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Sample records for agricultural drainage ditches

  1. Vertical distribution of phosphorus in agricultural drainage ditch soils.

    Science.gov (United States)

    Vaughan, Robert E; Needelman, Brian A; Kleinman, Peter J A; Allen, Arthur L

    2007-01-01

    Pedological processes such as gleization and organic matter accumulation may affect the vertical distribution of P within agricultural drainage ditch soils. The objective of this study was to assess the vertical distribution of P as a function of horizonation in ditch soils at the University of Maryland Eastern Shore Research Farm in Princess Anne, Maryland. Twenty-one profiles were sampled from 10 agricultural ditches ranging in length from 225 to 550 m. Horizon samples were analyzed for total P; water-extractable P; Mehlich-3 P; acid ammonium oxalate-extractable P, Fe, and Al (P ox, Fe ox, Al ox); pH; and organic C (n = 126). Total P ranged from 27 to 4882 mg kg(-1), P ox from 4 to 4631 mg kg(-1), Mehlich-3 P from 2 to 401 mg kg(-1), and water-extractable P from 0 to 17 mg kg(-1). Soil-forming processes that result in differences between horizons had a strong relationship with various P fractions and P sorption capacity. Fibric organic horizons at the ditch soil surface had the greatest mean P ox, Fe ox, and Al ox concentrations of any horizon class. Gleyed A horizons had a mean Fe ox concentrations 2.6 times lower than dark A horizons and were significantly lower in total P and P ox. Variation in P due to organic matter accumulation and gleization provide critical insight into short- and long-term dynamics of P in ditch soils and should be accounted for when applying ditch management practices.

  2. Development of a multimetric index based on macroinvertebrates for drainage ditch networks in agricultural areas.

    NARCIS (Netherlands)

    Verdonschot, R.C.M.; Keizer-Vlek, H.E.; Verdonschot, P.F.M.

    2012-01-01

    Drainage ditches are a prominent feature of many intensively managed agricultural areas. These small, shallow, line-shaped waterbodies could harbor a rich macroinvertebrate community, resembling that of natural small lentic ecosystems. Despite their high biodiversity potential, many ditch ecosystems

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

    Science.gov (United States)

    Bennett, Erin R; Moore, Matthew T; Cooper, Charles M; Smith, Sammie; Shields, F Douglas; Drouillard, Ken G; Schulz, Ralf

    2005-09-01

    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 microg/L, respectively, to 7.24 and 5.23 microg/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.

  4. Nitrate removal from agricultural drainage ditch sediments with amendments of organic carbon: Potential for an innovative best management practice

    Science.gov (United States)

    Faust, Derek R.; Kröger, Robert; Miranda, Leandro E.; Rush, Scott A.

    2016-01-01

    Agricultural fertilizer applications have resulted in loading of nutrients to agricultural drainage ditches in the Lower Mississippi Alluvial Valley. The purpose of this study was to determine effects of dissolved organic carbon (DOC) and particulate organic carbon (POC) amendments on nitrate-nitrogen (NO3−-N) removal from overlying water, pore water, and sediment of an agricultural drainage ditch. Two experiments were conducted. In experiment 1, control (i.e., no amendment), DOC, and POC treatments were applied in laboratory microcosms for time intervals of 3, 7, 14, and 28 days. In experiment 2, control, DOC, and POC treatments were applied in microcosms at C/N ratios of 5:1, 10:1, 15:1, and 20:1. There were statistically significant effects of organic carbon amendments in experiment 1 (F2,71 = 27.1, P < 0.001) and experiment 2 (F2,53 = 39.1, P < 0.001), time (F1,71 = 14.5, P < 0.001) in experiment 1, and C/N ratio (F1,53 = 36.5, P < 0.001) in experiment 2. NO3−-N removal varied from 60 to 100 % in overlying water among all treatments. The lowest NO3−-N removals in experiment 1 were observed in the control at 14 and 28 days, which were significantly less than in DOC and POC 14- and 28-day treatments. In experiment 2, significantly less NO3−-N was removed in overlying water of the control compared to DOC and POC treatments at all C/N ratios. Amendments of DOC and POC made to drainage ditch sediment: (1) increased NO3−-N removal, especially over longer time intervals (14 to 28 days); (2) increased NO3−-N removal, regardless of C/N ratio; and (3) NO3−-N removal was best at a 5:1 C/N ratio. This study provides support for continued investigation on the use of organic carbon amendments as a best management practice for NO3−-N removal in agricultural drainage ditches.

  5. Sorption of selected pesticides on soils, sediment and straw from a constructed agricultural drainage ditch or pond.

    Science.gov (United States)

    Vallée, Romain; Dousset, Sylvie; Billet, David; Benoit, Marc

    2014-04-01

    Buffer zones such as ponds and ditches are used to reduce field-scale losses of pesticides from subsurface drainage waters to surface waters. The objective of this study was to assess the efficiency of these buffer zones, in particular constructed wetlands, focusing specifically on sorption processes. We modelled the sorption processes of three herbicides [2-methyl-4-chlorophenoxyacetic acid (2,4-MCPA), isoproturon and napropamide] and three fungicides (boscalid, prochloraz and tebuconazole) on four substrates (two soils, sediment and straw) commonly found in a pond and ditch in Lorraine (France). A wide range of Freundlich coefficient (K fads) values was obtained, from 0.74 to 442.63 mg(1 - n) L (n) kg(-1), and the corresponding K foc values ranged from 56 to 3,725 mg(1 - n) L (n) kg(-1). Based on potential retention, the substrates may be classified as straw > sediments > soils. These results show the importance of organic carbon content and nature in the process of sorption. Similarly, the studied pesticides could be classified according to their adsorption capacity as follows: prochloraz > tebuconazole-boscalid > napropamide > MCPA-isoproturon. This classification is strongly influenced by the physico-chemical properties of pesticides, especially solubility and K oc. Straw exhibited the largest quantity of non-desorbable pesticide residues, from 12.1 to 224.2 mg/L for all pesticides. The presence of plants could increase soil-sediment sorption capacity. Thus, establishment and maintenance of plants and straw filters should be promoted to optimise sorption processes and the efficiency of ponds and ditches in reducing surface water pollution.

  6. A transition to white LED increases ecological impacts of nocturnal illumination on aquatic primary producers in a lowland agricultural drainage ditch.

    Science.gov (United States)

    Grubisic, Maja; van Grunsven, Roy H A; Manfrin, Alessandro; Monaghan, Michael T; Hölker, Franz

    2018-05-14

    The increasing use of artificial light at night (ALAN) has led to exposure of freshwater ecosystems to light pollution worldwide. Simultaneously, the spectral composition of nocturnal illumination is changing, following the current shift in outdoor lighting technologies from traditional light sources to light emitting diodes (LED). LEDs emit broad-spectrum white light, with a significant amount of photosynthetically active radiation, and typically a high content of blue light that regulates circadian rhythms in many organisms. While effects of the shift to LED have been investigated in nocturnal animals, its impact on primary producers is unknown. We performed three field experiments in a lowland agricultural drainage ditch to assess the impacts of a transition from high-pressure sodium (HPS) to white LED illumination (color temperature 4000 K) on primary producers in periphyton. In all experiments, we compared biomass and pigment composition of periphyton grown under a natural light regime to that of periphyton exposed to nocturnal HPS or, consecutively, LED light of intensities commonly found in urban waters (approximately 20 lux). Periphyton was collected in time series (1-13 weeks). We found no effect of HPS light on periphyton biomass; however, following a shift to LED the biomass decreased up to 62%. Neither light source had a substantial effect on pigment composition. The contrasting effects of the two light sources on biomass may be explained by differences in their spectral composition, and in particular the blue content. Our results suggest that spectral composition of the light source plays a role in determining the impacts of ALAN on periphyton and that the ongoing transition to LED may increase the ecological impacts of artificial lighting on aquatic primary producers. Reduced biomass in the base of the food web can impact ecosystem functions such as productivity and food supply for higher trophic levels in nocturnally-lit ecosystems. Copyright

  7. Dredging effects on selected nutrient concentrations and ecoenzymatic activity in two drainage ditch sediments in the lower Mississippi River Valley

    Directory of Open Access Journals (Sweden)

    Matt Moore

    2017-09-01

    Full Text Available Agricultural drainage ditches are conduits between production acreage and receiving aquatic systems. Often overlooked for their mitigation capabilities, agricultural drainage ditches provide an important role for nutrient transformation via microbial metabolism. Variations in ecoenzyme activities have been used to elucidate microbial metabolism and resource demand of microbial communities to better understand the relationship between altered nutrient ratios and microbial activity in aquatic ecosystems. Two agricultural drainage ditches, one in the northeast portion of the Arkansas Delta and the other in the lower Mississippi Delta, were monitored for a year. Sediment samples were collected prior to each ditch being dredged (cleaned, and subsequent post-dredging samples occurred as soon as access was available. Seasonal samples were then collected throughout a year to examine effects of dredging on selected nutrient concentrations and ecoenzymatic activity recovery in drainage ditch sediments. Phosphorus concentrations in sediments after dredging decreased 33–66%, depending on ditch and phosphorus extraction methodology. Additionally, ecoenzymatic activity was significantly decreased in most sediment samples after dredging. Fluorescein diacetate hydrolysis activity, an estimate of total microbial activity, decreased 56–67% after dredging in one of the two ditches. Many sample sites also had significant phosphorus and ecoenzymatic activity differences between the post-dredge samples and the year-long follow-up samples. Results indicate microbial metabolism in dredged drainage ditches may take up to a year or more to recover to pre-dredged levels. Likewise, while sediment nutrient concentrations may be decreased through dredging and removal, runoff and erosion events over time tend to quickly replenish nutrient concentrations in replaced sediments. Understanding nutrient dynamics and microbial metabolism within agricultural drainage ditches is

  8. The role of emergent vegetation in structuring aquatic insect communities in peatland drainage ditches

    NARCIS (Netherlands)

    Whatley, M.H.; van Loon, E.E.; Vonk, J.A.; van der Geest, H.G.; Admiraal, W.

    2014-01-01

    Availability of macrophyte habitat is recognized as an important driver of aquatic insect communities in peatland drainage ditches; however, eutrophication can lead to the decline of submerged vegetation. While emergent vegetation is able to persist in eutrophicated ditches, vegetation removal,

  9. Exploring Agricultural Drainage's Influence on Wetland and ...

    Science.gov (United States)

    Artificial agricultural drainage (i.e. surface ditches or subsurface tile) is an important agricultural management tool. Artificial drainage allows for timely fieldwork and adequate root aeration, resulting in greater crop yields for farmers. This practice is widespread throughout many regions of the United States and the network of artificial drainage is especially extensive in flat, poorly-drained regions like the glaciated Midwest. While beneficial for crop yields, agricultural drains often empty into streams within the natural drainage system. The increased network connectivity may lead to greater contributing area for watersheds, altered hydrology and increased conveyance of pollutants into natural water bodies. While studies and models at broader scales have implicated artificial drainage as an important driver of hydrological shifts and eutrophication, the actual spatial extent of artificial drainage is poorly known. Consequently, metrics of wetland and watershed connectivity within agricultural regions often fail to explicitly include artificial drainage. We use recent agricultural census data, soil drainage data, and land cover data to create estimates of potential agricultural drainage across the United States. We estimate that agricultural drainage in the US is greater than 31 million hectares and is concentrated in the upper Midwest Corn Belt, covering greater than 50% of available land for 114 counties. Estimated drainage values for numerous countie

  10. Agricultural Drainage Well Intakes

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Locations of surface intakes for registered agriculture drainage wells according to the database maintained by IDALS. Surface intakes were located from their...

  11. Ditches and Drainage Structures, Culverts - cross drains were collected using a GPS for drainage basin project. Ditches are planned for the future., Published in 2005, 1:2400 (1in=200ft) scale, Effingham County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Ditches and Drainage Structures dataset current as of 2005. Culverts - cross drains were collected using a GPS for drainage basin project. Ditches are planned for...

  12. Agricultural drainage water quality

    International Nuclear Information System (INIS)

    Madani, A.; Gordon, R.

    2002-01-01

    'Full text:' Agricultural drainage systems have been identified as potential contributors of non-point source pollution. Two of the major concerns have been with nitrate-nitrogen (NO3 - -N) concentrations and bacteria levels exceeding the Maximum Acceptable Concentration in drainage water. Heightened public awareness of environmental issues has led to greater pressure to maintain the environmental quality of water systems. In an ongoing field study, three experiment sites, each with own soil properties and characteristics, are divided into drainage plots and being monitored for NO3 - -N and fecal coliforms contamination. The first site is being used to determine the impact of the rate of manure application on subsurface drainage water quality. The second site is being used to determine the difference between hog manure and inorganic fertilizer in relation to fecal coliforms and NO3-N leaching losses under a carrot rotation system. The third site examines the effect of timing of manure application on water quality, and is the only site equipped with a surface drainage system, as well as a subsurface drainage system. Each of the drains from these fields lead to heated outflow buildings to allow for year-round measurements of flow rates and water samples. Tipping buckets wired to data-loggers record the outflow from each outlet pipe on an hourly basis. Water samples, collected from the flowing drains, are analyzed for NO3 - -N concentrations using the colorimetric method, and fecal coliforms using the Most Probable Number (MPN) method. Based on this information, we will be able better positioned to assess agricultural impacts on water resources which will help towards the development on industry accepted farming practices. (author)

  13. Vegetative and structural characteristics of agricultural drainages in the Mississippi Delta landscapes

    International Nuclear Information System (INIS)

    Bouldin, J.L.; Farris, J.L.; Moore, M.T.; Cooper, C.M.

    2004-01-01

    Agricultural drainage ditches in the Mississippi Alluvial Delta landscape vary from edge-of-field waterways to sizeable drainages. Ditch attributes vary with size, location and maintenance and may aid in mitigation of contaminants from agricultural fields. The goal of this study was to better understand how vegetative characteristics affect water quality in conveyance structures in the context of ditch class and surrounding land use. Characterization of 36 agricultural ditches included presence of riparian buffer strips, water depth, surrounding land use, vegetative cover, and associated aqueous physicochemical parameters. Vegetation was assessed quantitatively, obtaining stem counts in a sub-sample of ditch sites, using random quadrat method. Physical features varied with ditch size and vegetative diversity was higher in larger structures. Polygonum sp. was the dominant bed vegetation and was ubiquitous among site sizes. Macrophytes varied from aquatic to upland species, and included Leersia sp. and upland grasses (Poaceae family) in all drainage size classes. Percent cover of bed and bank varied from 0 to 100% and 70 to 100%, respectively, and highest nutrient values were measured in sites with no buffer strips. These conveyance structures and surrounding buffer zones are being ranked for their ability to reduce excess nutrients, suspended solids, and pesticides associated with runoff. - Capsule: Vegetated buffer areas provide effective mitigation for non-point source pollution from agriculture

  14. Decreasing nitrate-N loads to coastal ecosystems with innovative drainage management strategies in agricultural landscapes: An experimental approach

    Science.gov (United States)

    Controlled drainage in agricultural ditches contributes to a drainage management strategy with potential environmental and production benefits. Innovative drainage strategies including spatially orientated low-grade weirs show promise to significantly improve nutrient (e.g. nitrate-N) reductions by...

  15. The role of drainage ditches in greenhouse gas emissions and surface leaching losses from a cutaway peatland cultivated with a perennial bioenergy crop

    Energy Technology Data Exchange (ETDEWEB)

    Hyvonen, N.P.; Huttunen, J.T.; Shurpali, N.J.; Lind, S.E.; Marushchak, M.E.; Martikainen, P.J. [University of Eastern Finland, Kuopio (Finland). Dept. of Environmental Science], E-mail: niina.hyvonen@uef.fi; Heitto, L. [Environmental Research of Savo-Karjala Ltd, Kuopio (Finland)

    2013-06-01

    We studied greenhouse gas (GHG) emissions from drainage ditches and leaching losses in a boreal cutaway peatland cultivated with reed canary grass (Phalaris arundinacea) for bioenergy. The objectives of the study were to assess to what extent GHG emissions from drainage ditches and leaching of carbon and nutrients via surface drainage contribute to the total losses of carbon and nitrogen from the site. The emissions of CH{sub 4}, N{sub 2}O and CO{sub 2} were measured with static chamber methods for three years and leaching losses for seven years. On average, the drainage ditches (covering 6% of the study site area) released 10% of the total CH{sub 4} emission (0.33 g m{sup -2} a{sup -1}), and 1% and 5% of the total N{sub 2}O and CO{sub 2} emissions, respectively. Leaching of total nitrogen and phosphorous were 0.31 and 0.03 g m{sup -2} a{sup -1}, respectively. Leaching values were lower than those reported for agricultural catchments in general. (orig.)

  16. A steady state solution for ditch drainage problem with special reference to seepage face and unsaturated zone flow contribution: Derivation of a new drainage spacing eqaution

    Science.gov (United States)

    Yousfi, Ammar; Mechergui, Mohammed

    2016-04-01

    The seepage face is an important feature of the drainage process when recharge occurs to a permeable region with lateral outlets. Examples of the formation of a seepage face above the downstream water level include agricultural land drained by ditches. Flow problem to these drains has been investigated extensively by many researchers (e.g. Rubin, 1968; Hornberger et al. 1969; Verma and Brutsaert, 1970; Gureghian and Youngs, 1975; Vauclin et al., 1975; Skaggs and Tang, 1976; Youngs, 1990; Gureghian, 1981; Dere, 2000; Rushton and Youngs, 2010; Youngs, 2012; Castro-Orgaz et al., 2012) and may be tackled either using variably saturated flow models, or the complete 2-D solution of Laplace equation, or using the Dupuit-Forchheimer approximation; the most widely accepted methods to obtain analytical solutions for unconfined drainage problems. However, the investigation reported by Clement et al. (1996) suggest that accounting for the seepage face alone, as in the fully saturated flow model, does not improve the discharge estimate because of disregarding flow the unsaturated zone flow contribution. This assumption can induce errors in the location of the water table surface and results in an underestimation of the seepage face and the net discharge (e.g. Skaggs and Tang, 1976; Vauclin et al., 1979; Clement et al., 1996). The importance of the flow in the unsaturated zone has been highlighted by many authors on the basis of laboratory experiments and/or numerical experimentations (e.g. Rubin, 1968; Verma and Brutsaert, 1970; Todsen, 1973; Vauclin et al., 1979; Ahmad et al., 1993; Anguela, 2004; Luthin and Day, 1955; Shamsai and Narasimhan, 1991; Wise et al., 1994; Clement et al., 1996; Boufadel et al., 1999; Romano et al., 1999; Kao et al., 2001; Kao, 2002). These studies demonstrate the failure of fully saturated flow models and suggested that the error made when using these models not only depends on soil properties but also on the infiltration rate as reported by Kao et

  17. Contrasting nutrient mitigation and denitrification potential of agricultural drainage environments with different emergent aquatic macrophytes.

    Science.gov (United States)

    Remediation of excess nitrogen (N) in agricultural runoff can be enhanced by establishing wetland vegetation but the role of denitrification in N removal is not well understood in drainage ditches. We quantified differences in N retention during experimental runoff events followed by stagnant period...

  18. Determinants of Nitrous Oxide Emission from Agricultural Drainage Waters

    International Nuclear Information System (INIS)

    Reay, D. S.; Edwards, A. C.; Smith, K. A.

    2004-01-01

    Emissions of the powerful greenhouse gas nitrous oxide (N 2 O) from agricultural drainage waters are poorly quantified and its determinants are not fully understood. Nitrous oxide formation in agricultural soils is known to increase in response to N fertiliser application, but the response of N 2 O in field drainage waters is unknown. This investigation combined an intensive study of the direct flux of N 2 O from the surface of a fertilised barley field with measurement of dissolved N 2 O and nitrate (NO 3 ) concentrations in the same field's drainage waters. Dissolved N 2 O in drainage waters showed a clear response to field N fertilisation, following an identical pattern to direct N 2 O flux from the field surface. The range in N 2 O concentrations between individual field drains sampled on the same day was large, indicating considerable spatial variability exists at the farm scale. A consistent pattern of very rapid outgassing of the dissolved N 2 O in open drainage ditches was accentuated at a weir, where increased turbulence led to a clear drop in dissolved N 2 O concentration. This study underlines the need for carefully planned sampling campaigns wherever whole farm or catchment N 2 O emission budgets are attempted. It adds weight to the argument for the downward revision of the IPCC emission factor (EF 5 -g) for NO 3 in drainage waters

  19. Determinants of nitrous oxide emission from agricultural drainage waters

    International Nuclear Information System (INIS)

    Reay, D. S.; Edwards, A. C.; Smith, K. A.

    2005-01-01

    Emissions of the powerful greenhouse gas nitrous oxide (N 2 O) from agricultural drainage waters are poorly quantified and its determinants are not fully understood. Nitrous oxide formation in agricultural soils is known to increase in response to N fertiliser application, but the response of N 2 O in field drainage waters is unknown. This investigation combined an intensive study of the direct flux of N 2 O from the surface of a fertilised barley field with measurement of dissolved N 2 O and nitrate (NO 3 ) concentrations in the same field's drainage waters. Dissolved N 2 O in drainage waters showed a clear response to field N fertilisation, following an identical pattern to direct N 2 O flux from the field surface. The range in N 2 O concentrations between individual field drains sampled on the same day was large, indicating considerable spatial variability exists at the farm scale. A consistent pattern of very rapid outgassing of the dissolved N 2 O in open drainage ditches was accentuated at a weir, where increased turbulence led to a clear drop in dissolved N 2 O concentration. This study underlines the need for carefully planned sampling campaigns wherever whole farm or catchment N 2 O emission budgets are attempted. It adds weight to the argument for the downward revision of the IPCC emission factor (EF 5 -g) for NO 3 in drainage waters

  20. Macrophyte loss drives decadal change in benthic invertebrates in peatland drainage ditches

    NARCIS (Netherlands)

    Whatley, M.H.; van Loon, E.; van Dam, H.; Vonk, J.A.; van der Geest, H.G.; Admiraal, W.

    2014-01-01

    1. Agricultural peatlands and their associated drainage systems are often highly managed and exposed to anthropogenic pressures, such as eutrophication and stable water tables, maintained via drainage during periods of high rainfall and inlet of, alkaline-rich, waters during dry periods. These

  1. Comparing two surface flow wetlands for removal of nutrients in agricultural drainage water

    DEFF Research Database (Denmark)

    Hoffmann, Carl Christian; Kjærgaard, Charlotte; Levesen, Bo

    In Denmark there is a growing interest for using constructed wetlands as a mean for removal of nutrients from agricultural run-off, such as drainage ditches and tile drainage systems. We have studied two surface flow constructed wetlands from district Vejle, Jutland, Denmark. The Vicarage Wetland.......020 mg P and unfiltered TP decreases with 75 % to 0.040 mg P l-1. The results from this study seem to indicate that constructed surface flow wetlands are able to remove nitrogen and retain phosphorus from agricultural drainage run-off although the nutrient concentrations are much lower as compared...

  2. Using geomorphological variables to predict the spatial distribution of plant species in agricultural drainage networks.

    Science.gov (United States)

    Rudi, Gabrielle; Bailly, Jean-Stéphane; Vinatier, Fabrice

    2018-01-01

    To optimize ecosystem services provided by agricultural drainage networks (ditches) in headwater catchments, we need to manage the spatial distribution of plant species living in these networks. Geomorphological variables have been shown to be important predictors of plant distribution in other ecosystems because they control the water regime, the sediment deposition rates and the sun exposure in the ditches. Whether such variables may be used to predict plant distribution in agricultural drainage networks is unknown. We collected presence and absence data for 10 herbaceous plant species in a subset of a network of drainage ditches (35 km long) within a Mediterranean agricultural catchment. We simulated their spatial distribution with GLM and Maxent model using geomorphological variables and distance to natural lands and roads. Models were validated using k-fold cross-validation. We then compared the mean Area Under the Curve (AUC) values obtained for each model and other metrics issued from the confusion matrices between observed and predicted variables. Based on the results of all metrics, the models were efficient at predicting the distribution of seven species out of ten, confirming the relevance of geomorphological variables and distance to natural lands and roads to explain the occurrence of plant species in this Mediterranean catchment. In particular, the importance of the landscape geomorphological variables, ie the importance of the geomorphological features encompassing a broad environment around the ditch, has been highlighted. This suggests that agro-ecological measures for managing ecosystem services provided by ditch plants should focus on the control of the hydrological and sedimentological connectivity at the catchment scale. For example, the density of the ditch network could be modified or the spatial distribution of vegetative filter strips used for sediment trapping could be optimized. In addition, the vegetative filter strips could constitute

  3. Will blocking historical drainage ditches increase carbon sequestration in upland blanket mires of Southwest England?

    Science.gov (United States)

    Le Feuvre, N.; Hartley, I.; Anderson, K.; Luscombe, D.; Grand-Clement, E.; Smith, D.; Brazier, R.

    2012-04-01

    Peat soils in the United Kingdom are estimated to store a minimum of 3,121Mt C (Lindsay, 2010). Despite being such a large carbon store the annual imbalance between uptake and release is small and susceptible to change in response to land management, atmospheric deposition and climate change. The upland blanket mires of Southwest England have been subject to extensive drainage and are particularly vulnerable to climate change as they lie at the lower edge of the peatland climatic envelope. The Mires-on-the-Moors project, funded by South West Water will restore over 2000 hectares of drained mire by April 2015. Herein, we question whether this restoration, which will block historical drainage ditches will allow the blanket bogs of Exmoor and Dartmoor National Parks to recover their ecohydrological functionality. We hypothesise that such mire restoration will increase the resilience of these ecosystems to climate change and will return these upland mires to peat forming/carbon sequestering systems. A method is proposed which aims to understand the processes driving gaseous carbon exchange and peat formation in an upland blanket bog and quantifies the effect restoration has on these processes. We propose to measure the spatial variation in gas fluxes with respect to structural features of the mire; drainage ditches and nanotopes. The role of vegetation; the community composition, phenology and health will be explored as well as environmental variables such as water table depths, temperature and photosynthetically active radiation. Importantly, the experiment will partition below ground respiration to assess the environmental controls and effect of restoration on autotrophic and heterotrophic respiration separately. Unusually, it will be possible to collect both pre- and post-restoration data for two experimental sites with existing intensive hydrological monitoring (baseline monitoring of water table depths at 15 minute timesteps has been in place for > 1 year at ca

  4. Determination of trace triazine and chloroacetamide herbicides in tile-fed drainage ditch water using solid-phase microextraction coupled with GC-MS

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Cleonice [Catholic University of Goias, Av. Universitaria, 1440 S. Universitario, Cx (Brazil); Pappas, Elizabeth A. [USDA ARS, National Soil Erosion Research Laboratory, 275 S. Russell Street, West Lafayette, IN 47907 (United States)], E-mail: bets@purdue.edu; Huang, C.-H. [USDA ARS, National Soil Erosion Research Laboratory, 275 S. Russell Street, West Lafayette, IN 47907 (United States)

    2008-03-15

    Solid-phase microextraction coupled with gas chromatography-mass spectrometry (SPME-GC-MS) was used to analyze two triazine (atrazine and simazine) and three chloroacetamide herbicides (acetochlor, alachlor, and metolachlor) in water samples from a midwest US agricultural drainage ditch for two growing seasons. The effects of salt concentration, sample volume, extraction time, and injection time on extraction efficiency using a 100-{mu}m polydimethylsiloxane-coated fiber were investigated. By optimizing these parameters, ditch water detection limits of 0.5 {mu}g L{sup -1} simazine and 0.25 {mu}g L{sup -1} atrazine, acetochlor, alachlor, and metolachlor were achieved. The optimum salt concentration was found to be 83% NaCl, while sample volume (10 or 20 mL) negligibly affected analyte peak areas. The optimum extraction time was 40 min, and the optimum injection time was 15 min. Results indicated that atrazine levels in the ditch water exceeded the US maximum contaminant level for drinking water 12% of the time, and atrazine was the most frequently detected among studied analytes. - Solid-phase microextraction methods were successfully developed to quantify low levels of herbicides in tile-fed drain water by gas chromatography-mass spectrometry.

  5. Evaluating toxicity of atrazine and lambda-cyhalothrin amendments in agricultural ditch mesocosms

    Science.gov (United States)

    Ditches running throughout and adjacent to agricultural lands serve primarily to remove and store excess water associated with storm events. More recently, these edge of field delivery systems have been investigated for their ability to mitigate potential contaminants. Six sites along a 50-m segme...

  6. Investigation of ground-water contamination at a drainage ditch, Installation Restoration Site 4, Naval Air Station Corpus Christi, Corpus Christi, Texas, 2005–06

    Science.gov (United States)

    Vroblesky, Don A.; Casey, Clifton C.

    2007-01-01

    The U.S. Geological Survey, in cooperation with the Naval Facilities Engineering Command Southeast, used newly developed sampling methods to investigate ground-water contamination by chlorobenzenes beneath a drainage ditch on the southwestern side of Installation Restoration Site 4, Naval Air Station Corpus Christi, Corpus Christi, Texas, during 2005-06. The drainage ditch, which is a potential receptor for ground-water contaminants from Installation Restoration Site 4, intermittently discharges water to Corpus Christi Bay. This report uses data from a new type of pore-water sampler developed for this investigation and other methods to examine the subsurface contamination beneath the drainage ditch. Analysis of ground water from the samplers indicated that chlorobenzenes (maximum detected concentration of 160 micrograms per liter) are present in the ground water beneath the ditch. The concentrations of dissolved oxygen in the samples (less than 0.05-0.4 milligram per liter) showed that the ground water beneath and near the ditch is anaerobic, indicating that substantial chlorobenzene biodegradation in the aquifer beneath the ditch is unlikely. Probable alternative mechanisms of chlorobenzene removal in the ground water beneath the drainage ditch include sorption onto the organic-rich sediment and contaminant depletion by cattails through uptake, sorption, and localized soil aeration.

  7. Enhancing the Biodiversity of Ditches in Intensively Managed UK Farmland.

    Directory of Open Access Journals (Sweden)

    Rosalind F Shaw

    Full Text Available Drainage ditches, either seasonally flooded or permanent, are commonly found on intensively managed lowland farmland in the UK. They are potentially important for wetland biodiversity but, despite their ubiquity, information on their biodiversity and management in the wider countryside is scarce. We surveyed 175 ditches for their physical and chemical characteristics, spatial connectivity, plant communities and aquatic invertebrates in an area of intensively managed farmland in Oxfordshire, UK and collected information on ditch management from farmer interviews. Water depth and shade had a small impact on the diversity of plant and invertebrate communities in ditches. Increased shade over the ditch channel resulted in reduced taxonomic richness of both channel vegetation and aquatic invertebrates and channel vegetation cover was lower at shaded sites. Invertebrate taxonomic richness was higher when water was deeper. Spatial connectivity had no detectable impact on the aquatic invertebrate or plant communities found in ditches. The number of families within the orders Ephemeroptera, Plecoptera and Trichoptera (EPT, which contain many pollution-sensitive species, declined with decreasing pH of ditch water. As time since dredging increased, the number of EPT families increased in permanent ditches but decreased in temporary ditches. Whether or not a ditch was in an agri-environment scheme had little impact on the reported management regime or biodiversity value of the ditch. Measures for increasing the amount of water in ditches, by increasing the water depth or promoting retention of water in ditches, could increase the biodiversity value of ditches in agricultural land. Some temporary ditches for specialised species should be retained. Reducing the amount of shade over narrow ditches by managing adjacent hedgerows is also likely to increase the species diversity of plant and invertebrate communities within the ditch. We recommend that to preserve

  8. Enhancing the Biodiversity of Ditches in Intensively Managed UK Farmland.

    Science.gov (United States)

    Shaw, Rosalind F; Johnson, Paul J; Macdonald, David W; Feber, Ruth E

    2015-01-01

    Drainage ditches, either seasonally flooded or permanent, are commonly found on intensively managed lowland farmland in the UK. They are potentially important for wetland biodiversity but, despite their ubiquity, information on their biodiversity and management in the wider countryside is scarce. We surveyed 175 ditches for their physical and chemical characteristics, spatial connectivity, plant communities and aquatic invertebrates in an area of intensively managed farmland in Oxfordshire, UK and collected information on ditch management from farmer interviews. Water depth and shade had a small impact on the diversity of plant and invertebrate communities in ditches. Increased shade over the ditch channel resulted in reduced taxonomic richness of both channel vegetation and aquatic invertebrates and channel vegetation cover was lower at shaded sites. Invertebrate taxonomic richness was higher when water was deeper. Spatial connectivity had no detectable impact on the aquatic invertebrate or plant communities found in ditches. The number of families within the orders Ephemeroptera, Plecoptera and Trichoptera (EPT), which contain many pollution-sensitive species, declined with decreasing pH of ditch water. As time since dredging increased, the number of EPT families increased in permanent ditches but decreased in temporary ditches. Whether or not a ditch was in an agri-environment scheme had little impact on the reported management regime or biodiversity value of the ditch. Measures for increasing the amount of water in ditches, by increasing the water depth or promoting retention of water in ditches, could increase the biodiversity value of ditches in agricultural land. Some temporary ditches for specialised species should be retained. Reducing the amount of shade over narrow ditches by managing adjacent hedgerows is also likely to increase the species diversity of plant and invertebrate communities within the ditch. We recommend that to preserve or enhance the

  9. Effect of the submergence, the bed form geometry, and the speed of the surface water flow on the mitigation of pesticides in agricultural ditches

    Science.gov (United States)

    Boutron, Olivier; Margoum, Christelle; Chovelon, Jean-Marc; Guillemain, CéLine; Gouy, VéRonique

    2011-08-01

    Pesticides, which have been extensively used in agriculture, have become a major environmental issue, especially regarding surface and groundwater contamination. Of particular importance are vegetated farm drainage ditches, which can play an important role in the mitigation of pesticide contamination by adsorption onto ditch bed substrates. This role is, however, poorly understood, especially regarding the influence of hydrodynamic parameters, which make it difficult to promote best management practice of these systems. We have assessed the influence of three of these parameters (speed of the surface water flow, submergence, and geometrical characteristics of the bed forms) on the transfer and adsorption of selected pesticides (isoproturon, diuron, tebuconazole, and azoxystrobin) into the bed substrate by performing experiments with a tilted experimental flume, using hemp fibers as a standard of natural organic substrates that are found at the bottom of agricultural ditches. Results show the transfer of pesticides from surface water flow into bed substrate is favored, both regarding the amounts transferred into the bed substrate and the kinetics of the transfer, when the surface water speed and the submergence increase and when the bed forms are made of rectangular shapes. Extrapolation of flume data over a distance of several hundred meters suggests that an interesting possibility for improving the mitigation of pesticides in ditches would be to increase the submergence and to favor bed forms that tend to enhance perturbations and subsequent infiltration of the surface water flow.

  10. Adaptation Options for Land Drainage Systems Towards Sustainable Agriculture and Environment: A Czech Perspective

    Science.gov (United States)

    Kulhavý, Zbyněk; Fučík, Petr

    2015-04-01

    In this paper, issues of agricultural drainage systems are introduced and discussed from the views of their former, current and future roles and functioning in the Czech Republic (CR). A methodologically disparate survey was done on thirty-nine model localities in CR with different intensity and state of land drainage systems, aimed at description of commonly occurred problems and possible adaptations of agricultural drainage as perceived by farmers, land owners, landscape managers or by protective water management. The survey was focused on technical state of drainage, fragmentation of land ownership within drained areas as well as on possible conflicts between agricultural and environmental interests in a landscape. Achieved results confirmed that there is obviously an increasing need to reassess some functions of prevailingly single-purpose agricultural drainage systems. Drainage intensity and detected unfavourable technical state of drainage systems as well as the risks connected with the anticipated climate change from the view of possible water scarcity claims for a complex solution. An array of adaptation options for agricultural drainage systems is presented, aiming at enhancement of water retention time and improvement of water quality. It encompasses additional flow-controlling measures on tiles or ditches, or facilities for making selected parts of a drainage system inoperable in order to retain or slow down the drainage runoff, to establish water accumulation zones and to enhance water self-cleaning processes. However, it was revealed that the question of landowner parcels fragmentation on drained land in CR would dramatically complicate design and realization of these measures. Presented solutions and findings are propounded with a respect to contemporary and future state policies and international strategies for sustainable agriculture, water management and environment.

  11. A two-dimensional transient analytical solution for a ponded ditch drainage system under the influence of source/sink

    Science.gov (United States)

    Sarmah, Ratan; Tiwari, Shubham

    2018-03-01

    An analytical solution is developed for predicting two-dimensional transient seepage into ditch drainage network receiving water from a non-uniform steady ponding field from the surface of the soil under the influence of source/sink in the flow domain. The flow domain is assumed to be saturated, homogeneous and anisotropic in nature and have finite extends in horizontal and vertical directions. The drains are assumed to be standing vertical and penetrating up to impervious layer. The water levels in the drains are unequal and invariant with time. The flow field is also assumed to be under the continuous influence of time-space dependent arbitrary source/sink term. The correctness of the proposed model is checked by developing a numerical code and also with the existing analytical solution for the simplified case. The study highlights the significance of source/sink influence in the subsurface flow. With the imposition of the source and sink term in the flow domain, the pathline and travel time of water particles started deviating from their original position and above that the side and top discharge to the drains were also observed to have a strong influence of the source/sink terms. The travel time and pathline of water particles are also observed to have a dependency on the height of water in the ditches and on the location of source/sink activation area.

  12. The impacts of ditch cuttings on weed pressure and crop yield in maize

    NARCIS (Netherlands)

    Huijser, M.P.; Meerburg, B.G.; Holshof, G.

    2004-01-01

    The Flevoland Polder in The Netherlands is characterised by large agricultural fields separated by ditches. The vegetation in the ditches is typically cut twice a year to ensure sufficient drainage. Removal of the cuttings, primarily reed (Phragmites australis), results in a substantial increase in

  13. Nitrate concentration-drainage flow (C-Q) relationship for a drained agricultural field in Eastern North Carolina Plain

    Science.gov (United States)

    Liu, W.; Youssef, M.; Birgand, F.; Chescheir, G. M.; Maxwell, B.; Tian, S.

    2017-12-01

    Agricultural drainage is a practice used to artificially enhance drainage characteristics of naturally poorly drained soils via subsurface drain tubing or open-ditch systems. Approximately 25% of the U.S. agricultural land requires improved drainage for economic crop production. However, drainage increases the transport of dissolved agricultural chemicals, particularly nitrates to downstream surface waters. Nutrient export from artificially drained agricultural landscapes has been identified as the leading source of elevated nutrient levels in major surface water bodies in the U.S. Controlled drainage has long been practiced to reduce nitrogen export from agricultural fields to downstream receiving waters. It has been hypothesized that controlled drainage reduces nitrogen losses by promoting denitrification, reducing drainage outflow from the field, and increasing plant uptake. The documented performance of the practice was widely variable as it depends on several site-specific factors. The goal of this research was to utilize high frequency measurements to investigate the effect of agricultural drainage and related management practices on nitrate fate and transport for an artificially drained agricultural field in eastern North Carolina. We deployed a field spectrophotometer to measure nitrate concentration every 45 minutes and measured drainage flow rate using a V-notch weir every 15 minutes. Furthermore, we measured groundwater level, precipitation, irrigation amount, temperature to characterize antecedent conditions for each event. Nitrate concentration-drainage flow (C-Q) relationships generated from the high frequency measurements illustrated anti-clockwise hysteresis loops and nitrate flushing mechanism in response to most precipitation and irrigation events. Statistical evaluation will be carried out for the C-Q relationships. The results of our analysis, combined with numerical modeling, will provide a better understanding of hydrological and

  14. Detecting Subsurface Agricultural Tile Drainage using GIS and Remote Sensing Technique

    Science.gov (United States)

    Budhathoki, M.; Gokkaya, K.; Tank, J. L.; Christopher, S. F.; Hanrahan, B.

    2015-12-01

    Subsurface tile drainage is a common practice in many of the row crop dominated agricultural lands in the Upper Midwest, which increases yield by making the soil more productive. It is reported that nearly half of all cropland in Indiana benefits from some sort of artificial drainage. However, subsurface tile has a significant negative impact on surface water quality by providing a fast means of transport for nutrients from fertilizers. Therefore, generating spatial data of tile drainage in the field is important and useful for agricultural landscape and hydrological studies. Subsurface tile drains in Indiana's croplands are not widely mapped. In this study, we will delineate subsurface tile drainage in agricultural land in Shatto Ditch watershed, located in Kosciusko County, Indiana. We will use geo-spatial methodology, which was purposed by earlier researchers to detect tile drainage. We will use aerial color-infrared and satellite imagery along with Light Detection and Ranging (LiDAR) data. In order to map tile lines with possible accuracy, we will use GIS-based analysis in combination with remotely sensed data. This research will be comprised of three stages: 1) masking out the potential drainage area using a decision tree rule based on land cover information, soil drainage category, surface slope, and satellite image differencing technique, 2) delineate tile lines using image processing techniques, and 3) check the accuracy of mapped tile lines with ground control points. To our knowledge, this study will be the first to check the accuracy of mapping with ground truth data. Based on the accuracy of results, we will extend the methodology to greater spatial scales. The results are expected to contribute to better characterizing and controlling water pollution sources in Indiana, which is a major environmental problem.

  15. Drainage filter technologies to mitigate site-specific phosphorus losses in agricultural drainage discharge

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Heckrath, Goswin Johann; Canga, Eriona

    in drainage. The Danish “SUPREME-TECH” project (2010-2016) (www.supreme-tech.dk) aims at providing the scientific basis for developing cost-effective filter technologies for P in agricultural drainage waters. The project studies different approaches of implementing filter technologies including drainage well....... Targeting high risk areas of P loss and applying site-specific measures promises to be a cost-efficient approach. The Danish Commission for Nature and Agriculture has, therefore, now called for a paradigm shift towards targeted, cost-efficient technologies to mitigate site-specific nutrient losses...... environmental threshold values (

  16. Modeling nutrient removal using watershed-scale implementation of the two-stage ditch

    Science.gov (United States)

    Western Lake Erie Basin (WLEB) is the most intensively farmed region of the Great Lakes. Because of the flat topography and poorly-drained soils many farmers rely on drainage management practices (e.g., subsurface tile drainage, ditch channelization) to maintain productive agriculture. However, th...

  17. Agriculture and wildlife: ecological implications of subsurface irrigation drainage

    Science.gov (United States)

    A. Dennis Lemly

    1994-01-01

    Subsurface agricultural irrigation drainage is a wastewater with the potential to severely impact wetlands and wildlife populations. Widespread poisoning of migratory birds by drainwater contaminants has occurred in the western United States and waterfowl populations are threatened in the Pacific and Central flyways. Irrigated agriculture could produce subsurface...

  18. Water quality issues associated with agricultural drainage in semiarid regions

    Science.gov (United States)

    Sylvester, Marc A.

    High incidences of mortality, birth defects, and reproductive failure in waterfowl using Kesterson Reservoir in the San Joaquin Valley, Calif., have occurred because of the bioaccumulation of selenium from irrigation drainage. These circumstances have prompted concern about the quality of agriculture drainage and its potential effects on human health, fish and wildlife, and beneficial uses of water. The U.S. Geological Survey (USGS) and Lawrence Berkeley Laboratory, University of California (Berkeley, Calif.) organized a 1-day session at the 1986 AGU Fall Meeting in San Francisco, Calif., to provide an interdisciplinary forum for hydrologists, geochemists, and aquatic chemists to discuss the processes controlling the distribution, mobilization, transport, and fate of trace elements in source rocks, soils, water, and biota in semiarid regions in which irrigated agriculture occurs. The focus of t h e session was the presentation of research results on the source, distribution, movement, and fate of selenium in agricultural drainage.

  19. Influence of three aquatic macrophytes on mitigation of nitrogen species from agricultural runoff

    Science.gov (United States)

    Agricultural runoff containing nitrogen fertilizer is a major contributor to eutrophication in aquatic systems. One method of lowering amounts of nitrogen entering rivers or lakes is the transport of runoff through vegetated drainage ditches. Drainage ditch vegetation can enhance the mitigation of...

  20. Continuous Passive Sampling of Solutes from Agricultural Subsurface Drainage Tubes

    Science.gov (United States)

    Lindblad Vendelboe, Anders; de Jonge, Hubert; Rozemeijer, Joachim; Wollesen de Jonge, Lis

    2015-04-01

    Agricultural subsurface tube drain systems play an important role in water and solute transport. One study, focusing on lowland agricultural catchments, showed that subsurface tube drainage contributed up to 80% of the annual discharge and 90% of the annual NO3 load from agricultural fields to the receiving water bodies. Knowledge of e.g. nutrient loads and drainage volumes, based on measurements and modelling, are important for adequate water quality management. Despite the importance of tube drain transport of solutes, monitoring data are scarce. This scarcity is a result of the existing monitoring techniques for flow and contaminant load from tube drains being expensive and labor-extensive. The study presented here aimed at developing a cheap, simple, and robust method to monitor solute loads from tube drains. The method is based on the newly developed Flowcap, which can be attached to existing tube drain outlets and can measure total flow, contaminant load and flow-averaged concentrations of solutes in the drainage. The Flowcap builds on the existing Sorbicell principle, a passive sampling system that measures average concentrations over longer periods of time (days to months) for various compounds. The Sorbicell consists of two compartments permeable to water. One compartment contains an adsorbent and one contains a tracer. When water passes through the Sorbicell the compound of interest is absorbed while a tracer is released. Using the tracer loss to calculate the volume of water that has passed the Sorbicell it is possible to calculate the average concentration of the compound. When mounting Sorbicells in the Flowcap, a flow-proportional part of the drainage is sampled from the main stream. To accommodate the wide range of drainage flow rates two Flowcaps with different capacities were tested in the laboratory: one with a capacity of 25 L min-1 (Q25) and one with a capacity of 256 L min-1 (Q256). In addition, Sorbicells with two different hydraulic

  1. Sorbents for phosphate removal from agricultural drainage water

    DEFF Research Database (Denmark)

    Lyngsie, Gry

    Subsurface transport of phosphate (P) from fertilized agricultural fields to freshwaters may lead to eutrophication and reduced biodiversity in inland waters. Mitigation of eutrophic waters is difficult and costly. Reduction of P export to surface waters using filters installed in agricultural...... drains comprising P sorbing materials (PSM) may be a more efficient and cost-effective way to improve water quality. Several materials have been proposed as PSMs for use for cleaning agricultural drainage water. The objective of the present study was to provide data on sorption behavior among a variety...... of PSMs in order to select a material that can quickly remove P from runoff water at both base and peak flow. This was done by screening 15 “local” PSMs’ for their ability to sorb and retain low orthophosphate concentrations (0-161 µM) at short equilibration time (

  2. 226Ra and 228Ra activities associated with agricultural drainage ponds and wetland ponds in the Kankakee Watershed, Illinois-Indiana, USA

    International Nuclear Information System (INIS)

    Sidle, W.C.; Shanklin, D.; Lee, P.Y.; Roose, D.L.

    2001-01-01

    Background radioactivity is elevated in many agricultural drainage ponds and also constructed wetland ponds in the Kankakee watershed. During 1995-1999, gross-α and -β activities were measured up to 455 and 1650 mBq L -1 , respectively. 226 Ra and 228 Ra averaged 139 and 192 mBq L -1 in controlled drainage ponds compared to 53 and 58 mBq L -1 for 226 Ra and 228 Ra, respectively, in native wetland ponds. Analyses of applied ammonium phosphate fertilizers near both native and controlled ponds indicate comparable 226 Ra/ 228 Ra and 228 Ra/ 232 Th activity ratios with only the surface waters in the controlled ponds. For example, 226 Ra/ 228 Ra activity ratios in controlled ponds ranged from 0.79 to 0.91 and group with a local fertilizer batch containing FL phosphate compounds with 226 Ra/ 228 Ra activity ratios of 0.83-1.04. Local soils of the Kankakee watershed have 226 Ra/ 228 Ra activity ratios of 0.54-0.70. Calculated Ra fluxes of waters, in drainage ditches associated with these controlled ponds, for 226 Ra ranged from 0.77 to 9.00 mBq cm -2 d -1 and for 228 Ra ranged from 1.22 to 8.43 mBq cm -2 d -1 . Ra activity gradients were measured beneath these controlled ponds both in agricultural landscapes and in constructed wetlands, all being associated with drainage ditches. Ra had infiltrated to the local water table but was below regulatory maximum contaminant limits. Still, measurable Ra activity was measured downgradient of even the constructed wetlands in the Kankakee watershed, suggesting that the attenuation of Ra was low. However, no Ra excess was observed in the riparian zone or the Kankakee River downgradient of the native wetland ponds

  3. Influence of particulates on phosphorus loading exported from farm drainage during a storm event in the Everglades Agricultural Area

    Science.gov (United States)

    Bhadha, J. H.; Lang, T. A.; Daroub, S. H.

    2015-12-01

    The purpose of this study was to evaluate the influence of particulates on P loading captured during a single storm event. The Everglades Agricultural Area of Florida comprises 280,000 hectares of organic soil farmland artificially drained by ditches, canals and pumps. Phosphorus (P)-enriched suspended particulates in canals are susceptible to transport and can contribute significantly to the overall P loads in drainage water. A settling tank experiment was conducted to capture particulates during tropical storm Isaac in 2012 from three farms approximately 2.4 to 3.6 km2 in size. Farm canal discharge water was collected in a series of two 200 liter settling tanks over a seven-day drainage period, during tropical storm Isaac. Water from the settling tanks was siphoned through Imhoff settling cones, where the particulates were allowed to settle and collected for P-fractionation analyses, and compared to intact sediment cores collected from the bottom of the canals. The discharged particulates contained higher organic matter content (OM), total P, and labile P fractions compared to the canal bottom sediments. Based on the equilibrium P concentrations, surface sediments behave as a source of P to the water column. A seven-day continuous drainage event exported 4.7 to 11.1 metric tons of suspended solids per farm, corresponding to 32 to 63 kg of particulate P being lost to downstream ecosystems. Drainage associated to a single seven-day storm event exported up to 61% of the total annual farm P load. It is evident from this study that short-term, high-intensity storm events can skew annual P loads due to the export of significantly higher particulate matter from farm canals. Exported particulates rich in P can provide a supplemental source of nutrients if captured and replenished back into the farmlands, as a sustainable farming practice.

  4. Irrigation and drainage in agriculture: a salinity and environmental perspective

    NARCIS (Netherlands)

    Zee, van der S.E.A.T.M.; Stofberg, S.F.; Yang, X.; Liu, Y.; Islam, M.N.; Hu, Yin Fei

    2017-01-01

    Whereas irrigation and drainage are intended to address the shortage and surplus of soil water, respectively, an important aspect to address is also the management of salinity. Plants have a limited tolerance for soil water salinity, and despite significant gaps in our practical knowledge, an

  5. Socially optimal drainage system and agricultural biodiversity: a case study for Finnish landscape.

    Science.gov (United States)

    Saikkonen, Liisa; Herzon, Irina; Ollikainen, Markku; Lankoski, Jussi

    2014-12-15

    This paper examines the socially optimal drainage choice (surface/subsurface) for agricultural crop cultivation in a landscape with different land qualities (fertilities) when private profits and nutrient runoff damages are taken into account. We also study the measurable social costs to increase biodiversity by surface drainage when the locations of the surface-drained areas in a landscape affect the provided biodiversity. We develop a general theoretical model and apply it to empirical data from Finnish agriculture. We find that for low land qualities the measurable social returns are higher to surface drainage than to subsurface drainage, and that the profitability of subsurface drainage increases along with land quality. The measurable social costs to increase biodiversity by surface drainage under low land qualities are negative. For higher land qualities, these costs depend on the land quality and on the biodiversity impacts. Biodiversity conservation plans for agricultural landscapes should focus on supporting surface drainage systems in areas where the measurable social costs to increase biodiversity are negative or lowest. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Integrating irrigation and drainage management to sustain agriculture in northern Iran

    NARCIS (Netherlands)

    Darzi-Naftchali, Abdullah; Ritzema, Henk

    2018-01-01

    In Iran, as in the rest of the world, land and water for agricultural production is under pressure. Integrating irrigation and drainage management may help sustain intensified agriculture in irrigated paddy fields. This study was aimed to investigate the long-term effects of such management

  7. Hydrology and Soil Manipulations of Iron-Rich Ditch Mesocosms Provide Little Evidence of Phosphorus Capture within the Profile.

    Science.gov (United States)

    Ruppert, David E; Needelman, Brian A; Kleinman, Peter J A; Rabenhorst, Martin C; Momen, Bahram; Wester, David B

    2017-05-01

    Agricultural drainage ditches function as first-order streams and affect nutrient management. Soil mesocosms from a ditch featuring a vertical (increasing upward) gradient in iron (Fe) and phosphorus (P) were subjected to hydraulic and soil treatments. These manipulations mimicked aspects of dredging and controlled drainage and inspected the soil release and retention of P. Treatments did not remove P from simulated groundwater. Throughput water either gained in P (lack of dredging, especially under Fe-reducing conditions) or had P concentrations indistinguishable from input water (dredging). Undredged mesocosms, when Fe-reducing, released Fe and P simultaneously. Simultaneous release of P and Fe from our Fe-reducing mesocosms indicates a mechanism whereby P capture occurs by Fe precipitation upon emergence to aerated surficial waters. Upwelling and surficial phases of ditch hydrology and the lowering of the ditch surface on dredging complicate interpretation of traditional means of describing ditch P retention and release. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  8. Fate of pesticides in field ditches: the TOXSWA simulation model

    NARCIS (Netherlands)

    Adriaanse, P.I.

    1996-01-01

    The TOXSWA model describes the fate of pesticides entering field ditches by spray drift, atmospheric deposition, surface run-off, drainage or leaching. It considers four processes: transport, transformation, sorption and volatilization. Analytical andnumerical solutions corresponded well. A sample

  9. Seasonal changes of fertilizer impacts on agricultural drainage in a salinized area in Adana, Turkey

    International Nuclear Information System (INIS)

    Kume, T.; Akca, E.; Nakano, T.; Nagano, T.; Kapur, S.; Watanabe, T.

    2010-01-01

    Seasonal changes in the impacts of fertilizer on the composition of agricultural drainage water were examined by analyzing the 87 Sr/ 86 Sr isotope ratio and chemical composition of drainage water samples. Samples of drainage water were taken from the main drainage canals of the Lower Seyhan Irrigation Project, at sites designated as D10, D11, and D12. Plots of 87 Sr/ 86 Sr vs. 1/Sr indicated that the 87 Sr/ 86 Sr ratio of drainage water was positively related to those of fertilizer and irrigation water. The origins of Sr in two of the end-components were fertilizer and irrigation water. The data from the end-drain in winter suggested that the origin of Sr in the third end-component was fossil seawater. Analysis of a mixing model incorporating these three end-components showed that the origins of Sr in drainage differed markedly between summer and winter. Fertilizer made the greatest contribution to Sr in drainage water both in summer and winter, contributing 38-72% of total Sr in summer and 64-87% of total Sr in winter. In summer, fertilizer contributed 72% of total Sr in drainage water in D12, 44% in D10, and 38% in D11. This result implies that fertilizer was applied excessively at the D12 site. In winter, seawater accounted for 10% of Sr in drainage water in D12, whereas it accounted for 19-27% of Sr in drainage water in D10 and D11. Therefore, at least 70% of the salt in drainage water originates from fertilizer and irrigation water. At this study site, the salt originating from seawater is replaced by that from fertilizer and irrigation water, due to intensive agricultural management. The study site is a delta that lay on the ocean subsurface at least 3000 years ago, and therefore, was originally a primary salinization area. This result suggests that anthropogenic secondary salinization progressed over time via fertilizer and irrigation applications.

  10. Batch Test Screening of Industrial Product/Byproduct Filter Materials for Agricultural Drainage Water Treatment

    Directory of Open Access Journals (Sweden)

    Barry J. Allred

    2017-10-01

    Full Text Available Filter treatment may be a viable means for removing the nitrate (NO3−, phosphate (PO43−, and pesticides discharged with agricultural drainage waters that cause adverse environmental impacts within the U.S. on local, regional, and national scales. Laboratory batch test screening for agricultural drainage water treatment potential was conducted on 58 industrial product/byproduct filter materials grouped into six categories: (1 high carbon content media; (2 high iron content media; (3 high aluminum content media; (4 surfactant modified clay/zeolite; (5 coal combustion residuals; and (6 spent foundry sands. Based on a percent contaminant removal criteria of 75% or greater, seven industrial products/byproducts were found to meet this standard for NO3− alone, 44 met this standard for PO43−, and 25 met this standard for the chlorinated triazine herbicide, atrazine. Using a 50% or greater contaminant removal criteria, five of the industrial product/byproduct filter materials exhibited potential for removing NO3−, PO43−, and atrazine together; eight showed capability for combined NO3− and PO43− removal; 21 showed capability for combined PO43− and atrazine removal; and nine showed capability for combined NO3− and atrazine removal. The results of this study delineated some potential industrial product/byproduct filter materials for drainage water treatment; however, a complete feasibility evaluation for drainage water treatment of any of these filter materials will require much more extensive testing.

  11. Effectiveness of the GAEC cross-compliance standard Short-term measures for runoff water control on sloping land (temporary ditches and grass strips in controlling soil erosion

    Directory of Open Access Journals (Sweden)

    Paolo Bazzoffi

    2011-08-01

    Full Text Available The agronomic measures made obligatory by the cross-compliance Standard Temporary measures for runoff water control on sloping land included in the Ministry of Agricultural, Food and Forestry Policies (MiPAAF decree on cross compliance until 2008, and by Standard 1.1 Creation of temporary ditches for the prevention of soil erosion in the 2009 decree, certainly appear to be useful for the control of soil erosion and runoff. The efficacy of temporary drainage ditches and of grass strips in controlling runoff and erosion has been demonstrated in trials conducted in field test plots in Italy. When level temporary drainage ditches are correctly built, namely with an inclination of not more than 2.5% in relation to the maximum hillslope gradient, they allow the suspended sediment eroded upstream to settle in the ditches, retaining the material carried away on the slope and, as a result, reducing the quantity of sediment delivered to the hydrographic network. In particular, among all the results, the erosion and runoff data in a trial conducted in Guiglia (Modena showed that in corn plots, temporary drainage ditches reduced soil erosion by 94%, from 14.4 Mg ha-1 year-1 (above the limit established by the NRCS-USDA of 11.2 Mg ha-1 year-1 to 0.8 Mg ha-1 year-1 (within the NRCS limit and also within the more restrictive limit established by the OECD of 6.0 Mg ha-1 year-1. With respect to the grass buffer strips the most significant research was carried out in Volterra. This research demonstrated their efficacy in reducing erosion from 8.15 Mg ha-1 to 1.6 Mg ha-1, which is approximately 5 times less than the erosion observed on bare soil. The effectiveness of temporary drainage ditches was also assessed through the application of the Revised Universal Soil Loss Equation (RUSLE erosion model to 60 areas under the control of the Agency for Agricultural Payments (AGEA in 2009, comparing the risk of erosion in these sample areas by simulating the presence and

  12. Phosphorus retention in a newly constructed wetland receiving agricultural tile drainage water.

    Science.gov (United States)

    Kynkäänniemi, Pia; Ulén, Barbro; Torstensson, Gunnar; Tonderski, Karin S

    2013-01-01

    One measure used in Sweden to mitigate eutrophication of waters is the construction of small wetlands (free water surface wetland for phosphorus retention [P wetlands]) to trap particulate phosphorus (PP) transported in ditches and streams. This study evaluated P retention dynamics in a newly constructed P wetland serving a 26-ha agricultural catchment with clay soil. Flow-proportional composite water samples were collected at the wetland inlet and outlet over 2 yr (2010-2011) and analyzed for total P (TP), dissolved P (DP), particulate P (PP), and total suspended solids (TSS). Both winters had unusually long periods of snow accumulation, and additional time-proportional water samples were frequently collected during snowmelt. Inflow TP and DP concentrations varied greatly (0.02-1.09 mg L) during the sampling period. During snowmelt in 2010, there was a daily oscillation in P concentration and water flow in line with air temperature variations. Outflow P concentrations were generally lower than inflow concentrations, with net P losses observed only in August and December 2010. On an annual basis, the wetland acted as a net P sink, with mean specific retention of 69 kg TP, 17 kg DP, and 30 t TSS ha yr, corresponding to a reduction in losses of 0.22 kg TP ha yr from the agricultural catchment. Relative retention was high (36% TP, 9% DP, and 36% TSS), indicating that small constructed wetlands (0.3% of catchment area) can substantially reduce P loads from agricultural clay soils with moderately undulating topography. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  13. Connectivity and propagule sources composition drive ditch plant metacommunity structure

    Science.gov (United States)

    Favre-Bac, Lisa; Ernoult, Aude; Mony, Cendrine; Rantier, Yann; Nabucet, Jean; Burel, Françoise

    2014-11-01

    The fragmentation of agricultural landscapes has a major impact on biodiversity. In addition to habitat loss, dispersal limitation increasingly appears as a significant driver of biodiversity decline. Landscape linear elements, like ditches, may reduce the negative impacts of fragmentation by enhancing connectivity for many organisms, in addition to providing refuge habitats. To characterize these effects, we investigated the respective roles of propagule source composition and connectivity at the landscape scale on hydrochorous and non-hydrochorous ditch bank plant metacommunities. Twenty-seven square sites (0.5 km2 each) were selected in an agricultural lowland of northern France. At each site, plant communities were sampled on nine ditch banks (totaling 243 ditches). Variables characterizing propagule sources composition and connectivity were calculated for landscape mosaic and ditch network models. The landscape mosaic influenced only non-hydrochorous species, while the ditch network impacted both hydrochorous and non-hydrochorous species. Non-hydrochorous metacommunities were dependent on a large set of land-use elements, either within the landscape mosaic or adjacent to the ditch network, whereas hydrochorous plant metacommunities were only impacted by the presence of ditches adjacent to crops and roads. Ditch network connectivity also influenced both hydrochorous and non-hydrochorous ditch bank plant metacommunity structure, suggesting that beyond favoring hydrochory, ditches may also enhance plant dispersal by acting on other dispersal vectors. Increasing propagule sources heterogeneity and connectivity appeared to decrease within-metacommunity similarity within landscapes. Altogether, our results suggest that the ditch network's composition and configuration impacts plant metacommunity structure by affecting propagule dispersal possibilities, with contrasted consequences depending on species' dispersal vectors.

  14. Estimating Impacts of Agricultural Subsurface Drainage on Evapotranspiration Using the Landsat Imagery-Based METRIC Model

    Directory of Open Access Journals (Sweden)

    Kul Khand

    2017-11-01

    Full Text Available Agricultural subsurface drainage changes the field hydrology and potentially the amount of water available to the crop by altering the flow path and the rate and timing of water removal. Evapotranspiration (ET is normally among the largest components of the field water budget, and the changes in ET from the introduction of subsurface drainage are likely to have a greater influence on the overall water yield (surface runoff plus subsurface drainage from subsurface drained (TD fields compared to fields without subsurface drainage (UD. To test this hypothesis, we examined the impact of subsurface drainage on ET at two sites located in the Upper Midwest (North Dakota-Site 1 and South Dakota-Site 2 using the Landsat imagery-based METRIC (Mapping Evapotranspiration at high Resolution with Internalized Calibration model. Site 1 was planted with corn (Zea mays L. and soybean (Glycine max L. during the 2009 and 2010 growing seasons, respectively. Site 2 was planted with corn for the 2013 growing season. During the corn growing seasons (2009 and 2013, differences between the total ET from TD and UD fields were less than 5 mm. For the soybean year (2010, ET from the UD field was 10% (53 mm greater than that from the TD field. During the peak ET period from June to September for all study years, ET differences from TD and UD fields were within 15 mm (<3%. Overall, differences between daily ET from TD and UD fields were not statistically significant (p > 0.05 and showed no consistent relationship.

  15. Long-term monitoring of nitrate transport to drainage from three agricultural clayey till fields

    Science.gov (United States)

    Ernstsen, V.; Olsen, P.; Rosenbom, A. E.

    2015-08-01

    The application of nitrogen (N) fertilisers to crops grown on tile-drained fields is required to sustain most modern crop production, but it poses a risk to the aquatic environment since tile drains facilitate rapid transport pathways with no significant reduction in nitrate. To maintain the water quality of the aquatic environment and the provision of food from highly efficient agriculture in line with the EU's Water Framework Directive and Nitrates Directive, field-scale knowledge is essential for introducing water management actions on-field or off-field and producing an optimal differentiated N-regulation in future. This study strives to provide such knowledge by evaluating on 11 years of nitrate-N concentration measurements in drainage from three subsurface-drained clayey till fields (1.3-2.3 ha) representing approximately 71 % of the surface sediments in Denmark dominated by clay. The fields differ in their inherent hydrogeological field settings (e.g. soil-type, geology, climate, drainage and groundwater table) and the agricultural management of the fields (e.g. crop type, type of N fertilisers and agricultural practices). The evaluation revealed three types of clayey till fields characterised by: (i) low net precipitation, high concentration of nitrate-N, and short-term low intensity drainage at air temperatures often below 5 °C; (ii) medium net precipitation, medium concentration of nitrate-N, and short-term medium-intensity drainage at air temperatures often above 5 °C; and (iii) high net precipitation, low concentration of nitrate-N and long-term high intensity drainage at air temperatures above 5 °C. For each type, on-field water management actions, such as the selection of crop types and introduction of catch crops, appeared relevant, whereas off-field actions only seemed relevant for the latter two field types given the temperature-dependent reduction potential of nitrate off-field. This initial well-documented field-scale knowledge from fields

  16. A dynamic model of soil salinity and drainage generation in irrigated agriculture: A framework for policy analysis

    Science.gov (United States)

    Dinar, Ariel; Aillery, Marcel P.; Moore, Michael R.

