276 research outputs found

    Groundwater investigation and modeling - western desert of Iraq

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    The region of interest is part from Iraqi western desert covering an area about 100,000 km². Several of the large wadis such as Hauran, Amij, Ghadaf, Tubal and Ubaiydh traverse the entire region and discharge into the Euphrates River. The present study included the following hydrogeological investigations: Lineaments interpretation was done by using different data sets (SRTM 30 m and Landsat ETM 15m), within different algorithms. Some faults recognized by field survey match rather well with the automatically extracted lineaments with only a small difference between field data and re-mote sensed data. The groundwater flow directions (west to east) for three aquifers were determined by using different spatial interpolation algorithms. Due to the faults impact, the flow direction gets a slightly other direction when reaching the fault’s zone. Two pumping test were performed close to fault 2 in the unconfined aquifer Dammam using well no. 9 and 17. Results of pumping test and recovery were evaluated with the analytical model MLU for Windows. Well 17 shows a slightly higher transmissivity (0.1048 m²/min) in compari-son to well 9 (T= 0.0832 m²/min). This supports the assumption of a zone of unique elevated permeability between fault 1 and fault 2 because of the tectonic stress and the anticline structure. The catchment and watershed delineation was performed by means of four GIS packages utilizing three DTM´s: 90 m and 30 m SRTM (Shuttle Radar Topography Mission) and the ASTER 30 m. A thorough field survey and manual catchment delineation of the same area was available from Division 1944. Software used was Arc Hydrotools, TNTmips, River Tools and TecDEM. Ten 90 m SRTM and twelve 30 m ASTER files were merged by means of ArcGIS. The 30 m SRTM dataset of Iraq was supplied by courtesy of the US Army and the region of interest (ROI) was clipped from this DTM using ArcGIS. No additional steps were performed with both DTM data sets before using the mentioned software products to perform the catchment analysis. As a result the catchment calculations were significantly different for both 30 m and 90 m data and the different software products. The groundwater model implemented in Visual Modflow V.4.2 was built by 5 main layers repre-senting Dammam aquifer, first aquiclude, UmEr Duhmma aquifer, second aquiclude and the Tayarat aquifer. Averaged readings of groundwater head from 102 observation wells were used to calibrate the model. Calculated recharge average was 17.5 mm/year based on the water balance for ~30 years (1980-2008). A sensitivity analysis was performed by using different permeability and recharge values. However, the model showed a rather low sensitivity because the values of the standard error of the estimation were between 2.27 m and 3.56 m. Models with recharge less than 11.85 mm/year or more than 60 mm/year did not converge and thus failed to produce a result. Models with Kf values from 1.1-3 to 1.1-4 m/s for aquifers and from 1.1-7 to 1.1-8 m/s for aquicludes converged. Water budget is about 2.17*10¹⁰ m³/year; by irrigating the greenhouses this budget will cover only 1.75% of the total area. However, this value could be upgraded up to 8 – 9 % by utilizing the groundwater inflow from Saudi Arabia.:List of Content Page Dedication ………………………………..………………..2 Acknowledgment ………………………………..………………..3 List of contents …………………………………..……………..4 List of Figures ………..……………………………..….......…8 List of Tables ………..……………………………….…….…9 List of abbreviations ………..……………………………….………10 English Abstract ……………………………………….………..12 German Abstract ..………………...…………………….……….14 1 Introduction ………..……………………………….………16 1-1 Preface ………..……………………………….………16 1-2 Region of interest ………..……………………………….………16 1-3 Previous Studies ………..……………………………….