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Drainage Ditches (drainage + ditch)

Distribution by Scientific Domains
Life Sciences50%
Engineering35%

Selected Abstracts

Impact of Dredging on Phosphorus Transport in Agricultural Drainage Ditches of the Atlantic Coastal Plain,

JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2008
Francirose Shigaki
Abstract:, Drainage ditches can be a key conduit of phosphorus (P) between agricultural soils of the Atlantic Coastal Plain and local surface waters, including the Chesapeake Bay. This study sought to quantify the effect of a common ditch management practice, sediment dredging, on fate of P in drainage ditches. Sediments from two drainage ditches that had been monitored for seven years and had similar characteristics (flow, P loadings, sediment properties) were sampled (0-5 cm) after one of the ditches had been dredged, which removed fine textured sediments (clay = 41%) with high organic matter content (85 g/kg) and exposed coarse textured sediments (clay = 15%) with low organic matter content (2.2 g/kg). Sediments were subjected to a three-phase experiment (equilibrium, uptake, and release) in recirculating 10-m-long, 0.2-m-wide, and 5-cm-deep flumes to evaluate their role as sources and sinks of P. Under conditions of low initial P concentrations in flume water, sediments from the dredged ditch released 13 times less P to the water than did sediments from the ditch that had not been dredged, equivalent to 24 mg dissolved P. However, the sediments from the dredged ditch removed 19% less P (76 mg) from the flume water when it was spiked with dissolved P to approximate long-term runoff concentrations. Irradiation of sediments to destroy microorganisms revealed that biological processes accounted for up to 30% of P uptake in the coarse textured sediments of the dredged ditch and 18% in the fine textured sediments of the undredged ditch. Results indicate that dredging of coastal plain drainage ditches can potentially impact the P buffering capacity of ditches draining agricultural soils with a high potential for P runoff. [source]

Vegetated agricultural drainage ditches for the mitigation of pyrethroid-associated runoff

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2005
Erin R. Bennett
Abstract Drainage ditches are indispensable components of the agricultural production landscape. A benefit of these ditches is contaminant mitigation of agricultural storm runoff. This study determined bifenthrin and lambda-cyhalothrin (two pyrethroid insecticides) partitioning and retention in ditch water, sediment, and plant material as well as estimated necessary ditch length required for effective mitigation. A controlled-release runoff simulation was conducted on a 650-m vegetated drainage ditch in the Mississippi Delta, USA. Bifenthrin and lambda-cyhalothrin were released into the ditch in a water-sediment slurry. Samples of water, sediment, and plants were collected and analyzed for pyrethroid concentrations. Three hours following runoff initiation, inlet bifenthrin and lambda-cyhalothrin water concentrations ranged from 666 and 374 ,g/L, respectively, to 7.24 and 5.23 ,g/L at 200 m downstream. No chemical residues were detected at the 400-m sampling site. A similar trend was observed throughout the first 7 d of the study where water concentrations were elevated at the front end of the ditch (0,25 m) and greatly reduced by the 400-m sampling site. Regression formulas predicted that bifenthrin and lambda-cyhalothrin concentrations in ditch water were reduced to 0.1% of the initial value within 280 m. Mass balance calculations determined that ditch plants were the major sink and/or sorption site responsible for the rapid aqueous pyrethroid dissipation. By incorporating vegetated drainage ditches into a watershed management program, agriculture can continue to decrease potential non-point source threats to downstream aquatic receiving systems. Overall results of this study illustrate that aquatic macrophytes play an important role in the retention and distribution of pyrethroids in vegetated agricultural drainage ditches. [source]

Impact of Dredging on Phosphorus Transport in Agricultural Drainage Ditches of the Atlantic Coastal Plain,

JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2008
Francirose Shigaki
Abstract:, Drainage ditches can be a key conduit of phosphorus (P) between agricultural soils of the Atlantic Coastal Plain and local surface waters, including the Chesapeake Bay. This study sought to quantify the effect of a common ditch management practice, sediment dredging, on fate of P in drainage ditches. Sediments from two drainage ditches that had been monitored for seven years and had similar characteristics (flow, P loadings, sediment properties) were sampled (0-5 cm) after one of the ditches had been dredged, which removed fine textured sediments (clay = 41%) with high organic matter content (85 g/kg) and exposed coarse textured sediments (clay = 15%) with low organic matter content (2.2 g/kg). Sediments were subjected to a three-phase experiment (equilibrium, uptake, and release) in recirculating 10-m-long, 0.2-m-wide, and 5-cm-deep flumes to evaluate their role as sources and sinks of P. Under conditions of low initial P concentrations in flume water, sediments from the dredged ditch released 13 times less P to the water than did sediments from the ditch that had not been dredged, equivalent to 24 mg dissolved P. However, the sediments from the dredged ditch removed 19% less P (76 mg) from the flume water when it was spiked with dissolved P to approximate long-term runoff concentrations. Irradiation of sediments to destroy microorganisms revealed that biological processes accounted for up to 30% of P uptake in the coarse textured sediments of the dredged ditch and 18% in the fine textured sediments of the undredged ditch. Results indicate that dredging of coastal plain drainage ditches can potentially impact the P buffering capacity of ditches draining agricultural soils with a high potential for P runoff. [source]