    1993-06-01

    This paper presents a dynamic model of irrigated agriculture that accounts for drainage generation and salinity accumulation. Critical model relationships involving crop production, soil salinity, and irrigation drainage are based on newly estimated functions derived from lysimeter field tests. The model allocates land and water inputs over time based on an intertemporal profit maximization objective function and soil salinity accumulation process. The model is applied to conditions in the San Joaquin Valley of California, where environmental degradation from irrigation drainage has become a policy issue. Findings indicate that in the absence of regulation, drainage volumes increase over time before reaching a steady state as increased quantities of water are allocated to leaching soil salts. The model is used to evaluate alternative drainage abatement scenarios involving drainage quotas and taxes, water supply quotas and taxes, and irrigation technology subsidies. In our example, direct drainage policies are more cost-effective in reducing drainage than policies operating indirectly through surface water use, although differences in cost efficiency are relatively small. In some cases, efforts to control drainage may result in increased soil salinity accumulation, with implications for long-term cropland productivity. While policy adjustments may alter the direction and duration of convergence to a steady state, findings suggest that a dynamic model specification may not be necessary due to rapid convergence to a comon steady state under selected scenarios.

  17. Agricultural pesticides in six drainage basins used for public water supply in New Jersey, 1990

    Science.gov (United States)

    Ivahnenko, Tamara; Buxton, D.E.

    1994-01-01

    A reconnaissance study of six drainage basins in New Jersey was conducted to evaluate the presence of pesticides from agricultural runoff in surface water. In the first phase of the study, surface-water public-supply drainage basins throughout New Jersey that could be affected by pesticide applications were identified by use of a Geographic Information System. Six basins--Lower Mine Hill Reservoir, South Branch of the Raritan River, Main Branch of the Raritan River, Millstone River, Manasquan River, and Matchaponix Brook--were selected as those most likely to be affected by pesticides on the basis of calculated pesticide-application rates and percentage of agricultural land. The second phase of the project was a short-term water-quality reconnaissance of the six drainage basins to determine whether pesticides were present in the surface waters. Twenty-eight surface-water samples (22 water-quality samples, 3 sequentially collected samples, and 3 trip blanks), and 6 samples from water-treatment facilities were collected. Excluding trip blanks, samples from water-treatment facilities, and sequentially collected samples, the pesticides detected in the samples and the percentage of samples in which they were detected, were as follows: atrazine and metolachlor, 86 percent; alachlor, 55 percent; simazine, 45 percent; diazinon, 27 percent; cyanazine and carbaryl, 23 percent; linuron and isophenfos, 9 percent; and chlorpyrifos, 5 percent.Diazinon, detected in one stormflow sample collected from Matchaponix Brook on August 6, 1990, was the only compound to exceed the U.S. Environmental Protection Agency's recommended Lifetime Health Advisory Limit. Correlation between ranked metolachlor concentrations and ranked flow rates was high, and 25 percent of the variance in metolachlor concentrations can be attributed to variations in flow rate. Pesticide residues were detected in samples of pretreated and treated water from water-treatment facilities. Concentrations of all

  18. Pesticide leaching by agricultural drainage in sloping, mid-textured soil conditions - the role of runoff components.

    Science.gov (United States)

    Zajíček, Antonín; Fučík, Petr; Kaplická, Markéta; Liška, Marek; Maxová, Jana; Dobiáš, Jakub

    2018-04-01

    Dynamics of pesticides and their metabolites in drainage waters during baseflow periods and rainfall-runoff events (RREs) were studied from 2014 to 2016 at three small, tile-drained agricultural catchments in Bohemian-Moravian Highlands, Czech Republic. Drainage systems in this region are typically built in slopes with considerable proportion of drainage runoff originating outside the drained area itself. Continuous monitoring was performed by automated samplers, and the event hydrograph was separated using 18 O and 2 H isotopes and drainage water temperature. Results showed that drainage systems represent a significant source for pesticides leaching from agricultural land. Leaching of pesticide metabolites was mainly associated with baseflow and shallow interflow. Water from causal precipitation diluted their concentrations. The prerequisites for the leaching of parental compounds were a rainfall-runoff event occurring shortly after spraying, and the presence of event water in the runoff. When such situations happened consequently, pesticides concentrations in drainage water were high and the pesticide load reached several grams in a few hours. Presented results introduce new insights into the processes of pesticides movement in small, tile-drained catchments and emphasizes the need to incorporate drainage hydrology and flow-triggered sampling into monitoring programmes in larger catchments as well as in environment-conservation policy.

  19. Capture and characterization of particulate phosphorus from farm drainage waters in the Everglades Agricultural Area

    Science.gov (United States)

    Bhadha, J. H.; Lang, T.; Daroub, S.

    2012-12-01

    The buildup of highly labile, organic, phosphorus (P)-enriched sediments in farms canals within the Everglades Agricultural Area (EAA) has been associated with the production of floating aquatic vegetation. During drainage events, these sediments are susceptible to transport and contribute to the overall P load. In order to evaluate the total P load exiting the farm canals, a settling tank experiment was conducted to capture the sediments during drainage events from eight farms. Drainage water was channelized through two 200L polypropylene collection tanks which allowed sediments to settle at the bottom based on its particle size. Water was carefully siphoned out of the tanks and the sediments collected for analyses. A five step P-fractionation process was used to distinguish organic (o) and inorganic (i) forms of P: KCl extractable P, NaOH extractable P, HCl extractable P, and residual P. The KCl-Pi fraction represents the labile Pi that is water soluble and exchangeable (loosely adsorbed); NaOH extractable P represents Fe- and Al- bound inorganic P (NaOH-Pi) and organic P associated with humic and fulvic acids (NaOH-Po). The HCl-Pi fraction includes Ca- and Mg- bound P, while Residue-P represents recalcitrant organic P compounds and P bound to minerals. The sediments were also used to conduct a P-flux study under both aerobic and anaerobic conditions. Our goal is to provide growers with vital information and insight into P loading that will help them in their efforts to reduce off-farm P loads in the EAA.

  20. Enabling proactive agricultural drainage reuse for improved water quality through collaborative networks and low-complexity data-driven modelling

    OpenAIRE

    Zia, Huma

    2015-01-01

    With increasing prevalence of Wireless Sensor Networks (WSNs) in agriculture and hydrology, there exists an opportunity for providing a technologically viable solution for the conservation of already scarce fresh water resources. In this thesis, a novel framework is proposed for enabling a proactive management of agricultural drainage and nutrient losses at farm scale where complex models are replaced by in-situ sensing, communication and low complexity predictive models suited to an autonomo...

  1. Resilience of Socio-Hydrological Systems in Canadian Prairies to Agricultural Drainage: Policy Analysis and Modelling Approach

    Science.gov (United States)

    Wheater, H. S.; Xu, L.; Gober, P.; Pomeroy, J. W.; Wong, J.

    2017-12-01

    Extensive agricultural drainage of lakes and wetlands in the Canadian Prairies has led to benefits for agricultural production, but has had a substantial influence on hydrological regimes and wetland extent. There is need for the potential impacts of current policy in changing the socio-hydrological resilience of prairie wetland basins in response to agricultural drainage to be examined. Whilst wetland drainage can increase agricultural productivity, it can also reduce stocks of natural capital and decrease ecosystem services, such as pollutant retention, habitat for waterfowls, carbon sequestration, and downstream flood attenuation. Effective policies that balance drainage benefits and negative externalities have to consider pricing. This is explored here using the Cold Regions Hydrological Model for hydrological simulations and the Inclusive Wealth approach for modelling in support of cost-benefit analysis. Inclusive wealth aggregates the value of natural, human, and technological assets used to produce social welfare. A shadow price, defined as the marginal change in social value for a marginal change in the current stock quantity, is used to valuate assets that contribute to social welfare. The shadow price of each asset is estimated by taking into account the social and economic benefits and external losses of wetland services caused by wetland drainage. The coupled model was applied to the Smith Creek Research Basin in south-eastern Saskatchewan, Canada where wetland drainage has caused major alterations of the hydrological regime including increased peak flows, discharge volumes and duration of streamflow. Changes in depressional storage in wetlands was used to calculate the corresponding changes of inclusive wealth over a 30-year period under the impacts from the limitation proposed in the Agricultural Water Management Strategy of Saskatchewan. The adjusted societal values of drainage demonstrate the dynamics between changes in hydrological conditions of

  2. Simulation-based optimization framework for reuse of agricultural drainage water in irrigation.

    Science.gov (United States)

    Allam, A; Tawfik, A; Yoshimura, C; Fleifle, A

    2016-05-01

    A simulation-based optimization framework for agricultural drainage water (ADW) reuse has been developed through the integration of a water quality model (QUAL2Kw) and a genetic algorithm. This framework was applied to the Gharbia drain in the Nile Delta, Egypt, in summer and winter 2012. First, the water quantity and quality of the drain was simulated using the QUAL2Kw model. Second, uncertainty analysis and sensitivity analysis based on Monte Carlo simulation were performed to assess QUAL2Kw's performance and to identify the most critical variables for determination of water quality, respectively. Finally, a genetic algorithm was applied to maximize the total reuse quantity from seven reuse locations with the condition not to violate the standards for using mixed water in irrigation. The water quality simulations showed that organic matter concentrations are critical management variables in the Gharbia drain. The uncertainty analysis showed the reliability of QUAL2Kw to simulate water quality and quantity along the drain. Furthermore, the sensitivity analysis showed that the 5-day biochemical oxygen demand, chemical oxygen demand, total dissolved solids, total nitrogen and total phosphorous are highly sensitive to point source flow and quality. Additionally, the optimization results revealed that the reuse quantities of ADW can reach 36.3% and 40.4% of the available ADW in the drain during summer and winter, respectively. These quantities meet 30.8% and 29.1% of the drainage basin requirements for fresh irrigation water in the respective seasons. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Reclaiming agricultural drainage water with nanofiltration membranes: Imperial Valley, California, USA

    Science.gov (United States)

    Kharaka, Y.K.; Schroeder, R.A.; Setmire, J.G.; ,

    2003-01-01

    We conducted pilot-scale field experiments using nanofiltration membranes to lower the salinity and remove Se, As and other toxic contaminants from saline agricultural wastewater in the Imperial Valley, California, USA. Farmlands in the desert climate (rainfall - 7.4 cm/a) of Imperial Valley cover -200,000 ha that are irrigated with water (-1.7 km3 annually) imported from the Colorado River. The salinity (-850 mg/L) and concentration of Se (-2.5 ??g/L) in the Colorado River water are high and evapotranpiration further concentrates salts in irrigation drainage water, reaching salinities of 3,000-15,000 mg/L TDS and a median Se value of -30 ??g/L. Experiments were conducted with two commercially available nanofiltration membranes, using drainage water of varying composition, and with or without the addition of organic precipitation inhibitors. Results show that these membranes selectively remove more than 95% of Se, SO4, Mo, U and DOC, and -30% of As from this wastewater. Low percentages of Cl, NO3 and HCO3, with enough cations to maintain electrical neutrality also were removed. The product water treated by these membranes comprised more than 90% of the wastewater tested. Results indicate that the treated product water from the Alamo River likely will have less than 0.2 ??g/L Se, salinity of 300-500 mg/L TDS and other chemical concentrations that meet the water quality criteria for irrigation and potable use. Because acceptability is a major issue for providing treated wastewater to urban centers, it may be prudent to use the reclaimed water for irrigation and creation of lower salinity wetlands near the Salton Sea; an equivalent volume of Colorado River water can then be diverted for the use of increasing populations of San Diego and other urban centers in southern California. Nanofiltration membranes yield greater reclaimed-water output and require lower pressure and less pretreatment, and therefore are generally more cost effective than traditional reverse

  4. Long-term monitoring of nitrate transport to drainage from three agricultural clayey till fields

    DEFF Research Database (Denmark)

    Ernstsen, Vibeke; Olsen, Preben; Rosenbom, Annette E.

    2015-01-01

    -regulation in future. This study strives to provide such knowledge by evaluating on 11 years of nitrate-N con-centration measurements in drainage from three subsurface-drained clayey till fields (1.3–2.3 ha) representing approxi-mately 71 % of the surface sediments in Denmark dominated by clay. The fields differ...... in their inherent hydrogeological field settings (e.g. soil-type, geology, climate, drainage and groundwater table) and the agricultural management of the fields (e.g. crop type, type of N fertilisers and agricultural practices). The evaluation revealed three types of clayey till fields characterised by: (i) low net...... precipitation, high concen-tration of nitrate-N, and short-term low intensity drainage at air temperatures often below 5 ◦C; (ii) medium net precip-itation, medium concentration of nitrate-N, and short-term medium-intensity drainage at air temperatures often above 5 ◦C; and (iii) high net precipitation, low...

  5. Seasonal variations of nitrogen and phosphorus retention in an agricultural drainage river in East China.

    Science.gov (United States)

    Chen, Dingjiang; Lu, Jun; Wang, Hailong; Shen, Yena; Kimberley, Mark O

    2010-02-01

    Riverine retention decreases loads of nitrogen (N) and phosphorus (P) in running water. It is an important process in nutrient cycling in watersheds. However, temporal riverine nutrient retention capacity varies due to changes in hydrological, ecological, and nutrient inputs into the watershed. Quantitative information of seasonal riverine N and P retention is critical for developing strategies to combat diffuse source pollution and eutrophication in riverine and coastal systems. This study examined seasonal variation of riverine total N (TN) and total P (TP) retention in the ChangLe River, an agricultural drainage river in east China. Water quality, hydrological parameters, and hydrophyte coverage were monitored along the ChangLe River monthly during 2004-2006. Nutrient export loads (including chemical fertilizer, livestock, and domestic sources) entering the river from the catchment area were computed using an export coefficient model based on estimated nutrient sources. Riverine TN and TP retention loads (RNRL and RPRL) were estimated using mass balance calculations. Temporal variations in riverine nutrient retention were analyzed statistically. Estimated annual riverine retention loads ranged from 1,538 to 2,127 t year(-1) for RNRL and from 79.4 to 90.4 t year(-1) for RPRL. Monthly retention loads varied from 6.4 to 300.8 t month(-1) for RNRL and from 1.4 to 15.3 t month(-1) for RPRL. Both RNRL and RPRL increased with river flow, water temperature, hydrophyte coverage, monthly sunshine hours, and total TN and TP inputs. Dissolved oxygen concentration and the pH level of the river water decreased with RNRL and RPRL. Riverine nutrient retention ratios (retention as a percentage of total input) were only related to hydrophyte coverage and monthly sunshine hours. Monthly variations in RNRL and RPRL were functions of TN and TP loads. Riverine nutrient retention capacity varied with environmental conditions. Annual RNRL and RPRL accounted for 30.3-48.3% and 52

  6. Water Quality Data from Two Agricultural Drainage Basins in Northwestern Indiana and Northeastern Illinois: I. Lagrangian and Synoptic Data, 1999-2002

    National Research Council Canada - National Science Library

    Antweiler, Ronald C; Smith, Richard L; Voytek, Mary A; Boehlke, John-Karl; Richards, Kevin D

    2004-01-01

    Methods of data collection and results of analyses are presented for Lagrangian and synoptic water-quality data collected from two agricultural drainages, the Iroquois River in northwestern Indiana...

  7. Long-term monitoring of nitrate-N transport to drainage from three agricultural clayey till fields

    Science.gov (United States)

    Ernstsen, V.; Olsen, P.; Rosenbom, A. E.

    2015-01-01

    The application of nitrogen (N) fertilisers to crops grown on tile-drained fields is necessary to sustain most modern crop production, but poses a risk to the aquatic environment since tile drains facilitate rapid transport pathways with no significant reduction in nitrate. To maintain the water quality of the aquatic environment and the provision of food from highly efficient agriculture in line with the EU's Water Framework Directive and Nitrates Directive, field-scale knowledge is imperative if there is to be differentiated N-regulation in future. This study describes nitrate-N leaching to drainage based on coherent monitoring of nitrate-N concentrations, the climate, the groundwater table and crop-specific parameters obtained over eleven years (2001-2011) at three subsurface-drained clayey till fields (1.3-2.3 ha). The monitoring results showed significant field differences in nitrate-N transport to drainage. Not only were these caused by periods of bare soil after short-season crops and N-fixing crops (pea), which have been shown to generate high nitrate-N concentrations in drainage, but by the hydrogeological field conditions that were shown to be the controlling factor of nitrate-N transport to drainage. The fields had the following characteristics: (A) the lowest mass transport (13 kg N ha-1) and fertiliser input had short-term and low-intensity drainage with the highest nitrate-N concentrations detected, representing 40% of net precipitation (226 mm) combined with low air temperatures, (B) the medium mass transport (14 kg N ha-1) had medium-term and medium-intensity drainage, representing 42% of net precipitation (471 mm) combined with periods of both low and higher air temperatures, (C) the highest mass transport (19 kg N ha-1) had long-term drainage, representing 68% of net precipitation (617 mm), but had the highest potential for in-situ soil denitrification and post-treatment (e.g. constructed wetlands) due to long periods with both high water

  8. Constructed wetlands targeting nitrogen removal in agricultural drainage discharge – a subcatchment scale mitigation strategy

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Hoffmann, Carl Christian; Bruun, Jacob Druedahl

    analysis of variable mitigation strategies and cost-efficiency analysis reveals that even at low to moderate yearly N removal efficiencies (20-25% N removal efficiency) CWs targeting drainage water are highly efficient and cost-efficient measures. Thus, although challenges remain regarding site......-specific documentations, CWs targeting drainage discharge has been included as new mitigation strategy in the Danish environmental regulation....... of recipients, drainage water nutrient loads have a major impact on water quality, and end-of-pipe drainage filter solution may offer the benefits of a targeted measure. This calls for a paradigm shift towards the development of new, cost-efficient technologies to mitigate site-specific nutrient losses...

  9. Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events.

    Science.gov (United States)

    Bhadha, Jehangir H; Sexton, Anne; Lang, Timothy A; Daroub, Samira H

    2017-11-07

    The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage discharge events. Farm canals can be enriched by nutrients such as phosphorus (P) that are susceptible to transport. Phosphorus in the form of suspended particulates can significantly contribute to the overall P loads in drainage water. A settling tank experiment was conducted to capture suspended particulates during discrete drainage events. Farm canal discharge water was collected in a series of two 200 L settling tanks over the entire duration of the drainage event, so as to represent a composite subsample of the water being discharged. Imhoff settling cones are ultimately used to settle out the suspended particulates. This is achieved by siphoning water from the settling tanks via the cones. The particulates are then collected for physico-chemical analyses.

  10. Metals in agricultural produce associated with acid-mine drainage in Mount Morgan (Queensland, Australia).

    Science.gov (United States)

    Vicente-Beckett, Victoria A; McCauley, Gaylene J Taylor; Duivenvoorden, Leo J

    2016-01-01

    Acid-mine drainage (AMD) into the Dee River from the historic gold and copper mine in Mount Morgan, Queensland (Australia) has been of concern to farmers in the area since 1925. This study sought to determine the levels of AMD-related metals and sulfur in agricultural produce grown near the mine-impacted Dee River, compare these with similar produce grown in reference fields (which had no known AMD influence), and assess any potential health risk using relevant Australian or US guidelines. Analyses of lucerne (Medicago sativa; also known as alfalfa) from five Dee fields showed the following average concentrations (mg/kg dry basis): Cd < 1, Cu 11, Fe 106, Mn 52, Pb < 5, Zn 25 and S 3934; similar levels were found in lucerne hay (used as cattle feed) from two Dee fields. All lucerne and lucerne hay data were generally comparable with levels found in the lucerne reference fields, suggesting no AMD influence; the levels were within the US National Research Council (US NRC) guidelines for maximum tolerable cattle dietary intake. Pasture grass (also cattle feed) from two fields in the Dee River floodplains gave mean concentrations (mg/kg dry) of Cd 0.14, Cu 12, Fe 313, Mn 111, Pb 1.4, Zn 86 and S 2450. All metal levels from the Dee and from reference sites were below the US NRC guidelines for maximum tolerable cattle dietary intake; however, the average Cd, Cu and Fe levels in Dee samples were significantly greater than the corresponding levels in the pasture grass reference sites, suggesting AMD influence in the Dee samples. The average levels in the edible portions of mandarin oranges (Citrus reticulata) from Dee sites (mg/kg wet weight) were Cd 0.011, Cu 0.59, Fe 2.2, Mn 0.56, Pb 0.18, S 91 and Zn 0.96. Cd and Zn were less than or close to, average Fe and Mn levels were at most twice, Cd 1.8 or 6.5 times, and Pb 8.5 or 72 times the maximum levels in raw oranges reported in the US total diet study (TDS) or the Australian TDS, respectively. Average Cd, Fe, Mn, Pb and

  11. Removal of phosphorus from agricultural wastewaters using adsorption media prepared from acid mine drainage sludge

    Science.gov (United States)

    Sibrell, Philip L.; Montgomery, Gary A.; Ritenour, Kelsey L.; Tucker, Travis W.

    2009-01-01

    Excess phosphorus in wastewaters promotes eutrophication in receiving waterways. A??cost-effective method for the removal of phosphorus from water would significantly reduce the impact of such wastewaters on the environment. Acid mine drainage sludge is a waste product produced by the neutralization of acid mine drainage, and consists mainly of the same metal hydroxides used in traditional wastewater treatment for the removal of phosphorus. In this paper, we describe a method for the drying and pelletization of acid mine drainage sludge that results in a particulate media, which we have termed Ferroxysorb, for the removal of phosphorus from wastewater in an efficient packed bed contactor. Adsorption capacities are high, and kinetics rapid, such that a contact time of less than 5 min is sufficient for removal of 60-90% of the phosphorus, depending on the feed concentration and time in service. In addition, the adsorption capacity of the Ferroxysorb media was increased dramatically by using two columns in an alternating sequence so that each sludge bed receives alternating rest and adsorption cycles. A stripping procedure based on treatment with dilute sodium hydroxide was also developed that allows for recovery of the P from the media, with the possibility of generating a marketable fertilizer product. These results indicate that acid mine drainage sludges - hitherto thought of as undesirable wastes - can be used to remove phosphorus from wastewater, thus offsetting a portion of acid mine drainage treatment costs while at the same time improving water quality in sensitive watersheds.

  12. An accurate and stable nitrate-selective electrode for the in situ determination of nitrate in agricultural drainage waters.

    Science.gov (United States)

    Le Goff, Thierry; Braven, Jim; Ebdon, Les; Chilcottt, Neil P; Scholefield, David; Wood, John W

    2002-04-01

    A field evaluation of a novel nitrate-ion selective electrode (ISE) was undertaken by continuous immersion over a period of 5 months in agricultural drainage weirs. The nitrate sensor N,N,N-triallyl leucine betaine was covalently attached to polystyrene-block-polybutadiene-block-polystyrene (SBS) using a free radical initiated co-polymerisation, to produce a rubbery membrane which was incorporated into a commercially available electrode body. A measurement unit was constructed comprising the nitrate-ISEs, a reference electrode and a temperature probe connected through a pre-amplifier to a data-logger and battery supply. A temperature correction algorithm was developed to accomodate the temperature changes encountered in the drainage weirs. The nitrate results obtained with the ISEs at hourly intervals compared very favourably (R2 = 0.99) with those obtained with laboratory automated chemical determinations made on contemporaneous samples of drainage in a concentration range 0.47-16 ppm nitrate-N. The ISEs did not require re-calibration and no deterioration in performance or fouling of the membrane surface was observed over four months of deployment.

  13. Policy Incentives for Reducing Nitrate Leaching in Agricultural Lands: A Case Study of Irrigation and Drainage Dorudzan

    International Nuclear Information System (INIS)

    Sheikhzeinoddin, A.; Esmaeili, A.; Zibaei, M.

    2016-01-01

    Agricultural activities increasingly use water, fertilizers and pesticides, which may generate negative impacts on environment. Nowadays, nitrogen leaching from agricultural lands is a widespread global problem. Therefore, alternative land management practices such as nutrient management (rate, method and time of application), tillage operations (conservation and no-tillage), and irrigation management are routinely used to reduce non-point source pollution and improve water quality. In fact, a number of studies have illustrated the positive effects of best management practices on water and nutrient losses. The objective of this paper is to develop a bio-economic model and introducing the policy instrument for reducing nitrate from irrigation and drainage Dorudzan. We aim to identify ‘‘win–win’’ opportunities for improving farm profitability and reducing nitrate leaching.

  14. Effects of Aeration, Vegetation, and Iron Input on Total P Removal in a Lacustrine Wetland Receiving Agricultural Drainage

    Directory of Open Access Journals (Sweden)

    Yuanchun Zou

    2018-01-01

    Full Text Available Utilizing natural wetlands to remove phosphorus (P from agricultural drainage is a feasible approach of protecting receiving waterways from eutrophication. However, few studies have been carried out about how these wetlands, which act as buffer zones of pollutant sinks, can be operated to achieve optimal pollutant removal and cost efficiency. In this study, cores of sediments and water were collected from a lacustrine wetland of Lake Xiaoxingkai region in Northeastern China, to produce a number of lab-scale wetland columns. Ex situ experiments, in a controlled environment, were conducted to study the effects of aeration, vegetation, and iron (Fe input on the removal of total P (TP and values of dissolved oxygen (DO and pH of the water in these columns. The results demonstrated the links between Fe, P and DO levels. The planting of Glyceria spiculosa in the wetland columns was found to increase DO and pH values, whereas the Fe:P ratio was found to inversely correlate to the pH values. The TP removal was the highest in aerobic and planted columns. The pattern of temporal variation of TP removals matched first-order exponential growth model, except for under aerobic condition and with Fe:P ratio of 10:1. It was concluded that Fe introduced into a wetland by either surface runoff or agricultural drainage is beneficial for TP removal from the overlying water, especially during the growth season of wetland vegetation.

  15. Acceleration of selenium volatilization in seleniferous agricultural drainage sediments amended with methionine and casein

    International Nuclear Information System (INIS)

    Banuelos, G.S.; Lin, Z.-Q.

    2007-01-01

    Phytoremediation is potentially effective for managing excessive selenium (Se) in drainage sediment residing in the San Luis Drain in central California. This 2-year field study examined the feasibility of amending drainage sediment (containing 4.78 μg Se g -1 ) with methionine and casein to enhance volatilization without or with vegetation of Sporobolus airoides. Results show that without organic amendments, rates of Se volatilization were less than 25 μg m -2 d -1 in all plots. After amending the sediment with 71.4 mg methionine kg -1 soil, Se volatilization rates were 434 ± 107 μg m -2 d -1 in vegetated plots and 289 ± 117 μg m -2 d -1 in irrigated bare plots. With the amendment of 572 mg casein kg -1 soil, rates increased to 346 ± 103 μg m -2 d -1 in irrigated bare plots and to 114 ± 55 μg m -2 d -1 in vegetated plots. Both methionine and casein promoted biological remediation of Se via volatilization most effectively during the warmest months. - Amending drainage sediment with either methionine or casein promotes the volatilization of selenium

  16. Acceleration of selenium volatilization in seleniferous agricultural drainage sediments amended with methionine and casein

    Energy Technology Data Exchange (ETDEWEB)

    Banuelos, G.S. [USDA-ARS, Water Management Research Laboratory, Parlier, CA 93648 (United States)], E-mail: gbanuelos@fresno.ars.usda.gov; Lin, Z.-Q. [Department of Biological Sciences and Environmental Sciences Program, Southern Illinois University Edwardsville, Edwardsville, IL 62026-1651 (United States)

    2007-12-15

    Phytoremediation is potentially effective for managing excessive selenium (Se) in drainage sediment residing in the San Luis Drain in central California. This 2-year field study examined the feasibility of amending drainage sediment (containing 4.78 {mu}g Se g{sup -1}) with methionine and casein to enhance volatilization without or with vegetation of Sporobolus airoides. Results show that without organic amendments, rates of Se volatilization were less than 25 {mu}g m{sup -2} d{sup -1} in all plots. After amending the sediment with 71.4 mg methionine kg{sup -1} soil, Se volatilization rates were 434 {+-} 107 {mu}g m{sup -2} d{sup -1} in vegetated plots and 289 {+-} 117 {mu}g m{sup -2} d{sup -1} in irrigated bare plots. With the amendment of 572 mg casein kg{sup -1} soil, rates increased to 346 {+-} 103 {mu}g m{sup -2} d{sup -1} in irrigated bare plots and to 114 {+-} 55 {mu}g m{sup -2} d{sup -1} in vegetated plots. Both methionine and casein promoted biological remediation of Se via volatilization most effectively during the warmest months. - Amending drainage sediment with either methionine or casein promotes the volatilization of selenium.

  17. Assessment of agricultural drainage water quality for safe reuse in irrigation applications-a case study in Borg El-Arab, Alexandria

    Directory of Open Access Journals (Sweden)

    Mahmoud Nasr

    2015-03-01

    Full Text Available Objective: To demonstrate the technical feasibility of the reuse of agricultural drainage water for irrigation. Methods: The agricultural drainage water near Banjar El-Sokar, Borg El-Arab City, Alexandria, Egypt was collected. The measured heavy metals in the drainage water were compared with the permissible levels stated in environmental regulations, Law No. 48 of 1982 concerning the protection of the Nile River and waterways from pollution. Results: Heavy metals and trace elements were detected in this agricultural drainage water as following: Al (1.64 mg/L, Ca (175.00 mg/L, Cd (1.87 mg/L, Co (2.23 mg/L, Cu (1.71 mg/L, Fe (1.64 mg/L, K (20.50 mg/L, and Pb (2.81 mg/L. According to allowable limits, item such as Fe is lower than permissible level of 3.00 mg/L, while Pb and Cu are higher than 0.10 mg/L and 1.00 mg/L, respectively. Conclusions: Vegetables irrigated with such drainage water are not safe for human and animal consumption. Accordingly, the study suggests and recommeds remediation of drainage water using physical, chemical and/or biological methods.

  18. A paddy eco-ditch and wetland system to reduce non-point source pollution from rice-based production system while maintaining water use efficiency.

    Science.gov (United States)

    Xiong, Yujiang; Peng, Shizhang; Luo, Yufeng; Xu, Junzeng; Yang, Shihong

    2015-03-01

    Non-point source (NPS) pollution from agricultural drainage has aroused widespread concerns throughout the world due to its contribution to eutrophication of water bodies. To remove nitrogen (N) and phosphorus (P) from agricultural drainage in situ, a Paddy Eco-ditch and Wetland System (PEDWS) was designed and built based on the characteristics of the irrigated rice district. A 2-year (2012-2013) field experiment was conducted to evaluate the performance of this system in Gaoyou Irrigation District in Eastern China. The results showed that the reduction in water input in paddy field of the PEDWS enabled the maintenance of high rice yield; it significantly increased irrigation water productivity (WPI), gross water productivity (WPG), and evapotranspiration water productivity (WPET) by 109.2, 67.1, and 17.6%, respectively. The PEDWS dramatically decreased N and P losses from paddy field. Compared with conventional irrigation and drainage system (CIDS), the amount of drainage water from PEDWS was significantly reduced by 56.2%, the total nitrogen (TN) concentration in drainage was reduced by 42.6%, and thus the TN and total phosphorus (TP) losses were reduced by 87.8 and 70.4%. PEDWS is technologically feasible and applicable to treat nutrient losses from paddy fields in situ and can be used in similar areas.

  19. Nitrate-nitrogen losses through subsurface drainage under various agricultural land covers.

    Science.gov (United States)

    Qi, Zhiming; Helmers, Matthew J; Christianson, Reid D; Pederson, Carl H

    2011-01-01

    Nitrate-nitrogen (NO₃-N) loading to surface water bodies from subsurface drainage is an environmental concern in the midwestern United States. The objective of this study was to investigate the effect of various land covers on NO₃-N loss through subsurface drainage. Land-cover treatments included (i) conventional corn ( L.) (C) and soybean [ (L.) Merr.] (S); (ii) winter rye ( L.) cover crop before corn (rC) and before soybean (rS); (iii) kura clover ( M. Bieb.) as a living mulch for corn (kC); and (iv) perennial forage of orchardgrass ( L.) mixed with clovers (PF). In spring, total N uptake by aboveground biomass of rye in rC, rye in rS, kura clover in kC, and grasses in PF were 14.2, 31.8, 87.0, and 46.3 kg N ha, respectively. Effect of land covers on subsurface drainage was not significant. The NO₃-N loss was significantly lower for kC and PF than C and S treatments (p rye cover crop did not reduce NO₃-N loss, but NO₃-N concentration was significantly reduced in rC during March to June and in rS during July to November (p rye cover crop on NO-N loss reduction needs further investigation under conditions of different N rates, wider weather patterns, and fall tillage. by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  20. Nature of uranium contamination in the agricultural drainage water evaporation ponds of the San Joaquin Valley, California, USA

    International Nuclear Information System (INIS)

    Duff, M.C.; Amrhein, C.; Bradford, G.

    1997-01-01

    Evaporation ponds used for agricultural subsurface drainage water disposal in the Tulare Lake Bed (TLB) of the San Joaquin Valley, California, USA have elevated levels of U. Waterfowl which inhabit and forage the ponds and surrounding areas are threatened by exposure to U. The ponds, which receive irrigation drainage waters and seasonal rain, are subject to wetting and drying periods. The periods result in the accumulation of decaying algae and other organic material in surface sediments. Sediment and waters in the ponds were sampled to determine what factors control U solubility and sediment U concentrations. Data from a 1990 study conducted by Chilcott et al. in 1989 on the TLB ponds were used to help identify what factors may control U solubility. Pond sediment U concentrations decreased abruptly with depth and surface sediment U concentrations were related to dissolved Ca:HCO 3 ratios. Pond algal U bioaccumulation was favored in waters with high Ca:HCO 3 ratios, which had lower pH values and carbonate alkalinities than waters with low CA:HCO 3 ratios. Ponds with high salinities and high carbonate alkalinities contained the highest aqueous U concentrations relative to other TLB ponds. Sediment total organic carbon (TOC) was correlated with sediment U concentrations, suggesting that U is bound to organic matter. The source of TOC is most likely from algae deposition. (author)

  1. Heavy metals in agricultural landscapes as hazards to human and ecosystem health: a case study on zinc and cadmium in drainage channel sediments.

    Science.gov (United States)

    Savic, Radovan; Ondrasek, Gabrijel; Josimov-Dundjerski, Jasmina

    2015-02-01

    In agricultural systems, heavy metals pose severe risks to the health of soil-plant-animal-human continuum. Drainage channels, as integral components of agricultural landscapes, contain sediment material that can be both a source and a sink of metals and other toxic/persistent elements due to its highly reactive interfaces and strong binding affinity. The drainage channel network in a case study area of Vojvodina (Serbia) is not appropriately protected from contamination, nor is it maintained regularly (e.g. by desilting), thus endangering and potentially decreasing the ecological value of surrounding water and agricultural land resources, i.e. exposing food production to potential contaminants. In this study (2004-2012), Cd and Zn concentrations were analysed in 100 samples from 46 drainage channels sediments spread along the areas of the most intensive agricultural land use in Vojvodina. Among the samples measured, 5% had Cd and 14% had Zn concentrations above the maximally permitted levels, indicating that some drainage channel sections have been exposed to different point and non-point source pollutants. The maximum detected concentrations of the analysed elements were >50% (Zn) and were as much as 11-fold (Cd) higher than their remediation values. There is a strong need for the establishment of qualitative monitoring of channel sediment media in agro-ecosystems closely linked with complex pollution sources (intensive agriculture, industry, urban zones). © 2013 Society of Chemical Industry.

  2. Root-Zone Glyphosate Exposure Adversely Affects Two Ditch Species

    Directory of Open Access Journals (Sweden)

    Lyndsay E. Saunders

    2013-12-01

    Full Text Available Glyphosate, one of the most applied herbicides globally, has been extensively studied for its effects on non-target organisms. In the field, following precipitation, glyphosate runs off into agricultural ditches where it infiltrates into the soil and thus may encounter the roots of vegetation. These edge-of-field ditches share many characteristics with wetlands, including the ability to reduce loads of anthropogenic chemicals through uptake, transformation, and retention. Different species within the ditches may have a differential sensitivity to exposure of the root zone to glyphosate, contributing to patterns of abundance of ruderal species. The present laboratory experiment investigated whether two species commonly found in agricultural ditches in southcentral United States were affected by root zone glyphosate in a dose-dependent manner, with the objective of identifying a sublethal concentration threshold. The root zone of individuals of Polygonum hydropiperoides and Panicum hemitomon were exposed to four concentrations of glyphosate. Leaf chlorophyll content was measured, and the ratio of aboveground biomass to belowground biomass and survival were quantified. The findings from this study showed that root zone glyphosate exposure negatively affected both species including dose-dependent reductions in chlorophyll content. P. hydropiperdoides showed the greatest negative response, with decreased belowground biomass allocation and total mortality at the highest concentrations tested.

  3. Shifts in functional plant groups in ditch banks under agri-environment schemes and in nature reserves

    NARCIS (Netherlands)

    Dijk, van W.F.A.; Schaffers, A.P.; Ruijven, van J.; Berendse, F.; Snoo, de G.R.

    2013-01-01

    Management of ditch banks of agricultural fields is considered to be a promising and multifunctional application of agri-environment schemes (AES) on farmland. Our previous research has shown that in the Netherlands, there is a small increase in the number of target plant species of AES in ditch

  4. Phosphorus retention in surface-flow constructed wetlands targeting agricultural drainage water

    DEFF Research Database (Denmark)

    Dantas Mendes, Lipe Renato; Tonderski, Karin; Iversen, Bo Vangsø

    2018-01-01

    Surface-flow constructed wetlands (CWs) are potential cost-efficient solutions to mitigate phosphorus (P) loads from agricultural areas to surface waters. Hydraulic and phosphorus loading rates (HLR and PLR) are critical parameters that regulate P retention in these systems. The present study aim...

  5. Ditch network maintenance in peat-dominated boreal forests: Review and analysis of water quality management options.

    Science.gov (United States)

    Nieminen, Mika; Piirainen, Sirpa; Sikström, Ulf; Löfgren, Stefan; Marttila, Hannu; Sarkkola, Sakari; Laurén, Ari; Finér, Leena

    2018-03-27

    The objective of this study was to evaluate the potential of different water management options to mitigate sediment and nutrient exports from ditch network maintenance (DNM) areas in boreal peatland forests. Available literature was reviewed, past data reanalyzed, effects of drainage intensity modeled, and major research gaps identified. The results indicate that excess downstream loads may be difficult to prevent. Water protection structures constructed to capture eroded matter are either inefficient (sedimentation ponds) or difficult to apply (wetland buffers). It may be more efficient to decrease erosion, either by limiting peak water velocity (dam structures) or by adjusting ditch depth and spacing to enable satisfactory drainage without exposing the mineral soil below peat. Future research should be directed towards the effects of ditch breaks and adjusted ditch depth and spacing in managing water quality in DNM areas.

  6. Simulation of Nitrogen and Phosphorus Removal in Ecological Ditch Based on EFDC Model

    Science.gov (United States)

    Li, S. M.; Wang, X. L.; Zhou, Q. Y.; Han, N. N.

    2018-03-01

    Agricultural non-point source pollution threatens water quality and ecological system recently. To control it, the first and most important task is to control the migration and transformation of nitrogen and phosphorus in the agricultural ditches. An ecological ditch was designed, and according to the design a pilot device was built, the mechanism of N and P removal in ditches under the collaboration of aquatic organisms-hydraulic power was studied through the dynamic and static experiments, in order to find out the specific influences of different environmental factors such as influent concentration, influent flow and water level. The transport and diffusion of N and P in the ditch was simulated by a three dimensional water quality model EFDC, the simulation results and the experimental data were compared. The average relative errors of EFDC model simulated results were all less than 15%, which verified the reliability of the model.

  7. Long-Term Observations of Nitrogen and Phosphorus Export in Paired-Agricultural Watersheds under Controlled and Conventional Tile Drainage.

    Science.gov (United States)

    Sunohara, M D; Gottschall, N; Wilkes, G; Craiovan, E; Topp, E; Que, Z; Seidou, O; Frey, S K; Lapen, D R

    2015-09-01

    Controlled tile drainage (CTD) regulates water and nutrient export from tile drainage systems. Observations of the effects of CTD imposed en masse at watershed scales are needed to determine the effect on downstream receptors. A paired-watershed approach was used to evaluate the effect of field-to-field CTD at the watershed scale on fluxes and flow-weighted mean concentrations (FWMCs) of N and P during multiple growing seasons. One watershed (467-ha catchment area) was under CTD management (treatment [CTD] watershed); the other (250-ha catchment area) had freely draining or uncontrolled tile drainage (UCTD) (reference [UCTD] watershed). The paired agricultural watersheds are located in eastern Ontario, Canada. Analysis of covariance and paired tests were used to assess daily fluxes and FWMCs during a calibration period when CTD intervention on the treatment watershed was minimal (2005-2006, when only 4-10% of the tile-drained area was under CTD) and a treatment period when the treatment (CTD) watershed had prolific CTD intervention (2007-2011 when 82% of tile drained fields were controlled, occupying >70% of catchment area). Significant linear regression slope changes assessed using ANCOVA ( ≤ 0.1) for daily fluxes from upstream and downstream monitoring sites pooled by calibration and treatment period were -0.06 and -0.20 (stream water) (negative values represent flux declines in CTD watershed), -0.59 and -0.77 (NH-N), -0.14 and -0.15 (NO-N), -1.77 and -2.10 (dissolved reactive P), and -0.28 and 0.45 (total P). Total P results for one site comparison contrasted with other findings likely due to unknown in-stream processes affecting total P loading, not efficacy of CTD. The FWMC results were mixed and inconclusive but suggest physical abatement by CTD is the means by which nutrient fluxes are predominantly reduced at these scales. Overall, our study results indicate that CTD is an effective practice for reducing watershed scale fluxes of stream water, N, and P

  8. Transport of mecoprop from agricultural soils to an adjacent salt marsh

    International Nuclear Information System (INIS)

    Fletcher, Caroline A.; Scrimshaw, Mark D.; Lester, John N.

    2004-01-01

    Salt marshes are important ecological areas and play a significant role in coastal flood defence schemes. In many areas of the UK they are adjacent to agricultural areas utilised for the growth of cereal crops, for which mecoprop is used as a selective herbicide in the control of broad-leafed weeds. This study measured concentrations of mecoprop in soils, drainage ditch waters and sediments and salt marsh sediments over a period of 138 days following spring application. Soil concentrations of up to 1827 μg/g were recorded after application, which demonstrated a half life for mecoprop of from 9 to 12 days, with first order kinetics. However, a major rainfall event 9 days after application resulted in significant transport of herbicide to the salt marsh via subsurface field drains, drainage ditches and discharge sluice. Mecoprop concentrations of up to 386 μg/l observed in water samples were above UK guidelines

  9. Assessing the efficiency of Mediterranean ditch networks in preventing vineyards soil erosion within landscape

    Science.gov (United States)

    Levavasseur, Florent; Bailly, Jean-Stéphane; Lagacherie, Philippe

    2013-04-01

    Water erosion of cultivated soils is a threat to the sustainability of agriculture, especially in Mediterranean areas. For a long time, Mediterranean farmers have thus adopted some soil conservation practices. Actual ditch networks, which are generally associated with terraces, result from historical successive farmer settlements and are one of these soil conservation practices. By intercepting surface run-off, ditches decrease slope length and prevent soil erosion on downstream plots. However, since water erosion hazard and ditch network geometries are highly variable in vineyards landscape and since ditch building and maintaining are costly, the objective of this study was to identify and map the resulting efficiency of ditch networks in preventing soil erosion. For a given area, a ditch network efficiency is defined here as the balance between the network density, i.e. network cumulated length for a given area unit, and the erosion sensitivity over an area which measures the performance of the ditch network in limiting soil erosion. The erosion efficiency of ditch networks was thus identified using both i) computer generated ditch networks with various spatial configurations and ii) the stream power index as an erosion sensitivity indicator, computed from a DTM in which each ditch network was burned. The stream power index of the actual networks were compared with a set of generated networks whose density and topology were selected to maximize the performance in preventing soil erosion thanks to the use of a self-developed optimized stochastic network generator. For four 1 km² hillslopes, we showed that the performances of actual networks to prevent soil erosion was among the best that were obtained by simulated networks with even greater densities. Furthermore, we showed that the stream power index values that accounted for the actual ditch networks to prevent soil erosion hazard was both minimal and weakly variable in the whole study area (30 km²) at

  10. Spatial and temporal patterns of pesticide concentrations in streamflow, drainage and runoff in a small Swedish agricultural catchment.

    Science.gov (United States)

    Sandin, Maria; Piikki, Kristin; Jarvis, Nicholas; Larsbo, Mats; Bishop, Kevin; Kreuger, Jenny

    2018-01-01

    A better understanding of the dominant source areas and transport pathways of pesticide losses to surface water is needed for targeting mitigation efforts in a more cost-effective way. To this end, we monitored pesticides in surface water in an agricultural catchment typical of one of the main crop production regions in Sweden. Three small sub-catchments (88-242ha) were selected for water sampling based on a high-resolution digital soil map developed from proximal sensing methods and soil sampling; one sub-catchment had a high proportion of clay soils, another was dominated by coarse sandy soils while the third comprised a mix of soil types. Samples were collected from the stream, from field drains discharging into the stream and from within-field surface runoff during spring and early summer in three consecutive years. These samples were analyzed by LC-MS/MS for 99 compounds, including most of the polar and semi-polar pesticides frequently used in Swedish agriculture. Information on pesticide applications (products, doses and timing) was obtained from annual interviews with the farmers. There were clear and consistent differences in pesticide occurrence in the stream between the three sub-catchments, with both the numbers of detected compounds and concentrations being the largest in the area with a high proportion of clay soils and with very few detections in the sandy sub-catchment. Macropore flow to drains was most likely the dominant loss pathway in the studied area. Many of the compounds that were detected in drainage and stream water samples had not been applied for several years. This suggests that despite the predominant role of fast flow pathways in determining losses to the stream, long-term storage along the transport pathways also occurs, presumably in subsoil horizons where degradation is slow. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Using Campylobacter spp. and Escherichia coli data and Bayesian microbial risk assessment to examine public health risks in agricultural watersheds under tile drainage management.

    Science.gov (United States)

    Schmidt, P J; Pintar, K D M; Fazil, A M; Flemming, C A; Lanthier, M; Laprade, N; Sunohara, M D; Simhon, A; Thomas, J L; Topp, E; Wilkes, G; Lapen, D R

    2013-06-15

    Human campylobacteriosis is the leading bacterial gastrointestinal illness in Canada; environmental transmission has been implicated in addition to transmission via consumption of contaminated food. Information about Campylobacter spp. occurrence at the watershed scale will enhance our understanding of the associated public health risks and the efficacy of source water protection strategies. The overriding purpose of this study is to provide a quantitative framework to assess and compare the relative public health significance of watershed microbial water quality associated with agricultural BMPs. A microbial monitoring program was expanded from fecal indicator analyses and Campylobacter spp. presence/absence tests to the development of a novel, 11-tube most probable number (MPN) method that targeted Campylobacter jejuni, Campylobacter coli, and Campylobacter lari. These three types of data were used to make inferences about theoretical risks in a watershed in which controlled tile drainage is widely practiced, an adjacent watershed with conventional (uncontrolled) tile drainage, and reference sites elsewhere in the same river basin. E. coli concentrations (MPN and plate count) in the controlled tile drainage watershed were statistically higher (2008-11), relative to the uncontrolled tile drainage watershed, but yearly variation was high as well. Escherichia coli loading for years 2008-11 combined were statistically higher in the controlled watershed, relative to the uncontrolled tile drainage watershed, but Campylobacter spp. loads for 2010-11 were generally higher for the uncontrolled tile drainage watershed (but not statistically significant). Using MPN data and a Bayesian modelling approach, higher mean Campylobacter spp. concentrations were found in the controlled tile drainage watershed relative to the uncontrolled tile drainage watershed (2010, 2011). A second-order quantitative microbial risk assessment (QMRA) was used, in a relative way, to identify

  12. Cost-Effectiveness Analysis of Surface Flow Constructed Wetlands (SFCW) for Nutrient Reduction in Drainage Discharge from Agricultural Fields in Denmark.

    Science.gov (United States)

    Gachango, F G; Pedersen, S M; Kjaergaard, C

    2015-12-01

    Constructed wetlands have been proposed as cost-effective and more targeted technologies in the reduction of nitrogen and phosphorous water pollution in drainage losses from agricultural fields in Denmark. Using two pig farms and one dairy farm situated in a pumped lowland catchment as case studies, this paper explores the feasibility of implementing surface flow constructed wetlands (SFCW) based on their cost effectiveness. Sensitivity analysis is conducted by varying the cost elements of the wetlands in order to establish the most cost-effective scenario and a comparison with the existing nutrients reduction measures carried out. The analyses show that the cost effectiveness of the SFCW is higher in the drainage catchments with higher nutrient loads. The range of the cost effectiveness ratio on nitrogen reduction differs distinctively with that of catch crop measure. The study concludes that SFCW could be a better optimal nutrients reduction measure in drainage catchments characterized with higher nutrient loads.

  13. Performance of Iron Plaque of Wetland Plants for Regulating Iron, Manganese, and Phosphorus from Agricultural Drainage Water

    Directory of Open Access Journals (Sweden)

    Xueying Jia

    2018-01-01

    Full Text Available Agricultural drainage water continues to impact watersheds and their receiving water bodies. One approach to mitigate this problem is to use surrounding natural wetlands. Our objectives were to determine the effect of iron (Fe-rich groundwater on phosphorus (P removal and nutrient absorption by the utilization of the iron plaque on the root surface of Glyceria spiculosa (Fr. Schmidt. Rosh. The experiment was comprised of two main factors with three regimes: Fe2+ (0, 1, 20, 100, 500 mg·L−1 and P (0.01, 0.1, 0.5 mg·L−1. The deposition and structure of iron plaque was examined through a scanning electron microscope and energy-dispersive X-ray analyzer. Iron could, however, also impose toxic effects on the biota. We therefore provide the scanning electron microscopy (SEM on iron plaques, showing the essential elements were iron (Fe, oxygen (O, aluminum (Al, manganese (Mn, P, and sulphur (S. Results showed that (1 Iron plaque increased with increasing Fe2+ supply, and P-deficiency promoted its formation; (2 Depending on the amount of iron plaque on roots, nutrient uptake was enhanced at low levels, but at higher levels, it inhibited element accumulation and translocation; (3 The absorption of manganese was particularly affected by iron plague, which also enhanced phosphorus uptake until the external iron concentration exceeded 100 mg·L−1. Therefore, the presence of iron plaque on the root surface would increase the uptake of P, which depends on the concentration of iron-rich groundwater.

  14. 14 CFR 25.801 - Ditching.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ditching. 25.801 Section 25.801 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Emergency Provisions § 25.801 Ditching. (a...

  15. Testing of DRAINMOD for Forested Watersheds with Non-Pattern Drainage

    Science.gov (United States)

    Devendra M. Amatya; Ge Sun; R. Wayne Skaggs; Carl C. Trettin

    2003-01-01

    Models like DRAINMOD and its forestry version, DRAINLOB, have been specifically developed as a field scale model for evaluating hydrologic effects of crops (trees), soil, and water management practices for lands with pattern drainage (i.e. with parallel ditches) on relatively flat, high water table soils. These models conduct a water balance between the ditches to...

  16. Assessment of waterlogging in agricultural megaprojects in the closed drainage basins of the Western Desert of Egypt

    Directory of Open Access Journals (Sweden)

    M. El Bastawesy

    2013-04-01

    Full Text Available This paper investigates the development of waterlogging in the cultivated and arable areas within typical dryland closed drainage basins (e.g. the Farafra and Baharia Oases, which are located in the Western Desert of Egypt. Multi-temporal remote sensing data of the Landsat Thematic Mapper (TM and Enhanced Thematic Mapper (ETM+ were collected and processed to detect the land cover changes; cultivations, and the extent of water ponds and seepage channels. The Shuttle Radar Topography Mission (SRTM digital elevation model (DEM has been processed to delineate the catchment morphometrical parameters (i.e. drainage networks, catchment divides and surface areas of different basins and to examine the spatial distribution of cultivated fields and their relation to the extracted drainage networks. The soil of these closed drainage basins is mainly shallow and lithic with high calcium carbonate content; therefore, the downward percolation of excess irrigation water is limited by the development of subsurface hardpan, which also saturates the upper layer of soil with water. The subsurface seepage from the newly cultivated areas in the Farafra Oasis has revealed the pattern of buried alluvial channels, which are waterlogged and outlined by the growth of diagnostic saline shrubs. Furthermore, the courses of these waterlogged channels are coinciding with their counterparts of the SRTM DEM, and the recent satellite images show that the surface playas in the downstream of these channels are partially occupied by water ponds. On the other hand, a large water pond has occupied the main playa and submerged the surrounding fields, as a large area has been cultivated within a relatively small closed drainage basin in the Baharia Oasis. The geomorphology of closed drainage basins has to be considered when planning for a new cultivation in dryland catchments to better control waterlogging hazards. The "dry-drainage" concept can be implemented as the drainage and

  17. Determination of sulfadiazine in phosphate- and DOC-rich agricultural drainage water using solid-phase extraction followed by liquid chromatography-tandem mass spectrometry

    DEFF Research Database (Denmark)

    Bouyou, P.A. Léon; Weisser, Johan Juhl; Strobel, Bjarne W.

    2014-01-01

    % (relative standard deviation 15 %), while at 10 ng/L, it showed a lower recovery of 32 % (relative standard deviation 47 %). The final SPE LC-MS/MS method had a limit of detection (LOD)Method and a limit of quantification (LOQ)Method of 7.5 and 23 ng/L agricultural drainage water, respectively....... Determination of SDZ, spiked at a realistic concentration of 50 μg/L, in artificial drainage water (ADW) containing common and high levels of phosphate (0.05, 0.5, and 5 mg/L) gave recoveries between 70 and 92 % (relative standard deviation 7.4–12.9 %). Analysis of the same realistic concentration of SDZ in ADW...... obtained ranged from 104 to 109 % (relative standard deviation 2.8–5.2 %). The new methods enable determination of the veterinary antibiotic compound SDZ in agricultural drainage water from field experiments and monitoring schemes for phosphate- and dissolved organic carbon (DOC)-rich water samples...

  18. Cost-effectiveness analysis of surface flow constructed wetlands (SFCW) for nutrient reduction in drainage discharge from agricultural fields in Denmark

    DEFF Research Database (Denmark)

    Gachango, Florence Gathoni; Pedersen, Søren Marcus; Kjærgaard, Charlotte

    2015-01-01

    Constructed wetlands have been proposed as cost-effective and more targeted technologies in the reduction of nitrogen and phosphorous water pollution in drainage losses from agricultural fields in Denmark. Using two pig farms and one dairy farm situated in a pumped lowland catchment as case studies......, this paper explores the feasibility of implementing surface flow constructed wetlands (SFCW) based on their cost effectiveness. Sensitivity analysis is conducted by varying the cost elements of the wetlands in order to establish the most cost-effective scenario and a comparison with the existing nutrients...... reduction measures carried out. The analyses show that the cost effectiveness of the SFCW is higher in the drainage catchments with higher nutrient loads. The range of the cost effectiveness ratio on nitrogen reduction differs distinctively with that of catch crop measure. The study concludes that SFCW...

  19. El-Salam canal is a potential project reusing the Nile Delta drainage water for Sinai desert agriculture: Microbial and chemical water quality

    Directory of Open Access Journals (Sweden)

    Amal A. Othman

    2012-04-01

    Full Text Available More than 12 × 109 m3/year of Nile Delta drainage water is annually discharged into the Mediterranean Sea. El-Salam (peace canal, having a mixture of such drainage water and the Nile water (1:1 ratio, crosses the Suez canal eastward to the deserts of north Sinai. The suitability of the canal water for agriculture is reported here. Representative samples were obtained during two successive years to follow effects of seasonal and spatial distribution, along the first 55 km course in north Sinai, on the water load of total bacteria, bacterial indicators of pollution, and chemical and heavy metals contents. In general, the canal water is acceptable for irrigation, with much concern directed towards the chemical contents of total salts (EC, Na and K, as well as the trace elements Cd and Fe. Extending the canal course further than 30 km significantly lowered the fecal pollution rate to the permissible levels of drinking water. Results strongly emphasize the need for effective pre-treatment of the used drainage water resources prior mixing with the Nile water.

  20. Vegetated Ditches for the Mitigation of Pesticides Runoff in the Po Valley.

    Science.gov (United States)

    Otto, Stefan; Pappalardo, Salvatore E; Cardinali, Alessandra; Masin, Roberta; Zanin, Giuseppe; Borin, Maurizio

    2016-01-01

    In intensive agricultural systems runoff is one of the major potential diffuse pollution pathways for pesticides and poses a risk to surface water. Ditches are common in the Po Valley and can potentially provide runoff mitigation for the protection of watercourses. The effectiveness depends on ditch characteristics, so there is an urgent need for site-specific field trials. The use of a fugacity model (multimedia model) can allows recognition of the mitigation main processes. A field experiment was conducted in order to evaluate the mitigation capacity of a typical vegetated ditch, and results were compared with predictions by a fugacity model. To evaluate herbicide mitigation after an extreme runoff, the ditch was flooded with water containing mesotrione, S-metolachlor and terbuthylazine. Two other subsequent floods with uncontaminated water were applied 27 and 82 days later to evaluate herbicides release. Results show that the ditch can immediately reduce runoff concentration of herbicides by at least 50% even in extreme flooding conditions. The half-distances were about 250 m. As a general rule, a runoff of 1 mm from 5 ha is mitigated by 99% in 100 m of vegetated ditch. Herbicides retention in the vegetated ditch was reversible, and the second flood mobilized 0.03-0.2% of the previous one, with a concentration below the drinking water limit of 0.1 μg L(-1). No herbicide was detected in the third flood, because the residual amount in the ditch was too low. Fugacity model results show that specific physical-chemical parameters may be used and a specific soil-sediment-plant compartment included for modelling herbicides behaviour in a vegetated ditch, and confirm that accumulation is low or negligible for herbicides with a half-life of 40 days or less. Shallow vegetated ditches can thus be included in a general agri-environment scheme for the mitigation of pesticides runoff together with wetlands and linear buffer strips. These structures are present in the

  1. Vegetated Ditches for the Mitigation of Pesticides Runoff in the Po Valley.

    Directory of Open Access Journals (Sweden)

    Stefan Otto

    Full Text Available In intensive agricultural systems runoff is one of the major potential diffuse pollution pathways for pesticides and poses a risk to surface water. Ditches are common in the Po Valley and can potentially provide runoff mitigation for the protection of watercourses. The effectiveness depends on ditch characteristics, so there is an urgent need for site-specific field trials. The use of a fugacity model (multimedia model can allows recognition of the mitigation main processes. A field experiment was conducted in order to evaluate the mitigation capacity of a typical vegetated ditch, and results were compared with predictions by a fugacity model. To evaluate herbicide mitigation after an extreme runoff, the ditch was flooded with water containing mesotrione, S-metolachlor and terbuthylazine. Two other subsequent floods with uncontaminated water were applied 27 and 82 days later to evaluate herbicides release. Results show that the ditch can immediately reduce runoff concentration of herbicides by at least 50% even in extreme flooding conditions. The half-distances were about 250 m. As a general rule, a runoff of 1 mm from 5 ha is mitigated by 99% in 100 m of vegetated ditch. Herbicides retention in the vegetated ditch was reversible, and the second flood mobilized 0.03-0.2% of the previous one, with a concentration below the drinking water limit of 0.1 μg L(-1. No herbicide was detected in the third flood, because the residual amount in the ditch was too low. Fugacity model results show that specific physical-chemical parameters may be used and a specific soil-sediment-plant compartment included for modelling herbicides behaviour in a vegetated ditch, and confirm that accumulation is low or negligible for herbicides with a half-life of 40 days or less. Shallow vegetated ditches can thus be included in a general agri-environment scheme for the mitigation of pesticides runoff together with wetlands and linear buffer strips. These structures are

  2. Information technology and innovative drainage management practices for selenium load reduction from irrigated agriculture to provide stakeholder assurances and meet contaminant mass loading policy objectives

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, N.W.T.

    2009-10-15

    Many perceive the implementation of environmental regulatory policy, especially concerning non-point source pollution from irrigated agriculture, as being less efficient in the United States than in many other countries. This is partly a result of the stakeholder involvement process but is also a reflection of the inability to make effective use of Environmental Decision Support Systems (EDSS) to facilitate technical information exchange with stakeholders and to provide a forum for innovative ideas for controlling non-point source pollutant loading. This paper describes one of the success stories where a standardized Environmental Protection Agency (EPA) methodology was modified to better suit regulation of a trace element in agricultural subsurface drainage and information technology was developed to help guide stakeholders, provide assurances to the public and encourage innovation while improving compliance with State water quality objectives. The geographic focus of the paper is the western San Joaquin Valley where, in 1985, evapoconcentration of selenium in agricultural subsurface drainage water, diverted into large ponds within a federal wildlife refuge, caused teratogenecity in waterfowl embryos and in other sensitive wildlife species. The fallout from this environmental disaster was a concerted attempt by State and Federal water agencies to regulate non-point source loads of the trace element selenium. The complexity of selenium hydrogeochemistry, the difficulty and expense of selenium concentration monitoring and political discord between agricultural and environmental interests created challenges to the regulation process. Innovative policy and institutional constructs, supported by environmental monitoring and the web-based data management and dissemination systems, provided essential decision support, created opportunities for adaptive management and ultimately contributed to project success. The paper provides a retrospective on the contentious planning

  3. Environmental Setting of the Sugar Creek and Leary Weber Ditch Basins, Indiana, 2002-04

    Science.gov (United States)

    Lathrop, Timothy R.

    2006-01-01

    The Leary Weber Ditch Basin is nested within the Sugar Creek Basin in central Indiana. These basins make up one of the five study sites in the Nation selected for the Agricultural Chemicals: Sources, Transport, and Fate topical study, a part of the U.S. Geological Survey’s National Water-Quality Assessment Program. In this topical study, identifying the natural factors and human influences affecting water quality in the Leary Weber Ditch and Sugar Creek Basins are the focus of the assessment. A detailed comparison between the environmental settings of these basins is presented. Specifics of the topical study design as implemented in the Leary Weber Ditch and Sugar Creek Basins are described.

  4. LONG TERM EFFECTS OF AMELIORATIVE WORKS ON SOME SOIL QUALITY PARAMETERS FROM BAIA –MOLDOVA EXPERIMENTAL AGRICULTURAL DRAINAGE FIELD

    Directory of Open Access Journals (Sweden)

    V. Moca

    2009-10-01

    Full Text Available The soil-climatic conditions from Baia Depression – the hydrographical basin from the extra-Carpathian area of the Moldova River - have frequently determined the presence, under different forms, intensities and periods, of temporary water excess from soil. The underground drainage, as a measure of water excess control, with stagnant character, caused mainly by rainfall amounts registered for 1-5 consecutive days, was firstly arranged in pilot-experimental fields during 1972-1978. We followed the behaviour in exploitation of underground drainage technical solutions, as concerns the functional efficiency of the means of water excess removal and of the improved soil favourableness and/or suitability for crop growing.In order to assess the long-term effects of ameliorating works, applied in 1978 in the drainage field of Baia, on an area of 3.50 ha, we have qualitatively classified and estimated the albic stagnic glossic Luvosoil (S.R.T.S. – 2003, improved and unimproved. Based on this study, we have estimated the present favourableness for crops of the improved soil, as compared to unimproved soil, used as natural grassland, after an exploitation cycle of 30 years (1978- 2008.

  5. Investigating summer flow paths in a Dutch agricultural field using high frequency direct measurements

    Science.gov (United States)

    Delsman, J. R.; Waterloo, M. J.; Groen, M. M. A.; Groen, J.; Stuyfzand, P. J.

    2014-11-01

    The search for management strategies to cope with projected water scarcity and water quality deterioration calls for a better understanding of the complex interaction between groundwater and surface water in agricultural catchments. We separately measured flow routes to tile drains and an agricultural ditch in a deep polder in the coastal region of the Netherlands, characterized by exfiltration of brackish regional groundwater flow and intake of diverted river water for irrigation and water quality improvement purposes. We simultaneously measured discharge, electrical conductivity and temperature of these separate flow routes at hourly frequencies, disclosing the complex and time-varying patterns and origins of tile drain and ditch exfiltration. Tile drainage could be characterized as a shallow flow system, showing a non-linear response to groundwater level changes. Tile drainage was fed primarily by meteoric water, but still transported the majority (80%) of groundwater-derived salt to surface water. In contrast, deep brackish groundwater exfiltrating directly in the ditch responded linearly to groundwater level variations and is part of a regional groundwater flow system. We could explain the observed salinity of exfiltrating drain and ditch water from the interaction between the fast-responding pressure distribution in the subsurface that determined groundwater flow paths (wave celerity), and the slow-responding groundwater salinity distribution (water velocity). We found water demand for maintaining water levels and diluting salinity through flushing to greatly exceed the actual sprinkling demand. Counterintuitively, flushing demand was found to be largest during precipitation events, suggesting the possibility of water savings by operational flushing control.

