use plans have caused the proliferation of pollutants in water resources, which poses a serious public challenge. As outlined in the sustainable development goals (SDGs), innovative water quality monitoring methods are needed to ensure access to water, sustainable management and sanitation. In this sense, technologies are sought that contribute to the development and implementation of groundwater and surface water quality monitoring systems in real time, so that their parameters can be evaluated through descriptive analysis, in rural populations and areas of difficult access. Nowadays, the internet of things (IoT) and the development of modern sensors are more used, so this research reviews the latest technologies to monitor and evaluate water quality using the potential and possibilities of the IoT. The main contribution of this article is to present an overview of the state of the art of IoT applications and instrumentation for water quality monitoring, focusing on the latest innovations, in order to identify interesting and challenging areas that can be explored in future research.
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Tesi sul tema "Water quality measurement"

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Bujatzeck, Baldur. "Statistical evaluation of water quality measurements". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0017/MQ44134.pdf.

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Jiang, Meng. "Evaluation of Low-Cost Water Quality Measurement System". Thesis, Mittuniversitetet, Avdelningen för elektronikkonstruktion, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-27179.

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Water is a very important element in our daily life, being able to check the water quality by ourselves would be a useful project to improve our life quality. My idea is to create something cheap and easy to examine the water quality and test it to see if it is capable for outdoor using as well. In this project I chose a DS18B20 as a temperature sensor. To get a system which can work as a water pump I chose an L298P as a motor driver board to support the electric motor, a Hall flow meter to get the flow and quantity, and a Water sensor to get the conductivity. With the Arduino and the Visual Studio user interface program, the system can extract the data that we want. The result of the measurement shows it is possible to analyse the water quality by comparing the conductivity of the known liquid to a test sample in a controlled environment. The system shows great promise of being a cheaper and easier system but still needs to improve accuracy, by reducing outside influence (like temperature), thereby enabling the system to work in more harsh environments.
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Rajele, Molefi Joseph. "A comparison of SAAS and chemical monitoring of the rivers of the Lesotho Highlands Water Project". Thesis, University of the Western Cape, 2004. http://etd.uwc.ac.za/index.php?module=etd&amp.

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The Lesotho Highlands Development Authority routinely uses the South African Scoring System version 4 (SASS4) in conjunction with water chemistry to monitor water quality of rivers in the Lesotho Highlands Water Project areas. The objective of this study was to test the efficiency of SASS4 in these areas.
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Saberi, Atefeh. "Automatic outlier detection in automated water quality measurement stations". Master's thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/25908.

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Des stations de mesure de la qualité de l’eau sont utilisées pour mesurer la qualité de l'eau à haute fréquence. Pour une gestion efficace de ces mesures, la qualité des données doit être vérifiée. Dans une méthode univariée précédemment développée, des points aberrants et des fautes étaient détectés dans les données mesurées par ces stations en employant des modèles à lissage exponentiel pour prédire les données au moment suivant avec l’intervalle de confiance. Dans la présente étude, ne considérant que le cas univarié, la détection de points aberrants est améliorée par l’identification d’un modèle autorégressif à moyenne mobile sur une fenêtre mobile de données pour prédire la donnée au moment suivant. Les données de turbidité mesurées à l'entrée d'une station d'épuration municipale au Danemark sont utilisées comme étude de cas pour comparer la performance de l’utilisation des deux modèles. Les résultats montrent que le nouveau modèle permet de prédire la donnée au moment suivant avec plus de précision. De plus, l’inclusion du nouveau modèle dans la méthode univariée présente une performance satisfaisante pour la détection de points aberrants et des fautes dans les données de l'étude de cas.
Water quality monitoring stations are used to measure water quality at high frequency. For effective data management, the quality of the data must be evaluated. In a previously developed univariate method both outliers and faults were detected in the data measured by these stations by using exponential smoothing models that give one-step ahead forecasts and their confidence intervals. In the present study, the outlier detection step of the univariate method is improved by identifying an auto-regressive moving average model for a moving window of data and forecasting one-step ahead. The turbidity data measured at the inlet of a municipal treatment plant in Denmark is used as case study to compare the performance of the use of the two models. The results show that the forecasts made by the new model are more accurate. Also, inclusion of the new forecasting model in the univariate method shows satisfactory performance for detecting outliers and faults in the case study data.
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Sharpe, Taylor Jeffery. "Assessing a Fluorescence Spectroscopy Method for In-Situ Microbial Drinking Water Quality". PDXScholar, 2017. https://pdxscholar.library.pdx.edu/open_access_etds/3838.

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Waterborne disease is a significant contributor to the global burden of disease, in particular among high-risk populations in developing nations. State-of-the-art methods for the enumeration of microbial pathogens in drinking water sources have important limitations, including high initial cost, 24-48 hour delays in results, high staffing and facility requirements, and training requirements which all become especially problematic in the developing nation context. A number of alternative approaches to microbial water quality testing have been proposed, with the goal of decreasing the required testing time, decreasing overall costs, leveraging appropriate technology approaches, or improving sensitivity or specificity of the water quality testing method. One approach that may offer solutions to some of these limitations involves the deployment of sensor networks using fluorescent spectroscopy to detect intrinsic protein fluorescence in water samples as a proxy for microbial activity. In recent years, a number of researchers have found significant and meaningful correlations between indicator bacteria species and the protein fluorescence of drinking water samples. Additionally, advances in the semiconductor industry could be used to drive down the cost of such sensors. This technology may also be extensible to other water quality parameters, including dissolved organic matter or the presence of fluorescent pollutants. In this thesis, a literature review describes the fundamentals of fluorescence spectroscopy, historical and recent work regarding the fluorescence of the amino acid tryptophan and associated bacterial fluorescence, possible mechanisms for this association, and potential applications of this technology for drinking water quality monitoring and waste water process control. Extensibility of the technology is also discussed. Next, experimental methodology in reproduction of similar results is described. Samples were taken from seven (7) surface water sources and tested using membrane filtration and an off-the-shelf fluorescence spectrometer to help examine the association between the presence of indicator bacteria and the tryptophan fluorescence of the water sample. The results, showing an association of R2 = 0.560, are compared to the results of recent similar experiments. Finally, two prototypes are described, including their design requirements and data from prototype testing. The results of the testing are briefly discussed, and next steps are outlined with the goal of developing a low-cost, in-situ microbial water quality sensor using fluorescence spectroscopy principles.
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Kwong, Pui-ki, e 鄺沛琪. "Surface water quality indicators in China and their implications for sustainability". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36618718.

