Journal articles on the topic 'Site hydrology'
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Johnson, K. A., and N. Sitar. "Hydrologic conditions leading to debris-flow initiation." Canadian Geotechnical Journal 27, no. 6 (December 1, 1990): 789–801. http://dx.doi.org/10.1139/t90-092.
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Mitigation of the hazards posed by debris flows requires an understanding of the mechanisms leading to their initiation. The objectives of this study were to evaluate and document the hydrologic response of a potential debris-flow source area to major rainstorms and to evaluate whether traditional models of hillslope hydrology can account for the observed response. A field site in an area of previous debris-flow activity was instrumented and monitored for two winter seasons. Hydrologic responses for a wide variety of antecedent conditions were recorded, including two storm events that produced well-defined positive pore-pressure pulses at the site and initiated numerous debris flows in the immediate vicinity of the site. The observed hydrologic response was highly dependent on antecedent moisture conditions which can be characterized by soil matric suction measurements. The pressure-head pulses observed had a magnitude of approximately 50 cm of water, were transient, traveled downslope, and exhibited some spatial variability. Traditional models of hillslope hydrology do not fully account for the positive pore-pressure pulses observed high on the hillslope. Key words: debris flow, hillslope hydrology, pore pressure, antecedent moisture, tensiometer, piezometer, field investigation.
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Amatya, Devendra M., Thomas M. Williams, Jami E. Nettles, Richard W. Skaggs, and Carl C. Trettin. "Comparison of Hydrology of Two Atlantic Coastal Plain Forests." Transactions of the ASABE 62, no. 6 (2019): 1509–29. http://dx.doi.org/10.13031/trans.13387.
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Abstract. This article compares the short-term and long-term hydrology of two typical forests in the humid Atlantic Coastal Plain, including a relatively undisturbed forest with natural drainage in South Carolina (SC) and a drained pine plantation in North Carolina (NC), using monitoring and modeling approaches. Highly dynamic outflow (O) from both of these systems is driven by the water table (WT) position, as influenced by rainfall (R) and evapotranspiration (ET). The annual runoff coefficient (ROC) varied from 5% in dry years to 56% in wet years, depending on the soil water storage (SWS), with a significantly higher average value for the NC site despite its deeper WT, on average, than the SC site. Although both sites behaved similarly in extreme climate conditions, the change in SWS above the WT influenced the annual RO, ROC, and ET. The 17-year average annual ET of 1114 mm (R – O, assuming annual balanced SWS) for the SC site was significantly higher (p = 0.014) than the ET of the drained NC site (997 mm) despite the SC site’s lower mean annual R of 1370 mm, compared to 1520 mm for the NC site. This may be due to both the higher potential ET (PET) and soil water-holding capacity of the SC site. The SC site had higher frequency and duration of WT near the surface during winter, deeper summer WT, and higher correlation of annual ET to annual R (r2 = 0.90 vs. 0.15), suggesting that the SC site was often moisture-limited, particularly during the growing season. Most of the streamflow in these systems occurred during winter, with low ET demands. However, summer periods with tropical storms also resulted in large RO events, generally with higher frequency and longer durations at the drained NC site. These results are similar to an earlier short-term comparison with an unstable behavior period at the SC site after Hurricane Hugo (1989). This study highlighted (1) the differences in hydrology between coastal forests drained for silvicultural production and undrained natural forests managed only for restoration, (2) the importance of long-term monitoring and the effects of regeneration as well as vegetation management on flow regime, and (3) the application and limitations of two widely used models (MIKESHE and DRAINMOD) in describing the hydrology of these forests. Long-term studies can be a basis for testing new hypotheses on water yield, stormwater management, wetland hydrology, vegetation restoration, bioenergy production, and climate change, in addition to applications of proper models for assessing the eco-hydrologic impacts of land use and climate change on freshwater coastal forests linked with downstream riparian rivers and estuaries affected by tidal fluxes and sea level rise.HighlightsOutflow, driven by water table position on these forest systems, is highly variable, depending on its soil water storage.The hydrologic responses of both forest sites were similar during extreme climatic events or disturbances.Effect of forestry drainage on runoff was obscured by its large interannual differences.Long-term monitoring provides better insights on climate and vegetation management effects on flow regime and model validation Keywords: Drainage, Evapotranspiration, Hydrologic models, Pine forest, Poorly drained soils, Runoff coefficient, Water table.
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Shi, X., P. E. Thornton, D. M. Ricciuto, P. J. Hanson, J. Mao, S. D. Sebestyen, N. A. Griffiths, and G. Bisht. "Representing northern peatland microtopography and hydrology within the Community Land Model." Biogeosciences 12, no. 21 (November 12, 2015): 6463–77. http://dx.doi.org/10.5194/bg-12-6463-2015.
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Abstract. Predictive understanding of northern peatland hydrology is a necessary precursor to understanding the fate of massive carbon stores in these systems under the influence of present and future climate change. Current models have begun to address microtopographic controls on peatland hydrology, but none have included a prognostic calculation of peatland water table depth for a vegetated wetland, independent of prescribed regional water tables. We introduce here a new configuration of the Community Land Model (CLM) which includes a fully prognostic water table calculation for a vegetated peatland. Our structural and process changes to CLM focus on modifications needed to represent the hydrologic cycle of bogs environment with perched water tables, as well as distinct hydrologic dynamics and vegetation communities of the raised hummock and sunken hollow microtopography characteristic of peatland bogs. The modified model was parameterized and independently evaluated against observations from an ombrotrophic raised-dome bog in northern Minnesota (S1-Bog), the site for the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE). Simulated water table levels compared well with site-level observations. The new model predicts hydrologic changes in response to planned warming at the SPRUCE site. At present, standing water is commonly observed in bog hollows after large rainfall events during the growing season, but simulations suggest a sharp decrease in water table levels due to increased evapotranspiration under the most extreme warming level, nearly eliminating the occurrence of standing water in the growing season. Simulated soil energy balance was strongly influenced by reduced winter snowpack under warming simulations, with the warming influence on soil temperature partly offset by the loss of insulating snowpack in early and late winter. The new model provides improved predictive capacity for seasonal hydrological dynamics in northern peatlands, and provides a useful foundation for investigation of northern peatland carbon exchange.
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Shi, X., P. E. Thornton, D. M. Ricciuto, P. J. Hanson, J. Mao, S. D. Sebestyen, N. A. Griffiths, and G. Bisht. "Representing northern peatland microtopography and hydrology within the Community Land Model." Biogeosciences Discussions 12, no. 4 (February 20, 2015): 3381–418. http://dx.doi.org/10.5194/bgd-12-3381-2015.
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Abstract. Predictive understanding of northern peatland hydrology is a necessary precursor to understanding the fate of massive carbon stores in these systems under the influence of present and future climate change. Current models have begun to address microtopographic controls on peatland hydrology, but none have included a prognostic calculation of peatland water table depth for a vegetated wetland, independent of prescribed regional water tables. We introduce here a new configuration of the Community Land Model (CLM) which includes a fully prognostic water table calculation for a vegetated peatland. Our structural and process changes to CLM focus on modifications needed to represent the hydrologic cycle of bogs environment with perched water tables, as well as distinct hydrologic dynamics and vegetation communities of the raised hummock and sunken hollow microtopography characteristic of peatland bogs. The modified model was parameterized and independently evaluated against observations from an ombrotrophic raised-dome bog in northern Minnesota (S1-Bog), the site for the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE). Simulated water table levels compared well with site-level observations. The new model predicts significant hydrologic changes in response to planned warming at the SPRUCE site. At present, standing water is commonly observed in bog hollows after large rainfall events during the growing season, but simulations suggest a sharp decrease in water table levels due to increased evapotranspiration under the most extreme warming level, nearly eliminating the occurrence of standing water in the growing season. Simulated soil energy balance was strongly influenced by reduced winter snowpack under warming simulations, with the warming influence on soil temperature partly offset by the loss of insulating snowpack in early and late winter. The new model provides improved predictive capacity for seasonal hydrological dynamics in northern peatlands, and provides a useful foundation for investigation of northern peatland carbon exchange.