  6. Humans reclaimed lands in NorthEastern Italy and artificial drainage networks: effects of 30 years of Agricultural Surface Water Management

    Science.gov (United States)

    Sofia, Giulia; Pizzulli, Federica; Tarolli, Paolo

    2017-04-01

    Agriculture and land-use management has changed drastically in Italy since the end of the Second World War, driven by local but also European agricultural policies. As a result of these changes in farming practices and land use, many drainage networks have changed producing a greater exposure to flooding with a broad range of impacts on society, also because of climate inputs coupling with the human drivers. This study focuses on two main points: which kind of land use and farming changes have been observed in the most recent years ( 30 years)? How do these changes interact with climate and soil conditions? An open challenge to understand how these changes influence the watershed response, is, in fact, to understand if rainfall characteristics and climate have a synergistic effect, if their interaction matters, or to understand what element has the greatest influence on the watershed response connected to agricultural changes. The work is based on a simple model of water infiltration due to soil properties, and a connected evaluation of the distributed surface water storage offered by artificial drainage networks in a study area in Veneto (north-eastern Italy). The analysis shows that economic changes control the development of agro-industrial landscapes, with effects on the hydrological response. However, these changes deeply interact with antecedent soil conditions and climate characteristics. Intense and irregular rainfall events and events with a high recurrence should be expected to be the most critical. The presented outcomes highlight the importance of understanding how agricultural practices can be the driver of or can be used to avoid, or at least mitigate, flooding. The proposed methods can be valuable tools in evaluating the costs and benefits of the management of water in agriculture to inform better policy decision-making. References Sofia G, Tarolli P. 2017. Hydrological Response to 30 years of Agricultural Surface Water Management. Land 6 (1): 3 DOI

  7. The impact of informal irrigation practices on soil drainage condition, soil pollution and land suitability for agriculture in El Saf area of El Giza Governorate

    Directory of Open Access Journals (Sweden)

    Hanan E.M. El Azab

    2015-12-01

    Full Text Available The study area was selected in El Saf District of El Giza Governorate in Egypt, covering 21461.4 ha of Nile sediments and their outskirts of alluvial higher and lower terraces. The aim of this study was to assess the impact of informal irrigation practices on drainage deterioration, soil pollution and land suitability for agricultural use using the satellite LDCM data 2013. From the lower alluvial terraces (partly cultivated using wastewater, the drainage flows westward via descending slopes resulting in land deterioration in both the alluvial lower terraces and alluvial plain of River Nile. The drainage conditions are excessively drained soils in the alluvial upper terraces within soils of Typic Haplocalcids, sandy skeletal, but in the lower terraces it partly occurred within soils of Typic Torriorthents, sandy skeletal. Moderately well drained soils occurred in soils of Typic Torriorthents, sandy in the alluvial lower terraces, while in the alluvial plain of Nile sediments are Sodic Haplotorrerts, fine. Poorly drained soils in the lower alluvial terraces have soils of Typic Epiaquents, sandy associated with Sodic Psammaquents and Aquic Haplocalcids, coarse loamy, while in the alluvial plain of River Nile the soils are Halic Epiaquerts, fine. Very poorly drained soils (submerged areas are scattered spots in both the lower alluvial terraces and the alluvial plain. In the alluvial plain of River Nile, 1967.1 ha become not suitable for the traditional cultivated crops, while in the alluvial terraces 3251.0 ha are not suitable for the proposed cultivation of Jojoba plants. Heavy metals of Cadmium (Cd, Cobalt (Co, Lead (Pb and Nickel (Ni were added to the soil surface and sub-surface in the irrigated areas by wastewater in the lower alluvial terraces (moderately well drained soils, but Cd and Co exceeded the standards of permissible total concentrations in these soils. The same metals were added to soil sub-surface layers in the alluvial plain

  8. Long-term monitoring of waterborne pathogens and microbial source tracking markers in paired agricultural watersheds under controlled and conventional tile drainage management.

    Science.gov (United States)

    Wilkes, Graham; Brassard, Julie; Edge, Thomas A; Gannon, Victor; Gottschall, Natalie; Jokinen, Cassandra C; Jones, Tineke H; Khan, Izhar U H; Marti, Romain; Sunohara, Mark D; Topp, Edward; Lapen, David R

    2014-06-01

    Surface waters from paired agricultural watersheds under controlled tile drainage (CTD) and uncontrolled tile drainage (UCTD) were monitored over 7 years in order to determine if there was an effect of CTD (imposed during the growing season) on occurrences and loadings of bacterial and viral pathogens, coliphages, and microbial source tracking markers. There were significantly lower occurrences of human, ruminant, and livestock (ruminant plus pig) Bacteroidales markers in the CTD watershed in relation to the UCTD watershed. As for pathogens, there were significantly lower occurrences of Salmonella spp. and Arcobacter spp. in the CTD watershed. There were no instances where there were significantly higher quantitative loadings of any microbial target in the CTD watershed, except for F-specific DNA (F-DNA) and F-RNA coliphages, perhaps as a result of fecal inputs from a hobby farm independent of the drainage practice treatments. There was lower loading of the ruminant marker in the CTD watershed in relation to the UCTD system, and results were significant at the level P = 0.06. The odds of Salmonella spp. occurring increased when a ruminant marker was present relative to when the ruminant marker was absent, yet for Arcobacter spp., the odds of this pathogen occurring significantly decreased when a ruminant marker was present relative to when the ruminant marker was absent (but increased when a wildlife marker was present relative to when the wildlife marker was absent). Interestingly, the odds of norovirus GII (associated with human and swine) occurring in water increased significantly when a ruminant marker was present relative to when a ruminant marker was absent. Overall, this study suggests that fecal pollution from tile-drained fields to stream could be reduced by CTD utilization. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  9. Long-Term Monitoring of Waterborne Pathogens and Microbial Source Tracking Markers in Paired Agricultural Watersheds under Controlled and Conventional Tile Drainage Management

    Science.gov (United States)

    Wilkes, Graham; Brassard, Julie; Edge, Thomas A.; Gannon, Victor; Gottschall, Natalie; Jokinen, Cassandra C.; Jones, Tineke H.; Khan, Izhar U. H.; Marti, Romain; Sunohara, Mark D.; Topp, Edward

    2014-01-01

    Surface waters from paired agricultural watersheds under controlled tile drainage (CTD) and uncontrolled tile drainage (UCTD) were monitored over 7 years in order to determine if there was an effect of CTD (imposed during the growing season) on occurrences and loadings of bacterial and viral pathogens, coliphages, and microbial source tracking markers. There were significantly lower occurrences of human, ruminant, and livestock (ruminant plus pig) Bacteroidales markers in the CTD watershed in relation to the UCTD watershed. As for pathogens, there were significantly lower occurrences of Salmonella spp. and Arcobacter spp. in the CTD watershed. There were no instances where there were significantly higher quantitative loadings of any microbial target in the CTD watershed, except for F-specific DNA (F-DNA) and F-RNA coliphages, perhaps as a result of fecal inputs from a hobby farm independent of the drainage practice treatments. There was lower loading of the ruminant marker in the CTD watershed in relation to the UCTD system, and results were significant at the level P = 0.06. The odds of Salmonella spp. occurring increased when a ruminant marker was present relative to when the ruminant marker was absent, yet for Arcobacter spp., the odds of this pathogen occurring significantly decreased when a ruminant marker was present relative to when the ruminant marker was absent (but increased when a wildlife marker was present relative to when the wildlife marker was absent). Interestingly, the odds of norovirus GII (associated with human and swine) occurring in water increased significantly when a ruminant marker was present relative to when a ruminant marker was absent. Overall, this study suggests that fecal pollution from tile-drained fields to stream could be reduced by CTD utilization. PMID:24727274

  10. Agriculture

    International Nuclear Information System (INIS)

    Goetz, B.; Riss, A.; Zethner, G.

    2001-01-01

    This chapter deals with fertilization techniques, bioenergy from agriculture, environmental aspects of a common agriculture policy in the European Union, bio-agriculture, fruit farming in Austria and with environmental indicators in agriculture. In particular renewable energy sources (bio-diesel, biogas) from agriculture are studied in comparison to fossil fuels and other energy sources. (a.n.)

  11. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Artificial Drainage (1992) and Irrigation (1997)

    Science.gov (United States)

    Wieczorek, Michael; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the estimated area of artifical drainage for the year 1992 and irrigation types for the year 1997 compiled for every MRB_E2RF1 catchment of Major River Basins (MRBs, Crawford and others, 2006). The source data sets were derived from tabular National Resource Inventory (NRI) data sets created by the National Resources Conservation Service (NRCS, U.S. Department of Agriculture, 1995, 2000). Artificial drainage is defined as subsurface drains and ditches. Irrigation types are defined as gravity and pressure. Subsurface drains are described as conduits, such as corrugated plastic tubing, tile, or pipe, installed beneath the ground surface to collect and/or convey drainage. Surface drainage field ditches are described as graded ditches for collecting excess water. Gravity irrigation source is described as irrigation delivered to the farm and/or field by canals or pipelines open to the atmosphere; and water is distributed by the force of gravity down the field by: (1) A surface irrigation system (border, basin, furrow, corrugation, wild flooding, etc.) or (2) Sub-surface irrigation pipelines or ditches. Pressure irrigation source is described as irrigation delivered to the farm and/or field in pump or elevation-induced pressure pipelines, and water is distributed across the field by: (1) Sprinkle irrigation (center pivot, linear move, traveling gun, side roll, hand move, big gun, or fixed set sprinklers), or (2) Micro irrigation (drip emitters, continuous tube bubblers, micro spray or micro sprinklers). NRI data do not include Federal lands and are thus excluded from this dataset. The tabular data for drainage were spatially apportioned to the National Land Cover Dataset (NLCD, Kerie Hitt, U.S. Geological Survey, written commun., 2005) and the tabular data for irrigation were spatially apportioned to an enhanced version of the National Land Cover Dataset (NLCDe, Nakagaki and others, 2007). The MRB_E2RF1 catchments are based on a modified

  12. 14 CFR 25.1415 - Ditching equipment.

    Science.gov (United States)

    2010-01-01

    ... operating rules of this chapter, must meet the requirements of this section. (b) Each liferaft and each life... liferaft. (d) There must be an approved survival type emergency locator transmitter for use in one life raft. (e) For airplanes not certificated for ditching under § 25.801 and not having approved life...

  13. 14 CFR 27.801 - Ditching.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ditching. 27.801 Section 27.801 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 27.801...

  14. 14 CFR 29.801 - Ditching.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Ditching. 29.801 Section 29.801 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Personnel and Cargo Accommodations § 29.801...

  15. South Carolina's best management practices for forestry for minor drainage

    Science.gov (United States)

    Tonya Smith; Herb Nicholson

    2016-01-01

    Minor drainage is normally used to facilitate regeneration and timber harvesting by temporarily removing surface water from inundated forestland. Specific ditch depth and spacing recommendations are not listed in our manual, as each site is individually evaluated.

  16. Effects of peatland drainage management on peak flows

    OpenAIRE

    C. E. Ballard; N. McIntyre; H. S. Wheater

    2011-01-01

    Open ditch drainage has historically been a common land management practice in upland blanket peats, particularly in the UK. However, peatland drainage is now generally considered to have adverse effects on the upland environment, including increased peak flows. As a result, drain blocking has become a common management strategy in the UK over recent years, although there is only anecdotal evidence to suggest that this might decrease peak flows. The change in the hydrologica...

  17. Agriculture

    Science.gov (United States)

    The EPA Agriculture Resource Directory offers comprehensive, easy-to-understand information about environmental stewardship on farms and ranches; commonsense, flexible approaches that are both environmentally protective and agriculturally sound.

  18. Plant distribution patterns related to species characteristics and spatial and temporal habitat heterogeneity in a network of ditch banks

    NARCIS (Netherlands)

    Geertsema, W.; Sprangers, J.T.C.M.

    2002-01-01

    In this study we investigated the relationship between the distribution patterns of a number of herbaceous plant species and the isolation and age of habitat patches. The study was conducted for a network of ditch banks in an agricultural landscape in The Netherlands. Thirteen plant species were

  19. The strategies of local farmers' water management and the eco-hydrological effects of irrigation-drainage engineering systems in world heritage of Honghe Hani Rice Terraces

    Science.gov (United States)

    Gao, Xuan

    2017-04-01

    Terraces are built in mountainous regions to provide larger area for cultivation,in which the hydrological and geomorphological processes are impacted by local farmers' water management strategies and are modified by manmade irrigation-drainage engineering systems.The Honghe Hani Rice Terraces is a 1300a history of traditional agricultural landscape that was inscribed in the 2013 World Heritage List.The local farmers had developed systematic water management strategies and built perfect irrigation-drainage engineering systems to adapt the local rainfall pattern and rice farming activities.Through field investigation,interviews,combined with Geographic Information Systems,Remote Sensing images and Global Positioning Systems technology,the water management strategies as well as the irrigation-drainage systems and their impacts on eco-hydrological process were studied,the results indicate:Firstly,the local people created and maintained an unique woodcarving allocating management system of irrigating water over hundreds years,which aids distributing water and natural nutrition to each terrace field evenly,and regularly according to cultivation schedule.Secondly,the management of local people play an essential role in effective irrigation-drainage engineering system.A ditch leader takes charge of managing the ditch of their village,keeping ample amount of irrigation water,repairing broken parts of ditches,dealing with unfair water using issues,and so on.Meanwhile,some traditional leaders of minority also take part in.Thus, this traditional way of irrigation-drainage engineering has bringed Hani people around 1300 years of rice harvest for its eco-hydrological effects.Lastly we discuss the future of Honghe Hani Rice Terraces,the traditional cultivation pattern has been influenced by the rapid development of modern civilization,in which some related changes such as the new equipment of county roads and plastic channels and the water overusing by tourism are not totally

  20. Vegetated Treatment Systems for Removing Contaminants Associated with Surface Water Toxicity in Agriculture and Urban Runoff.

    Science.gov (United States)

    Anderson, Brian S; Phillips, Bryn M; Voorhees, Jennifer P; Cahn, Michael

    2017-05-15

    Urban stormwater and agriculture irrigation runoff contain a complex mixture of contaminants that are often toxic to adjacent receiving waters. Runoff may be treated with simple systems designed to promote sorption of contaminants to vegetation and soils and promote infiltration. Two example systems are described: a bioswale treatment system for urban stormwater treatment, and a vegetated drainage ditch for treating agriculture irrigation runoff. Both have similar attributes that reduce contaminant loading in runoff: vegetation that results in sorption of the contaminants to the soil and plant surfaces, and water infiltration. These systems may also include the integration of granulated activated carbon as a polishing step to remove residual contaminants. Implementation of these systems in agriculture and urban watersheds requires system monitoring to verify treatment efficacy. This includes chemical monitoring for specific contaminants responsible for toxicity. The current paper emphasizes monitoring of current use pesticides since these are responsible for surface water toxicity to aquatic invertebrates.

  1. Applications of network analysis for adaptive management of artificial drainage systems in landscapes vulnerable to sea level rise

    Science.gov (United States)

    Poulter, Benjamin; Goodall, Jonathan L.; Halpin, Patrick N.

    2008-08-01

    SummaryThe vulnerability of coastal landscapes to sea level rise is compounded by the existence of extensive artificial drainage networks initially built to lower water tables for agriculture, forestry, and human settlements. These drainage networks are found in landscapes with little topographic relief where channel flow is characterized by bi-directional movement across multiple time-scales and related to precipitation, wind, and tidal patterns. The current configuration of many artificial drainage networks exacerbates impacts associated with sea level rise such as salt-intrusion and increased flooding. This suggests that in the short-term, drainage networks might be managed to mitigate sea level rise related impacts. The challenge, however, is that hydrologic processes in regions where channel flow direction is weakly related to slope and topography require extensive parameterization for numerical models which is limited where network size is on the order of a hundred or more kilometers in total length. Here we present an application of graph theoretic algorithms to efficiently investigate network properties relevant to the management of a large artificial drainage system in coastal North Carolina, USA. We created a digital network model representing the observation network topology and four types of drainage features (canal, collector and field ditches, and streams). We applied betweenness-centrality concepts (using Dijkstra's shortest path algorithm) to determine major hydrologic flowpaths based off of hydraulic resistance. Following this, we identified sub-networks that could be managed independently using a community structure and modularity approach. Lastly, a betweenness-centrality algorithm was applied to identify major shoreline entry points to the network that disproportionately control water movement in and out of the network. We demonstrate that graph theory can be applied to solving management and monitoring problems associated with sea level rise

  2. Agriculture

    International Nuclear Information System (INIS)

    2002-01-01

    The report entitled Climate Change Impacts and Adaptation : A Canadian Perspective, presents a summary of research regarding the impacts of climate change on key sectors over the past five years as it relates to Canada. This chapter on agriculture describes how climate change will affect primary agriculture production in Canada with particular focus on potential adaptation options, and vulnerability of agriculture at the farm level. Agriculture is a vital part of the Canadian economy, although only 7 per cent of Canada's land mass is used for agricultural purposes due to the limitations of climate and soils. Most parts of Canada are expected to experience warmer conditions, longer frost-free seasons and increased evapotranspiration. The impacts of these changes on agriculture will vary depending on precipitation changes, soil conditions, and land use. Northern regions may benefit from longer farming seasons, but poor soil conditions will limit the northward expansion of agricultural crops. Some of the negative impacts associated with climate change on agriculture include increased droughts, changes in pest and pathogen outbreaks, and moisture stress. In general, it is expected that the positive and negative impacts of climate change would offset each other. 74 refs., 2 tabs., 1 fig

  3. Pedo-sedimentary record of human-environment interaction in ditches and waterlogged depressions on tableland (roman and early medieval period) : micromorphological cases studies from Marne-la-Vallée area (Paris Basin, France)

    Science.gov (United States)

    Cammas, C.; Blanchard, J.; Broutin, P.; Berga, A.

    2012-04-01

    On lœss derived soils located on the Stampien plateau from the Paris Basin (France), archaeological anthroposols and ancient cultivated soils are only preserved in very few places. Recent archaeological excavations showed the presence of a pattern of roman ditches and waterlogged depressions (« mares ») under the actual cultivated horizon (Ap). This presence strongly suggests extensive past agricultural practices and water management. An original system of ditches was found Near Marne-la-Vallée (France). It is composed of two parts, one being large ditches characterized by flat bottom and sometimes water layered deposits, called « fossés collecteurs » by the archaeologists, and the orher being smaller ditches with colluvial deposits. Our objectives was to use archaeological and micromorphological studies in order to study i) the agricultural function of these ditches and depressions, ii) their evolution with time. Observations conducted on the infilling of a « fossé collecteur » at Bussy-Saint-Georges suggest that it was not part of a drainage system, but that it was a linear water controlled system, with a ramp in one part, and a basin or a tank in another, and that it was used for others anthropic activities. In the same area, a large waterlogged depression was studied, and micromorphological analysis helped to elucidate its pedo-sedimentary formation processes. At the bottom, massive silty clayey matrix retained water. Thin layers composed of silt and clay (indicating low energy flows and decantation), sometimes impregnated and hardened by iron, alternated with silty deposit (indicating higher ernergy water layered deposits). The thin, non porous and iron impregnated crusts helped to raise the depression level, as well as, most likely the water table during roman period, maintaining waterlogging conditions. At the beginning of the early medival period, a slightly peaty event was discriminated. Higher in the profile, in more redoxic conditions

  4. High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

    Science.gov (United States)

    Rozemeijer, J. C.; Visser, A.; Borren, W.; Winegram, M.; van der Velde, Y.; Klein, J.; Broers, H. P.

    2016-01-01

    High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an effective option to optimize soil moisture conditions for agriculture and to reduce unnecessary losses of fresh water and nutrients. This is achieved by introducing control structures with adjustable overflow levels into subsurface tube drain systems. A small-scale (1 ha) field experiment was designed to investigate the hydrological and chemical changes after introducing controlled drainage. Precipitation rates and the response of water tables and drain fluxes were measured in the periods before the introduction of controlled drainage (2007-2008) and after (2009-2011). For the N and P concentration measurements, auto-analyzers for continuous records were combined with passive samplers for time-averaged concentrations at individual drain outlets. The experimental setup enabled the quantification of changes in the water and solute balance after introducing controlled drainage. The results showed that introducing controlled drainage reduced the drain discharge and increased the groundwater storage in the field. To achieve this, the overflow levels have to be elevated in early spring, before the drain discharge stops due to dryer conditions and falling groundwater levels. The groundwater storage in the field would have been larger if the water levels in the adjacent ditch were controlled as well by an adjustable weir. The N concentrations and loads increased, which was largely related to elevated concentrations in one of the three monitored tube drains. The P loads via the tube drains reduced due to the reduction in discharge after introducing controlled drainage. However, this may be counteracted by the higher groundwater levels and the larger contribution of N- and P

  5. Polybrominated diphenyl ethers, perfluorinated alkylated substances, and metals in tile drainage and groundwater following applications of municipal biosolids to agricultural fields.

    Science.gov (United States)

    Gottschall, N; Topp, E; Edwards, M; Russell, P; Payne, M; Kleywegt, S; Curnoe, W; Lapen, D R

    2010-01-15

    Polybrominated diphenyl ethers (PBDEs), perfluorinated alkylated substances (PFAS), and metals were monitored in tile drainage and groundwater following liquid (LMB) and dewatered municipal biosolid (DMB) applications to silty-clay loam agricultural field plots. LMB was applied (93,500 L ha(-1)) in late fall 2005 via surface spreading on un-tilled soil (SS(LMB)), and a one-pass aerator-based pre-tillage prior to surface spreading (AerWay SSD) (A). The DMB was applied (8 Mg d wha(-1)) in early summer 2006 on the same plots by injecting DMB beneath the soil surface (DI), and surface spreading on un-tilled soil (SS(DMB)). Key PBDE congeners (BDE-47, -99, -100, -153, -154, -183, -209) comprising 97% of total PBDE in LMB, had maximum tile effluent concentrations ranging from 6 to 320 ng L(-1) during application-induced tile flow. SS(LMB) application-induced tile mass loads for these PBDE congeners were significantly higher than those for control (C) plots (no LMB) (p0.05). PBDE mass loss via tile (0-2h post-application) as a percent of mass applied was approximately 0.04-0.1% and approximately 0.8-1.7% for A and SS(LMB), respectively. Total PBDE loading to soil via LMB and DMB application was 0.0018 and 0.02 kg total PBDE ha(-1)yr(-1), respectively. Total PBDE concentration in soil (0-0.2m) after both applications was 115 ng g(-1)dw, (sampled 599 days and 340 days post LMB and DMB applications respectively). Of all the PFAS compounds, only PFOS (max concentration=17 ng L(-1)) and PFOA (12 ng L(-1)) were found above detectable limits in tile drainage from the application plots. Mass loads of metals in tile for the LMB application-induced tile hydrograph event, and post-application concentrations of metals in groundwater, showed significant (pA>C for tile and SS(LMB) and A>C for groundwater for most results). Following DMB application, no significant differences in metal mass loads in tile were found between SS(DMB) and DI treatments (PBDE/PFAS were not measured). But for

  6. Managing Artificially Drained Low-Gradient Agricultural Headwaters for Enhanced Ecosystem Functions

    Science.gov (United States)

    Pierce, Samuel C.; Kröger, Robert; Pezeshki, Reza

    2012-01-01

    Large tracts of lowlands have been drained to expand extensive agriculture into areas that were historically categorized as wasteland. This expansion in agriculture necessarily coincided with changes in ecosystem structure, biodiversity, and nutrient cycling. These changes have impacted not only the landscapes in which they occurred, but also larger water bodies receiving runoff from drained land. New approaches must append current efforts toward land conservation and restoration, as the continuing impacts to receiving waters is an issue of major environmental concern. One of these approaches is agricultural drainage management. This article reviews how this approach differs from traditional conservation efforts, the specific practices of drainage management and the current state of knowledge on the ecology of drainage ditches. A bottom-up approach is utilized, examining the effects of stochastic hydrology and anthropogenic disturbance on primary production and diversity of primary producers, with special regard given to how management can affect establishment of macrophytes and how macrophytes in agricultural landscapes alter their environment in ways that can serve to mitigate non-point source pollution and promote biodiversity in receiving waters. PMID:24832519

  7. Managing Artificially Drained Low-Gradient Agricultural Headwaters for Enhanced Ecosystem Functions

    Directory of Open Access Journals (Sweden)

    Reza Pezeshki

    2012-12-01

    Full Text Available Large tracts of lowlands have been drained to expand extensive agriculture into areas that were historically categorized as wasteland. This expansion in agriculture necessarily coincided with changes in ecosystem structure, biodiversity, and nutrient cycling. These changes have impacted not only the landscapes in which they occurred, but also larger water bodies receiving runoff from drained land. New approaches must append current efforts toward land conservation and restoration, as the continuing impacts to receiving waters is an issue of major environmental concern. One of these approaches is agricultural drainage management. This article reviews how this approach differs from traditional conservation efforts, the specific practices of drainage management and the current state of knowledge on the ecology of drainage ditches. A bottom-up approach is utilized, examining the effects of stochastic hydrology and anthropogenic disturbance on primary production and diversity of primary producers, with special regard given to how management can affect establishment of macrophytes and how macrophytes in agricultural landscapes alter their environment in ways that can serve to mitigate non-point source pollution and promote biodiversity in receiving waters.

  8. A synthesis of the impacts of ditch network maintenance on the quantity and quality of runoff from drained boreal peatland forests.

    Science.gov (United States)

    Nieminen, Mika; Palviainen, Marjo; Sarkkola, Sakari; Laurén, Ari; Marttila, Hannu; Finér, Leena

    2017-10-29

    Drained peatlands are an important source of forest biomass in boreal regions and ditch network maintenance (DNM) operations may be needed to restore the drainage functions of ditches. By reviewing the available literature, as well as utilizing an existing hydrological model and analyzing the characteristics of eroded sediments, we assessed the impacts of DNM on runoff and exports of suspended solids (SS), dissolved organic carbon (DOC), nitrogen (N), and phosphorus (P). In general, DNM had minor impact on runoff and dissolved N and P, and it decreased rather than increased DOC exports. To increase the understanding of the hydrochemical impacts of DNM, future research should focus on the characteristics of SS and particulate nutrient exports. A major gap in knowledge is also the very limited regional representativeness of the available studies. High erosion risk in the ditches reaching the mineral soil below peat should be acknowledged when planning mitigation measures.

  9. Pharmaceutical and personal care products in tile drainage following surface spreading and injection of dewatered municipal biosolids to an agricultural field.

    Science.gov (United States)

    Edwards, M; Topp, E; Metcalfe, C D; Li, H; Gottschall, N; Bolton, P; Curnoe, W; Payne, M; Beck, A; Kleywegt, S; Lapen, D R

    2009-07-01

    Land application of municipal biosolids can be a source of environmental contamination by pharmaceutical and personal care products (PPCPs). This study examined PPCP concentrations/temporally discrete mass loads in agricultural tile drainage systems where two applications of biosolids had previously taken place. The field plots received liquid municipal biosolids (LMB) in the fall of 2005 at an application rate of approximately 93,500 L ha (-1), and a second land application was conducted using dewatered municipal biosolids (DMB) applied at a rate of approximately 8Mg dw ha (-1) in the summer of 2006 [corrected].The DMB land application treatments consisted of direct injection (DI) of the DMB beneath the soil surface at a nominal depth of approximately 0.11 m, and surface spreading (SS) plus subsequent tillage incorporation of DMB in the topsoil (approximately 0.10 m depth). The PPCPs examined included eight pharmaceuticals (acetaminophen, fluoxetine, ibuprofen, gemfibrozil, naproxen, carbamazepine, atenolol, sulfamethoxazole), the nicotine metabolite cotinine, and two antibacterial personal care products triclosan and triclocarban. Residues of naproxen, cotinine, atenolol and triclosan originating from the fall 2005 LMB application were detected in tile water nearly nine months after application (triclocarban was not measured in 2005). There were no significant differences (p>0.05) in PPCP mass loads among the two DMB land application treatments (i.e., SS vs. DI); although, average PPCP mass loads late in the study season (>100 days after application) were consistently higher for the DI treatment relative to the SS treatment. While the concentration of triclosan (approximately 14,000 ng g(-1) dw) in DMB was about twice that of triclocarban (approximately 8000 ng g(-1) dw), the average tile water concentrations for triclosan were much higher (43+/-5 ng L(-1)) than they were for triclocarban (0.73+/-0.14 ng L(-1)). Triclosan concentrations (maximum observed in 2006

  10. SCIENTIFIC SUPPORT OF SURVEY, DESIGN, CONSTRUCTION AND OPERATION OF THE MOTHER OF GOD DITCH OF SERAPHIMO-DIVEEVSKY MONASTERY

    Directory of Open Access Journals (Sweden)

    Darchiya Valentina Ivanovna

    2018-02-01

    Full Text Available Subject: the article describes the structure, technologies of construction, gardening and exploitation of the Holy Trinity Seraphimo-Diveevsky Monastery - the ancient linear fortification consisting of a ditch and an earth embankment that is located directly above the ditch. Research objectives: ensure the stability of slopes, create a technique for gardening of steep slopes in difficult microclimatic conditions, ensure drainage of water. Materials and methods: the computational techniques were used to ensure stability of slopes, and experimental techniques were applied for their phyto-fixation; geosynthetics, rebar grids, varietal herbs, gooseberries and thuja were used. Results: for recreation of the unique structure, a special set of design, survey and construction works was developed, as well as works to maintain the structure during its exploitation. In particular, we have developed the method of detection of the recreated ditch based on the stratification of bulk soils by their age; the methods for fastening the slopes; lawn grass mixture formula for slopes with angles of 45° and 65°; drainage system. Conclusions: owing to the research work, for the first time this construction was completed with the required parameters, while the earlier recreation attempts failed due to erosion and landslide processes. The developed methods can be applied for recreation of other ancient defensive fortifications on the fields of great battles and for landscaping the territories with complex relief.

  11. Affordances of Ditches for Children in Preschool

    DEFF Research Database (Denmark)

    Lerstrup, Inger Elisabeth; Møller, Maja Steen

    2016-01-01

    This study aims to expand understanding of the affordances provided by ditches in a Danish preschool context. Affordances are defined as the meaningful action possibilities of the environment. At a forest preschool, a group of 21 children aged approximately 3to 6.5 years accompanied by two to three...... offered varied and changing action possibilities for the preschool children. The paper discusses the possible incorporation of this largely unrecognized design element by planners and managers of green spaces and playgrounds for children in preschool....

  12. Drainage in Shallow Peatlands of Marginal Upland Landscapes: DOC Losses from High Flow Events

    Science.gov (United States)

    Grand-Clement, E.; Anderson, K.; Luscombe, D.; Gatis, N.; Benaud, P.; Brazier, R.

    2013-12-01

    Peatlands are widely represented in northern Europe, especially in the UK. In the South West of England (i.e. Exmoor, Dartmoor and Bodmin moors), climate change puts their existence under threat: according to recent modelling work, marginal peatlands are highly vulnerable to future temperature and precipitation change and are likely to be the first to disappear from as early as 2050. Additionally, peat cutting and intensive drainage for agricultural reclamation in the 19th and 20th century, have modified the hydrological behaviour of these shallow peatlands and dried out the upper layers, causing oxidation, erosion and vegetation change. Such anthropogenic interventions directly impact on the storage of carbon, but also the provision of other ecosystem services, such as the supply of drinking water, and the support of specific and rare habitats. Large restoration programs involving the blocking of drainage ditches are currently under way throughout the UK but, to date, little is known about the consequences of such management approaches on overall Carbon stocks, and whether the restoration can revert ecosystems back to a state similar to that of undisturbed peatlands. In this context, Exmoor is particularly vulnerable due to its location at the southernmost margin of the UK peatlands' geographical extent, and its dense network of drainage ditches putting pressure on already very shallow peat resources. We hypothesise that monitoring of these peatlands may provide an ';early warning system' for climatic impacts that could affect more northerly sites in years to come, as climates change more significantly. The aim of this study is to look at the current impact of peatland degradation on water quality on Exmoor during rainfall-runoff events. Our experimental approach employs detailed, high resolution monitoring of selected ditches that are representative of damaged conditions on Exmoor, from small- (30 x 30cm ditches) through medium- (50x50cm), large- (1-2m ditches

  13. Effects of peatland drainage on water quality: a case study of the shallow blanket bogs of Exmoor, UK

    Science.gov (United States)

    Grand-Clement, E.; Luscombe, D.; Le Feuvre, N.; Smith, D.; Anderson, K.; Brazier, R. E.

    2012-04-01

    Peatlands are widely represented in the South West of England (i.e. Exmoor, Dartmoor and Bodmin moors), but their existence is currently under threat due to both climate change and the impact of historical human activities. Peat cutting and intensive drainage for agricultural reclamation in the 19th and 20th century, have modified the hydrological behaviour of these shallow peats and dried out the upper layers, causing oxidation, erosion and vegetation change. Such anthropogenic impacts directly affect the storage of carbon, but also the provision of other ecosystem services, such as the supply of drinking water, and the support of specific and rare habitats. Blocking drainage ditches to restore the hydrological behaviour of peatlands has mostly been undertaken in the North of England, but to date, little is still known about the consequences of such management approaches on the overall Carbon stocks. The need to monitor restoration of peatlands in the South West of England arises due to the specific characteristics of the peat - it is often shallower than more northerly peat and dominated by Purple Moor Grass. In addition, and in part because of the shallowness of the resource, the peat has been damaged differently, often with very dense networks of hand-cut ditches which behave as highly efficient drainage networks. Most importantly, their location at the southernmost margin of the UK peatlands' geographical extent makes them extremely vulnerable to climate change, and so it is hypothesised that monitoring of these peatlands may provide an 'early warning system' for climatic impacts that affect more northerly sites in years to come. This study focuses upon the current impact of peatland degradation on water quality on Exmoor. Our experimental approach employs detailed, high resolution monitoring of selected ditches that are representative of damaged conditions on Exmoor, from small- (30 x 30cm ditches) through medium- (50x50cm), large- (1-2m ditches) and finally

  14. Occurrence, distribution, and transport of pesticides in agricultural irrigation-return flow from four drainage basins in the Columbia Basin Project, Washington, 2002-04, and comparison with historical data

    Science.gov (United States)

    Wagner, Richard J.; Frans, Lonna M.; Huffman, Raegan L.

    2006-01-01

    Water-quality samples were collected from sites in four irrigation return-flow drainage basins in the Columbia Basin Project from July 2002 through October 2004. Ten samples were collected throughout the irrigation season (generally April through October) and two samples were collected during the non-irrigation season. Samples were analyzed for temperature, pH, specific conductance, dissolved oxygen, major ions, trace elements, nutrients, and a suite of 107 pesticides and pesticide metabolites (pesticide transformation products) and to document the occurrence, distribution, and pesticides transport and pesticide metabolites. The four drainage basins vary in size from 19 to 710 square miles. Percentage of agricultural cropland ranges from about 35 percent in Crab Creek drainage basin to a maximum of 75 percent in Lind Coulee drainage basin. More than 95 percent of cropland in Red Rock Coulee, Crab Creek, and Sand Hollow drainage basins is irrigated, whereas only 30 percent of cropland in Lind Coulee is irrigated. Forty-two pesticides and five metabolites were detected in samples from the four irrigation return-flow drainage basins. The most compounds detected were in samples from Sand Hollow with 37, followed by Lind Coulee with 33, Red Rock Coulee with 30, and Crab Creek with 28. Herbicides were the most frequently detected pesticides, followed by insecticides, metabolites, and fungicides. Atrazine, bentazon, diuron, and 2,4-D were the most frequently detected herbicides and chlorpyrifos and azinphos-methyl were the most frequently detected insecticides. A statistical comparison of pesticide concentrations in surface-water samples collected in the mid-1990s at Crab Creek and Sand Hollow with those collected in this study showed a statistically significant increase in concentrations for diuron and a statistically significant decrease for ethoprophos and atrazine in Crab Creek. Statistically significant increases were in concentrations of bromacil, diuron, and

  15. Modelling strategies for numerical simulation of aircraft ditching

    NARCIS (Netherlands)

    Bisagni, C.; Pigazzini, M. S.

    2017-01-01

    Ditching, which is a controlled landing of an airplane on water, is an emergency condition to be investigated in order to improve the aircraft global crashworthiness. The complex hydrodynamic phenomena involved in ditching events are difficult to simulate and the accuracy of the results depends

  16. Horizontal distribution of phosphorus in soils of irrigation ditches ...

    African Journals Online (AJOL)

    Horizontal distribution of phosphorus in soils of irrigation ditches. ... correlations were found between soil P and stream water P on one hand, and between soil pH and stream water pH on the other, indicating that the irrigation water may indeed, have had little or no influence on the properties of the ditches' soils.

  17. Effects of Bt-transgenic rice cultivation on planktonic communities in paddy fields and adjacent ditches

    International Nuclear Information System (INIS)

    Liu, Yongbo; Liu, Fang; Wang, Chao; Quan, Zhanjun; Li, Junsheng

    2016-01-01

    The non-target effects of transgenic plants are issues of concern; however, their impacts in cultivated agricultural fields and adjacent natural aquatic ecosystems are poorly understood. We conducted field experiments during two growing seasons to determine the effects of cultivating Bacillus thuringiensis (Bt)-transgenic rice on the phytoplankton and zooplankton communities in a paddy field and an adjacent ditch. Bt toxin was detected in soil but not in water. Water quality was not significantly different between non-Bt and Bt rice fields, but varied among up-, mid- and downstream locations in the ditch. Cultivation of Bt-transgenic rice had no effects on zooplankton communities. Phytoplankton abundance and biodiversity were not significantly different between transgenic and non-transgenic rice fields in 2013; however, phytoplankton were more abundant in the transgenic rice field than in the non-transgenic rice field in 2014. Water quality and rice type explained 65.9% and 12.8% of this difference in 2014, respectively. Phytoplankton and zooplankton were more abundant in mid- and downstream, than upstream, locations in the ditch, an effect that we attribute to water quality differences. Thus, the release of Bt toxins into field water during the cultivation of transgenic crops had no direct negative effects on plankton community composition, but indirect effects that alter environmental conditions should be taken into account during the processes of management planning and policymaking. - Highlights: • We detect fusion Cry1Ab/1Ac proteins from Bt rice entering into aquatic ecosystems. • Bt-transgenic rice cultivation have no significant effect on zooplankton community. • Bt-transgenic rice cultivation have indirect effect on phytoplankton community. • Water quality explains the difference of plankton communities in adjacent ditches.

  18. Effects of Bt-transgenic rice cultivation on planktonic communities in paddy fields and adjacent ditches

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yongbo, E-mail: liuyb@craes.org.cn [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Liu, Fang [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Wang, Chao [Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou 510380 (China); Quan, Zhanjun [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Li, Junsheng, E-mail: lijsh@creas.org.cn [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China)

    2016-09-15

    The non-target effects of transgenic plants are issues of concern; however, their impacts in cultivated agricultural fields and adjacent natural aquatic ecosystems are poorly understood. We conducted field experiments during two growing seasons to determine the effects of cultivating Bacillus thuringiensis (Bt)-transgenic rice on the phytoplankton and zooplankton communities in a paddy field and an adjacent ditch. Bt toxin was detected in soil but not in water. Water quality was not significantly different between non-Bt and Bt rice fields, but varied among up-, mid- and downstream locations in the ditch. Cultivation of Bt-transgenic rice had no effects on zooplankton communities. Phytoplankton abundance and biodiversity were not significantly different between transgenic and non-transgenic rice fields in 2013; however, phytoplankton were more abundant in the transgenic rice field than in the non-transgenic rice field in 2014. Water quality and rice type explained 65.9% and 12.8% of this difference in 2014, respectively. Phytoplankton and zooplankton were more abundant in mid- and downstream, than upstream, locations in the ditch, an effect that we attribute to water quality differences. Thus, the release of Bt toxins into field water during the cultivation of transgenic crops had no direct negative effects on plankton community composition, but indirect effects that alter environmental conditions should be taken into account during the processes of management planning and policymaking. - Highlights: • We detect fusion Cry1Ab/1Ac proteins from Bt rice entering into aquatic ecosystems. • Bt-transgenic rice cultivation have no significant effect on zooplankton community. • Bt-transgenic rice cultivation have indirect effect on phytoplankton community. • Water quality explains the difference of plankton communities in adjacent ditches.

  19. Sampling and Analysis Plan for the 216-A-29 Ditch

    International Nuclear Information System (INIS)

    Petersen, S.W.

    1998-06-01

    This sampling and analysis plan defines procedures to be used for collecting and handling samples to be obtained from the 216-A-29 Ditch, and identifies requirements for field and laboratory measurements. The sampling strategy describes here is derived from a Data Quality Objectives workshop conducted in January 1997 to support sampling to assure worker safety during construction and to assess the validity of a 1988 ditch sampling campaign and the effectiveness of subsequent stabilization. The purpose of the proposed sampling and analysis activities is to characterize soil contamination in the vicinity of a proposed road over the 216-A-29 Ditch

  20. Final report: Initial ecosystem response of salt marshes to ditch plugging and pool creation: Experiments at Rachel Carson National Wildlife Refuge (Maine)

    Science.gov (United States)

    Adamowicz, S.C.; Roman, C.T.

    2002-01-01

    This study evaluates the response of three salt marshes, associated with the Rachel Carson National Wildlife Refuge (Maine), to the practice of ditch plugging. Drainage ditches, originally dug to drain the marsh for mosquito control or to facilitate salt hay farming, are plugged with marsh peat in an effort to impound water upstream of the plug, raise water table levels in the marsh, and increase surface water habitat. At two study sites, Moody Marsh and Granite Point Road Marsh, ditch plugs were installed in spring 2000. Monitoring of hydrology, vegetation, nekton and bird utilization, and marsh development processes was conducted in 1999, before ditch plugging, and then in 2000 and 2001 (all parameters except nekton), after ditch plugging. Each study site had a control marsh that was monitored simultaneously with the plugged marsh, and thus, we employed a BACI study design (before, after, control, impact). A third site, Marshall Point Road Marsh, was plugged in 1998. Monitoring of the plugged and control sites was conducted in 1999 and 2000, with limited monitoring in 2001, thus there was no ?before? plug monitoring. With ditch plugging, water table levels increased toward the marsh surface and the areal extent of standing water increased. Responding to a wetter substrate, a vegetation change from high marsh species (e.g., Spartina patens) to those more tolerant of flooded conditions (e.g., Spartina alterniflora) was noted at two of the three ditch plugged sites. Initial response of the nekton community (fishes and decapod crustaceans) was evaluated by monitoring utilization of salt marsh pools using a 1m2 enclosure trap. In general, nekton species richness, density, and community structure remained unchanged following ditch plugging at the Moody and Granite Point sites. At Marshall Point, species richness and density (number of individuals per m2) were significantly greater in the experimental plugged marsh than the control marsh (<2% of the control marsh was

  1. Land use, land cover, and drainage on the Albemarle-Pamlico Peninsula, Eastern North Carolina, 1974

    Science.gov (United States)

    Daniel, C.C.

    1978-01-01

    A land use, land cover, and drainage map of the 2,000-square-mile Albermarle-Pamlico peninsula of eastern North Carolina has been prepared, at a scale of 1:125,000, as part of a larger study of the effects of large-scale land clearing on regional hydrology. The peninsula includes the most extensive area of wetland in North Carolina and one of the largest in the country. In recent years the pace of land clearing on the peninsula has accelerated as land is being converted from forest, swamp, and brushland to agricultural use. Conversion of swamps to intensive farming operations requires profound changes in the landscape. Vegetation is uprooted and burned and ditches and canals are dug to remove excess water. What is the impact of these changes on ground-water supplies and on the streams and surrounding coastal waters which receive the runoff This map will aid in answering these and similar questions that have arisen about the patterns of land use and the artificial drainage system that removes excess water from the land. By showing both land use and drainage, this map can be used to identify those areas where water-related problems may occur and help assess the nature and causes of these problems. The map covers the entire area east of the Suffolk Scarp, an area of about 2,000 square miles, for the year 1974 using data from 1974-76. Land use and land cover were compiled and modified from the U.S. Geological Survey 's Rocky Mount and Manteo LUDA maps. Additional information came from U.S. Geological Survey orthophotoquads, Landsat imagery, and field checking. Drainage was mapped from orthophotoquads, some field inspection, and 7-1/2 minute topographic quadrangle maps.

  2. MANUAL OF TEMPORARY EROSION CONTROL PRODUCTS FOR ROADSIDE DITCHES

    Science.gov (United States)

    2017-09-01

    Sediment continues to be the primary pollutant by volume in Ohio's streams and rivers. Unvegetated roadside ditches' side slopes and bottoms erode and contribute tons of sediment annually to local receiving streams. Pollutants attach themselves to se...

  3. Soil/sediment characterization for 216-A-29 ditch

    International Nuclear Information System (INIS)

    Mitchell, R.M.

    1997-01-01

    This document provides a detailed description of the environmental samples collected from the 216-A-29 Ditch in 1988. Tables summarizing the laboratory data for radionuclides, metals, and soil chemistry are included

  4. Soil/sediment characterization for 216-A-29 ditch

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, R.M.

    1997-03-01

    This document provides a detailed description of the environmental samples collected from the 216-A-29 Ditch in 1988. Tables summarizing the laboratory data for radionuclides, metals, and soil chemistry are included.

  5. Subsurface drainage

    CSIR Research Space (South Africa)

    Van Der

    1993-09-01

    Full Text Available and long term behavior were evaluated. Laboratory tests for geotextile selection are recommended and tentative criteria given. The use of fin drains was evaluated in the laboratory and a field study to monitor the efficacy of drainage systems was started...

  6. Detecting seasonal and cyclical trends in agricultural runoff water quality-hypothesis tests and block bootstrap power analysis.

    Science.gov (United States)

    Uddameri, Venkatesh; Singaraju, Sreeram; Hernandez, E Annette

    2018-02-21

    Seasonal and cyclic trends in nutrient concentrations at four agricultural drainage ditches were assessed using a dataset generated from a multivariate, multiscale, multiyear water quality monitoring effort in the agriculturally dominant Lower Rio Grande Valley (LRGV) River Watershed in South Texas. An innovative bootstrap sampling-based power analysis procedure was developed to evaluate the ability of Mann-Whitney and Noether tests to discern trends and to guide future monitoring efforts. The Mann-Whitney U test was able to detect significant changes between summer and winter nutrient concentrations at sites with lower depths and unimpeded flows. Pollutant dilution, non-agricultural loadings, and in-channel flow structures (weirs) masked the effects of seasonality. The detection of cyclical trends using the Noether test was highest in the presence of vegetation mainly for total phosphorus and oxidized nitrogen (nitrite + nitrate) compared to dissolved phosphorus and reduced nitrogen (total Kjeldahl nitrogen-TKN). Prospective power analysis indicated that while increased monitoring can lead to higher statistical power, the effect size (i.e., the total number of trend sequences within a time-series) had a greater influence on the Noether test. Both Mann-Whitney and Noether tests provide complementary information on seasonal and cyclic behavior of pollutant concentrations and are affected by different processes. The results from these statistical tests when evaluated in the context of flow, vegetation, and in-channel hydraulic alterations can help guide future data collection and monitoring efforts. The study highlights the need for long-term monitoring of agricultural drainage ditches to properly discern seasonal and cyclical trends.

  7. Efficient phosphorus management practices in the Everglades Agricultural Area

    Science.gov (United States)

    Bhadha, J. H.; Lang, T. A.; Daroub, S. H.; Alvarez, O.; Tootoonchi, M.; Capasso, J.

    2016-12-01

    In the 450,000 acres of the Everglades Agricultural Area (EAA) of South Florida, farming practices have long been mindful of phosphorus (P) management as it relates to sufficiency and efficiency of P utilization. Over two decades of P best management practices have resulted in 3001 metric-ton of P load reduction from the EAA to downstream ecosystems. During the summer, more than 50,000 acres of fallow sugarcane land is available for rice production. The net value of growing flooded rice in the EAA as a rotational crop with sugarcane far exceeds its monetary return. Soil conservation, improvement in tilth and P load reduction are only some of the benefits. With no P fertilizer applied, a two-year field trial on flooded rice showed improved outflow P concentrations by up to 40% as a result of particulate setting and plant P uptake. Harvested whole grain rice can effectively remove a significant amount of P from a rice field per growing season. In parts of the EAA where soils are sandy, the application of using locally derived organic amendments as potential P fertilizer has gained interest over the past few years. The use of local agricultural and urban organic residues as amendments in sandy soils of South Florida provide options to enhance soil properties and improve sugarcane yields, while reducing waste and harmful effects of agricultural production on the environment. A lysimeter study conducted to determine the effect of mill ash and three types of biochar (rice hulls, yard waste, horse bedding) on sugarcane yields, soil properties, and drainage water quality in sandy soils showed that mill ash and rice hull biochar increased soil TP, Mehlich 3-P (M3-P), and cation exchange capacity (CEC) compared to the control. TP and M3-P content remained constant after 9 months, CEC showed a significant increase over time with rich hull biochar addition. Future projects include the utilization of aquatic vegetation, such as chara and southern naiad as bio-filters in farm

  8. Conditions and mechanisms affecting simultaneous nitrification and denitrification in a Pasveer oxidation ditch

    NARCIS (Netherlands)

    Hao, X.; Doddema, H.J.; Groenestijn, J.W. van

    1997-01-01

    Simultaneous nitrification and denitrification in a Pasveer oxidation ditch was studied. The purpose was to evaluate the performances of both nitrification and dentrification in oxidation ditches, and to pursue some possible approaches to enhance nitrogen removal. Almost complete nitrification was

  9. Achieving Long-Term Protection of Water Quality of Grand Lake St. Marys Through Implementation of Conservation Practices and Control of Phosphorus Input from Agricultural Drainage

    Science.gov (United States)

    Grand Lake St. Marys (GLSM), a 13,000 acre lake in northwestern Ohio, is experiencing toxic levels of algal blooms resulting primarily from phosphorus input from agricultural runoff. The algal blooms are so severe that the Ohio Department of Natural Resources advised against any...

  10. Iowa state highway 92 over drainage ditch #25 : performance evaluation - galvanized reinforcing bars, Louisa County, Iowa.

    Science.gov (United States)

    2015-06-01

    Several strategies are available to the Iowa Department of Transportation (IaDOT) for limiting : deterioration due to chloride-induced corrosion of embedded reinforcing bars in concrete bridge decks. : While the method most commonly used throughout t...

  11. Consideration of drainage ditches and sediment rating cure on SWAT model performance

    Science.gov (United States)

    Water quality models most often require a considerable amount of data to be properly configured and in some cases this requires additional procedural steps prior to model applications. We examined two different scenarios of such input issues in a small watershed using the Soil and Water Assessment ...

  12. Urban Floods Adaptation and Sustainable Drainage Measures

    Directory of Open Access Journals (Sweden)

    Helena M. Ramos

    2017-11-01

    Full Text Available Sustainability is crucial to the urban zones, especially related to the water management, which is vulnerable to flood occurrence. This research applies the procedure contemplated by the Soil Conservation Service (SCS to determine the generated volumes when the impervious areas can exceed the drainage capacity of existing pluvial water networks. Several computational simulations were developed for the current scenario of an existing basin in Lisbon. Using CivilStorm software from Bentley Systems (Bentley EMEA, Bentley Systems International Limited, Dublin, Ireland, it enabled the evaluation of the volumes of flood peaks and the hydraulic behavior of a small hydrographic basin in the continuation of an urbanization process, considering the modification of its superficial impervious parts and the growth of the urbanized area. Several measures are suggested to solve the limited capacity of the existing drainage system. This study analyzes the efficiency of the application of constructive measures, pondering the viability of their effectiveness, individually and combined. The option that best minimizes the effects of the urbanization is the combination of different structural measures, in particular retention ponds, storage blocks, ditches and specific drainage interventions in some parts of the network.

  13. Improving low-relief coastal LiDAR DEMs with hydro-conditioning of fine-scale and artificial drainages

    Directory of Open Access Journals (Sweden)

    Thomas Richard Allen

    2015-11-01

    Full Text Available Improvements in Light Detection and Ranging (LiDAR technology and spatial analysis of high-resolution digital elevation models (DEMs have advanced the accuracy and diversity of applications for coastal hazards and natural resources management. This article presents a concise synthesis of LiDAR analysis for coastal flooding and management applications in low-relief coastal plains and a case study demonstration of a new, efficient drainage mapping algorithm. The impetus for these LiDAR applications follows historic flooding from Hurricane Floyd in 1999, after which the State of North Carolina and the Federal Emergency Management Agency undertook extensive LiDAR data acquisition and technological developments for high-resolution floodplain mapping. An efficient algorithm is outlined for hydro-conditioning bare earth LiDAR DEMs using available US Geological Survey National Hydrography Dataset canal and ditch vectors. The methodology is illustrated in Moyock, North Carolina, for refinement of hydro-conditioning by combines pre-existing bare earth DEMs with spatial analysis of LiDAR point clouds in segmented and buffered ditch and canal networks. The methodology produces improved maps of fine-scale drainage, reduced omission of areal flood inundation, and subwatershed delineations that typify heavily ditched and canalled drainage areas. These preliminary results illustrate the capability of the technique to improve the representation of ditches in DEMs as well as subsequent flow and inundation modeling that could spur further research on low-relief coastal LiDAR applications.

  14. Treatment of animal carcasses in poultry farms using sealed ditches.

    Science.gov (United States)

    Sánchez, M; González, J L; Gutiérrez, M A Díez; Guimaraes, A Correa; Gracia, L M Navas

    2008-10-01

    Several hen carcass elimination experiments were conducted by isolating corpses in a sealed ditch and adding different doses of lime. The aim was to evaluate the viability of this method as an alternative to other elimination techniques, as required in the European regulation CE 1774/2002 [Reglamento CE 1774/2002, de 3 de octubre por el que se establecen las normas sanitarias aplicables a los subproductos animales no destinados a consumo humano]. The experiments were carried out at a natural scale, in a 200m3 ditch located in a livestock enterprise, using a proportion of 200g of lime/kg of carcass. We observed a high degradation of carcasses after six months, the method being also safe from a microbiological point of view. The material extracted from the ditch had a high calcium content (330.7gkg(-1)), which makes it an ideal product for soil lacking this element, or as an acidity corrector in acid soils due to its basic (pH 8.48) nature. It also contains a significant amount of mineral nutrients (17.0gkg(-1) N, 2.4gkg(-1) P and 4.9gkg(-1) K) and organic matter (101.5gkg(-1)). We also analysed the material extracted from the ditch prior to its renovation for the experiments and followed the processes taking place in the ditch during the first six months, when lime doses of 100, 200 and 300 gkg(-1) of treated carcass were applied. Simultaneously, we carried out laboratory experiments in cylindrical 25L deposits to evaluate the gas release of the three (100, 200 and 300g of lime/kg carcass) doses of lime used. After the tenth week, we observed CO2 concentrations ranging from 5% for the lower lime doses to very low levels for the 300g lime/kg carcass dose. As regards methane, in the three series of experiments, the release was highest during the first weeks, began to decrease in the eighth week and reached its lower value during the fourteenth week. Emissions of NO2 were not observed, and the levels of NH3 and SH2 were usually so high that they exceeded the detection

  15. Seepage patterns of Diuron in a ditch bed during a sequence of flood events

    International Nuclear Information System (INIS)

    Dages, C.; Samouëlian, A.; Negro, S.; Storck, V.; Huttel, O.; Voltz, M.

    2015-01-01

    Although ditches limit surface water contamination, groundwater recharge through ditches in Mediterranean catchments may result in groundwater contamination. We analysed the dynamics of pesticide percolation in ditches by conducting an original lab experiment that mimicked the successive percolation processes that occur during a flood season. Nine successive percolation events were operated on an undisturbed soil column collected from a ditch bed. The infiltrating water was doped with 14 C-Diuron at concentrations that were chosen to decrease between the events so as to correspond to values observed during actual flood events. The water and solute fluxes were monitored during each event, and the final extractable and non-extractable Diuron residues in the column were determined. Two main observations were made. First, a high leaching potential was observed through the ditch bed over a succession of infiltrating flood events, with 58.9% of the infiltrated Diuron and its metabolites leaching. Second, compared with the contamination of surface water circulating in the ditches, the contamination of seepage water exhibited smaller peak values and persisted much longer because of the desorption of Diuron residues stored in the ditch bed. Thus, ditches serve as buffering zones between surface and groundwater. However, compared with field plots, ditches appear to be a preferential location for the percolation of pesticides into groundwater at the catchment scale. - Highlights: • Diuron percolation in a ditch bed during flood events was mimicked in a column setup. • Diuron percolation can represent up to 50% of the infiltrated Diuron. • The ditch bed exhibits a high buffering capacity due to its high sorption properties. • Contamination period of percolation water lasts longer than that of infiltrating water. • Diuron residues stored in ditch bed move deeper than in field topsoils.

  16. Seepage patterns of Diuron in a ditch bed during a sequence of flood events

    Energy Technology Data Exchange (ETDEWEB)

    Dages, C., E-mail: cecile.dages@supagro.inra.fr; Samouëlian, A.; Negro, S.; Storck, V.; Huttel, O.; Voltz, M.

    2015-12-15

    Although ditches limit surface water contamination, groundwater recharge through ditches in Mediterranean catchments may result in groundwater contamination. We analysed the dynamics of pesticide percolation in ditches by conducting an original lab experiment that mimicked the successive percolation processes that occur during a flood season. Nine successive percolation events were operated on an undisturbed soil column collected from a ditch bed. The infiltrating water was doped with {sup 14}C-Diuron at concentrations that were chosen to decrease between the events so as to correspond to values observed during actual flood events. The water and solute fluxes were monitored during each event, and the final extractable and non-extractable Diuron residues in the column were determined. Two main observations were made. First, a high leaching potential was observed through the ditch bed over a succession of infiltrating flood events, with 58.9% of the infiltrated Diuron and its metabolites leaching. Second, compared with the contamination of surface water circulating in the ditches, the contamination of seepage water exhibited smaller peak values and persisted much longer because of the desorption of Diuron residues stored in the ditch bed. Thus, ditches serve as buffering zones between surface and groundwater. However, compared with field plots, ditches appear to be a preferential location for the percolation of pesticides into groundwater at the catchment scale. - Highlights: • Diuron percolation in a ditch bed during flood events was mimicked in a column setup. • Diuron percolation can represent up to 50% of the infiltrated Diuron. • The ditch bed exhibits a high buffering capacity due to its high sorption properties. • Contamination period of percolation water lasts longer than that of infiltrating water. • Diuron residues stored in ditch bed move deeper than in field topsoils.

  17. Fate of the insecticide lambda-cyhalothrin in ditch enclosures differing in vegetation density.

    Science.gov (United States)

    Leistra, Minze; Zweers, Anton J; Warinton, Jacqui S; Crum, Steven J H; Hand, Laurence H; Beltman, Wim H J; Maund, Stephen J

    2004-01-01

    Use of the insecticide lambda-cyhalothrin in agriculture may result in the contamination of water bodies, for example by spray drift. Therefore, the possible exposure of aquatic organisms to this insecticide needs to be evaluated. The exposure of the organisms may be reduced by the strong sorption of the insecticide to organic materials and its susceptibility to hydrolysis at the high pH values in the natural range. In experiments done in May and August, formulated lambda-cyhalothrin was mixed with the water body of enclosures in experimental ditches containing a bottom layer and macrophytes (at different densities) or phytoplankton. Concentrations of lambda-cyhalothrin in the water body and in the sediment layer, and contents in the plant compartment, were measured by gas-liquid chromatography at various times up to 1 week after application. Various water quality parameters were also measured. Concentrations of lambda-cyhalothrin decreased rapidly in the water column: 1 day after application, 24-40% of the dose remained in the water, and by 3 days it had declined to 1.8-6.5%. At the highest plant density, lambda-cyhalothrin residue in the plant compartment reached a maximum of 50% of the dose after 1 day; at intermediate and low plant densities, this maximum was only 3-11% of the dose (after 1-2 days). The percentage of the insecticide in the ditch sediment was 12% or less of the dose and tended to be lower at higher plant densities. Alkaline hydrolysis in the water near the surface of macrophytes and phytoplankton is considered to be the main dissipation process for lambda-cyhalothrin.

  18. Results of the groundwater quality assessment program at the 216-A-29 ditch RCRA facility

    International Nuclear Information System (INIS)

    Votava, J.M.

    1995-01-01

    This report presents the findings of the groundwater quality assessment program for the 216-A-29 Ditch. The information presented in this report Ditch have affected the quality of the groundwater in the unconfined aquifer beneath the facility. The results indicate that the 216-A-29 Ditch is the source of elevated specific conductance in well 299-E25-35 and that the source is nonhazardous. This report describes the current monitoring status of the 216-A-29 Ditch, groundwater chemical data interpretation, and recommends the reinstatement of an indicator-evaluation monitoring program in accordance with 40 CFR 265.93(d)(6)

  19. Prairie Pothole Region wetlands and subsurface drainage systems: Key factors for determining drainage setback distances

    Science.gov (United States)

    Tangen, Brian; Wiltermuth, Mark T.

    2018-01-01

    Use of agricultural subsurface drainage systems in the Prairie Pothole Region of North America continues to increase, prompting concerns over potential negative effects to the Region's vital wetlands. The U.S. Fish and Wildlife Service protects a large number of wetlands through conservation easements that often utilize standard lateral setback distances to provide buffers between wetlands and drainage systems. Because of a lack of information pertaining to the efficacy of these setback distances for protecting wetlands, information is required to support the decision making for placement of subsurface drainage systems adjacent to wetlands. We used qualitative graphical analyses and data comparisons to identify characteristics of subsurface drainage systems and wetland catchments that could be considered when assessing setback distances. We also compared setback distances with catchment slope lengths to determine if they typically exclude drainage systems from the catchment. We demonstrated that depth of a subsurface drainage system is a key factor for determining drainage setback distances. Drainage systems located closer to the surface (shallow) typically could be associated with shorter lateral setback distances compared with deeper systems. Subsurface drainage systems would be allowed within a wetland's catchment for 44–59% of catchments associated with wetland conservation easements in North Dakota. More specifically, results suggest that drainage setback distances generally would exclude drainage systems from catchments of the smaller wetlands that typically have shorter slopes in the adjacent upland contributing area. For larger wetlands, however, considerable areas of the catchment would be vulnerable to drainage that may affect wetland hydrology. U.S. Fish and Wildlife Service easements are associated with > 2,000 km2 of wetlands in North Dakota, demonstrating great potential to protect these systems from drainage depending on policies for installing

  20. Attributes for NHDPlus Catchments (Version 1.1) in the Conterminous United States: Artificial Drainage (1992) and Irrigation Types (1997)

    Science.gov (United States)

    Wieczorek, Michael; LaMotte, Andrew E.

    2010-01-01

    This tabular dataset represents the estimated area of artificial drainage for the year 1992 and irrigation types for the year 1997 compiled for every catchment of NHDPlus for the conterminous United States. The source datasets were derived from tabular National Resource Inventory (NRI) datasets created by the National Resources Conservation Service (NRCS, U.S. Department of Agriculture, 1995, 1997). Artificial drainage is defined as subsurface drains and ditches. Irrigation types are defined as gravity and pressure. Subsurface drains are described as conduits, such as corrugated plastic tubing, tile, or pipe, installed beneath the ground surface to collect and/or convey drainage. Surface drainage field ditches are described as graded ditches for collecting excess water. Gravity irrigation source is described as irrigation delivered to the farm and/or field by canals or pipelines open to the atmosphere; and water is distributed by the force of gravity down the field by: (1) A surface irrigation system (border, basin, furrow, corrugation, wild flooding, etc.) or (2) Sub-surface irrigation pipelines or ditches. Pressure irrigation source is described as irrigation delivered to the farm and/or field in pump or elevation-induced pressure pipelines, and water is distributed across the field by: (1) Sprinkle irrigation (center pivot, linear move, traveling gun, side roll, hand move, big gun, or fixed set sprinklers), or (2) Micro irrigation (drip emitters, continuous tube bubblers, micro spray or micro sprinklers). NRI data do not include Federal lands and are thus excluded from this dataset. The tabular data for drainage were spatially apportioned to the National Land Cover Dataset (NLCD, Kerie Hitt, written commun., 2005) and the tabular data for irrigation were spatially apportioned to an enhanced version of the National Land Cover Dataset (NLCDe, Nakagaki and others 2007) The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that

  1. Peat drainage conditions assessment in Scotland

    Science.gov (United States)

    Poggio, Laura; Artz, Rebekka; Donaldson-Selby, Gillian; Aitkenhead, Matt; Donnelly, David; Gimona, Alessandro

    2017-04-01

    Large areas of Scotland are covered in peat, providing an important sink of carbon but also a notable source of emission where peatlands are not in good condition. However, despite data from designated sites that peat degradation is common, a detailed spatial assessment of the condition of most peatlands across the whole of Scotland is missing. An assessment of peatland drainage was carried out at >600 random sampling locations with an expert-based estimation of presence or absence of drainage ditches within a 500 metre block using 25 cm resolution aerial imagery. The resulting dataset was modelled using a scorpan-kriging approach, in particular using Generalised Additive Models for the description of the trend. Remote sensing images from different sensors (i.e. MODIS, Landsat and Sentinel 1 and 2) were used. In particular we used indices describing vegetation greenness (Enhanced Vegetation Index), water availability (Normalised Water Difference index), Land Surface Temperature and vegetation productivity. When considering MODIS indices we used time series and phenological summaries. The model provides also uncertainty of the estimations. The derived dataset can then be used in the decision making process for the selection of sites for restoration, emissions estimation and accounting.