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Nam, Kijin. "Optimization of paths and locations of water quality monitoring systems in surface water environments". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24745.

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Thesis (Ph.D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Aral, Mustafa; Committee Member: Guan, Jiabao; Committee Member: Kim, Seong-Hee; Committee Member: Roberts, Philip; Committee Member: Uzer, Turgay.
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岑永昌 e Wing-cheong Sham. "The determination of mercury in sediment, river water and seawater samples, and the determination of Cr(VI) in river water". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1991. http://hub.hku.hk/bib/B31210533.

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Peacock, Steven. "Storm Water System Monitoring for the Small Municipality Under Phase II of the National Pollutant Discharge Elimination System". Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc4298/.

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Storm water quality can have a significant impact on receiving water bodies. The chief recipients of these impacts are aquatic life in the receiving water body and downstream water users. Over the last few decades, legislation, regulations, institutions and facilities have evolved to recognize the impact of urban storm water on receiving streams. This increased emphasis has caused contaminants in storm water to be identified as a major concern. This developing concern has generated an increased interest in the water quality of our streams and lakes and emphasized the need for more monitoring efforts. With the passage of the National Pollutant Discharge Elimination System (NPDES) Phase II requirements, small municipalities are responsible for storm water impacts on receiving waters within their jurisdiction. For the purposes of NPDES Phase II requirements, small municipalities are identified as these municipalities that are typically composed of 10,000 but less than 100,000 in population. The purpose of this dissertation is to develop a manual for use by the staff of small municipalities in meeting the requirements prescribed by changes initiated in the NPDES Phase II regulations. Attempts were made to comply with these requirements within a very limited manpower and budget framework and to develop procedures that would allow for permit compliance using testing equipment that was both reliable and robust. The users' manual provides valuable guidance in the establishment of a knowledge base for characterization of the watersheds selected for study. Chapter 3 of the dissertation contains a users' manual, designed for use by municipal staff members in their efforts to comply with the NPDES Phase II requirements. Using the techniques and equipment capabilities developed during the writing of the users' manual a characterization of three watersheds within Denton County, Texas was developed. Non-storm water samples were taken from each of the streams and a baseline analysis was established. The three watersheds represented agricultural, suburban and urban settings. Storm water samples were obtained from multiple storms within all three watersheds and data analysis used to determine the character and impact of urban runoff. Determination of the constituents for analysis was based on monitoring requirements of the NPDES Phase I and II requirements for owners and operators of municipal separate storm sewer systems (MS4) and on the Texas Pollutant Discharge Elimination System (TPDES) Multi-Sector General Permit (MSGP). The three watersheds were determined to have multiple statistically significant differences for some parameters between their Base Flows and Storm Flows. The impact of urban runoff on the receiving waters of these three drainage systems was clearly demonstrated throughout the testing period.
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Slaughter, Andrew Robert. "Modelling the relationship between flow and water quality in South African rivers". Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1006196.

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The National Water Act (Act 36 of 1998) provides for an ecological Reserve as the quantity (flow) and quality of water needed to protect aquatic ecosystems. While there are methods available to quantify the ecological Reserve in terms of flow, methods of linking flow to water quality are lacking. Therefore, the research presented in this thesis investigated various modelling techniques to estimate the effect of flow on water quality. The aims of the research presented in this thesis were: Aim 1: Can the relationship between flow and water quality be accurately represented by simple statistical models? Aim 2: Can relatively simple models accurately represent the relationship between flow and water quality? Aim 3: Can the effect of diffuse sources be omitted from a water quality model and still obtain realistic simulations, and if so under what conditions? Aim 4: Can models that solely use historical monitoring data, accurately represent the relationships between flow and water quality? In Chapter 3, simple Q-C regressions of flow and water quality were investigated using Department of Water Affairs (DWA) historical monitoring data. It was found that while flow versus salinity regressions gave good regression fits in many cases, the Q-C regression approach is limited. A mechanistic/statistical model that attempted to estimate the point and diffuse signatures of nutrients in response to flow was developed in Chapter 4 using DWA historical monitoring data. The model was verified as accurate in certain case studies using observed point loading information. In Chapter 5, statistical models that link land cover information to diffuse nutrient signatures in response to flow using DWA historical data were developed. While the model estimations are uncertain due to a lack of data, they do provide an estimation of the diffuse signature within catchments where there is flow and land cover information available. Chapter 6 investigates the extension of an existing mass-balance salinity model to estimate the effect of saline irrigation return flow on in-stream salinity. The model gave accurate salinity estimates for a low order stream with little or no irrigation within its catchment, and for a permanently flowing river within a catchment used extensively for irrigation. Chapter 7 investigated a modelling method to estimate the reaction coefficients involved in nitrification using only DWA historical monitoring data. Here, the model used flow information to estimate the residence time of nutrients within the studied river reaches. While the model obtained good estimations of nitrification for the data it was applied to, very few DWA data sets were suitable for the model. Chapter 8 investigated the ability of the in-stream model QUAL2K to estimate nutrient concentrations downstream of point and diffuse inputs of nutrients. It was found that the QUAL2K model can give accurate results in cases where point sources dominate the total nutrient inputs into a river. However, the QUAL2K simulations are too uncertain in cases where there are large diffuse source inputs of nutrients as the load of the diffuse inputs is difficult to measure in the field. This research highlights the problem of data scarcity in terms of temporal resolution as well as the range of constituents measured within DWA historical monitoring data for water quality. This thesis in addition argues that the approach of applying a number of models is preferable to applying one model to investigate the research aims, as particular models would be suited to particular circumstances, and the development of new models allowed the research aims of this thesis to be explored more thoroughly. It is also argued that simpler models that simulate a few key processes that explain the variation in observed data, are more suitable for implementing Integrated Water Resource Management (IWRM) than large comprehensive water quality models. From this research, it is clear that simple statistical models are not adequate for modelling the relationship between flow and water quality, however, relatively simple mechanistic models that simulate a limited number of processes and water quality variables, can provide accurate representations of this relationship. Under conditions where diffuse sources are not a major factor within a catchment, models that omit diffuse sources can obtain realistic simulations of the relationship between flow and water quality. Most of the models investigated in this thesis demonstrate that accurate simulations of the relationships between flow and water quality can be obtained using solely historical monitoring data.
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Libri sul tema "Water quality measurement"