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Gardner, L. R., and H. W. Reeves. "Salt marsh hydrology data web site facilitates research." Eos, Transactions American Geophysical Union 84, no. 18 (2003): 168. http://dx.doi.org/10.1029/2003eo180007.
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Jan, Ahmad, Ethan T. Coon, and Scott L. Painter. "Evaluating integrated surface/subsurface permafrost thermal hydrology models in ATS (v0.88) against observations from a polygonal tundra site." Geoscientific Model Development 13, no. 5 (May 13, 2020): 2259–76. http://dx.doi.org/10.5194/gmd-13-2259-2020.
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Abstract. Numerical simulations are essential tools for understanding the complex hydrologic response of Arctic regions to a warming climate. However, strong coupling among thermal and hydrological processes on the surface and in the subsurface and the significant role that subtle variations in surface topography have in regulating flow direction and surface storage lead to significant uncertainties. Careful model evaluation against field observations is thus important to build confidence. We evaluate the integrated surface/subsurface permafrost thermal hydrology models in the Advanced Terrestrial Simulator (ATS) against field observations from polygonal tundra at the Barrow Environmental Observatory. ATS couples a multiphase, 3D representation of subsurface thermal hydrology with representations of overland nonisothermal flows, snow processes, and surface energy balance. We simulated thermal hydrology of a 3D ice-wedge polygon with geometry that is abstracted but broadly consistent with the surface microtopography at our study site. The simulations were forced by meteorological data and observed water table elevations in ice-wedge polygon troughs. With limited calibration of parameters appearing in the soil evaporation model, the 3-year simulations agreed reasonably well with snow depth, summer water table elevations in the polygon center, and high-frequency soil temperature measurements at several depths in the trough, rim, and center of the polygon. Upscaled evaporation is in good agreement with flux tower observations. The simulations were found to be sensitive to parameters in the bare soil evaporation model, snowpack, and the lateral saturated hydraulic conductivity. Timing of fall freeze-up was found to be sensitive to initial snow density, illustrating the importance of including snow aging effects. The study provides new support for an emerging class of integrated surface/subsurface permafrost simulators.
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Hare, Danielle K., David F. Boutt, William P. Clement, Christine E. Hatch, Glorianna Davenport, and Alex Hackman. "Hydrogeological controls on spatial patterns of groundwater discharge in peatlands." Hydrology and Earth System Sciences 21, no. 12 (November 30, 2017): 6031–48. http://dx.doi.org/10.5194/hess-21-6031-2017.
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Abstract. Peatland environments provide important ecosystem services including water and carbon storage, nutrient processing and retention, and wildlife habitat. However, these systems and the services they provide have been degraded through historical anthropogenic agricultural conversion and dewatering practices. Effective wetland restoration requires incorporating site hydrology and understanding groundwater discharge spatial patterns. Groundwater discharge maintains wetland ecosystems by providing relatively stable hydrologic conditions, nutrient inputs, and thermal buffering important for ecological structure and function; however, a comprehensive site-specific evaluation is rarely feasible for such resource-constrained projects. An improved process-based understanding of groundwater discharge in peatlands may help guide ecological restoration design without the need for invasive methodologies and detailed site-specific investigation. Here we examine a kettle-hole peatland in southeast Massachusetts historically modified for commercial cranberry farming. During the time of our investigation, a large process-based ecological restoration project was in the assessment and design phases. To gain insight into the drivers of site hydrology, we evaluated the spatial patterning of groundwater discharge and the subsurface structure of the peatland complex using heat-tracing methods and ground-penetrating radar. Our results illustrate that two groundwater discharge processes contribute to the peatland hydrologic system: diffuse lower-flux marginal matrix seepage and discrete higher-flux preferential-flow-path seepage. Both types of groundwater discharge develop through interactions with subsurface peatland basin structure, often where the basin slope is at a high angle to the regional groundwater gradient. These field observations indicate strong correlation between subsurface structures and surficial groundwater discharge. Understanding these general patterns may allow resource managers to more efficiently predict and locate groundwater seepage, confirm these using remote sensing technologies, and incorporate this information into restoration design for these critical ecosystems.
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Pyburn, K. Anne. "THE HYDROLOGY OF CHAU HIIX." Ancient Mesoamerica 14, no. 1 (January 2003): 123–29. http://dx.doi.org/10.1017/s0956536103141077.
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The Maya archaeological site of Chau Hiix, located slightly south and between the ancient cities of Lamanai and Altun Ha, is associated with some of the most extensive hydrological control features recorded from the pre-Hispanic era in the New World. The modest population size of the community, combined with this enormously productive agricultural technology, strongly implies economic interdependency among Classic-period sites. The location of Chau Hiix on an important inland water route further suggests the transportation of foodstuffs outside the local area.
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Snæbjörnsdóttir, Sandra Ó., Sigrún Tómasdóttir, Bergur Sigfússon, Edda Sif Aradóttir, Gunnar Gunnarsson, Auli Niemi, Farzad Basirat, et al. "The geology and hydrology of the CarbFix2 site, SW-Iceland." Energy Procedia 146 (July 2018): 146–57. http://dx.doi.org/10.1016/j.egypro.2018.07.019.
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Vourvopoulos, G., J. V. Brahana, E. Nolte, G. Korschinek, A. Priller, and B. Dockhorn. "36C1 measurements and the hydrology of an acid injection site." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 52, no. 3-4 (December 1990): 451–54. http://dx.doi.org/10.1016/0168-583x(90)90456-5.
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Klijn, Frans, and Jan-Philip M. Witte. "Eco-hydrology: Groundwater flow and site factors in plant ecology." Hydrogeology Journal 7, no. 1 (February 18, 1999): 65–77. http://dx.doi.org/10.1007/s100400050180.
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Peterman, Zell E., Leonid A. Neymark, K. J. King-Sharp, and Mel Gascoyne. "Isotope hydrology of the Chalk River Laboratories site, Ontario, Canada." Applied Geochemistry 66 (March 2016): 149–61. http://dx.doi.org/10.1016/j.apgeochem.2015.12.004.
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Aust, W. Michael, Mark D. Tippett, James A. Burger, and William H. McKee. "Compaction and Rutting During Harvesting Affect Better Drained Soils More Than Poorly Drained Soils on Wet Pine Flats." Southern Journal of Applied Forestry 19, no. 2 (May 1, 1995): 72–77. http://dx.doi.org/10.1093/sjaf/19.2.72.
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Abstract Soil compaction and rutting (puddling) are visually distinct types of wet-site harvesting disturbances; however, the way in which they affect soil physical properties and hydrology is not well documented. Three compacted and three rutted sites were evaluated to determine the effects of the disturbances on soil physical and hydrologic properties. For each site, primary skid trails and nontrafficked areas were compared. Both compaction and rutting increased bulk density, and reduced macropore space and saturated hydraulic conductivity. Water tables and reducing conditions were closer to the soil surface within the primary skid trails. For the compacted and rutted skid trails, changes were greatest on sites that initially had better drainage and aeration. Compacted sites may prove easier to mitigate with site preparation than rutted sites due to the shallower nature of the disturbances and drier site conditions that will facilitate mechanical mitigation. Submitted to South. J. Appl. For. 18(2):72-77.
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McCarthy, E. J., and R. W. Skaggs. "Simulation and Evaluation of Water Management Systems for a Pine Plantation Watershed." Southern Journal of Applied Forestry 16, no. 1 (February 1, 1992): 48–56. http://dx.doi.org/10.1093/sjaf/16.1.48.