  2. Drainage of radioactive areas

    International Nuclear Information System (INIS)

    1981-04-01

    This Code of Practice covers all the drainage systems which may occur in the radioactive classified area of an establishment, namely surface water, foul, process and radioactive drainage. It also deals with final discharge lines. The Code of Practice concentrates on those aspects of drainage which require particular attention because the systems are in or from radioactive areas and typical illustrations are given in appendices. The Code makes references to sources of information on conventional aspects of drainage design. (author)

  3. Transient drainage summary report

    International Nuclear Information System (INIS)

    1996-09-01

    This report summarizes the history of transient drainage issues on the Uranium Mill Tailings Remedial Action (UMTRA) Project. It defines and describes the UMTRA Project disposal cell transient drainage process and chronicles UMTRA Project treatment of the transient drainage phenomenon. Section 4.0 includes a conceptual cross section of each UMTRA Project disposal site and summarizes design and construction information, the ground water protection strategy, and the potential for transient drainage

  4. Mine drainage treatment

    OpenAIRE

    Golomeova, Mirjana; Zendelska, Afrodita; Krstev, Boris; Golomeov, Blagoj; Krstev, Aleksandar

    2012-01-01

    Water flowing from underground and surface mines and contains high concentrations of dissolved metals is called mine drainage. Mine drainage can be categorized into several basic types by their alkalinity or acidity. Sulfide rich and carbonate poor materials are expected to produce acidic drainage, and alkaline rich materials, even with significant sulfide concentrations, often produce net alkaline water. Mine drainages are dangerous because pollutants may decompose in the environment. In...

  5. Reducing nitrogen export from the corn belt to the Gulf of Mexico: agricultural strategies for remediating hypoxia

    Science.gov (United States)

    McLellan, Eileen; Robertson, Dale M.; Schilling, Keith; Tomer, Mark; Kostel, Jill; Smith, Douglas G.; King, Kevin

    2015-01-01

    SPAtially Referenced Regression on Watershed models developed for the Upper Midwest were used to help evaluate the nitrogen-load reductions likely to be achieved by a variety of agricultural conservation practices in the Upper Mississippi-Ohio River Basin (UMORB) and to compare these reductions to the 45% nitrogen-load reduction proposed to remediate hypoxia in the Gulf of Mexico (GoM). Our results indicate that nitrogen-management practices (improved fertilizer management and cover crops) fall short of achieving this goal, even if adopted on all cropland in the region. The goal of a 45% decrease in loads to the GoM can only be achieved through the coupling of nitrogen-management practices with innovative nitrogen-removal practices such as tile-drainage treatment wetlands, drainage–ditch enhancements, stream-channel restoration, and floodplain reconnection. Combining nitrogen-management practices with nitrogen-removal practices can dramatically reduce nutrient export from agricultural landscapes while minimizing impacts to agricultural production. With this approach, it may be possible to meet the 45% nutrient reduction goal while converting less than 1% of cropland in the UMORB to nitrogen-removal practices. Conservationists, policy makers, and agricultural producers seeking a workable strategy to reduce nitrogen export from the Corn Belt will need to consider a combination of nitrogen-management practices at the field scale and diverse nitrogen-removal practices at the landscape scale.

  6. Groundwater Monitoring Plan for the 216-S-10 Pond and Ditch, Interim Change Notice 1

    International Nuclear Information System (INIS)

    Williams, Bruce A.

    2003-01-01

    During 2003, the upgradient well 299-W26-7 went dry and one new groundwater monitoring well was installed downgradient (well 299-W26-14) of the 216-S-10 pond and ditch. This ICN updates the groundwater monitoring wells for the 216-S-10 pond and ditch and adds a revised well location map to the plan

  7. Effects of traffic and ditch maintenance on forest road sediment production

    Science.gov (United States)

    Charles H. Luce; Thomas A. Black

    2001-01-01

    Observations of sediment yield from road segments in the Oregon Coast Range show that either heavy traffic during rainfall or blading the road ditch will increase erosion from forest roads. For the fine soils and high quality aggregate surfacing on the study plots, ditch blading increased sediment yield more than traffic equivalent to 12 log trucks per day. The...

  8. The dynamics of dissolved oxygen concentration for water quality monitoring and assessment in polder ditches

    NARCIS (Netherlands)

    Veeningen, R.

    1983-01-01

    This study deals with the use of the dynamics of dissolved oxygen concentration for water quality assessment in polder ditches. The dynamics of the dissolved oxygen concentration, i.e. the temporal and spatial variations in a few polder ditches under a range of natural, pollution and management

  9. Using bamboo (Bambusa vulgaris) as a field drainage material in ...

    African Journals Online (AJOL)

    Bamboo (Bambusa vulgaris), one of the most widespread member of its genus, was used as field drainage material in Akure, Nigeria. Pre-determined sizes of bamboo with uniform lengths and diameters were installed as sub-drains in agricultural field for drainage purposes, especially in developing countries like Nigeria.

  10. Conservation value of post-mining headwaters: drainage channels at a lignite spoil heap harbour threatened stream fragonflies

    Czech Academy of Sciences Publication Activity Database

    Tichánek, Filip; Tropek, Robert

    2015-01-01

    Roč. 19, č. 5 (2015), s. 975-985 ISSN 1366-638X R&D Projects: GA ČR GAP504/12/2525 Grant - others:GA JU(CZ) 168/2013/P Institutional support: RVO:60077344 Keywords : biodiversity conservation * drainage ditches * freshwater habitats Subject RIV: EH - Ecology, Behaviour Impact factor: 1.431, year: 2015 http://link.springer.com/article/10.1007%2Fs10841-015-9814-1

  11. Effects of peatland drainage management on peak flows

    Directory of Open Access Journals (Sweden)

    C. E. Ballard

    2012-07-01

    Full Text Available Open ditch drainage has historically been a common land management practice in upland blanket peats, particularly in the UK. However, peatland drainage is now generally considered to have adverse effects on the upland environment, including increased peak flows. As a result, drain blocking has become a common management strategy in the UK over recent years, although there is only anecdotal evidence to suggest that this might decrease peak flows. The change in the hydrological regime associated with the drainage of blanket peat and the subsequent blocking of drains is poorly understood, therefore a new physics-based model has been developed that allows the exploration of the associated hydrological processes. A series of simulations is used to explore the response of intact, drained and blocked drain sites at field scales. While drainage is generally found to increase peak flows, the effect of drain blocking appears to be dependent on local conditions, sometimes decreasing and sometimes increasing peak flows. Based on insights from these simulations we identify steep smooth drains as those that would experience the greatest reduction in field-scale peak flows if blocked and recommend that future targeted field studies should be focused on examining surface runoff characteristics.

  12. WATER DRAINAGE MODEL

    International Nuclear Information System (INIS)

    Case, J.B.

    2000-01-01

    The drainage of water from the emplacement drift is essential for the performance of the EBS. The unsaturated flow properties of the surrounding rock matrix and fractures determine how well the water will be naturally drained. To enhance natural drainage, it may be necessary to introduce engineered drainage features (e.g. drilled holes in the drifts), that will ensure communication of the flow into the fracture system. The purpose of the Water Drainage Model is to quantify and evaluate the capability of the drift to remove water naturally, using the selected conceptual repository design as a basis (CRWMS M andO, 1999d). The analysis will provide input to the Water Distribution and Removal Model of the EBS. The model is intended to be used to provide postclosure analysis of temperatures and drainage from the EBS. It has been determined that drainage from the EBS is a factor important to the postclosure safety case

  13. Social impact assessment of subsurface drainage

    International Nuclear Information System (INIS)

    Azhar, A.H.; Rafiq, M.; Alam, M.M.

    2005-01-01

    Social impact assessment of four drainage projects namely; Mardan SCARP Project (MSP), Fourth Drainage Project, Faisalabad (FDP), Chashma Command Area Development Project (CCADP) and Mirpurkhas Tile Drainage Project (MKOP) has been done. For this purpose, a socio-technical survey was carried out in which randomly selected farmers were interviewed. The investigations revealed that although significant population (-77%) at four study sites was educated, yet, the farmers were not satisfactorily educated to understand the operation and maintenance of drainage systems. The perusal of data revealed that 14%, 17% and 25% respondents from MSP, FOP and MKDP respectively had to migrate from their villages mainly due to pre-project water logging problem. However, installation of drainage systems in those areas improved the situation resulting in the increase of farm income, which was an attraction for them to return to their villages. The analysis of farm mechanization revealed that at MSP, FDP, CCADP and MKOP sites 71%, 42%, 40% and 75% respondents respectively were tractor owners and owners of some kind of other farm implements, whereas, remaining respondents were performing their farm operations on hire basis. Although, hire operation basis is much better than traditional ways, however, improving the farm mechanization could further enhance the benefits of drainage systems. The investigations revealed that a significant majority of respondents at four project sites had never met the Agricultural Extension Officer. The farmers' access to financing institutions such as ZTB was also negligible. There was lack of coordination among various departments such as WAPDA, Agriculture Extension and Irrigation and Power Department at four study sites. Nevertheless, the overall social impact investigations did reveal that the objectives of drainage systems installation have been achieved in terms of uplifting the socio-economic conditions of drainage areas. To make the efficient use of

  14. Solar system for soil drainage

    International Nuclear Information System (INIS)

    Kocic, Z.R.; Stojanovic, J.B.; Antic, M.A.; Pavlovic, T.M.

    1999-01-01

    The paper reviews solar system for drainage of the cultivable agricultural surfaces which can be situated near the rivers in plains. These are usually very fertile surfaces which cannot be cultivated die to constant presence of the water. Using such solar systems should increase the percentage of cultivable surfaces. These systems can also be installed on the cultivable agricultural surfaces, where the water surfaces or so called still waters appear, which make impossible the application of agritechnical measures on these surfaces, significantly decreasing crops and creating conditions for the growth of pond plants and animals. Increasing the percentage of cultivable agricultural surfaces would increase national agricultural income. At the same time, increasing the percentage of cultivable agricultural surfaces decreases the surfaces of unhealthy bog, swamp and marshland soils, where many insect breed. They are the cause for soil spraying from the air, which causes the pollution of environment. Solar systems do not pollute the environment because they use solar energy as the purest source of energy. Their usage has special significance in the places where there is no electricity distribution network

  15. Drainage filters and constructed wetlands to mitigate sitespecific nutrient losses

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Canga, Eriona; Heckrath, Goswin Johann

    2012-01-01

    Research Council, aims at providing the scientific basis for developing cost-effective filter technologies targeting P-retention and N-removal in agricultural subsurface drainage. The project studies different approaches of implementing the filter technologies including drainage well filters as well...... typically applied to point sources. This calls for a shift of paradigm towards the development of new, cost-efficient technologies to mitigate site-specific nutrient losses in drainage. A newly launched Danish research project “SUPREME-TECH” (2010-2015) (www.supreme-tech.dk) funded by the Danish Strategic...... in drainage water to below environmental threshold values (

  16. Laboratory and field experience with rim ditch dewatering of MFT

    Energy Technology Data Exchange (ETDEWEB)

    Demoz, A.; Mikula, R. [Natural Resources Canada, Devon, AB (Canada). CANMET Western Research Centre; Lahaie, R. [Syncrude Canada Ltd., Edmonton, AB (Canada)

    2010-07-01

    This PowerPoint presentation described a rim ditch method of dewatering mature fine tailings (MFT). Polymer additions were used to strengthen the MFT and to decrease the capillary suction time (CST). Laboratory and field-scale studies were conducted to demonstrate the dewatering method. The flocculants were added in a Komax inline mixer. Polymers were then injected into the tailings. The mixing processes were optimized in a series of laboratory studies and then demonstrated in the field tests. The tests showed that CST and high dewatering rates were consistently maintained using the method. MFT feeds were also consistent. Release water quality was improved using the method. The large-scale test site is now being monitored for compliance with Directive 74. tabs., figs.

  17. Groundwater impact assessment report for the 216-U-14 Ditch

    Energy Technology Data Exchange (ETDEWEB)

    Singleton, K.M.; Lindsey, K.A.

    1994-01-01

    Groundwater impact assessments are conducted at liquid effluent receiving sites on the Hanford Site to determine hydrologic and contaminant impacts caused by discharging wastewater to the soil column. The assessments conducted are pursuant to the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Milestone M-17-00A and M-17-00B, as agreed by the US Department of Energy (DOE), Washington State Department of Ecology (Ecology), and the US Environmental Protection Agency (EPA) (Ecology et al. 1992). This report assesses impacts on the groundwater and vadose zone from wastewater discharged to the 216-U-14 Ditch. Contemporary effluent waste streams of interest are 242-S Evaporator Steam Condensate and UO{sub 3}/U Plant wastewater.

  18. Hypnobirth within the NHS: time to ditch the parent craft?

    Science.gov (United States)

    Gavin-Jones, Teri

    2016-05-01

    Antenatal education within the National Health Service (NHS) is a service in decline within some hospital trusts. Classes on offer are being moved into online formats or discontinued completely. Whilst research into antenatal education remains limited, what is known is that good birth preparation is of value. "Participative preparation for childbirth can enhance women's overall satisfaction with the childbirth experience" (Schrader McMillan et al 2009: 49). There are pockets of excellent antenatal education within the NHS, but no system for regulating the quality and content. Traditional 'parent craft' classes can be oversubscribed, turning what should be a participative group into an audience. Offering good quality antenatal education has the potential to increase normality, improve the birth outcome and the experience of both woman and her birth partner. Is it time to ditch the parent craft and implement dynamic woman-focused education?

  19. Pleural fluid drainage: Percutaneous catheter drainage versus surgical chest tube drainage

    International Nuclear Information System (INIS)

    Illescas, F.F.; Reinhold, C.; Atri, M.; Bret, P.M.

    1987-01-01

    Over the past 4 years, 55 cases (one transudate, 28 exudates, and 26 empymas) were drained. Surgical chest tubes alone were used in 35 drainages, percutaneous catheters alone in five drainages, and both types in 15 drainages. Percutaneous catheter drainage was successful in 12 of 20 drainages (60%). Surgical tube drainage was successful in 18 of 50 drainages (36%). The success rate for the nonempyema group was 45% with both types of drainage. For the empyema group, the success rate for percutaneous catheter drainage was 66% vs 23% for surgical tube drainage. Seven major complications occurred with surgical tube drainage, but only one major complication occurred with percutaneous catheter drainage. Radiologically guided percutaneous catheter drainage should be the procedure of choice for pleural fluid drainage. It has a higher success rate for empyemas and is associated with less complications

  20. Processes Affecting Agricultural Drainwater Quality and Organic Carbon Loads in California's Sacramento–San Joaquin Delta

    Directory of Open Access Journals (Sweden)

    Steven J. Deverel

    2007-05-01

    Full Text Available From 2000 to 2003 we quantified drain flow, drain-and ground-water chemistry and hydrogeologic conditions on Twitchell Island in the Sacramento-San Joaquin Delta. The primary objective was to quantify processes affecting organic carbon concentrations and loads in agricultural drainage water. We collected physical and chemical data in southern and northern areas: TN and TS, respectively. Corn grew in both areas during the spring and summer. The peat soils in the TN area are more decomposed than those in the TS area. Results elucidate processes affecting drain flow and concentrations under varying hydrologic conditions. During May through November, groundwater flows from the permanently saturated zone to drainage ditches, and the resulting average drainage-water quality and dissolved organic carbon (DOC concentration was similar to the groundwater; the median DOC loads in the TN and TS study areas ranged from 9 to 27 g C/ha-day. The major ion chemistry and stable isotope data confirmed that groundwater was the primary source of drainflow. In contrast, during December through April the drainwater is supplied from the shallow, variably saturated soil-zone. The DOC concentrations, major-ion chemistry, and stable isotope data indicate that the shallow-zone water is partially evaporated and oxidized. Higher flows and DOC concentrations during these months result in higher median DOC loads, which ranged from 84 to 280 g C/ha-day. During December through April, increasing groundwater levels in the shallow peat layers and mobilization of organic carbon result in high drain flow and increased trihalomethane precursor concentrations and loads. On a per mass DOC basis, drain water collected during high flow periods is less likely to form THMs than during low flow periods. However, the high flows and subsequent high concentrations contribute to substantially higher trihalomethane precursor and DOC loads.

  1. [Ascites drainage at home

    NARCIS (Netherlands)

    Lutjeboer, J.; Erkel, A.R. van; Hoeven, J.J.M. van der; Meer, R.W. van der

    2015-01-01

    Ascites can lead to many symptoms, and often occurs in patients with an end-stage malignancy such as ovarian, pancreatic, colonic, or gastric cancer. Intermittent ascites drainage is applied in these patients as a palliative measure. As frequent drainage is necessary, a subcutaneously tunnelled

  2. Development of a benchmarking methodology for evaluating oxidation ditch control strategies

    NARCIS (Netherlands)

    Abusam, A.A.A.

    2001-01-01

    Keywords: wastewater, oxidation ditch, carrousel, modeling, activated sludge, ASM No. 1, oxygen transfer rate, aeration, parameter estimation, calibration, sensitivity analysis, uncertainty analysis, sensors, horizontal

  3. Advances in drainage: Selected works from the Tenth International Drainage Symposium

    Science.gov (United States)

    Strock, Jeffrey S.; Hay, Christopher; Helmers, Matthew; Nelson, Kelly A.; Sands, Gary R.; Skaggs, R. Wayne; Douglas-Mankin, Kyle R.

    2018-01-01

    This article introduces a special collection of fourteen articles accepted from among the 140 technical presentations, posters, and meeting papers presented at the 10th International ASABE Drainage Symposium. The symposium continued in the tradition of previous symposia that began in 1965 as a forum for presenting and assessing the progress of drainage research and implementation throughout the world. The articles in this collection address a wide range of topics grouped into five broad categories: (1) crop response, (2) design and management, (3) hydrology and scale, (4) modeling, and (5) water quality. The collection provides valuable information for scientists, engineers, planners, and others working on crop production, water quality, and water quantity issues affected by agricultural drainage. The collection also provides perspectives on the challenges of increasing agricultural production in a changing climate, with ever-greater attention to water quality and quantity concerns that will require integrated technical, economic, and social solutions.

  4. Percutaneous transhepatic biliary drainage

    International Nuclear Information System (INIS)

    Park, Jae Hyung; Hong, Seong Mo; Han, Man Chung

    1982-01-01

    Percutaneous transhepatic biliary drainage was successfully made 20 times on 17 patients of obstructive jaundice for recent 1 year since June 1981 at Department of Radiology in Seoul National University Hospital. The causes of obstructive jaundice was CBD Ca in 13 cases, metastasis in 2 cases, pancreatic cancer in 1 case and CBD stone in 1 case. Percutaneous transhepatic biliary drainage is a relatively ease, safe and effective method which can be done after PTC by radiologist. It is expected that percutaneous transhepatic biliary drainage should be done as an essential procedure for transient permanent palliation of obstructive jaundice

  5. Acid Mine Drainage Treatment

    National Research Council Canada - National Science Library

    Fripp, Jon

    2000-01-01

    .... Acid mine drainage (AMD) can have severe impacts to aquatic resources, can stunt terrestrial plant growth and harm wetlands, contaminate groundwater, raise water treatment costs, and damage concrete and metal structures...

  6. Surface Water & Surface Drainage

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This data set contains boundaries for all surface water and surface drainage for the state of New Mexico. It is in a vector digital data structure digitized from a...

  7. 216-S-10 Pond and Ditch supplemental information to the Hanford Facility Contingency Plan (DOE/RL-93-75)

    International Nuclear Information System (INIS)

    Ingle, S.J.

    1996-05-01

    The 216-S-10 Pond and Ditch were used as disposal sites for the Chemical Engineering Laboratory between 1980 and 1983. The 216-S-10 Ditch last received a discharge October 1991. Both the pond and the ditch have been physically isolated, and the pond has been backfilled and decommissioned; both will be closed under final facility standards. Waste management activities are no longer required at the unit. The unit does not present and significant hazard to adjacent units, personnel, or the environment. It is unlikely that any incidents presenting hazards to public health or the environment would occur at the 215-S-10 Pond and Ditch

  8. Comparison of performance of tile drainage routines in SWAT 2009 and 2012 in an extensively tile-drained watershed in Midwest

    Science.gov (United States)

    Subsurface tile drainage systems are widely used in agricultural watersheds in the Midwestern U.S. Tile drainage systems enable the Midwest area to become highly productive agricultural lands, but can also create environmental problems, for example nitrate-N contamination associated with drainage w...

  9. Spatio-temporal relation between landslide occurrence and abandoned or not maintained agricultural terraces in the Moldavian Plateau, NE Romania

    Science.gov (United States)

    Ciprian Margarint, Mihai; Santangelo, Michele; Niculita, Mihai; Bucci, Francesco

    2016-04-01

    Terraced landscapes are one of the most obvious human-shaped landscapes, mainly used to reduce the negative impact of soil erosion due to uncontrolled runoff and shallow landslides occurrence. Nevertheless, as the recent literature emphasizes, these old best practices can transform into a potential hazard for soil degradation, if not appropriately maintained. In Moldavian Plateau (NE Romania), agricultural terraces were built after the 1960s for landslide, soil erosion and runoff control, mainly in connection with construction of reservoirs, for increasing their operation time. Usually, the slope reduction was obtained by construction of cut-off ditches, hillside ditches, intermittent terraces, bench terraces, broad-based terraces, vineyardand orchard terraces. Due to the dry climatic setting, to the lack of hard rocks for construction, and to the generally light earth moving machinery available for construction, terraces are generally characterized by a small escarpment (0.5m to 1m), and a relatively short lateral extension (5 to 40 m). When the terraces were maintained, the backslope was typically covered with grass. When, after the 1990s, the lands were returned to the initial owners, the vegetation cover of the terraces was no more maintained, and the terraces themselves were progressively abandoned, due to lack of funds. Accurate landslide mapping on high resolution LiDAR DEM derived images, allowed to produce geomorphological inventories in 5 test cases, representative of the whole study area. In each inventory, landslides were classified based on type and relative age based on published classification schemes. We investigate the spatial and temporal relation between landslides occurrence and terraces, based on the spatial interactions of landslides of different ages and terraces. Results reveal that terraces were built, both on landslide-free and landslide-bearing slopes, and that frequently landslides and gullies develop on terraced slopes. Reactivations of

  10. [Ascites drainage at home].

    Science.gov (United States)

    Lutjeboer, Jacob; van Erkel, Arian R; van der Hoeven, J J M Koos; van der Meer, Rutger W

    2015-01-01

    Ascites can lead to many symptoms, and often occurs in patients with an end-stage malignancy such as ovarian, pancreatic, colonic, or gastric cancer. Intermittent ascites drainage is applied in these patients as a palliative measure. As frequent drainage is necessary, a subcutaneously tunnelled permanent ascites catheter is a good alternative for intermittent drainage. The patient can open - and then re-close - the catheter when abdominal pressure increases. We inserted 35 subcutaneously permanent ascites catheters in the course of the past 3.5 years in the Leiden University Medical Centre. The success rate was 100% and the complication risk was 2.9%. A subcutaneously tunnelled ascites catheter is an effective and safe palliative treatment for patients with end-stage malignant disease and suffering from ascites.

  11. Van de wal in de sloot : een typologisch onderzoek aan makrofaunaprocessen

    NARCIS (Netherlands)

    Beltman, G.H.J.

    1983-01-01

    Ditches are an important structural feature of the landscape in the holocene part of the Netherlands. Ditches and other water-courses have been dug to improve drainage and make the land suitable for agriculture.
    Since ditches are two to six metres wide and are generally less than a metre deep

  12. Oxygen transfer rate estimation in oxidation ditches from clean water measurements.

    Science.gov (United States)

    Abusam, A; Keesman, K J; Meinema, K; Van Straten, G

    2001-06-01

    Standard methods for the determination of oxygen transfer rate are based on assumptions that are not valid for oxidation ditches. This paper presents a realistic and simple new method to be used in the estimation of oxygen transfer rate in oxidation ditches from clean water measurements. The new method uses a loop-of-CSTRs model, which can be easily incorporated within control algorithms, for modelling oxidation ditches. Further, this method assumes zero oxygen transfer rates (KLa) in the unaerated CSTRs. Application of a formal estimation procedure to real data revealed that the aeration constant (k = KLaVA, where VA is the volume of the aerated CSTR) can be determined significantly more accurately than KLa and VA. Therefore, the new method estimates k instead of KLa. From application to real data, this method proved to be more accurate than the commonly used Dutch standard method (STORA, 1980).

  13. Responses of zooplankton in lufenuron-stressed experimental ditches in the presence or absence of uncontaminated refuges

    NARCIS (Netherlands)

    López-Mancisidor, P.; Brink, van den P.J.; Crum, S.J.H.; Maund, S.J.; Carbonell, G.; Brock, T.C.M.

    2008-01-01

    Outdoor experimental ditches were used to evaluate the influence of untreated refuges on the recovery of zooplankton communities following treatment with the fast-dissipating insecticide lufenuron. Each experimental ditch was divided into three sections of the same surface area. The treatments

  14. Quarterly sampling of the wetlands along the old F-Area effluent ditch, Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, K.L.; cummins, C.L.

    1994-05-01

    In May 1994, well point water and bucket samples were collected for tritium and volatile organic compounds in the wetlands along the old F-Area effluent ditch south of 643-E (old burial ground). The well point samples were collected from seven locations and the bucket samples from four locations. Results support that T and VOCs originating from 643-E are outcropping in the wetlands near this ditch. Based on differences in tritium contents at each location, it was determined that the sampling devices intercepted different groundwater flow paths; however, when VOCs were normalized, based on differences in T, resulting well point and bucket VOCs were comparable in most cases.

  15. Drainage Water Filtration

    Science.gov (United States)

    Tile drainage discharge from managed turf is known to carry elevated concentrations of agronomic fertilizers and chemicals. One approach being considered to reduce the transport is end-of-tile-filters. Laboratory and field studies have been initiated to address the efficacy of this approach. Result...

  16. Wound Drainage Culture (For Parents)

    Science.gov (United States)

    ... Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Wound Drainage Culture KidsHealth / For Parents / Wound Drainage Culture What's in ...

  17. Ecological impact in ditch mesocosms of simulated spray drift from a crop protection program for potatoes

    NARCIS (Netherlands)

    Arts, G.H.P.; Buijse-Bogdan, L.L.; Belgers, J.D.M.; Rhenen-Kersten, van C.H.; Wijngaarden, van R.P.A.; Roessink, I.; Maund, S.J.; Brink, van den P.J.; Brock, T.C.M.

    2006-01-01

    Outdoor aquatic ditch mesocosms were treated with a range of pesticides to simulate various spray drift rates resulting from a typical crop protection program used in the cultivation of potatoes in The Netherlands. The main experimental aims of the present study were to provide information on the

  18. 216-U-10 Pond and 216-Z-19 Ditch characterization studies

    Energy Technology Data Exchange (ETDEWEB)

    Last, G.V.; Duncan, D.W.; Graham, M.J.; Hall, M.D.; Hall, V.W.; Landeen, D.S.; Leitz, J.G.; Mitchell, R.M.

    1994-02-01

    The chemical, reprocessing of spent nuclear fuels at the US Department of Energy`s Hanford Site has generated large volumes of radioactive liquid effluents. The majority of these effluents have been used strictly for cooling or other supportive functions and have been discharged to ditches and ponds. The 216-U-10 Pond and 216-Z-19 Ditch are two such disposal facilities. These facilities are components of an integrated system of ditches, ponds, and overflow facilities collectively referred to as the U-Pond disposal system. The U-Pond system has been used since 1943 and has received a large variety of radioisotopes from several sources. This study covered tho major aspects of the environment, including wind resuspension, biological uptake and transport, geologic distribution in surface and subsurface sediments, and ground-water impacts. The long-term use of U-Pond and the Z-19 Ditch has resulted in the localized accumulation of transuranic and fission product inventories as a result of sorption and filtration of particulates onto the uppermost sediments.

  19. Fluid-structure interaction by the mixed SPH-FE method with application to aircraft ditching

    Directory of Open Access Journals (Sweden)

    P Groenenboom

    2016-10-01

    Full Text Available This paper deals with numerical simulation of fluid-structure interaction as it occurs during aircraft ditching – an emergency condition where an aircraft is forced to land on water. The work is motivated by the requirement for aircraft manufactures to analyze ditching as part of the aircraft certification process requested by airworthiness authorities. The strong interaction of highly non-linear fluid flow phenomena and structural responses requires a coupled solution of this transient problem. Therefore, an approach coupling Smoothed Particle Hydrodynamics and the Finite Element method within the commercial, explicit software Virtual Performance Solutions has been pursued. In this paper, several innovative features are presented, which allow for accurate and efficient solution. Finally, exemplary numerical results are successfully compared to experimental data from a unique test campaign of guided ditching tests at quasi-full scale impact conditions. It may be concluded that through the application of state-of-the-art numerical techniques it has become possible to simulate the coupled fluidstructure interaction as occurring during ditching. Therefore, aircraft manufacturers may significantly benefit from numerical analysis for design and certification purposes.

  20. Magnetometric prospection of various types of large ditch enclosures (or fortifications) in Bohemia

    Czech Academy of Sciences Publication Activity Database

    Křivánek, Roman

    2003-01-01

    Roč. 41, - (2003), s. 216-219 ISSN 0066-5924. [Archaeological Prospection. Kraków, 10.09.2003-14.09.2003] R&D Projects: GA ČR GV404/97/K024 Institutional research plan: CEZ:AV0Z8002910 Keywords : ditch enclosure * magnetometric prospection * fortification Subject RIV: AC - Archeology, Anthropology, Ethnology

  1. Magnetometric prospection of various types of large ditched enclosures in Bohemia

    Czech Academy of Sciences Publication Activity Database

    Křivánek, Roman

    2006-01-01

    Roč. 13, č. 1 (2006), s. 25-43 ISSN 1075-2196 R&D Projects: GA ČR GV404/97/K024 Institutional research plan: CEZ:AV0Z80020508 Keywords : prospection * ditch enclosure * magnetometer Subject RIV: AC - Archeology, Anthropology, Ethnology

  2. 216-U-10 Pond and 216-Z-19 Ditch characterization studies

    International Nuclear Information System (INIS)

    Last, G.V.; Duncan, D.W.; Graham, M.J.; Hall, M.D.; Hall, V.W.; Landeen, D.S.; Leitz, J.G.; Mitchell, R.M.

    1994-02-01

    The chemical, reprocessing of spent nuclear fuels at the US Department of Energy's Hanford Site has generated large volumes of radioactive liquid effluents. The majority of these effluents have been used strictly for cooling or other supportive functions and have been discharged to ditches and ponds. The 216-U-10 Pond and 216-Z-19 Ditch are two such disposal facilities. These facilities are components of an integrated system of ditches, ponds, and overflow facilities collectively referred to as the U-Pond disposal system. The U-Pond system has been used since 1943 and has received a large variety of radioisotopes from several sources. This study covered tho major aspects of the environment, including wind resuspension, biological uptake and transport, geologic distribution in surface and subsurface sediments, and ground-water impacts. The long-term use of U-Pond and the Z-19 Ditch has resulted in the localized accumulation of transuranic and fission product inventories as a result of sorption and filtration of particulates onto the uppermost sediments

  3. Effects of lambda-cyhalothrin in two ditch microcosm systems of different trophic status

    NARCIS (Netherlands)

    Roessink, I.; Arts, G.H.P.; Belgers, J.D.M.; Bransen, F.F.J.; Maund, S.J.; Brock, T.C.M.

    2005-01-01

    The fate and effects of the pyrethroid insecticide lambda-cyhalothrin were compared in mesotrophic (macrophyte-dominated) and eutrophic (phytoplankton-dominated) ditch microcosms (0.5 m3). Lambda-cyhalothrin was applied three times at one-week intervals at concentrations of 10, 25, 50, 100, and 250

  4. Drainage filters and constructed wetlands to mitigate site-specific nutrient losses

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Hoffmann, Carl Christian; Iversen, Bo Vangsø

    Despite substantial efforts, the leaching of nutrients from agricultural land is still a serious and costly environmental problem in Denmark and elsewhere. The quality goals of the European Water Framework Directive (WFD) for the aquatic environment require a substantial reduction of diffuse nutr...... drainage. The project studies different approaches of implementing the filter technologies including drainage well or drainage pipe filters as well as surface-flow and sub-surface flow constructed wetlands....

  5. Percutaneous drainage of lung abscesses

    International Nuclear Information System (INIS)

    van Sonnenberg, E.; D'Agostino, H.; Casola, G.; Vatney, R.R.; Wittich, G.R.; Harker, C.

    1989-01-01

    The authors performed percutaneous drainage of lung abscesses in 12 patients. Indications for drainage were septicemia and persistence or worsening of radiographic findings. These lung abscesses were refractory to intravenous antibiotics and to bronchial toilet. Etiology of the abscesses included pneumonia (most frequently), trauma, postoperative development, infected necrotic neoplasm, and infected sequestration. Guidelines for drainage included passage of the catheter through contiguously abnormal lung and pleura, inability of the patient to cough, and/or bronchial obstruction precluding bronchial drainage. Cure was achieved in 11 of 12 patients. Catheters were removed on an average of 16 days after insertion. Antibiotics were administered an average of 18 days before drainage. No major complications occurred

  6. Acid mine drainage

    Science.gov (United States)

    Bigham, Jerry M.; Cravotta, Charles A.

    2016-01-01

    Acid mine drainage (AMD) consists of metal-laden solutions produced by the oxidative dissolution of iron sulfide minerals exposed to air, moisture, and acidophilic microbes during the mining of coal and metal deposits. The pH of AMD is usually in the range of 2–6, but mine-impacted waters at circumneutral pH (5–8) are also common. Mine drainage usually contains elevated concentrations of sulfate, iron, aluminum, and other potentially toxic metals leached from rock that hydrolyze and coprecipitate to form rust-colored encrustations or sediments. When AMD is discharged into surface waters or groundwaters, degradation of water quality, injury to aquatic life, and corrosion or encrustation of engineered structures can occur for substantial distances. Prevention and remediation strategies should consider the biogeochemical complexity of the system, the longevity of AMD pollution, the predictive power of geochemical modeling, and the full range of available field technologies for problem mitigation.

  7. Analysis of three-dimensional transient seepage into ditch drains ...

    Indian Academy of Sciences (India)

    Ratan Sarmah

    waterlogged soils in many regions of the world, including. India [2, 6–9]—to name a ... predicting two-dimensional seepage into a network of ...... when d1 ¼ 0, the lower limits of integration of the integral ...... and agricultural development. Irrig.

  8. Drained peatlands used for extraction and agriculture: biogeochemical status with special attention to greenhouse gas fluxes and rewetting

    Science.gov (United States)

    Sirin, Andrey; Chistotin, Maxim; Suvorov, Gennady; Glagolev, Mikhail; Kravchenko, Irina; Minaeva, Tatiana

    2010-05-01

    Many peatlands previously drained for peat extraction or utilized for agriculture (directly or after partial cutoff) are left abandoned during last decades in Europe, and especially in its eastern part. In the European part of Russia alone, several million hectares of peatlands have been modified for peat extraction and agriculture by direct water level draw-down and nowadays are not under use by economic reasons. This makes up one of the most serious and urgent problems of wise use and management of peatlands in these regions with serious feedback to people, environment and economy (Quick Scan of Peatlands in Central and Eastern Europe, 2009). Drainage for agriculture leads to peat oxidation resulting in substantial emissions of greenhouse gases (carbon dioxide and sometimes nitrous oxide) to the atmosphere. Together with peat fires this is the most significant negative input of peatland degradation to climate change (Assessment on Peatlands Biodiversity and Climate Change, 2008; Peatlands and Climate Change, 2008). Besides that, dehydrated peatlands often release methane. Starting from 2003, the effect of drainage and subsequent utilization of peatlands on the emissions of carbon dioxide and methane was studied in Tomsk region (West Siberia) during the summer-fall periods (Glagolev et al. 2008). The measurements were conducted by chamber method at peatlands drained for use as croplands (now partly being fallows) and peat cutting (currently abandoned or reclaimed for forest planting, haying, or pasturing), as well as at a wide range of undrained oligotrophic, mesotrophic, and eutrophic mires and burnt mire areas of different regeneration stages. The statistical analysis of data from a large number of study sites indicated a higher release of carbon dioxide from disturbed peatlands compared to undrained ones. At the same time some drained peatlands had considerable methane emission rates, additionally enhanced by the intensive efflux from the surface of drainage

  9. Land drainage strategies to cope with climate change in the Netherlands

    NARCIS (Netherlands)

    Ritzema, H.P.; Stuyt, L.C.P.M.

    2015-01-01

    Since the Middle Ages the Dutch have reclaimed many lakes and parts of the sea, creating polders. Drainage is required to use the land: for the inhabitants, for agriculture and for nature. Traditionally drainage was by gravity: through open (and later pipe) drains excess rainfall was transferred

  10. Drainage filter technologies to mitigate site-specific phosphorus losses

    DEFF Research Database (Denmark)

    Kjærgaard, Charlotte; Heckrath, Goswin Johann; Iversen, Bo Vangsø

    2014-01-01

    -specific nutrient losses in drainage. The “SUPREME-TECH” project (2010-2015), funded by the Danish Strategic Research Council, aims at providing the scientific basis for developing cost-effective drainage filter technologies to retain P in agricultural drainage waters. The project studies different approaches...... high risks areas of P loss and applying site-specific measures therefore seems a more cost-efficient approach. The Danish Commission for Nature and Agriculture has now called for a shift of paradigm towards targeted mitigation and development of new, cost-efficient technologies to mitigate site......-scale surface-flow constructed wetland. In the former, various natural and industrial P filter substrates have been tested for their ability to reduce inlet P concentrations to below environmental threshold values (

  11. Parcellaires fossoyés du Haut Empire des plateaux de Brie : Jossigny/Serris et Moissy-Cramayel (Seine-et-Marne. Approche méthodologique de l'étude des réseaux Ditch-marked land division from the Early Roman Empire, the Brie plateau: Jossigny/Serris and Moissy-Cramayel (Seine-et-Marne. Methodological approach to the study of networks

    Directory of Open Access Journals (Sweden)

    Gilles Desrayaud

    2009-05-01

    such reticulated systems were laid during the end of the Ist C. BC or the 1st half of the Ist C. AD. The occupied areas and the ditches were abandoned during the IIIrd C. AD. Those ditches, for the most part rectilinear and sometimes several hundred meters in length, could fulfill the triple function of drainage, land division and enclosure boundaries. Their morphologies along with their pedological and topographic contexts seem to imply a will to drain the surrounding soils, which may be linked to land cultivation. A methodology has been developed to study the orientation and positions of presupposed axes of linear features (ditches, walls, pathways..., leading to a hypothosis of contemporaneous “orthogonal” groupings. Statistical and comparative studies on the possible presence of distance and surface modules were also carried out. It appears that the surfaces of “orthogonal” delineated areas might have been determined on the basis of modules corresponding to or approaching units known from Antiquity. For both sites, those elements seem to represent strong indications as to the presence of an agricultural drainage and land dividing system, based at least partly on an orthogonal grid and fixed surface units.

  12. Water pollution by agriculture

    OpenAIRE

    Moss, Brian

    2007-01-01

    Agriculture disrupts all freshwater systems hugely from their pristine states. The former reductionist concept of pollution was of examining individual effects of particular substances on individual taxa or sub-communities in freshwater systems, an essentially ecotoxicological concept. It is now less useful than a more holistic approach that treats the impacts on the system as a whole and includes physical impacts such as drainage and physical modification of river channels and modification o...

  13. The Effect of Camber Bed Drainage Landforms on Soil Nutrient ...

    African Journals Online (AJOL)

    The Vertisols of the Accra Plains of Ghana are water logged after significant rainfall due to the low-lying topography (0.1-1 %). Camber bed (Cb) drainage landforms have been developed at the Agricultural Research Centre, Kpong, for draining off excess water. Field experiments were conducted to verify if maize growth and ...

  14. Downstream approaches to phosphorus management in agricultural landscapes: regional applicability and use.

    Science.gov (United States)

    Kröger, R; Dunne, E J; Novak, J; King, K W; McLellan, E; Smith, D R; Strock, J; Boomer, K; Tomer, M; Noe, G B

    2013-01-01

    This review provides a critical overview of conservation practices that are aimed at improving water quality by retaining phosphorus (P) downstream of runoff genesis. The review is structured around specific downstream practices that are prevalent in various parts of the United States. Specific practices that we discuss include the use of controlled drainage, chemical treatment of waters and soils, receiving ditch management, and wetlands. The review also focuses on the specific hydrology and biogeochemistry associated with each of those practices. The practices are structured sequentially along flowpaths as you move through the landscape, from the edge-of-field, to adjacent aquatic systems, and ultimately to downstream P retention. Often practices are region specific based on geology, cropping practices, and specific P related problems and thus require a right practice, and right place mentality to management. Each practice has fundamental P transport and retention processes by systems that can be optimized by management with the goal of reducing downstream P loading after P has left agricultural fields. The management of P requires a system-wide assessment of the stability of P in different biogeochemical forms (particulate vs. dissolved, organic vs. inorganic), in different storage pools (soil, sediment, streams etc.), and under varying biogeochemical and hydrological conditions that act to convert P from one form to another and promote its retention in or transport out of different landscape components. There is significant potential of hierarchically placing practices in the agricultural landscape and enhancing the associated P mitigation. But an understanding is needed of short- and long-term P retention mechanisms within a certain practice and incorporating maintenance schedules if necessary to improve P retention times and minimize exceeding retention capacity. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Tile Drainage Expansion Detection using Satellite Soil Moisture Dynamics

    Science.gov (United States)

    Jacobs, J. M.; Cho, E.; Jia, X.

    2017-12-01

    In the past two decades, tile drainage installation has accelerated throughout the Red River of the North Basin (RRB) in parts of western Minnesota, eastern North Dakota, and a small area of northeastern South Dakota, because the flat topography and low-permeability soils in this region necessitated the removal of excess water to improve crop production. Interestingly, streamflow in the Red River has markedly increased and six of 13 major floods during the past century have occurred since the late 1990s. It has been suggested that the increase in RRB flooding could be due to change in agricultural practices, including extensive tile drainage installation. Reliable information on existing and future tile drainage installation is greatly needed to capture the rapid extension of tile drainage systems and to locate tile drainage systems in the north central U.S. including the RRB region. However, there are few reliable data of tile drainage installation records, except tile drainage permit records in the Bois de Sioux watershed (a sub-basin in southern part of the RRB where permits are required for tile drainage installation). This study presents a tile drainage expansion detection method based on a physical principle that the soil-drying rate may increase with increasing tile drainage for a given area. In order to capture the rate of change in soil drying rate with time over entire RRB (101,500 km2), two satellite-based microwave soil moisture records from the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) and AMSR2 were used during 2002 to 2016. In this study, a sub-watershed level (HUC10) potential tile drainage growth map was developed and the results show good agreement with tile drainage permit records of six sub-watersheds in the Bois de Sioux watershed. Future analyses will include improvement of the potential tile drainage map through additional information using optical- and thermal-based sensor products and evaluation of its

  16. Mosquitoes Associated with Ditch-Plugged and Control Tidal Salt Marshes on the Delmarva Peninsula

    Directory of Open Access Journals (Sweden)

    Paul T. Leisnham

    2011-07-01

    Full Text Available A study was conducted during the summer of 2009 (from July to September to characterize mosquito communities among different habitats in five historically ditched tidal salt marshes and three adjacent wooded areas in the E.A. Vaughn Wetland Management Area on the Maryland Delmarva Peninsula, USA. Study marshes are characteristic of Atlantic coastal salt marshes that had undergone grid ditching from the 1930s to 1950s. In the autumn of 2008 (October and November ditches were plugged near their outlets in two (‘experimental’ marshes with the aim to restore their natural tidal hydrology. The three other marshes were not plugged. Marshes were sampled from July to September in 2009 by using standard dip count method. A total of 2,457 mosquito larvae representing six species were collected on 15.4% (86/557 of all sample occasions and 399 adults representing four mosquito species were collected from landing counts. Aedes sollicitans, Anopheles bradleyi and Culex salinarius were the most common species collected in larval habitats, and Ae. sollicitans was the most common adult collected. Wooded habitats had more total mosquitoes, were also more frequently occupied by mosquitoes and had higher densities of mosquitoes than marsh habitats. Almost all larvae collected from marshes were from one experimental and one control site. The majority of larvae at the control site were Ae. sollicitans in marsh pannes while Cx. salinarius, An. bradleyi, Ae. cantator, and Ae. sollicitans were collected in high numbers from ditches at the experimental site. We found a difference in the proportion of marsh pannes occupied by Ae. sollicitans but not total mosquitoes sampled 4–5 days after spring tide events than on other occasions. Salinity measures of 42 larval habitats showed lower median salinity in mosquito-occupied habitats (11.5 ppt than unoccupied habitats (20.1 ppt, and in habitats in wooded areas followed by ditches and pannes in marsh areas. The results of

  17. Sensitivity analysis in oxidation ditch modelling: the effect of variations in stoichiometric, kinetic and operating parameters on the performance indices

    NARCIS (Netherlands)

    Abusam, A.A.A.; Keesman, K.J.; Straten, van G.; Spanjers, H.; Meinema, K.

    2001-01-01

    This paper demonstrates the application of the factorial sensitivity analysis methodology in studying the influence of variations in stoichiometric, kinetic and operating parameters on the performance indices of an oxidation ditch simulation model (benchmark). Factorial sensitivity analysis

  18. Hydro-geochemistry and retention of phosphorus in drainage filters and constructed wetlands

    DEFF Research Database (Denmark)

    Canga, Eriona; Kjærgaard, Charlotte; Iversen, Bo Vangsø

    Research Council, aims at providing the scientific basis for developing cost-effective filter technologies targeting P-retention and N-removal in agricultural subsurface drainage. The project studies different approaches of implementing the filter technologies including drainage well filters as well...... typically applied to point sources. This calls for a shift of paradigm towards the development of new, cost-efficient technologies to mitigate site-specific nutrient losses in drainage. A newly launched Danish research project “SUPREME-TECH” (2010-2015) (www.supreme-tech.dk) funded by the Danish Strategic...... in drainage water to below environmental threshold values (

  19. How were the ditches filled? Sedimentological and micromorphological classification of formation processes within graben-like archaeological objects

    Czech Academy of Sciences Publication Activity Database

    Lisá, Lenka; Komoróczy, Balázs; Vlach, Marek; Válek, M.; Bajer, A.; Kovárník, J.; Rajtár, J.; Hüssen, C.-M.; Šumberová, Radka

    2015-01-01

    Roč. 370, 3 June (2015), s. 66-76 ISSN 1040-6182 Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M300011201 Program:M Institutional support: RVO:67985831 ; RVO:68081758 ; RVO:67985912 Keywords : formation processes * micromorphology * Neolithic rondel structures * Roman ditch * sedimentology * V-shaped ditch Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 2.067, year: 2015

  20. The ditches of México City and implications on residential buildings of the XVIII century

    Directory of Open Access Journals (Sweden)

    Alejandro Jimenez Vaca

    2015-08-01

    Full Text Available Known for its canals or by its designation in the New Spain as ditches, the image of aquatic city of Mexico City was widespread in the world. It would seem that those romantic references of the city had been left alone in the lines written by the chroniclers, but when analyzing architectural plans and current cadastral can glimpse vestiges of this lakeside past. This research is done by analyzing eigh-teenth century plans, through identification of ex-isting ditches in Mexico City during this period, and its current trajectory in a plane, performing both an analysis of their influence on residential architecture, determining the characteristics of the houses in the path of the canals, by classifying canal houses, depending on the level of relationship between these two constructive general.

  1. Effect of operational cycle time length on nitrogen removal in an alternating oxidation ditch system.

    Science.gov (United States)

    Mantziaras, I D; Stamou, A; Katsiri, A

    2011-06-01

    This paper refers to nitrogen removal optimization of an alternating oxidation ditch system through the use of a mathematical model and pilot testing. The pilot system where measurements have been made has a total volume of 120 m(3) and consists of two ditches operating in four phases during one cycle and performs carbon oxidation, nitrification, denitrification and settling. The mathematical model consists of one-dimensional mass balance (convection-dispersion) equations based on the IAWPRC ASM 1 model. After the calibration and verification of the model, simulation system performance was made. Optimization is achieved by testing operational cycles and phases with different time lengths. The limits of EU directive 91/271 for nitrogen removal have been used for comparison. The findings show that operational cycles with smaller time lengths can achieve higher nitrogen removals and that an "equilibrium" between phase time percentages in the whole cycle, for a given inflow, must be achieved.

  2. Quarterly sampling of the wetlands along the old F-Area effluent ditch: March 1994

    International Nuclear Information System (INIS)

    Dixon, K.L.; Cummins, C.L.; Rogers, V.A.

    1994-05-01

    In March 1994, well point water and near surface water (bucket) samples were collected to further characterize tritium and volatile organic compounds (VOC) in the wetlands along the old F-Area effluent ditch south of 643-E (old burial ground). Groundwater flow paths suggest that compounds detected in water table wells around 643-E would migrate towards the old F-Area effluent ditch and Fourmile Branch. Recent analytical results from near surface water sampling in the wetlands that comprise the old F-Area effluent ditch have shown that tritium and small quantities of VOCs are outcropping in the area. Results of the March 1994 sampling event further support findings that tritium and volatile organic compounds originating from 643-E are outcropping in the wetlands near the old F-Area effluent ditch. Six different analytes were detected in the well points at least once at concentrations greater than the method detection limit: d 1,2-dichloroethylene, acetone, methyl ethyl ketone, tetrachloroethylene, trichloroethylene, and tritium. 1,2-dichloroethylene, tetrachloroethylene, trichloroethylene, and tritium were detected at levels above Primary Drinking Water Standards or Maximum Contaminant Levels list. Four analytes, 1,2-dichloroethylene, trichloroethylene, tritium, and vinyl chloride, were detected at least once at concentrations greater than the method detection limit and least once at concentrations above the PDWS or the MCL. Based on differences in tritium concentrations at each location, it was determined that the sampling devices intercepted different groundwater flow paths. This negated direct comparison of analytical results between devices. However, when VOC concentrations measured at each well point and bucket location were normalized, resulting well point and bucket VOC concentrations were comparable in most cases. These results suggest that volatilization losses of VOCs from the buckets were negligible

  3. Quarterly sampling of the wetlands along the old F Area effluent ditch: August 1994

    International Nuclear Information System (INIS)

    Cummins, C.L.; Dixon, K.L.

    1994-08-01

    In August 1994, well point water and near-surface water samples were collected to characterize tritium and volatile organic compounds (VOC) in the wetlands along the old F-Area effluent ditch south of 643-E (old burial ground). The August sampling event was the third in a series of eight events. Groundwater flow paths suggest that compounds detected in water table wells around 643-E migrate towards the old F-Area effluent ditch and Fourmile Branch. Recent analytical results from well point and near-surface water sampling in the wetlands that comprise the old F-Area effluent ditch have shown that tritium and small quantities of VOCs are outcropping in the area. For this study, seven locations along the old F-Area effluent ditch were selected to be sampled. Well point samples were collected from all seven locations and near-surface water samples were collected at four locations. A secondary objective of this project was to compare VOC concentrations between the well points installed to depths of 6 to 8 ft and the near-surface water sampling buckets installed to depths of 1 to 2 ft. Based on differences in tritium concentrations at each location, it was determined that the sampling devices intercepted different groundwater flow paths. This negated direct comparison of analytical results between devices. However, when VOC concentrations measured at each well point and bucket location were normalized, based on the percent differences observed in tritium concentrations at that location, the resulting well point and bucket VOC concentrations were comparable in most cases. These results are consistent with the results from the three previous sampling events, and suggest that volatilization losses of VOCs from the buckets may be negligible. Since the results from the two sampling methodologies are not directly comparable, further sampling of the buckets is not planned

  4. [Molluscicidal effect of film on ditches in mountainous schistosomiasis endemic regions].

    Science.gov (United States)

    Zhu, Hong-Qing; Zhong, Bo; Zhang, Gui-Rong; Tang, Shu-Gui; Cao, Chun-Li; Zhang, Xu-Dong; Jia, Bin; Zhang, Yi; Li, Jian-Guo; Fu, Tao; Chen, Lin; Lu, Ding; Bao, Zi-Ping

    2011-04-01

    To evaluate the molluscicidal effect of film on ditches in mountainous schistosomiasis endemic regions. A ditch with Oncomelania hupensis snails was selected as experimental field. The ditch was divided into 3 parts (groups): a niclosamide plus film covering group (film covering after spraying by wettable powder of 50% niclosamide ethanolamine salt upon 2 g/m2), a film covering group (film covering directly without niclosamide spraying), and a control group (no molluscicidal measures). The snail investigation was performed 7, 10, 40, 60 d and 90 d after film covering. The temperatures outside and inside film were determined twice a day during the experiment. The temperature inside the film was significantly higher than that outside the film (t = 4.12, P film in the niclosamide plus film covering group and film covering group respectively; 96.58% and 93.06% ten days post-film respectively; both 100% forty days post-film. The multi-factor regression model indicated that covering film with niclosamide applying, extending film covering time, and increasing cumulate temperature inside film could enhance the molluscicidal effect. The film covering has well molluscicidal effect. The molluscicidal effect of covering film with niclosamide is better than that of covering film alone in short time. However, the covering film alone also has good molluscicidal effect when increasing covering time.

  5. Sustainable Drainage Systems

    Directory of Open Access Journals (Sweden)

    Miklas Scholz

    2015-05-01

    Full Text Available Urban water management has somewhat changed since the publication of The Sustainable Drainage System (SuDS Manual in 2007 [1], transforming from building traditional sewers to implementing SuDS, which are part of the best management practice techniques used in the USA and seen as contributing to water-sensitive urban design in Australia. Most SuDS, such as infiltration trenches, swales, green roofs, ponds, and wetlands, address water quality and quantity challenges, and enhance the local biodiversity while also being acceptable aesthetically to the public. Barriers to the implementation of SuDS include adoption problems, flood and diffuse pollution control challenges, negative public perception, and a lack of decision support tools addressing, particularly, the retrofitting of these systems while enhancing ecosystem services. [...

  6. Habitat-specific morphological variation among threespine sticklebacks (Gasterosteus aculeatus within a drainage basin.

    Directory of Open Access Journals (Sweden)

    Mike M Webster

    Full Text Available Habitat-specific morphological variation, often corresponding to resource specialization, is well documented in freshwater fishes. In this study we used landmark based morphometric analyses to investigate morphological variation among threespine sticklebacks (Gasterosteus aculeatus L. from four interconnected habitat types within a single lowland drainage basin in eastern England. These included the upper and lower reaches of the river, the estuary, a connected ditch network and a coastal salt marsh. We found significant habitat-specific differences in morphology, with three axes of variation describing differences in orbit diameter, body depth, caudal peduncle shape and pectoral fin positioning as well as variation in relative dorsal and pelvic spine size. Interestingly, the ditch system, an artificial and heavily managed habitat, is populated by sticklebacks with a characteristic morphology, suggesting that human management of habitats can in some circumstances lead to morphological variation among the animals that inhabit them. We discuss the mechanisms that conceivably underlie the observed morphological variation and the further work necessary to identify them. Finally, we consider the implications of habitat-specific body shape variation for the behavioural ecology of this ecologically generalist species.

  7. Habitat-Specific Morphological Variation among Threespine Sticklebacks (Gasterosteus aculeatus) within a Drainage Basin

    Science.gov (United States)

    Webster, Mike M.; Atton, Nicola; Hart, Paul J. B.; Ward, Ashley J. W.

    2011-01-01

    Habitat-specific morphological variation, often corresponding to resource specialization, is well documented in freshwater fishes. In this study we used landmark based morphometric analyses to investigate morphological variation among threespine sticklebacks (Gasterosteus aculeatus L.) from four interconnected habitat types within a single lowland drainage basin in eastern England. These included the upper and lower reaches of the river, the estuary, a connected ditch network and a coastal salt marsh. We found significant habitat-specific differences in morphology, with three axes of variation describing differences in orbit diameter, body depth, caudal peduncle shape and pectoral fin positioning as well as variation in relative dorsal and pelvic spine size. Interestingly, the ditch system, an artificial and heavily managed habitat, is populated by sticklebacks with a characteristic morphology, suggesting that human management of habitats can in some circumstances lead to morphological variation among the animals that inhabit them. We discuss the mechanisms that conceivably underlie the observed morphological variation and the further work necessary to identify them. Finally, we consider the implications of habitat-specific body shape variation for the behavioural ecology of this ecologically generalist species. PMID:21698269

  8. adequacy of drainage channels f drainage channels in a small

    African Journals Online (AJOL)

    eobe

    The area upon which waterfalls and the netw through ... ls were determined using the rational model and manning's equation. A .... runoff, including roads, culverts and drainage systems. ... hence, detailed design information of the drain is.

  9. Percutaneous drainage of lung abscess

    Energy Technology Data Exchange (ETDEWEB)

    Ri, Jong Min; Kim, Yong Joo; Kang, Duk Sik [Kyung-Pook National University Hospital, Daegu (Korea, Republic of)

    1992-05-15

    Medical treatment using antibiotics and postural drainage has been widely adopted as a treatment method of pulmonary abscess, accompanied by surgical methods in cases intractable to drug therapy. However long-term therapy may be required, and the tolerance of organisms to antibiotics or other complications are apt to be encountered, during medical treatment. To shorten the convalescent period or to decrease the risk of invasive procedures, rather simple and relatively easy interventional techniques such as transbronchial or percutaneous catheter drainage have been successfully tried. We have performed 12 cases of percutaneous drainages of lung abscesses under fluoroscope guidance. This report is on the results of this procedure.

  10. Percutaneous drainage of lung abscess

    International Nuclear Information System (INIS)

    Ri, Jong Min; Kim, Yong Joo; Kang, Duk Sik

    1992-01-01

    Medical treatment using antibiotics and postural drainage has been widely adopted as a treatment method of pulmonary abscess, accompanied by surgical methods in cases intractable to drug therapy. However long-term therapy may be required, and the tolerance of organisms to antibiotics or other complications are apt to be encountered, during medical treatment. To shorten the convalescent period or to decrease the risk of invasive procedures, rather simple and relatively easy interventional techniques such as transbronchial or percutaneous catheter drainage have been successfully tried. We have performed 12 cases of percutaneous drainages of lung abscesses under fluoroscope guidance. This report is on the results of this procedure

  11. Effect of increased utilization of wetland for peat harvesting and forest drainage on employment

    Energy Technology Data Exchange (ETDEWEB)

    Carlen, O; Muller, A

    1984-01-01

    Wetlands cover 15 percent of the area of Sweden. Most of it is peatland and part of it supports forest growth. The prognosis of peat production and ditching for drainage is based upon economical evaluations. A questioning of peat producers has also been performed. Two prognoses have been made for the effect of peat fuel production on the employment. By 1990 about 800 man-years were expected. On the advent of government subsidies to peat fuelled plants, about 1000 more jobs were expected. Unemployment and coal fuelled plants as an alternative are understood by implication. Indirect effects are expected among equipment manufacturers amounting to 50-100 yearly workers. Draining of forests and peat-lands will take 124 man-years as a minimum by 1990 and about 200 more if there will be financial assistance.

  12. Peritoneal Drainage Versus Pleural Drainage After Pediatric Cardiac Surgery.

    Science.gov (United States)

    Gowda, Keshava Murty Narayana; Zidan, Marwan; Walters, Henry L; Delius, Ralph E; Mastropietro, Christopher W

    2014-07-01

    We aimed to determine whether infants undergoing cardiac surgery would more efficiently attain negative fluid balance postoperatively with passive peritoneal drainage as compared to traditional pleural drainage. A prospective, randomized study including children undergoing repair of tetralogy of Fallot (TOF) or atrioventricular septal defect (AVSD) was completed between September 2011 and June 2013. Patients were randomized to intraoperative placement of peritoneal catheter or right pleural tube in addition to the requisite mediastinal tube. The primary outcome measure was fluid balance at 48 hours postoperatively. Variables were compared using t tests or Fisher exact tests as appropriate. A total of 24 patients were enrolled (14 TOF and 10 AVSD), with 12 patients in each study group. Mean fluid balance at 48 hours was not significantly different between study groups, -41 ± 53 mL/kg in patients with periteonal drainage and -9 ± 40 mL/kg in patients with pleural drainage (P = .10). At 72 hours however, postoperative fluid balance was significantly more negative with peritoneal drainage, -52.4 ± 71.6 versus +2.0 ± 50.6 (P = .04). On subset analysis, fluid balance at 48 hours in patients with AVSD was more negative with peritoneal drainage as compared to pleural, -82 ± 51 versus -1 ± 38 mL/kg, respectively (P = .02). Fluid balance at 48 hours in patients with TOF was not significantly different between study groups. Passive peritoneal drainage may more effectively facilitate negative fluid balance when compared to pleural drainage after pediatric cardiac surgery, although this benefit is not likely universal but rather dependent on the patient's underlying physiology. © The Author(s) 2014.

  13. Surface water drainage system. Environmental assessment and finding of no significant impact

    International Nuclear Information System (INIS)

    1996-05-01

    This Environmental Assessment (EA) is written pursuant to the National Environmental Policy Act (NEPA). The document identifies and evaluates the action proposed to correct deficiencies in, and then to maintain, the surface water drainage system serving the Department of Energy's Rocky Flats Environmental Technology Site (Site), located north of Golden, Colorado. Many of the activities proposed would not normally be subject to this level of NEPA documentation. However, in many cases, maintenance of the system has been deferred to the point that wetlands vegetation has become established in some ditches and culverts, creating wetlands. The proposed activities would damage or remove some of these wetlands in order to return the drainage system to the point that it would be able to fully serve its intended function - stormwater control. The Department of Energy (DOE) regulations require that activities affecting environmentally sensitive areas like wetlands be the subject of an EA. Most portions of the surface water drainage system are presently inadequate to convey the runoff from a 100-year storm event. As a result, such an event would cause flooding across much of the Site and possibly threaten the integrity of the dams at the terminal ponds. Severe flooding would not only cause damage to facilities and equipment, but could also facilitate the transport of contaminants from individual hazardous substance sites (IHSSs). Uncontrolled flow through the A- and B-series ponds could cause contaminated sediments to become suspended and carried downstream. Additionally, high velocity flood flows significantly increase erosion losses

  14. 216-A-29 Ditch supplemental information to the Hanford Facility Contingency Plan (DOE/RL-93-75)

    International Nuclear Information System (INIS)

    Ingle, S.J.

    1996-05-01

    This document is a unit-specific contingency plan for the 216-A-29 Ditch and is intended to be used as a supplement to DOE/RL-93-75, Hanford Facility Contingency Plan (DOE-RL 1993). This unit-specific plan is to be used to demonstrate compliance with the contingency plan requirements of the Washington Administrative Code, Chapter 173- 303 for certain Resource Conservation and Recovery Act of 1976 waste management units. The 216-A-29 Ditch is a surface impoundment that received nonregulated process and cooling water and other dangerous wastes primarily from operations of the Plutonium/Uranium Extraction Plant. Active between 1955 and 1991, the ditch has been physically isolated and will be closed. Because it is no longer receiving discharges, waste management activities are no longer required at the unit. The ditch does not present a significant hazard to adjacent units, personnel, or the environment. It is unlikely that any incidents presenting hazards to public health or the environment would occur at the 216-A-29 Ditch

  15. Evaluation of Critical Parameters to Improve Slope Drainage System

    Directory of Open Access Journals (Sweden)

    Yong Weng Long

    2017-01-01

    Full Text Available This study focuses on identifying and evaluating critical parameters of various drainage configurations, arrangement, and filter which affect the efficiency of water draining system in slopes. There are a total of seven experiments with different types of homogeneous soil, drainage envelope, filter material, and quantity of pipes performed utilizing a model box with a dimension of 0.8 m × 0.8 m × 0.6 m. The pipes were orientated at 5 degrees from the horizontal. Rainfall event was introduced via a rainfall simulator with rainfall intensity of 434.1 mm/h. From the experiments performed, the expected outcomes when utilizing double pipes and geotextile as envelope filter were verified in this study. The results obtained from these experiments were reviewed and compared with Chapter 14 “Subsurface Drainage Systems” of DID’s Irrigation and Agricultural Drainage Manual of Malaysia and the European standard. It is recommended that the pipe installed in the slope could be wrapped with geotextile and in tandem with application of granular filter to minimize clogging without affecting the water discharge rate. Terzaghi’s filter criteria could be followed closely when deciding on new materials to act as aggregate filter. A caging system could be introduced as it could maintain the integrity of the drainage system and could ease installation.