………17 1-3-1 Local studies ………..……………………………….………17 1-3-1-1 Hydrogeological Studies ………..………………………….…….17 1-3-1-2 Remote Sensing Studies ………..………………………….…….18 1-3-2 Global studies …..……………………………….…….18 1-3-2-1 Groundwater flow and fracture zone ..………………………...19 1-3-2-2 Lineaments extraction ………..…………………………….….19 1-3-2-3 Watershed delineation ………..……………………….……….20 1-4 Importance of investigation area ……………..………………..…24 1-5 Motivation ………..……………………………….…….…24 1-6 Deliverables ………..……………………………….………24 1-7 Problems ………..……………………………….………26 2 Methodology ………..……………………………….………27 2-1 Literature review ………..……………………………….………27 2-2 Personal contact ………..……………………………….………27 2-3 Field work ………..……………………………….………27 2-4 Evaluation of geological data ………………………….………27 2-4-1 Geological cross section ….……..……………………….27 2-4-2 Fault system by means of remote sensing techniques …..………28 2-5 Climate and Meteorology..…..………………………………....……28 2-5-1 Meteorological data ………..……………………………….………28 2-5-2 Aridity index ………..……………………………….………28 2-5-3 Groundwater recharge ………..…………………………….….29 2-5-4 Vegetation index ………..……………………………….………29 2-5-5 Actual evaporation ………..……………………………….………30 2-5-6 Soil moisture ………..……………………………….………32 2-5-7 Runoff ………..……………………………….………32 2-6 Hydrogeology ………..……………………………….………34 2-6-1 Pumping test ………..……………………………….………34 2-6-2 Groundwater flow ………..……………………………….………34 2-6-3 Wadi catchment delineation ……………………………….…34 2-6-3-1 Dataset ………..……………………………….………34 2-6-3-2 Approaches ………..……………………………….………34 2-6-3-3 Software packages ………..……………………………….………35 2-6-4 PC options ………..……………………………….………39 2-6-5 Groundwater Model ………..……………………………….………39 2-6-5-1 Conceptual model ………..……………………………….………40 2-6-5-2 Input ………..……………………………….………41 2-6-5-3 Properties ………..……………………………….………41 2-6-5-4 Boundary conditions ………..……………………………….………41 2-6-5-5 Observation wells ………..……………………………….………42 2-6-5-6 Solver ………..……………………………….………42 2-6-5-7 Calibration ………..……………………………….………42 3 Geological setting ………..……………………………….………44 3-1 Preface ………..……………………………….………44 3-2 Tectonic and structure …………………………………………..…...44 3-3 Stratigraphy ………..……………………………….………46 3-3-1 Tayarat formation ………..……………………………….………47 3-3-2 Umm Er Radhumma formation ………………………………....47 3-3-3 Dammam formation ………..……………………………….………48 3-3-4 Euphrates formation………..…………………………………………48 3-4 Topography and Ubaiydh Wadi …………………………………49 4 Climate and meteorology.…………………………………..………51 4-1 Preface ………..……………………………….………51 4-2 Precipitation ………..……………………………….………51 4-3 Temperature ………..……………………………….………52 4-4 Potential evaporation …………………………………………53 4-5 Relative humidity ………..……………………………….………54 4-6 Wind ………..……………………………….………55 4-7 Sunshine duration ………..……………………………….………56 5 Hydrogeology ………..……………………………….………57 5-1 Preface ………..……………………………….………57 5-2 Tayarat aquifer ………..……………………………….………57 5-2-1 Pressure conditions ………..……………………………….………57 5-2-2 Hydraulic characteristics …………………………………………57 5-2-3 Water quality ………..……………………………….………58 5-3 Um Er Radumma aquifer …………………………………………58 5-3-1 Pressure conditions ………..……………………………….………58 5-3-2 Hydraulic characteristics …………………………………………58 5-3-3 Water quality ………..……………………………….………59 5-4 Dammam aquifer ………..……………………………….………59 5-4-1 Pressure conditions ………..……………………………….………59 5-4-2 Hydraulic characteristics …………………………………………60 5-4-3 Water quality ………..……………………………….………60 6 Result and discussion …………………………………………61 6-1 Topographic contour map …………………………………………61 6-2 Geological cross section …………………………………………62 6-3 Lineaments evaluation …………………………………………65 6-4 Groundwater flow ………..……………………………….………66 6-5 Pumping test evaluation …………………………………………70 6-6 Catchment calculation …………………………………………72 6-7 Water balance and Recharge ……………………………….…76 6-8 Groundwater model ………..……………………………….………78 6.8.1 Model sensitivity ………..……………………………….………80 6.8.2 Groundwater management ……………………………….…83 7 Conclusion and recommendations …………………………………84 7.1 Conclusion ………..……………………………….