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Статті в журналах з теми "Depositions in wetlands":
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Raffield, Ben. "‘A River of Knives and Swords': Ritually Deposited Weapons in English Watercourses and Wetlands during the Viking Age." European Journal of Archaeology 17, no. 4 (2014): 634–55. http://dx.doi.org/10.1179/1461957114y.0000000066.
This paper discusses the deposition of weapons in English rivers and wetlands during the Viking Age. Such finds have been extensively studied in Scandinavia but have rarely been academically discussed in Britain. It can be argued that the arrival of the Scandinavians in ninth- to eleventh-century Britain precipitated a marked increase in depositions of a ‘pagan’ nature. Despite deep-rooted, institutionalized Christianity having dominated England for some time, it is possible that pagan beliefs were dormant but not forgotten, with the Scandinavian arrival triggering their resurgence. Weapons form a large number of ritual depositions, with seventy deposits being mapped geographically to identify distributional patterns across the landscape. It is suggested here that ‘liminal' depositions in Viking Age Scandinavia provide an interpretative model for these finds. Given the context of endemic conflict and territorial consolidation within which they may have been deposited in England, this material can shed new light on attitudes to landscapes subject to conflict and consolidation.
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Scharin, H. "Nutrient management for coastal zones: a case study of the nitrogen load to the Stockholm Archipelago." Water Science and Technology 45, no. 9 (May 1, 2002): 309–15. http://dx.doi.org/10.2166/wst.2002.0266.
This study investigates cost-effective solutions of decreasing the nutrient load to a coastal area, using a drainage basin approach. The study is applied to the Stockholm Archipelago, a coastal area of the Baltic Sea suffering from eutrophication caused by the load of nutrients entering the area. Nitrogen is the nutrient of concern in this study since it is the limiting nutrient of the Archipelago. The main sources of nitrogen are wastewater plants, agriculture, and atmospheric depositions. The final impact of a deposition depends on the buffering capabilities it is subject to on its trajectory from the source to the recipient. This is the reason for using a recipient oriented approach, in which the focus is to reduce the final impact of a deposition. The model integrates data over hydrology, land cover, land use, and economy in order to find the optimal allocation of measures. Results indicate that in order to achieve cost effectiveness, the major part of nitrogen load reduction to the Archipelago should be done at the wastewater plants and by constructing wetlands. The minimum annual cost of reaching a 50% reduction of the load to the Archipelago was estimated to around 191 million Swedish crowns (around $ 19 million).
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Bhuju, DR, S. Sharma, PK Jha, and NP Gaire. "Scientific Discourse of Lakes in Nepal." Nepal Journal of Science and Technology 13, no. 2 (March 8, 2013): 147–58. http://dx.doi.org/10.3126/njst.v13i2.7728.
Over 5,000 standing water bodies, including those <1 ha and spread in 74 districts of Nepal have been scanned on the topographic sheets (scale of 1:125,000). Majority of these lakes or ponds are either in the high altitudes (above 3,000 m) or in lowland Tarai (below 500 m). In a literature review we found over 163 research studies conducted since the first study of lakes in 1969 in Khumbu region, majority being at the initiative of national academia, their faculties and graduate students. However, a complete inventory of Nepal’s lakes is still lacking. Their characteristics and distinction from wetlands are also to be defined as the existing laws and rules do not protect lakes or ponds categorically, rather they are blanketed under wetlands and/or other river like water resources. Research observations have shown that acid depositions are the most likely source of pollution affecting high altitude lakes in the Himalayan regions during spring. Their value as religious sites has also caused anthropogenic alteration in nutrient concentrations and biological assemblages of the lake. Encroachment to the lakes/ponds is rampant to which the natural processes of sedimentation, alien species invasion or any kind of obliteration become supportive. Capacity building, knowledge generation and threat management are vital to protect these natural heritages from untimely demise. Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 147-158 DOI: http://dx.doi.org/10.3126/njst.v13i2.7728
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Qin, Tian-Jian, Yu-Ting Guan, Ming-Xiang Zhang, Hong-Li Li, and Fei-Hai Yu. "Sediment type and nitrogen deposition affect the relationship between Alternanthera philoxeroides and experimental wetland plant communities." Marine and Freshwater Research 69, no. 5 (2018): 811. http://dx.doi.org/10.1071/mf17335.