  16. Nonsurgical drainage of splenic abscess

    International Nuclear Information System (INIS)

    Berkman, W.A.; Harris, S.A. Jr.; Bernardino, M.E.

    1983-01-01

    The mortality associated with intraabdominal abscess remains high despite modern surgical methods and antibiotics. Draingae of abscesses of the abdomen, retroperitoneum, pelvis, pancreatic pseudocyst, mediastinum, and lung may be treated effectively by percutaneous catheter placement. In several reports of percutaneous abdominal abscess drainage, only three cases of splenic abscess drainage have been reported. The authors have recently drained two splenic abscesses with the aid of computed tomography (CT) and emphasize several advantages of the percutaneous guided approach

  17. New data about the archaeological area of Marroquíes Bajos: the fifth ditch

    Directory of Open Access Journals (Sweden)

    Sánchez, Alberto

    2005-12-01

    Full Text Available The present paper presents the results that were obtained in the excavation carried out in the plot DOC-1 (SUNP-1 in the Archaeological Area of Marroquíes Bajos. The main contribution of this excavation in the context of all the research done in this archaeological area has to do with its Chalcolithic phase, in particular with the delimitation and documentation of the fifth ditch in an extension that was hitherto unknown. Along with this ditch, a fortified structure was also documented, which consisted of two walls and a semicircular hollow tower which was very likely to protect an entrance. Finally, the research has yielded the first data on the food and health of the people in this settlement by analysing a set of bone remains located on the bottom of the ditch.

    Este trabajo presenta los resultados obtenidos en la excavación realizada en la parcela DOC-1 (SUNP-1 de la Zona Arqueológica de Marroquíes Bajos. La principal aportación de la excavación al ámbito de las investigaciones desarrolladas en esta zona arqueológica se centra en su fase calcolítica, concretamente en la delimitación y documentación del quinto foso en una extensión no conocida hasta el momento. Asociado este foso se documentó igualmente una estructura fortificada compuesta por dos muros y una torre semicircular hueca que muy posiblemente protegía un acceso. Finalmente la investigación desarrollada a permitido obtener los primeros datos sobre alimentación y salud de la población del asentamiento mediante el análisis de un conjunto de restos óseos localizados en el fondo del foso.

  18. AN INNOVATIVE SYSTEM FOR BIOREMEDIATION OF AGRICULTURAL CHEMICALS FOR ENVIRONMENTAL SUSTAINABILITY

    Science.gov (United States)

    Agricultural chemicals (both inorganic and organic) in drainage discharge from watersheds have raised concerns about the quality of surface water resources. For example, hypoxia in the Gulf of Mexico has been related to the nutrients discharging from agricultural watersheds...

  19. Economic Development Mode and Countermeasure Research on the Nansi Lake Drainage Area Based on Circular Economy

    OpenAIRE

    Jia, Yong-fei; Peng, Li-min

    2011-01-01

    Firstly, it is pointed out that circular economy should be vigorously developed in the Nansi Lake Drainage Area, and the connotation of circular economy is expounded. Then, problems in developing circular economy in Nansi Lake Drainage Area are analyzed from the aspects of agriculture, industrial enterprises, and waste utilization. Finally, combining with the four modes of peasant household, enterprise, region and society in the development of circular economy, corresponding countermeasures a...

  20. Agriculture: Agriculture and Air Quality

    Science.gov (United States)

    Information on air emissions from agricultural practices, types of agricultural burning, air programs that may apply to agriculture, reporting requirements, and links to state and other federal air-quality information.

  1. Ditching Tests of a 1/10-Scale Model of the North American XFJ-1 Airplane Ted No. NACA 314

    Science.gov (United States)

    Fisher, Lloyd J.; McBride, Ellis E.

    1948-01-01

    Tests were made of a 1/10-scale dynamically similar model of the North American XFJ-1 airplane to study its behavior when ditched. The model was landed in calm water at the Langley tank no. 2 monorail. Various landing attitudes, speeds, and conditions of damage were simulated. The behavior of the model was determined from visual observations, by recording the accelerations, and by taking motion pictures of the ditchings. Data are presented in tabular form, sequence photographs, and time-history acceleration curves. From the results of the tests it was concluded that the airplane should be ditched at the near-stall, tail-down landing attitude of 12 deg. The flaps should be fully extended to obtain the lowest possible landing speed. The wing-tip tanks should be jettisoned if any appreciable load of fuel remains; if empty, they should be retained for additional buoyancy. In a calm-water ditching the airplane will probably run about 600 feet Maximum longitudinal decelerations of about 2.5g and maximum vertical acceleration of about 2g will be encountered. The nose-intake duct will be clear of the water until practically all forward motion has stopped.

  2. Data on three-year pesticide monitoring in ditches of the apple orchard region of Altes Land, Germany

    Directory of Open Access Journals (Sweden)

    Stefan Lorenz

    2018-06-01

    Full Text Available The data presented in this article are related to the research article 'Chemical and biological monitoring of the load of plant protection products and of zoocoenoses in ditches of the orchard region Altes Land' (Süß et al., 2006 [1], which is only available in the German language. The pesticide data presented here were acquired from four ditches (three ditches were located in apple orchards, and one ditch was located in a grassland region between 2001 and 2003 (Lorenz et al., 2018 [2]. Two different monitoring strategies were applied: event-driven sampling after pesticide applications and weekly integrated sampling using automatic water samplers. A total of 70 active substances were monitored while farmers applied 25 active substances. This article describes the study sites and the analytical methods used to quantify the pesticides in the water samples. The field data set is publicly available at the OpenAgrar repository under https://doi.org/10.5073/20180213-144359 (Lorenz et al., 2018 [2].

  3. China Report, Agriculture Hunan Agricultural Geography

    Science.gov (United States)

    1984-08-13

    small leaf li ji mu [1420 5509 2929 2606 4949 2606 Loropetalum chinense], black dye trees [Platycaria strobilacea], Chinese sweet gum [Liquidambar...conservancy projects, guar - anteeing of project safety, strengthening of management, and improvement of irrigation ditch utilization coefficients, in...for farm machines. In addition 214 Xiangtan, Liuyang, and Youxian counties produced some native pesticides, powdered phosphate, ammonium humic

  4. Long-Term Hydrologic Impacts of Controlled Drainage Using DRAINMOD

    Science.gov (United States)

    Saadat, S.; Bowling, L. C.; Frankenberger, J.

    2017-12-01

    Controlled drainage is a management strategy designed to mitigate water quality issues caused by subsurface drainage but it may increase surface ponding and runoff. To improve controlled drainage system management, a long-term and broader study is needed that goes beyond the experimental studies. Therefore, the goal of this study was to parametrize the DRAINMOD field-scale, hydrologic model for the Davis Purdue Agricultural Center located in Eastern Indiana and to predict the subsurface drain flow and surface runoff and ponding at this research site. The Green-Ampt equation was used to characterize the infiltration, and digital elevation models (DEMs) were used to estimate the maximum depressional storage as the surface ponding parameter inputs to DRAINMOD. Hydraulic conductivity was estimated using the Hooghoudt equation and the measured drain flow and water table depths. Other model inputs were either estimated or taken from the measurements. The DRAINMOD model was calibrated and validated by comparing model predictions of subsurface drainage and water table depths with field observations from 2012 to 2016. Simulations based on the DRAINMOD model can increase understanding of the environmental and hydrological effects over a broader temporal and spatial scale than is possible using field-scale data and this is useful for developing management recommendations for water resources at field and watershed scales.

  5. Groundwater pollution by nitrates in irrigated areas with drainage

    International Nuclear Information System (INIS)

    Chandio, B.M.; Azam, M.; Abdullah, M.

    2001-01-01

    Field studies were conducted at three selected sites in irrigated areas of Pakistan to assess magnitude and severity of groundwater pollution by nitrates. The results of these studies indicate that concentration of nitrates in most of the samples collected from irrigated areas having drainage facility is much lower than threshold limit. The nitrate-nitrogen level within drainage projects ranges from 0.01-9.00 mg/l and in the area without drainage system ranges from 10.1-12.5 mg/l. The mineral fertilizers though are making contribution of NO3-N to the groundwater sources but that is much lower than threshold limits. The presence of septic tanks or farmyard manure dumps is also significant contributors of NO3-N to the groundwater. Thus drinking water sources near these polluting points are probable danger to human health. It is, therefore, concluded that still there is a lot of potential for fertilizer use in the agriculture but proper drainage facilities should be provided to minimize the potential threat of NO/sub 3/ pollution. (author)

  6. in remediating acid mine drainage

    African Journals Online (AJOL)

    The management and treatment of contaminated mine water is one of the most urgent problems facing the South African mining industry. The cost advantage of permeable reactive barriers (PRBs) has seen their increased application as means of passively treating mine drainage. A PRB is built by placing a reactive material ...

  7. Field tracer investigation of unsaturated zone flow paths and mechanisms in agricultural soils of northwestern Mississippi, USA

    Science.gov (United States)

    Perkins, K.S.; Nimmo, J.R.; Rose, C.E.; Coupe, R.H.

    2011-01-01

    In many farmed areas, intensive application of agricultural chemicals and withdrawal of groundwater for irrigation have led to water quality and supply issues. Unsaturated-zone processes, including preferential flow, play a major role in these effects but are not well understood. In the Bogue Phalia basin, an intensely agricultural area in the Delta region of northwestern Mississippi, the fine-textured soils often exhibit surface ponding and runoff after irrigation and rainfall as well as extensive surface cracking during prolonged dry periods. Fields are typically land-formed to promote surface flow into drainage ditches and streams that feed into larger river ecosystems. Downward flow of water below the root zone is considered minimal; regional groundwater models predict only 5% or less of precipitation recharges the heavily used alluvial aquifer. In this study transport mechanisms within and below the root zone of a fallow soybean field were assessed by performing a 2-m ring infiltration test with tracers and subsurface monitoring instruments. Seven months after tracer application, 48 continuous cores were collected for tracer extraction to define the extent of water movement and quantify preferential flow using a mass-balance approach. Vertical water movement was rapid below the pond indicating the importance of vertical preferential flow paths in the shallow unsaturated zone, especially to depths where agricultural disturbance occurs. Lateral flow of water at shallow depths was extensive and spatially non-uniform, reaching up to 10. m from the pond within 2. months. Within 1. month, the wetting front reached a textural boundary at 4-5. m between the fine-textured soil and sandy alluvium, now a potential capillary barrier which, prior to extensive irrigation withdrawals, was below the water table. Within 10. weeks, tracer was detectable at the water table which is presently about 12. m below land surface. Results indicate that 43% of percolation may be through

  8. Dynamic factor modeling of ground and surface water levels in an agricultural area adjacent to Everglades National Park

    Science.gov (United States)

    Ritter, A.; Muñoz-Carpena, R.

    2006-02-01

    The extensive eastern boundary of Everglades National Park (ENP) in south Florida (USA) is subject to one the most expensive and ambitious environmental restoration projects in history. Understanding and predicting the interaction between the shallow aquifer and surface water is a key component for fine-tuning the process. The Frog Pond is an intensively instrumented agricultural 2023 ha area adjacent to ENP. The interactions among 21 multivariate daily time series (ground and surface water elevations, rainfall and evapotranspiration) available from this area were studied by means of dynamic factor analysis, a novel technique in the field of hydrology. This method is designed to determine latent or background effects governing variability or fluctuations in non-stationary time series. Water levels in 16 wells and two drainage ditch locations inside the area were selected as response variables, and canal levels and net recharge as explanatory variables. Elevations in the two canals delimiting the Frog Pond area were found to be the main factors explaining the response variables. This influence of canal elevations on water levels inside the area was complementary and inversely related to the distance between the observation point and each canal. Rainfall events do not affect daily water levels significantly but are responsible for instantaneous or localized groundwater responses that in some cases can be directly associated with the risk of flooding. This close coupling between surface and groundwater levels, that corroborates that found by other authors using different methods, could hinder on-going environmental restoration efforts in the area by bypassing the function of wetlands and other surface features. An empirical model with a reduced set of parameters was successfully developed and validated in the area by interpolating the results from the dynamic factor analysis across the spatial domain (coefficient of efficiency across the domain: 0.66-0.99). Although

  9. Definition of the drainage filter problem

    NARCIS (Netherlands)

    Zaslavsky, D.

    1977-01-01

    It is common to consider the following: I. Retention of soil particles that may enter the drainage pipe and cause its clogging. For some sensitive structures it is important to prevent settlements due to soil transportation by drainage water.

  10. Agriculture: Climate

    Science.gov (United States)

    Climate change affects agricultural producers because agriculture and fisheries depend on specific climate conditions. Temperature changes can cause crop planting dates to shift. Droughts and floods due to climate change may hinder farming practices.

  11. Agricultural Overpopulation

    OpenAIRE

    Bičanić, Rudolf

    2003-01-01

    The author discusses three different approaches to agricultural overpopulation: from the consumption side, from the production side and from the aspect of immobility of agricultural population. In the first approach agrarian overpopulation is defined from the consumption point of viewas the number of people living from agriculture that can live from aggregate agricultural income at a certain standard of consumption. In this connection the problem of measuring total agricultu...

  12. Drainage under increasing and changing requirements

    NARCIS (Netherlands)

    Schultz, E.; Zimmer, D.; Vlotman, W.F.

    2007-01-01

    This year the Working Group on Drainage of the International Commission on Irrigation and Drainage (ICID) celebrates its 25th anniversary. This paper reviews the development of drainage for three different agro-climatic zones, i.e. the temperate (humid), the arid/semi-arid and the humid/semi-humid

  13. Percutaneous catheter drainage of intrapulmonary fluid collection

    International Nuclear Information System (INIS)

    Park, E. D.; Kim, H. J.; Choi, P. Y.; Jung, S. H.

    1994-01-01

    With the success of percutaneous abdominal abscess drainage, attention is now being focused on the use of similar techniques in the thorax. We studied to evaluate the effect of percutaneous drainage in parenchymal fluid collections in the lungs. We performed percutaneous drainage of abscesses and other parenchymal fluid collections of the lungs in 15 patients. All of the procedures were performed under the fluoroscopic guidance with an 18-gauge Seldinger needle and coaxial technique with a 8-10F drainage catheter. Among 10 patients with lung abscess, 8 patients improved by percutaneous catheter drainage. In one patient, drainage was failed by the accidental withdrawal of the catheter before complete drainage. One patient died of sepsis 5 hours after the procedure. Among three patients with complicated bulla, successful drainage was done in two patients, but in the remaining patient, the procedure was failed. In one patient with intrapulmonary bronchogenic cyst, the drainage was not successful due to the thick internal contents. In one patient with traumatic hematoma, after the drainage of old blood clots, the signs of infection disappeared. Overally, of 14 patients excluding one who died, 11 patients improved with percutaneous catheter drainage and three patients did not. There were no major complications during and after the procedure. We conclude that percutaneous catheter drainage is effective and safe procedure for the treatment of parenchymal fluid collections of the lung in patients unresponsive to the medical treatment

  14. Percutaneous catheter drainage of intrapulmonary fluid collection

    Energy Technology Data Exchange (ETDEWEB)

    Park, E. D.; Kim, H. J.; Choi, P. Y.; Jung, S. H. [Gyeongsang National University Hospital, Chinju (Korea, Republic of)

    1994-01-15

    With the success of percutaneous abdominal abscess drainage, attention is now being focused on the use of similar techniques in the thorax. We studied to evaluate the effect of percutaneous drainage in parenchymal fluid collections in the lungs. We performed percutaneous drainage of abscesses and other parenchymal fluid collections of the lungs in 15 patients. All of the procedures were performed under the fluoroscopic guidance with an 18-gauge Seldinger needle and coaxial technique with a 8-10F drainage catheter. Among 10 patients with lung abscess, 8 patients improved by percutaneous catheter drainage. In one patient, drainage was failed by the accidental withdrawal of the catheter before complete drainage. One patient died of sepsis 5 hours after the procedure. Among three patients with complicated bulla, successful drainage was done in two patients, but in the remaining patient, the procedure was failed. In one patient with intrapulmonary bronchogenic cyst, the drainage was not successful due to the thick internal contents. In one patient with traumatic hematoma, after the drainage of old blood clots, the signs of infection disappeared. Overally, of 14 patients excluding one who died, 11 patients improved with percutaneous catheter drainage and three patients did not. There were no major complications during and after the procedure. We conclude that percutaneous catheter drainage is effective and safe procedure for the treatment of parenchymal fluid collections of the lung in patients unresponsive to the medical treatment.

  15. POTENTIALLY TOXIC ELEMENT CYCLES AND CHARACTERIZATION OF MULTIPLE SOURCES IN THE IRRIGATION DITCHES FROM THE RAVENNA COASTAL PLAIN THROUGH TRACE ELEMENTS AND ISOTOPE GEOCHEMISTRY

    Directory of Open Access Journals (Sweden)

    Livia Vittori Antisari

    2010-04-01

    Full Text Available While monitoring the physico-chemical characteristics, trace elements and O-H-Sr-B isotopic data were obtained in superficial waters from a number of irrigations canals and ditches in the Ravenna coastal plain, in order to highlight the cycling of potentially toxic elements and the different sources of the solutes. Surveys were conducted during March and July 2008, and considered as representative of the waters in winter and summer, respectively. In summer, the water mass balance in the network is mostly controlled by the ingression of freshwaters from the Canale Emiliano Romagnolo (CER. The O-H isotopic data indicated that, in winter, waters are primarily recharged from Apennine catchments and undergo evaporation to different extents.The boron isotopic signature indicates the important role played by the marine component. A major seawater contribution was evidenced in canals close to the coastline; however, the process controlling the origin of dissolved boron is not solely related to direct mixing with sea water but comprises an additional source probably related to water-soil exchanges and boron of marine origin leaching, owing to the prolonged exposure of alluvial sediments to sea water. An additional boron contribution from the agricultural practice was is also evidenced. Calculation based on the conservative behaviour of chloride ions indicated that in canals and ditches not directly connected with the sea up to the 80% of the Sr budget did not originate from seawater, indicating a source from Al-silicate minerals and supporting the hypothesis of significant soil-water interactions and chemical exchanges.The positive correlation between pH and dissolved oxygen in winter waters is likely to reflect CO2 consumption during algal photosynthesis, favouring the in-situ generation of colloidal particles due to the oxidative precipitation of ferric iron oxy-hydroxides and probably small carbonate particles able to adsorb trace metals on their

  16. Estimation of Tile Drainage Contribution to Streamflow and Nutrient Export Loads

    Science.gov (United States)

    Schilling, K. E.; Arenas Amado, A.; Jones, C. S.; Weber, L. J.

    2015-12-01

    Subsurface drainage is a very common practice in the agricultural U.S. Midwest. It is typically installed in poorly drained soils in order to enhance crop yields. The presence of tile drains creates a route for agrichemicals to travel and therefore negatively impacts stream water quality. This study estimated through end-member analyses the contributions of tile drainage, groundwater, and surface runoff to streamflow at the watershed scale based on continuously monitored data. Especial attention was devoted to quantifying tile drainage impact on watershed streamflow and nutrient export loads. Data analyzed includes streamflow, rainfall, soil moisture, shallow groundwater levels, in-stream nitrate+nitrite concentrations and specific conductance. Data were collected at a HUC12 watershed located in Northeast Iowa, USA. Approximately 60% of the total watershed area is devoted to agricultural activities and forest and grassland are the other two predominant land uses. Results show that approximately 20% of total annual streamflow comes from tile drainage and during rainfall events tile drainage contribution can go up to 30%. Furthermore, for most of the analyzed rainfall events groundwater responded faster and in a more dramatic fashion than tile drainage. The State of Iowa is currently carrying out a plan to reduce nutrients in Iowa waters and the Gulf of Mexico (Iowa Nutrient Reduction Strategy). The outcome of this investigation has the potential to assist in Best Management Practice (BMP) scenario selection and therefore help the state achieve water quality goals.

  17. Estimates of deep drainage rates at the U.S. Department of Energy Pantex Plant, Amarillo, Texas

    International Nuclear Information System (INIS)

    Fayer, M.J.; Richmond, M.C.; Wigmosta, M.S.; Kelley, M.E.

    1998-04-01

    In FY 1996, the Pacific Northwest National Laboratory (PNNL) provided technical assistance to Battelle Columbus Operations (BCO) in their ongoing assessment of contaminant migration at the Pantex Plant in Amarillo, Texas. The objective of this report is to calculate deep drainage rates at the Pantex Plant. These deep drainage rates may eventually be used to predict contaminant loading to the underlying unconfined aquifer for the Pantex Plant Baseline Risk Assessment. These rates will also be used to support analyses of remedial activities involving surface alterations or the subsurface injection withdrawal of liquids or gases. The scope of this report is to estimate deep drainage rates for the major surface features at the Pantex Plant, including ditches and playas, natural grassland, dryland crop rotation, unvegetated soil, and graveled surfaces. Areas such as Pantex Lake that are outside the main plant boundaries were not included in the analysis. All estimates were derived using existing data or best estimates; no new data were collected. The modeling framework used to estimate the rates is described to enable future correlations, improvements, and enhancements. The scope of this report includes only data gathered during FY 1996. However, a current review of the data gathered on weather, soil, plants, and other information in the time period since did not reveal anything that would significantly alter the results presented in this report

  18. Technical note on drainage systems

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby

    This technical note will present simple but widely used methods for the design of drainage systems. The note will primarily deal with surface water (rainwater) which on a satisfactorily way should be transport into the drainage system. Traditional two types of sewer systems exist: A combined system......, where rainwater and sewage is transported in the same pipe, and a separate system where the two types of water are transported in individual pipe. This note will only focus on the separate rain/stormwater system, however, if domestic sewage should be included in the dimensioning procedure, it......’s not major different than described below - just remember to include this contribution for combined systems where the surface water (rain) and sewage are carried in the same pipes in the system and change some of the parameters for failure allowance (this will be elaborated further later on). The technical...

  19. Biofuel as an Integrated Farm Drainage Management crop: A bioeconomic analysis

    Science.gov (United States)

    Levers, L. R.; Schwabe, K. A.

    2017-04-01

    Irrigated agricultural lands in arid regions often suffer from soil salinization and lack of drainage, which affect environmental quality and productivity. Integrated Farm Drainage Management (IFDM) systems, where drainage water generated from higher-valued crops grown on high quality soils are used to irrigate salt-tolerant crops grown on marginal soils, is one possible strategy for managing salinity and drainage problems. If the IFDM crop were a biofuel crop, both environmental and private benefits may be generated; however, little is known about this possibility. As such, we develop a bioeconomic programming model of irrigated agricultural production to examine the role salt-tolerant biofuel crops might play within an IFDM system. Our results, generated by optimizing profits over land, water, and crop choice decisions subject to resource constraints, suggest that based on the private profits alone, biofuel crops can be a competitive alternative to the common practices of land retirement and nonbiofuel crop production under both low to high drainage water salinity. Yet IFDM biofuel crop production generates 30-35% fewer GHG emissions than the other strategies. The private market competitiveness coupled with the public good benefits may justify policy changes encouraging the growth of IFDM biofuel crops in arid agricultural areas globally.

  20. Anthropogenic modifications to drainage conditions on streamflow variability in the Wabash River basin, Indiana

    Science.gov (United States)

    Chiu, C.; Bowling, L. C.

    2011-12-01

    The Wabash River watershed is the largest watershed in Indiana and includes the longest undammed river reach east of the Mississippi River. The land use of the Wabash River basin began to significantly change from mixed woodland dominated by small lakes and wetlands to agriculture in the mid-1800s and agriculture is now the predominant land use. Over 80% of natural wetland areas were drained to facilitate better crop production through both surface and subsurface drainage applications. Quantifying the change in hydrologic response in this intensively managed landscape requires a hydrologic model that can represent wetlands, crop growth, and impervious area as well as subsurface and surface drainage enhancements, coupled with high resolution soil and topographic inputs. The Variable Infiltration Capacity (VIC) model wetland algorithm has been previously modified to incorporate spatially-varying estimates of water table distribution using a topographic index approach, as well as a simple urban representation. Now, the soil water characteristics curve and a derived drained to equilibrium moisture profile are used to improve the model's estimation of the water table. In order to represent subsurface (tile) drainage, the tile drainage component of subsurface flow is calculated when the simulated water table rises above a specified drain depth. A map of the current estimated extent of subsurface tile drainage for the Wabash River based on a decision tree classifier of soil drainage class, soil slope and agricultural land use is used to activate the new tile drainage feature in the VIC model, while wetland depressional storage capacity is extracted from digital elevation and soil information. This modified VIC model is used to evaluate the performance of model physical variations in the intensively managed hydrologic regime of the Wabash River system and to understand the role of surface and subsurface storage, and land use and land cover change on hydrologic change.

  1. Implications for sustainability of a changing agricultural mosaic in the Sacramento-San Joaquin Delta, California, USA

    Science.gov (United States)

    Lucero, C. E.; Deverel, S. J.; Jacobs, P.; Kelsey, R.

    2015-12-01

    Transformed from the largest wetland system on the west coast of the United States to agriculture, the Sacramento-San Joaquin Delta is an extreme teaching example of anthropogenic threats to sustainability. For over 6,000 years, over 280,000 ha of intertidal freshwater marsh accreted due to seal level rise and sediment deposition. Farming of organic soils since 1850 resulted in land subsidence caused primarily by oxidation. Over 2 billion cubic meters of soil were lost resulting in elevations on Delta islands ranging from -1 to -8 m and increased risk of levee failures and water supply disruption. Alteration of water flows and habitat caused dramatic declines in aquatic species. A cycle in which oxidation of organic soils leads to deepening of drainage ditches to maintain an aerated root zone which in turn results in sustained oxidation and subsidence is perpetuated by the momentum of the status quo despite evidence that agricultural practices are increasingly unsustainable. Flooding of the soils breaks the oxidation/subsidence cycle. We assessed alternate land uses and the carbon market as a potential impetus for change. Using the peer-reviewed and locally calibrated SUBCALC model, we estimated net global warming potential for a range of scenarios for a representative island, from status quo to incorporating significant proportions of subsidence-mitigating land use. We analyzed economic implications by determining profit losses or gains when a simulated GHG offset market is available for wetlands using a regional agricultural production and economic optimization model, We estimated baseline GHG emissions at about 60,000 tons CO2-e per year. In contrast, modeled implementation of rice and wetlands resulted in substantial emissions reductions to the island being a net GHG sink. Subsidence would be arrested or reversed where these land uses are implemented. Results of economic modeling reveal that conversion to wetlands can have significant negative farm financial

  2. Drainage ditches, biodiversity hotspots for aquatic invertebrates : defining and assessing the ecological status of a man-made ecosystem based on macroinvertebrates

    NARCIS (Netherlands)

    Verdonschot, R.C.M.

    2012-01-01

    De effecten van extreme eutrofiëring en organische belasting op de macrofauna in sloten zijn goed bekend. De kennis van de sturende factoren die de samenstelling van de fauna in de ‘standaard poldersloot’ (de eutrofe, vegetatierijke sloot) bepalen, is echter beperkt. In dit proefschrift is

  3. Cultural Resources Survey and Literature Review of Planned Drainage Improvements Along and Adjacent to Ditch 1, Mississippi and Poinsett Counties, Arkansas

    Science.gov (United States)

    1983-01-01

    Archaic, however, that the Hypsithermal period of maximum dryness occurs and it may have been that the ecological effect of this clima - tic trend was...organization of labor and the establishment of widespread complex channels of communication primarily through economic exchange and local redistribution...centralized authorities with the power to draft labor for public works, initiate highly developed means of redistribution that involved, for the first time

  4. Quarterly sampling of the wetlands along the old F-Area effluent ditch: August 1994. Revision 1

    International Nuclear Information System (INIS)

    Cummins, C.L.; Dixon, K.L.

    1994-08-01

    In August 1994, well point water and near-surface water samples were collected to further characterize tritium and volatile organic compounds in the Wetlands along the old F-Area effluent ditch south of 643-E at the Savannah River Plant. Well point samples were collected from seven locations and near-surface water samples were collected at four locations. Results of the August 1994 sampling event further support findings that tritium and volatile organic compounds are outcropping in the Wetlands near the old F-area effluent ditch. Four analytes (1,2-dichloroethylene, trichloroethylene, tritium, and vinyl chloride) were detected at least once at concentrations above the primary Drinking Water Standards or the Maximum Contaminant Levels. Five analytes (the above chemicals plus tetrachloroethylene) were detected at least once in the near-surface water samples at concentrations greater than the method detection limit

  5. Sampling and analysis of soil from the old F-Area effluent ditch and its surrounding wetlands

    International Nuclear Information System (INIS)

    Dixon, K.L.

    1994-06-01

    Four surface soil samples were collected from the wetlands at the old F-Area effluent ditch. All samples were collected near shallow well point locations except FHB012, which was collected from the effluent ditch stream sediment. Samples were analyzed for metals, Target Compound List volatile organic compounds, and gross radiological indicators. Barium, beryllium, and zinc were detected in all four samples and antimony was detected in three of four samples. These metals occur naturally in the wetland soils at the SRS. Comparisons of metals concentrations were male to concentration ranges taken from background wetland soil samples. These comparison, showed that barium and beryllium concentrations were within expected ranges while zinc and antimony concentrations were elevated above expected concentration ranges. Volatile organic compounds were detected in all four samples. Detected compounds included acetone, 2-butanone, chloromethane, cis-1,2-dichloroethene, and toluene. The only radionuclide detected in a significant quantities was tritium which was detected in all four samples

  6. Deep drainage modeling for a fertigated coffee plantation in the brazilian savanna

    NARCIS (Netherlands)

    Pinto, Victor Meriguetti; Reichardt, Klaus; Dam, van Jos; Lier, Quirijn D.J.V.; Bruno, Isabeli Pereira; Durigon, Angelica; Dourado-Neto, Durval; Bortolotto, Rafael Pivotto

    2015-01-01

    Modeling in agriculture represents an important tool to understand processes as water and nutrient losses by drainage, or to test different conditions and scenarios of soil and crop management. Among the existing computational models to describe hydrological processes, SWAP (Soil, Water,

  7. Effectiveness of oat and rye cover crops in reducing nitrate losses in drainage water

    Science.gov (United States)

    A significant portion of the NO3 from agricultural fields that contaminates surface waters in the Midwest Corn Belt is transported to streams or rivers by subsurface drainage systems or “tiles”. Previous research has shown that N fertilizer management alone is not sufficient for reducing NO3 concent...

  8. Peat filtration, field ditches and sedimentation basins for the purification of runoff water from peat mining areas

    International Nuclear Information System (INIS)

    Ihme, R.; Heikkinen, K.; Lakso, E.

    1991-01-01

    The aim of this research is to develop new methods and to improve those already in use to reduce the loading of watercourses from peat excavation areas. Factors examined were the use of peat filtration for the purification of the runoff water, load retention by the means of field ditches and improvement of the practicability and dredging of the settling ponds. Field research was carried out in peat production areas in the province of Oulu in 1987-1989

  9. Restoring coastal wetlands that were ditched for mosquito control: a preliminary assessment of hydro-leveling as a restoration technique

    Science.gov (United States)

    Smith, Thomas J.; Tiling, Ginger; Leasure, Pamela S.

    2007-01-01

    The wetlands surrounding Tampa Bay, Florida were extensively ditched for mosquito control in the 1950s. Spoil from ditch construction was placed adjacent to the wetlands ditches creating mound-like features (spoil-mounds). These mounds represent a loss of 14% of the wetland area in Tampa Bay. Spoil mounds interfere with tidal flow and are locations for non-native plants to colonize (e.g., Schinus terebinthifolius). Removal of the spoil mounds to eliminate exotic plants, restore native vegetation, and re-establish natural hydrology is a restoration priority for environmental managers. Hydro-leveling, a new technique, was tested in a mangrove forest restoration project in 2004. Hydro-leveling uses a high pressure stream of water to wash sediment from the spoil mound into the adjacent wetland and ditch. To assess the effectiveness of this technique, we conducted vegetation surveys in areas that were hydro-leveled and in non-hydro-leveled areas 3 years post-project. Adult Schinus were reduced but not eliminated from hydro-leveled mounds. Schinus seedlings however were absent from hydro-leveled sites. Colonization by native species was sparse. Mangrove seedlings were essentially absent (≈2 m−2) from the centers of hydro-leveled mounds and were in low density on their edges (17 m−2) in comparison to surrounding mangrove forests (105 m−2). Hydro-leveling resulted in mortality of mangroves adjacent to the mounds being leveled. This was probably caused by burial of pneumatophores during the hydro-leveling process. For hydro-leveling to be a useful and successful restoration technique several requirements must be met. Spoil mounds must be lowered to the level of the surrounding wetlands. Spoil must be distributed further into the adjacent wetland to prevent burial of nearby native vegetation. Finally, native species may need to be planted on hydro-leveled areas to speed up the re-vegetation process.

  10. Mine Drainage Generation and Control Options.

    Science.gov (United States)

    Wei, Xinchao; Rodak, Carolyn M; Zhang, Shicheng; Han, Yuexin; Wolfe, F Andrew

    2016-10-01

    This review provides a snapshot of papers published in 2015 relevant to the topic of mine drainage generation and control options. The review is broken into 3 sections: Generation, Prediction and Prevention, and Treatment Options. The first section, mine drainage generation, focuses on the characterization of mine drainage and the environmental impacts. As such, it is broken into three subsections focused on microbiological characterization, physiochemical characterization, and environmental impacts. The second section of the review is divided into two subsections focused on either the prediction or prevention of acid mine drainage. The final section focuses on treatment options for mine drainage and waste sludge. The third section contains subsections on passive treatment, biological treatment, physiochemical treatment, and a new subsection on beneficial uses for mine drainage and treatment wastes.

  11. An economic case for drainage for sustainable irrigation: Case studies in the lower Vaal and Riet catchments

    OpenAIRE

    RJ Armour; MF Viljoen

    2014-01-01

    Where evaporation exceeds precipitation salinisation is inevitable. This paper presents a multidisciplinary framework of the dynamic interactions between the hydrology, bio-physical and economics of irrigated agriculture in a semi arid area. Status quo drainage and cropping situations are compared to a scenario of increased drainage and leaching and subsequent higher value crops. Stochastically generated hydrology data fitted to a salinisation:yield production function is inputted in a crop e...

  12. Effects of lambda-cyhalothrin in two ditch microcosm systems of different trophic status.

    Science.gov (United States)

    Roessink, Ivo; Arts, Gertie H P; Belgers, J Dick M; Bransen, Fred; Maund, Steve J; Brock, Theo C M

    2005-07-01

    The fate and effects of the pyrethroid insecticide lambda-cyhalothrin were compared in mesotrophic (macrophyte-dominated) and eutrophic (phytoplankton-dominated) ditch microcosms (approximately 0.5 m3). Lambda-cyhalothrin was applied three times at one-week intervals at concentrations of 10, 25, 50, 100, and 250 ng/L. The rate of dissipation of lambda-cyhalothrin in the water column of the two types of test systems was similar. After 1 d, only 30% of the amount applied remained in the water phase. Initial, direct effects were observed primarily on arthropod taxa. The most sensitive species was the phantom midge (Chaoborus obscuripes). Threshold levels for slight and transient direct toxic effects were similar (10 ng/L) between types of test systems. At treatment levels of 25 ng/L and higher, apparent population and community responses occurred. At treatments of 100 and 250 ng/L, the rate of recovery of the macroinvertebrate community was lower in the macrophyte-dominated systems, primarily because of a prolonged decline of the amphipod Gammarus pulex. This species occurred at high densities only in the macrophyte-dominated enclosures. Indirect effects (e.g., increase of rotifers and microcrustaceans) were more pronounced in the plankton-dominated test systems, particularly at treatment levels of 25 ng/L and higher.

  13. [Endoscopic ultrasound guided rendezvous for biliary drainage].

    Science.gov (United States)

    Knudsen, Marie Høxbro; Vilmann, Peter; Hassan, Hazem; Karstensen, John Gésdal

    2015-04-27

    Endoscopic retrograde cholangiography (ERCP) is currently standard treatment for biliary drainage. Endoscopic ultrasound guided rendezvous (EUS-RV) is a novel method to overcome an unsuccessful biliary drainage procedure. Under endoscopic ultrasound guidance a guidewire is passed via a needle from the stomach or duodenum to the common bile duct and from there on to the duodenum enabling ERCP. With a relatively high rate of success EUS-RV should be considered as an alternative to biliary drainage and surgical intervention.

  14. Percutaneous drainage treatment of primary liver abscesses

    Energy Technology Data Exchange (ETDEWEB)

    Berger, H.; Pratschke, E.; Berr, F.; Fink, U.

    1989-02-01

    28 primary liver abscesses, including 9 amoebic abscesses, in 24 patients were drained percutaneously. Indication for drainage in amoebic abscesses was imminent rupture and clinical symptoms as pleural effusion, lung atelectasis and pain. 95% of the primary abscesses were cured by percutaneous drainage and systemic antibiotic treatment. There was one recurrence of abscess, which was managed surgically. Reasons for drainage failure were: tumour necrosis and tumour perforation with secondary liver abscess.

  15. Percutaneous drainage treatment of primary liver abscesses

    International Nuclear Information System (INIS)

    Berger, H.; Pratschke, E.; Berr, F.; Fink, U.; Klinikum Grosshadern, Muenchen; Klinikum Grosshadern, Muenchen

    1989-01-01

    28 primary liver abscesses, including 9 amoebic abscesses, in 24 patients were drained percutaneously. Indication for drainage in amoebic abscesses was imminent rupture and clinical symptoms as pleural effusion, lung atelectasis and pain. 95% of the primary abscesses were cured by percutaneous drainage and systemic antibiotic treatment. There was one recurrence of abscess, which was managed surgically. Reasons for drainage failure were: tumour necrosis and tumour perforation with secondary liver abscess. (orig.) [de

  16. Percutaneous catheter drainage of lung abscess

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Shin; Chun, Kyung Ah; Choi, Hyo Sun; Ha, Hyun Kown; Shinn, Kyung Sub [Catholic University Medical college, Seoul (Korea, Republic of)

    1993-09-15

    From March 1987 to July 1989, six patients (five adults and one child) with lung abscess (size, 5-13 cm in diameter) were treated with percutaneous aspiration and drainage. In each case, the puncture was made where the wall of the abscess was in contact with the pleural surface. An 8 to 10 Fr cartheter was inserted for drainage. Five of 6 had a dynamatic clinical response within 24 hours of the drainage. Percutaneous drainage was successful with complete abscess resolution in four and partial resolution in one patient. No response was seen in the rest one. The duration of drainage ranged from 7 to 18 days(average, 15.5 days) in successful cases. One case of the failure in drainage was due tio persistent aspiration of the neurologically impaired patient. In one patient, the abscess resolved after drainage but recurred after inadvertent removal of the catheter 7 days after insertion. In two patients, concurrent pleural empyema was resolved completely by the drainage. Computed tomography provide anatomic details necessary for choosing the puncture site and avoiding a puncture of the lung parenchyma. Percutaneous catheter drainage is safe and effective method for treating patient with lung abscess.

  17. Percutaneous catheter drainage of lung abscess

    International Nuclear Information System (INIS)

    Kim, Young Shin; Chun, Kyung Ah; Choi, Hyo Sun; Ha, Hyun Kown; Shinn, Kyung Sub

    1993-01-01

    From March 1987 to July 1989, six patients (five adults and one child) with lung abscess (size, 5-13 cm in diameter) were treated with percutaneous aspiration and drainage. In each case, the puncture was made where the wall of the abscess was in contact with the pleural surface. An 8 to 10 Fr cartheter was inserted for drainage. Five of 6 had a dynamatic clinical response within 24 hours of the drainage. Percutaneous drainage was successful with complete abscess resolution in four and partial resolution in one patient. No response was seen in the rest one. The duration of drainage ranged from 7 to 18 days(average, 15.5 days) in successful cases. One case of the failure in drainage was due tio persistent aspiration of the neurologically impaired patient. In one patient, the abscess resolved after drainage but recurred after inadvertent removal of the catheter 7 days after insertion. In two patients, concurrent pleural empyema was resolved completely by the drainage. Computed tomography provide anatomic details necessary for choosing the puncture site and avoiding a puncture of the lung parenchyma. Percutaneous catheter drainage is safe and effective method for treating patient with lung abscess

  18. Composite fibrous glaucoma drainage implant

    Science.gov (United States)

    Klapstova, A.; Horakova, J.; Shynkarenko, A.; Lukas, D.

    2017-10-01

    Glaucoma is a frequent reason of loss vision. It is usually caused by increased intraocular pressure leading to damage of optic nerve head. This work deals with the development of fibrous structure suitable for glaucoma drainage implants (GDI). Commercially produced metallic glaucoma implants are very effective in lowering intraocular pressure. However, these implants may cause adverse events such as damage to adjacent tissue, fibrosis, hypotony or many others [1]. The aim of this study is to reduce undesirable properties of currently produced drains and improve their properties by creating of the composite fibrous drain for achieve a normal intraocular pressure. Two types of electrospinning technologies were used for the production of very small tubular implants. First type was focused for production of outer part of tubular drain and the second type of electrospinning method made the inner part of shape follows the connections of both parts. Complete implant had a special properties suitable for drainage of fluid. Morphological parameters, liquid transport tests and in-vitro cell adhesion tests were detected.

  19. Estimating drain flow from measured water table depth in layered soils under free and controlled drainage

    Science.gov (United States)

    Saadat, Samaneh; Bowling, Laura; Frankenberger, Jane; Kladivko, Eileen

    2018-01-01

    Long records of continuous drain flow are important for quantifying annual and seasonal changes in the subsurface drainage flow from drained agricultural land. Missing data due to equipment malfunction and other challenges have limited conclusions that can be made about annual flow and thus nutrient loads from field studies, including assessments of the effect of controlled drainage. Water table depth data may be available during gaps in flow data, providing a basis for filling missing drain flow data; therefore, the overall goal of this study was to examine the potential to estimate drain flow using water table observations. The objectives were to evaluate how the shape of the relationship between drain flow and water table height above drain varies depending on the soil hydraulic conductivity profile, to quantify how well the Hooghoudt equation represented the water table-drain flow relationship in five years of measured data at the Davis Purdue Agricultural Center (DPAC), and to determine the impact of controlled drainage on drain flow using the filled dataset. The shape of the drain flow-water table height relationship was found to depend on the selected hydraulic conductivity profile. Estimated drain flow using the Hooghoudt equation with measured water table height for both free draining and controlled periods compared well to observed flow with Nash-Sutcliffe Efficiency values above 0.7 and 0.8 for calibration and validation periods, respectively. Using this method, together with linear regression for the remaining gaps, a long-term drain flow record for a controlled drainage experiment at the DPAC was used to evaluate the impacts of controlled drainage on drain flow. In the controlled drainage sites, annual flow was 14-49% lower than free drainage.

  20. Reducing nitrate loss in tile drainage water with cover crops and water-table management systems.

    Science.gov (United States)

    Drury, C F; Tan, C S; Welacky, T W; Reynolds, W D; Zhang, T Q; Oloya, T O; McLaughlin, N B; Gaynor, J D

    2014-03-01

    Nitrate lost from agricultural soils is an economic cost to producers, an environmental concern when it enters rivers and lakes, and a health risk when it enters wells and aquifers used for drinking water. Planting a winter wheat cover crop (CC) and/or use of controlled tile drainage-subirrigation (CDS) may reduce losses of nitrate (NO) relative to no cover crop (NCC) and/or traditional unrestricted tile drainage (UTD). A 6-yr (1999-2005) corn-soybean study was conducted to determine the effectiveness of CC+CDS, CC+UTD, NCC+CDS, and NCC+UTD treatments for reducing NO loss. Flow volume and NO concentration in surface runoff and tile drainage were measured continuously, and CC reduced the 5-yr flow-weighted mean (FWM) NO concentration in tile drainage water by 21 to 38% and cumulative NO loss by 14 to 16% relative to NCC. Controlled tile drainage-subirrigation reduced FWM NO concentration by 15 to 33% and cumulative NO loss by 38 to 39% relative to UTD. When CC and CDS were combined, 5-yr cumulative FWM NO concentrations and loss in tile drainage were decreased by 47% (from 9.45 to 4.99 mg N L and from 102 to 53.6 kg N ha) relative to NCC+UTD. The reductions in runoff and concomitant increases in tile drainage under CC occurred primarily because of increases in near-surface soil hydraulic conductivity. Cover crops increased corn grain yields by 4 to 7% in 2004 increased 3-yr average soybean yields by 8 to 15%, whereas CDS did not affect corn or soybean yields over the 6 yr. The combined use of a cover crop and water-table management system was highly effective for reducing NO loss from cool, humid agricultural soils. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  1. Subsurface drainage volume reduction with drainage water management: Case studies in Ohio, USA

    Science.gov (United States)

    One of the main contributors to poor water quality in the Mississippi River and aeral increase in the hypoxic zone in the Gulf of Mexico is intensive drainage of the cropland within the watershed. Controlled drainage has been demonstrated as an approach to curb totla drainage outflow and nutrient di...

  2. Comprehensive nitrogen budgets for controlled tile drainage fields in eastern ontario, Canada.

    Science.gov (United States)

    Sunohara, M D; Craiovan, E; Topp, E; Gottschall, N; Drury, C F; Lapen, D R

    2014-03-01

    Excessive N loading from subsurface tile drainage has been linked to water quality degradation. Controlled tile drainage (CTD) has the potential to reduce N losses via tile drainage and boost crop yields. While CTD can reduce N loss from tile drainage, it may increase losses through other pathways. A multiple-year field-scale accounting of major N inputs and outputs during the cropping season was conducted on freely drained and controlled tile drained agricultural fields under corn ( L.)-soybean [ (L.) Merr.] production systems in eastern Ontario, Canada. Greater predicted gaseous N emissions for corn and soybean and greater observed lateral seepage N losses were observed for corn and soybean fields under CTD relative to free-draining fields. However, observed N losses from tile were significantly lower for CTD fields, in relation to freely drained fields. Changes in residual soil N were essentially equivalent between drainage treatments, while mass balance residual terms were systematically negative (slightly more so for CTD). Increases in plant N uptake associated with CTD were observed, probably resulting in higher grain yields for corn and soybean. This study illustrates the benefits of CTD in decreasing subsurface tile drainage N losses and boosting crop yields, while demonstrating the potential for CTD to increase N losses via other pathways related to gaseous emissions and groundwater seepage. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  3. Agriculture Sectors

    Science.gov (United States)

    The Agriculture sectors comprise establishments primarily engaged in growing crops, raising animals, and harvesting fish and other animals. Find information on compliance, enforcement and guidance on EPA laws and regulations on the NAICS 111 & 112 sectors.

  4. Dynamic drainage of froth with wood fibers

    Science.gov (United States)

    J.Y. Zhu; Freya Tan

    2005-01-01

    Understanding froth drainage with fibers (or simply called fiber drainage in froth) is important for improving fiber yield in the flotation deinking operation. In this study, the data of water and fiber mass in foams collected at different froth heights were used to reconstruct the time dependent and spatially resolved froth density and fiber volumetric concentration...

  5. Tile drainage phosphorus loss with long-term consistent cropping systems and fertilization.

    Science.gov (United States)

    Zhang, T Q; Tan, C S; Zheng, Z M; Drury, C F

    2015-03-01

    Phosphorus (P) loss in tile drainage water may vary with agricultural practices, and the impacts are often hard to detect with short-term studies. We evaluated the effects of long-term (≥43 yr) cropping systems (continuous corn [CC], corn-oats-alfalfa-alfalfa rotation [CR], and continuous grass [CS]) and fertilization (fertilization [F] vs. no-fertilization [NF]) on P loss in tile drainage water from a clay loam soil over a 4-yr period. Compared with NF, long-term fertilization increased concentrations and losses of dissolved reactive P (DRP), dissolved unreactive P (DURP), and total P (TP) in tile drainage water, with the increments following the order: CS > CR > CC. Dissolved P (dissolved reactive P [DRP] and dissolved unreactive P [DURP]) was the dominant P form in drainage outflow, accounting for 72% of TP loss under F-CS, whereas particulate P (PP) was the major form of TP loss under F-CC (72%), F-CR (62%), NF-CS (66%), NF-CC (74%), and NF-CR (72%). Dissolved unreactive P played nearly equal roles as DRP in P losses in tile drainage water. Stepwise regression analysis showed that the concentration of P (DRP, DURP, and PP) in tile drainage flow, rather than event flow volume, was the most important factor contributing to P loss in tile drainage water, although event flow volume was more important in PP loss than in dissolved P loss. Continuous grass significantly increased P loss by increasing P concentration and flow volume of tile drainage water, especially under the fertilization treatment. Long-term grasslands may become a significant P source in tile-drained systems when they receive regular P addition. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  6. Agriculture: About EPA's National Agriculture Center

    Science.gov (United States)

    EPA's National Agriculture Center (Ag Center), with the support of the United States Department of Agriculture, serves growers, livestock producers, other agribusinesses, and agricultural information/education providers.

  7. Journal of Agriculture and Social Research (JASR) Vol. 16, No. 2 ...

    African Journals Online (AJOL)

    DR Amadi

    The study revealed that agricultural mechanization can be used to carry out different ... reduce drudgery, ensure food sufficiency, encourage foreign exchange ... stressed that fragmentation of land with numerous canals, drainages and narrow ...

  8. Percutaneous catheter drainage of tuberculous psoas abscesses

    International Nuclear Information System (INIS)

    Pombo, F.; Martin-Egana, R.; Cela, A.; Diaz, J.L.; Linares-Mondejar, P.; Freire, M.

    1993-01-01

    Six patients with 7 tuberculous psoas or ilio-psoas abscesses were treated by CT-guided catheter drainage and chemotherapy. The abscesses (5 unilateral and 1 bilateral) were completely drained using a posterior or lateral approach. The abscess volume was 70 to 700 ml (mean 300 ml) and the duration of drainage 5 to 11 days (mean 7 days). Immediate local symptomatic improvement was achieved in all patients, and there were no procedural complications. CT follow-up at 3 to 9 months showed normalization in 5 patients, 2 of whom are still in medical therapy. One patient, who did not take the medication regularly, had a recurrent abscess requiring new catheter drainage after which the fluid collection disappeared. Percutaneous drainage represents an efficient and attractive alternative to surgical drainage as a supplement to medical therapy in the management of patients with large tuberculous psoas abscesses. (orig.)

  9. Decommissioning of a RCRA Treatment, Storage, and Disposal Facility: A case study of the 216-A-29 ditch at the Hanford Site

    International Nuclear Information System (INIS)

    Smith, D.L.; Hayward, W.M.

    1991-09-01

    The 216-A-29 ditch is located in the central portion of the Hanford Site with Operable Unit 200-PO-5. The ditch is classified under the Resource Conservation and Recovery Act of 1976 as a Treatment, Storage, and Disposal (TSD) Facility and as such, is to be removed from service in support of the Hanford Federal Facility Agreement and Consent Order Tri-Party Agreement (Ecology et al. 1989) Milestone M-17-10, which states ''cease all liquid discharges to hazardous land disposal units unless such units have been clean closed in accordance with the Resource Conservation and Recovery Act of 1976''. The 216-A-29 ditch is one stream feeding the 216-B-3 Pond system, and its removal from service was necessary to support the closure strategy for the 216-B-3 Pond system. Interim stabilization of the 216-A-29 ditch is the first step required to comply with the Tri-Party Agreement (Ecology et al. 1989) and the eventual decommissioning of the entire B Pond system. Interim stabilization was required to maintain the 216-A-29 ditch in a stable configuration until closure actions have been determined and initiated. 4 refs., 3 figs

  10. Abdominal drainage versus no drainage post gastrectomy for gastric cancer.

    Science.gov (United States)

    Wang, Zhen; Chen, Junqiang; Su, Ka; Dong, Zhiyong

    2011-08-10

    Gastrectomy remains the primary therapeutic method for resectable gastric cancer. Thought of as an important measure to reduce post-operative complications and mortality, abdominal drainage was used widely after gastrectomy for gastric cancer in previous decades. The benefits of abdominal drainage have been questioned by researchers in recent years. The objectives of this review were to access the benefits and harms of routine abdominal drainage post gastrectomy for gastric cancer. We searched the Cochrane Controlled Trials Register (Central/CCTR) in The Cochrane Library (2010, Issue 10), including the Specialised Registers of the Cochrane Upper Gastrointestinal and Pancreatic Diseases (UGPD) Group; MEDLINE (via Pubmed, 1950 to October, 2010); EMBASE (1980 to October, 2010); and the Chinese National Knowledge Infrastructure (CNKI) Database (1979 to October, 2010). We included randomised controlled trials (RCTs) comparing abdominal drain versus no drain in patients who had undergone gastrectomy (not considering the scale of gastrectomy and the extent of lymphadenectomy; irrespective of language, publication status, and the type of drain). We excluded RCTs comparing one drain with another. From each trial, we extracted the data on the methodological quality and characteristics of the included studies, mortality (30-day mortality), re-operations, post-operative complications (pneumonia, wound infection, intra-abdominal abscess, anastomotic leak, drain-related complications), operation time, length of post-operative hospital stay and initiation of soft diet. For dichotomous data, we calculated the risk ratio (RR) and 95% confidence intervals (CI). For continuous data, we calculated mean differences (MD) and 95% CI. We tested heterogeneity using the Chi(2) test. We used a fixed-effect model for data analysis with RevMan software but we used a random-effects model if the P value of the Chi(2) test was less than 0.1. We included four RCTs involving 438 patients (220

  11. Geohydrologic reconnaissance of drainage wells in Florida

    Science.gov (United States)

    Kimrey, J.O.; Fayard, L.D.

    1984-01-01

    Drainage wells are used to inject surface waters directly into an aquifer, or shallow ground waters directly into a deeper aquifer, primarily by gravity. Such wells in Florida may be grouped into two broad types: (1) surface-water injection wells, and (2) interaquifer connector wells. Drainage wells of the first type are further categorized as either Floridan aquifer drainage wells or Biscayne aquifer drainage wells. Floridan aquifer drainage wells are commonly used to supplement drainage for urban areas in karst terranes of central and north Florida. Data are available for 25 wells in the Ocala, Live Oak, and Orlando areas that allow comparison of the quality of water samples from these Floridan aquifer drainage wells with allowable contaminant levels. Comparison indicates that maximum contaminant levels for turbidity, color, and iron, manganese, and lead concentrations are equaled or exceeded in some drainage-well samples, and relatively high counts for coliform bacteria are present in most wells. Biscayne aquifer drainage wells are used locally to dispose of stormwater runoff and other surplus water in southeast Florida, where large numbers of these wells have been permitted in Dade and Broward Counties. The majority of these wells are used to dispose of water from swimming pools or to dispose of heated water from air-conditioning units. The use of Biscayne aquifer drainage wells may have minimal effect on aquifer potability so long as injection of runoff and industrial wates is restricted to zones where chloride concentrations exceed 1,500 milligrams per liter. Interaquifer connector wells are used in the phosphate mining areas of Polk and Hillsborough Counties, to drain mines and recharge the Floridan aquifer. Water-quality data available from 13 connector wells indicate that samples from most of these wells exceed standards values for iron concentration and turbidity. One well yielded a highly mineralized water, and samples from 6 of the other 12 wells exceed

  12. Borehole data package for the 216-S-10 pond and ditch well 299-W26-13

    International Nuclear Information System (INIS)

    Horton, D.G.; Williams, B.A.; Cearlock, C.S.

    2000-01-01

    One new Resource Conservation and Recovery Act (RCRA) groundwater monitoring well was installed at the 216-S-10 pond and ditch during November and December 1999 in fulfillment of Tri-Party Agreement (Ecology 1996) milestone M-24-42. The well is 299-W26-13 and is located at the northeast comer to the 216-S-10 pond, southwest of 200 West Area. The well is a new downgradient well in the monitoring network. A figure shows the locations of all wells in the 216-S-10 pond and ditch monitoring network. The new well was constructed to the specifications and requirements described in Washington Administrative Code (WAC) 173-160 and WAC 173-303, the groundwater monitoring plan for the 216-S-10 pond and ditch (Airhart et al. 1990), and the description of work for well drilling and installation. During drilling and construction of well 299-W26-13, sampling and analysis activities were done to support remedial action, closure decisions at treatment, storage and disposal facilities, and to confirm preliminary site conceptual models developed in the 200-CS-1 Work Plan (DOE/RL 1999). This document compiles information on the drilling and construction, well development, pump installation, and sediment and groundwater testing applicable to well 299-W26-13. Appendix A contains the Well Summary Sheet (as-built diagram), the Well Construction Summary Report, and the geologist's log. Appendix B contains results of field and laboratory determinations of physical and chemical properties of sediment samples. Appendix C contains borehole geophysical logs. Additional documentation concerning well construction is on file with Bechtel Hanford, Inc., Richland, Washington

  13. Growth characteristics and nutrient removal capability of eco-ditch plants in mesocosm sediment receiving primary domestic wastewater.

    Science.gov (United States)

    Kumwimba, Mathieu Nsenga; Zhu, Bo; Muyembe, Diana Kavidia; Dzakpasu, Mawuli

    2017-10-01

    Eco-ditches are being explored to maximize their capability of capturing pollutants and mitigate any harmful side effects in rivers. In this study, mesocosm plastic drum sediment and field experiments were set up to screen 18 plant species found in ditches and identify those with potential for high biomass production and nutrients removal. Terrestrial plants grown in the mesocosm system were shown to be able to acclimate to aquatic conditions and to survive in primary domestic sewage. About 73-95% increase in plant biomass was recorded. Removal efficiencies for total nitrogen, total phosphorus, and ammonium-nitrogen from the sewage of 72-99%, 64-99%, and 75-100%, respectively, were recorded. Furthermore, complete removal of the applied nitrate-nitrogen load was achieved in mesocosm systems. Findings also show that all species, but especially Acorus calamus, Canna indica, Canna lily, Cyperus alternifolius, Colocasia gigantea, Eichhornia crassipes, Iris sibirica, and Typha latifolia had the highest efficiencies for nitrogen and phosphorous removal. The N and P mass balance analysis demonstrated that plant uptake and sediment N and P accumulation accounted for 41-86% and 18-49% of the total influent TN and TP loads, respectively. In addition, the amounts of nitrogen and phosphorous uptake by these plant species were influenced significantly by biomass. The field-culture experiment further identified Canna indica followed by Cyperus alternifolius as the most promising for high biomass production and nutrients uptake. Therefore, these plants may be recommended for extensive use in treating highly eutrophicated rivers. Outcomes of this work can be useful for model design specifications in eco-ditch mitigation of sewage pollution.

  14. Radiologically-guided catheter drainage of intrathoracic abscesses and empyemas

    International Nuclear Information System (INIS)

    Berger, H.; Steiner, W.; Bergman, C.; Anthuber, M.; Dienemann, H.

    1993-01-01

    Radiologically guided percutaneous catheter drainage was used in 38 patients to treat pleural empyemas (35 patients) and pulmonary abscesses (3 patients). Drainage was successful in 85.7% of empyemas including 11 cases with fistulous communications. Three percutaneously drained pulmonary abscesses required subsequent lobectomy. One patient died during the drainage procedure due to sepsis. No major complications related to the drainage procedure were observed. Guided percutaneous drainage proved to be a safe and successful alternative to closed drainage of pleural fluid collections. (orig.)

  15. Agriculture applications

    International Nuclear Information System (INIS)

    Bastidas O, G.; Obando D, R.; Alvarez F, A.

    1989-01-01

    Since its beginnings, the Agricultural Area had a selected research team involved in the development of different agricultural techniques. Currently, there are two main branches engaged in the solution of agricultural problems: Soil fertility and induced mutations. Soil fertility: Within this branch, studies on soil nutrients and availability of water and light resources, have been made by using isotope methods. In the near future studies on nitrogen and potassium content in potato, rice and wheat plantations will be held. Induced mutations: The main objective of this team is to obtain through radioinduced mutations, as well as in vitro growth, improved rice and other cereal seeds to be used under hostile environmental conditions. The further goal will be to develop new genotypes straight from the mutants or by utilization of this material as breeding materials in interchange programs

  16. Impacts of Watershed Characteristics and Crop Rotations on Winter Cover Crop Nitrate-Nitrogen Uptake Capacity within Agricultural Watersheds in the Chesapeake Bay Region.

    Science.gov (United States)

    Lee, Sangchul; Yeo, In-Young; Sadeghi, Ali M; McCarty, Gregory W; Hively, W Dean; Lang, Megan W

    2016-01-01

    The adoption rate of winter cover crops (WCCs) as an effective conservation management practice to help reduce agricultural nutrient loads in the Chesapeake Bay (CB) is increasing. However, the WCC potential for water quality improvement has not been fully realized at the watershed scale. This study was conducted to evaluate the long-term impact of WCCs on hydrology and NO3-N loads in two adjacent watersheds and to identify key management factors that affect the effectiveness of WCCs using the Soil and Water Assessment Tool (SWAT) and statistical methods. Simulation results indicated that WCCs are effective for reducing NO3-N loads and their performance varied based on planting date, species, soil characteristics, and crop rotations. Early-planted WCCs outperformed late-planted WCCs on the reduction of NO3-N loads and early-planted rye (RE) reduced NO3-N loads by ~49.3% compared to the baseline (no WCC). The WCCs were more effective in a watershed dominated by well-drained soils with increased reductions in NO3-N fluxes of ~2.5 kg N·ha-1 delivered to streams and ~10.1 kg N·ha-1 leached into groundwater compared to poorly-drained soils. Well-drained agricultural lands had higher transport of NO3-N in the soil profile and groundwater due to increased N leaching. Poorly-drained agricultural lands had lower NO3-N due to extensive drainage ditches and anaerobic soil conditions promoting denitrification. The performance of WCCs varied by crop rotations (i.e., continuous corn and corn-soybean), with increased N uptake following soybean crops due to the increased soil mineral N availability by mineralization of soybean residue compared to corn residue. The WCCs can reduce N leaching where baseline NO3-N loads are high in well-drained soils and/or when residual and mineralized N availability is high due to the cropping practices. The findings suggested that WCC implementation plans should be established in watersheds according to local edaphic and agronomic

  17. Impacts of Watershed Characteristics and Crop Rotations on Winter Cover Crop Nitrate-Nitrogen Uptake Capacity within Agricultural Watersheds in the Chesapeake Bay Region.

    Directory of Open Access Journals (Sweden)

    Sangchul Lee

    Full Text Available The adoption rate of winter cover crops (WCCs as an effective conservation management practice to help reduce agricultural nutrient loads in the Chesapeake Bay (CB is increasing. However, the WCC potential for water quality improvement has not been fully realized at the watershed scale. This study was conducted to evaluate the long-term impact of WCCs on hydrology and NO3-N loads in two adjacent watersheds and to identify key management factors that affect the effectiveness of WCCs using the Soil and Water Assessment Tool (SWAT and statistical methods. Simulation results indicated that WCCs are effective for reducing NO3-N loads and their performance varied based on planting date, species, soil characteristics, and crop rotations. Early-planted WCCs outperformed late-planted WCCs on the reduction of NO3-N loads and early-planted rye (RE reduced NO3-N loads by ~49.3% compared to the baseline (no WCC. The WCCs were more effective in a watershed dominated by well-drained soils with increased reductions in NO3-N fluxes of ~2.5 kg N·ha-1 delivered to streams and ~10.1 kg N·ha-1 leached into groundwater compared to poorly-drained soils. Well-drained agricultural lands had higher transport of NO3-N in the soil profile and groundwater due to increased N leaching. Poorly-drained agricultural lands had lower NO3-N due to extensive drainage ditches and anaerobic soil conditions promoting denitrification. The performance of WCCs varied by crop rotations (i.e., continuous corn and corn-soybean, with increased N uptake following soybean crops due to the increased soil mineral N availability by mineralization of soybean residue compared to corn residue. The WCCs can reduce N leaching where baseline NO3-N loads are high in well-drained soils and/or when residual and mineralized N availability is high due to the cropping practices. The findings suggested that WCC implementation plans should be established in watersheds according to local edaphic and agronomic

  18. Percutaneous biliary drainage and stenting

    International Nuclear Information System (INIS)

    Totev, M.