…….…84 7.2 Recommendations ………..……………………………….…….…85 8 References ………..……………………………….………86 9 Appendixes ………..……………………………….………90 10 Field work Photos ………..……………………………….………115 11 Author CV. ………..……………………………….………116Das Untersuchungsgebiet umfasst eine Fläche von etwa 100.000 km² und ist Teil der westlichen irakischen Wüste. Einige der großen Wadis wie Hauran, Amij, Ghadaf, Tubal und Ubaiydh durchqueren die gesamte Region und entwässern in den Euphrat. Die vorliegende Arbeit umfasst folgende hydrogeologische Untersuchungen: Die Interpretation der Lineamente wurde anhand verschiedener Datensätze (SRTM 30 m und Landsat ETM 15 m) und unter Nutzung unterschiedlicher Algorithmen durchgeführt. Einige Störungen, welche während Feldmessungen identifiziert wurden, stimmen gut mit automatisch extrahierten Lineamenten überein, der Unterschied zwischen Feld- und Fernerkundungsdaten ist somit gering. Die Ermittlung der Grundwasserfließrichtungen (von West nach Ost) der drei Aquifere erfolgte unter Nutzung verschiedener Algorithmen zur räumlichen Interpolation. Es zeigte sich, dass die Störungen zu einer leichten Veränderung der Fließrichtung mit zunehmender Nähe zur Störungszone führen. Zwei Pumpversuche in den Brunnen 9 und 17 wurden nahe der Störung 2 im ungesättigten Aquifer Dammam durchgeführt. Die Auswertung der Ergebnisse der Pump- und Wiederanstiegsversuche erfolgte mittels des analytischen Modells MLU für Windows. Es zeigte sich, dass Brunnen 17 eine leicht höhere Transmissivität aufweist (T = 0,1048 m²/min) im Vergleich zu Brunnen 9 (T = 0,0832 m²/min). Dies unterstützt die Annahme der Existenz einer Zone erhöhter Permeabilität zwischen den Störungen 1 und 2, verursacht durch tektonischen Stress und die Antiklinalstruktur. Die Erfassung von Einzugsgebiet und Wasserscheiden erfolgte anhand von vier GIS-Paketen unter Nutzung von 3 DTM’s: 90 m und 30 m SRTM (Shuttle Radar Topography Mission) sowie ASTER 30 m. Genaue Daten aus einer Feldkampagne und eine manuelle Abgrenzung des Einzugsgebietes derselben Region standen zur Verfügung (Division 1944). Als Software kamen Arc Hydrotools, TNTmips, River Tools und TecDEM zum Einsatz. Zehn SRTM- (90 m) und zwölf ASTER-Files (30 m) wurden mittels ArcGIS vereinigt. Ein 30 m SRTM-Datensatz des Irak (bereitgestellt durch die US-Armee) diente als Grundlage für das Ausschneiden des Untersuchungsgebietes (ROI) mit Hilfe von ArcGIS. An beiden DTM Datensätzen wurden vor der Ermittlung des Einzugsgebietes mit den genannten Software-Produkten keine zusätzlichen Schritte durchgeführt. Als Resultat ergaben sich signifikante Unterschiede zwischen den 30 m und 90 m Datensätzen sowie der verschiedenen Software. Das in Visual Modflow V.4.2 implementierte Grundwassermodell wurde aus fünf Hauptschichten bestehend aus Dammam Aquifer, erster Stauer, UmEr Duhmma Aquifer, zweiter Stauer und Tayarat Aquifer aufgebaut. Durchschnittliche Werte der Grundwasserstände aus 102 Observationsbrunnen dienten der Kalibrierung des Modells. Die berechnete mittlere Grundwasserneubildung betrug 17,5 mm/a, basierend auf dem Wasserhaushalt der letzten 30 Jahre (1980-2008). Unter Einbeziehung verschiedener Werte für Permeabilität und Grundwasserneubildung wurde eine Sensitivitätsanalyse durchgeführt. Dabei ergab sich allerdings eine geringe Empfindlichkeit des Modells, resultierend aus einer Standardabweichung der Schätzung zwischen 2,27 m und 3,56 m. Modelle mit einer Grundwasserneubildung kleiner 11,85 mm/a und größer 60 mm/a zeigten keine Konvergenz und führten somit zu keinem Ergebnis. Modelle mit kf Werten zwischen 1.1-3 und 1.1-4 m/s für Aquifere und zwischen 1.1-7 und 1.1-8 m/s für Grundwasserstauer konvergierten. Die Grundwasserneubildung betrug etwa 2,17∙10¹⁰ m³/a, für die Bewässerung von Gewächshäusern deckt diese Summe nur 1,75% des gesamten Gebietes ab. Allerdings könnte dieser Wert durch die Nutzung des Grundwasserzuflusses aus Saudi Arabien auf 8 – 9% gesteigert werden.:List of Content Page Dedication ………………………………..