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Association, American Water Works, a cura di. Water quality. 4a ed. Denver, Colo: American Water Works Association, 2010.

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Ritter, Joseph A. Water quality. 4a ed. Denver, Colo: American Water Works Association, 2010.

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Bartram, Jamie. Water Quality Monitoring. London: Taylor & Francis Group Plc, 2003.

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Duerring, Christine L. Nantucket Harbor water quality survey: Water quality survey data, summary of significant findings, 1988. Westborough, Mass: Massachusetts Dept. of Environmental Protection, Division of Water Pollution Control, Technical Services Branch, 1990.

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Barbie, Dana L. Ground-water withdrawals, water levels, and ground-water quality in the Houston district, Texas, with emphasis on 1985-89. Austin, Tex: U.S Geological Survey, 1993.

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Barbie, Dana L. Ground-water withdrawals, water levels, and ground-water quality in the Houston district, Texas, with emphasis on 1985-89. Austin, Tex: U.S Geological Survey, 1993.

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Barbie, Dana L. Ground-water withdrawals, water levels, and ground-water quality in the Houston district, Texas, with emphasis on 1985-89. Austin, Tex: U.S Geological Survey, 1993.

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Barbie, Dana L. Ground-water withdrawals, water levels, and ground-water quality in the Houston district, Texas, with emphasis on 1985-89. Austin, Tex: U.S Geological Survey, 1993.

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Barbie, Dana L. Ground-water withdrawals, water levels, and ground-water quality in the Houston district, Texas, with emphasis on 1985-89. Austin, Tex: U.S Geological Survey, 1993.

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Barbie, Dana L. Ground-water withdrawals, water levels, and ground-water quality in the Houston district, Texas, with emphasis on 1985-89. Austin, Tex: U.S Geological Survey, 1993.

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Capitoli di libri sul tema "Water quality measurement"

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Boyd, Claude E., e Craig S. Tucker. "Measurement of Water Quality". In Pond Aquaculture Water Quality Management, 576–600. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5407-3_15.

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Perrier, E. R., e A. B. Salkini. "Water Quality, Irrigation Measurement and Efficiency". In Supplemental Irrigation in the Near East and North Africa, 177–89. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3766-9_12.

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Renger, E. "Measurement of Suspended Loads in Streams by Means of Hydrocyclones". In Estuarine Water Quality Management, 239–42. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-75413-5_36.

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Knutz, T., P. Koske e J. Rathlev. "Current Measurement in Estuaries by Electro-Magnetic Methods and DECCA-Drifters". In Estuarine Water Quality Management, 217–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-75413-5_31.

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Cerdà, V., J. Avivar, L. Ferrer e L. O. Leal. "Automatic Water and Wastewater Quality Monitoring Systems". In Smart Sensors, Measurement and Instrumentation, 105–23. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37006-9_5.

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Sam, Ajin Mathew, e C. Balaji. "Reconfigurable WSN Interface for Water Quality Measurement". In Advances in Intelligent Systems and Computing, 1279–85. New Delhi: Springer India, 2016. http://dx.doi.org/10.1007/978-81-322-2656-7_116.

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Li, D., e S. Liu. "Remote Monitoring of Water Quality for Intensive Fish Culture". In Smart Sensors, Measurement and Instrumentation, 217–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37006-9_10.

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Cleary, J., D. Maher e D. Diamond. "Development and Deployment of a Microfluidic Platform for Water Quality Monitoring". In Smart Sensors, Measurement and Instrumentation, 125–48. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37006-9_6.

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Cousin, Philippe, Anastasia Moumtzidou, Anastasios Karakostas, Lefteris Gounaridis, Christos Kouloumentas, Mauro Fernandes Pereira, Apostolos Apostolakis, Paula Gorrochategui, Guillaume Aoust e Bérengère Lebental. "Improving Water Quality and Security with Advanced Sensors and Indirect Water Sensing Methods". In Instrumentation and Measurement Technologies for Water Cycle Management, 251–77. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-08262-7_11.

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Honikel, K. O., e R. Hamm. "Measurement of water-holding capacity and juiciness". In Quality Attributes and their Measurement in Meat, Poultry and Fish Products, 125–61. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-2167-9_5.

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Atti di convegni sul tema "Water quality measurement"

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Peixeiro, R., O. Postolache e Jose Miguel Dias Pereira. "Virtual instrument for water quality parameters measurement". In 2012 International Conference and Exposition on Electrical and Power Engineering (EPE). IEEE, 2012. http://dx.doi.org/10.1109/icepe.2012.6463829.

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Yang, Ming. "Challenges for Water Quality Measurement for Produced Water Handling Subsea". In Offshore Technology Conference. Offshore Technology Conference, 2012. http://dx.doi.org/10.4043/23099-ms.