Wetlands have been demonstrated to be susceptible to invasions. Nutrient availability of wetland sediment is strongly affected by both sediment type and nitrogen deposition. We performed a greenhouse experiment to investigate the main effects and interactions between the presence of Alternanthera philoxeroides, sediment type and nitrogen deposition on biomass and evenness of experimental wetland plant communities. We established two types of plant communities, specifically wetland plant communities without and with A. philoxeroides, in two different sediment types crossed with two nitrogen deposition treatments. Experimental wetland plant communities consisted of four native or naturalised wetland species. Sediment type and nitrogen deposition significantly promoted A. philoxeroides growth. At the community level, the presence of A. philoxeroides decreased the total biomass of wetland plant species and increased community evenness, whereas sediment type significantly decreased evenness. At the species level, the presence of A. philoxeroides significantly decreased total biomass of Iris wilsonii and increased total biomass of Pontederia cordata. However, the interaction between invasion and nitrogen deposition significantly increased total biomass of Butomus umbellatus. These findings suggest that both sediment type and nitrogen deposition promote A. philoxeroides growth and exacerbate A. philoxeroides invasion into wetland plant communities. However, the presence of A. philoxeroides can increase the evenness of the wetland plant communities at a small scale by suppressing dominant species. The findings of the present study provide insights into the management of A. philoxeroides in wetlands.
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Crowder, A. A., and S. M. Macfie. "Seasonal deposition of ferric hydroxide plaque on roots of wetland plants." Canadian Journal of Botany 64, no. 9 (September 1, 1986): 2120–24. http://dx.doi.org/10.1139/b86-279.
In three wetlands in southeastern Ontario, ferric hydroxide was deposited on the roots of Typha latifolia (maximum, 67 × 103 ppm); in four other wetlands, deposition was negligible (< 103 ppm). Iron deposition was seasonal, with the peak period in July–August corresponding to peak biomass production of shoots. In one wetland where Carex rostrata and Phragmites australis occurred, seasonal plaque formation was similar. Plaque formation was not obviously related to Eh and pH regimes.
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Žáková, Z., D. Beránková, E. Kocková, and P. Kríž. "Influence of Diffuse Pollution on the Eutrophication and Water Quality of Reservoirs in the Morava River Basin." Water Science and Technology 28, no. 3-5 (August 1, 1993): 79–90. http://dx.doi.org/10.2166/wst.1993.0406.
Diffuse (nonpoint) pollution from the river basin is responsible for a substantial part of Czech reservoirs' deterioration caused by eutrophication and water pollution. The research results of two model drinking water supply reservoirs (different area and depth) in the Morava river basin showed that the main nutrient sources in the period 1960-1991 were: agricultural land use (overland and subsurface transport of nutrients, effects of drainage and erosion), point sources (urban activities, agricultural farms) and atmospheric depositions of N and P compounds. The accelerated eutrophication was manifested by the increasing development of phytoplankton. The main problems entail occurrence of toxic species of Cyanophyta/Cyanobacteria (blue-green algae) Aphanizomenon flos-aquae, Microcystis aeruginosa and some other species (e.g. Pseudanabaena limnetica). In the small and shallow drinking water reservoir of Ludkovice the living algae penetrated drinking water. In the deep reservoir of Vír the situation was more favourable. The increase of nutrient input (N,P) during the period 1969-1992 was highly significant Various measures have been proposed to slow the reservoir eutrophication (sustainable use of land, best management practices - soil retention, buffer strips, constructed wetlands etc.).
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Cooke, James G. "Nutrient Transformations in a Natural Wetland Receiving Sewage Effluent and the Implications for Waste Treatment." Water Science and Technology 29, no. 4 (February 1, 1994): 209–17. http://dx.doi.org/10.2166/wst.1994.0193.