………………..2 Acknowledgment ………………………………..………………..3 List of contents …………………………………..……………..4 List of Figures ………..……………………………..….......…8 List of Tables ………..……………………………….…….…9 List of abbreviations ………..……………………………….………10 English Abstract ……………………………………….………..12 German Abstract ..………………...…………………….……….14 1 Introduction ………..……………………………….………16 1-1 Preface ………..……………………………….………16 1-2 Region of interest ………..……………………………….………16 1-3 Previous Studies ………..……………………………….………17 1-3-1 Local studies ………..……………………………….………17 1-3-1-1 Hydrogeological Studies ………..………………………….…….17 1-3-1-2 Remote Sensing Studies ………..………………………….…….18 1-3-2 Global studies …..……………………………….…….18 1-3-2-1 Groundwater flow and fracture zone ..………………………...19 1-3-2-2 Lineaments extraction ………..…………………………….….19 1-3-2-3 Watershed delineation ………..……………………….……….20 1-4 Importance of investigation area ……………..………………..…24 1-5 Motivation ………..……………………………….…….…24 1-6 Deliverables ………..……………………………….………24 1-7 Problems ………..……………………………….………26 2 Methodology ………..……………………………….………27 2-1 Literature review ………..……………………………….………27 2-2 Personal contact ………..……………………………….………27 2-3 Field work ………..……………………………….………27 2-4 Evaluation of geological data ………………………….………27 2-4-1 Geological cross section ….……..……………………….27 2-4-2 Fault system by means of remote sensing techniques …..………28 2-5 Climate and Meteorology..…..………………………………....……28 2-5-1 Meteorological data ………..……………………………….………28 2-5-2 Aridity index ………..……………………………….………28 2-5-3 Groundwater recharge ………..…………………………….….29 2-5-4 Vegetation index ………..……………………………….………29 2-5-5 Actual evaporation ………..……………………………….………30 2-5-6 Soil moisture ………..……………………………….………32 2-5-7 Runoff ………..……………………………….………32 2-6 Hydrogeology ………..……………………………….………34 2-6-1 Pumping test ………..……………………………….………34 2-6-2 Groundwater flow ………..……………………………….………34 2-6-3 Wadi catchment delineation ……………………………….…34 2-6-3-1 Dataset ………..……………………………….………34 2-6-3-2 Approaches ………..……………………………….………34 2-6-3-3 Software packages ………..……………………………….………35 2-6-4 PC options ………..……………………………….………39 2-6-5 Groundwater Model ………..……………………………….………39 2-6-5-1 Conceptual model ………..……………………………….………40 2-6-5-2 Input ………..……………………………….………41 2-6-5-3 Properties ………..……………………………….………41 2-6-5-4 Boundary conditions ………..……………………………….………41 2-6-5-5 Observation wells ………..……………………………….………42 2-6-5-6 Solver ………..……………………………….………42 2-6-5-7 Calibration ………..……………………………….………42 3 Geological setting ………..……………………………….………44 3-1 Preface ………..……………………………….………44 3-2 Tectonic and structure …………………………………………..…...44 3-3 Stratigraphy ………..……………………………….………46 3-3-1 Tayarat formation ………..……………………………….………47 3-3-2 Umm Er Radhumma formation ………………………………....47 3-3-3 Dammam formation ………..……………………………….………48 3-3-4 Euphrates formation………..…………………………………………48 3-4 Topography and Ubaiydh Wadi …………………………………49 4 Climate and meteorology.…………………………………..………51 4-1 Preface ………..……………………………….………51 4-2 Precipitation ………..……………………………….………51 4-3 Temperature ………..……………………………….………52 4-4 Potential evaporation …………………………………………53 4-5 Relative humidity ………..……………………………….………54 4-6 Wind ………..……………………………….………55 4-7 Sunshine duration ………..……………………………….………56 5 Hydrogeology ………..……………………………….………57 5-1 Preface ………..……………………………….………57 5-2 Tayarat aquifer ………..……………………………….………57 5-2-1 Pressure conditions ………..……………………………….………57 5-2-2 Hydraulic characteristics …………………………………………57 5-2-3 Water quality ………..……………………………….………58 5-3 Um Er Radumma aquifer …………………………………………58 5-3-1 Pressure conditions ………..……………………………….………58 5-3-2 Hydraulic characteristics …………………………………………58 5-3-3 Water quality ………..……………………………….………59 5-4 Dammam aquifer ………..……………………………….………59 5-4-1 Pressure conditions ………..……………………………….………59 5-4-2 Hydraulic characteristics …………………………………………60 5-4-3 Water quality ………..……………………………….