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Abstract Water management on forest watersheds can have off-site impacts on the environment as well as on-site impacts on soil water conditions for plant growth. This study was conducted to evaluate the hydrologic impacts and soil water implications for plant growth of alternative water management practices. The forest watershed system modeled was a loblolly pine (Pinus taeda) plantation in the Coastal Plain of North Carolina. The site is characterized by flat, poorly drained soils (thermic typic umbraquults) which are drained with open ditches 100 m apart. No drainage, free (conventional) drainage, alternative forms of controlled drainage and stocking control were modeled to determine effects on water table position and drainage outflow. Silvicultural systems, including an unthinned and a commercially thinned regime, were modeled. The water management systems were evaluated by criteria quantifying both off-site implications and on-site plant-water relationships. Controlled drainage systems were found to be successful in reducing drainage outflow rates and volumes and improving soil water conditions for tree growth. In addition, hydrologic components were examined over the life of the unthinned and thinned forest stands, from planting to harvest. Stand development and silviculture were shown to have significant effects on the hydrology of the forest. South. J. Appl. For. 16(1):48-56.
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Elshafei, Y., M. Sivapalan, M. Tonts, and M. R. Hipsey. "A prototype framework for models of socio-hydrology: identification of key feedback loops with application to two Australian case-studies." Hydrology and Earth System Sciences Discussions 11, no. 1 (January 14, 2014): 629–89. http://dx.doi.org/10.5194/hessd-11-629-2014.
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Abstract. It is increasingly acknowledged that, in order to sustainably manage global freshwater resources, it is critical that we better understand the nature of human-hydrology interactions at the broader catchment system-scale. Yet to date, a generic conceptual framework for building models of catchment systems that include adequate representation of socioeconomic systems – and the dynamic feedbacks between human and natural systems – has remained elusive. In an attempt to work towards such a model, this paper outlines a generic framework for a model of socio-hydrology that posits a novel construct, a composite Community Sensitivity state variable, as a key link to elucidate the drivers of behavioural response in a hydrological context. The framework provides for both macro-scale contextual parameters, which allow it to be applied across climate, socioeconomic and political gradients, and catchment-specific conditions, by way of tailored "closure relationships", in order to ensure that site-specific and application-specific contexts of socio-hydrologic problems can be accommodated. To demonstrate how such a framework would be applied, two different socio-hydrological case studies, taken from the Australian experience, are presented and discussed. It is envisioned that the application of this framework across study sites and gradients will aid in developing our understanding of the fundamental interactions and feedbacks in such complex human-hydrology systems, and allow hydrologists to participate in the growing field of social-ecological systems modelling.
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Foster, Tammy E., and J. Renee Brooks. "Long-term trends in growth of Pinus palustris and Pinus elliottii along a hydrological gradient in central Florida." Canadian Journal of Forest Research 31, no. 10 (October 1, 2001): 1661–70. http://dx.doi.org/10.1139/x01-100.
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Forest species composition in Florida is sensitive to changes in hydrology that accompany small shifts in elevation. In this study, we use dendrochronological techniques to determine how the growth of Pinus elliottii var. elliottii Engelm. (slash pine) and Pinus palustris Mill. (longleaf pine) along a hydrologic gradient from mesic flatwoods to xeric sandhills responds to fluctuations in climate (temperature, precipitation, river flow, and Palmer drought severity index). Interspecies and intraspecies comparisons of growth responses were made between a xeric P. palustris plot, a transition zone plot containing both species, and a mesic P. elliottii plot. Growth of P. elliottii individuals was negatively correlated with increased water availability on sites with a shallow water table (<1 m) but positively correlated on sites with a deeper water table. The basal area increment (BAI) of P. elliottii individuals on the drier site was 41% lower than the BAI of individuals on the wetter site. In contrast, the growth response of P. palustris, which only grows in the dryer sites, was similar along the hydrologic gradient, with growth being positively related to water availability and only a 16% lower BAI on the driest site.
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Payne, Richard J., Richard J. Telford, Jeffrey J. Blackford, Antony Blundell, Robert K. Booth, Dan J. Charman, Łukasz Lamentowicz, et al. "Testing peatland testate amoeba transfer functions: Appropriate methods for clustered training-sets." Holocene 22, no. 7 (December 14, 2011): 819–25. http://dx.doi.org/10.1177/0959683611430412.
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Transfer functions are widely used in palaeoecology to infer past environmental conditions from fossil remains of many groups of organisms. In contrast to traditional training-set design with one observation per site, some training-sets, including those for peatland testate amoeba-hydrology transfer functions, have a clustered structure with many observations from each site. Here we show that this clustered design causes standard performance statistics to be overly optimistic. Model performance when applied to independent data sets is considerably weaker than suggested by statistical cross-validation. We discuss the reasons for these problems and describe leave-one-site-out cross-validation and the cluster bootstrap as appropriate methods for clustered training-sets. Using these methods we show that the performance of most testate amoeba-hydrology transfer functions is worse than previously assumed and reconstructions are more uncertain.
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Messaros, Roy C. "Application of the New Jersey Department of Environmental Protection Water Budget Manual to Finderne Farms Wetland Mitigation and Assessment of Project Performance." Journal of Ecosystems 2013 (October 1, 2013): 1–11. http://dx.doi.org/10.1155/2013/983438.
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The U.S. Army Corps of Engineers, NY District’s wetland mitigation proposal for Finderne Farms in Bridgewater, NJ, was approved in August 2005 by the state regulatory agency. The design goal was to provide mitigation for wetlands impacted by the Green Brook Flood Control project at a ratio of 2 : 1. As part of the design process in 2001, the available historical hydrologic data was evaluated. At that time, the NJ Department of Environmental Protection (NJDEP) Water Budget Manual was not available as a tool for accessing an acceptable design hydroperiod. Construction of the Finderne mitigation site was completed in July 2006. A six-year postconstruction monitoring program has determined that certain areas at the site have not achieved the established wetland success criteria. In 2012, there was a 28% survival of planted woody vegetation and a 74% cover of invasive species within Creation Area 1, a palustrine forested wetland. With the advent of the Water Budget Manual, a reevaluation of the historical hydrologic data was performed. Based on this analysis, the hydroperiod and soil moisture conditions are not representative of sustainable wetlands. Adaptive management measures are currently being developed and evaluated to improve the hydrology, hydric soil conditions, and survival of target vegetation at the Finderne site.
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Price, Jonathan S., Kern Ewing, Ming-ko Woo, and Kenneth A. Kershaw. "Vegetation patterns in James Bay coastal marshes. II. Effects of hydrology on salinity and vegetation." Canadian Journal of Botany 66, no. 12 (December 1, 1988): 2586–94. http://dx.doi.org/10.1139/b88-350.
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The vegetation of a coastal marsh in southern James Bay was examined in reference to the salinity and hydrological processes. Regional hydrologic influences related to the freshwater budget of James Bay reduce the local salinity so that the vegetation typifies that of a fresh to brackish marsh system, in contrast to the Hudson Bay salt marshes reported in the literature. Thus species that thrive in areas of higher salinity have only limited occurrence at the study site. Infrequent tidal inundation of low salinity bay water diminishes surface salinity, which is primarily controlled by the interaction of marsh hydrology with fossil salt diffusing upward from postglacial deposits. The soil water salinity increases with depth and distance inland. However, local hydrologic gradients near raised beach ridges and incised stream channels affect surface runoff and groundwater recharge and discharge, producing further distinct spatial variations in salinity. These processes thus control the distribution of saline water in the rooting zone and hence the patterns of vegetation.
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Sass-Klaassen, U., and E. Hanraets. "Woodlands of the past — The excavation of wetland woods at Zwolle-Stadshagen (the Netherlands): Growth pattern and population dynamics of oak and ash." Netherlands Journal of Geosciences - Geologie en Mijnbouw 85, no. 1 (March 2006): 61–71. http://dx.doi.org/10.1017/s0016774600021429.