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Konyha, Jozsef. "Grid-based wide area water quality measurement system for surface water". In 2016 17th International Carpathian Control Conference (ICCC). IEEE, 2016. http://dx.doi.org/10.1109/carpathiancc.2016.7501120.

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Nayeem, Huzaifa, Azeemuddin Syed e Md Zafar Ali Khan. "Low Cost Wavelength Specific Water Quality Measurement Technique". In 2019 41st Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC). IEEE, 2019. http://dx.doi.org/10.1109/embc.2019.8857381.

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Mat Jafri, Mohammad Z., Khiruddin Abdullah, Mohammed N. Abu Bakar e Stephen Marshall. "Multispectral back-scattering spectrometer for water quality measurement". In AeroSense 2002, a cura di Xavier P. Maldague e Andres E. Rozlosnik. SPIE, 2002. http://dx.doi.org/10.1117/12.459571.

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fneer, M., J. Kurata, W. J. O. Boyle e K. T. V. Grattan. "Optical Fiber Ammonia Sensor For Water Quality Measurement". In Optical Fiber Sensors. Washington, D.C.: OSA, 1996. http://dx.doi.org/10.1364/ofs.1996.th35.

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Dias Pereira, J. M., O. Postolache e P. Silva Girao. "A Low-Cost Tide Measurement System for Water Quality Assessment". In IEEE Instrumentation and Measurement Technology Conference. IEEE, 2006. http://dx.doi.org/10.1109/imtc.2006.328567.

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J. M. Dias Pereira. "A Low-Cost Tide Measurement System for Water Quality Assessment". In 2006 IEEE Instrumentation and Measurement Technology. IEEE, 2006. http://dx.doi.org/10.1109/imtc.2006.234891.

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Zhao Xueliang, Shi Yun, Wang Xiaohui e Zhang Lei. "Embedded water quality field analyzer based on neural network". In 2009 International Conference on Test and Measurement (ICTM). IEEE, 2009. http://dx.doi.org/10.1109/ictm.2009.5413057.

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Muda, Nora, Norashikin Ramli e Zainol Mustafa. "Application of quality measurement tools in determining the quality of drinking water". In PROCEEDINGS OF THE 3RD INTERNATIONAL CONFERENCE ON MATHEMATICAL SCIENCES. AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4882594.

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Rapporti di organizzazioni sul tema "Water quality measurement"

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Pickering, Robert, Kathleen Onorevole, Rob Greenwood e Sarah Shadid. Measurement science roadmap workshop for water use efficiency and water quality in premise plumbing systems, August 1-2, 2018:. Gaithersburg, MD: National Institute of Standards and Technology, dicembre 2018. http://dx.doi.org/10.6028/nist.gcr.19-020.

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Starkey, Eric, Daniel McCay, Chrisopher Cooper e Mark Hynds. Assessment of estuarine water and sediment quality at Cape Hatteras National Seashore and Cape Lookout National Seashore: 2021 data summary. National Park Service, ottobre 2022. http://dx.doi.org/10.36967/2294854.

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In July 2021 the Southeast Coast Network conducted an assessment of water quality in the vicinity of Cape Hatteras and Cape Lookout National Seashores as part of the National Park Service Vital Signs Monitoring Program. Monitoring was conducted following methods developed by the Environmental Protection Agency (EPA) as part of the National Coastal Assessment Program (EPA 2010). Laboratory analysis measured chlorophyll a and total and dissolved concentrations of nitrogen and phosphorous. Field measurements included water temperature, pH, dissolved oxygen, and salinity. Water clarity, which requires a Secchi depth measurement, was obtained when possible. All measured parameters were rated as good, fair, or poor based on thresholds set by the EPA (2012). All measured parameters were rated as good, fair, or poor based on thresholds set by the EPA (2012). Water clarity was not calculated at all sites due to the shallow depth of the water in the sound. Of the sites where water clarity could be assessed (5 sites), four measured good and one fair. Sites that were too shallow to measure water clarity had water column conditions that did not preclude light from penetrating to the bottom of the water body so no ecological effects would be expected.Turbidity measurements ranged from 1.0 to 8.0 FNU (Formazin Nephelometric Units) and are good (i.e. < 25 NTU [Nephelometric Turbidity Units]) according to North Carolina Standards (NC Administrative Code 2019). Note that turbidity units of FNU and NTU are roughly equivalent. Chlorophyll a concentration was rated good at 29 sites (97%), and fair at one site (3%). Dissolved inorganic nitrogen (DIN) concentration was good at all 30 sites (100%). Dissolved inorganic phosphorus (DIP) concentration was good at all 30 sites (100%). Dissolved oxygen concentration (bottom) was rated good at all 30 sites (100%). A water-quality condition summary index was calculated for each site sampled at Cape Hatteras and Cape Lookout National Seashores based on the categorical assessments of chlorophyll a, DIN and DIP concentrations, dissolved oxygen, and water clarity. This summary index indicated good water-quality conditions at all thirty sites (100%). Based on the summary water-quality index rating, overall water-quality conditions at Cape Hatteras and Cape Lookout National Seashores during sampling in 2021 were good. For sediment, ecological condition was ranked as good at 30 sites (100%). As a result, no adverse impacts to benthic organisms due to sediment contamination are anticipated at any of the sampled sites. This ranking was assigned according to the 2010 Environmental Protection Agency, National Coastal Condition Assessment (NCCA) thresholds for sediment chemistry.
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Bradford, Joe, Itzhak Shainberg e Lloyd Norton. Effect of Soil Properties and Water Quality on Concentrated Flow Erosion (Rills, Ephermal Gullies and Pipes). United States Department of Agriculture, novembre 1996. http://dx.doi.org/10.32747/1996.7613040.bard.