………60 6 Result and discussion …………………………………………61 6-1 Topographic contour map …………………………………………61 6-2 Geological cross section …………………………………………62 6-3 Lineaments evaluation …………………………………………65 6-4 Groundwater flow ………..……………………………….………66 6-5 Pumping test evaluation …………………………………………70 6-6 Catchment calculation …………………………………………72 6-7 Water balance and Recharge ……………………………….…76 6-8 Groundwater model ………..……………………………….………78 6.8.1 Model sensitivity ………..……………………………….………80 6.8.2 Groundwater management ……………………………….…83 7 Conclusion and recommendations …………………………………84 7.1 Conclusion ………..……………………………….…….…84 7.2 Recommendations ………..……………………………….…….…85 8 References ………..……………………………….………86 9 Appendixes ………..……………………………….………90 10 Field work Photos ………..……………………………….………115 11 Author CV. ………..……………………………….………11

    The effect of particle-associated viruses on disinfection processes in water treatment

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    This research focused on what accelerates or hinders virus-particle association, how the addition of turbidity affects both chlorine and ultraviolet light disinfection, and if sonication can disrupt virus-particle associations exposing viruses to disinfection methods. A decrease in pH, from 7--4, was found to accelerate association by 2-logs. Calcium increased association by 2.74-logs, and total organic carbon decreased association by 0.36-logs. An addition of 5 NTU, the maximum turbidity level allowed by USEPA for unfiltered drinking water supplies, affected both chlorine and UV light disinfection showing differences in the rate of kill per dose. The association of viruses and particles can hinder inactivation. These effects must be considered when disinfecting unfiltered drinking water sources because the rate of inactivation is reduced at higher turbidities

    Isolation and characterization of potato homologues of Arabidopsis thaliana genes operating in defense signal transduction

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    An increasing number of pathogen-defense related genes are being identified and characterized in Arabidopsis thaliana. So far, it is not known whether and which structural and functional homologues of these Arabidopsis genes have any role in natural variation of resistance to pathogens in crops. Using sequence database mining and PCR-based approaches, potato (Solanum tuberosum L.) gene fragments with high sequence similarity to 16 Arabidopsis defense signal transduction genes were obtained, sequenced and genetically positioned on potato molecular maps. Of 16 novel loci, five were positional candidates for known potato pathogen resistance QTL. One of the candidate loci, StAOS2 co-localizing with QTL for resistance to P. infestans and E. carotovora on linkage group XI, was further characterized in more detail. StAOS2 encodes a gene for allene oxide synthase, a cytochrome P450-enzyme, acting upstream in the jasmonic acid biosynthesis pathway. A metabolic block at the level of AOS completely abolishes JA production, which affects plant development (e.g. sterile pollen production) and various abiotic and biotic stress responses (e.g. P. infestans resistance in tomato, E. carotovora resistance in Arabidopsis). The chloroplastic localization of StAOS2-GFP was confirmed by confocal microscopy and functionality of the potato protein was proven by complementation of the male-sterile Arabidopsis aos mutant. StAOS2-RNAi transgenic lines in potato were generated in order to test role of StAOS2 in P. infestans resistance. The measurements of endogenous OPDA and JA in the silenced lines after wounding treatment revealed drastic decrease in the levels of above mentioned compounds (up to 25 folds less than in wild type plants). In addition, natural variation of StAOS2 locus was characterized. Sequencing of the locus across 38 potato chromosomes revealed high polymorphism. Thirteen distinct alleles were found, and four of them showed highly significant (P=0.000, R2=14%) linkage to P. infestans and E. carotovora QTL. Five alleles of StAOS2 were cloned. Sequence analyses revealed a substantial polymorphism on amino acid level, including non-conservative substitutions and an insertion/deletion within the cytochrome P450 domain. Currently, an ongoing quantitative complementation of the Ataos mutant with the five different StAOS2 alleles fused to the native AtAOS promoter, followed by OPDA and JA levels measurements in the transgenic lines, will possibly provide direct evidence for StAOS2 being the first plant resistance QTL identified