    2012-01-01

    Full text: Percutaneous transhepatic cholangiography (PTC) is an X-ray or US guided procedure that involves the injection of a contrast material directly into the bile ducts inside the liver to produce pictures of them. If a blockage or narrowing is found, additional procedures may be performed: 1. insertion of a catheter to drain excess bile out of the body or both - internal and external; 2. plastic endoprothesis placement; 3. self-expandable metal stents placement to help open bile ducts or to bypass an obstruction and allow fluids to drain. Current percutaneous biliary interventions include percutaneous transhepatic cholangiography (PTC) and biliary drainage to manage benign and malignant obstructions. Internal biliary stents are either plastic or metallic, and various types of each kind are available. Internal biliary stents have several advantages. An external tube can be uncomfortable and have a psychological disadvantage. An internal stent prevents the problems related to external catheters, for example, pericatheter leakage of bile and the need for daily flushing. The disadvantages include having to perform endoscopic retrograde cholangiopancreatography (ERCP) or new PTC procedures to obtain access in case of stent obstruction. Better patency rates are reported with metallic than with plastic stents in cases of malignant obstruction, though no effect on survival is noted. Plastic internal stents are the cheapest but reportedly prone to migration. Metallic stents are generally not used in the treatment of benign disease because studies have shown poor long-term patency rates. Limited applications may include the treatment of patients who are poor surgical candidates or of those in whom surgical treatment fails. Most postoperative strictures are treated surgically, though endoscopic and (less commonly) percutaneous placement of nonmetallic stents has increasingly been used in the past few years. Now there are some reports about use of biodegradable biliary

  19. Agricultural sector

    International Nuclear Information System (INIS)

    Ainul Hayati Daud; Hazmimi Kasim

    2010-01-01

    The applications of nuclear technology in agriculture sector cover the use of the technology at every aspects of agricultural activity, starting from the seed to harvesting as well as the management of plantations itself. In this sector, a total of 55 entities comprising 17 public agencies and 38 private companies were selected for the study. Almost all, 91 % of them are located in Peninsular Malaysia; the rest operates in Sabah and Sarawak. The findings of the study in the public agencies and private companies are presented in the next sections. (author)

  20. Agricultural methanization

    International Nuclear Information System (INIS)

    2011-01-01

    After having briefly outlined the interest of the development of methanization of agricultural by-products in the context of struggle against climate change, and noticed that France is only now developing this sector as some other countries already did, this publication describes the methanization process also called anaerobic digestion, which produces a digestate and biogas. Advantages for the agriculture sector are outlined, as well as drawbacks and recommendations (required specific technical abilities, an attention to the use of energetic crops, an improved economic balance which still depends on public subsidies, competition in the field of waste processing). Actions undertaken by the ADEME are briefly evoked

  1. Postoperative drainage in head and neck surgery.

    Science.gov (United States)

    Amir, Ida; Morar, Pradeep; Belloso, Antonio

    2010-11-01

    A major factor affecting patients' length of hospitalisation following head and neck surgery remains the use of surgical drains. The optimal time to remove these drains has not been well defined. A routine practice is to measure the drainage every 24 h and remove the drain when daily drainage falls below 25 ml. This study aims to determine whether drainage measurement at shorter intervals decreases the time to drain removal and hence the length of in-patient stays. A 6-month prospective observational study was performed. The inclusion criteria were patients who underwent head and neck surgery without neck dissection and had a closed suction drain inserted. Drainage rates were measured at 8-hourly intervals. Drains were removed when drainage-rate was ≤ 1 ml/h over an 8-h period. A total of 43 patients were evaluated. The highest drainage rate occurred in the first 8 postoperative hours and decreased significantly in the subsequent hours. The median drainage rates at 8, 16, 24, 32 and 40 postoperative hours were 3.375, 1, 0, 0 and 0 ml/h, respectively. Applying our new removal criteria of ≤ 1 ml/h drainage rate, the drains were removed in 22 (51%) patients at the 16th postoperative hour; 37 (86%) were removed by 24 h after operation. In comparison, only nine (20.9%) patients could potentially be discharged the day after surgery if previous criteria of ≤ 25 ml/24-h were used to decide on drain removal. Our 8-hourly drainage-rate monitoring has facilitated safe earlier discharge of an additional 28 (65%) patients on the day after surgery. This has led to improvement in patient care, better optimisation of hospital resources and resulted in positive economic implications to the department.

  2. Stand growth 20 years after planting on Flakmossen - the significance of drainage and fertilization in an afforestation trial on a peat harvesting field in the province of Vaermland, West Central Sweden; Skogstillvaexten ca 20 aar efter plantering paa Flakmossen - dikningens och goedslingens betydelse vid beskogning paa en avslutad torvtaekt i Vaermland

    Energy Technology Data Exchange (ETDEWEB)

    Lehto, Bjoern

    2005-04-15

    This study was performed in an afforestation experiment established 1982 on an abandoned peat harvesting area, Flakmossen, in the province of Vaermland, SW Sweden. The experimental design include planting with Scots pine (Pinus sylvestris), in combination with various drainage intensities (20, 30, and 40 m between ditches), and fertilizer doses 0, 100, and 200 g PK per seedling applied at the date of planting. The aim of this study was to achieve more knowledge about the conditions on afforestation of peat harvesting areas, especially regarding drainage intensity and fertilization requirements, by means of determining the stand growth and yield in the Flakmossen trial. The forest growth did not differ significantly between the drainage intensities tested when the same amount of phosphor and potassium fertilizer was added. Thus, shorter distances between ditches than 40 m can not be recommended. When no fertilization was carried out seedling survival was very low, and the growth of survived seedlings was poor. The largest diameter and height growth were observed in the areas where the highest dose of phosphorus and potassium (200 g/seedling) was given. The results indicate that the average site growth capacity during a rotation period is 7-8 m{sup 3}/ha/yr. This is about 40 % higher than the average for all forest land in the province. The results indicate that afforestation of peat harvesting areas should be considered as effective land use.

  3. Leaching of plant protection products to field ditches in the Netherlands : development of a drainpipe scenario for arable land

    NARCIS (Netherlands)

    Tiktak, A.; Boesten, J.J.T.I.; Hendriks, R.F.A.; Linden, van der A.M.A.

    2012-01-01

    In the current Dutch authorisation procedure for calculating exposure of surface water organisms to plant protection products, deposition of drift is considered to be the only source. Drainage from agriclutural fields is being ignored. Because drainage may be an important source for exposure of

  4. Bathing littoral water pollution related to ditches fecal coliform concentration and load (first stage); Inquinamento delle acque litorali adibite alla balneazione in relazione alla concentrazione e al carico di coliformi fecali dei fossi (prima fase di studio)

    Energy Technology Data Exchange (ETDEWEB)

    Simoni, Franco [ARPAT, Lucca (Italy). Dipt. Provinciale U.O. Biologia Ambientale; Quilici, Mariachiara; Brunelli, Iacopo

    1997-08-01

    Fecal coliforms concentration and load, and flow of four ditches (Burlamacca, Abate, Motrone, Fiumetto) with mouth into Versilia coast have been studied. Superficial water environmental impact on surrounding sea-water (according to DPR 470/82) has been evaluated. During the study period (from April to September) these mouths behave like lagoons, showing negative positive or no flow, in relation both to the sea and to affluent waters hydrodynamic force. Positive correlation between mm of rain fallen during the week before the drawing and the number of FC/100 ml of ditches water has been pointed out, while there is no correlation with FC/100 ml of sea-water. Sea-water pollution is influenced by ditches flow a nd load of FC s{sup -1}; these two parameters are not correlated to rain, because it is often associated with sea-land wind. Fiumetto ditch is an exception, with its significant correlation index (r = 0.64). The correlation between the number of FC s{sup -1} of the ditches and the number of FC/100 ml of littoral water is significant for Burlamacca and Abate ditches (r > 0.63, p < 0.05). Burlamacca ditch produces greater fecal pollution (FC s{sup -1} = 247077332) than Motrone (FC {sup -1} = 5406436), Abate (FCs{sup -1} = 4114183) and Fiumetto (FCs{sup -1} 2201103) ditches.

  5. Gravity Drainage Kinetics of Papermaking Fibrous Suspensions

    Directory of Open Access Journals (Sweden)

    Przybysz Piotr

    2014-12-01

    Full Text Available The study analyses application possibilities of filtration and thickening models in evaluation of papermaking suspension drainage rate. The authors proposed their own method to estimate the drainage rate on the basis of an existing Ergun capillary model of liquid flow through a granular material. The proposed model was less sensitive to porosity changes than the Ergun model. An empirical verification proved robustness of the proposed approach. Taking into account discrepancies in the published data concerning how the drainage velocity of papermaking suspension is defined, this study examines which of the commonly applied models matches experimental results the best.

  6. The influence of environmental factors and dredging on chironomid larval diversity in urban drainage systems in polders strongly influenced by seepage from large rivers

    DEFF Research Database (Denmark)

    Vermonden, K.; Brodersen, Klaus Peter; Jacobsen, Dean

    2011-01-01

    , in urban waters strongly influenced by seepage of large rivers. Chironomid assemblages were studied in urban surface-water systems (man-made drainage ditches) in polder areas along lowland reaches of the rivers Rhine-Meuse in The Netherlands. Multivariate analysis was used to identify the key environmental...... factors. Taxon richness, Shannon index (H'), rareness of species, and life-history strategies at urban locations were compared with available data from similar man-made water bodies in rural areas, and the effectiveness of dredging for restoring chironomid diversity in urban waters was tested. Three...... diversity of chironomid communities in urban waters affected by nutrient-rich seepage or inlet of river water...

  7. The effect of long-term forestry drainage on the current state of peatland soils: A case study from the Central Sudetes, SW Poland

    Directory of Open Access Journals (Sweden)

    B. Glina

    2016-10-01

    Full Text Available One important need in the context of peatland restoration is to gain knowledge of soil organic matter quality and current soil-forming process in degraded peatlands. The aim of this study was to evaluate the impact of long-term drainage on soil transformation processes. In autumn 2012, soil survey and sampling was carried out on five shallow peatlands in the Central Sudeten Mountains (Poland which had been drained for forestry use in the late 1800s or early 1900s. Four organic soils (Histosols and one organo-mineral soil (Histic Gleysol were studied. The surface soil horizons were mainly transformed due to long-term forestry drainage. Increased aeration of these layers had enhanced their content of labile forms of carbon and they were undergoing secondary transformation. Soil transformation was more advanced in fen peatlands than in transitional mire or raised bogs. Only the fens exhibited characteristic evidence of the moorsh-forming process. Further drying of these soils will negatively affect their rewetting potential and significantly reduce the effective application of restoration treatments. In order to reduce organic matter transformation and loss from the investigated peatland areas, their drainage ditches should be blocked. Additionally, some trees should be removed from their central areas to reduce evapotranspiration.

  8. High-frequency monitoring of water fluxes and nutrient loads to assess the effects of controlled drainage on water storage and nutrient transport

    NARCIS (Netherlands)

    Rozemeijer, J.C.; Visser, A.; Borren, W.; Winegram, M.; Velde, Y. van der; Klein, J.; Broers, H.P.

    2016-01-01

    High nitrogen (N) and phosphorus (P) fluxes from upstream agriculture threaten aquatic ecosystems in surface waters and estuaries, especially in areas characterized by high agricultural N and P inputs and densely drained catchments like the Netherlands. Controlled drainage has been recognized as an

  9. Cholangitis following percutaneous biliary drainage

    International Nuclear Information System (INIS)

    Audisio, R.A.; Bozzetti, F.; Cozzi, G.; Severini, A.; Belloni, M.; Friggerio, L.F.

    1989-01-01

    The binomial PTBD-cholangitis often stands under different and sometimes even opposite relations. Among its indications the procedure lists, the treatment of cholangitis which, on the other hand, may be itself a complication of biliary drainage. The present work proposes a critical review of cholangitis-PTBD correlations, from an ordinary clinical-radiological point of view. Different pathogenetic hypothesis of cholangitis (inflammation, cholestasis, surgical manipulation) are discussed together with risk factors (impaired macrophagic-phagocytic system, immunosuppresion, wide neoplastic liver involvement, multiple intrahepatic ductal obstructions, chronic liver diseases, aged patients, etc.). The authors also report about prevention and treatment of septic complications which must be carried out following technical and therapeutic strategies, such as chemoprophylaxis and focused antibiotic therapy according to coltural samples, slow injection of small amounts of contrast medium, peripheral branches approach, gentle handling of catheters and guidewires, flushing with saline solutions and brushing of the catheter itself, and finally use of large gauge catheters in the presence of bile sludge

  10. Migratory bird habitat in relation to tile drainage and poorly drained hydrologic soil groups

    Science.gov (United States)

    Kastner, Brandi; Christensen, Victoria G.; Williamson, Tanja N.; Sanocki, Chris A.

    2016-01-01

    The Prairie Pothole Region (PPR) is home to more than 50% of the migratory waterfowl in North America. Although the PPR provides an abundance of temporary and permanent wetlands for nesting and feeding, increases in commodity prices and agricultural drainage practices have led to a trend of wetland drainage. The Northern Shoveler is a migratory dabbling duck species that uses wetland habitats and cultivated croplands in the PPR. Richland County in North Dakota and Roberts County in South Dakota have an abundance of wetlands and croplands and were chosen as the study areas for this research to assess the wetland size and cultivated cropland in relation to hydrologic soil groups for the Northern Shoveler habitat. This study used geographic information system data to analyze Northern Shoveler habitats in association with Natural Resource Conservation Service soil data. Habitats, which are spatially associated with certain hydrologic soil groups, may be at risk of artificial drainage installations because of their proximity to cultivated croplands and soil lacking in natural drainage that may become wet or inundated. Findings indicate that most wetlands that are part of Northern Shoveler habitats were within or adjacent to cultivated croplands. The results also revealed soil hydrologic groups with high runoff potential and low water transmission rates account for most of the soil within the Northern Shoveler‘s wetland and cropland habitats. Habitats near agriculture with high runoff potential are likely to be drained and this has the potential of reducing Northern Shoveler habitat.

  11. 4R Water Quality Impacts: An Assessment and Synthesis of Forty Years of Drainage Nitrogen Losses.

    Science.gov (United States)

    Christianson, L E; Harmel, R D

    2015-11-01

    The intersection of agricultural drainage and nutrient mobility in the environment has led to multiscale water quality concerns. This work reviewed and quantitatively analyzed nearly 1,000 site-years of subsurface tile drainage nitrogen (N) load data to develop a more comprehensive understanding of the impacts of 4R practices (application of the right source of nutrients, at the right rate and time, and in the right place) within drained landscapes across North America. Using drainage data newly compiled in the "Measured Annual Nutrient loads from AGricultural Environments" (MANAGE) database, relationships were developed across N application rates for nitrate N drainage loads and corn ( L.) yields. The lack of significant differences between N application timing or application method was inconsistent with the current emphasis placed on application timing, in particular, as a water quality improvement strategy ( = 0.934 and 0.916, respectively). Broad-scale analyses such as this can help identify major trends for water quality, but accurate implementation of the 4R approach will require site-specific knowledge to balance agronomic and environmental goals. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. Basics of Postural Drainage and Percussion

    Science.gov (United States)

    ... Active Cycle of Breathing Technique Airway Clearance Techniques Autogenic Drainage Basics of Lung Care Chest Physical Therapy ... care. Clinician Awards Clinician Career Development Awards Clinician Training Awards Mutation Analysis Program Network News Network News: ...

  13. Rye cover crop and gamagrass strip effects on NO3 concentration and load in tile drainage.

    Science.gov (United States)

    Kaspar, T C; Jaynes, D B; Parkin, T B; Moorman, T B

    2007-01-01

    A significant portion of the NO3 from agricultural fields that contaminates surface waters in the Midwest Corn Belt is transported to streams or rivers by subsurface drainage systems or "tiles." Previous research has shown that N fertilizer management alone is not sufficient for reducing NO3 concentrations in subsurface drainage to acceptable levels; therefore, additional approaches need to be devised. We compared two cropping system modifications for NO3 concentration and load in subsurface drainage water for a no-till corn (Zea mays L.)-soybean (Glycine max [L.] Merr.) management system. In one treatment, eastern gamagrass (Tripsacum dactyloides L.) was grown in permanent 3.05-m-wide strips above the tiles. For the second treatment, a rye (Secale cereale L.) winter cover crop was seeded over the entire plot area each year near harvest and chemically killed before planting the following spring. Twelve 30.5x42.7-m subsurface-drained field plots were established in 1999 with an automated system for measuring tile flow and collecting flow-weighted samples. Both treatments and a control were initiated in 2000 and replicated four times. Full establishment of both treatments did not occur until fall 2001 because of dry conditions. Treatment comparisons were conducted from 2002 through 2005. The rye cover crop treatment significantly reduced subsurface drainage water flow-weighted NO3 concentrations and NO3 loads in all 4 yr. The rye cover crop treatment did not significantly reduce cumulative annual drainage. Averaged over 4 yr, the rye cover crop reduced flow-weighted NO3 concentrations by 59% and loads by 61%. The gamagrass strips did not significantly reduce cumulative drainage, the average annual flow-weighted NO3 concentrations, or cumulative NO3 loads averaged over the 4 yr. Rye winter cover crops grown after corn and soybean have the potential to reduce the NO3 concentrations and loads delivered to surface waters by subsurface drainage systems.

  14. Groundwater recharge and agricultural contamination

    Science.gov (United States)

    Böhlke, J.K.

    2002-01-01

    Agriculture has had direct and indirect effects on the rates and compositions of groundwater recharge and aquifer biogeochemistry. Direct effects include dissolution and transport of excess quantities of fertilizers and associated materials and hydrologic alterations related to irrigation and drainage. Some indirect effects include changes in water–rock reactions in soils and aquifers caused by increased concentrations of dissolved oxidants, protons, and major ions. Agricultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO3–, N2, Cl, SO42–, H+, P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well as a wide variety of pesticides and other organic compounds. For reactive contaminants like NO3–, a combination of chemical, isotopic, and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. Groundwater records derived from multi-component hydrostratigraphic data can be used to quantify recharge rates and residence times of water and dissolved contaminants, document past variations in recharging contaminant loads, and identify natural contaminant-remediation processes. These data indicate that many of the world's surficial aquifers contain transient records of changing agricultural contamination from the last half of the 20th century. The transient agricultural groundwater signal has important implications for long-term trends and spatial heterogeneity in discharge.

  15. Scintigraphy of the lacrimal drainage system

    International Nuclear Information System (INIS)

    Denffer, H. von; Dressler, J.; Technische Univ. Muenchen

    1978-01-01

    A new scintigraphic method, the radionuclide dacryography, to evaluate lacrimal drainage and its disorders is described. A drop of sup(99m)Tc-pertechnetate is dropped onto the eyes and the transport of the nuclide is registered by a scintillation camera. By this method it is easy to verify, under physiological conditions, suspected obstructions of the lacrimal drainage system and to determine its localization. The absorbed radiation dose using radionuclide dacryography is very low as compared to radiological methods. (orig.) [de

  16. Pressure Jumps during Drainage in Macroporous Soils

    DEFF Research Database (Denmark)

    Soto, Diego; Paradelo Pérez, Marcos; Corral, A

    2018-01-01

    Tensiometer readings obtained at high resolution during drainage of structured soil columns revealed pressure jumps with long range correlations and burst sequences with a hierarchical structure. The statistical properties of jumps are similar to Haines jumps described in invasion percolation...... processes at pore scale, but they are much larger in amplitude and duration. Pressure jumps can result from transient redistribution of water potential in internal regions of soil and can be triggered during drainage by capillary displacements at the scale of structural pores....

  17. Are there still roles for exocrine bladder drainage and portal venous drainage for pancreatic allografts?

    Science.gov (United States)

    Young, Carlton J

    2009-02-01

    Controversy remains regarding the best methodology of handling exocrine pancreatic fluid and pancreatic venous effluent. Bladder drainage has given way to enteric drainage. However, is there an instance in which bladder drainage is preferable? Also, hyperinsulinemia, as a result of systemic venous drainage (SVD), is claimed to be proatherosclerotic, whereas portal venous drainage (PVD) is more physiologic and less atherosclerotic. Bladder drainage remains a viable method of exocrine pancreas drainage, but evidence is sparse that measuring urinary amylase has a substantial benefit in the early detection of acute rejection in all types of pancreas transplants. Currently, there is no incontrovertible evidence that systemic hyperinsulinemia is proatherosclerotic, whereas recent metabolic studies on SVD and PVD showed that there was no benefit to PVD. Given the advent of newer immunosuppressive agents and overall lower acute rejection rates, the perceived benefit of bladder drainage as a means to measure urinary amylase as an early marker of rejection has not been substantiated. However, there may be a selective role for bladder drainage in 'high risk' pancreases. Also, without a clear-cut metabolic benefit to PVD over SVD, it remains the surgeon's choice as to which method to use.

  18. Agricultural problems

    International Nuclear Information System (INIS)

    Bickerton, George E.

    1997-01-01

    Although there were not reasons to deplore against major activity release from any of the 110 industrial reactors authorized to operate in US, the nuclear incident that occurred at the Three Mile Island Plant in 1979 urged the public conscience toward the necessity of readiness to cope with events of this type. The personnel of the Emergency Planning Office functioning in the frame of US Department of Agriculture has already participated in around 600 intervention drillings on a federal, local or state scale to plan, test or asses radiological emergency plans or to intervene locally. These exercises allowed acquiring a significant experience in elaborating emergency plans, planning the drillings, working out scenarios and evaluation of the potential impact of accidents from the agricultural point of view. We have also taken part in different international drillings among which the most recent are INEX 1 and RADEX 94. We have found on these occasions that the agricultural problems are essential preoccupations in most of the cases no matter if the context is international, national, local or of state level. The paper poses problems specifically related to milk, fruits and vegetables, soils, meat and meat products. Finally the paper discusses issues like drilling planning, alarm and notification, sampling strategy, access authorizations for farmers, removing of contamination wastes. A number of social, political and economical relating problems are also mentioned

  19. Water and nutrient budgets at field and regional scale : travel times of drainage water and nutrient loads to surface water

    NARCIS (Netherlands)

    Eertwegh, van den G.A.P.H.

    2002-01-01

    Keywords : water and nutrient budget, travel time of drainage water, dual-porosity concept, agricultural nutrient losses, loads to surface water, field-scale experiments, regional-scale

  20. Impact of Tile Drainage on the Distribution of Concentration and Age of Inorganic Soil Nitrogen.

    Science.gov (United States)

    Woo, D.; Kumar, P.

    2017-12-01

    Extensive network of tile drainage network across the Midwestern United States, northern Europe and other regions of the world have enhanced agricultural productivity. Because of its impact on sub-surface flow patterns and moisture and temperature dynamics, it controls the nitrogen cycle in agricultural systems, and its influence on nitrogen dynamics plays a key role in determining the short- and long-term evolution of soil inorganic nitrogen concentration and age. The spatial mapping of nitrogen concentration and age under tile-drained fields has, therefore, the potential to open up novel solution to the vexing challenge of reducing environmental impacts while at the same time maintaining agricultural productivity. The objective of this study is to explore the impacts of tile drains on the age dynamics of nitrate, immobile ammonium, mobile ammonia/um, and non-reactive tracer (such as chloride) by implementing two mobile interacting pore domains to capture matrix and preferential flow paths in a coupled ecohydrology and biogeochemistry model, Dhara. We applied this model to an agricultural farm supporting a corn-soybean rotation in the Midwestern United States. It should be expected that the installation of tile drains decrease the age of soil nutrient due to nutrient losses through tile drainage. However, an increase in the age of mobile ammonia/um is observed in contrast to the cases for nitrate, immobile ammonium, and non-reactive tracer. These results arise because the depletion of mobile ammonia/um due to tile drainage causes a high mobility flux from immobile ammonium to mobile ammonia/um, which also carries a considerable amount of relatively old age of immobile ammonium to mobile ammonia/um. In addition, the ages of nitrate and mobile ammonia/um in tile drainage range from 1 to 3 years, and less than a year, respectively, implying that not considering age transformations between nitrogen species would result in substantial underestimation of nitrogen ages

  1. Failures and complications of thoracic drainage

    Directory of Open Access Journals (Sweden)

    Đorđević Ivana

    2006-01-01

    Full Text Available Background/Aim. Thoracic drainage is a surgical procedure for introducing a drain into the pleural space to drain its contents. Using this method, the pleura is discharged and set to the physiological state which enables the reexpansion of the lungs. The aim of the study was to prove that the use of modern principles and protocols of thoracic drainage significantly reduces the occurrence of failures and complications, rendering the treatment more efficient. Methods. The study included 967 patients treated by thoracic drainage within the period from January 1, 1989 to June 1, 2000. The studied patients were divided into 2 groups: group A of 463 patients treated in the period from January 1, 1989 to December 31, 1994 in whom 386 pleural drainage (83.36% were performed, and group B of 602 patients treated form January 1, 1995 to June 1, 2000 in whom 581 pleural drainage (96.51% were performed. The patients of the group A were drained using the classical standards of thoracic drainage by the general surgeons. The patients of the group B, however, were drained using the modern standards of thoracic drainage by the thoracic surgeons, and the general surgeons trained for this kind of the surgery. Results. The study showed that better results were achieved in the treatment of the patients from the group B. The total incidence of the failures and complications of thoracic drainage decreased from 36.52% (group A to 12.73% (group B. The mean length of hospitalization of the patients without complications in the group A was 19.5 days versus 10 days in the group B. The mean length of the treatment of the patients with failures and complications of the drainage in the group A was 33.5 days versus 17.5 days in the group B. Conclusion. The shorter length of hospitalization and the lower morbidity of the studied patients were considered to be the result of the correct treatment using modern principles of thoracic drainage, a suitable surgical technique, and a

  2. Monitoring-based analysis of agriculture in Iraq

    OpenAIRE

    Tokareva, Olga Sergeevna; Pasko, Olga Anatolievna; Alshaibi, A.; Mochalov, M.

    2016-01-01

    The paper deals with change in area and structure of Iraq agricultural lands. It revealed the main reasons for the change: crisis (war, sanctions, etc.); economic (swamp and lake drainage, melioration, etc.); weather condition. Land-use intensification as a reason for reduction of agricultural land areas was not proved. The area of cultivated lands proved to correlate significantly with the level of precipitation, wheat productivity -with the average temperature in Iraq.

  3. Iron precipitations in the Lusatian lignite district. Pt. 1: water pumpage and water drainage in the opencast mine of Nochten, hydrochemistry of mine water; Eisenausfaellungen im Lausitzer Braunkohlerevier. T. 1: Wasserhebung und -ableitung im Tagebau Nochten, Hydrochemie der Suempfungswaesser

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, I. [LAUBAG, Senftenberg (Germany); Uhlmann, W. [IWB - Institut fuer Wasser und Boden, Dresden (Germany)

    2002-09-01

    Opencast lignite mines are subject to permanent drainage. Due to iron disulphide weathering, drainage waters are acidic and rich in ferrous iron and sulphate. In the case of the mine Nochten (Lusatia, East Germany) the originating water is directed from the mine through several open ditches and finally through a pipeline to reach to purification plant at a distance of 14 km. During this course part of the ferrous iron is oxidised to form ferric iron, which precipitates as Fe(III)-minerals. The iron loss in the drainage system between the open cast Nochten to the purification plant Schwarze Pumpe is 30-37% under summer conditions and 18% under winter conditions. Especially for the pipeline these precipitates represent a serious problem, as they result in incrustations and therefore in decreased discharge rates. This article focuses on the hydrochemical processes occurring during the discharge of water to the purification plant. Investigations were based on hydrochemical measurements in the drainage systems as well as on laboratory experiments on the oxidation kinetics of ferrous iron. These resulted in the following findings: (1) The oxidation of ferrous iron in the acidic waters is slow even at oxygen concentrations near saturation. Thus, oxygen is not the limiting factor for the oxidation process. (2) Oxidation kinetics are strongly dependent on temperature. Conclusively, a reduction of iron precipitates may be achieved firstly by shortening the distance of the transport course and secondly by preventing a warming up of waters in summer. (orig.)

  4. Percutaneous drainage of abscesses associated with biliary fistulae

    International Nuclear Information System (INIS)

    Berger, H.; Winter, T.; Pratschke, E.; Sauerbruch, T.; Klinikum Grosshadern, Muenchen; Klinikum Grosshadern, Muenchen

    1989-01-01

    33 abdominal abscesses associated with fistulae in 31 patients were treated by percutaneous drainage. 19 of these patients had had surgery immediately preceding the drainage. In 64% the percutaneous drainage led to a diagnosis of an internal fistula. Additional therapeutic measures, because of the fistula, were necessary in 45% (operation, biliary drainage, repositioning of catheter). The average duration of drainage was 29 days. 77% of those abscesses which could be drained were treated successfully. Mortality in the entire series was 19%. (orig.) [de

  5. Open Drainage and Detention Basin Combined System Optimization

    Directory of Open Access Journals (Sweden)

    M. E. Banihabib

    2017-01-01

    basin and the narrower valley. After the initial selection of dam sites, based on the reservoir volume to construction volume ratio of each dam site, best sites were selected to have the higher ratio. The layout of the main drainage scheme that is responsible for collecting and transferring overland flows of farmlands and reservoir outflows was designed. In order to simulate the hydrological processes in upstream watershed and flood analysis, HEC-HMS model which is an extended version of HEC-1 was used as hydrologic model. The optimal combination of open drainages and detention basins was also developed. Watershed in terms of detention basin dams, topography and drainage were divided into 19 smaller sub-basins. The downstream agricultural basin due to the slope and drainage area was divided into 27 sub-basins. Regarding available information of the watershed, SCS method was used to calculate losses and to convert rainfall to runoff hydrograph. In this section Muskingum flood routing method was used considering its accuracy. In the present optimization model, the total cost of the combined system of dams and open drains used as the objective function. It is function bottom outlet diameter which is minimized by using optimization model. Other factors of the simulation model such as dam height and drainage dimensions were defined as function of the diameter of the bottom outlet of dams. After determining the optimal dimensions of the combined system of open drainage and detention basins, a sensitivity analysis was performed on hydrological factors. Results and Discussion: After optimization of the dimensions of open drainage and detention basin integrated-system, sensitivity analysis was carried out on the dimensions of system for variation of flood simulation parameters such as rainfall, curve number and lag time. The error of estimated rainfall effected far less than the curve number (CN on the optimum dimensions and cost. 10% variation of the rainfall depth caused

  6. 2016 Annual Industrial Wastewater Reuse Report for the Idaho National Laboratory Site’s Materials and Fuels Complex Industrial Waste Ditch and Industrial Waste Pond

    Energy Technology Data Exchange (ETDEWEB)

    Cafferty, Kara Grace [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-02-01

    This report describes conditions, as required by the state of Idaho Industrial Wastewater Reuse Permit (WRU-I-0160-01, Modification 1, formerly LA 000160 01), for the wastewater reuse site at the Idaho National Laboratory Site’s Materials and Fuels Complex Industrial Waste Ditch and Industrial Waste Pond from November 1, 2015, through October 31, 2016.

  7. Competition of a parathion-hydrolyzing Flavobacterium with bacteria from ditch water in carbon-, nitrate- and phosphate-limited continuous cultures

    NARCIS (Netherlands)

    Sprenger, W.; Dijkstra, A.; Zwart, G.; Van Agterveld, M.P.; Van Noort, P.C.M.; Parsons, J.R.

    2003-01-01

    The effect of competition for macroelements with bacteria from ditch water on the parathion-hydrolyzing Flavobacterium sp. ATCC 27551 (FB) was investigated within mixed continuous cultures under carbon-, nitrate- or phosphate-limited conditions. The high initial rate of parathion hydrolysis

  8. 2016 Annual Industrial Wastewater Reuse Report for the Idaho National Laboratory Site's Materials and Fuels Complex Industrial Waste Ditch and Industrial Waste Pond

    International Nuclear Information System (INIS)

    Cafferty, Kara Grace

    2017-01-01

    This report describes conditions, as required by the state of Idaho Industrial Wastewater Reuse Permit (WRU-I-0160-01, Modification 1, formerly LA 000160 01), for the wastewater reuse site at the Idaho National Laboratory Site's Materials and Fuels Complex Industrial Waste Ditch and Industrial Waste Pond from November 1, 2015, through October 31, 2016.

  9. Fate of the insecticide lambda-cyhalothrin in ditch enclosures differing in vegetation density

    NARCIS (Netherlands)

    Leistra, M.; Zweers, A.J.; Warinton, J.S.; Crum, S.J.H.; Hand, L.H.; Beltman, W.H.J.; Maund, S.J.

    2004-01-01

    Use of the insecticide lambda-cyhalothrin in agriculture may result in the contamination of water bodies, for example by spray drift. Therefore, the possible exposure of aquatic organisms to this insecticide needs to be evaluated. The exposure of the organisms may be reduced by the strong sorption

  10. Spatiotemporal variation of plant diversity on ditch banks under different management regimes

    NARCIS (Netherlands)

    Leng, X.; Musters, C.J.M.; Snoo, de G.R.

    2011-01-01

    Agricultural intensification has led to a loss of biological diversity at various spatial and temporal scales and understanding the mechanisms driving these changes would help target conservation efforts accordingly. In this study we used additive partitioning of diversity and the Jaccard index of

  11. Improved drainage with active chest tube clearance.

    Science.gov (United States)

    Shiose, Akira; Takaseya, Tohru; Fumoto, Hideyuki; Arakawa, Yoko; Horai, Tetsuya; Boyle, Edward M; Gillinov, A Marc; Fukamachi, Kiyotaka

    2010-05-01

    This study was performed to evaluate the efficacy of a novel chest drainage system. This system employs guide wire-based active chest tube clearance to improve drainage and maintain patency. A 32 Fr chest tube was inserted into pleural cavities of five pigs. On the left, a tube was connected to the chest canister, and on the right, the new system was inserted between the chest tube and chest canister. Acute bleeding was mimicked by periodic infusion of blood. The amount of blood drained from each chest cavity was recorded every 15 min for 2 h. After completion of the procedure, all residual blood and clots in each chest cavity were assessed. The new system remained widely patent, and the amount of drainage achieved with this system (670+/-105 ml) was significantly (P=0.01) higher than that with the standard tube (239+/-131 ml). The amount of retained pleural blood and clots with this system (150+/-107 ml) was significantly (P=0.04) lower than that with the standard tube (571+/-248 ml). In conclusion, a novel chest drainage system with active tube clearance significantly improved drainage without tube manipulations. 2010 Published by European Association for Cardio-Thoracic Surgery. All rights reserved.

  12. Monitoring and Assessment of Water Retention Measures in Agricultural Land

    Science.gov (United States)

    Výleta, Roman; Danáčová, Michaela; Škrinár, Andrej; Fencík, Róbert; Hlavčová, Kamila

    2017-12-01

    One of the most interesting events, from the environmental impact point of view, is the huge storm rainfall at which soil degradation processes occur. In Slovakia, agricultural areas with a higher slope have been recently increasingly denudated by water erosion processes. Areas having regular problems with muddy floods and denudation of soil particles have been currently identified. This phenomenon has long-term adverse consequences in the agricultural landscape, especially the decline in soil fertility, the influence on soil type and the reduction of depth of the soil profile. In the case of storm rainfall or long-term precipitation, soil particles are being transported and deposited at the foot of the slope, but in many cases the large amounts of sediment are transported by water in the form of muddy floods, while putting settlements and industrial zones at risk, along with contamination and clogging of watercourses and water reservoirs. These unfavourable phenomena may be prevented by appropriate management and application of technical measures, such as water level ditches, erosion-control weirs, terraces and others. The study deals with determination of the soil loss and denudation of soil particles caused by water erosion, as well as with determination of the volume of the surface runoff created by the regional torrential rains in the area of the village of Sobotište. The research is based on the analysis of flood and erosion-control measures implemented in this area. Monitoring of these level ditches for protection against muddy floods has been carried out since 2015 using UAV technology and terrestrial laser scanning. Monitoring is aimed on determination of the volume of the ditch, changes in its capacity and shape in each year. The study evaluates both the effectiveness of these measures to reduce the surface runoff as well as the amount of eroded soil particles depending on climatological conditions. The results of the research point to the good

  13. Surface runoff and tile drainage transport of phosphorus in the midwestern United States.

    Science.gov (United States)

    Smith, Douglas R; King, Kevin W; Johnson, Laura; Francesconi, Wendy; Richards, Pete; Baker, Dave; Sharpley, Andrew N

    2015-03-01

    The midwestern United States offers some of the most productive agricultural soils in the world. Given the cool humid climate, much of the region would not be able to support agriculture without subsurface (tile) drainage because high water tables may damage crops and prevent machinery usage in fields at critical times. Although drainage is designed to remove excess soil water as quickly as possible, it can also rapidly transport agrochemicals, including phosphorus (P). This paper illustrates the potential importance of tile drainage for P transport throughout the midwestern United States. Surface runoff and tile drainage from fields in the St. Joseph River Watershed in northeastern Indiana have been monitored since 2008. Although the traditional concept of tile drainage has been that it slowly removes soil matrix flow, peak tile discharge occurred at the same time as peak surface runoff, which demonstrates a strong surface connection through macropore flow. On our research fields, 49% of soluble P and 48% of total P losses occurred via tile discharge. Edge-of-field soluble P and total P areal loads often exceeded watershed-scale areal loadings from the Maumee River, the primary source of nutrients to the western basin of Lake Erie, where algal blooms have been a pervasive problem for the last 10 yr. As farmers, researchers, and policymakers search for treatments to reduce P loading to surface waters, the present work demonstrates that treating only surface runoff may not be sufficient to reach the goal of 41% reduction in P loading for the Lake Erie Basin. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  14. [Off-line control of runoff pollution by filtering ditch-pond system in urban tourist areas].

    Science.gov (United States)

    Chen, Qing-Feng; Shan, Bao-Qing; Yin, Cheng-Qing; Hu, Cheng-Xiao

    2007-10-01

    An off-line filtering ditch-pond system for controlling storm runoff pollution in urban tourist areas was developed, which could retain the first flush effectively, resulting in the decrease of pollutant concentration and suspended solid average grain size, and the improvement of pollutant retention in runoff. This system could be an effective treatment system for storm runoff pollution, particularly for the scarcity of available land use in urban areas. In 2005, the yearly retention rates of TSS, COD, TN and TP were 86.4%, 85.5%, 83.9% and 82.9%, and during a storm event on June 26, the retention rates of runoff volume, TSS, COD, TN and TP were 67.9%, 97.0%, 89.2%, 94.9% and 96.2%, respectively. This system could also retain most of the suspended solids in runoff.

  15. Endoscopic Ultrasound-Guided Biliary Drainage

    International Nuclear Information System (INIS)

    Artifon, Everson L.A.; Ferreira, Fla'vio C.; Sakai, Paulo

    2012-01-01

    To demonstrate a comprehensive review of published articles regarding endoscopic ultrasound (EUS)-guided biliary drainage. Review of studies regarding EUS-guided biliary drainage including case reports, case series and previous reviews. EUS-guided hepaticogastrostomy, coledochoduodenostomy and choledoantrostomy are advanced biliary and pancreatic endoscopy procedures, and together make up the echo-guided biliary drainage. Hepaticogastrostomy is indicated in cases of hilar obstruction, while the procedure of choice is the coledochoduodenostomy or choledochoantrostomy in distal lesions. Both procedures must be performed only after unsuccessful ERCPs. The indication of these procedures must be made under a multidisciplinary view while sharing information with the patient or legal guardian. Hepaticogastrostomy and coledochoduodenostomy or choledochoantrostomy are feasible when performed by endoscopists with expertise in biliopancreatic endoscopy. Advanced echo-endoscopy should currently be performed under a rigorous protocol in educational institutions.

  16. Endoscopic Ultrasound-Guided Biliary Drainage

    Energy Technology Data Exchange (ETDEWEB)

    Artifon, Everson L.A.; Ferreira, Fla& #x27; vio C.; Sakai, Paulo [University of Saeo Paulo, Saeo Paulo (Brazil)

    2012-02-15

    To demonstrate a comprehensive review of published articles regarding endoscopic ultrasound (EUS)-guided biliary drainage. Review of studies regarding EUS-guided biliary drainage including case reports, case series and previous reviews. EUS-guided hepaticogastrostomy, coledochoduodenostomy and choledoantrostomy are advanced biliary and pancreatic endoscopy procedures, and together make up the echo-guided biliary drainage. Hepaticogastrostomy is indicated in cases of hilar obstruction, while the procedure of choice is the coledochoduodenostomy or choledochoantrostomy in distal lesions. Both procedures must be performed only after unsuccessful ERCPs. The indication of these procedures must be made under a multidisciplinary view while sharing information with the patient or legal guardian. Hepaticogastrostomy and coledochoduodenostomy or choledochoantrostomy are feasible when performed by endoscopists with expertise in biliopancreatic endoscopy. Advanced echo-endoscopy should currently be performed under a rigorous protocol in educational institutions.

  17. Bronchoscopic drainage of a malignant lung abscess.

    Science.gov (United States)

    Katsenos, Stamatis; Psathakis, Konstantinos; Chatzivasiloglou, Fotini; Antonogiannaki, Elvira-Markela; Psara, Anthoula; Tsintiris, Konstantinos

    2015-04-01

    Bronchoscopic drainage of a pyogenic lung abscess is an established therapeutic approach in selected patients in whom conventional antibiotic therapy fails. This intervention has also been undertaken in patients with abscess owing to underlying lung cancer and prior combined radiochemotherapy. However, this procedure has rarely been performed in cavitary lesions of advanced tumor origin before initiating any chemotherapy/radiotherapy scheme. Herein, we describe a case of a 68-year-old woman with lung adenocarcinoma stage IIIB, who underwent bronchoscopic drainage of necrotizing tumor lesion, thus improving her initial poor clinical condition and rendering other treatment modalities, such as radiotherapy, more effective and beneficial. Bronchoscopic drainage of a symptomatic cancerous lung abscess should be considered as an alternative and palliative treatment approach in patients with advanced inoperable non-small cell lung cancer.

  18. Glaucoma Drainage Device Erosion Following Ptosis Surgery.

    Science.gov (United States)

    Bae, Steven S; Campbell, Robert J

    2017-09-01

    To highlight the potential risk of glaucoma drainage device erosion following ptosis surgery. Case report. A 71-year-old man underwent uncomplicated superotemporal Ahmed glaucoma valve implantation in the left eye in 2008. Approximately 8 years later, the patient underwent bilateral ptosis repair, which successfully raised the upper eyelid position. Three months postoperatively, the patient's glaucoma drainage implant tube eroded through the corneal graft tissue and overlying conjunctiva to become exposed. A graft revision surgery was successfully performed with no further complications. Caution and conservative lid elevation may be warranted when performing ptosis repair in patients with a glaucoma drainage implant, and patients with a glaucoma implant undergoing ptosis surgery should be followed closely for signs of tube erosion.

  19. Managing a chest tube and drainage system.

    Science.gov (United States)

    Durai, Rajaraman; Hoque, Happy; Davies, Tony W

    2010-02-01

    Intercostal drainage tubes (ie, chest tubes) are inserted to drain the pleural cavity of air, blood, pus, or lymph. The water-seal container connected to the chest tube allows one-way movement of air and liquid from the pleural cavity. The container should not be changed unless it is full, and the chest tube should not be clamped unnecessarily. After a chest tube is inserted, a nurse trained in chest-tube management is responsible for managing the chest tube and drainage system. This entails monitoring the chest-tube position, controlling fluid evacuation, identifying when to change or empty the containers, and caring for the tube and drainage system during patient transport. This article provides an overview of indications, insertion techniques, and management of chest tubes. Copyright 2010 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  20. East Saint Louis and Vicinity, Illinois. Blue Waters Ditch Improvements. Final Environmental Statement.

    Science.gov (United States)

    1978-06-01

    2.1.7 CLIMATOLOGICAL ELEMENTS OF THE AMERICAN BOTTOMS 2.1.7.1 General The climate of the American Bottoms and the Blue Waters area is that of the...land be sold by the owner for urban developnient. The older farmers express an intention to remain in the alea even in the event of farm loss. Each...land use is pastureland for grazing. Such livestock activities, though important in St. Clair County agriculture, are totally lacking in the Blue

  1. An economic case for drainage for sustainable irrigation: Case studies in the lower Vaal and Riet catchments

    Directory of Open Access Journals (Sweden)

    RJ Armour

    2014-05-01

    Full Text Available Where evaporation exceeds precipitation salinisation is inevitable. This paper presents a multidisciplinary framework of the dynamic interactions between the hydrology, bio-physical and economics of irrigated agriculture in a semi arid area. Status quo drainage and cropping situations are compared to a scenario of increased drainage and leaching and subsequent higher value crops. Stochastically generated hydrology data fitted to a salinisation:yield production function is inputted in a crop enterprise budget (CEB simulation model.Results show losses due to salinisation of up to R6 962/ha, which exceed the direct costs of installing drainage to control salinisation. Although feasible, farmers at this stage of degradation often do not have the financial ability to repay the loans. Where losses do not exceed the financial costs of drainage, soils are further degrading, higher value crops cannot be planted and potential benefits are lost to society, motivating a green box grant. A macro-economic analysis reveals that the potential benefits to society of drainage can repay the total cost of all necessary drainage in a short period of time.

  2. CT-guided biopsies and drainage

    International Nuclear Information System (INIS)

    Scheppers, I.; Wollschlaeger, D.

    2011-01-01

    Following the implementation of computed tomography (CT) or ultrasound-guided biopsy of solid tumors and the puncture and drainage of liquid processes, the number of surgical open biopsies and curative operations for abscess drainage has declined. Such CT-guided interventions are performed in nearly every organ. Instead of aspiration biopsies, more and more core biopsies are being performed to allow histopathological evaluation and thus allowing targeted therapy. This article is intended to give a general overview of techniques, materials, indications and contraindications. Ultrasound-guided biopsies as well as large bore vacuum biopsies of the breast are not included in this review. (orig.) [de

  3. Percutaneous transhepatic biliary drainage for hilar cholangiocarcinoma

    International Nuclear Information System (INIS)

    Qian Xiaojun; Jin Wenhui; Dai Dingke; Yu Ping; Gao Kun; Zhai Renyou

    2007-01-01

    Objective: To evaluate the effect of PTBD in treating malignant biliary obstruction caused by hilar cholangiocarcinoma. Methods: We retrospectively analyzed the data of 103 patients(M:62,F:41)with malignant obstructive jaundice caused by hilar cholangiocarcinoma. After taking percutaneous transhepatic cholangiography, metallic stent or plastic external catheter or external-internal catheter for drainage was deployed and then followed up was undertaken with clinical and radiographic evaluation and laboratory. examination. Results: All patients went though PTBD successfully (100%). According to Bismuth classification, all 103 cases consisted of I type(N=30), II type (N=30), III type (N=26) and IV type (N=17). Thirty-nine cases were placed with 47 stents and 64 eases with drainage tubes. 4 cases installed two stems for bilateral drainage, 2 cases installed two stents because of long segmental strictures with stent in stent, 1 case was placed with three stents, and 3 cases installed stent and plastic catheter together. Sixty-four cases received plastic catheters in this series, 35 cases installed two or more catheters for bilateral drainage, 28 cases installed external and internal drainage catheters, 12 eases installed external drainage catheters, and 24 eases installed both of them. There were 17 patients involving incorporative infection before procedure, 13 cases cured after procedure, and 15 new patients got inflammation after procedure. 13 cases showed increase of amylase (from May, 2004), 8 eases had bloody bile drainage and 1 case with pyloric obstruction. Total serum bilirubin reduced from (386 ± 162) μmol/L to (161 ± 117) μmol/L, (P<0.01) short term curative effect was related with the type of hilar cholangiocarcinoma. The survival time was 186 days(median), and 1, 3, 6, 12 month survival rate were 89.9%, 75.3%, 59.6%, 16.9%, respectively. Conclusion: Percutaneous transhepatic bile drainage is a safe and effective palliative therapy of malignant

  4. Urban drainage models - making uncertainty analysis simple

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Mikkelsen, Peter Steen; Deletic, Ana

    2012-01-01

    in each measured/observed datapoint; an issue which is commonly overlook in the uncertainty analysis of urban drainage models. This comparison allows the user to intuitively estimate the optimum number of simulations required to conduct uncertainty analyses. The output of the method includes parameter......There is increasing awareness about uncertainties in modelling of urban drainage systems and, as such, many new methods for uncertainty analyses have been developed. Despite this, all available methods have limitations which restrict their widespread application among practitioners. Here...

  5. Percutaneous catheter drainage of pancreatic pseudocysts

    International Nuclear Information System (INIS)

    Karnel, F.; Gebauer, A.; Jantsch, H.; Prayer, L.; Schurawitzki, H.; Feil, W.

    1991-01-01

    The results of CT/US-guided percutaneous drainage in 35 patients with pancreatic pseudocysts are reported. 27 patients recovered without surgery and no further treatment was required. 8 patients required a subsequent surgery due to recurrence. The role of CT/US-guided percutaneous drainage in pancreatic pseudocysts as well as an analysis of the technical aspects associated with a successful procedure are discussed. Although US may be used, we believe CT is safer and allows more precise localisation and guidance in the treatment of pseudocysts. (orig.) [de

  6. Transanal Drainage of Coloanal Anastomotic Leaks

    Directory of Open Access Journals (Sweden)

    Bradley Sherman

    2018-01-01

    Full Text Available The conventional operative intervention for leaks following coloanal anastomoses has been proximal fecal diversion with or without take-down of anastomosis. A few of these cases are also amenable to percutaneous drainage. Ostomies created in this situation are often permanent, specifically in cases where coloanal anastomoses are taken down at the time of reoperation. We present two patients who developed perianastomotic pelvic abscesses that were treated with transanal large bore catheter drainage resulting in successful salvage of coloanal anastomoses without the need for a laparotomy or ostomy creation. We propose this to be an effective therapeutic approach to leaks involving low coloanal anastomoses in the absence of generalized peritonitis.

  7. Comparison of natural drainage group and negative drainage groups after total thyroidectomy: prospective randomized controlled study.

    Science.gov (United States)

    Woo, Seung Hoon; Kim, Jin Pyeong; Park, Jung Je; Shim, Hyun Seok; Lee, Sang Ha; Lee, Ho Joong; Won, Seong Jun; Son, Hee Young; Kim, Rock Bum; Son, Young-Ik

    2013-01-01

    The aim of this study was to compare a negative pressure drain with a natural drain in order to determine whether a negative pressure drainage tube causes an increase in the drainage volume. Sixty-two patients who underwent total thyroidectomy for papillary thyroid carcinoma (PTC) were enrolled in the study between March 2010 and August 2010 at Gyeongsang National University Hospital. The patients were prospectively and randomly assigned to two groups, a negative pressure drainage group (n=32) and natural drainage group (n=30). Every 3 hours, the volume of drainage was checked in the two groups until the tube was removed. The amount of drainage during the first 24 hours postoperatively was 41.68 ± 3.93 mL in the negative drain group and 25.3 ± 2.68 mL in the natural drain group (pdrain group was 35.19 ± 4.26 mL and natural drain groups 21.53 ± 2.90 mL (pdrain may increase the amount of drainage during the first 24-48 hours postoperatively. Therefore, it is not necessary to place a closed suction drain when only a total thyroidectomy is done.

  8. Practical Significance of Basin Water Market Construction on Agricultural Production

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    On the basis of introducing the concept of water market and the water market research in cluding both domestic market and foreign market,the system design features of water market are analyzed.The features include the prior distribution of agricultural water right,the close construction of market structure,reasonable price of water obtaining right and water pollution-discharge right and scientific stipulation of total volume of water use and total volume of pollution drainage.The practical significances of basin water market construction on Chinese agricultural production are revealed,which clover safeguarding the safety of agricultural water;effectively alleviating agricultural drought;saving the agricultural production water and improving the quality of agricultural products.

  9. Endoscopic Ultrasound-Guided Perirectal Abscess Drainage without Drainage Catheter: A Case Series

    Directory of Open Access Journals (Sweden)

    Eun Kwang Choi

    2017-05-01

    Full Text Available A perirectal abscess is a relatively common disease entity that occurs as a postsurgical complication or as a result of various medical conditions. Endoscopic ultrasound (EUS-guided drainage was recently described as a promising alternative treatment. Previous reports have recommended placement of a drainage catheter through the anus for irrigation, which is inconvenient to the patient and carries a risk of accidental dislodgement. We report four cases of perirectal abscess that were successfully treated with only one or two 7 F double pigtail plastic stent placements and without a drainage catheter for irrigation.

  10. THE DISTRIBUTION OF SOIL CHEMICAL PROPERTIES UNDER THE EFECT OF LAND RECLAMATION WORKS, FROM BAIA DRAINAGE SYSTEM

    Directory of Open Access Journals (Sweden)

    V. Moca

    2007-10-01

    Full Text Available In the pedo-climatic conditions of Suceava County that extends on a total surface of 855 300 ha, the balance of agricultural land affected by humidity excess with temporar or permanent character is differenciated from south to north and from east to west, between 30 % till 40%, which means almost 100 000 ha. On these soils with underground water or pluvial excess hydro ameliorative drainage systems have been installed, associated to a complex agroameliorative works. For long effect estimation of the underground drainage asociated with the agropedoameliorative works upon the some chemical properties, there were analyzed the soil and the environment conditions from Baia field.

  11. The Effect of Different Subsurface Drainage Systems on Improvement of Water Flow in Paddy fields

    Directory of Open Access Journals (Sweden)

    ghassem aghajani mazandarani

    2017-03-01

    Full Text Available Introduction: Better use of water and soil resources in paddy fields, increase in rice production and farmer's income, installation of subsurface drainage system is necessary. The main goalof these systems, are aeration conditions improvement prevention of water logging, yield increase, land use increase and multiuse of the land. In different countries, installation of subsurface drainage cause yield increase and working condition on the land, but no research has been conducted in different depths and spacing. On the other hand, spacing and depth are the most important parameters in the installation of drainage systems, have a direct effect on incoming water into the drains. The aim of this research, is an investigation of the effect of subsurface drainage with different depths and spacing on discharge rate variation and water table fall, in order to analyze the improvement of water flow movement in the soil. Also, study the effect of different drainage systems on the increase of the canola yield as the second cultivation in these treatments have been compared. Materials and Methods: To measure hydraulic conductivity in different depths, the auger holes have been dug (excavated. The saturated hydraulic conductivity in these holes wasdetermined using Ernst method (1950 before installation of drainage systems. In the drainage pilot plot of Sari Agricultural Sciences and Natural Resources University three subsurface drainage systems with mineral envelope have been installed. 1- The first one with the 0.9 m depth and 30 m spacing (D90 L30, 2- The second one with 0.65 m depth and 15 m spacing (D0.65 L15 and 3- The third one with 0.65 m depth and spacing (D0.65 L30 and one bi-level system with mineral envelope including four drains of 15 m spacing with 0.9 m and 0.65 m depths were installed alternatively. After auger hole equipment installations, in the middle spacing of two subsurface and water table reading possible, the water table fluctuation and

  12. Preoperative biliary drainage for pancreatic cancer

    NARCIS (Netherlands)

    van Heek, N. T.; Busch, O. R.; van Gulik, T. M.; Gouma, D. J.

    2014-01-01

    This review is to summarize the current knowledge about preoperative biliary drainage (PBD) in patients with biliary obstruction caused by pancreatic cancer. Most patients with pancreatic carcinoma (85%) will present with obstructive jaundice. The presence of toxic substances as bilirubin and bile

  13. Preoperative biliary drainage for pancreatic cancer.

    Science.gov (United States)

    Van Heek, N T; Busch, O R; Van Gulik, T M; Gouma, D J

    2014-04-01

    This review is to summarize the current knowledge about preoperative biliary drainage (PBD) in patients with biliary obstruction caused by pancreatic cancer. Most patients with pancreatic carcinoma (85%) will present with obstructive jaundice. The presence of toxic substances as bilirubin and bile salts, impaired liver function and altered nutritional status due to obstructive jaundice have been characterized as factors for development of complications after surgery. Whereas PBD was to yield beneficial effects in the experimental setting, conflicting results have been observed in clinical studies. The meta-analysis from relative older studies as well as more importantly a recent clinical trial showed that PBD should not be performed routinely. PBD for patients with a distal biliary obstruction is leading to more serious complications compared with early surgery. Arguments for PBD have shifted from a potential therapeutic benefit towards a logistic problem such as patients suffering from cholangitis and severe jaundice at admission or patients who need extra diagnostic tests, or delay in surgery due to a referral pattern or waiting list for surgery as well as candidates for neoadjuvant chemo(radio)therapy. If drainage is indicated in these patients it should be performed with a metal stent to reduce complications after the drainage procedure such as stent occlusion and cholangitis. Considering a change towards more neoadjuvant therapy regimes improvement of the quality of the biliary drainage concept is still important.

  14. Peritoneal drainage for newborn intestinal perforation: primary ...

    African Journals Online (AJOL)

    Keywords: intestinal perforation in newborn, necrotizing enterocolitis, primary peritoneal drainage. Department of Surgery, Paul L. Foster School of Medicine, Texas Tech University. HSC, El Paso, Texas, USA. Correspondence to Donald E. Meier, MD, Department of Surgery, Paul L. Foster. School of Medicine, Texas Tech ...

  15. Treatment of dyeing drainage by radiation

    International Nuclear Information System (INIS)

    Shimokawa, Toshinari; Sawai, Takeshi

    1985-01-01

    Decolorization of artificial dyeing drainage and sewage by radiation treatment. Artifical dyeing drainage was prepared from water, polyvinyl alcohol, starch, urea and several kinds of inorganic salts, and artificial sewage, from water, peptone, broth, urea and several kinds of inorganic salts. The above mentioned sample liquors of artificial dyeing drainage and sewage were exposed to γ-radiation of 5 kCi of 60 Co source by aerating through a ball filter. Absorption spectra, total organic carbon (TOC) and chemical oxygen demand (COD) were determined after irradiation to evaluate radiation treatment effect. With the experimental data obtained, it was clarified that absorbance, COD and TOC was decreased with the increase of absorbed dose. Decoloring was made effectively and about 95 % of bleaching ratio was obtained at 5 kGy of radiation. COD was decreased also by irradiation rather slower decreasing rate than that of decolorization, and TOC decrease was very slow at the initial stage of radiation but 40 % of TOC was decomposed by 10 kGy radiation. Dye of chemically stable structure was found more resistant to radiation decolorization. Decomposition efficiency was found less for dyes in the artificial sewage but secondary treated sewage showed no adverse effect. With the obtained understandings, a tentative scheme was planned for the radiation decolorization of dyeing drainage after aeration treatment. (Takagi, S.)

  16. GROUNDWATER IMPACTED BY ACID MINE DRAINAGE

    Science.gov (United States)

    The generation and release of acidic, metal-rich water from mine wastes continues to be an intractable environmental problem. Although the effects of acid mine drainage (AMD) are most evident in surface waters, there is an obvious need for developing cost-effective approaches fo...

  17. The Heimlich Valve for Pleural Cavity Drainage

    African Journals Online (AJOL)

    The ANNALS of AFRICAN SURGERY | www.annalsofafricansurgery.com. The ANNALS of AFRICAN SURGERY. July 2016 Volume 13 Issue 2 45. The Heimlich Valve for Pleural Cavity Drainage. Winston Ominde Makanga1, Andrew Nyaoncha Nyangau2 , Benjamin Njoga Njihia3. 1. St Mary's Mission Hospital, Elementaita.

  18. 1 The Effect of Camber Bed Drainage

    African Journals Online (AJOL)

    User

    The Effect of Camber Bed Drainage Landforms on Soil. Nutrient Distribution and Grain Yield of Maize on the Vertisols ... The Vertisols of the Accra Plains of Ghana are water logged after significant rainfall ... Excess application of 15-15-15 NPK and sulphate of ammonia fertilizers (150% .... beds, before planting and nutrient.

  19. Low-Resolution Modeling of Dense Drainage Networks in Confining Layers.

    Science.gov (United States)

    Pauw, P S; Van der Zee, S E A T M; Leijnse, A; Delsman, J R; De Louw, P G B; De Lange, W J; Oude Essink, G H P

    2015-01-01

    Groundwater-surface water (GW-SW) interaction in numerical groundwater flow models is generally simulated using a Cauchy boundary condition, which relates the flow between the surface water and the groundwater to the product of the head difference between the node and the surface water level, and a coefficient, often referred to as the "conductance." Previous studies have shown that in models with a low grid resolution, the resistance to GW-SW interaction below the surface water bed should often be accounted for in the parameterization of the conductance, in addition to the resistance across the surface water bed. Three conductance expressions that take this resistance into account were investigated: two that were presented by Mehl and Hill (2010) and the one that was presented by De Lange (1999). Their accuracy in low-resolution models regarding salt and water fluxes to a dense drainage network in a confined aquifer system was determined. For a wide range of hydrogeological conditions, the influence of (1) variable groundwater density; (2) vertical grid discretization; and (3) simulation of both ditches and tile drains in a single model cell was investigated. The results indicate that the conductance expression of De Lange (1999) should be used in similar hydrogeological conditions as considered in this paper, as it is better taking into account the resistance to flow below the surface water bed. For the cases that were considered, the influence of variable groundwater density and vertical grid discretization on the accuracy of the conductance expression of De Lange (1999) is small. © 2014, National GroundWater Association.

  20. Impact of tile drainage on evapotranspiration in South Dakota, USA, based on high spatiotemporal resolution evapotranspiration time series from a multi-satellite data fusion system

    Science.gov (United States)

    Yang, Yun; Anderson, Martha C.; Gao, Feng; Hain, Christopher; Kustas, William P.; Meyers, Tilden P.; Crow, Wade; Finocchiaro, Raymond G.; Otkin, Jason; Sun, Liang; Yang, Yang

    2017-01-01

    Soil drainage is a widely used agricultural practice in the midwest USA to remove excess soil water to potentially improve the crop yield. Research shows an increasing trend in baseflow and streamflow in the midwest over the last 60 years, which may be related to artificial drainage. Subsurface drainage (i.e., tile) in particular may have strongly contributed to the increase in these flows, because of its extensive use and recent gain in the popularity as a yield-enhancement practice. However, how evapotranspiration (ET) is impacted by tile drainage on a regional level is not well-documented. To explore spatial and temporal ET patterns and their relationship to tile drainage, we applied an energy balance-based multisensor data fusion method to estimate daily 30-m ET over an intensively tile-drained area in South Dakota, USA, from 2005 to 2013. Results suggest that tile drainage slightly decreases the annual cumulative ET, particularly during the early growing season. However, higher mid-season crop water use suppresses the extent of the decrease of the annual cumulative ET that might be anticipated from widespread drainage. The regional water balance analysis during the growing season demonstrates good closure, with the average residual from 2005 to 2012 as low as -3 mm. As an independent check of the simulated ET at the regional scale, the water balance analysis lends additional confidence to the study. The results of this study improve our understanding of the influence of agricultural drainage practices on regional ET, and can affect future decision making regarding tile drainage systems.

  1. 13 Morphometric Analysis of Ogunpa and Ogbere Drainage Basins ...

    African Journals Online (AJOL)

    `123456789jkl''''#

    form and process of drainage basins that may be widely ... ferruginous tropical soil on basement complex rock (Areola ... landuse pattern control the infiltration loss, the distribution of ... the water intercepted by Ogbere drainage basin to longer ...

  2. Estimating the benefits of improved drainage on pavement ...

    African Journals Online (AJOL)

    user

    2 Centre for Transportation Systems, Indian Institute of Technology Roorkee, INDIA ... parking lots that only allow cars, not trucks). ..... drainage section) and 2015 & 2019 (for poor drainage section) after the construction of an overlay, it was ...

  3. Internal drainage of infected pancreatic pseudocysts: safe or sorry?

    NARCIS (Netherlands)

    Boerma, D.; van Gulik, T. M.; Obertop, H.; Gouma, D. J.

    1999-01-01

    BACKGROUND: External drainage is the traditional surgical therapy for infected pancreatic pseudocyst, although associated with high morbidity and mortality rates. In this study it was determined whether internal drainage is feasible with acceptable postoperative morbidity and recurrence rates.

  4. Routine Sub-hepatic Drainage versus No Drainage after Laparoscopic Cholecystectomy: Open, Randomized, Clinical Trial.

    Science.gov (United States)

    Shamim, Muhammad

    2013-02-01

    Surgeons are still following the old habit of routine subhepatic drainage following laparoscopic cholecystectomy (LC). This study aims to compare the outcome of subhepatic drainage with no drainage after LC. This prospective study was conducted in two phases. Phase I was open, randomized controlled trial (RCT), conducted in Civil Hospital Karachi, from August 2004 to June 2005. Phase II was descriptive case series, conducted in author's practice hospitals of Karachi, from July 2005 to December 2009. In phase I, 170 patients with chronic calculous cholecystitis underwent LC. Patients were divided into two groups, subhepatic drainage (group A: 79 patients) or no drainage (group B: 76 patients). The rest 15 patients were excluded either due to conversion or elective subhepatic drainage. In phase II, 218 consecutive patients were enrolled, who underwent LC with no subhepatic drainage. Duration of operation, character, and amount of drain fluid (if placed), postoperative ultrasound for subhepatic collection, postoperative chest X-ray for the measurement of subdiaphragmatic air, postoperative pain, postoperative nausea/vomiting, duration of hospital stay, and preoperative or postoperative complications were noted and analyzed. Duration of operation and hospital stay was slightly longer in group A patients (P values 0.002 and 0.029, respectively); postoperative pain perception, nausea/vomiting, and postoperative complications were nearly same in both groups (P value 0.064, 0.078, and 0.003, respectively). Subhepatic fluid collection was more in group A (P = 0.002), whereas subdiaphragmatic air collection was more in group B (P = 0.003). Phase II results were nearly similar to group B patients in phase I. Routine subhepatic drainage after LC is not necessary in uncomplicated cases.

  5. Foamed emulsion drainage: flow and trapping of drops

    OpenAIRE

    Schneider, Maxime; Zou, Ziqiang; Langevin, Dominique; Salonen, Anniina

    2017-01-01

    Foamed emulsions are ubiquitous in our daily life but the ageing of such systems is still poorly understood. In this study we investigate foam drainage and measure the evolution of the gas, liquid and oil volume fractions inside the foam. We evidence three regimes of ageing. During an initial period of fast drainage, both bubbles and drops are very mobile. As the foam stabilises drainage proceeds leading to a gradual decrease of the liquid fraction and slowing down of drainage. Clusters of oi...