The processes influencing nutrient (phosphorus and nitrogen) renovation in a natural wetland which had received oxidation pond effluent for twelve years were studied, and compared with current literature perceptions. Mass transport studies showed that 30–70% of the influent P was removed from the water column, which was much greater than published values suggest could be predicted for this highly loaded (∼ 34 g P m−2 y−1) system. Sediment traps studies showed that deposition of particulate P immediately downstream of confluences with arms of the wetland not impacted by sewage effluent (natural wetlands) was the dominant cause of P removal. Separation of the deposited-P into chemically definable fractions along with studies on the water chemistry, suggested that P deposition was associated with iron-organic complexes contributed dominantly from the natural wetlands. Considerable spatial and temporal heterogeneity was also demonstrated for nitrogen transformations. During summer most of the influent-N was in nitrate form which was all transformed during passage through the wetland. Isotope (15N) dilution studies indicated that ∼ 60–70% was denitrified, 25–35% converted to ammonium (dissimilatory reduction), and 5–10% assimilated. For most of the year, however, influent N was mainly in reduced forms. Despite this, significant quantities of nitrate were exported from the wetland especially at higher flows in spring-early summer. Assays on the sediment showed that there was a marked increase in nitrification activity at the confluence with natural wetlands. It is suggested that marked changes in sediment redox potential at these confluence sites provide ideal conditions for nitrification of sorbed ammonium which is subsequently flushed from the system in ‘flood events’. The distribution and type of nutrient processing observed in this wetland are attributable to its configuration. The implication of these results to the sustainability of nutrient renovation in wetland treatment systems is discussed.
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Maynard, J. J., A. T. O'Geen, and R. A. Dahlgren. "Agricultural induced impacts on soil carbon cycling and sequestration in a seasonally saturated wetland." Biogeosciences Discussions 8, no. 3 (June 29, 2011): 6031–75. http://dx.doi.org/10.5194/bgd-8-6031-2011.
Abstract. The fate of organic carbon (C) lost by erosion is not well understood in agricultural settings. Recent models suggest that wetlands and other small water bodies may serve as important long-term sinks of eroded C, receiving ~30 % of all eroded material in the US. To better understand the role of seasonally-saturated wetlands in sequestering eroded C, we examined the spatial and temporal dynamics of C and sediment accumulation in a 13-yr-old constructed wetland used to treat agricultural runoff. The fate of C sequestered within deposited sediment was modeled using point-sampling, remote sensing, and geostatistics. Using a spatially-explicit sampling design, annual net rates of sedimentation and above ground biomass were measured during two contrasting years (vegetated, 2004 vs. non-vegetated, 2005), followed by collection of sediment cores to the antecedent soil layer, representing 13 yr of sediment and C accumulation. We documented high annual variation in the relative contribution of endogenous and exogenous C sources, as well as absolute rates of sediment and C deposition. This annual variation, however, was muted in the long-term (13-yr) sediment record, which showed consistent vertical patterns of uniform C distribution (~14 g kg−1) and δ13C signatures in high depositional environments. This was in contrast to low depositional environments which had high levels of surface C enrichment (20–35 g kg−1) underlain by C depleted (5–10 g kg−1) sediments and an increasing δ13C signature with depth indicating increasing decomposition. These results highlight the importance of sedimentation in physically protecting soil organic carbon and its role in controlling the long-term C concentration of seasonally-saturated wetland soils. While significant enrichment of surface sediments with endogenous C occurred in newly deposited sediment (i.e., 125 kg m2 in 2004), fluctuating cycles of flooding and drying maintained the long-term C concentration at the same level as inflowing sediment (i.e., 14 g kg−1), indicating no additional long-term storage of endogenous C. These results demonstrate that constructed flow-through wetlands can serve as important sinks for eroded C and sediment in agricultural landscapes, however, additional C sequestration via enrichment from endogenous sources may be limited in seasonally-saturated wetlands due to rapid decomposition during drying cycles.
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Maynard, J. J., R. A. Dahlgren, and A. T. O'Geen. "Soil carbon cycling and sequestration in a seasonally saturated wetland receiving agricultural runoff." Biogeosciences 8, no. 11 (November 23, 2011): 3391–406. http://dx.doi.org/10.5194/bg-8-3391-2011.