    Technical note: Introduction of a superconducting gravimeter as novel hydrological sensor for the Alpine research catchment Zugspitze

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    GFZ (German Research Centre for Geosciences) set up the Zugspitze Geodynamic Observatory Germany with a worldwide unique installation of a superconducting gravimeter at the summit of Mount Zugspitze on top of the Partnach spring catchment. This high alpine catchment is well instrumented, acts as natural lysimeter and has significant importance for water supply to its forelands, with a large mean annual precipitation of 2080ĝ€¯mm and a long seasonal snow cover period of 9 months, while showing a high sensitivity to climate change. However, regarding the majority of alpine regions worldwide, there is only limited knowledge on temporal water storage variations due to sparsely distributed hydrological and meteorological sensors and the large variability and complexity of signals in alpine terrain. This underlines the importance of well-equipped areas such as Mount Zugspitze serving as natural test laboratories for improved monitoring, understanding and prediction of alpine hydrological processes. The observatory superconducting gravimeter, OSG 052, supplements the existing sensor network as a novel hydrological sensor system for the direct observation of the integral gravity effect of total water storage variations in the alpine research catchment at Zugspitze. Besides the experimental set-up and the available data sets, the gravimetric methods and gravity residuals are presented based on the first 27 months of observations from 29 December 2018 to 31 March 2021. The snowpack is identified as being a primary contributor to seasonal water storage variations and, thus, to the gravity residuals with a signal range of up to 750ĝ€¯nms-2 corresponding to 1957ĝ€¯mm snow water equivalent measured with a snow scale at an altitude of 2420ĝ€¯m at the end of May 2019. Hydro-gravimetric sensitivity analysis reveal a snow-gravimetric footprint of up to 4ĝ€¯km distance around the gravimeter, with a dominant gravity contribution from the snowpack in the Partnach spring catchment. This shows that the hydro-gravimetric approach delivers representative integral insights into the water balance of this high alpine site. © Copyright

    A Survey on Routing Protocols for Large-Scale Wireless Sensor Networks

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    With the advances in micro-electronics, wireless sensor devices have been made much smaller and more integrated, and large-scale wireless sensor networks (WSNs) based the cooperation among the significant amount of nodes have become a hot topic. “Large-scale” means mainly large area or high density of a network. Accordingly the routing protocols must scale well to the network scope extension and node density increases. A sensor node is normally energy-limited and cannot be recharged, and thus its energy consumption has a quite significant effect on the scalability of the protocol. To the best of our knowledge, currently the mainstream methods to solve the energy problem in large-scale WSNs are the hierarchical routing protocols. In a hierarchical routing protocol, all the nodes are divided into several groups with different assignment levels. The nodes within