  6. Modes of supraglacial lake drainage and dynamic ice sheet response

    Science.gov (United States)

    Das, S. B.; Behn, M. D.; Joughin, I. R.

    2011-12-01

    We investigate modes of supraglacial lake drainage using geophysical, ground, and remote sensing observations over the western margin of the Greenland ice sheet. Lakes exhibit a characteristic life cycle defined by a pre-drainage, drainage, and post-drainage phase. In the pre-drainage phase winter snow fills pre-existing cracks and stream channels, efficiently blocking past drainage conduits. As temperatures increase in the spring, surface melting commences, initially saturating the snow pack and subsequently forming a surface network of streams that fills the lake basins. Basins continue to fill until lake drainage commences, which for individual lakes occurs at different times depending on the previous winter snow accumulation and summer temperatures. Three styles of drainage behavior have been observed: (1) no drainage, (2) slow drainage over the side into an adjacent pre-existing crack, and (3) rapid drainage through a new crack formed beneath the lake basin. Moreover, from year-to-year individual lakes exhibit different drainage behaviors. Lakes that drain slowly often utilize the same outflow channel for multiple years, creating dramatic canyons in the ice. Ultimately, these surface channels are advected out of the lake basin and a new channel forms. In the post-drainage phase, melt water continues to access the bed typically through a small conduit (e.g. moulin) formed near a local topographic minimum along the main drainage crack, draining the lake catchment throughout the remainder of the melt season. This melt water input to the bed leads to continued basal lubrication and enhanced ice flow compared to background velocities. Lakes that do not completely drain freeze over to form a surface ice layer that persists into the following year. Our results show that supraglacial lakes show a spectrum of drainage behaviors and that these styles of drainage lead to varying rates and timing of surface meltwater delivery to the bed resulting in different dynamic ice

  7. An update on the drainage of pyogenic lung abscesses

    Directory of Open Access Journals (Sweden)

    Siraj O Wali

    2012-01-01

    Full Text Available Most lung abscesses (80-90% are now successfully treated with antibiotics; however, this conservative approach may occasionally fail. When medical treatment fails, pulmonary resection is usually advised. Alternatively, percutaneous transthoracic tube drainage or endoscopic drainage can be considered, though both remain controversial. In this communication, the medical literature focusing on percutaneous tube drainage efficacy, indications, techniques, complications, and mortality, as well as available data regarding endoscopic drainage are reviewed.

  8. Land drainage and restoration of land after NCB opencast mining

    Energy Technology Data Exchange (ETDEWEB)

    Bragg, N.

    The author outlines the MAFF Field Drainage Research Unit's research into drainage of reinstated land. Current investigations have aimed at identifying the problems of reinstated soil and how they affect drainage design. Experiments on efficiency of permeable field drains and non-permeable field drains are mentioned. Further work is needed to examine long-term effects of storage on soil structure and whether existing drainage can be revitalised by secondary treatment.

  9. The foam drainage equation for drainage dynamics in unsaturated porous media

    Science.gov (United States)

    Lehmann, P.; Hoogland, F.; Assouline, S.; Or, D.

    2017-07-01

    Similarity in liquid-phase configuration and drainage dynamics of wet foam and gravity drainage from unsaturated porous media expands modeling capabilities for capillary flows and supplements the standard Richards equation representation. The governing equation for draining foam (or a soil variant termed the soil foam drainage equation—SFDE) obviates the need for macroscopic unsaturated hydraulic conductivity function by an explicit account of diminishing flow pathway sizes as the medium gradually drains. The study provides new and simple analytical expressions for drainage rates and volumes from unsaturated porous media subjected to different boundary conditions. Two novel analytical solutions for saturation profile evolution were derived and tested in good agreement with a numerical solution of the SFDE. The study and the proposed solutions rectify the original formulation of foam drainage dynamics of Or and Assouline (2013). The new framework broadens the scope of methods available for quantifying unsaturated flow in porous media, where the intrinsic conductivity and geometrical representation of capillary drainage could improve understanding of colloid and pathogen transport. The explicit geometrical interpretation of flow pathways underlying the hydraulic functions used by the Richards equation offers new insights that benefit both approaches.

  10. Water Drainage from Unsaturated Soils in a Centrifuge Permeameter

    Science.gov (United States)

    Ornelas, G.; McCartney, J.; Zhang, M.

    2013-12-01

    This study involves an analysis of water drainage from an initially saturated silt layer in a centrifuge permeameter to evaluate the hydraulic properties of the soil layer in unsaturated conditions up to the point where the water phase becomes discontinuous. These properties include the soil water retention curve (SWRC) and the hydraulic conductivity function (HCF). The hydraulic properties of unsaturated silt are used in soil-atmosphere interaction models that take into account the role of infiltration and evaporation of water from soils due to atmospheric interaction. These models are often applied in slope stability analyses, landfill cover design, aquifer recharge analyses, and agricultural engineering. The hydraulic properties are also relevant to recent research concerning geothermal heating and cooling, as they can be used to assess the insulating effects of soil around underground heat exchangers. This study employs a high-speed geotechnical centrifuge to increase the self-weight of a compacted silt specimen atop a filter plate. Under a centrifuge acceleration of N times earth's gravity, the concept of geometric similitude indicates that the water flow process in a small-scale soil layer will be similar to those in a soil layer in the field that is N times thicker. The centrifuge acceleration also results in an increase in the hydraulic gradient across the silt specimen, which causes water to flow out of the pores following Darcy's law. The drainage test was performed until the rate of liquid water flow out of the soil layer slowed to a negligible level, which corresponds to the transition point at which further water flow can only occur due to water vapor diffusion following Fick's law. The data from the drainage test in the centrifuge were used to determine the SWRC and HCF at different depths in the silt specimen, which compared well with similar properties defined using other laboratory tests. The transition point at which liquid water flow stopped (and

  11. Role of Lithology and Rock Structure in Drainage Development in ...

    African Journals Online (AJOL)

    Lithology and Rock structure play a vital role in the development of Drainage Network in any drainage basin. The drainage patterns upon land surface develop as directed by the underlying lithology and rock structure. In fact, lithology and rock structure together shape the basin and are decisive parameters of nature and ...

  12. Drainage of Splenic Abscess: A Case Report | Kombo | Nigerian ...

    African Journals Online (AJOL)

    ... and was managed by tube drainage. His post operative recovery was uneventful. Conclusion: Tube drainage of the splenic abscess is encouraged if there is easy access to the abscess and there is evidence of residual splenic tissue in the critically ill patient. Key Word: Tube drainage, splenic abscess, splenectomy.

  13. PASSIVE TREATMENT OF ACID ROCK DRAINAGE FROM A SUBSURFACE MINE

    Science.gov (United States)

    Acidic, metal-contaminated drainages are a critical problem facing many areas of the world. Acid rock drainage results when metal sulfide minerals, particularly pyrite, are oxidized by exposure to oxygen and water. The deleterious effects of these drainages on receiving streams a...

  14. 2011 Annual Industrial Wastewater Reuse Report for the Idaho National Laboratory Site's Materials and Fuels Complex Industrial Waste Ditch and Industrial Waste Pond

    Energy Technology Data Exchange (ETDEWEB)

    David Frederick

    2012-02-01

    This report describes conditions, as required by the state of Idaho Industrial Wastewater Reuse Permit (LA-000160-01), for the wastewater reuse site at the Idaho National Laboratory Site's Materials and Fuels Complex Industrial Waste Ditch and Industrial Waste Pond from November 1, 2010 through October 31, 2011. The report contains the following information: (1) Facility and system description; (2) Permit required effluent monitoring data and loading rates; (3) Groundwater monitoring data; (4) Status of special compliance conditions; and (5) Discussion of the facility's environmental impacts. During the 2011 reporting year, an estimated 6.99 million gallons of wastewater were discharged to the Industrial Waste Ditch and Pond which is well below the permit limit of 13 million gallons per year. Using the dissolved iron data, the concentrations of all permit-required analytes in the samples from the down gradient monitoring wells were below the Ground Water Quality Rule Primary and Secondary Constituent Standards.

  15. EFFECTIVENESS OF AUTOGENIC DRAINAGE VERSUS POSTURAL DRAINAGE ON OXYGEN SATURATION IN PATIENTS WITH CHRONIC BRONCHITIS WITH 15 MINUTES POST THERAPY

    OpenAIRE

    V. Kiran; Dr. Bhimasen .S; E. Mastanaiah; A. Thiruppathi

    2014-01-01

    Background: Patients with COPD will have more amount of secretions. To clear the secretions by using of different bronchial hygiene techniques like postural drainage and autogenic drainage technique, manual hyperventilation technique ,active cycle breathing technique .Hence in this study to compare the short-term effects of postural drainage with clapping (PD) and autogenic drainage (AD) on level of oxygen saturation in blood, and amount of sputum recovery. Methodology: The study was done ...

  16. BIODYNAMIC AGRICULTURE - ECO-FRIENDLY AGRICULTURAL PRACTICE

    Directory of Open Access Journals (Sweden)

    Veselka Vlahova

    2015-06-01

    Full Text Available Biodynamic agriculture is undoubtedly the oldest organized agricultural movement in the world. It is considered as an organic agricultural farming approach and determined as the oldest organized alternative agricultural movement in the world. In 1924 Rudolf Steiner – an Austrian natural scientist and philosopher, carried out a series of eight lectures in Koberwitz, currently Kobierzyce- Poland, where he formulated his visions on changes in agriculture and revealed his spiritual and scientific concepts about the connection between nature and agriculture by determining the important role of agriculture for the future of humanity and thus he became known as “the father of anthroposophy”. The great ecological effect of the application of the biodynamic agriculture is expressed in soil preservation and preservation of the living organisms in the soil, as well as maintenance of the natural balance in the vegetable and animal kingdom.

  17. Agrochemical mitigation of three aquatic macrophytes: implications for ecosystem services

    Science.gov (United States)

    Agricultural runoff containing nitrogen and phosphorus is a major contributor to eutrophication in aquatic systems. Vegetated drainage ditches lining agricultural fields have been investigated for their potential to mitigate runoff, acting similarly to a wetland as they filter contaminants. The ef...

  18. Assessment of aquifer properties, evapotranspiration, and the effects of ditching in the Stoney Brook watershed, Fond du Lac Reservation, Minnesota, 2006-9

    Science.gov (United States)

    Jones, Perry M.; Tomasek, Abigail A.

    2015-01-01

    The U.S. Geological Survey, in cooperation with the Fond du Lac Band of Lake Superior Chippewa, assessed hydraulic properties of geologic material, recharge, and evapotranspiration, and the effects of ditching on the groundwater resources in the Stoney Brook watershed in the Fond du Lac Reservation. Geologic, groundwater, and surface-water data were collected during 2006–9 to estimate hydrologic properties in the watershed. Streamflow and groundwater levels in the shallow glacial deposits in the Stoney Brook watershed were analyzed to estimate groundwater-flow directions, groundwater recharge, and evapotranspiration within the watershed and to assess the effect of ditches on surrounding groundwater resources. Groundwater, streamflow, and precipitation data collected during the study (2006–9) can be used to update the U.S. Department of Agriculture’s Natural Resource Conservation Service and Fond du Lac Resource Management Division surface-water models, which are used to evaluate the effect of proposed adjustments to the ditching system on streamflow on wild rice production and aquatic habitats.

  19. Reuse of drainage water in the Nile Delta; monitoring, modelling and analysis; final report Reuse of Drainage Water Project

    NARCIS (Netherlands)

    Staring Centrum, Instituut voor Onderzoek van het LandelijkGebied

    1995-01-01

    The effects of reusing drainage water have been evaluated and other options to increase the water utilization rate in Egypt explored. The results are an operational network for monitoring drainage water discharges and salinity along the major drains, a database for monitored drainage water

  20. Acid drainage from coal mining: Effect on paddy soil and productivity of rice.

    Science.gov (United States)

    Choudhury, Burhan U; Malang, Akbar; Webster, Richard; Mohapatra, Kamal P; Verma, Bibhash C; Kumar, Manoj; Das, Anup; Islam, Mokidul; Hazarika, Samarendra

    2017-04-01

    Overburden and acid drainage from coal mining is transforming productive agricultural lands to unproductive wasteland in some parts of Northeast India. We have investigated the adverse effects of acid mine drainage on the soil of rice paddy and productivity by comparing them with non-mined land and abandoned paddy fields of Jaintia Hills in Northeast India. Pot experiments with a local rice cultivar (Myngoi) as test crop evaluated biological productivity of the contaminated soil. Contamination from overburden and acid mine drainage acidified the soil by 0.5 pH units, increased the exchangeable Al 3+ content 2-fold and its saturation on clay complexes by 53%. Available sulfur and extractable heavy metals, namely Fe, Mn and Cu increased several-fold in excess of critical limits, while the availability of phosphorus, potassium and zinc contents diminished by 32-62%. The grain yield of rice was 62% less from fields contaminated with acid mine drainage than from fields that have not suffered. Similarly, the amounts of vegetation, i.e. shoots and roots, in pots filled with soil from fields that received acid mine drainage were 59-68% less than from uncontaminated land (average shoot weight: 7.9±2.12gpot -1 ; average root weight: 3.40±1.15gpot -1 ). Paddy fields recovered some of their productivity 4years after mining ceased. Step-wise multiple regression analysis affirmed that shoot weight in the pots and grain yield in field were significantly (p<0.01) and positively influenced by the soil's pH and its contents of K, N and Zn, while concentration of S in excess of threshold limits in contaminated soil significantly (p<0.01) reduced the weight of shoots in the pots and grain yield in the field. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Urban Agriculture Guide

    NARCIS (Netherlands)

    Visser, A.J.; Jansma, J.E.; Dekking, A.J.G.; Klieverik, M.J.M.

    2007-01-01

    The Urban Agriculture Guide describes the experiences, learning moments, tips and tricks of those involved in the initiatives of urban agriculture and an indication is provided of what is required to develop urban agriculture further in the Netherlands

  2. In-office drainage of sinus Mucoceles: An alternative to operating-room drainage.

    Science.gov (United States)

    Barrow, Emily M; DelGaudio, John M

    2015-05-01

    Endoscopic drainage has become the standard of care for the treatment of mucoceles. In many patients this can be performed in the office. This study reviews our experience with in-office endoscopic mucocele drainage. Retrospective chart review. A retrospective review of one surgeon's experience with in-office endoscopic drainage of sinus mucoceles between 2006 and 2014 was performed. Charts were reviewed for patient demographics, previous surgery, mucocele location, bone erosion, and outcomes. Thirty-two patients underwent 36 in-office drainage procedures. All procedures were performed under topical/local anesthesia. The mean age was 55 years (range, 17-92 years). The mean follow-up time was 444 days. Fifty-five percent had previous sinus surgery. The primary sinus involved was the frontal (12), anterior (11), posterior ethmoid (six), maxillary (four), and sphenoid (two). Bone erosion was noted to be present on computed tomography in 18 mucoceles (51%) (16 orbital, seven skull-base). All mucoceles were successfully accessed in the office with the exception of one, which was aborted due to neo-osteogenesis. Five patients (14% of mucoceles) required additional surgery, two for mucocele recurrence and three for septated mucoceles not completely drained in the office. No treatment complications occurred. All but one patient preferred in-office to operating-room drainage. In-office drainage of sinus mucoceles is well tolerated by patients, with high success and low complication rates, even in large mucoceles with bone erosion. The presence of septations and neo-osteogenesis reduce the likelihood of complete drainage and are relative contraindications. Orbital and skull base erosion are not contraindications. 4. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  3. Percutaneous drainage of chest abscesses in children

    International Nuclear Information System (INIS)

    Ball, W.S. Jr.; Towbin, R.B.; Bisset, G.S. III.

    1987-01-01

    Similar techniques for draining abdominal abscesses are now being applied to abscesses within the chest. This report describes the authors' experience in percutaneous drainage of seven chest abscesses in six children aged 3-13 years (mean, 7.3 years). Four pleural/extrapleural loculations were drained in three patients. Abscess location included right apex (one), right minor fissure (one), and left supradiaphragmatic (two). Collections resulted from esophageal perforation (two) or esophageal anastomotic leak (two). Three lung abscesses were drained in three patients. Abscess location included right lower, left lower, and right middle lobes. All lay adjacent to a pleural surface and were localized by CT or US before drainage. There were no complications. Complete resolution occurred in all six patients without the need for surgical intervention

  4. Range of drainage effect of surface mines

    Energy Technology Data Exchange (ETDEWEB)

    Sozanski, J.

    1978-03-01

    This paper discusses methods of calculating the range of effects of water drainage from surface coal mines and other surface mines. It is suggested that methods based on test pumping (water drainage) are time consuming, and the results can be distorted by atmospheric factors such as rain fall or dry period. So-called empirical formulae produce results which are often incorrect. The size of a cone shaped depression calculated on the basis of empirical formulae can be ten times smaller than the size of the real depression. It is suggested that using a formula based on the Dupuit formula is superior to other methods of depression calculation. According to the derived formulae the radius of the depresion cone is a function of parameters of the water bearing horizons, size of surface mine working and of water depression. The proposed formula also takes into account the influence of atmospheric factors (water influx caused by precipitation, etc.). (1 ref.) (In Polish)

  5. Percutaneous drainage of 100 subphrenic abscesses

    International Nuclear Information System (INIS)

    Casola, G.; Sonnenberg, E. van; D'Agostino, H.; Kothari, R.; May, S.; Taggart, S.

    1990-01-01

    PURPOSE: Percutaneous drainage of subphrenic abscesses is technically more difficult because lung and pleura may be transgressed during catheter insertion. The purpose of this paper is to determine the incidence of thoracic complications secondary to subphrenic abscess drainage and to determine factors that may alter this. The authors' series consists of 100 subphrenic abscesses that were drained percutaneously. Patients range in age from 14 to 75 years. Abscesses were secondary to surgery (splenectomy, pancreatectomy, partial hepatectomy, gastrectomy), pancreatitis, and trauma. Catheters ranged in size from 8 to 14 F and were inserted via trocar or Seldinger technique. Thoracic complications of pneumothorax or empyema were determined from follow-up chest radiographs or CT scans

  6. Agricultural SWOT analysis and wisdom agriculture design of chengdu

    Science.gov (United States)

    Zhang, Qian; Chen, Xiangyu; Du, Shaoming; Yin, Guowei; Yu, Feng; Liu, Guicai; Gong, Jin; Han, Fujun

    2017-08-01

    According to the status of agricultural information, this paper analyzed the advantages, opportunities and challenges of developing wisdom agriculture in Chengdu. By analyzed the local characteristics of Chengdu agriculture, the construction program of Chengdu wisdom agriculture was designed, which was based on the existing agricultural informatization. The positioning and development theme of Chengdu agriculture is leisure agriculture, urban agriculture and quality agriculture.

  7. Drainage and Stratification Kinetics of Foam Films

    Science.gov (United States)

    Zhang, Yiran; Sharma, Vivek

    2014-03-01

    Baking bread, brewing cappuccino, pouring beer, washing dishes, shaving, shampooing, whipping eggs and blowing bubbles all involve creation of aqueous foam films. Foam lifetime, drainage kinetics and stability are strongly influenced by surfactant type (ionic vs non-ionic), and added proteins, particles or polymers modify typical responses. The rate at which fluid drains out from a foam film, i.e. drainage kinetics, is determined in the last stages primarily by molecular interactions and capillarity. Interestingly, for certain low molecular weight surfactants, colloids and polyelectrolyte-surfactant mixtures, a layered ordering of molecules, micelles or particles inside the foam films leads to a stepwise thinning phenomena called stratification. Though stratification is observed in many confined systems including foam films containing particles or polyelectrolytes, films containing globular proteins seem not to show this behavior. Using a Scheludko-type cell, we experimentally study the drainage and stratification kinetics of horizontal foam films formed by protein-surfactant mixtures, and carefully determine how the presence of proteins influences the hydrodynamics and thermodynamics of foam films.

  8. Performance evaluation of a full-scale advanced phase isolation ditch process by using real-time control strategies

    International Nuclear Information System (INIS)

    Kim, Hyosoo; Kim, Yejin; Kim, Minsoo; Piao, Wenhua; Kim, Changwon; Gee, Jeasung

    2014-01-01

    This paper proposes real-time control strategies that can be applied in a full-scale advanced phase isolation ditch (APID) process. Real-time operation mode control (OMC) and aeration section control (ASC) strategies were developed to cope more stably with fluctuations in the influent loading and to increase the nitrification and denitrification reactions within the entire volume. The real-time OMC and ASC strategies were evaluated using mathematical models. When the NH 4 -N in the reactor was maintained at a high level, appropriate control actions, such as continuing the aeration state, stopping the influent inflow and increasing the aeration section, were applied in the APID process. In contrast, when the NO X -N in the reactor was maintained at a high level, the non-aeration state, influent inflow, and decreased aeration section were continued. It was concluded that stable operation in the APID process could be achieved by applying real-time OMC and ASC strategies developed in this study

  9. Performance evaluation of a full-scale advanced phase isolation ditch process by using real-time control strategies

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyosoo; Kim, Yejin; Kim, Minsoo; Piao, Wenhua; Kim, Changwon [Pusan National University, Busan (Korea, Republic of); Gee, Jeasung [Taiwha Industrial Co. Ltd., Seoul (Korea, Republic of)

    2014-04-15

    This paper proposes real-time control strategies that can be applied in a full-scale advanced phase isolation ditch (APID) process. Real-time operation mode control (OMC) and aeration section control (ASC) strategies were developed to cope more stably with fluctuations in the influent loading and to increase the nitrification and denitrification reactions within the entire volume. The real-time OMC and ASC strategies were evaluated using mathematical models. When the NH{sub 4}-N in the reactor was maintained at a high level, appropriate control actions, such as continuing the aeration state, stopping the influent inflow and increasing the aeration section, were applied in the APID process. In contrast, when the NO{sub X}-N in the reactor was maintained at a high level, the non-aeration state, influent inflow, and decreased aeration section were continued. It was concluded that stable operation in the APID process could be achieved by applying real-time OMC and ASC strategies developed in this study.

  10. Agriculture land use and environmental issues

    International Nuclear Information System (INIS)

    Khan, S.M.L

    2005-01-01

    There is agro-pastoral farming system prevalent in mountainous and sub-mountainous areas of Himalayan region including Azad Jammu and Kashmir. As such, Agriculture Sector includes Crop-husbandry, livestock farming and forestry in its ambit. There are varied forms of land uses, like crop farming, forestry, animal husbandry, fisheries, wildlife conservation etc. Therefore, the paper attempts to spotlight the interplay of these land uses with respect to the environment in general with specific reference to AJK and other mountainous and sub- mountainous regions of Northern Pakistan. Agricultural activities have both negative and beneficial effects on the environment. The negative effects in the forms of physical degradation of the soil due to agriculture are: soil erosion, desertification, water logging and salinity and soil compaction. The land use practices such as overgrazing, deforestation and some cultivation practices, removal of vegetative cover or hedgerows, lack of proper drainage outlets, accentuate these problems. The improper management of water use and sometimes excessive mechanization and Ploughing further aggravates problem of physical degradation of the soil. The chemical degradation, as a result of agricultural practices, include acidification, Salinization, contamination caused by pesticides and insecticides and resultantly water and air pollution, and loss of habitats and biodiversity. Further negative effects emerging out of agricultural practices are greenhouse gas emissions, nutrient losses and lowering of humus content, which makes soil susceptible to compaction and erosion. The beneficial environmental effects emanating from the use of best agricultural management practices and integrated farming systems are protection of soil fertility and stability, prevention of excessive run offs. It also provides habitats for varied forms of flora and fauna, reduce the emission of carbon dioxide (CO/sub 2)/ and reduce the incidence and severity of natural

  11. Acid drainage (AD) in nature and environmental impact of acid mine drainage (AMD) in Southern Tuscany

    International Nuclear Information System (INIS)

    Di Lella, Luigi Antonello; Protano, Giuseppe; Riccobono, Francesco

    2005-01-01

    Acid drainage (AD) is a natural process occurring locally at the Earth's surface. It consists in a substantial increase of acidity of surface waters as a result of chemical reactions occurring in the atmosphere (i.e. acid rain) or involving reactive phases (i.e. pyrite) present in the percolated medium. Acidic surface waters (usually pH < 4) can be produced by oxidation of sulphides (mainly pyrite and other iron sulphides) exposed to atmospheric oxygen, while human activities, such as mining, can greatly enhance this process. Acid drainage promoted by mining activities is called acid mine drainage (AMD) and is a primary source of environmental pollution and a world-wide problem in both active and abandoned mining areas. In fact, exposure of iron sulphides to oxidising conditions produces strongly acidic drainage waters rich in sulphate and a variety of heavy elements (i.e. As, Cd, Pb, Sb). Several occurrences of active acid mine drainage have been found in the Metalliferous Hills (southern Tuscany). The most important AMD phenomena were observed in the Fenice Capanne and Niccioleta mining areas

  12. Long term dynamics of nitrate concentrations and leaching losses in tile drainage water from cultivated clayey till at field scale

    DEFF Research Database (Denmark)

    Ernstsen, Vibeke; Olsen, Preben; Rosenbom, Annette Elisabeth

    2014-01-01

    of application). Furthermore, the standard climatic conditions (e.g. temperature, precipitation) as well as soil moisture and temperature to a depth of approx. 2 meter were measured. Concentrations of nitrate in the drainage and groundwater, recharge of water through the drainage system as well as depth......Since 1985, several political agreements have been adopted to protect the aquatic environment and nature in Denmark. The farmers have repeatedly been ordered to reduce the consumption of nitrogen in their agricultural production. The reductions have been imposed nation-wide regardless of e.......g. climate, soil type and local hydraulic conditions. By the end of 2013, the Danish Commission of Nature and Agriculture issued a report which recommend that for the future protection of surface nitrogen regulations should be locally adapted, and if possible, at the level of field scale. This kind...

  13. Comparison between autologous blood transfusion drainage and closed-suction drainage/no drainage in total knee arthroplasty: a meta-analysis.

    Science.gov (United States)

    Hong, Kun-Hao; Pan, Jian-Ke; Yang, Wei-Yi; Luo, Ming-Hui; Xu, Shu-Chai; Liu, Jun

    2016-08-01

    Autologous blood transfusion (ABT) drainage system is a new unwashed salvaged blood retransfusion system for total knee replacement (TKA). However, whether to use ABT drainage, closed-suction (CS) drainage or no drainage in TKA surgery remains controversial. This is the first meta-analysis to assess the clinical efficiency, safety and potential advantages regarding the use of ABT drains compared with closed-suction/no drainage. PubMed, Embase, and the Cochrane Library were comprehensively searched in March 2015. Fifteen randomized controlled trials (RCTs) were identified and pooled for statistical analysis. The primary outcome evaluated was homologous blood transfusion rate. The secondary outcomes were post-operative haemoglobin on days 3-5, length of hospital stay and wound infections after TKA surgery. The pooled data included 1,721 patients and showed that patients in the ABT drainage group might benefit from lower blood transfusion rates (16.59 % and 37.47 %, OR: 0.28 [0.14, 0.55]; 13.05 % and 16.91 %, OR: 0.73 [0.47,1.13], respectively). Autologous blood transfusion drainage and closed-suction drainage/no drainage have similar clinical efficacy and safety with regard to post-operative haemoglobin on days 3-5, length of hospital stay and wound infections. Autologous blood transfusion drainage offers a safe and efficient alternative to CS/no drainage with a lower blood transfusion rate. Future large-volume high-quality RCTs with extensive follow-up will affirm and update this system review.

  14. Fluoroscopy guided percutaneous catheter drainage of pneumothorax in good mid-term patency with tube drainage

    International Nuclear Information System (INIS)

    Park, Ga Young; Oh, Joo Hyung; Yoon, Yup; Sung, Dong Wook

    1995-01-01

    To evaluate efficacy and the safety of percutaneous catheter drainage in patients with pneumothorax that is difficult to treat with closed thoracotomy. We retrospectively reviewed effectiveness of percutaneous catheter drainage (PCD) in 10 patients with pneumothorax. The catheter was inserted under fluoroscopic guidance. Seven patients had spontaneous pneumothorax caused by tuberculosis (n =4), reptured bullae (n = 2), and histiocytosis-X (n = 1). Three patients had iatrogenic pneumothorax caused by trauma (n = 1) and surgery (n = 2). All procedures were performed by modified Seldinger's method by using 8F-20F catheter. All catheter were inserted successfully. In 9 of 10 patients, the procedure was curative without further therapy. Duration of catheter insertion ranged from 1 day to 26 days. In the remaining 1 patient in whom multiple pneumothorax occurred after operation, catheter insertion was performed twice. Percutaneous catheter drainage under fluoroscopic guidance is effective and safe procedure for treatment of pneumothorax in patients with failed closed thoracotomy

  15. Fluoroscopy guided percutaneous catheter drainage of pneumothorax in good mid-term patency with tube drainage

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ga Young; Oh, Joo Hyung; Yoon, Yup; Sung, Dong Wook [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1995-10-15

    To evaluate efficacy and the safety of percutaneous catheter drainage in patients with pneumothorax that is difficult to treat with closed thoracotomy. We retrospectively reviewed effectiveness of percutaneous catheter drainage (PCD) in 10 patients with pneumothorax. The catheter was inserted under fluoroscopic guidance. Seven patients had spontaneous pneumothorax caused by tuberculosis (n =4), reptured bullae (n = 2), and histiocytosis-X (n = 1). Three patients had iatrogenic pneumothorax caused by trauma (n = 1) and surgery (n = 2). All procedures were performed by modified Seldinger's method by using 8F-20F catheter. All catheter were inserted successfully. In 9 of 10 patients, the procedure was curative without further therapy. Duration of catheter insertion ranged from 1 day to 26 days. In the remaining 1 patient in whom multiple pneumothorax occurred after operation, catheter insertion was performed twice. Percutaneous catheter drainage under fluoroscopic guidance is effective and safe procedure for treatment of pneumothorax in patients with failed closed thoracotomy.

  16. Weather, landscape, and management effects on nitrate and soluble phosphorus concentrations in subsurface drainage discharge in the western Lake Erie basin

    Science.gov (United States)

    Subsurface drainage, while an important and necessary agricultural production practice in the Midwest, contributes nitrate (NO3) and soluble phosphorus (P) to surface waters. Eutrophication (i.e., excessive enrichment of waters by NO3 and soluble P) supports harmful algal blooms (HABs) in receiving ...

  17. Field-scale monitoring of the long-term impact and sustainability of drainage water reuse on the west side of California’s San Joaquin Valley

    Science.gov (United States)

    Diminishing freshwater resources have brought attention to the reuse of degraded water as a potential water resource rather than as a disposal problem. Drainage water from tile-drained, irrigated agricultural land is degraded water that is often in large supply, but the long-term impact and sustain...

  18. Field-scale monitoring of the long-term impact and sustainability of drainage water reuse using ECa-directed soil sampling

    Science.gov (United States)

    Diminishing freshwater resources have brought attention to the reuse of degraded water as a water resource rather than a disposal problem. Drainage water from tile-drained, irrigated agricultural land is degraded water that is often in large supply, but the long-term impact and sustainability of it...

  19. Vocational Agriculture Computer Handbook.

    Science.gov (United States)

    Kentucky State Dept. of Education, Frankfort.

    This document is a catalog of reviews of computer software suitable for use in vocational agriculture programs. The reviews were made by vocational agriculture teachers in Kentucky. The reviews cover software on the following topics: farm management, crop production, livestock production, horticulture, agricultural mechanics, general agriculture,…

  20. Experimental and numerical analysis of the drainage of aluminium foams

    International Nuclear Information System (INIS)

    Brunke, O; Hamann, A; Cox, S J; Odenbach, S

    2005-01-01

    Drainage is one of the driving forces for the temporal instability of molten metal foams. For usual aqueous foams this phenomenon is well examined and understood on both the experimental and the theoretical side. The situation is different for metallic foams. Due to their opaque nature, the observation of drainage is only possible by either measuring the density distribution of solidified samples ex situ or by x-ray or neutron radioscopy. Up to now there exists just one theoretical study describing the drainage behaviour of metallic foams incorporating the drainage equation, the temperature dependence of the viscosity and thermal transport. This paper will present results on the drainage behaviour of aluminium foams grown by a powder-metallurgical production route. For this purpose an experiment which allows the observation of drainage in cylindrical metal foam columns has been developed. Experimental density profiles after different drainage times are measured ex situ and compared to numerical results of the standard drainage equation for aqueous foams. This first comparison between the density redistribution of metallic aluminium foams and numerical solutions shows that the standard drainage equation can be used to explain the drainage behaviour of metallic foams

  1. Traditional Foley drainage systems--do they drain the bladder?

    Science.gov (United States)

    Garcia, Maurice M; Gulati, Shelly; Liepmann, Dorian; Stackhouse, G Bennett; Greene, Kirsten; Stoller, Marshall L

    2007-01-01

    Foley catheters are assumed to drain the bladder to completion. Drainage characteristics of Foley catheter systems are poorly understood. To investigate unrecognized retained urine with Foley catheter drainage systems, bladder volumes of hospitalized patients were measured with bladder scan ultrasound volumetrics. Additionally, an in vitro bench top mock bladder and urinary catheter system was developed to understand the etiology of such residual volumes. A novel drainage tube design that optimizes indwelling catheter drainage was also designed. Bedside bladder ultrasound volumetric studies were performed on patients hospitalized in ward and intensive care unit. If residual urine was identified the drainage tubing was manipulated to facilitate drainage. An ex vivo bladder-urinary catheter model was designed to measure flow rates and pressures within the drainage tubing of a traditional and a novel drainage tube system. A total of 75 patients in the intensive care unit underwent bladder ultrasound volumetrics. Mean residual volume was 96 ml (range 4 to 290). In 75 patients on the hospital ward mean residual volume was 136 ml (range 22 to 647). In the experimental model we found that for every 1 cm in curl height, obstruction pressure increased by 1 cm H2O within the artificial bladder. In contrast, the novel spiral-shaped drainage tube demonstrated rapid (0.5 cc per second), continuous and complete (100%) reservoir drainage in all trials. Traditional Foley catheter drainage systems evacuate the bladder suboptimally. Outflow obstruction is caused by air-locks that develop within curled redundant drainage tubing segments. The novel drainage tubing design eliminates gravity dependent curls and associated air-locks, optimizes flow, and minimizes residual bladder urine.

  2. [Theories and methodologies of engineering designs on sustainable agricultural land consolidation project--a case study of Xuemeiyang land consolidation project in Changtai County, Fujian Province].

    Science.gov (United States)

    Ye, Yanmei; Wu, Cifang; Cheng, Chengbiao; Qiu, Lingzhang; Huang, Shengyu; Zheng, Ruihui

    2002-09-01

    The concept and characteristics of engineering designs on sustainable agricultural land consolidation project were discussed in this paper. Principles, basic methods and procedures of engineering designs on agricultural land consolidation project were put forward, which were successfully adopted for designing agricultural land consolidation in Xuemeiyang region of Changtai County, including diversity designs of sustainable land use, engineering designs of soil improvement, roads, ditches, and drains for protecting existent animal environments, and design of ecological shelter-forests in farmland. Moreover, from sustainable economic, ecological and social points, the results of these engineering designs were evaluated based on fouteen important indexes. After carrying out these engineeringdesigns, the eco-environments and agricultural production conditions were significantly improved, and the farm income was increased in planned regions.

  3. Gender in crop agriculture

    OpenAIRE

    Food and Agriculture Organization; The World Bank; IFAD

    2008-01-01

    Metadata only record This is a module in the "Gender in Agriculture Sourcebook" published by the World Bank, UN Food and Agriculture Organization, and International Fund for Agricultural Development. This module examines the role of gender in crop agriculture as an essential component of development and poverty reduction. Gender is an integral aspect of crop agriculture because women's roles in crop production and household subsistence, as well as their knowledge of complex production syst...

  4. Button self-retaining drainage catheter

    International Nuclear Information System (INIS)

    Caridi, James G.; Hawkins, Irvin F.; Akins, E. William; Young, Ronald S.

    1997-01-01

    To help improve patient acceptance of long-term internal/external catheter access to the biliary tract in those with benign biliary obstruction, a simple design allows the catheter end to remain flush with the skin. It consists of a clothes button affixed to the drainage catheter with a wood screw after the catheter has been cut off at the skin exit. This button/screw device has been used successfully in 22 patients over the last 10 years; catheter exchanges were easily accomplished

  5. Percutaneous biliary drainage in patients with cholangiocarcinoma

    International Nuclear Information System (INIS)

    Mehta, A.C.; Gobel, R.J.; Rose, S.C.; Hayes, J.K.; Miller, F.J.

    1990-01-01

    This paper determines whether radiation therapy (RT) is a risk factor for infectious complications (particularly hepatic abscess formation) related to percutaneous biliary drainage (PBD). The authors retrospectively reviewed the charts of 98 consecutive patients who had undergone PBD for obstruction. In 34 patients with benign obstruction, three infectious complications occurred, none of which were hepatic abscess or fatal sepsis. In 39 patients who had malignant obstruction but did not have cholangiocarcinoma, 13 infectious complications occurred, including two hepatic abscesses and three cases of fatal sepsis. Of the 25 patients with cholangiocarcinoma, 15 underwent RT; in these 15 patients, 14 infectious complications occurred, including six hepatic abscesses and two cases of fatal sepsis

  6. Radiologic drainage of infected and noninfected thoracic fluid collections

    International Nuclear Information System (INIS)

    Van Sonnenberg, E.; Casola, G.; Stavas, J.; Neff, C.C.; Varney, R.A.; Wittich, G.R.; Dillard, J.; Christensen, R.A.; Friedman, P.J.

    1987-01-01

    Radiologically guided drainage of 100 thoracic fluid collections is described in this paper. Collections that underwent drainage include empyemas, lung abscesses, bronchopleural fistulas (BPFs), mediastinal abscesses, paracardial collections, bronchogenic cysts, sequestrations, lymphoceles, lymphangiomas, malignant effusions, and necrotic tumors. Catheters were placed for sclerotherapy in nine patients. Guidance modalities (in descending order of frequency) were CT, US, fluoroscopy, and MR. Inadequate thoracostomy tube drainage occurred in a third of the patients prior to radiologic drainage. Drainages were effective in 85% of cases, sparing surgery or another thoracostomy tube. Complications occurred in 7% of patients, most being minor and none requiring operation. Criteria for drainage of lung abscess and BPF will be emphasized, as will techniques and methods of follow-up

  7. Percutaneous drainage of diverticular abscess: Adjunct to resection

    International Nuclear Information System (INIS)

    Mueller, P.R.; Saini, S.; Butch, R.J.; Simeone, J.F.; Rodkey, G.V.; Bousquet, J.C.; Ottinger, L.W.; Wittenberg, J.; Ferrucci, J.T. Jr.

    1986-01-01

    Traditional surgical management of acute diverticulitis with abscess may require a one-, two-, or three-stage procedure. Because of recent interest in CT diagnosis of diverticulitis, and novel access routes for interventional drainage of deep pelvic abscesses, the authors investigated the potential for converting complex two- and three-stage surgical procedures to simpler, safer one-stage colon resections by percutaneous drainage of the associated abscess. Of 23 patients with acute perforated diverticulitis who were referred for catheter drainage under radiologic guidance, successful catheter drainage and subsequent single-stage colon resection were carried out in 15. In three patients catheter drainage was unsuccessful and a multistage procedure was required. In three patients only percutaneous drainage was performed and operative intervention was omitted entirely

  8. Nitrogen-removal performance and community structure of nitrifying bacteria under different aeration modes in an oxidation ditch.

    Science.gov (United States)

    Guo, Chang-Zi; Fu, Wei; Chen, Xue-Mei; Peng, Dang-Cong; Jin, Peng-Kang

    2013-07-01

    Oxidation-ditch operation modes were simulated using sequencing batch reactors (SBRs) with alternate stirring and aerating. The nitrogen-removal efficiencies and nitrifying characteristics of two aeration modes, point aeration and step aeration, were investigated. Under the same air-supply capacity, oxygen dissolved more efficiently in the system with point aeration, forming a larger aerobic zone. The nitrifying effects were similar in point aeration and step aeration, where the average removal efficiencies of NH4(+) N were 98% and 96%, respectively. When the proportion of anoxic and oxic zones was 1, the average removal efficiencies of total nitrogen (TN) were 45% and 66% under point aeration and step aeration, respectively. Step aeration was more beneficial to both anoxic denitrification and simultaneous nitrification and denitrification (SND). The maximum specific ammonia-uptake rates (AUR) of point aeration and step aeration were 4.7 and 4.9 mg NH4(+)/(gMLVSS h), respectively, while the maximum specific nitrite-uptake rates (NUR) of the two systems were 7.4 and 5.3 mg NO2(-)-N/(gMLVSS h), respectively. The proportions of ammonia-oxidizing bacteria (AOB) to all bacteria were 5.1% under point aeration and 7.0% under step aeration, and the proportions of nitrite-oxidizing bacteria (NOB) reached 6.5% and 9.0% under point and step aeration, respectively. The dominant genera of AOB and NOB were Nitrosococcus and Nitrospira, which accounted for 90% and 91%, respectively, under point aeration, and the diversity of nitrifying bacteria was lower than under step aeration. Point aeration was selective of nitrifying bacteria. The abundance of NOB was greater than that of AOB in both of the operation modes, and complete transformation of NH4(+) N to NO3(-)-N was observed without NO2(-)-N accumulation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Recycled water reuse permit renewal application for the materials and fuels complex industrial waste ditch and industrial waste pond

    Energy Technology Data Exchange (ETDEWEB)

    Name, No

    2014-10-01

    This renewal application for the Industrial Wastewater Reuse Permit (IWRP) WRU-I-0160-01 at Idaho National Laboratory (INL), Materials and Fuels Complex (MFC) Industrial Waste Ditch (IWD) and Industrial Waste Pond (IWP) is being submitted to the State of Idaho, Department of Environmental Quality (DEQ). This application has been prepared in compliance with the requirements in IDAPA 58.01.17, Recycled Water Rules. Information in this application is consistent with the IDAPA 58.01.17 rules, pre-application meeting, and the Guidance for Reclamation and Reuse of Municipal and Industrial Wastewater (September 2007). This application is being submitted using much of the same information contained in the initial permit application, submitted in 2007, and modification, in 2012. There have been no significant changes to the information and operations covered in the existing IWRP. Summary of the monitoring results and operation activity that has occurred since the issuance of the WRP has been included. MFC has operated the IWP and IWD as regulated wastewater land treatment facilities in compliance with the IDAPA 58.01.17 regulations and the IWRP. Industrial wastewater, consisting primarily of continuous discharges of nonhazardous, nonradioactive, routinely discharged noncontact cooling water and steam condensate, periodic discharges of industrial wastewater from the MFC facility process holdup tanks, and precipitation runoff, are discharged to the IWP and IWD system from various MFC facilities. Wastewater goes to the IWP and IWD with a permitted annual flow of up to 17 million gallons/year. All requirements of the IWRP are being met. The Operations and Maintenance Manual for the Industrial Wastewater System will be updated to include any new requirements.

  10. Preoperative biliary drainage for periampullary tumors causing obstructive jaundice; DRainage vs. (direct) OPeration (DROP-trial)

    NARCIS (Netherlands)

    N.A. van der Gaag (Niels); S.M.M. de Castro (Steve); E.A.J. Rauws (Erik); M.J. Bruno (Marco); C.H.J. van Eijck (Casper); E.J. Kuipers (Ernst); J.J.G.M. Gerritsen (Josephus); J.P. Rutten (Joost Paul); J.W. Greve; E.J. Hesselink (Eric); J.H. Klinkenbijl (Jean); I.H.M.B. Rinkes; D. Boerma (Djamila); B.A. Bonsing (Bert); C.J. van Laarhoven (Cees); F.J. Kubben; E. van der Harst (Erwin); M.N. Sosef (Meindert); K. Bosscha (Koop); I.H.J.T. de Hingh (Ignace); L. Th de Wit (Laurens); O.M. van Delden (Otto); O.R.C. Busch (Olivier); T.M. van Gulik (Thomas); P.M.M. Bossuyt (Patrick); D.J. Gouma (Dirk)

    2007-01-01

    textabstractBackground. Surgery in patients with obstructive jaundice caused by a periampullary (pancreas, papilla, distal bile duct) tumor is associated with a higher risk of postoperative complications than in non-jaundiced patients. Preoperative biliary drainage was introduced in an attempt to

  11. Preoperative biliary drainage for periampullary tumors causing obstructive jaundice; DRainage vs. (direct) OPeration (DROP-trial)

    NARCIS (Netherlands)

    van der Gaag, Niels A.; de Castro, Steve M. M.; Rauws, Erik A. J.; Bruno, Marco J.; van Eijck, Casper H. J.; Kuipers, Ernst J.; Gerritsen, Josephus J. G. M.; Rutten, Jan-Paul; Greve, Jan Willem; Hesselink, Erik J.; Klinkenbijl, Jean H. G.; Borel Rinkes, Inne H. M.; Boerma, Djamila; Bonsing, Bert A.; van Laarhoven, Cees J.; Kubben, Frank J. G. M.; van der Harst, Erwin; Sosef, Meindert N.; Bosscha, Koop; de Hingh, Ignace H. J. T.; Th de Wit, Laurens; van Delden, Otto M.; Busch, Olivier R. C.; van Gulik, Thomas M.; Bossuyt, Patrick M. M.; Gouma, Dirk J.

    2007-01-01

    BACKGROUND: Surgery in patients with obstructive jaundice caused by a periampullary (pancreas, papilla, distal bile duct) tumor is associated with a higher risk of postoperative complications than in non-jaundiced patients. Preoperative biliary drainage was introduced in an attempt to improve the

  12. Arterial Pulsations cannot Drive Intramural Periarterial Drainage: Significance for Aβ Drainage

    Directory of Open Access Journals (Sweden)

    Alexandra K. Diem

    2017-08-01

    Full Text Available Alzheimer's Disease (AD is the most common form of dementia and to date there is no cure or efficient prophylaxis. The cognitive decline correlates with the accumulation of amyloid-β (Aβ in the walls of capillaries and arteries. Our group has demonstrated that interstitial fluid and Aβ are eliminated from the brain along the basement membranes of capillaries and arteries, the intramural periarterial drainage (IPAD pathway. With advancing age and arteriosclerosis, the stiffness of arterial walls, this pathway fails in its function and Aβ accumulates in the walls of arteries. In this study we tested the hypothesis that arterial pulsations drive IPAD and that a valve mechanism ensures the net drainage in a direction opposite to that of the blood flow. This hypothesis was tested using a mathematical model of the drainage mechanism. We demonstrate firstly that arterial pulsations are not strong enough to produce drainage velocities comparable to experimental observations. Secondly, we demonstrate that a valve mechanism such as directional permeability of the IPAD pathway is necessary to achieve a net reverse flow. The mathematical simulation results are confirmed by assessing the pattern of IPAD in mice using pulse modulators, showing no significant alteration of IPAD. Our results indicate that forces other than the cardiac pulsations are responsible for efficient IPAD.

  13. Reuse of drainage water model : calculation method of drainage water and watertable depth

    NARCIS (Netherlands)

    Roest, C.W.J.; Rijtema, P.E.; Abdel Khalik, M.A.

    1986-01-01

    The main objective of the project is to assist the Ministry of Irrigation in Egypt in the planning of future watermanagement strategies incorporating reuse of drainage water practices. In order to achieve this main objective a comprehensive measurement programme has been initiated and a mathematical

  14. Time effects of water drainage from deposited back-fill

    International Nuclear Information System (INIS)

    Baranski, L.A.

    1976-01-01

    Time effects of water drainage from deposited back-fill in mine excavations are considered. The time dependence of drainage from the deposited material was determined from ''in situ'' measurements with the aid of radioisotope gauges. The measurements were performed for given drainage conditions and practically constant grain size composition. It was found that in a few hours after the end of the back-filling operation the mechanical properties of the deposited material are practically constant. (author)

  15. Pancreatic tissue fluid pressure during drainage operations for chronic pancreatitis

    DEFF Research Database (Denmark)

    Ebbehøj, N; Borly, L; Madsen, P

    1990-01-01

    Pancreatic tissue fluid pressure was measured in 10 patients undergoing drainage operations for painful chronic pancreatitis. The pressure was measured by the needle technique in the three anatomic regions of the pancreas before and at different stages of the drainage procedure, and the results...... a decrease in pancreatic tissue fluid pressure during drainage operations for pain in chronic pancreatitis. Regional pressure decrease were apparently unrelated to ERCP findings....

  16. Effect of viscosity on tear drainage and ocular residence time.

    Science.gov (United States)

    Zhu, Heng; Chauhan, Anuj

    2008-08-01

    An increase in residence time of dry eye medications including artificial tears will likely enhance therapeutic benefits. The drainage rates and the residence time of eye drops depend on the viscosity of the instilled fluids. However, a quantitative understanding of the dependence of drainage rates and the residence time on viscosity is lacking. The current study aims to develop a mathematical model for the drainage of Newtonian fluids and also for power-law non-Newtonian fluids of different viscosities. This study is an extension of our previous study on the mathematical model of tear drainage. The tear drainage model is modified to describe the drainage of Newtonian fluids with viscosities higher than the tear viscosity and power-law non-Newtonian fluids with rheological parameters obtained from fitting experimental data in literature. The drainage rate through canaliculi was derived from the modified drainage model and was incorporated into a tear mass balance to calculate the transients of total solute quantity in ocular fluids and the bioavailability of instilled drugs. For Newtonian fluids, increasing the viscosity does not affect the drainage rate unless the viscosity exceeds a critical value of about 4.4 cp. The viscosity has a maximum impact on drainage rate around a value of about 100 cp. The trends are similar for shear thinning power law fluids. The transients of total solute quantity, and the residence time agrees at least qualitatively with experimental studies. A mathematical model has been developed for the drainage of Newtonian fluids and power-law fluids through canaliculi. The model can quantitatively explain different experimental observations on the effect of viscosity on the residence of instilled fluids on the ocular surface. The current study is helpful for understanding the mechanism of fluid drainage from the ocular surface and for improving the design of dry eye treatments.

  17. Modeling of subglacial hydrological development following rapid supraglacial lake drainage

    OpenAIRE

    Dow, C F; Kulessa, B; Rutt, I C; Tsai, V C; Pimentel, S; Doyle, S H; van As, D; Lindb?ck, K; Pettersson, R; Jones, G A; Hubbard, A

    2015-01-01

    The rapid drainage of supraglacial lakes injects substantial volumes of water to the bed of the Greenland ice sheet over short timescales. The effect of these water pulses on the development of basal hydrological systems is largely unknown. To address this, we develop a lake drainage model incorporating both (1) a subglacial radial flux element driven by elastic hydraulic jacking and (2) downstream drainage through a linked channelized and distributed system. Here we present the model and exa...

  18. Pancreatic tissue fluid pressure during drainage operations for chronic pancreatitis

    DEFF Research Database (Denmark)

    Ebbehøj, N; Borly, L; Madsen, P

    1990-01-01

    Pancreatic tissue fluid pressure was measured in 10 patients undergoing drainage operations for painful chronic pancreatitis. The pressure was measured by the needle technique in the three anatomic regions of the pancreas before and at different stages of the drainage procedure, and the results...... were compared with preoperative endoscopic retrograde cholangiopancreatography (ERCP) morphology. The preoperatively elevated pressure decreased in all patients but one, to normal or slightly elevated values. The median pressure decrease was 50% (range, 0-90%; p = 0.01). The drainage anastomosis (a...... a decrease in pancreatic tissue fluid pressure during drainage operations for pain in chronic pancreatitis. Regional pressure decrease were apparently unrelated to ERCP findings....

  19. Development of laundry drainage treatment system with ceramic ultra filter

    International Nuclear Information System (INIS)

    Kanda, Masanori; Kurahasi, Takafumi

    1995-01-01

    A compact laundry drainage treatment system (UF system hereafter) with a ceramic ultra filter membrane (UF membrane hereafter) has been developed to reduce radioactivity in laundry drainage from nuclear power plants. The UF membrane is made of sintered fine ceramic. The UF membrane has 0.01 μm fine pores, resulting in a durable, heat-resistant, and corrosion-resistant porous ceramic filter medium. A cross-flow system, laundry drainage is filtrated while it flows across the UF membrane, is used as the filtration method. This method creates less caking when compared to other methods. The UF membrane is back washed at regular intervals with permeated water to minimize caking of the filter. The UF membrane and cross-flow system provides long stable filtration. The ceramic UF membrane is strong enough to concentrate suspended solids in laundry drainage up to a weight concentration of 10%. The final concentrated laundry drainage can be treated in an incinerator. The performance of the UF system was checked using radioactive laundry drainage. The decontamination factor of the UF system was 25 or more. The laundry drainage treatment capacity and concentration ratio of the UF system, as well as the service life of the UF membrane were also checked by examination using simulated non-radioactive laundry drainage. Even though laundry drainage was concentrated 1000 times, the UF system showed good permeated water quality and permeated water flux. (author)

  20. The construction technology of Chinese ancient city drainage facilities

    Science.gov (United States)

    Hequn, Li; Yufengyun

    2018-03-01

    In ancient china, according to the local natural environment, a variety of drainage facilities were built in order to excrete rainwater, domestic sewage, production wastewater and so on. These drainage facilities were mainly made of pottery, bricks, wood, stone, etc. For example, ceramic water pipelines, buried in the ground, connect together one by one, and there was a slight drop from one end to the other in favor of drainage. These measures can also be used for reference in today’s urban drainage and flood control.

  1. Technology and Economic Assessment of Innovative Field Drainage Technologies in Denmark

    DEFF Research Database (Denmark)

    Gachango, Florence Gathoni

    Intensive agricultural production in most parts of the world especially in the more developed countries continues to mount pressure on water resources thereby threatening the quality of life in the aquatic ecosystems. With stringent standards such as those stipulated in the European Union Water...... Framework Directive (EU WFD), introduced to address the water quality problem the situation calls for solutions that would reconcile these two conflicting issues. “End-of-pipe” filter technologies that would disconnect agricultural drainage pathway before it gets to the aquatic environment have been...... proposed as appropriate solutions to this problem in the Danish context. The feasibility of these technologies with regards to their cost-effectiveness in nutrient mitigation, farmers’ adoption behavior, and environmental policy implementation is assessed in this thesis. The thesis comprises of four papers...

  2. Agricultural policy schemes

    DEFF Research Database (Denmark)

    Hansen, Henning Otte

    2016-01-01

    Agricultural support is a very important element in agricultural policy in many countries. Agricultural support is basically an instrument to meet the overall objectives of the agricultural policy – objectives set by society. There are a great number of instruments and ways of intervention...... in agricultural policy and they have different functions and impacts. Market price support and deficiency payments are two very important instruments in agricultural policy; however, they belong to two different support regimes or support systems. Market price support operates in the so-called high price system...

  3. Fractionation, transfer, and ecological risks of heavy metals in riparian and ditch wetlands across a 100-year chronosequence of reclamation in an estuary of China

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Rong [State Key Laboratory of Water Environment Stimulation, School of Environment, Beijing Normal University, Beijing 100875 (China); School of Nature Conservation, Beijing Forestry University, Beijing 100083 (China); Bai, Junhong, E-mail: junhongbai@163.com [State Key Laboratory of Water Environment Stimulation, School of Environment, Beijing Normal University, Beijing 100875 (China); Lu, Qiongqiong; Zhao, Qingqing; Gao, Zhaoqin; Wen, Xiaojun; Liu, Xinhui [State Key Laboratory of Water Environment Stimulation, School of Environment, Beijing Normal University, Beijing 100875 (China)

    2015-06-01

    The effect of reclamation on heavy metal concentrations and the ecological risks in ditch wetlands (DWs) and riparian wetlands (RWs) across a 100-year chronosequence in the Pearl River Estuary of China was investigated. Concentrations of 4 heavy metals (Cd, Cu, Pb, and Zn) in soil and plant samples, and sequential extracts of soil samples were determined, using inductively coupled plasma atomic absorption spectrometry. Results showed that heavy metal concentrations were higher in older DW soils than in the younger ones, and that the younger RW soils contained higher heavy metal concentrations compared to the older ones. Although the increasing tendency of heavy metal concentrations in soil was obvious after wetland reclamation, the metals Cu, Pb, and Zn exhibited low or no risks to the environment based on the risk assessment code (RAC). Cd, on the other hand, posed a medium or high risk. Cd, Pb, and Zn were mainly bound to Fe–Mn oxide, whereas most of Cu remained in the residual phase in both ditch and riparian wetland soils, and the residual proportions generally increased with depth. Bioconcentration and translocation factors for most of these four heavy metals significantly decreased in the DWs with older age (p < 0.05), whereas they increased in the RWs with younger age (p < 0.05). The DW soils contained higher concentrations of heavy metals in the organic fractions, whereas there were more carbonate and residual fractions in the RW soils. The non-bioavailable fractions of Cu and Zn, and the organic-bound Cd and Pb significantly inhibited plant growth. - Highlights: • Heavy metals in ditch wetland accumulated with increasing reclamation history. • Heavy metals exist in the Fe–Mn oxides and residual fractions in both wetlands. • Cd posed a medium to high environmental risk while low risk for other metals. • Long reclamation history caused lower BCFs and TFs in DWs and higher levels in RWs. • RW soils contained more heavy metals in the carbonate

  4. Fractionation, transfer, and ecological risks of heavy metals in riparian and ditch wetlands across a 100-year chronosequence of reclamation in an estuary of China

    International Nuclear Information System (INIS)

    Xiao, Rong; Bai, Junhong; Lu, Qiongqiong; Zhao, Qingqing; Gao, Zhaoqin; Wen, Xiaojun; Liu, Xinhui

    2015-01-01

    The effect of reclamation on heavy metal concentrations and the ecological risks in ditch wetlands (DWs) and riparian wetlands (RWs) across a 100-year chronosequence in the Pearl River Estuary of China was investigated. Concentrations of 4 heavy metals (Cd, Cu, Pb, and Zn) in soil and plant samples, and sequential extracts of soil samples were determined, using inductively coupled plasma atomic absorption spectrometry. Results showed that heavy metal concentrations were higher in older DW soils than in the younger ones, and that the younger RW soils contained higher heavy metal concentrations compared to the older ones. Although the increasing tendency of heavy metal concentrations in soil was obvious after wetland reclamation, the metals Cu, Pb, and Zn exhibited low or no risks to the environment based on the risk assessment code (RAC). Cd, on the other hand, posed a medium or high risk. Cd, Pb, and Zn were mainly bound to Fe–Mn oxide, whereas most of Cu remained in the residual phase in both ditch and riparian wetland soils, and the residual proportions generally increased with depth. Bioconcentration and translocation factors for most of these four heavy metals significantly decreased in the DWs with older age (p < 0.05), whereas they increased in the RWs with younger age (p < 0.05). The DW soils contained higher concentrations of heavy metals in the organic fractions, whereas there were more carbonate and residual fractions in the RW soils. The non-bioavailable fractions of Cu and Zn, and the organic-bound Cd and Pb significantly inhibited plant growth. - Highlights: • Heavy metals in ditch wetland accumulated with increasing reclamation history. • Heavy metals exist in the Fe–Mn oxides and residual fractions in both wetlands. • Cd posed a medium to high environmental risk while low risk for other metals. • Long reclamation history caused lower BCFs and TFs in DWs and higher levels in RWs. • RW soils contained more heavy metals in the carbonate

  5. Contributions of systematic tile drainage to watershed-scale phosphorus transport.

    Science.gov (United States)

    King, Kevin W; Williams, Mark R; Fausey, Norman R

    2015-03-01

    Phosphorus (P) transport from agricultural fields continues to be a focal point for addressing harmful algal blooms and nuisance algae in freshwater systems throughout the world. In humid, poorly drained regions, attention has turned to P delivery through subsurface tile drainage. However, research on the contributions of tile drainage to watershed-scale P losses is limited. The objective of this study was to evaluate long-term P movement through tile drainage and its manifestation at the watershed outlet. Discharge data and associated P concentrations were collected for 8 yr (2005-2012) from six tile drains and from the watershed outlet of a headwater watershed within the Upper Big Walnut Creek watershed in central Ohio. Results showed that tile drainage accounted for 47% of the discharge, 48% of the dissolved P, and 40% of the total P exported from the watershed. Average annual total P loss from the watershed was 0.98 kg ha, and annual total P loss from the six tile drains was 0.48 kg ha. Phosphorus loads in tile and watershed discharge tended to be greater in the winter, spring, and fall, whereas P concentrations were greatest in the summer. Over the 8-yr study, P transported in tile drains represented 90% of all measured concentrations exceeded recommended levels (0.03 mg L) for minimizing harmful algal blooms and nuisance algae. Thus, the results of this study show that in systematically tile-drained headwater watersheds, the amount of P delivered to surface waters via tile drains cannot be dismissed. Given the amount of P loss relative to typical application rates, development and implementation of best management practices (BMPs) must jointly consider economic and environmental benefits. Specifically, implementation of BMPs should focus on late fall, winter, and early spring seasons when most P loading occurs. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  6. Inventory of drainage wells and potential sources of contaminants to drainage-well inflow in Southwest Orlando, Orange County, Florida

    Science.gov (United States)

    Taylor, George Fred

    1993-01-01

    Potential sources of contaminants that could pose a threat to drainage-well inflow and to water in the Floridan aquifer system in southwest Orlando, Florida, were studied between October and December 1990. Drainage wells and public-supply wells were inventoried in a 14-square-mile area, and available data on land use and activities within each drainage well basin were tabulated. Three public-supply wells (tapping the Lower Floridan aquifer) and 38 drainage wells (open to the Upper Floridan aquifer) were located in 17 drainage basins within the study area. The primary sources of drainage-well inflow are lake overflow, street runoff, seepage from the surficial aquifer system, and process-wastewater disposal. Drainage-well inflow from a variety of ares, including resi- dential, commercial, undeveloped, paved, and industrial areas, are potential sources of con- taminants. The four general types of possible contaminants to drainage-well inflow are inorganic chemicals, organic compounds, turbidity, and microbiological contaminants. Potential contami- nant sources include plant nurseries, citrus groves, parking lots, plating companies, auto- motive repair shops, and most commonly, lake- overflow water. Drainage wells provide a pathway for contaminants to enter the Upper Floridan aquifer and there is a potential for contaminants to move downward from the Upper Floridan to the Lower Floridan aquifer.

  7. Eco policy: Environmental Stress and Conflicts in Africa. Case Study of Drainage Basins

    International Nuclear Information System (INIS)

    Okidi, C.O

    1994-01-01

    The main cause for African misery is limited supply of water which has a direct impact on agricultural production. The continent of Africa has a reticulation of 54 drainage basins including rivers which either traverse boundaries or form part of such boundaries. These basins cover approximately half of the continent but only 2% of the total water is utilized leaving 98% to replenish the oceans. In future Africa should focus attention on control, apportionment and utilization of the waters of it's drainage basins in order to ameliorate the the problems brought about by scarcity of rainfall and consequent drought and famine. After the drought in the late 1970s and mid-1980s, there has been efforts to control the promising rivers and transfer the water to to centres of agriculture and human settlements and this is likely to cause international conflicts. The author recommends that, in order to control such conflicts the basin states there should be systematic collaboration among the basin states in the management of such waters

  8. Design and Hydrologic Performance of a Tile Drainage Treatment Wetland in Minnesota, USA

    Directory of Open Access Journals (Sweden)

    Christian Lenhart

    2016-11-01

    Full Text Available Treatment wetlands are increasingly needed to remove nitrate from agricultural drainage water to protect downstream waters, such as the Gulf of Mexico. This project sought to develop a new edge-of-field treatment wetland, designed to remove nitrate-nitrogen and enhance phosphorus removal by plant harvest and to monitor its effectiveness. A 0.10 ha wetland was designed and installed to treat subsurface drainage flow from farmland in southwestern Minnesota, USA, in 2013, and monitored for three years by recording flow, nitrate-nitrogen, total phosphorus (TP and soluble orthophosphorus (OP input to and output from the wetland. Prior to construction, a level-pool routing, mass balance approach with DRAINMOD flow inputs was used to predict nitrate removal efficiency. Nitrate load removal averaged 68% over three years, nearly matching model predictions. However, most denitrification occurred in the sub-soil of the wetland rather than in surface flow as predicted. Phosphorus removal was approximately 76% over three years, and phosphorus removed by plant uptake exceeded inflow mass in the third year. The edge-of-field design has potential as a cost-effective method to treat field outflows because agricultural landowners can adopt this treatment system with minimal loss of productive farmland. The wet-prairie vegetation and shallow depth also provide the opportunity to remove additional phosphorus via vegetative harvest.

  9. Tile drainage as karst: Conduit flow and diffuse flow in a tile-drained watershed

    Science.gov (United States)

    Schilling, K.E.; Helmers, M.