Abstract. The fate of organic carbon (C) lost by erosion is not well understood in agricultural settings. Recent models suggest that wetlands and other small water bodies may serve as important long-term sinks of eroded C, receiving ~30 % of all eroded material in the US. To better understand the role of seasonally-saturated wetlands in sequestering eroded C, we examined the spatial and temporal dynamics of C and sediment accumulation in a 13-year-old constructed wetland used to treat agricultural runoff. The fate of C sequestered within deposited sediment was modeled using point-sampling, remote sensing, and geostatistics. Using a spatially-explicit sampling design, annual net rates of sedimentation and above-ground biomass were measured during two contrasting years (vegetated (2004) vs. non-vegetated (2005)), followed by collection of sediment cores to the antecedent soil layer, representing 13 years of sediment and C accumulation. We documented high annual variation in the relative contribution of endogenous and exogenous C sources, as well as absolute rates of sediment and C deposition. This annual variation, however, was muted in the long-term (13 yr) sediment record, which showed consistent vertical patterns of uniform C distribution (~14 g kg–1) and δ13C signatures in high depositional environments. This was in contrast to low depositional environments which had high levels of surface C enrichment (20–35 g kg–1) underlain by C depleted (5–10 g kg–1) sediments and an increasing δ13C signature with depth indicating increased decomposition. These results highlight the importance of sedimentation in physically protecting soil organic carbon and its role in controlling the long-term C concentration of seasonally-saturated wetland soils. While significant enrichment of surface sediments with endogenous C occurred in newly deposited sediment (i.e., 125 kg m2 in 2004), fluctuating cycles of flooding and drying maintained the long-term C concentration at the same level as inflowing sediment (i.e., 14 g kg–1), indicating no additional long-term storage of endogenous C. These results demonstrate that constructed flow-through wetlands can serve as important sinks for eroded C and sediment in agricultural landscapes, however, additional C sequestration via enrichment from endogenous sources may be limited in seasonally-saturated wetlands due to rapid decomposition during drying cycles.
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St. Louis, Vincent L., John W. M. Rudd, Carol A. Kelly, Ken G. Beaty, Nicholas S. Bloom, and Robert J. Flett. "Importance of Wetlands as Sources of Methyl Mercury to Boreal Forest Ecosystems." Canadian Journal of Fisheries and Aquatic Sciences 51, no. 5 (May 1, 1994): 1065–76. http://dx.doi.org/10.1139/f94-106.
Wetlands were found to be important sources of methyl mercury to the boreal forest ecosystem. Yields of methyl mercury were about 26–79 times higher from wetland portions of catchments (1.84–5.55 mg∙ha−1∙yr−1) than from purely upland areas (0.07 mg∙ha−1∙yr−1). Mass-balance estimates using methyl mercury inputs in wet deposition and outputs in runoff water indicated that purely upland catchments and lakes were sites of methyl mercury retention or demethylation, while catchments with wetland areas were sites of net methyl mercury production. These observations may explain the high concentrations of mercury in fish taken from lakes that are high in colour because they receive water from wetlands. There was no relationship between the concentration of total mercury and the concentration of methyl mercury in runoff water. Total mercury yields were low from a wetland-dominated catchment, higher from a combination upland/riparian wetland catchment, and highest from a purely upland catchment. The opposite was true for methyl mercury yields from these same catchments. This indicates that environmental factors other than total mercury concentration are controlling the production and loss of methyl mercury from catchments.
Bodin, Markus. "Rituella depositioner i våtmark under vikingatid : Kan politisk och religiös centralisering kopplas till kontroll av ritualer?" Thesis, Uppsala universitet, Institutionen för arkeologi och antik historia, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-446373.
To date, previous discussions of the practise of ”weapon deposition” in prehistoric Scandinavia have focused primarily on the Roman Iron Age. The focus of these investigations have been the large offerings of weapons in bogs, which were presumably taken from enemies defeated in battle. Until recently, these particular kind of ritual practises were thought to have ceased in the middle of the 6th century. It is now widely acknowledged, however, that this sort of ritual practises did not simply dissappear, but instead re-emerged during the Vendel- and Viking age in a changed state. These rites, which are frequently associated with elite groups and so called ”central places” are embodied, for example, in the weapons and other valuable objects deposited in the lake adjacent to the Late Iron Age magnate site at Tissø, Denmark. Similar finds have been recovered in Scania and Gotland, but these practises have not received enough attention compared to other ritual aspects of the Viking Age. This essay therefore aims to investigate the ideologies and motivations underpinning these rites, and provide a reassessment of their possible connection to elites, political and religious centralization, and central places/manorial sites.