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Concentrated flow erosion in rills, pipes, ephermal gullies, and gullies is a major contributor of downstream sedimentation. When rill or gullies form in a landscape, a 3- to 5-fold increase in soil loss commonly occurs. The balance between the erosive power of the flow and the erosion resistance of the bed material determines the rate of concentrated flow erosion. The resistance of the bed material to detachment depends primarily on the magnitude of the interparticle forces or cohesion holding the particles and aggregates together. The effect of soil properties on bed material resistance and concentrated flow erosion was evaluated both in the laboratory and field. Both rill erodibility and critical hydraulic shear were greater when measured in 9.0 m long rills under field conditions compared with laboratory mini-flumes. A greater hydraulic shear was required to initiate erosion in the field compared to the mini-flume because of the greater aggregate and clod size and stability. Once erosion was initiated, however, the rate of erosion as a function of hydraulic shear was greater under field conditions because of the greater potential for slaking upon wetting and the greater soil surface area exposed to hydraulic shear. Erosion tests under controlled laboratory conditions with the mini-flume allowed individual soil variables to be studied. Attempts to relate rill erosion to a group soil properties had limited success. When individual soil properties were isolated and studied separately or grouped separately, some trends were identified. For example, the effect of organic carbon on rill erodibility was high in kaolinitic soils, low in smectitic soils, and intermediate in the soils dominated by illite. Slow prewetting and aging increased the cohesion forces between soil particles and decreased rill erodibility. Quick prewetting increased aggregate slaking and increased erodibility. The magnitude of the effect of aging depended upon soil type. The effect of clay mineralogy was evaluated on sand/clay mixtures with montmorillonite (M), Illite (I), and kaolinite (K) clays. Montmorillonite/sand mixtures were much less erodible than either illite or kaolonite sand mixtures. Na-I and Na-K sand mixtures were more erodible than Ca-I and Ca-K due to increased strength from ionic bonding and suppression of repulsive charges by Ca. Na-M was less erodiblethan Ca-M due to increased surface resulting from the accessibility of internal surfaces due to Na saturation. Erodibility decreased when salt concentration was high enough to cause flocculation. This occurred between 0.001 mole L-1 and 0.01 mole L-1. Measuring rill erodibility in mini-flumes enables the measurement of cohesive forces between particles and enhances our ability to learn more about cohesive forces resisting soil detachment under concentrated water flow.
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Raymond, Kara, Laura Palacios e Evan Gwilliam. Status of climate and water resources at Big Bend National Park: Water year 2019. A cura di Tani Hubbard. National Park Service, settembre 2022. http://dx.doi.org/10.36967/2294267.

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Climate and hydrology are major drivers of ecosystem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate, groundwater, streamflow, and water quality is central to assessing the condition of park resources. This report combines data collected on climate, groundwater, and springs at Big Bend National Park (NP) to provide an integrated look at climate and water conditions during water year (WY) 2019 (October 2018–September 2019). However, this report does not address the Rio Grande or its tributaries. Annual precipitation was higher than normal (1981–2010) for Big Bend NP at four of the five National Oceanic and Atmospheric Administration Cooperative Observer Program weather stations: 111% of normal for Chisos Basin, 122% of normal for Panther Junction, 155% of normal for Persimmon Gap, and 124% of normal for Rio Grande Village. Castolon had 88% of normal annual precipitation. All five stations had higher than normal rainfall in October and December, while rainfall totals were substantially below normal at all stations in November, February, and March. Monthly precipitation totals for April through September were more variable from station to station. Mean monthly maximum air temperatures were below normal in the fall months, with Panther Junction as much as 7.5°F below normal in October. Monthly temperatures from January through July were more variable. Temperatures in August and September were warmer than normal at every station, up to +9.4°F at Rio Grande Village and +8.7°F at Chisos Basin in July. The reconnaissance drought index values indicate generally wetter conditions (based on precipitation and evaporative demand) at Chisos Basin since WY2016 and at Panther Junction and Persimmon Gap since WY2015, except for WY2017. This report presents the manual and automatic groundwater monitoring results at nine wells. Five wells had their highest water level in or just before WY2019: Panther Junction #10 peaked at 99.94 ft below ground surface (bgs) in September 2018, Contractor’s Well peaked at 31.43 ft bgs in November 2018, T-3 peaked at 65.39 ft bgs in December 2018, K-Bar #6 Observation Well peaked at 77.78 ft bgs in February 2019, and K-Bar #7 Observation Well peaked at 43.18 ft bgs in February 2019. This was likely in response to above normal rainfall in the later summer and fall 2018. The other monitoring wells did not directly track within-season precipitation. The last measurement at Gallery Well in WY2019 was 18.60 ft bgs. Gallery Well is located 120 feet from the river and closely tracked the Rio Grande stage, generally increasing in late summer or early fall following higher flow events. Water levels in Gambusia Well were consistently very shallow, though the manual well measurement collected in April was 4.25 ft bgs—relatively high for the monitoring record—and occurred outside the normal peak period of later summer and early fall. The last manual measurement taken at TH-10 in WY2019 was 34.80 ft bgs, only 0.45 ft higher than the earliest measurement in 1967, consistent with the lack of directional change in groundwater at this location, and apparently decoupled from within-season precipitation patterns. The last water level reading in WY2019 at Oak Springs #1 was 59.91 ft bgs, indicating an overall decrease of 26.08 ft since the well was dug in 1989. The Southwest Network Collaboration (SWNC) collects data on sentinel springs annually in the late winter and early spring following the network springs monitoring protocol. In WY2019, 18 sentinel site springs were visited at Big Bend NP (February 21, 2019–March 09, 2019). Most springs had relatively few indications of natural and anthropogenic disturbances. Natural disturbances included recent flooding, drying, and wildlife use. Anthropogenic disturbances included flow modifications (e.g., springboxes), hiking trails, and contemporary human use. Crews observed one to seven facultative/obligate wetland plant...
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Adam, Isabelle, Mihály Fazekas, Alfredo Hernandez Sanchez, Peter Horn e Nóra Regös. Integrity Dividends: Procurement in the Water and Sanitation Sector in Latin America and the Caribbean. A cura di Marcello Basani e Jacopo Gamba. Inter-American Development Bank, gennaio 2023. http://dx.doi.org/10.18235/0004688.