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AbstractDendrochronology has been used to date sub-fossil wood excavated from former wetland woods located in Zwolle-Stadshagen, the Netherlands. Tree-ring analysis was performed on oak and ash to gain insight into changes in the growth dynamics of the trees resulting from changes in external site conditions, particularly hydrology. In addition population dynamics of oak and ash were studied by observing the temporal distribution and mean age of the oak and ash trees in the period when the woodland existed. The results showed that woodlands with oak and ash at Zwolle-Stadshagen existed at least for a period of about 700 years, from ca. 150 BC to AD 580 (ca. 2200 - 1400 cal. BP). The oak and ash were slowly growing and showed alternating phases of normal and depressed growth. Growth depressions occurred with a frequency of about 20 to 40 years. Almost all of these depressions were synchronous with those in oaks from other - mainly wetland areas - in NW Europe. Consequently, a regional (climate) factor must be considered responsible for this phenomenon. By taking into account the specific growth conditions in wetland woods it is very likely that this factor is linked to site hydrology. Around AD 300 (ca. 1650 cal. BP) a remarkable shift in population dynamics occurred in both oak and ash with many new trees establishing. This indicates a period of striking changes in site hydrology preceding the collapse of the woodland starting around AD 530 (ca. 1420 cal. BP).
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Paleologos, E. K., T. S. Sarris, and M. Tolika. "Integration of an analytic element model in a stochastic analysis of infiltration into a complex unconfined aquifer system." Journal of Hydroinformatics 7, no. 1 (January 1, 2005): 53–59. http://dx.doi.org/10.2166/hydro.2005.0006.
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A hydrologic model based on the Analytic Elements Method (AEM) has been developed for a phreatic aquifer in the General Separations Area (GSA), of the Savannah River Site (SRS), South Carolina, USA. The AEM is a semi-analytical method that relies on the superposition of individual closed-form solutions of elements representing the main hydrologic features of a site. Our study adopts techniques from the stochastic subsurface hydrology to assess the impact of precipitation (and consequently infiltration) variations on the flow field. The precipitation was considered as a random variable following a statistical model that was obtained from a record of the past 112 years. A measure of the variability of the hydraulic head field is obtained through Monte Carlo simulations and a discussion on the uncertainty in different regions of the model is provided. The ease of model development and the small processing power required by AEM models, make the method applicable not only to initial investigations for the identification of test parameters and boundary conditions but also as a tool that in a stochastic framework can provide initial estimations of uncertainty associated with certain model assumptions.
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Woo, Ming-ko, and Zhaojun Xia. "Effects of Hydrology on the Thermal Conditions of the Active Layer." Hydrology Research 27, no. 1-2 (February 1, 1996): 129–42. http://dx.doi.org/10.2166/nh.1996.0024.
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Ground thawing and soil warming are governed by ground heat flux, soil thermal properties and the ice content of the soil, all of which are directly or indirectly influenced by the soil moisture status. Ground temperature and moisture were measured at two Arctic sites: a wetland site of frequent saturation and an adjacent pebbly loam site which was much drier. Both thermal conductivity and heat capacity were strongly affected by the ice and water contents. At both sites, about half of the ground heat flux was consumed by latent heat for ground thawing and a large fraction of heat was also conducted from the seasonally thawed zone into the permafrost, leaving only a small amount of heat to warm the active layer. The wetland soil had a shallower maximum depth of thaw than the drier site and this was due to the large ice content in its active layer. Our results demonstrate the ground thaw response to the thermal properties of the soil and its ice content, both of which are influenced by the hydrological conditions of the active layer.
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Krogh, Sebastian A., and John W. Pomeroy. "Simulating site-scale permafrost hydrology: Sensitivity to modelling decisions and air temperature." Journal of Hydrology 602 (November 2021): 126771. http://dx.doi.org/10.1016/j.jhydrol.2021.126771.
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Meierbachtol, T., J. Harper, and N. Humphrey. "Basal Drainage System Response to Increasing Surface Melt on the Greenland Ice Sheet." Science 341, no. 6147 (August 15, 2013): 777–79. http://dx.doi.org/10.1126/science.1235905.
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Surface meltwater reaching the bed of the Greenland ice sheet imparts a fundamental control on basal motion. Sliding speed depends on ice/bed coupling, dictated by the configuration and pressure of the hydrologic drainage system. In situ observations in a four-site transect containing 23 boreholes drilled to Greenland’s bed reveal basal water pressures unfavorable to water-draining conduit development extending inland beneath deep ice. This finding is supported by numerical analysis based on realistic ice sheet geometry. Slow meltback of ice walls limits conduit growth, inhibiting their capacity to transport increased discharge. Key aspects of current conceptual models for Greenland basal hydrology, derived primarily from the study of mountain glaciers, appear to be limited to a portion of the ablation zone near the ice sheet margin.
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Morrison, J., C. A. Madramootoo, and M. Chikhaoui. "Modeling agricultural land drainage under spring snowmelt conditions with DRAINMOD." Canadian Journal of Civil Engineering 41, no. 4 (April 2014): 275–84. http://dx.doi.org/10.1139/cjce-2013-0416.
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There are few computer models that can simulate winter freeze–thaw conditions and spring snowmelt hydrology for agricultural tile drained lands. DRAINMOD, which is used widely to simulate tile drainage flows, has not been extensively applied during colder periods in eastern Canada. This study analyzes the performance of DRAINMOD for surface runoff and subsurface drainage predictions in southern Quebec during spring snowmelt. The model was tested with five years of field data. DRAINMOD was found to be adequate in predicting spring snowmelt hydrology, except for subsurface drainage at one site. It was found that soil characteristics had a major influence on model performance.
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Gazoty, A., G. Fiandaca, J. Pedersen, E. Auken, A. V. Christiansen, and J. K. Pedersen. "Application of time domain induced polarization to the mapping of lithotypes in a landfill site." Hydrology and Earth System Sciences 16, no. 6 (June 29, 2012): 1793–804. http://dx.doi.org/10.5194/hess-16-1793-2012.
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Abstract. A direct current (DC) resistivity and time domain induced polarization (TDIP) survey was undertaken at a decommissioned landfill site situated in Hørløkke, Denmark, for the purpose of mapping the waste deposits and to discriminate important geological units that control the hydrology of the surrounding area. It is known that both waste deposits and clay have clear signatures in TDIP data, making it possible to enhance the resolution of geological structures compared to DC surveys alone. Four DC/TDIP profiles were carried out crossing the landfill, and another seven profiles in the surroundings provide a sufficiently dense coverage of the entire area. The whole dataset was inverted using a 1-D laterally constrained inversion scheme, recently implemented for TDIP data, in order to use the entire decay curves for reconstructing the electrical parameters of the soil in terms of the Cole-Cole polarization model. Results show that it is possible to resolve both the geometry of the buried waste body and key geological structures. In particular, it was possible to find a silt/clay lens at depth that correlates with the flow direction of the pollution plume spreading out from the landfill and to map a shallow sandy layer rich in clay that likely has a strong influence on the hydrology of the site. This interpretation of the geophysical findings was constrained by borehole data, in terms of geology and gamma ray logging. The results of this study are important for the impact of the resolved geological units on the hydrology of the area, making it possible to construct more realistic scenarios of the variation of the pollution plume as a function of the climate change.
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Gazoty, A., G. Fiandaca, J. Pedersen, E. Auken, A. V. Christiansen, and J. K. Pedersen. "Application of time domain induced polarization to the mapping of lithotypes in a landfill site." Hydrology and Earth System Sciences Discussions 9, no. 1 (January 18, 2012): 983–1011. http://dx.doi.org/10.5194/hessd-9-983-2012.
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Abstract. A DC resistivity (DC) and Time Domain Induced Polarization (TDIP) survey was undertaken at a decommissioned landfill site situated in Hørløkke, Denmark, for the purpose of mapping the waste deposits and to discriminate important geological units that control the hydrology of the surrounding area. It is known that both waste deposits and clay have clear signatures in TDIP data, making possible to enhance the resolution of geological structures, when compared to DC surveys alone. Four DC/TDIP profiles were carried out crossing the landfill and another seven profiles in the surroundings, giving a dense coverage over the entire area. The whole dataset was inverted using a 1-D Laterally Constrained Inversion scheme, recently implemented for IP data, in order to use the entire decay curves for reconstructing the electrical parameters of the soil in terms of the Cole-Cole polarization model. Results show that it is possible to both resolve the geometry of the buried waste body and key geological structures. In particular, it was possible to find a silt/clay lens at depth, which correlates with the flow direction of the pollution plume spreading out from the landfill, and to map a shallow sandy layer rich in clay that likely has a strong influence on the hydrology of the site. This interpretation of the geophysical findings was constrained by boreholes data, in terms of geology and gamma ray logging. The results of this study are important for the impact that the resolved geological units have in the hydrology of the area, making it possible to construct more realistic scenarios of the variation of the pollution plume as a function of the climate change.