    2008-01-01

    The similarity of tiled-drained watersheds to karst drainage basins can be used to improve understanding of watershed-scale nutrient losses from subsurface tile drainage networks. In this study, short-term variations in discharge and chemistry were examined from a tile outlet collecting subsurface tile flow from a 963 ha agricultural watershed. Study objectives were to apply analytical techniques from karst springs to tile discharge to evaluate water sources and estimate the loads of agricultural pollutants discharged from the tile with conduit, intermediate and diffuse flow regimes. A two-member mixing model using nitrate, chloride and specific conductance was used to distinguish rainwater versus groundwater inputs. Results indicated that groundwater comprised 75% of the discharge for a three-day storm period and rainwater was primarily concentrated during the hydrograph peak. A contrasting pattern of solute concentrations and export loads was observed in tile flow. During base flow periods, tile flow consisted of diffuse flow from groundwater sources and contained elevated levels of nitrate, chloride and specific conductance. During storm events, suspended solids and pollutants adhered to soil surfaces (phosphorus, ammonium and organic nitrogen) were concentrated and discharged during the rapid, conduit flow portion of the hydrograph. During a three-day period, conduit flow occurred for 5.6% of the time but accounted for 16.5% of the total flow. Nitrate and chloride were delivered primarily with diffuse flow (more than 70%), whereas 80-94% of total suspended sediment, phosphorus and ammonium were exported with conduit and intermediate flow regimes. Understanding the water sources contributing to tile drainage and the manner by which pollutant discharge occurs from these systems (conduit, intermediate or diffuse flow) may be useful for designing, implementing and evaluating non-point source reduction strategies in tile-drained landscapes. ?? 2007 Elsevier B.V. All

  10. Endoscopic ultrasound-guided transmural drainage of postoperative pancreatic collections.

    Science.gov (United States)

    Tilara, Amy; Gerdes, Hans; Allen, Peter; Jarnagin, William; Kingham, Peter; Fong, Yuman; DeMatteo, Ronald; D'Angelica, Michael; Schattner, Mark

    2014-01-01

    Pancreatic leak is a major cause of morbidity after pancreatectomy. Traditionally, peripancreatic fluid collections have been managed by percutaneous or operative drainage. Data for endoscopic ultrasound (EUS)-guided drainage of postoperative fluid collections are limited. Here we report on the safety, efficacy, and timing of EUS-guided drainage of postoperative peripancreatic collections. This is a retrospective review of 31 patients who underwent EUS-guided drainage of fluid collections after pancreatic resection. Technical success was defined as successful transgastric deployment of at least one double pigtail plastic stent. Clinical success was defined as resolution of the fluid collection on follow-up CT scan and resolution of symptoms. Early drainage was defined as initial transmural stent placement within 30 days after surgery. Endoscopic ultrasound-guided drainage was performed effectively with a technical success rate of 100%. Clinical success was achieved in 29 of 31 patients (93%). Nineteen of the 29 patients (65%) had complete resolution of their symptoms and collection with the first endoscopic procedure. Repeat drainage procedures, including some with necrosectomy, were required in the remaining 10 patients, with eventual resolution of collection and symptoms. Two patients who did not achieve durable clinical success required percutaneous drainage by interventional radiology. Seventeen (55%) of 31 patients had successful early drainage completed within 30 days of their operation. Endoscopic ultrasound-guided drainage of fluid collections after pancreatic resection is safe and effective. Early drainage (collections was not associated with increased complications in this series. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  11. Agriculture: Land Use

    Science.gov (United States)

    Land Use and agriculture. Information about land use restrictions and incentive programs.Agricultural operations sometimes involve activities regulated by laws designed to protect water supplies, threatened or endangered plants and animals, or wetlands.

  12. Agricultural Health and Safety

    Science.gov (United States)

    ... that occur while living, working, or visiting agricultural work environments (primarily farms) are considered agricultural injuries, whether or ... of Labor's Occupational Safety & Health Administration (OSHA) supports safe and healthful working conditions by setting and enforcing standards and by ...

  13. Innovations in urban agriculture

    NARCIS (Netherlands)

    Schans, van der J.W.; Renting, Henk; Veenhuizen, Van René

    2014-01-01

    This issuehighlights innovations in urban agriculture. Innovation and the various forms of innovations are of particular importance because urban agriculture is adapted to specific urban challenges and opportunities. Innovation is taking place continuously, exploring the multiple fundions of urban

  14. Agricultural Research Service

    Science.gov (United States)

    ... Menu United States Department of Agriculture Agricultural Research Service Research Research Home National Programs Research Projects Scientific Manuscripts International Programs Scientific Software/Models Databases and Datasets Office of Scientific Quality ...

  15. Agricultural science policy

    OpenAIRE

    Alston, Julian M.; Pardey, Philip G.; Taylor, Michael J.

    2001-01-01

    Technological advances developed through R&D have supplied the world with not only more food, but better food. This report looks at issues raised by this changing environment for agricultural productivity, agricultural R&D, and natural resource management.

  16. Technical Analysis of In-Valley Drainage Management Strategies for the Western San Joaquin Valley, California

    Science.gov (United States)

    Presser, Theresa S.; Schwarzbach, Steven E.

    2008-01-01

    The western San Joaquin Valley is one of the most productive farming areas in the United States, but salt-buildup in soils and shallow groundwater aquifers threatens this area?s productivity. Elevated selenium concentrations in soils and groundwater complicate drainage management and salt disposal. In this document, we evaluate constraints on drainage management and implications of various approaches to management considered in: *the San Luis Drainage Feature Re-Evaluation (SLDFRE) Environmental Impact Statement (EIS) (about 5,000 pages of documentation, including supporting technical reports and appendices); *recent conceptual plans put forward by the San Luis Unit (SLU) contractors (i.e., the SLU Plans) (about 6 pages of documentation); *approaches recommended by the San Joaquin Valley Drainage Program (SJVDP) (1990a); and *other U.S. Geological Survey (USGS) models and analysis relevant to the western San Joaquin Valley. The alternatives developed in the SLDFRE EIS and other recently proposed drainage plans (refer to appendix A for details) differ from the strategies proposed by the San Joaquin Valley Drainage Program (1990a). The Bureau of Reclamation (USBR) in March 2007 signed a record of decision for an in-valley disposal option that would retire 194,000 acres of land, build 1,900 acres of evaporation ponds, and develop a treatment system to remove salt and selenium from drainwater. The recently proposed SLU Plans emphasize pumping drainage to the surface, storing approximately 33% in agricultural water re-use areas, treating selenium through biotechnology, enhancing the evaporation of water to concentrate salt, and identifying ultimate storage facilities for the remaining approximately 67% of waste selenium and salt. The treatment sequence of reuse, reverse osmosis, selenium bio-treatment, and enhanced solar evaporation is unprecedented and untested at the scale needed to meet plan requirements. All drainage management strategies that have been proposed

  17. Gender and agricultural markets

    OpenAIRE

    Food and Agriculture Organization; The World Bank; IFAD

    2008-01-01

    Metadata only record This is a module in the "Gender in Agriculture Sourcebook" published by the World Bank, UN Food and Agriculture Organization, and International Fund for Agricultural Development. This module examines the traditional division of labor within agricultural markets, where women farmers are primarily responsible for subsistence and household crop production while male farmers dominate the commercial sector. Challenging these gendered roles by increasing women farmers' acces...

  18. Benthic algae of benchmark streams in agricultural areas of eastern Wisconsin

    Science.gov (United States)

    Scudder, Barbara C.; Stewart, Jana S.

    2001-01-01

    Benthic algae were collected from 20 streams in the Western Lake Michigan Drainages by the U.S. Geological Survey in May and June of 1993 as part of the National Water-Quality Assessment program. These streams were selected to represent "benchmark" streams that were minimally affected by human activities, especially agriculture, for comparison to other streams in similar environmental settings. Streams were chosen from four relatively homogeneous units (RHU's) in agricultural areas with differing texture of surficial deposits and bedrock type.

  19. Division of Agriculture

    Science.gov (United States)

    Department of Natural Resources logo, color scheme Department of Natural Resources Division of Agriculture Search Search DNR's site DNR State of Alaska Toggle main menu visibility Agriculture Home Programs Asset Disposals Alaska Caps Progam Board of Agriculture & Conservation Farm To School Program Grants

  20. Gender in Agriculture Sourcebook

    OpenAIRE

    World Bank; Food and Agriculture Organization; International Fund for Agricultural Development

    2009-01-01

    Three out of every four poor people in developing countries live in rural areas, and most of them depend directly or indirectly on agriculture for their livelihoods. In many parts of the world, women are the main farmers or producers, but their roles remain largely unrecognized. The 2008 World development report: agriculture for development highlights the vital role of agriculture in susta...

  1. Nigeria Agricultural Journal: Submissions

    African Journals Online (AJOL)

    Author Guidelines. NATURE OF PAPERS. Papers should be of agricultural interest and include: full reports of original research not previously elsewhere, research notes which consist of brief or new findings; techniques and equipment of importance to agricultural workers; evaluations of problems and trends in agricultural ...

  2. Biotechnology and Agriculture.

    Science.gov (United States)

    Kenney, Martin

    Even at this early date in the application of biotechnology to agriculture, it is clear that agriculture may provide the largest market for new or less expensive biotechnologically manufactured products. The chemical and pharmaceutical industries that hold important positions in agricultural inputs are consolidating their positions by purchasing…

  3. Arterial Complications of Percutaneous Transhepatic Biliary Drainage

    International Nuclear Information System (INIS)

    L'Hermine, Claude; Ernst, Olivier; Delemazure, Olivier; Sergent, Geraldine

    1996-01-01

    Purpose: To report on the frequency and treatment of arterial complications due to percutaneous transhepatic biliary drainage (PTBD).Materials: Lesions of the intrahepatic artery were encountered in 10 of 525 patients treated by PTBD (2%). Hemobilia followed in 9 patients and subcapsular hematoma in 1. Seven patients had a benign biliary stenosis and 3 had a malignant stenosis.Results: The bleeding resolved spontaneously in 3 patients. In 7 it required arterial embolization, which was successfully achieved either through the percutaneous catheter (n= 3) or by arteriography (n= 4).Conclusion: Arterial bleeding is a relatively rare complication of PTBD that can easily be treated by selective arterial embolization when it does not resolve spontaneously. In this series its frequency was much higher (16%) when the stenosis was benign than when it was malignant (0.6%)

  4. Nasolacrimal drainage system cyst in an adult.

    Science.gov (United States)

    Yamasoba, T; Sugimura, H

    1996-01-01

    A cyst of the nasolacrimal drainage system (NLDS) is rare in an adult. We report a case in a 29-year-old man of a mucous retention cyst of the NLDS, which appeared 2 years after the patient developed dacryocystitis coincident with an aggravation of chronic sinusitis. The lesion was successfully managed by removing the bony wall of the NLDS at the interface with the ethmoid and nasal cavity, as well as the membranous closure of the ostium of the common canaliculus. We speculate that the cyst development might have been initiated by inflammatory change such as mucosal adhesion in the NLDS resulting from the spread of secondary infection from the sinonasal tract.

  5. Drainage treatment technology for water pollution prevention

    Energy Technology Data Exchange (ETDEWEB)

    Ebise, Sen' ichi

    1988-03-01

    Drainage is purified either at terminal treatment plants or by septic tanks for sewage. At terminal treatment plants, sewage is purified by activated sludge prosessing or by biological treatment equipment. By the normal activated sludge processing, only 20 - 30 % of nitrogen and phosphur can be removed. To solve this problem, many advanced processing systems have been employed, representative systems being coagulating sedimentation, rapid filtration, recirculating nitro-denitrification, etc. The coagulating sedimentation is a treatment process in which such metallic salt coagulations as aluminum, iron, etc. are injected and mixed with sewage, and then phosphur and the like are sedimented in the form of grains. The rapid filtration requires no large space, and can reliably remove suspended matter. For large scale septic tank processing system, advance treatment processing is supplemented to improve the quality of treated water. Among other systems of sewage purification are oxidized channel, oxidized pond, soil treatment, etc. (2 figs, 2 refs)

  6. Integrated urban drainage, status and perspectives

    DEFF Research Database (Denmark)

    Harremoës, Poul

    2002-01-01

    This paper summarises the status of urban storm drainage as an integrated professional discipline, including the management-policy interface, by which the goals of society are implemented. The paper assesses the development of the discipline since the INTERURBA conference in 1992 and includes...... aspects of the papers presented at the INTERURBA-II conference in 2001 and the discussions during the conference. Tools for integrated analysis have been developed, but there is less implementation than could be expected. That is due to lack of adequate knowledge about important mechanisms, coupled...... with a significant conservatism in the business. However, significant integrated analyses have been reported. Most of them deal with the sewer system and the treatment plant, while few incorporate the receiving water as anything but the object of the loads to be minimised by engineering measures up-stream. Important...

  7. 13 Morphometric Analysis of Ogunpa and Ogbere Drainage Basins ...

    African Journals Online (AJOL)

    `123456789jkl''''#

    significance of these landscape parameters was ... reported that the geomorphic characteristics of a drainage basins play ... form and process of drainage basins that may ... tropical rain forest of Nigeria occupying an area of .... morphometric parameters such as relief, shape ... on floodplains can be pulled down while areas.

  8. Natural attenuation of antimony in mine drainage water

    International Nuclear Information System (INIS)

    Manaka, Mitsuo; Yanase, Nobuyuki; Sato, Tsutomu; Fukushi, Keisuke

    2007-01-01

    In this study, we investigated the natural attenuation of antimony (Sb) in the drainage water of an abandoned mine. Drainage water, waste rocks, and ocherous precipitates collected from the mine were investigated in terms of their mineralogy and chemistry. The chemistry of the drainage water was analyzed by measuring pH, oxidation-reduction potential (ORP), and electric conductivity on site as well as by inductively coupled plasma mass spectrometry and ion chromatography. As the drainage flowed downstream, the pH decreased rapidly from 7.05 to 3.26 and then increased slowly to 3.50. In a section where the pH increased, ocherous precipitates occur on a drainage water channel. We determined Sb levels in the drainage water, and the distribution of Sb in the mineral phases of waste rocks and precipitates was estimated by means of a sequential extraction procedure. The results of these investigations indicated that Sb, which is generated by the dissolution of stibnite (Sb 2 S 3 ) and secondary formed Sb minerals in waste rocks, was attenuated by iron-bearing ocherous precipitates, especially schwertmannite, that form over time in the drainage water. The Sb concentrations in the ocherous precipitates were up to 370 mg/kg, whereas the Sb concentrations in the drainage water downstream were below background levels (0.6 μg/L). Bulk distribution coefficients (K d ) for this Sb adsorption to the precipitates ranges up to at least 10 5 L/kg. (author)

  9. Predictors of chest drainage complications in trauma patients

    Directory of Open Access Journals (Sweden)

    CECÍLIA ARAÚJO MENDES

    2018-04-01

    Full Text Available ABSTRACT Objective: to identify predictors of chest drainage complications in trauma patients attended at a University Hospital. Methods: we conducted a retrospective study of 68 patients submitted to thoracic drainage after trauma, in a one-year period. We analyzed gender, age, trauma mechanism, trauma indices, thoracic and associated lesions, environment in which the procedure was performed, drainage time, experience of the performer, complications and evolution. Results: the mean age of the patients was 35 years and the male gender was the most prevalent (89%. Blunt trauma was the most frequent, with 67% of cases, and of these, 50% were due to traffic accidents. The mean TRISS (Trauma and Injury Severity Score was 98, with a mortality rate of 1.4%. The most frequent thoracic and associated lesions were, respectively, rib fractures (51% and abdominal trauma (32%. The mean drainage time was 6.93 days, being higher in patients under mechanical ventilation (p=0.0163. The complication rate was 26.5%, mainly poor drain positioning (11.77%. Hospital drainage was performed in 89% of cases by doctors in the first year of specialization. Thoracic drainage performed in prehospital care presented nine times more chances of complications (p=0.0015. Conclusion: the predictors of post-trauma complications for chest drainage were a procedure performed in an adverse site and mechanical ventilation. The high rate of complications demonstrates the importance of protocols of care with the thoracic drainage.

  10. Coupling between drainage and coarsening in wet foam

    Indian Academy of Sciences (India)

    Abstract. Drainage and coarsening are two coupled phenomena during the evolution of wet foam. We show the variation in the growth rate of bubble size, along the height in a column of Gillette shaving foam, by microscope imaging. Simultaneously, the drainage of liquid at the same heights has been investigated by ...

  11. 46 CFR 173.062 - Drainage of weather deck.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Drainage of weather deck. 173.062 Section 173.062 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSEL USE School Ships § 173.062 Drainage of weather deck. The weather deck of each sailing...

  12. Remediation of Acid Mine Drainage with Sulfate Reducing Bacteria

    Science.gov (United States)

    Hauri, James F.; Schaider, Laurel A.

    2009-01-01

    Sulfate reducing bacteria have been shown to be effective at treating acid mine drainage through sulfide production and subsequent precipitation of metal sulfides. In this laboratory experiment for undergraduate environmental chemistry courses, students design and implement a set of bioreactors to remediate acid mine drainage and explain observed…

  13. Thematic survey of subsurface drainage systems in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Tlapáková, L.; Žaloudík, J.; Kolejka, Jaromír

    2016-01-01

    Roč. 13, č. 2 (2016), s. 55-65 ISSN 1744-5647 Institutional support: RVO:68145535 Keywords : subsurface drainage system * remote sensing * image interpretation * drainage recognition and mapping Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 2.174, year: 2016 http://www.tandfonline.com/doi/full/10.1080/17445647.2016.1259129?scroll=top&needAccess=true

  14. Risk factors influencing the pleural drainage volume after transthoracic oesophagectomy.

    Science.gov (United States)

    Kosugi, Shin-ichi; Kanda, Tatsuo; Yajima, Kazuhito; Ishikawa, Takashi; Sakamoto, Kaoru

    2013-06-01

    The objective of this study was to clarify the factors influencing pleural drainage volume after transthoracic oesophagectomy and to determine criteria for the selection of patients who would benefit from the early removal of chest drains. Clinicopathological characteristics of 155 patients who underwent transthoracic oesophagectomy were prospectively collected, and the daily drainage volume of each patient was retrospectively reviewed. Potential risk factors were compared between the high-output group (n = 39) and low-output group (n = 116), which were dichotomized using the 75th percentile of total pleural drainage volume of the total study population. Multivariate logistic regression analyses were used to identify independent risk factors. The median duration of drainage was 10 days, with a median total drainage volume of 2258 ml. Of 27 potential risk factors influencing the drainage volume, creatinine clearance (P = 0.04), operative approach (P = 0.03) and thoracic duct removal (P = 0.01) were significantly associated with the total pleural drainage volume. The removal of the thoracic duct (P = 0.02; odds ratio, 4.02; 95% confidence interval 1.20-13.41) and lower creatinine clearance (P = 0.04; odds ratio, 1.02; 95% confidence interval 1.00-1.04) was independent risk factors for increased pleural drainage volume after transthoracic oesophagectomy. The early removal of chest drains may be possible in patients without these risk factors.

  15. Intermediate report on the problems of warm water drainage

    International Nuclear Information System (INIS)

    1976-01-01

    The investigation into the solution of the problems of warm water drainage and its related matters was conducted, and the result was summarized by the warm water drainage sectional committee of the central public nuisance-prevention council entrusted by the Environment Agency. The first section of this report deals with the background of the warm water drainage problems. In December 1970, the environmental pollution prevention act was revised so as to include warm water drainage in the law. The second section deals with the progress of deliberation by the sectional committee. The third section deals with the actual conditions of warm water drainage. The temperature difference at the inlet and outlet of water was 5 to 11 0 C in power plants, 5 to 16 0 C in iron and steel works, 4 to 11 0 C in petroleum refineries, and 7 to 25 0 C in petrochemical plants. The amount of heat energy discharged from power plants was greater than that from the others. Other sections deal with its effects on the living things in water, the forecast of diffusion of warm drainage, the concept of the regulation of warm drainage, and the present countermeasure. Twelve points which require future investigation are listed. They are the change in the phases of living things affected by the change in temperature and flow of warm drainage, the effects on fishery resources, the estimation system for the environmental calorific capacity in the sea, the mechanism of diffusion and the forecasting method for the diffusion range. (Iwakiri, K.)

  16. Assessment of drainage techniques for evacuation of chronic subdural hematoma

    DEFF Research Database (Denmark)

    Sjåvik, Kristin; Bartek, Jiri; Sagberg, Lisa Millgård

    2018-01-01

    OBJECTIVE Surgery for chronic subdural hematoma (CSDH) is one of the most common neurosurgical procedures. The benefit of postoperative passive subdural drainage compared with no drains has been established, but other drainage techniques are common, and their effectiveness compared with passive...

  17. Successful percutaneous transperineal drainage of a large prostatic abscess.

    Science.gov (United States)

    Mason, Barry M; Hakimi, A Ari; Clerkin, Kevin J; Silva, Jose V

    2010-12-01

    We present a case of an 83-year-old man with septic shock secondary to an extremely large prostatic abscess. Antibiotics and transperineal percutaneous drainage with a suprapubic-type Malecot catheter successfully treated the abscess. Follow-up images reveal resolution of the abscess. Broad-spectrum antibiotics and drainage permitted a full recovery. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. Predicting success of catheter drainage in infected necrotizing pancreatitis

    NARCIS (Netherlands)

    Hollemans, Robbert A.; Bollen, Thomas L.; Van Brunschot, Sandra; Bakker, Olaf J.; Ali, Usama Ahmed; Van Goor, Harry; Boermeester, Marja A.; Gooszen, Hein G.; Besselink, Marc G.; Van Santvoort, Hjalmar C.

    2016-01-01

    Introduction: At least 30% of patients with infected necrotizing pancreatitis are successfully treated with catheter drainage alone. It is currently not possible to predict which patients also need necrosectomy. We evaluated predictive factors for successful catheter drainage. Methods: This was a

  19. Predicting Success of Catheter Drainage in Infected Necrotizing Pancreatitis

    NARCIS (Netherlands)

    Hollemans, Robbert A.; Bollen, Thomas L.; van Brunschot, Sandra; Bakker, Olaf J.; Ahmed Ali, Usama; van Goor, Harry; Boermeester, Marja A.; Gooszen, Hein G.; Besselink, Marc G.; van Santvoort, Hjalmar C.

    2016-01-01

    At least 30% of patients with infected necrotizing pancreatitis are successfully treated with catheter drainage alone. It is currently not possible to predict which patients also need necrosectomy. We evaluated predictive factors for successful catheter drainage. This was a post hoc analysis of 130

  20. Predicting Success of Catheter Drainage in Infected Necrotizing Pancreatitis

    NARCIS (Netherlands)

    Hollemans, R.A.; Bollen, T.L.; Brunschot, S. van; Bakker, O.J.; Ali, U. Ahmed; Goor, H. van; Boermeester, M.A.; Gooszen, H.G.; Besselink, M.G.; Santvoort, H.C. van

    2016-01-01

    INTRODUCTION: At least 30% of patients with infected necrotizing pancreatitis are successfully treated with catheter drainage alone. It is currently not possible to predict which patients also need necrosectomy. We evaluated predictive factors for successful catheter drainage. METHODS: This was a

  1. Microbial decontamination of uranium mine drainage

    International Nuclear Information System (INIS)

    Hard, B.C.; Babel, W.

    2001-01-01

    One of the problems one is faced with when uranium mines are closed is the decontamination of acid mine drainage (AMD) from tailings and flooding of the underground mines. The high concentrations of sulfates and metals in mining water make it impossible to dispose of the water into rivers without having to decontaminate it first. A bioremediation process is proposed in which sulfate-reducing bacteria are used to remove metals, neutralize the water and reduce the sulfate concentrations. Methylotrophic sulfate-reducing strains have been isolated which can be used in such a process. Lab scale experiments with different reactor types were carried out in order to find the optimum design for this bioremediation process. Comparisons were made between methanol and other electron donors with regards to their suitability as substrate for this process. Methanol was found to be most suited. Laboratory data suggest that immobilizing the bacteria on pumice particles increases the sulfate-reduction rate (SRR) up to three fold to 18 mg/l.h, compared to the rates of free flowing cells of between 3.7 and 6.8 mg/l.h. Preliminary experiments on a larger scale (15 l) using acid mine drainage pH 2.5 show SRR of 0.71 mg/l.h. In biosorption experiments up to 140 mg of aluminium per g biomass was removed from the water. One strain was found to reduce uranium VI, thus changing it from the soluble to the insoluble form. The application of the proposed process with regards to bioremediation of AMD are discussed. (orig.)

  2. Foamed emulsion drainage: flow and trapping of drops.

    Science.gov (United States)

    Schneider, Maxime; Zou, Ziqiang; Langevin, Dominique; Salonen, Anniina

    2017-06-07

    Foamed emulsions are ubiquitous in our daily life but the ageing of such systems is still poorly understood. In this study we investigate foam drainage and measure the evolution of the gas, liquid and oil volume fractions inside the foam. We evidence three regimes of ageing. During an initial period of fast drainage, both bubbles and drops are very mobile. As the foam stabilises drainage proceeds leading to a gradual decrease of the liquid fraction and slowing down of drainage. Clusters of oil drops are less sheared, their dynamic viscosity increases and drainage slows down even further, until the drops become blocked. At this point the oil fraction starts to increase in the continuous phase. The foam ageing leads to an increase of the capillary pressure until the oil acts as an antifoaming agent and the foam collapses.

  3. Priority Scale of Drainage Rehabilitation of Cilacap City

    Science.gov (United States)

    Rudiono, Jatmiko

    2018-03-01

    Characteristics of physical condition of Cilacap City is relatively flat and low to sea level (approximately 6 m above sea level). In the event of a relatively heavy rainfall resulting in inundation at several locations. The problem of inundation is a serious problem if there is in a dense residential area or occurs in publicly-used infrastructure, such as roads and settlements. These problems require improved management of which include how to plan a sustainable urban drainage system and environmentally friendly. The development of Cilacap City is increasing rapidly, this causes drainage system based on the Drainage Masterplan Cilacap made in 2006 has not been able to accommodate rain water, so, it is necessary to evaluate the drainage masterplan for subsequent rehabilitation. Priority scale rehabilitation of the drainage sections as a guideline is an urgent need of rehabilitation in the next time period.

  4. Numerical Three-Dimensional Model of Airport Terminal Drainage System

    Directory of Open Access Journals (Sweden)

    Strzelecki Michał

    2014-03-01

    Full Text Available During the construction of an airport terminal it was found that as a result of the hydrostatic pressure of underground water the foundation plate of the building had dangerously shifted in the direction opposite to that of the gravitational forces. The only effective measure was to introduce a drainage system on the site. The complex geology of the area indicated that two independent drainage systems, i.e., a horizontal system in the Quaternary beds and a vertical system in the Tertiary water-bearing levels, were necessary. This paper presents numerical FEM calculations of the two drainage systems being part of the airport terminal drainaged esign. The computer simulation which was carried out took into consideration the actual effect of the drainage systems and their impact on the depression cone being formed in the two aquifers.

  5. AGRICULTURAL POLICIES AND COMPETITION IN WORLD AGRICULTURE

    Directory of Open Access Journals (Sweden)

    Raluca Duma

    2011-04-01

    Full Text Available Agricultural policies have had a guiding role inagriculture development and implicitly in their marketing. Usually they belongto each state and government and are issued in accordance with their specificclimate, social-economic and cultural background which includes food andgastronomic traditions. Agricultural policies have in view home and foreignmarket demand, as well as the socio-demographic, political and military contextat a certain point in the socio-economic development

  6. Subdural drainage versus subperiosteal drainage in burr-hole trepanation for symptomatic chronic subdural hematomas.

    Science.gov (United States)

    Bellut, David; Woernle, Christoph Michael; Burkhardt, Jan-Karl; Kockro, Ralf Alfons; Bertalanffy, Helmut; Krayenbühl, Niklaus

    2012-01-01

    Symptomatic chronic subdural hematoma (scSDH) is one of the most frequent diseases in neurosurgical practice, and its incidence is increasing. However, treatment modalities are still controversial. The aim of this retrospective single-center study is to compare for the first time two surgical methods in the treatment of subdural hematoma that have been proven to be efficient in previous studies in a direct comparison. We analyzed the data of 143 scSDHs in 113 patients undergoing surgery for subdural hematoma with placement of subperiosteal or subdural drainage after double burr-hole trepanation for hematoma evacuation. Overall, there were no statistically significant differences regarding general patient characteristics, preoperative and postoperative symptoms, postoperative hematoma remnant, rates of recurrences, mortality, complications, and outcome at discharge and at 3-month follow up between the groups. There was a close to significant tendency of lower mortality after placement of subperiosteal drainage system and a tendency towards lower rate of recurrent hematoma after placement of subdural drainage system. Our study shows for the first time a direct comparison of two mainly used surgical techniques in the treatment of scSDH. Both methods proved to be highly effective, and general patient data, complications, outcome and mortality of both groups are equal or superior compared with previously published series. Because there is a clear tendency to less mortality and fewer serious complications, treatment with double burr-hole trepanation, irrigation, and placement of subperiosteal drainage is our treatment of choice in patients with predictable high risk of complications. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. The LACDA (Los Angeles County Drainage Area) System Recreation Study, Los Angeles County Drainage Area.

    Science.gov (United States)

    1980-03-01

    Channel Islands and is not conveniently situ - tions, potential benefits are greatly increased by con- ated for the daily use of large numbers of people...are at least three races of birds and some plant species on the peninsula that are found nowhere else except the Channel Islands. 32. Agua Amarga Canyon...Class 3 (4,5,7) Agua Amarga Canyon is the last remaining relatively undisturbed drainage on the coastal side of the Palos Verdes Peninsula. There

  8. Proceedings of the international land reclamation and mine drainage conference and third international conference on the abatement of acidic drainage. Volume 1: Mine drainage -- SP 06A-94

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    Volume 1 of these proceedings is divided into the following sections: Modeling mine water quality; Water treatment with wetlands; Predicting mine water quality; Water treatment--Chemical; Control of acid mine drainage--Wet covers; Site characterization monitoring; Control of acid mine drainage--Alkaline addition; and Mine water geochemistry. Papers dealing with or applicable to coal or uranium mining have been processed separately for inclusion on the data base

  9. Farmer driven national monitoring of nitrogen concentrations in drainage water in Denmark

    Science.gov (United States)

    Piil, Kristoffer; Lemming, Camilla; Kolind Hvid, Søren; Knudsen, Leif

    2014-05-01

    Field drains are often considered to short circuit the hydrological cycle in agricultural catchments and lead to an increased risk of nitrogen loss to the environment. Because of increased regulation of agricultural practices due to catchment management plans, resulting from the implementation of the water frame directive, Danish farmers pushed for a large scale monitoring of nitrogen loss from field drains. Therefore, the knowledge centre for agriculture, Denmark, organized a three year campaign where farmers and local agricultural advisory centres collected water samples from field drains three to five times during the winter season. Samples were analysed for nitrate and total nitrogen. Combined, more than 600 drains were monitored over the three years. During the first two years of monitoring, average winter concentrations of total nitrogen ranged from 0.1 mg N L-1 to 31.1 mg N L-1, and the fraction of total nitrogen present as nitrate ranged from 0% to 100%. This variation is much larger than what is observed in the Danish national monitoring and assessment programme, which monitors only a few drains in selected catchments. Statistical analysis revealed that drainage water nitrogen concentrations were significantly correlated to the cropping system and the landscape type (high ground/lowlands/raised seabed) in which the monitored fields were situated. The average total nitrogen concentration was more than 2 mg N L-1 lower on raised seabed than on high ground, and the average fraction of total nitrogen present as nitrate was more than 20% lower. This indicates that substantial nitrate reduction occurs at or above the drain depth on raised sea flats, in particular in the north of Denmark. This inherent nitrogen retention on raised seabed is not taken into account in the current environmental regulation, nor in the first generation catchment management plans. The monitoring program demonstrated large variation in nitrogen concentrations in drainage water, in

  10. Sequestration of phosphorus by acid mine drainage floc

    Science.gov (United States)

    Adler, P.R.; Sibrell, P.L.

    2003-01-01

    Solubilization and transport of phosphorus (P) to the water environment is a critical environmental issue. Flocs resulting from neutralizing acid mine drainage (AMD) were tested as a possible lowcost amendment to reduce the loss of soluble P from agricultural fields and animal wastewater. Flocs were prepared by neutralizing natural and synthetic solutions of AMD with limestone, lime, ammonium hydroxide, and sodium hydroxide. Phosphorus sequestration was tested in three distinct environments: water, soil, and manure storage basins. In water, flocs prepared from AMD adsorbed 10 to 20 g P kg-1 dry floc in equilibrium with 1 mg L-1 soluble P. Similar results were observed for both Fe-based and A1-based synthetic flocs. A local soil sample adsorbed about 0.1 g P kg-1, about two orders of magnitude less. The AMD-derived flocs were mixed with a highP soil at 5 to 80 g floc kg-1 soil, followed by water and acid (Mehlich1) extractions. All flocs performed similarly. About 70% of the waterextractable P was sequestered by the floc when applied at a rate of 20 g floc kg-1 soil, whereas plant-available P only decreased by about 30%. Under anaerobic conditions simulating manure storage basins, all AMD flocs reduced soluble P by greater than 95% at a rate of 0.2 g floc g-1 rainbow trout (Oncorhynchus mykiss) manure. These findings indicate that AMD flocs could be an effective agent for preventing soluble P losses from soil and manure to the water environment, while at the same time decreasing the costs associated with AMD treatment.

  11. Population pressure and agricultural productivity in Bangladesh.

    Science.gov (United States)

    Chaudhury, R H

    1983-01-01

    The relationship between population pressure or density and agricultural productivity is examined by analyzing the changes in the land-man ratio and the changes in the level of land yield in the 17 districts of Bangladesh from 1961-64 and 1974-77. The earlier years were pre-Green Revolution, whereas in the later years new technology had been introduced in some parts of the country. Net sown area, value of total agricultural output, and number of male agricultural workers were the main variables. For the country as a whole, agricultural output grew by 1.2%/year during 1961-64 to 1974-77, while the number of male agricultural workers grew at 1.5%/year. The major source of agricultural growth during the 1960s was found to be increased land-yield associated with a higher ratio of labor to land. The findings imply that a more intensified pattern of land use, resulting in both higher yield and higher labor input/unit of land, is the main source of growth of output and employment in agriculture. There is very little scope for extending the arable area in Bangladesh; increased production must come from multiple cropping, especially through expansion of irrigation and drainage, and from increases in per acre yields, principly through adoption of high yield variants, which explained 87% of the variation in output per acre during the 1970s. Regional variation in output was also associated with variation in cropping intensity and proportion of land given to high yield variants. There is considerable room for modernizing agricultural technology in Bangladesh: in 1975-76 less than 9% of total crop land was irrigated and only 12% of total acreage was under high yield variants. The adoption of new food-grain technology and increased use of high yield variants in Bangladesh's predominantly subsistence-based agriculture would require far-reaching institutional and organizational changes and more capital. Without effective population control, expansion of area under high yield

  12. Integrating Phytoextraction and Biofortification: Fungal Accumulation of Selenium in Plant Materials from Phytoremediation of Agricultural Drainage

    Science.gov (United States)

    The phytomanagement of Se-polluted soil and water is one strategy that may be environmentally sustainable and cost-effective for soils and waters enriched with natural-occurring Se. Several plant species, including Indian mustard (Brassica juncea), pickleweed (Salicornia bigelovii), and other salt/S...

  13. Ditch network maintenance in peatland forest as a private investment: short- and long-term effects on financial performance at stand level

    Directory of Open Access Journals (Sweden)

    T. Penttilä

    2008-03-01

    Full Text Available In Finland, most of the suitable peatland has now been ditched for forestry purposes, and ditch network maintenance (DNM is carried out on 70,000–80,000 hectares of land each year. We examined the financial performance of DNM operations on 44 sample plots representing two medium-quality site types located within two different climatic regions in northern Finland. We applied a simulation approach in which actual measurements of trees growing on sample plots were fed into a stand simulator (MOTTI which predicted stand development with and without DNM. The financial assessments involved calculating short-term and long-term effects of DNM by applying, respectively, ROI (return on investment and NPV (net present value analyses. The results indicated that the financial performance of DNM, particularly in the short term, was highly dependent on the availability of government subsidies. Without the DNM subsidy, the return on investment was between 1.6% and 3.7%; whereas with government subsidy it ranged from 3.8% to 8.4%. In the long run, the net present value was ca. 4–14% higher for stands with DNM than for those without.

  14. 7. Food and agriculture

    International Nuclear Information System (INIS)

    Livernash, R.

    1992-01-01

    Global food production has increased substantially over the past two decades, but factors such as population pressures and environmental degradation are undermining agriculture's current condition and future prospects. This chapter discusses the following: global trends; production trends (livestock and fisheries); per capita production trends (population density and agriculture); environmental trends (soil degradation, inputs of fertilizers, pesticides, and freshwater); economic trends (agricultural commodity prices, declining investment in irrigation, World Bank lending); trade liberalization and the Gatt negotiations; conventional agriculture and alternative agriculture; problems with the conventional model (on-farm impacts, off-farm impacts); agricultural policies - creating a new environment; policy impacts - distorted price structures; new policy options (reducing input subsidies, land conservation programs, management agreements, taxes, fees, and tax incentives, strengthening regulations, subsidizing conversion); the economics of alternative agriculture

  15. Unilobar versus bilobar biliary drainage: effect on quality of life and bilirubin level reduction

    Directory of Open Access Journals (Sweden)

    Shivanand Gamanagatti

    2016-01-01

    Conclusion: Percutaneous biliary drainage provides good palliation of malignant obstructive jaundice. Partial-liver drainage achieved results as good as those after complete liver drainage with significant improvements in QOL and reduction of the bilirubin level.

  16. Effectiveness of submerged drains in reducing subsidence of peat soils in agricultural use, and their effects on water management and nutrient loading of surface water: modelling of a case study in the western peat soil area of The Netherlands

    Science.gov (United States)

    Hendriks, Rob F. A.; van den Akker, Jan J. A.

    2017-04-01

    Effectiveness of submerged drains in reducing subsidence of peat soils in agricultural use, and their effects on water management and nutrient loading of surface water: modelling of a case study in the western peat soil area of The Netherlands In the Netherlands, about 8% of the area is covered by peat soils. Most of these soils are in use for dairy farming and, consequently, are drained. Drainage causes decomposition of peat by oxidation and accordingly leads to surface subsidence and greenhouse gas emission. Submerged drains that enhance submerged infiltration of water from ditches during the dry and warm summer half year were, and are still, studied in The Netherlands as a promising tool for reducing peat decomposition by raising groundwater levels. For this purpose, several pilot field studies in the Western part of the Dutch peat area were conducted. Besides the effectiveness of submerged drains in reducing peat decomposition and subsidence by raising groundwater tables, some other relevant or expected effects of these drains were studied. Most important of these are water management and loading of surface water with nutrients nitrogen, phosphorus and sulphate. Because most of these parameters are not easy to assess and all of them are strongly depending on the meteorological conditions during the field studies some of these studies were modelled. The SWAP model was used for evaluating the hydrological results on groundwater table and water discharge and recharge. Effects of submerged drains were assessed by comparing the results of fields with and without drains. An empirical relation between deepest groundwater table and subsidence was used to convert effects on groundwater table to effects on subsidence. With the SWAP-ANIMO model nutrient loading of surface water was modelled on the basis of field results on nutrient concentrations . Calibrated models were used to assess effects in the present situation, as thirty-year averages, under extreme weather

  17. Phosphorus and water budgets in an agricultural basin.

    Science.gov (United States)

    Faridmarandi, Sayena; Naja, Ghinwa M

    2014-01-01

    Water and phosphorus (P) budgets of a large agricultural basin located in South Florida (Everglades Agricultural Area, EAA) were computed from 2005 to 2012. The annual surface outflow P loading from the EAA averaged 157.2 mtons originating from Lake Okeechobee (16.4 mtons, 10.4%), farms (131.0 mtons, 83.4%), and surrounding basins (9.8 mtons, 6.2%) after attenuation. Farms, urban areas, and the adjacent C-139 basin contributed 186.1, 15.6, and 3.8 mtons/yr P to the canals, respectively. The average annual soil P retention was estimated at 412.5 mtons. Water and P budgets showed seasonal variations with high correlation between rainfall and P load in drainage and surface outflows. Moreover, results indicated that the canals acted as a P sink storing 64.8 mtons/yr. To assess the P loading impact of farm drainage on the canals and on the outflow, dimensionless impact factors were developed. Sixty-two farms were identified with a high and a medium impact factor I1 level contributing 44.5% of the total drainage P load to the canals, while their collective area represented less than 23% of the EAA area (172 farms). Optimizing the best management practice (BMP) strategies on these farms could minimize the environmental impacts on the downstream sensitive wetlands areas.

  18. The effects of ferulic acid on the pharmacokinetics of warfarin in rats after biliary drainage

    Directory of Open Access Journals (Sweden)

    Li H

    2016-07-01

    Full Text Available Haigang Li,1,2 Yang Wang,1 Rong Fan,1 Huiying Lv,3 Hua Sun,4 Haitang Xie,4 Tao Tang,1 Jiekun Luo,1 Zian Xia1 1Department of Integrated Traditional Chinese and Western Medicine, Laboratory of Ethnopharmacology, Xiangya Hospital, Central South University, 2Department of Pharmacy, Changsha Medical University, 3Hunan Agricultural Product Processing Institute, Hunan Academy of Agricultural Sciences, Changsha, 4Anhui Provincial Centre for Drug Clinical Evaluation, Yijishan Hospital of Wannan Medical College, Wuhu, People’s Republic of China Abstract: According to previous research studies, warfarin can be detected in human bile after oral administration. Ferulic acid (FA is the main bioactive component of many Chinese herbs for the treatment of cardiovascular disease. To elucidate the effects of FA on the pharmacokinetics of warfarin in rats after biliary drainage is necessary. Twenty rats were randomly divided into four groups: Group 1 (WN: healthy rats after the administration of warfarin sodium, Group 2 (WO: a rat model of biliary drainage after the administration of warfarin sodium, Group 3 (WFN: healthy rats after the administration of warfarin sodium and FA, and Group 4 (WFO: a rat model of biliary drainage after the administration of warfarin sodium and FA. Blood samples were collected at different time points after administration. The concentrations of blood samples were determined by ultraperformance liquid chromatography–tandem mass spectrometry. Comparisons between groups were performed according to the main pharmacokinetic parameters calculated by the DAS 2.1.1 software. The pharmacokinetic parameters showed a significant difference between the WN and WO groups, the WO group showed a decrease of 51% and 41.6% in area under the curve from 0 to time (AUC0–t and peak plasma concentration (Cmax, respectively, whereas time to Cmax (Tmax was delayed 3.27 folds. There were significant differences between the WFO and WFN groups, the WFO

  19. Seasonal and interspecific nutrient mitigation comparisons of three emergent aquatic macrophytes

    Science.gov (United States)

    The purpose of this experiment was to measure both summer and winter nutrient mitigation efficiencies of three aquatic plants found in agricultural drainage ditches in the lower Mississippi River Basin. Mesocosms (1.25 x 0.6 x 0.8 m) were filled with sediment and planted with monocultures of one of...

  20. Preoperative biliary drainage in hilar cholangiocarcinoma: When and how?

    Science.gov (United States)

    Paik, Woo Hyun; Loganathan, Nerenthran; Hwang, Jin-Hyeok

    2014-01-01

    Hilar cholangiocarcinoma is a tumor of the extrahepatic bile duct involving the left main hepatic duct, the right main hepatic duct, or their confluence. Biliary drainage in hilar cholangiocarcinoma is sometimes clinically challenging because of complexities associated with the level of biliary obstruction. This may result in some adverse events, especially acute cholangitis. Hence the decision on the indication and methods of biliary drainage in patients with hilar cholangiocarcinoma should be carefully evaluated. This review focuses on the optimal method and duration of preoperative biliary drainage (PBD) in resectable hilar cholangiocarcinoma. Under certain special indications such as right lobectomy for Bismuth type IIIA or IV hilar cholangiocarcinoma, or preoperative portal vein embolization with chemoradiation therapy, PBD should be strongly recommended. Generally, selective biliary drainage is enough before surgery, however, in the cases of development of cholangitis after unilateral drainage or slow resolving hyperbilirubinemia, total biliary drainage may be considered. Although the optimal preoperative bilirubin level is still a matter of debate, the shortest possible duration of PBD is recommended. Endoscopic nasobiliary drainage seems to be the most appropriate method of PBD in terms of minimizing the risks of tract seeding and inflammatory reactions. PMID:24634710

  1. Thoracoscopic Surgery for Pneumothorax Following Outpatient Drainage Therapy.

    Science.gov (United States)

    Sano, Atsushi; Yotsumoto, Takuma

    2017-10-20

    We investigated the outcomes of surgery for pneumothorax following outpatient drainage therapy. We reviewed the records of 34 patients who underwent operations following outpatient drainage therapy with the Thoracic Vent at our hospital between December 2012 and September 2016. Indications for outpatient drainage therapy were pneumothorax without circulatory or respiratory failure and pleural effusion. Indications for surgical treatment were persistent air leakage and patient preference for surgery to prevent or reduce the incidence of recurrent pneumothorax. Intraoperatively, 9 of 34 cases showed loose adhesions around the Thoracic Vent, all of which were dissected bluntly. The preoperative drainage duration ranged from 5 to 13 days in patients with adhesions and from 3 to 19 days in those without adhesions, indicating no significant difference. The duration of preoperative drainage did not affect the incidence of adhesions. The operative duration ranged from 30 to 96 minutes in patients with adhesions and from 31 to 139 minutes in those without adhesions, also indicating no significant difference. Outpatient drainage therapy with the Thoracic Vent was useful for spontaneous pneumothorax patients who underwent surgery, and drainage for less than 3 weeks did not affect intraoperative or postoperative outcomes.

  2. Contribution of computed tomography on chest drainage guidance

    International Nuclear Information System (INIS)

    Douvlou, E.; Tzortzis, D.; Vlachou, I.; Petrocheilou, G.; Safarika, V.; Fragopoulou, L.; Stathopoulou, S.; Kokkinis, C.

    2012-01-01

    Full text: Introduction: Thoracic collections (encysted pleural, endopulmonary, mediastinal) are common findings in major trauma hospitals mainly in need of further treatment as drainage. Objectives and tasks: To evaluate the CT-guidance, as a method of choice for thoracic drainages. Material and methods: 35 CT-guided chest drainages were performed for diagnostic and therapeutic purpose in 33 patients, with a mean age of 62 years. Of the 35 drainages, 31 were encysted at the pleura, 3 of them were endopulmonary and 1 was in the mediastinum. During the procedure we used needles of 15cm long and 18-22 G diameter for small collections while for 'large' collections drainage catheters of 10-16 F were placed. Results: All the CT-guided drainages of the chest were successful. Of them, 7 were pleural effusion collections while 24 were exudate collections (18 inflammatory and 6 neoplastic) and all were developed in the lungs or the mediastinum. In all the cases that a catheter was placed, full removal of the collections was achieved leading to a remarkable improvement of the patient's condition. Non-significant pneumothorax and tiny endopulmonary bleeding were the complications that occurred. Conclusion: CT-guided drainage of thoracic collections is an accurate and secure procedure and achieves high diagnostic and therapeutic results

  3. Copper isotope fractionation in acid mine drainage

    Science.gov (United States)

    Kimball, B.E.; Mathur, R.; Dohnalkova, A.C.; Wall, A.J.; Runkel, R.L.; Brantley, S.L.

    2009-01-01

    We measured the Cu isotopic composition of primary minerals and stream water affected by acid mine drainage in a mineralized watershed (Colorado, USA). The ??65Cu values (based on 65Cu/63Cu) of enargite (??65Cu = -0.01 ?? 0.10???; 2??) and chalcopyrite (??65Cu = 0.16 ?? 0.10???) are within the range of reported values for terrestrial primary Cu sulfides (-1??? waters (1.38??? ??? ??65Cu ??? 1.69???). The average isotopic fractionation (??aq-min = ??65Cuaq - ??65Cumin, where the latter is measured on mineral samples from the field system), equals 1.43 ?? 0.14??? and 1.60 ?? 0.14??? for chalcopyrite and enargite, respectively. To interpret this field survey, we leached chalcopyrite and enargite in batch experiments and found that, as in the field, the leachate is enriched in 65Cu relative to chalcopyrite (1.37 ?? 0.14???) and enargite (0.98 ?? 0.14???) when microorganisms are absent. Leaching of minerals in the presence of Acidithiobacillus ferrooxidans results in smaller average fractionation in the opposite direction for chalcopyrite (??aq-mino = - 0.57 ?? 0.14 ???, where mino refers to the starting mineral) and no apparent fractionation for enargite (??aq-mino = 0.14 ?? 0.14 ???). Abiotic fractionation is attributed to preferential oxidation of 65Cu+ at the interface of the isotopically homogeneous mineral and the surface oxidized layer, followed by solubilization. When microorganisms are present, the abiotic fractionation is most likely not seen due to preferential association of 65Cuaq with A. ferrooxidans cells and related precipitates. In the biotic experiments, Cu was observed under TEM to occur in precipitates around bacteria and in intracellular polyphosphate granules. Thus, the values of ??65Cu in the field and laboratory systems are presumably determined by the balance of Cu released abiotically and Cu that interacts with cells and related precipitates. Such isotopic signatures resulting from Cu sulfide dissolution should be useful for acid mine drainage

  4. Superficial drainage studies in open-pit mines

    International Nuclear Information System (INIS)

    Teixeira Junior, P.B.; Leite, C.B.B.

    1984-01-01

    Drainage studies concerning large open-pit mining projects can be of vital importance throughout the mining activity itself as they may assist in avoiding activity interruptions due to drainage problems, therefore representing substantial savings. These studies should, in fact, be carried out from the initial activity stages and shall be considered in operational, project and planning decisions in order to optimize results and reduce costs. This specific study presents a drainage study systematization proposal, enphasazing economic decision criteria. The authors comment on studies of this nature developed at the Caldas uranium mine - NUCLEBRAS. (D.J.M.) [pt

  5. Vacuum-assisted drainage in cardiopulmonary bypass: advantages and disadvantages.

    Science.gov (United States)

    Carvalho Filho, Elio Barreto de; Marson, Fernando Augusto de Lima; Costa, Loredana Nilkenes Gomes da; Antunes, Nilson

    2014-01-01

    Systematic review of vacuum assisted drainage in cardiopulmonary bypass, demonstrating its advantages and disadvantages, by case reports and evidence about its effects on microcirculation. We conducted a systematic search on the period 1997-2012, in the databases PubMed, Medline, Lilacs and SciELO. Of the 70 selected articles, 26 were included in the review. Although the vacuum assisted drainage has significant potential for complications and requires appropriate technology and professionalism, prevailed in literature reviewed the concept that vacuum assisted drainage contributed in reducing the rate of transfusions, hemodilutions, better operative field, no significant increase in hemolysis, reduced complications surgical, use of lower prime and of smaller diameter cannulas.

  6. Peritoneal seeding of cholangiocarcinoma in patients with percutaneous biliary drainage

    International Nuclear Information System (INIS)

    Miller, G.A. Jr.; Heaston, D.K.; Moore, A.V. Jr.; Mills, S.R.; Dunnick, N.R.

    1983-01-01

    Percutaneous transhepatic catheter decompression is performed increasingly as an adjunct or alternative to surgery in patients with benign or malignant biliary obstruction. The authors recently saw three patients with cholangiocarcinoma in whom metastatic seeding of the peritoneal serosa was identified some months after initial percutaneous transhepatic biliary drainage. Although no tumor was found along the hepatic tract of the biliary drainage catheters to implicate the drainage tubes as the direct source of peritoneal spread, the occurrence of this rare type of metastasis of cholangiocarcinoma in patients with potential access of tumor cells to the peritoneal cavity via the catheter tracts does suggest such a relation. The clinical history of one patient is presented

  7. Agriculture and environmental pollution

    International Nuclear Information System (INIS)

    Iqbal, M.M.; Idris, M.; Shah, S.M.

    1997-01-01

    Agriculture is a profession which is open both to natural conditions and intense human activity. This has brought it in direct interface with the environment. The activities related to agriculture can have favorable as well as unfavorable influence on environment. Pressure of burgeoning population in demanding increased production from agriculture to feed and clothe the teeming millions. This has resulted in excessive use of soil, fertilizers and pesticides. The paper describes the effect of these productive resources on environment and human health. (author)

  8. Functional Topology of Evolving Urban Drainage Networks

    Science.gov (United States)

    Yang, Soohyun; Paik, Kyungrock; McGrath, Gavan S.; Urich, Christian; Krueger, Elisabeth; Kumar, Praveen; Rao, P. Suresh C.

    2017-11-01

    We investigated the scaling and topology of engineered urban drainage networks (UDNs) in two cities, and further examined UDN evolution over decades. UDN scaling was analyzed using two power law scaling characteristics widely employed for river networks: (1) Hack's law of length (L)-area (A) [L∝Ah] and (2) exceedance probability distribution of upstream contributing area (δ) [P>(A≥δ>)˜aδ-ɛ]. For the smallest UDNs ((A≥δ>) plots for river networks are abruptly truncated, those for UDNs display exponential tempering [P>(A≥δ>)=aδ-ɛexp⁡>(-cδ>)]. The tempering parameter c decreases as the UDNs grow, implying that the distribution evolves in time to resemble those for river networks. However, the power law exponent ɛ for large UDNs tends to be greater than the range reported for river networks. Differences in generative processes and engineering design constraints contribute to observed differences in the evolution of UDNs and river networks, including subnet heterogeneity and nonrandom branching.

  9. Prognostic factors after percutaneous transhepatic biliary drainage

    International Nuclear Information System (INIS)

    Castoldi, M.C.; Cozzi, G.; Severini, A.; Pisani, P.; Ideo, G.; Bellomi, M.

    1991-01-01

    The authors reviewed the clinical charts and the radiographic files of 93 patients with obsructive jaundice -in 86 cases due to neoplasms -treated with PTBD. The test of differences from survival curves was used to identify the clinical parameters predictive of short survival after PTBD. The difference in survival curves was significant relative to serum indirect bilirubin (cut point: 7.6 mg%), to serum cholinesterase (cut point: 1290 mU/ml), to white blood cells counts (cut point: 8600/mm 3 ), to blood urea nitrogen (BUN) levels (cut point: 60 mg%). Because of the market negative prognostic value of high BUN levels, our data seemto indicate that PTBD should not be performed when severe renal insufficiency is present. Other parameters correlated with a short survival after PTBD were the histotype of metastasis (in comparison with the other ones) and in large neoplastic volume (in comparison with a small and medium ones). Through pre-PTBD radiological and laboratory data analysis, a group of patients can be selected in whom the procedure will increase neither well-being nor survival, as plotted against those patients who are likely to benefit from biliary drainage

  10. DROUGHT ANALYSIS IN OZANA DRAINAGE BASIN

    Directory of Open Access Journals (Sweden)

    Marina IOSUB

    2016-03-01

    Full Text Available Ozana drainage basin is located at the contact between large landscape units (the Carpathian mountains, the Subcarpathian area, and the plateau region. This placement determines the existence of a complex climate in the region. Despite being small in size, and its extension on an W-E direction, differences can be observed, especially of the way extreme phenomena take place. In the case of droughts, it had different intensities in the mountains, compared to the plateau region. In order to emphasize the different distribution on the territory, several climatic indexes have been calculated, regarding dryness (De Martonne Index, Hellman criterion. The analysis of these indexes at the same monitoring stations (Pluton, Leghin and Dumbrava emphasizes the growth of the drought periods in the plateau region and the fact that they shorten in the mountain area. In the mountainous area, where the land is very well forested, the values of the De Martonne index can reach 45.4, and in the plateau regions, where the forest associations are sparse, the values dropped to 30.6. According to the Hellman criterion, several differences can be emphasized, at basin level. In the mountainous region, there is only one month that, at a multi-annual level, has stood up among the rest, as being excessively droughty, while in the median /central region of the basin, three months have been identified, that have such potential, as well as five months, at Dumbrava.

  11. Origin of acid mine drainage in Enugu

    International Nuclear Information System (INIS)

    Uma, K.O.

    1992-01-01

    Mine flooding is a serious problem in the Enugu Coal Mines and has led to the abandonment of two of the four mines. About 1800 m 3 of water is pumped out daily from the mines into the nearby streams. The source of this enormous volume of water has been established based on the hydrodynamics and hydrology of the area. Two prolific aquifers - an unconfined and a confined system - overlie the mines, but the mine water is derived principally from the unconfined aquifer. The pathway of flow is, provided by the numerous fractures connecting the two aquifers and the mine tunnel. The major hydrochemical activity resulting in pollution of the mine water occurs within the sumps in the floor of the longwalls. These sumps act as oxidation chambers where groundwater from the fractures mixes and subsequently reacts with sulfur-rich solutes released by coal mining. Contrary to general belief, the mine drainage has not seriously degraded the chemistry of receiving streams. The pH and electric conductivity, representing, the dissolved ions, were increased less than 10% of the values in the unaffected region

  12. Integrated urban drainage, status and perspectives.

    Science.gov (United States)

    Harremoës, P

    2002-01-01

    This paper summarises the status of urban storm drainage as an integrated professional discipline, including the management-policy interface, by which the goals of society are implemented. The paper assesses the development of the discipline since the INTERURBA conference in 1992 and includes aspects of the papers presented at the INTERURBA-II conference in 2001 and the discussions during the conference. Tools for integrated analysis have been developed, but there is less implementation than could be expected. That is due to lack of adequate knowledge about important mechanisms, coupled with a significant conservatism in the business. However, significant integrated analyses have been reported. Most of them deal with the sewer system and the treatment plant, while few incorporate the receiving water as anything but the object of the loads to be minimised by engineering measures up-stream. Important measures are local infiltration, source control, storage basins, local treatment and real time control. New paradigms have been introduced: risk of pollution due to system failure, technology for water reuse, sustainability, new architecture and greener up-stream solutions as opposed to down-stream concrete solutions. The challenge is to combine the inherited approaches with the new approaches by flexibility and adaptability.

  13. Lignor process for acidic rock drainage treatment.

    Science.gov (United States)

    Zhuang, J M; Walsh, T

    2004-09-01

    The process using lignosulfonates for acidic rock drainage (ARD) treatment is referred to as the Lignor process. Lignosulfonates are waste by-products produced in the sulfite pulping process. The present study has shown lignosulfonates are able to protect lime from developing an external surface coating, and hence to favor its dissociation. Further, the addition of lignosulfonates to ARD solutions increased the dotting and settling rate of the formed sludge. The capability of lignosulfonates to form stable metal-lignin complexes makes them very useful in retaining metal ions and thus improving the long-term stability of the sludge against leaching. The Lignor process involves metal sorption with lignosulfonates, ARD neutralization by lime to about pH 7, pH adjustment with caustic soda to 9.4 - 9.6, air oxidation to lower the pH to a desired level, and addition of a minimum amount of FeCl3 for further removal of dissolved metals. The Lignor process removes all concerned metals (especially Al and Mn) from the ARD of the Britannia Mine (located at Britannia Beach, British Columbia, Canada) to a level lower than the limits of the B.C. Regulations. Compared with the high-density sludge (HDS) process, the Lignor process has many advantages, such as considerable savings in lime consumption, greatly reduced sludge volume, and improved sludge stability.

  14. MASH TEST NO. 3-10 OF A NON-PROPRIETARY, HIGH-TENSION CABLE MEDIAN BARRIER FOR USE IN 6H:1V V-DITCH (TEST NO. MWP-8)

    Science.gov (United States)

    2017-05-10

    The Midwest States Pooled Fund Program has been developing a prototype design for a non-proprietary, high-tension cable median barrier for use in a 6H:1V V-ditch. This system incorporates four evenly spaced cables, Midwest Weak Posts (MWP) spaced at ...

  15. Malawi - Conservation Agriculture

    Data.gov (United States)

    Millennium Challenge Corporation — The randomized control trial impact evaluation tests different strategies for communicating information about agricultural technologies to smallholder maize farmers...

  16. Energy in agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Le Roux, E J

    1980-02-01

    Agriculture is an important component of Canadian energy policy. There are many opportunities for both the production of energy from agricultural processes and the conservation of energy in agricultural production. These opportunities, as well as current practices and research in progress, are outlined in this report. Energy sources in agriculture include biomass (straw and other residues), methane production from manure, and oil and alcohol from crops. Alternate energy sources such as solar and wind power conserve conventional resources, and additional conservation opportunities exist in the use of greenhouses, waste heat and energy-efficient farming processes. Research programs and possible trends are outlined. 10 figs., 3 tabs.

  17. Agriculture - reconciling ancient tensions

    Directory of Open Access Journals (Sweden)

    David Atkinson

    2002-09-01

    Full Text Available Decision-making in agriculture has tended to be driven by factors other than environmental concerns. This may be changing, and perhaps the emphases of the two creation accounts in Genesis (responsible management or 'dominion', and active care may become more important. The paper examines a number of current developments in agriculture (synthetic fertilizers and pesticides, genetic manipulation, and organic versus industrial methodologies and discusses the issues they raise for agricultural productivity and the human communities dependent on farming. The questions raised are complex; we are faced with establishing a new paradigm for agricultural practice.

  18. Agriculture. Pt. 2

    International Nuclear Information System (INIS)

    1994-01-01

    The climatic effects of agriculture and nutritional habits of the West German population are investigated. Changes in solar UV-B radiation and methods of measuring them are described. The climatic relevance of ecological and conventional agricultural techniques are compared. The agricultural policy of the European Communities is presented and discussed. The climatic effects of the totality of agricultural production techniques and processing stages of the food industry, as well as of transport and trade, are analyzed. Sociological investigations are made of the nutritional habits of the population, and the consequences for the global climate are compared. (SR) [de

  19. Implications of deep drainage through saline clay for groundwater recharge and sustainable cropping in a semi-arid catchment, Australia

    Directory of Open Access Journals (Sweden)

    W. A. Timms

    2012-04-01

    Full Text Available The magnitude and timing of deep drainage and salt leaching through clay soils is a critical issue for dryland agriculture in semi-arid regions (<500 mm yr−1 rainfall, potential evapotranspiration >2000 mm yr−1 such as parts of Australia's Murray-Darling Basin (MDB. In this rare study, hydrogeological measurements and estimations of the historic water balance of crops grown on overlying Grey Vertosols were combined to estimate the contribution of deep drainage below crop roots to recharge and salinization of shallow groundwater. Soil sampling at two sites on the alluvial flood plain of the Lower Namoi catchment revealed significant peaks in chloride concentrations at 0.8–1.2 m depth under perennial vegetation and at 2.0–2.5 m depth under continuous cropping indicating deep drainage and salt leaching since conversion to cropping. Total salt loads of 91–229 t ha−1 NaCl equivalent were measured for perennial vegetation and cropping, with salinity to ≥ 10 m depth that was not detected by shallow soil surveys. Groundwater salinity varied spatially from 910 to 2430 mS m−1 at 21 to 37 m depth (N = 5, whereas deeper groundwater was less saline (290 mS m−1 with use restricted to livestock and rural domestic supplies in this area. The Agricultural Production Systems Simulator (APSIM software package predicted deep drainage of 3.3–9.5 mm yr−1 (0.7–2.1% rainfall based on site records of grain yields, rainfall, salt leaching and soil properties. Predicted deep drainage was highly episodic, dependent on rainfall and antecedent soil water content, and over a 39 yr period was restricted mainly to the record wet winter of 1998. During the study period, groundwater levels were unresponsive to major rainfall events (70 and 190 mm total, and most piezometers at about 18 m depth remained dry. In this area, at this time, recharge appears to be negligible due to low

  20. Implications of deep drainage through saline clay for groundwater recharge and sustainable cropping in a semi-arid catchment, Australia

    Science.gov (United States)

    Timms, W. A.; Young, R. R.; Huth, N.

    2012-04-01

    The magnitude and timing of deep drainage and salt leaching through clay soils is a critical issue for dryland agriculture in semi-arid regions (2000 mm yr-1) such as parts of Australia's Murray-Darling Basin (MDB). In this rare study, hydrogeological measurements and estimations of the historic water balance of crops grown on overlying Grey Vertosols were combined to estimate the contribution of deep drainage below crop roots to recharge and salinization of shallow groundwater. Soil sampling at two sites on the alluvial flood plain of the Lower Namoi catchment revealed significant peaks in chloride concentrations at 0.8-1.2 m depth under perennial vegetation and at 2.0-2.5 m depth under continuous cropping indicating deep drainage and salt leaching since conversion to cropping. Total salt loads of 91-229 t ha-1 NaCl equivalent were measured for perennial vegetation and cropping, with salinity to ≥ 10 m depth that was not detected by shallow soil surveys. Groundwater salinity varied spatially from 910 to 2430 mS m-1 at 21 to 37 m depth (N = 5), whereas deeper groundwater was less saline (290 mS m-1) with use restricted to livestock and rural domestic supplies in this area. The Agricultural Production Systems Simulator (APSIM) software package predicted deep drainage of 3.3-9.5 mm yr-1 (0.7-2.1% rainfall) based on site records of grain yields, rainfall, salt leaching and soil properties. Predicted deep drainage was highly episodic, dependent on rainfall and antecedent soil water content, and over a 39 yr period was restricted mainly to the record wet winter of 1998. During the study period, groundwater levels were unresponsive to major rainfall events (70 and 190 mm total), and most piezometers at about 18 m depth remained dry. In this area, at this time, recharge appears to be negligible due to low rainfall and large potential evapotranspiration, transient hydrological conditions after changes in land use and a thick clay dominated vadose zone. This is in