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Public procurement represents a large portion of government expenditure, more so in developing economies. Inefficiencies in public expenditures thus place a heavy burden on society. The Water and Sanitation (W&S) sector is especially vulnerable to public procurement inefficiencies due to the capital-intensive and complex nature of large-scale projects such as sewage, pipelines, and general maintenance. Recent studies have found that quality of corporate governance and transparency of water utilities as well as regulatory and supervisory agencies are key drivers of the sectors performance. To support better policies in the W&S sector, this report conducts a sectoral measurement of public procurement integrity using government administrative data and identifies effective interventions for improving the performance of utilities. The following questions are explored: Which types of integrity risk carry the highest economic costs? What are effective policy solutions? Which address the most impactful risks effectively? What are the price savings and project-delay-reducing impacts of such solutions? To this effect, the study analyzes data for six countries in the Latin American & Caribbean region. Several regression models were run to assess which indicators of integrity are good predictors of improved outcomes in terms of price (unit or relative) and quality (delays) of public purchases in the sector.
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Metcalfe, Chris, Lisa Guppy e Manzoor Qadir. Global Barriers To Improving Water Quality: A Critical Review. United Nations University Institute for Water, Environment and Health, gennaio 2017. http://dx.doi.org/10.53328/srlt7852.

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Sustainable Development Goal (SDG) 6 sets ambitious targets for improving global water quality prior to 2030. However, in low-income countries (LICs) and lower-middle-income countries (LMICs), there are significant barriers to improving water quality. Progress towards achieving the SGD 6 targets is unlikely unless there are programmes put in place to address these barriers. In this critical review, we document past experiences that show that interventions within LICs and LMICs to reduce sources of water pollution from industries, municipal wastewater and agricultural runoff have been largely ineffective. We review evidence that improvements to water quality are likely to lag behind advances in other SGD targets in countries with developing economies. Finally, water quality monitoring programmes in many nations are unlikely to be effective because of inadequate frequency and density of measurements, as well as unreasonable expectations regarding the scope of the monitoring programmes . We present some potential solutions to these problems, including setting realistic objectives for monitoring programmes, developing appropriate, lowcost solutions for pollution abatement and focusing on strengthening institutional and regulatory capacity.
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Castellano, Mike J., Abraham G. Shaviv, Raphael Linker e Matt Liebman. Improving nitrogen availability indicators by emphasizing correlations between gross nitrogen mineralization and the quality and quantity of labile soil organic matter fractions. United States Department of Agriculture, gennaio 2012. http://dx.doi.org/10.32747/2012.7597926.bard.

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A major goal in Israeli and U.S. agroecosystems is to maximize nitrogen availability to crops while minimizing nitrogen losses to air and water resources. This goal has presented a significant challenge to global agronomists and scientists because crops require large inputs of nitrogen (N) fertilizer to maximize yield, but N fertilizers are easily lost to surrounding ecosystems where they contribute to water pollution and greenhouse gas concentrations. Determination of the optimum N fertilizer input is complex because the amount of N produced from soil organic matter varies with time, space and management. Indicators of soil N availability may help to guide requirements for N fertilizer inputs and are increasingly viewed as indicators of soil health To address these challenges and improve N availability indicators, project 4550 “Improving nitrogen availability indicators by emphasizing correlations between gross nitrogen mineralization and the quality and quantity of labile organic matter fractions” addressed the following objectives: Link the quantity and quality of labile soil organic matter fractions to indicators of soil fertility and environmental quality including: i) laboratory potential net N mineralization ii) in situ gross N mineralization iii) in situ N accumulation on ion exchange resins iv) crop uptake of N from mineralized soil organic matter sources (non-fertilizer N), and v) soil nitrate pool size. Evaluate and compare the potential for hot water extractable organic matter (HWEOM) and particulate organic matter quantity and quality to characterize soil N dynamics in biophysically variable Israeli and U.S. agroecosystems that are managed with different N fertility sources. Ultimately, we sought to determine if nitrogen availability indicators are the same for i) gross vs. potential net N mineralization processes, ii) diverse agroecosystems (Israel vs. US) and, iii) management strategies (organic vs. inorganic N fertility sources). Nitrogen availability indicators significantly differed for gross vs. potential N mineralization processes. These results highlight that different mechanisms control each process. Although most research on N availability indicators focuses on potential net N mineralization, new research highlights that gross N mineralization may better reflect plant N availability. Results from this project identify the use of ion exchange resin (IERs) beads as a potential technical advance to improve N mineralization assays and predictors of N availability. The IERs mimic the rhizosphere by protecting mineralized N from loss and immobilization. As a result, the IERs may save time and money by providing a measurement of N mineralization that is more similar to the costly and time consuming measurement of gross N mineralization. In further search of more accurate and cost-effective predictors of N dynamics, Excitation- Emission Matrix (EEM) spectroscopy analysis of HWEOM solution has the potential to provide reliable indicators for changes in HWEOM over time. These results demonstrated that conventional methods of labile soil organic matter quantity (HWEOM) coupled with new analyses (EEM) may be used to obtain more detailed information about N dynamics. Across Israeli and US soils with organic and inorganic based N fertility sources, multiple linear regression models were developed to predict gross and potential N mineralization. The use of N availability indicators is increasing as they are incorporated into soil health assessments and agroecosystem models that guide N inputs. Results from this project suggest that some soil variables can universally predict these important ecosystem process across diverse soils, climate and agronomic management. BARD Report - Project4550 Page 2 of 249
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Warrick, Arthur, Uri Shani, Dani Or e Muluneh Yitayew. In situ Evaluation of Unsaturated Hydraulic Properties Using Subsurface Points. United States Department of Agriculture, ottobre 1999. http://dx.doi.org/10.32747/1999.7570566.bard.