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Burn, Donald H., and William J. DeWit. "Spatial characterization of drought events using synthetic hydrology." Canadian Journal of Civil Engineering 23, no. 6 (December 1, 1996): 1231–40. http://dx.doi.org/10.1139/l96-932.
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This paper describes an approach to spatial drought analysis based on multi-site streamflow synthesis. The approach developed can be used to assist with the quantification of the return period for the drought of record and can also be used to facilitate the identification of daesign drought events of a specified return period. The approach was applied to the Nelson–Churchill River basin in Manitoba, Canada. For this system, the impacts of droughts on power generation were investigated in addition to a determination of the return period for the drought of record. Key words: droughts, streamflow generation, frequency analysis, hydroelectric power.
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Schroeder, Daniel W., Seneshaw Tsegaye, Thomas L. Singleton, and Kevin K. Albrecht. "GIS- and ICPR-Based Approach to Sustainable Urban Drainage Practices: Case Study of a Development Site in Florida." Water 14, no. 10 (May 12, 2022): 1557. http://dx.doi.org/10.3390/w14101557.
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Stormwater control is an urgent concern in cities where the increased impervious surface has disrupted natural hydrology, particularly causing a reduction in groundwater recharge which is the source of potable water supply for many communities. Water managers are increasingly turning towards infiltration-based stormwater management options (ISMOs) to help minimize flooding and mitigate the impact of urbanization on the local hydrologic systems. This paper offers a unique hydrologic and hydraulic (H&H) modeling approach using the Geographic Information System (GIS) and Interconnected Pond and Channel Routing (ICPR) software to help quantify the associated flood stage and groundwater recharge benefits of using ISMOs. The proposed approach incorporated ICPR percolation links and utilization of the curve number and Green-Ampt infiltration methods into the case study design, as well as an analysis of the effectiveness of including low-impact development practices. This analysis shows a 13–36% reduction in stormwater volume leaving the proposed site when percolation links were utilized to account for percolation from the proposed ISMOs. These reduction provides an indirect estimate of groundwater recharge benefits. The conversion from impervious parking to a pervious one and inclusion of rainwater harvesting from the roof area resulted in a further reduction in peak stages ranging from 1.20 to 7.62 cm.
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Shaohong, Pan, and Zhang Hongpin. "Comparative study on dam site selection in the pre-feasibility stage of Shitouzhai Hydropower Station." E3S Web of Conferences 233 (2021): 03044. http://dx.doi.org/10.1051/e3sconf/202123303044.
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The selection of dam site is the key content in the early stage of hydropower station project. Based on the hydrology, topographic and geological conditions, kinetic energy economic indexes, flood loss of reservoir, project layout, electromechanical and metal structure, construction conditions and project investment of the proposed dam site, this paper makes an in-depth analysis of the dam site selection in the pre-feasibility stage of Shitouzhai Hydropower Station, in order to provide beneficial inspiration for the design of similar projects.
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Freebairn, D. M., G. H. Wockner, N. A. Hamilton, and P. Rowland. "Impact of soil conditions on hydrology and water quality for a brown clay in the north-eastern cereal zone of Australia." Soil Research 47, no. 4 (2009): 389. http://dx.doi.org/10.1071/sr07054.
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Hydrology and water quality impacts of alternative land management practices are poorly quantified for semi-arid environments in the northern Australia cropping zone, yet wide-scale changes in tillage practices and land use were being recommended based on experience from other environments. The objective of this study was to explore changes in soil profile and catchment hydrology and water quality associated with different soil surface conditions created by different tillage and grazing practices. Soil water, runoff, and suspended sediment concentrations were monitored on 4 contour bay catchments over an 18-year period. Soil conditions were described by soil moisture, soil cover, and surface roughness in order to explore functional relationships between management, hydrology, and water quality. The site was chosen to represent the drier margins of cropping in southern Queensland where clay soils with high water-holding capacity, in conjunction with fallowing to store water for later crop growth, are an essential risk management tool. Accumulation of soil water in fallows was inefficient, with fallow efficiencies ranging from –7 to 40% due to high evaporation and runoff losses. Runoff amount was determined by soil water content, which was strongly influenced by antecedent rainfall, water use, and evaporation patterns. Surface cover and roughness had subtle influences on runoff, and a greater effect on suspended sediment concentration. Runoff and suspended sediment losses were considerably lower under pasture than cropping. A participative approach between farmers and scientists was demonstrated to be an efficient method to carry out an extensive and long-term catchment study at a remote location. This study provides benchmark data for future hydrologic and water quality investigations.
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Shojaeizadeh, Geza, McCray, and Hogue. "Site-Scale Integrated Decision Support Tool (i-DSTss) for Stormwater Management." Water 11, no. 10 (September 28, 2019): 2022. http://dx.doi.org/10.3390/w11102022.
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A site-scale integrated decision support tool (i-DSTss) is developed for selection and sizing of stormwater Best Management Practices (BMPs). The tool has several component modules—hydrology, BMP selection, BMP sizing, and life-cycle cost analysis (LCCA)—integrated into a single platform. The hydrology module predicts runoff from small catchment on event and continuous basis using the Green-Ampt and Curve Number methods. The module predicted runoff from a small residential area and a parking lot with R2 value of 0.77 and 0.74, respectively. The BMP selection module recommends a BMP type appropriate for a site based on economic, technical, social and environmental criteria using a multi-criteria optimization approach. The BMP sizing module includes sizing options for green roofs, infiltration-based BMPs, and storage-based BMPs. A mass balance approach is implemented for all types of BMPs. The tool predicted outflow rates from a permeable pavement with R2 value of 0.89. A cost module is included where capital, operation and maintenance, and rehabilitation costs are estimated based on BMP size obtained from the sizing module. The i-DSTss is built on an accessible platform (Microsoft Excel VBA) and can be operated with a basic skillset. The i-DSTss is intended for designers, regulators, and municipalities for quick analysis of scenarios involving interaction among several factors.
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Malcolm, I. A., D. M. Hannah, M. J. Donaghy, C. Soulsby, and A. F. Youngson. "The influence of riparian woodland on the spatial and temporal variability of stream water temperatures in an upland salmon stream." Hydrology and Earth System Sciences 8, no. 3 (June 30, 2004): 449–59. http://dx.doi.org/10.5194/hess-8-449-2004.
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Abstract. The spatio-temporal variability of stream water temperatures was investigated at six locations on the Girnock Burn (30km2 catchment), Cairngorms, Scotland over three hydrological years between 1998 and 2002. The key site-specific factors affecting the hydrology and climatology of the sampling points were investigated as a basis for physical process inference. Particular emphasis was placed on assessing the effects of riparian forest in the lower catchment versus the heather moorland riparian zones that are spatially dominant in the upper catchment. The findings were related to river heat budget studies that provided process detail. Gross changes in stream temperature were affected by the annual cycle of incoming solar radiation and seasonal changes in hydrological and climatological conditions. Inter-annual variation in these controlling variables resulted in inter-annual variability in thermal regime. However, more subtle inter-site differences reflected the impact of site-specific characteristics on various components of the river energy budget. Inter-site variability was most apparent at shorter time scales, during the summer months and for higher stream temperatures. Riparian woodland in the lower catchment had a substantial impact on thermal regime, reducing diel variability (over a period of 24 hours) and temperature extremes. Observed inter-site differences are likely to have a substantial effect on freshwater ecology in general and salmonid fish in particular. Keywords: temperature, thermal regime, forest, salmon, hydrology, Girnock Burn, Cairngorm
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Wilcox, Jeffrey, Emily Bradshaw Marino, Adam Warwick, and Megan Sutton. "Hydrology of a Southern Appalachian Hypocrene Spring-Fed Fen." Environmental and Engineering Geoscience 26, no. 3 (June 15, 2020): 359–66. http://dx.doi.org/10.2113/eeg-2308.