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Anderson, Christopher John. "The influence of hydrology and time on productivity and soil development of created and restored wetlands." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1132540084.
Eulie, Devon Olivola. "Sediment deposition and availability in the riparian wetlands of the Cape Fear River." View electronic thesis, 2008. http://dl.uncw.edu/etd/2008-1/eulied/devoneulie.pdf.
Brenda, Leady Sue Simmers. "Historic Patterns of Deposition and Biomagnification of Mercury in Selected Wetland Systems." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1372863246.
Crook, Hannah D. "Carbon and nitrogen cycling in upland wetlands : impacts of changing climate and atmospheric nitrogen deposition." Thesis, University of Reading, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412169.
Horton, Kimberly. "Roadway effects on the hydrologic regime of temporary wetlands in the Missouri River floodplain in Missouri." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4241.
Thesis (M.S.)--University of Missouri-Columbia, 2005. The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (January 11, 2007) Includes bibliographical references.
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Smith, Caitlin Langworthy. "Effects of Sediment Removal on Vegetation Communities in Prairie Pothole Wetlands in North Dakota." Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/29314.
The goal of this study was to assess effects of sediment removal on vegetation communities in Prairie Pothole wetlands in North Dakota to determine if this management technique is providing desired results to create conditions for ideal vegetation communities in wetlands that will benefit wildlife. This project consists of vegetation surveys from seasonal wetlands located in Benson, Eddy. Towner. and Wells counties in North Dakota. Three types of wetlands were surveyed: natural (reference), excavated (treatment), and converted cropland. Vegetation surveys were completed in the shallow marsh and wet meadow zones of seasonal wetlands. Sites were sampled using a modified Daubenmire method. Aerial photos were assessed to determine the occurrence of drawdown cycles in wetland sites. Plant communities were analyzed using non-metric multidimensional scaling and multi-response permutation procedure was used to make comparisons between sites. The wet meadow zones and shallow marsh zones of the three types of wetlands were all significantly different (p<0.016) from one another. In general, restored wetlands show vegetation trends that liken natural wetlands while those that have been allowed to recover without restoration tend to be cattail choked. When examining hybrid cattail specifically visual obstruction scores were approximately four times greater in converted cropland sites versus treatment or reference sites. Vegetation composition indicates hydrologic conditions (fresh to brackish conditions) of specific sites and regional distribution are likely influential factors in wetland plant establishment. North Dakota State University U.S. Fish and Wildlife Service Ducks Unlimited
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Davis, Melissa J. "QUANTIFYING CURRENT SEDIMENT DEPOSITION, LEGACY SEDIMENTS, AND PRE-IMPOUNDMENT VERTICAL ACCRETION AND CARBON DYNAMICS FOLLOWING DAM REMOVAL IN A RECENTLY RESTORED TIDAL FRESHWATER WETLAND." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/5015.
Damming disrupts natural sediment flow to downstream resulting in legacy sediment accumulation. Legacy sediments have been well investigated in streams throughout the Piedmont region; however, there is no research of legacy sediments following dam removal in low-gradient Coastal Plain streams. Research objectives were to: characterize legacy sediments in a low-gradient stream restoration, quantify pre-impoundment accretion and carbon dynamics, and assess current sediment deposition rates via 14C analyses within sediment cores and sediment collection tiles. Carbon accumulation and accretion rates of modern tidal sediment have reached that of the tidal relic benchmark and current sediment deposition rates are similar between the natural reference and restored tidal wetlands. At this site, the pattern of legacy sediment accumulation and stream incision was reversed relative to previous studies in higher gradient systems. Results suggest in dam impacted Coastal Plain streams, legacy sediment may become a benefit rather than a liability for downstream tidal wetlands.
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Mahmoudi, Mehrnoosh. "Numerical Modeling of the Effects of Hydrologic Conditions and Sediment Transport on Geomorphic Patterns in Wetlands." FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1656.