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The primary information for accurately predicting water and solute movement and their impact on water quality is the characterization of soil hydraulic properties. This project was designed to develop methods for rapid and reliable estimates of unsaturated hydraulic properties of the soil. Particularly, in situ methodology is put forth, based on subsurface point sources. Devices were designed to allow introduction of water in subsurface settings at constant negative heads. The ability to operate at a negative head allows a direct method of finding unsaturated soil properties and a mechanism for eliminating extremely rapid preferential flow from the slow matrix flow. The project included field, laboratory and modeling components. By coupling the measurements and the modeling together, a wider range of designs can be examined, while at the same time realistic performance is assured. The developed methodology greatly expands the possibilities for evaluating hydraulic properties in place, especially for measurements in undisturbed soil within plant rooting zones. The objectives of the project were (i) To develop methods for obtaining rapid and reliable estimates of unsaturated hydraulic properties in situ, based on water distribution from subsurface point sources. These can be operated with a constant flow or at a constant head; (ii) To develop methods for distinguishing between matrix and preferential flow using cavities/permeameters under tension; (iii) To evaluate auxiliary measurements such as soil water content or tensions near the operating cavities to improve reliability of results; and (iv: To develop numerical and analytical models for obtaining soil hydraulic properties based on measurements from buried-cavity sources and the auxiliary measurements. The project began in July 1995 and was terminated in November 1998. All of the objectives were pursued. Three new subsurface point sources were designed and tested and two old types were also used. Two of the three new designs used a nylon cloth membrane (30 mm) arranged in a cylindrical geometry and operating at a negative water pressure (tension). A separate bladder arrangement allowed inflation under a positive pressure to maintain contact between the membrane and the soil cavity. The third new design used porous stainless steel (0.5 and 5 mm) arranged in six segments, each with its own water inlet, assembled to form a cylindrical supply surface when inflated in a borehole. The "old" types included an "off-the-shelf" porous cup as well as measurements from a subsurface drip emitter in a small subsurface cavity. Reasonable measurements were made with all systems. Sustained use of the cloth membrane devices were difficult because of leaks and plugging problems. All of the devices require careful consideration to assure contact with the soil system. Steady flow was established which simplified the analysis (except for the drip emitter which used a transient analysis).
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Minz, Dror, Stefan J. Green, Noa Sela, Yitzhak Hadar, Janet Jansson e Steven Lindow. Soil and rhizosphere microbiome response to treated waste water irrigation. United States Department of Agriculture, gennaio 2013. http://dx.doi.org/10.32747/2013.7598153.bard.