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ABSTRACT Garland Seep is a Southern Appalachian fen that supports a population of federally endangered green pitcher plants (Sarracenia oreophila). The wetland is underlain by clayey stream deposits above fractured bedrock, is located at the base of a mountain slope, and is fed by groundwater that originates as recharge on the adjacent hillslope. Groundwater wells were installed following a hydrologic restoration in the mid-1990s and have been monitored at varying frequencies since that time. The 20+ year record provides evidence that Garland Seep can be classified as a “hypocrene fen,” in which spring flow rarely reaches the ground surface because of low discharge rates and high evapotranspiration (ET). In general, water-level fluctuations followed seasonal ET patterns, with higher water levels in the winter and early spring (when ET is low) and lower levels in the summer and fall. During wetter years, the water table remained near the ground surface for much of the year, with the clay layer underlying the site retaining moisture even after water levels had dropped. The “clay wetting” period was shorter during dryer years and corresponded with a reduction in the number of pitcher plant clumps observed at the site. In addition to the geologic and climatic controls on hydrology, previous landowners used fire to maintain open space for grazing, and The Nature Conservancy has continued the practice to combat woody vegetation and to open the canopy. Prescribed burns reduce ET (at least initially), cause a rise in water levels, and have helped maintain a thriving Sarracenia population.
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Judge, David G., James E. Anderson, Bruce I. McClennan, and Eon T. Park. "Hydrologic design methodologies for prefeasibility studies of small-scale hydro at ungauged sites." Canadian Journal of Civil Engineering 15, no. 3 (June 1, 1988): 289–98. http://dx.doi.org/10.1139/l88-044.
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Hydrologic variables such as available flow for electrical generation and its time distribution, together with flood magnitudes, represent the basis for evaluation of potential hydro sites. Economic viability, especially for small-scale hydro sites is very sensitive to these basic hydrologic variables. Unfortunately, many potential small-scale hydro sites are located on ungauged streams and often the cost of deriving the necessary site specific hydrologic information for design is prohibitive in relation to overall project costs. Therefore, regional techniques have been developed for evaluating the necessary hydrologic variables at a prefeasibility level for small-scale ungauged sites anywhere in Canada. Studies concerned with developing regional techniques for application to feasibility level evaluations have been completed for Atlantic Canada, British Columbia, and Ontario.The methodology can be used to estimate the flow duration curve and the turbinable flow curve for ungauged streams. Equations relating characteristics of the curves to physiographic and climatic parameters have been derived for eleven regions across Canada. An example demonstrating application of the new methodology is included. Key words: hydroelectric power, small-hydro, regional hydrology, ungauged streams, flow duration curves, turbinable flow curves.
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Budi Susilo, Yarianto S. "Management of Site Evaluation: A Lesson Learnt of 10 MW HTGR Experimental Power Reactor (RDE) Project Site Licensing." Journal of Physics: Conference Series 2048, no. 1 (October 1, 2021): 012042. http://dx.doi.org/10.1088/1742-6596/2048/1/012042.
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Abstract In 2013, a pre-project activity of Experimental Power Reactor (RDE Project) was started. The reactor type is a High Temperature Gas-cooled Reactor (HTGR) with a 10 MWth capacity. At present the project has been postponed due to some reason, however, there was an important stage that has been achieved, regarding the site evaluation process to obtain site permits from the Regulatory Body (BAPETEN). Site evaluation is an critical activity that will guarantee the safety of nuclear facilities from natural and human induced external events as well as the safety of population and the environment due to nuclear facility accidents. Site evaluation for the RDE project has the same process as a large NPP project, considering that at the time of the site evaluation process there were no specific regulations that considered a graded approach for a mini-scale NPP. The site evaluation process includes two stages, namely 1). Site Evaluation Program (SEP) and Management System of Site Evaluation (MSSE) Approval and 2) Site Evaluation Approval. SEP is intended to establish the scope and criteria for site evaluation safety. Whereas the Site Evaluation Management System is a managerial instrument that makes site safety as the top priority in each activity and process of RDE site evaluation. BATAN as the project owner delivered the SEP document and MSSE to BAPETEN on March 10, 2014. These documents was intensively discussed by BAPETEN and BATAN to determine agreement on the scope of site evaluation, criteria and management aspects based on site safety considerations. The technical aspects that must be evaluated are seismicity, volcanic hazard, geotechnical and foundation, meteorology, hydrology, human induced events, dispersion and population distribution. This document was approved by BAPETEN on March 2, 2015. Considering the very wide scope with various fields of competence and need supporting data for evaluation, this can not be done only by BATAN experts, it must collaborate with various institution that have competence related to the site aspect. The experts that involved in the site evaluation come from Meteorology and Geophysics Agency (BMKG) for seismic and meteorological aspects, Geospatial Information Agency (BIG) to support geospatial data and ground movements/deformation, Geological Survey Center (PSG) to support geological data and geological structures, Center for Volcanology and Geological Disaster Mitigation (PVMBG) to support volcanic catalog data and volcanic hazard, University to support geotechnical, foundation and hydrology evaluation. BATAN experts from various Centers involved for evaluating topography, human induced events, dispersion, dose assessment, population distribution, emergency preparedness, and technology aspects. Data acquisition activities such as geophysics, drilling, geological mapping, volcanic mapping, hydrology, satellite imagery and digitizing processes are contracted through third parties with guidance developed by the BATAN Expert Team. Considering the very limited time and financial resources availability, in order to achieve the effectiveness of all activities, a special organization was formed to control site evaluation with the BATAN Chairman as Top Management. The Site evaluation document was submitted in two stages. The first stage is administrative completeness and it was declared administratively complete on November 15, 2015. The second step is BAPETEN assessed and evaluated the technical documents submitted to determine the acceptability of the site. The process of evaluating the site evaluation document lasts quite a long and intensive. Finally, the site permit was issued on January 23, 2017. The valuable lessons during the site evaluation project are: 1) It require the same understanding and perception between applicant and regulator regarding the site licensing process; 2) The establishment and implementation of an effective organization; 3) controlling the project schedule.
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Salau, O. B. E., A. Salaudeen, B. A. Gana, I. Zubairu, and S. I. Musa. "Assessment of a New Dam Site for Water Supply Potential in Bauchi Metropolis, Nigeria." Nigerian Journal of Technological Development 18, no. 4 (February 9, 2022): 312–21. http://dx.doi.org/10.4314/njtd.v18i4.7.
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The maximum yield of 90,000 m3 /day from the existing Gubi dam in Bauchi will barely meet the water demand beyond 2030 at an average water use of 100 litres per capita/day. For higher water demand of up to 250 litres per capita/day expected in an urban centre, the existing dam capacity is inadequate, and the demand should grow to 253,102 m3/day by 2037. This is the rationale for this study, which showed the feasibility of a new dam through technical reviews and analysis of topography, hydrology of the site, field and laboratory investigations, computer analyses and designs. Hydrologic simulation of rainfall-runoff processes for 57 years of rainfall data using the Soil Conservation Service (SCS) method gave an annual runoff volume of 59 Mm3 on a stream in Miri, which can be harnessed to assure adequate water supply in the metropolis. This will require the construction of a 25 m high embankment dam. Topographic survey and analysis indicated that the proposed site has good water retention capability. Although net flow adjustment analysis showed a high evaporation loss of up to 13.5 Mm3 annually, seepage loss is expected to be small in view of the underlying basement complex rock formation.
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French, Kirk D., Christopher J. Duffy, and Gopal Bhatt. "The urban hydrology and hydraulic engineering at the classic maya site of Palenque." Water History 5, no. 1 (January 4, 2013): 43–69. http://dx.doi.org/10.1007/s12685-012-0069-4.