This dissertation focused on developing a numerical model of spatial and temporal changes in bed morphology of ridge and slough features in wetlands with respect to hydrology and sediment transport when a sudden change in hydrologic condition occurs. The specific objectives of this research were: (1) developing a two-dimensional hydrology model to simulate the spatial distribution of flow depth and velocity over time when a pulsed flow condition is applied, (2) developing a process-based numerical model of sediment transport coupled with flow depth and velocity in wetland ecosystems, and (3) use the developed model to explore how sediment transport may affect the changes in bed elevation of ridge and slough landscape patterns observed in wetlands when a conditional pulsed flow was applied. The results revealed the areas within deep sloughs where flow velocities and directions change continuously. This caused enhanced mixing areas within the deep slough. These mixing areas may have had the potential to affect processes such as sediment redistribution and nutrient transport. The simulation results of solute/sediment transport model also supported the existence of areas within the domain where the mixing processes happened. These areas may have caused that nutrients and suspended particles stay longer time rather than entraining toward downstream and exiting the system. The results of bed simulation have shown very small magnitude of change in bed elevation inside deep slough and no changes on the ridge portion of the study area, when a conditional pulsed flow is applied. These findings may suggest that implementing pulsed flow condition did not increase suspended sediment concentration, which results in insignificant changes in bed morphology of a ridge and slough landscape. Therefore sediment transport may not play an important role in wetland bed morphology and ridge and slough stability. Results from the model development and numerical simulations from this research will provide an improved understanding of how wetland features such as ridge may have formed and degraded by changes in water management that resulted from increasing human activity in wetlands such as The Florida Everglades, over the past decades.
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Messing, Paul. "Pesticides in the air, atmospheric deposits, and surface waters of Canada." 2015. http://hdl.handle.net/1993/30175.
In Canada, more than 35 million kilograms of pesticide active ingredients are applied annually on agricultural land with about 84% of this mass applied in the Canadian Prairies Provinces. Pesticide residues may become airborne through post-volatilization losses from land, water or vegetative surfaces, via wind-eroded soil, and by spray drift during pesticide application. Once in the air, pesticides may be dispersed and transported as parent molecules or as degradation products. Currently used and legacy pesticide air concentrations were measured in the agricultural region of the Prairie Provinces and the northern subarctic and arctic regions of Canada in 2005 and 2007. More intensive air sampling was conducted across the province of Manitoba in 2008 and 2009. Separate wet versus dry atmospheric deposition samples and wetland water samples were also taken in these years. In general, pesticides were detected in the monitored environmental media as mixtures with the frequency and concentrations detected being largest for pesticides that were applied on-site. Although the most commonly used herbicides in western Canadian agriculture were frequently present in the air in the regions where they are applied, they appeared infrequently and at low levels in the Canadian Subarctic, Arctic, and remote sites far from agricultural pesticide applications. Results also indicated that the concentrations of legacy pesticides such as lindane (γ-HCH) and its manufacturing by-product prior to 1971 (α-HCH) continued to decrease over time in the Canadian environment. Air concentrations of pesticides in agricultural regions, and subsequent wet and dry atmospheric deposition, contaminated surface water following periods of pesticide application. Dry deposition contributed 12–51% of the total deposition. Calculations were performed to predict wetland water column pesticide concentrations based on total atmospheric deposits alone. The estimated concentrations were closest to actual concentrations for MCPA and predictions were also reasonable for a range of other herbicides, but a source other than atmospheric deposition was clearly relevant to the detection of clopyralid in the wetland water-column. Individual herbicide concentrations did not exceed Canadian water quality guidelines for the protection of aquatic life.
Книги з теми "Depositions in wetlands":
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NATO Advanced Research Workshop on Effects of Acidic Deposition on Forests, Wetlands, and Agricultural Ecosystems (1985 Toronto, Ont.). Effects of atmospheric pollutants on forests, wetlands, and agricultural ecosystems. Berlin: Springer-Verlag, 1987.
Rodrigue, D. MR-06, Channel Armor gap crevasse: Summary data and graphics. Baton Rouge, La: Louisiana Department of Natural Resources, Coastal Restoration Division, Biological Monitoring Section, 2003.