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Research objectives : Identify genetic potential and community structure of soil and rhizosphere microbial community structure as affected by treated wastewater (TWW) irrigation. This objective was achieved through the examination soil and rhizosphere microbial communities of plants irrigated with fresh water (FW) and TWW. Genomic DNA extracted from soil and rhizosphere samples (Minz laboratory) was processed for DNA-based shotgun metagenome sequencing (Green laboratory). High-throughput bioinformatics was performed to compare both taxonomic and functional gene (and pathway) differences between sample types (treatment and location). Identify metabolic pathways induced or repressed by TWW irrigation. To accomplish this objective, shotgun metatranscriptome (RNA-based) sequencing was performed. Expressed genes and pathways were compared to identify significantly differentially expressed features between rhizosphere communities of plants irrigated with FW and TWW. Identify microbial gene functions and pathways affected by TWW irrigation*. To accomplish this objective, we will perform a metaproteome comparison between rhizosphere communities of plants irrigated with FW and TWW and selected soil microbial activities. Integration and evaluation of microbial community function in relation to its structure and genetic potential, and to infer the in situ physiology and function of microbial communities in soil and rhizospere under FW and TWW irrigation regimes. This objective is ongoing due to the need for extensive bioinformatics analysis. As a result of the capabilities of the new PI, we have also been characterizing the transcriptome of the plant roots as affected by the TWW irrigation and comparing the function of the plants to that of the microbiome. *This original objective was not achieved in the course of this study due to technical issues, especially the need to replace the American PIs during the project. However, the fact we were able to analyze more than one plant system as a result of the abilities of the new American PI strengthened the power of the conclusions derived from studies for the 1ˢᵗ and 2ⁿᵈ objectives. Background: As the world population grows, more urban waste is discharged to the environment, and fresh water sources are being polluted. Developing and industrial countries are increasing the use of wastewater and treated wastewater (TWW) for agriculture practice, thus turning the waste product into a valuable resource. Wastewater supplies a year- round reliable source of nutrient-rich water. Despite continuing enhancements in TWW quality, TWW irrigation can still result in unexplained and undesirable effects on crops. In part, these undesirable effects may be attributed to, among other factors, to the effects of TWW on the plant microbiome. Previous studies, including our own, have presented the TWW effect on soil microbial activity and community composition. To the best of our knowledge, however, no comprehensive study yet has been conducted on the microbial population associated BARD Report - Project 4662 Page 2 of 16 BARD Report - Project 4662 Page 3 of 16 with plant roots irrigated with TWW – a critical information gap. In this work, we characterize the effect of TWW irrigation on root-associated microbial community structure and function by using the most innovative tools available in analyzing bacterial community- a combination of microbial marker gene amplicon sequencing, microbial shotunmetagenomics (DNA-based total community and gene content characterization), microbial metatranscriptomics (RNA-based total community and gene content characterization), and plant host transcriptome response. At the core of this research, a mesocosm experiment was conducted to study and characterize the effect of TWW irrigation on tomato and lettuce plants. A focus of this study was on the plant roots, their associated microbial communities, and on the functional activities of plant root-associated microbial communities. We have found that TWW irrigation changes both the soil and root microbial community composition, and that the shift in the plant root microbiome associated with different irrigation was as significant as the changes caused by the plant host or soil type. The change in microbial community structure was accompanied by changes in the microbial community-wide functional potential (i.e., gene content of the entire microbial community, as determined through shotgun metagenome sequencing). The relative abundance of many genes was significantly different in TWW irrigated root microbiome relative to FW-irrigated root microbial communities. For example, the relative abundance of genes encoding for transporters increased in TWW-irrigated roots increased relative to FW-irrigated roots. Similarly, the relative abundance of genes linked to potassium efflux, respiratory systems and nitrogen metabolism were elevated in TWW irrigated roots when compared to FW-irrigated roots. The increased relative abundance of denitrifying genes in TWW systems relative FW systems, suggests that TWW-irrigated roots are more anaerobic compare to FW irrigated root. These gene functional data are consistent with geochemical measurements made from these systems. Specifically, the TWW irrigated soils had higher pH, total organic compound (TOC), sodium, potassium and electric conductivity values in comparison to FW soils. Thus, the root microbiome genetic functional potential can be correlated with pH, TOC and EC values and these factors must take part in the shaping the root microbiome. The expressed functions, as found by the metatranscriptome analysis, revealed many genes that increase in TWW-irrigated plant root microbial population relative to those in the FW-irrigated plants. The most substantial (and significant) were sodium-proton antiporters and Na(+)-translocatingNADH-quinoneoxidoreductase (NQR). The latter protein uses the cell respiratory machinery to harness redox force and convert the energy for efflux of sodium. As the roots and their microbiomes are exposed to the same environmental conditions, it was previously hypothesized that understanding the soil and rhizospheremicrobiome response will shed light on natural processes in these niches. This study demonstrate how newly available tools can better define complex processes and their downstream consequences, such as irrigation with water from different qualities, and to identify primary cues sensed by the plant host irrigated with TWW. From an agricultural perspective, many common practices are complicated processes with many ‘moving parts’, and are hard to characterize and predict. Multiple edaphic and microbial factors are involved, and these can react to many environmental cues. These complex systems are in turn affected by plant growth and exudation, and associated features such as irrigation, fertilization and use of pesticides. However, the combination of shotgun metagenomics, microbial shotgun metatranscriptomics, plant transcriptomics, and physical measurement of soil characteristics provides a mechanism for integrating data from highly complex agricultural systems to eventually provide for plant physiological response prediction and monitoring. BARD Report
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Warrick, Arthur W., Gideon Oron, Mary M. Poulton, Rony Wallach e Alex Furman. Multi-Dimensional Infiltration and Distribution of Water of Different Qualities and Solutes Related Through Artificial Neural Networks. United States Department of Agriculture, gennaio 2009. http://dx.doi.org/10.32747/2009.7695865.bard.

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Abstract (sommario):
The project exploits the use of Artificial Neural Networks (ANN) to describe infiltration, water, and solute distribution in the soil during irrigation. It provides a method of simulating water and solute movement in the subsurface which, in principle, is different and has some advantages over the more common approach of numerical modeling of flow and transport equations. The five objectives were (i) Numerically develop a database for the prediction of water and solute distribution for irrigation; (ii) Develop predictive models using ANN; (iii) Develop an experimental (laboratory) database of water distribution with time; within a transparent flow cell by high resolution CCD video camera; (iv) Conduct field studies to provide basic data for developing and testing the ANN; and (v) Investigate the inclusion of water quality [salinity and organic matter (OM)] in an ANN model used for predicting infiltration and subsurface water distribution. A major accomplishment was the successful use of Moment Analysis (MA) to characterize “plumes of water” applied by various types of irrigation (including drip and gravity sources). The general idea is to describe the subsurface water patterns statistically in terms of only a few (often 3) parameters which can then be predicted by the ANN. It was shown that ellipses (in two dimensions) or ellipsoids (in three dimensions) can be depicted about the center of the plume. Any fraction of water added can be related to a ‘‘probability’’ curve relating the size of the ellipse (or ellipsoid) that contains that amount of water. The initial test of an ANN to predict the moments (and hence the water plume) was with numerically generated data for infiltration from surface and subsurface drip line and point sources in three contrasting soils. The underlying dataset consisted of 1,684,500 vectors (5 soils×5 discharge rates×3 initial conditions×1,123 nodes×20 print times) where each vector had eleven elements consisting of initial water content, hydraulic properties of the soil, flow rate, time and space coordinates. The output is an estimate of subsurface water distribution for essentially any soil property, initial condition or flow rate from a drip source. Following the formal development of the ANN, we have prepared a “user-friendly” version in a spreadsheet environment (in “Excel”). The input data are selected from appropriate values and the output is instantaneous resulting in a picture of the resulting water plume. The MA has also proven valuable, on its own merit, in the description of the flow in soil under laboratory conditions for both wettable and repellant soils. This includes non-Darcian flow examples and redistribution and well as infiltration. Field experiments were conducted in different agricultural fields and various water qualities in Israel. The obtained results will be the basis for the further ANN models development. Regions of high repellence were identified primarily under the canopy of various orchard crops, including citrus and persimmons. Also, increasing OM in the applied water lead to greater repellency. Major scientific implications are that the ANN offers an alternative to conventional flow and transport modeling and that MA is a powerful technique for describing the subsurface water distributions for normal (wettable) and repellant soil. Implications of the field measurements point to the special role of OM in affecting wettability, both from the irrigation water and from soil accumulation below canopies. Implications for agriculture are that a modified approach for drip system design should be adopted for open area crops and orchards, and taking into account the OM components both in the soil and in the applied waters.
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