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Edem, I. D., and U. C. Udo-Inyang. "Depositional Hydrology in the Subtidal Site of Fertilizer Company: Grain-Size Hydraulics Approach." International Letters of Natural Sciences 49 (November 2015): 7–18. http://dx.doi.org/10.18052/www.scipress.com/ilns.49.7.
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Still very much terra incognita, grain shape has the potential to evaluate sedimentary transport, provenance, and depositional environments. There are several standard measures of grain shape. The results revealed that, the soil is non-uniformly graded with tortuous pore geometry due to overlaying layers, even though the grain size varied from granular grained size to medium grained. Therefore the soil under study is not easily moved by transporting medium. Also, there is significant effect of redox potential (ORP) on the electron availability of nitrate and the tested heavy metals (Cd, Ni, Pb, and Cu) were below detection limit of analytical equipment. The least reduced conditions occurred in stations; 2 (control), 3, 6, 15, 18 and 19 with minimum values of 99 to 110 mv. The absence of significant fungi populations in the soil indicates that the soils have no potential to biodegrade hydrocarbons when they are released into the environment.
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Edem, I. D., and U. C. Udo-Inyang. "Depositional Hydrology in the Subtidal Site of Fertilizer Company: Grain-Size Hydraulics Approach." International Letters of Natural Sciences 49 (November 24, 2015): 7–18. http://dx.doi.org/10.56431/p-t9f5qf.
Full textAbstract:
Still very much terra incognita, grain shape has the potential to evaluate sedimentary transport, provenance, and depositional environments. There are several standard measures of grain shape. The results revealed that, the soil is non-uniformly graded with tortuous pore geometry due to overlaying layers, even though the grain size varied from granular grained size to medium grained. Therefore the soil under study is not easily moved by transporting medium. Also, there is significant effect of redox potential (ORP) on the electron availability of nitrate and the tested heavy metals (Cd, Ni, Pb, and Cu) were below detection limit of analytical equipment. The least reduced conditions occurred in stations; 2 (control), 3, 6, 15, 18 and 19 with minimum values of 99 to 110 mv. The absence of significant fungi populations in the soil indicates that the soils have no potential to biodegrade hydrocarbons when they are released into the environment.
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Elshafei, Y., M. Sivapalan, M. Tonts, and M. R. Hipsey. "A prototype framework for models of socio-hydrology: identification of key feedback loops and parameterisation approach." Hydrology and Earth System Sciences 18, no. 6 (June 13, 2014): 2141–66. http://dx.doi.org/10.5194/hess-18-2141-2014.
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Abstract. It is increasingly acknowledged that, in order to sustainably manage global freshwater resources, it is critical that we better understand the nature of human–hydrology interactions at the broader catchment system scale. Yet to date, a generic conceptual framework for building models of catchment systems that include adequate representation of socioeconomic systems – and the dynamic feedbacks between human and natural systems – has remained elusive. In an attempt to work towards such a model, this paper outlines a generic framework for models of socio-hydrology applicable to agricultural catchments, made up of six key components that combine to form the coupled system dynamics: namely, catchment hydrology, population, economics, environment, socioeconomic sensitivity and collective response. The conceptual framework posits two novel constructs: (i) a composite socioeconomic driving variable, termed the Community Sensitivity state variable, which seeks to capture the perceived level of threat to a community's quality of life, and acts as a key link tying together one of the fundamental feedback loops of the coupled system, and (ii) a Behavioural Response variable as the observable feedback mechanism, which reflects land and water management decisions relevant to the hydrological context. The framework makes a further contribution through the introduction of three macro-scale parameters that enable it to normalise for differences in climate, socioeconomic and political gradients across study sites. In this way, the framework provides for both macro-scale contextual parameters, which allow for comparative studies to be undertaken, and catchment-specific conditions, by way of tailored "closure relationships", in order to ensure that site-specific and application-specific contexts of socio-hydrologic problems can be accommodated. To demonstrate how such a framework would be applied, two socio-hydrological case studies, taken from the Australian experience, are presented and the parameterisation approach that would be taken in each case is discussed. Preliminary findings in the case studies lend support to the conceptual theories outlined in the framework. It is envisioned that the application of this framework across study sites and gradients will aid in developing our understanding of the fundamental interactions and feedbacks in such complex human–hydrology systems, and allow hydrologists to improve social–ecological systems modelling through better representation of human feedbacks on hydrological processes.
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Wang, Hai Jun, Zhi Cheng Xue, and Zi Qian Han. "Temporary Support Design on Large-Span Casting Box Girder of the Songpu Bridge." Applied Mechanics and Materials 99-100 (September 2011): 304–7. http://dx.doi.org/10.4028/www.scientific.net/amm.99-100.304.
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By the study of construction of casting box girder of Songpu Bridge in Harbin, and the actual site geology, hydrology and the corresponding norms, this paper designed temporary support with the method of allowable stress. It was proved that the temporary support met the need of the site construction, both to ensure casting construction quality, but also save construction costs and speed up the construction progress, which provided a new way for the construction of large-span continuous box girder.
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Bisbing, Sarah M., and David V. D’Amore. "Nitrogen dynamics vary across hydrologic gradients and by forest community composition in the perhumid coastal temperate rainforest of southeast Alaska." Canadian Journal of Forest Research 48, no. 2 (February 2018): 180–91. http://dx.doi.org/10.1139/cjfr-2017-0178.
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Nitrogen (N) limitation constrains plant growth, but complex interactions among species and ecosystems hinder our ability to identify primary drivers of N availability. Hydrologic, biogeochemical, and ecological processes interact spatially and temporally, requiring measurements of N across diverse ecosystem types and as a function of both site conditions and vegetation composition. We measured initial exchangeable and mineralized N along a hydrologic gradient in the Alaskan perhumid coastal temperate rainforest to test a conceptual model of linkages between N availability and landscape, hydrologic, and ecosystem characteristics in temperate forests. Mineralization was closely associated with inorganic N concentrations. Inorganic N as NH4+ generally increased with increasing depth to groundwater but was strongly determined by plant–water interactions. Exchangeable and mineralized N were closely linked to tree species, forest biomass, and hydrologic regime regardless of ecosystem type. The emergence of tree species as indicators of N cycling highlights the effect that species have on nutrient dynamics, while the trend of increasing inorganic N with increasing soil saturation points to the role of hydrology in driving N availability. Our research quantified N dynamics for an understudied, yet critical, system and provides a framework for exploring feedbacks among soil saturation, forest composition, and nutrient cycling in temperate forests.
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Savenije, H. H. G. "HESS Opinions "The art of hydrology"*." Hydrology and Earth System Sciences 13, no. 2 (February 18, 2009): 157–61. http://dx.doi.org/10.5194/hess-13-157-2009.
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Abstract. Hydrological modelling is the same as developing and encoding a hydrological theory. A hydrological model is not a tool but a hypothesis. The whole discussion about the inadequacy of hydrological models we have witnessed of late, is related to the wrong concept of what a model is. Good models don't exist. Instead of looking for the "best" model, we should aim at developing better models. The process of modelling should be top-down, learning from the data while at the same time connection should be established with underlying physical theory (bottom-up). As a result of heterogeneity occurring at all scales in hydrology, there always remains a need for calibration of models. This implies that we need tailor-made and site-specific models. Only flexible models are fit for this modelling process, as opposed to most of the established software or "one-size-fits-all" models. The process of modelling requires imagination, inspiration, creativity, ingenuity, experience and skill. These are qualities that belong to the field of art. Hydrology is an art as much as it is science and engineering.
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Prudhomme, C., T. Haxton, S. Crooks, C. Jackson, A. Barkwith, J. Williamson, J. Kelvin, et al. "Future Flows Hydrology: an ensemble of daily river flow and monthly groundwater levels for use for climate change impact assessment across Great Britain." Earth System Science Data 5, no. 1 (March 13, 2013): 101–7. http://dx.doi.org/10.5194/essd-5-101-2013.