the high level are responsible for data aggregation and management work, and the low level nodes for sensing their surroundings and collecting information. The hierarchical routing protocols are proved to be more energy-efficient than flat ones in which all the nodes play the same role, especially in terms of the data aggregation and the flooding of the control packets. With focus on the hierarchical structure, in this paper we provide an insight into routing protocols designed specifically for large-scale WSNs. According to the different objectives, the protocols are generally classified based on different criteria such as control overhead reduction, energy consumption mitigation and energy balance. In order to gain a comprehensive understanding of each protocol, we highlight their innovative ideas, describe the underlying principles in detail and analyze their advantages and disadvantages. Moreover a comparison of each routing protocol is conducted to demonstrate the differences between the protocols in terms of message complexity, memory requirements, localization, data aggregation, clustering manner and other metrics. Finally some open issues in routing protocol design in large-scale wireless sensor networks and conclusions are proposed

    Monetary Valuation of Waterfront Open Space in Coastal Areas of Mississippi and Alabama

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    Open space provides a wide range of ecosystem services to communities. In growing communities, open space offers relief from congestion and other negative externalities associated with rapid development. To make effective policy and planning decisions pertaining to open space preservation, it is important to estimate monetary values of its benefits. In addition, assessing public opinions regarding open space provides information on demand and how residents value open space. This study estimated the monetary value of open space in Mississippi and Alabama Gulf Coast communities. The study also collected information on coastal residents’ attitudes towards open space, working waterfronts, and their willingness to support waterfront open space preservation monetarily. Two methodological approaches were employed to estimate the monetary value of waterfront open space: contingent valuation (CVM) and hedonic price (HPM) methods. Data were collected using a mail survey, the Multiple Listing Service (MLS), and publicly available data sources such as the U.S. Census. Data were analyzed using an interval regression, ordinary least squares, and geographically weighted regression (GWR) models. Mail survey results indicated that the majority of residents valued open space and were willing to pay from 80.52to80.52 to 162.14 per household as estimated by four different interval-censored econometric models. Respondent’s membership in groups promoting conservation goals, income, age, and residence duration were major factors associated with their willingness to pay. Results from the HPM indicated proximities to waterfronts, with the exception of bayous, were positively related to home prices, suggesting open space produced positive economic benefits. Findings from the HPM analysis using publicly available data were consistent and comparable with the results from the HPM that used MLS data. This similarity of results indicates the use of publicly available data is feasible in HPM analysis, which is important for broad applications of the method during city planning. In addition, GWR estimates provided site specific monetary values of waterfront open space benefits, which will be helpful for policymakers and city planners in developing site-specific conservation and preservation strategies. Findings can help formulate future decisions related to alternative development scenarios of coastal areas and conservation efforts to preserve open space
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