United States. Congress. Senate. Committee on Environment and Public Works. Subcommittee on Clean Air, Wetlands, Private Property, and Nuclear Safety. Acid Deposition Control Act: Hearing before the Subcommittee on Clean Air, Wetlands, Private Property and Nuclear Safety of the Committee on Environment and Public Works, United States Senate, One Hundred Fifth Congress, second session, on S. 1097 ... October 6, 1998. Washington: U.S. G.P.O., 1999.
1957-, Lewis Lisa, Clark Lisa, National Science and Technology Center (U.S.), United States. Bureau of Land Management, United States Forest Service, United States. Natural Resources Conservation Service, and National Riparian Service Team (U.S.), eds. Riparian-wetland soils. Denver, CO: U.S. Bureau of Land Management, National Science and Technology Center, 2003.
1957-, Lewis Lisa, Clark Lisa, National Science and Technology Center (U.S.), United States. Bureau of Land Management., United States Forest Service, United States. Natural Resources Conservation Service., and National Riparian Service Team (U.S.), eds. Riparian-wetland soils. Denver, CO: U.S. Bureau of Land Management, National Science and Technology Center, 2003.
US GOVERNMENT. Acid Deposition Control Act: Hearing before the Subcommittee on Clean Air, Wetlands, Private Property and Nuclear Safety of the Committee on Environment ... on S. 1097 ... October 6, 1998 (S. hrg). For sale by the U.S. G.P.O., Supt. of Docs., Congressional Sales Office, 1999.
Lindberg, S. E., G. M. Lovett, and K.-J. Meiwes. "Deposition and Forest Canopy Interactions of Airborne Nitrate." In Effects of Atmospheric Pollutants on Forests, Wetlands and Agricultural Ecosystems, 117–30. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-70874-9_8.
Tomlinson, G. H. "Acid Deposition, Nurtrient Imbalance and Tree Decline: A Commentary." In Effects of Atmospheric Pollutants on Forests, Wetlands and Agricultural Ecosystems, 189–99. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-70874-9_13.
LeBlanc, D. C., D. J. Raynal, and E. H. White. "Dendroecological Analysis of Acidic Deposition Effects on Forest Productivity." In Effects of Atmospheric Pollutants on Forests, Wetlands and Agricultural Ecosystems, 291–306. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-70874-9_21.
Unsworth, M. H., and A. Crossley. "Consequences of Cloud Water Deposition on Vegetation at High Elevation." In Effects of Atmospheric Pollutants on Forests, Wetlands and Agricultural Ecosystems, 171–88. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-70874-9_12.
Lee, J. A., M. C. Press, S. Woodin, and P. Ferguson. "Responses to Acidic Deposition in Ombrotrophic Mires in the U.K." In Effects of Atmospheric Pollutants on Forests, Wetlands and Agricultural Ecosystems, 549–60. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-70874-9_39.
Evans, L. S., and K. F. Lewin. "Perspectives on Establishing the Relationship between Acidic Deposition and Vegetation Responses." In Effects of Atmospheric Pollutants on Forests, Wetlands and Agricultural Ecosystems, 611–18. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-70874-9_43.
Ferm, Martin, and Hans Hultberg. "Neutralisation of Sulphur Dioxide Deposition in a Coniferous Canopy." In Biogeochemical Investigations of Terrestrial, Freshwater, and Wetland Ecosystems across the Globe, 237–45. Dordrecht: Springer Netherlands, 2004. http://dx.doi.org/10.1007/978-94-007-0952-2_17.
Mansfield, T. A., M. E. Whitmore, P. C. Pande, and P. H. Freer-Smith. "Responses of Herbaceous and Woody Plants to the Dry Deposition of SO2 and NO2." In Effects of Atmospheric Pollutants on Forests, Wetlands and Agricultural Ecosystems, 131–44. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-70874-9_9.
Morgan, Mark D. "Modeling Excess Sulfur Deposition on Wetland Soils Using Stable Sulfur Isotopes." In Biogeochemical Monitoring in Small Catchments, 299–307. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0261-2_17.
Johnson, D. W. "A Discussion of the Changes in Soil Acidity due to Natural Processes and Acid Deposition." In Effects of Atmospheric Pollutants on Forests, Wetlands and Agricultural Ecosystems, 333–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-70874-9_24.