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Abstract. The dataset Future Flows Hydrology was developed as part of the project "Future Flows and Groundwater Levels'' to provide a consistent set of transient daily river flow and monthly groundwater level projections across England, Wales and Scotland to enable the investigation of the role of climate variability on river flow and groundwater levels nationally and how this may change in the future. Future Flows Hydrology is derived from Future Flows Climate, a national ensemble projection derived from the Hadley Centre's ensemble projection HadRM3-PPE to provide a consistent set of climate change projections for the whole of Great Britain at both space and time resolutions appropriate for hydrological applications. Three hydrological models and one groundwater level model were used to derive Future Flows Hydrology, with 30 river sites simulated by two hydrological models to enable assessment of hydrological modelling uncertainty in studying the impact of climate change on the hydrology. Future Flows Hydrology contains an 11-member ensemble of transient projections from January 1951 to December 2098, each associated with a single realisation from a different variant of HadRM3 and a single hydrological model. Daily river flows are provided for 281 river catchments and monthly groundwater levels at 24 boreholes as .csv files containing all 11 ensemble members. When separate simulations are done with two hydrological models, two separate .csv files are provided. Because of potential biases in the climate–hydrology modelling chain, catchment fact sheets are associated with each ensemble. These contain information on the uncertainty associated with the hydrological modelling when driven using observed climate and Future Flows Climate for a period representative of the reference time slice 1961–1990 as described by key hydrological statistics. Graphs of projected changes for selected hydrological indicators are also provided for the 2050s time slice. Limitations associated with the dataset are provided, along with practical recommendation of use. Future Flows Hydrology is freely available for non-commercial use under certain licensing conditions. For each study site, catchment averages of daily precipitation and monthly potential evapotranspiration, used to drive the hydrological models, are made available, so that hydrological modelling uncertainty under climate change conditions can be explored further. doi:10.5285/f3723162-4fed-4d9d-92c6-dd17412fa37b
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Prudhomme, C., T. Haxton, S. Crooks, C. Jackson, A. Barkwith, J. Williamson, J. Kelvin, et al. "Future Flows Hydrology: an ensemble of daily river flow and monthly groundwater levels for use for climate change impact assessment across Great Britain." Earth System Science Data Discussions 5, no. 2 (December 4, 2012): 1159–78. http://dx.doi.org/10.5194/essdd-5-1159-2012.
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Abstract. The dataset Future Flows Hydrology was developed as part of the project "Future Flows and Groundwater Levels" to provide a consistent set of transient daily river flow and monthly groundwater levels projections across England, Wales and Scotland to enable the investigation of the role of climate variability on river flow and groundwater levels nationally and how this may change in the future. Future Flows Hydrology is derived from Future Flows Climate, a national ensemble projection derived from the Hadley Centre's ensemble projection HadRM3-PPE to provide a consistent set of climate change projections for the whole of Great Britain at both space and time resolutions appropriate for hydrological applications. Three hydrological models and one groundwater level model were used to derive Future Flows Hydrology, with 30 river sites simulated by two hydrological models to enable assessment of hydrological modelling uncertainty in studying the impact of climate change on the hydrology. Future Flows Hydrology contains an 11-member ensemble of transient projections from January 1951 to December 2098, each associated with a single realisation from a different variant of HadRM3 and a single hydrological model. Daily river flows are provided for 281 river catchments and monthly groundwater levels at 24 boreholes as .csv files containing all 11 ensemble members. When separate simulations are done with two hydrological models, two separate .csv files are provided. Because of potential biases in the climate-hydrology modelling chain, catchment fact sheets are associated with each ensemble. These contain information on the uncertainty associated with the hydrological modelling when driven using observed climate and Future Flows Climate for a period representative of the reference time slice 1961–1990 as described by key hydrological statistics. Graphs of projected changes for selected hydrological indicators are also provided for the 2050s time slice. Limitations associated with the dataset are provided, along with practical recommendation of use. Future Flows Hydrology is freely available for non-commercial use under certain licensing conditions. For each study site, catchment averages of daily precipitation and monthly potential evapotranspiration, used to drive the hydrological models, are made available, so that hydrological modelling uncertainty under climate change conditions can be explored further. doi:10.5285/f3723162-4fed-4d9d-92c6-dd17412fa37b.
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Baker, A., C. Bradley, S. J. Phipps, M. Fischer, I. J. Fairchild, L. Fuller, C. Spötl, and C. Azcurra. "Millennial-length forward models and pseudoproxies of stalagmite δ<sup>18</sup>O: an example from NW Scotland." Climate of the Past 8, no. 4 (July 11, 2012): 1153–67. http://dx.doi.org/10.5194/cp-8-1153-2012.
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Abstract. The stable oxygen isotope parameter δ18O remains the most widely utilised speleothem proxy for past climate reconstructions. Uncertainty can be introduced into stalagmite δ18O from a number of factors, one of which is the heterogeneity of groundwater flow in karstified aquifers. Here, we present a lumped parameter hydrological model, KarstFor, which is capable of generating monthly simulations of surface water – ground water – stalagmite δ18O for more than thousand-year time periods. Using a variety of climate input series, we use this model for the first time to compare observational with modelled (pseudoproxy) stalagmite δ18O series for a site at Assynt, NW Scotland, where our knowledge of δ18O systematics is relatively well understood. The use of forward modelling allows us to quantify the relative contributions of climate, peat and karst hydrology, and disequilibrium effects in stalagmite δ18O, from which we can identify potential stalagmite δ18O responses to climate variability. Comparison of the modelled and actual stalagmite δ18O for two stalagmites from the site demonstrates that, for the period of overlapping growth, the two series do not correlate with one another, but forward modelling demonstrates that this falls within the range explicable by differences in flow routing to the stalagmites. Pseudoproxy δ18O stalagmite series highlight the potential significance of peat hydrology in controlling stalagmite δ18O over the last 1000 yr at this site.
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Baker, A., C. Bradley, S. J. Phipps, M. Fischer, I. J. Fairchild, L. Fuller, C. Spötl, and C. Azcurra. "Millennial-length forward models and pseudoproxies of stalagmite δ<sup>18</sup>O: an example from NW Scotland." Climate of the Past Discussions 8, no. 2 (March 12, 2012): 869–907. http://dx.doi.org/10.5194/cpd-8-869-2012.
Full textAbstract:
Abstract. The stable oxygen isotope parameter δ18O remains the most widely utilised speleothem proxy for past climate reconstructions. Uncertainty can be introduced into stalagmite δ18O from a number of factors, one of which is the heterogeneity of groundwater flow in karstified aquifers. Here, we present a lumped parameter hydrological model, KarstFor, which is capable of generating monthly simulations of surface water – ground water – stalagmite δ18O for more than thousand year time periods. Using a variety of climate input series, we use this model for the first time to compare observational with modelled (pseudoproxy) stalagmite δ18O series for a site at Assynt, NW Scotland, where our knowledge of δ18O systematics is relatively well understood. The use of forward modelling allows us to quantify the relative contributions of climate, peat and karst hydrology, and disequilibrium effects in stalagmite δ18O, from which we can identify potential stalagmite δ18O responses to climate variability. Comparison of the modelled and actual stalagmite δ18O for two stalagmites from the site demonstrates that for the period of overlapping growth, the two series do not correlate with one another, but forward modelling demonstrates that this falls within the range explicable by differences in flow routing to the stalagmites. Pseudoproxy δ18O stalagmite series highlight the potential significance of peat hydrology in controlling stalagmite δ18O over the last 1000 years at this site.
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Savabi, M. R., W. J. Rawls, and R. W. Knight. "Water Erosion Prediction Project (WEPP) Rangeland Hydrology Component Evaluation on a Texas Range Site." Journal of Range Management 48, no. 6 (November 1995): 535. http://dx.doi.org/10.2307/4003066.
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Daoxian, Yuan, C. Drogue, Dai Aide, Lao Wenke, Cai Wutian, P. Bidaux, and M. Razack. "Hydrology of the Karst aquifer at the experimental site of Guilin in southern China." Journal of Hydrology 115, no. 1-4 (July 1990): 285–96. http://dx.doi.org/10.1016/0022-1694(90)90210-o.
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