Vegetated agricultural drainage ditches for the mitigation of pyrethroid-associated runoff

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2005
Erin R. Bennett
Abstract Drainage ditches are indispensable components of the agricultural production landscape. A benefit of these ditches is contaminant mitigation of agricultural storm runoff. This study determined bifenthrin and lambda-cyhalothrin (two pyrethroid insecticides) partitioning and retention in ditch water, sediment, and plant material as well as estimated necessary ditch length required for effective mitigation. A controlled-release runoff simulation was conducted on a 650-m vegetated drainage ditch in the Mississippi Delta, USA. Bifenthrin and lambda-cyhalothrin were released into the ditch in a water-sediment slurry. Samples of water, sediment, and plants were collected and analyzed for pyrethroid concentrations. Three hours following runoff initiation, inlet bifenthrin and lambda-cyhalothrin water concentrations ranged from 666 and 374 ,g/L, respectively, to 7.24 and 5.23 ,g/L at 200 m downstream. No chemical residues were detected at the 400-m sampling site. A similar trend was observed throughout the first 7 d of the study where water concentrations were elevated at the front end of the ditch (0,25 m) and greatly reduced by the 400-m sampling site. Regression formulas predicted that bifenthrin and lambda-cyhalothrin concentrations in ditch water were reduced to 0.1% of the initial value within 280 m. Mass balance calculations determined that ditch plants were the major sink and/or sorption site responsible for the rapid aqueous pyrethroid dissipation. By incorporating vegetated drainage ditches into a watershed management program, agriculture can continue to decrease potential non-point source threats to downstream aquatic receiving systems. Overall results of this study illustrate that aquatic macrophytes play an important role in the retention and distribution of pyrethroids in vegetated agricultural drainage ditches. [source]

The dispersal and deposition of hydrochorous plant seeds in drainage ditches

FRESHWATER BIOLOGY, Issue 10 2010
HESTER SOOMERS
Summary 1. Surface water is an important dispersal vector for wetland plant species. However, most previous studies on hydrochory (i.e. water dispersal) have focused on ecosystems with relatively rapid water flow. Therefore, there is a need to study such dispersal in slow-flowing or stagnant waterbodies, such as drainage ditches, which might act as dispersal corridors between habitat patches. 2. To gain insight into the mechanisms by which seeds are transported in drainage ditches, the effect of the velocity of wind and water on the rate of transport of floating seeds of three wetland species (Carex pseudocyperus L., Iris pseudacorus L. and Sparganium erectum L.) was investigated. Furthermore, in release and retrace experiments with painted C. pseudocyperus seeds, a number of factors potentially determining the probability of seed deposition were investigated. 3. Net wind speed was found to be the main factor determining the rate at which seeds are transported in drainage ditches. No relation between water flow at middepth in the ditches and seed transport was found. Wind speed and flow at the water surface were positively related. The effect of wind speed on the rate of transport of floating seeds was greater for S. erectum seeds, because a greater ratio of their volume protrudes from the water, than for C. pseudocyperus and I. pseudacorus seeds. 4. The principal factors that determine seed deposition were aquatic plant cover, ditch slope and indentations in the ditch bank. Seeds changed direction if the wind direction changed, or if there was a bend in the ditch. The final pattern of deposition was related to mean net wind speed. Mean transport distance after 2 days varied between 34 and 451 m. 5. Unlike in rivers, seed transport in ditches was determined by wind speed and direction, enabling multidirectional seed dispersal. We conclude that in slow-flowing waters, wind is a more important driver for hydrochorous seed transport than the flow of water. This sheds a new light on hydrochory and has important consequences for the management of otherwise fragmented wetland remnants. [source]

Characterization of surface storage and runoff patterns following peatland restoration, Quebec, Canada

HYDROLOGICAL PROCESSES, Issue 18 2006
M. A. Shantz
Abstract Blocking drainage ditches and creating bunds to limit surface water losses are important for restoring abandoned peat-extraction sites in North America. However, these runoff control techniques have not been well characterized, particularly during the snowmelt period. Therefore, patterns of runoff timing and magnitude were evaluated in a peatland (Bois-des-Bel, Quebec, Canada) undergoing restoration (restored site), in comparison with an unrestored section of the same peatland (unrestored site). Snowmelt dominated runoff, representing over 79% of the April to August runoff for both sites in 2001. Low (25,35 cm) bunds constructed on the restored site detained water for much of the melt period, but some water loss occurred where bunds were breached. Overland flow and surface ponding were prevalent at the restored site, but were not evident at the unrestored site. At the restored site, the presence of bunds and frozen, saturated (thus impermeable) ground contributed to differences in snowmelt runoff patterns relative to the unrestored site. In the post-snowmelt period (May,August 2001 and 2002), restored site runoff was reduced to 25% of that lost at the unrestored site. Both hydrometric and chemical hydrograph separation analysis using electrical conductivity indicated that blocked ditches restricted water losses from much of the restored site during the summer months, when the bunds had little effect on runoff. However, discharge peaks were greater at the restored site relative to the unrestored site and generally occurred more quickly following rainfall, because of the wetter antecedent conditions. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Impact of Dredging on Phosphorus Transport in Agricultural Drainage Ditches of the Atlantic Coastal Plain,

JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2008
Francirose Shigaki
Abstract:, Drainage ditches can be a key conduit of phosphorus (P) between agricultural soils of the Atlantic Coastal Plain and local surface waters, including the Chesapeake Bay. This study sought to quantify the effect of a common ditch management practice, sediment dredging, on fate of P in drainage ditches. Sediments from two drainage ditches that had been monitored for seven years and had similar characteristics (flow, P loadings, sediment properties) were sampled (0-5 cm) after one of the ditches had been dredged, which removed fine textured sediments (clay = 41%) with high organic matter content (85 g/kg) and exposed coarse textured sediments (clay = 15%) with low organic matter content (2.2 g/kg). Sediments were subjected to a three-phase experiment (equilibrium, uptake, and release) in recirculating 10-m-long, 0.2-m-wide, and 5-cm-deep flumes to evaluate their role as sources and sinks of P. Under conditions of low initial P concentrations in flume water, sediments from the dredged ditch released 13 times less P to the water than did sediments from the ditch that had not been dredged, equivalent to 24 mg dissolved P. However, the sediments from the dredged ditch removed 19% less P (76 mg) from the flume water when it was spiked with dissolved P to approximate long-term runoff concentrations. Irradiation of sediments to destroy microorganisms revealed that biological processes accounted for up to 30% of P uptake in the coarse textured sediments of the dredged ditch and 18% in the fine textured sediments of the undredged ditch. Results indicate that dredging of coastal plain drainage ditches can potentially impact the P buffering capacity of ditches draining agricultural soils with a high potential for P runoff. [source]

Utilization of common ditch vegetation in the reduction of fipronil and its sulfone metabolite

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 12 2008
Robert Kröger
Abstract BACKGROUND: Fipronil, a phenylpyrazole insecticide, and its oxidative sulfone metabolite are two potential pollutants from treated rice and cotton production. A consequence of these pollutants occurring in surface runoff is degradation of downstream aquatic ecosystems. Utilization of primary intercept drainage ditches as management practices to reduce fipronil concentrations and loads has not been examined. This study used ditch mesocosms planted with monospecific stands of common emergent wetland vegetation to determine if certain plant species were more proficient in fipronil mitigation. RESULTS: Three replicates of four plant species were compared against a non-vegetated control to determine differences in water column outflow concentrations (µg L,1) and loads (µg). There were no significant differences between vegetated and control treatments in outflow concentrations (F = 0.35, P = 0.836) and loads (F = 0.35, P = 0.836). The range of fipronil reduction was 28,45% for both concentration and load. Unlike fipronil, fipronil sulfone concentrations and load increased by 96,328%. CONCLUSION: The increase in fipronil sulfone was hypothesized as a direct consequence of oxidation of fipronil within each mesocosm. The type of ditch vegetation had no effect on fipronil reduction. Future research needs to examine initial concentrations and hydraulic retention times to examine potential changes in reduction capacities. Copyright © 2008 Society of Chemical Industry [source]

The impact of site conditions and seed dispersal on restoration success in alluvial meadows

APPLIED VEGETATION SCIENCE, Issue 1 2003
Tobias W. Donath
Wisskirchen & Haeupler (1998) Abstract. We studied the restoration success of flood plain meadows in the northern Upper Rhine valley, where between 1988 and 1992, 35 ha of arable land was converted into grassland and subsequently managed for nature conservation. Remnant populations of typical alluvial meadow species were found in old meadows and along drainage ditches that dissect the whole area. We analysed the site conditions and phytosociological relevés in old and new meadows. Small differences in site parameters between old and new meadows contrasted with a clear floristic differentiation between the two meadow types. The vegetation of old meadows was much more differentiated along prevailing environmental gradients than the vegetation of new meadows. Despite the favourable site conditions for the re-establishment of species-rich meadows on the former arable land, restoration success was limited to the vicinity of remnant stands. In contrast to old meadows, indicator species of new grassland were still typical species of regularly disturbed ruderal and arable habitats, often capable of building up a persistent seed bank. The precise mapping of 23 target species revealed that even wind dispersal predominantly leads to re-establishment in the close circumference of parent plants. We found no indication that regular flooding, hay-making and autumnal grazing had an impact on recolonization of newly created grassland. Even under favourable conditions for the re-establishment of target species, restoration success in alluvial meadows proved to be strongly dispersal limited. We discuss the implications of our findings for future restoration management in grasslands. [source]