Тези доповідей конференцій з теми "Depositions in wetlands":
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Han, Xiao, and Ning Zhang. "Coastal Hydrodynamic and Sediment-Salinity Transport Simulations for Southwest Louisiana Using Measured Vegetation Data." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-51571.
Storm-surge flood is a major thread to the inhabitants and the health of the marshes in Southwest Louisiana. The floods caused direct damages to the area, but also indirectly caused excessive sedimentations in the water system, especially in Calcasieu Ship Channel which is a vital industrial water way connecting the City of Lake Charles to the Gulf. It is well known that coastal wetlands and marshes have significant impacts on the prevention and reduction of coastal floods. The wetland vegetation creates larger frictions to the flooding water and acts as the first line of defense against any storm surge floods. In this study, we center Calcasieu Ship Channel, and hydrodynamic and sediment transport simulations were conducted for Calcasieu Ship Channel and surrounding areas. The target area ranges from the city of Lake Charles as the north end and the Gulf of Mexico as the south end, and includes three connected water systems, Calcaiseu Lake, Prien Lake and Lake Charles. The entire Calcasieu Ship Channel running from north to south is included in the domain along with the Gulf Intracoastal Waterway (GIWW) in east and west directions. In authors’ previous study, only the area of south portion of the ship channel, Calcasieu Lake and its surrounding wetlands was simulated and studied. This study is a major upgrade to the model, which provides more complete understanding of the flow and sediment transport in the entire area, as well as the interactions among all water systems surrounding the ship channel. There are wetlands (two National Wild Life Refuges, one in the west and one in the east) surrounding Calcaiseu Lake, while there are various of vegetated and non-vegetated areas surrounding Prien Lake and Lake Charles. The standard 2-D depth averaged shallow water solver was utilized for the simulation of the flow phase and a standard Eulerian scalar transport equation was solved for the sediment and salinity phases. In the sediment phase, the sediment deposition and re-suspension effects are included, while in the salinity phase, the precipitation and evaporation are included. A realistic vegetation model was implemented to represent various types of vegetation coverage in the target area, and appropriate friction values were assigned to different non-vegetated areas. Measured and observed vegetation data were utilized. A coastal storm surge flood was simulated, and effects of vegetation on flood reduction and sediment distribution were investigated. The total flooded area, the flood speed, and the distribution of the flooding water and sediments were compared between vegetated and non-vegetated areas to show the differences between different types of surfaces.
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Foltz, William, and Ning Zhang. "Numerical Analysis of the Turbulent Flow Characteristics Around Submerged Permeable Breakwaters." In ASME 2018 5th Joint US-European Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/fedsm2018-83155.
A breakwater is a structure used to reduce the energy of waves. When used properly, they can protect coasts from being affected by waves. One such application is to lessen erosion along Louisiana’s coastlines, where wave action is strong and is the main source of the erosion. Additionally, the breakwater can change how sediments are transported, and allow for the deposition and accumulation of sediment at target areas. This research aims to give a numerical comparison of the effectiveness of three different breakwater designs, and reveal the turbulence characteristics downstream of the breakwaters. Three breakwaters are examined: a solid panel without any holes, another panel with one hole, and a third panel with three holes. These breakwaters are expected to be placed on the banks of various water bodies in coastal Louisiana, to protect the surrounding wetlands from coastal erosion and land losses. The designs aim to reduce the wave action from the water bodies, while the holes on them allow the sediments to pass through and deposit on the wetlands downstream. To run the simulations, the CFD software ANSYS FLUENT was used. The numerical results were compared to experimental data, and the good agreement proves the accuracy of the results. The effects of different wave patterns on the downstream turbulence were also analyzed and discussed in this study.
Звіти організацій з теми "Depositions in wetlands":
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Quantity and quality of urban storm runoff in the Irondequoit Creek basin near Rochester, New York; Part 2, Quality of storm runoff and atmospheric deposition, rainfall-runoff-quality modeling and potential of wetlands for sediment and nutrient retention. US Geological Survey, 1986. http://dx.doi.org/10.3133/wri854113.
