Ditch Water Research Articles

Biological Control of <I>Culex quinquefasciatus</I> Say (Diptera: Culicidae) Larvae

Local larvivorous fish <em>Aphanius dispar</em> has potential for regulating vector mosquitoes. The consumption of larvae of the mosquito <em>Culex quinquefasciatus</em> Say (Diptera: Culicidae) by <em>Rasbora daniconius, Puntius ticto</em> and <em>Puntius conchonius</em> was evaluated in the presence of different prey densities under simple habitat conditions. The number of mosquito larvae consumed in fresh and ditch water at three seasons was observed. Only third and fourth instars of Culex larvae were used on a particular prey density of 1 to 10 (increase 100). The maximum and minimum value of larvae eating per day in ditch and fresh water were observed to 267 to 876 and 277 to 880 respectively. The comparisons for the pair using Tukey-Kramer HSD indicated the fact that there was non-significant difference. The respective mean values in fresh and ditch water were observed 525 and 493 respectively. The analysis of water (ditch and fresh) was nonsignificant (F = 1.0116). <em>Rasbora daniconius</em> species of fish played a dominating role in eating the <em>Culex</em> larvae in ditch and fresh water.

Quality of shallow groundwater and manure effluents in a livestock farm

Abstract The aim of the study was to assess the quality of shallow groundwater on the site pens and runoff from livestock manure heaps, in three selected farms involved in animal production and vegetable crops in the area of Plateau Proszowice. The analysis mainly included water from farm wells and effluents from manure. Additionally, water from drainage ditch running nearby farms was collected, before inflow of effluent (i.e. ditch water without manure effluent) and below inflow of effluent from heap of manure (i.e. ditch water containing manure effluent). Samples of the research material were collected from April 2012 to March 2014 at monthly intervals and analysed for the content of NO3-N, NH4-N, PO4-P, K, Na and Cl. Based on the obtained results it was found that water from the farm wells near the livestock buildings and from manure storage sites, was heavily polluted by the majority of these contaminants. The highest concentration of these pollutants, except for the NO3-N, was found in manure effluent – it exceeded a few dozen to a few hundred to any standards for water quality. There was also a significant deterioration in the quality of drainage ditch water because of the penetration of contaminants into ditch water from heaps of improperly stored manure. The water of the farm wells was characterized by excessive concentrations of NO3-N which disqualified it for drinking purposes.

Purification efficiency of nitrogen and phosphorus in Ottelia acuminata on four kinds of simulated sewage

Erhai Lake is mainly composed of low-pollution river water, farmland return water, village farmland mixed sewage, and village ditch water. The study of whether Ottelia can adapt to these four types of sewage and clean the water not only can clarify the resistance of Ottelia to contamination but also has good application value. Ottelia was experimentally cultivated in simulated sewage through artificial water distribution according to the characteristics of nitrogen and phosphorus in the four kinds of sewage. The changes in the nitrogen and phosphorus contents in water and Ottelia were determined. The adaptation of Ottelia to these four kinds of sewage, as well as the nitrogen and phosphorus purification efficiencies, was studied. Results showed that Ottelia could survive in simulated farmland return water, low-pollution river water (Yongan River) and village farmland mixed sewage. The nutrients in water influenced the flowering behavior of Ottelia. The maximum average total phosphorus and ammonia nitrogen removal rates of 29.88% and 32.4%, respectively, in Ottelia were found in the low-pollution river group. The average total nitrogen removal rate in the farmland return water group was the highest at 31.29%. Considering the removal rate, total removed volume, and Ottelia growth, the efficiency of applying Ottelia in the treatment of farmland return water around Erhai Lake was the highest. Moreover, the optimal hydraulic retention time should be 4 days when Ottelia is applied for the treatment of farmland return water from constructed wetlands.

Impacts of forest harvesting on mobilization of Hg and MeHg in drained peatland forests on black schist or felsic bedrock.

Forest harvesting, especially when intensified harvesting method as whole-tree harvesting with stump lifting (WTHs) are used, may increase mercury (Hg) and methylmercury (MeHg) leaching to recipient water courses. The effect can be enhanced if the underlying bedrock and overburden soil contain Hg. The impact of stem-only harvesting (SOH) and WTHs on the concentrations of Hg and MeHg as well as several other variables in the ditch water was studied using a paired catchment approach in eight drained peatland-dominated catchments in Finland (2008-2012). Four of the catchments were on felsic bedrock and four on black schist bedrock containing heavy metals. Although both Hg and MeHg concentrations increased after harvesting in all treated sites according to the randomized intervention analyses (RIAs), there was only a weak indication of a harvest-induced mobilization of Hg and MeHg into the ditches. Furthermore, no clear differences between WTHs and SOH were found, although MeHg showed a nearly significant difference (p = 0.06) between the harvesting regimes. However, there was a clear bedrock effect, since the MeHg concentrations in the ditch water were higher at catchments on black schist than at those on felsic bedrock. The pH, suspended solid matter (SSM), dissolved organic carbon (DOC), and iron (Fe) concentrations increased after harvest while the sulfate (SO4-S) concentration decreased. The highest abundances of sulfate-reducing bacteria (SRB) were found on the sites with high MeHg concentrations. The biggest changes in ditch water concentrations occurred first 2years after harvesting.

Modeling the Impact of Ditch Water Level Management on Stream–Aquifer Interactions

Decreasing groundwater levels in many parts of Germany and decreasing low flows in Central Europe have created a need for adaptation measures to stabilize the water balance and to increase low flows. The objective of our study was to estimate the impact of ditch water level management on stream-aquifer interactions in small lowland catchments of the mid-latitudes. The water balance of a ditch-irrigated area and fluxes between the subsurface and the adjacent stream were modeled for three runoff recession periods using the Hydrus-2D software package. The results showed that the subsurface flow to the stream was closely related to the difference between the water level in the ditch system and the stream. Evapotranspiration during the growing season additionally reduced base flow. It was crucial to stop irrigation during a recession period to decrease water withdrawal from the stream and enhance the base flow by draining the irrigated area. Mean fluxes to the stream were between 0.04 and 0.64 ls−1 for the first 20 days of the low-flow periods. This only slightly increased the flow in the stream, whose mean was 57 ls−1 during the period with the lowest flows. Larger areas would be necessary to effectively increase flows in mesoscale catchments.

Removal of fluoroquinolone contaminants from environmental waters on sepiolite and its photo-induced regeneration

Sepiolite is studied as sorbent for removal of Fluoroquinolone (FQ) contaminants from water. Marbofloxacin (MAR) and Enrofloxacin (ENR) were chosen as model FQs since they are the two most commonly employed veterinary FQs in livestock farming in northern Italy. Adsorption experiments on two sepiolites (SP-1 and SSE16) were carried out in tap water at pH 7.5 to better mimic real conditions. The sorption experimental data were fitted by Freundlich, Langmuir and S-Logistic1 models. The latter better described MAR and ENR adsorptions. Adsorption capacities of SP-1 and SSE16, respectively, were 132 mg g−1 and 121 mg g−1 for MAR, and 112 mg g−1 and 93 mg g−1 for ENR. X-ray powder diffraction, performed on clay samples enriched with each FQ and on the pristine clays, showed no substantial differences between the two sepiolites and evidenced no significant structural changes after FQs uptake, as also verified by infrared spectroscopy. This indicates that adsorption occurs only on the external surface of the mineral and not in the intracrystalline microporosity, likely due to the interaction between the FQ carboxylic group and the sepiolite surface. For the first time solid-state photodegradation of the adsorbed FQs was investigated for regenerating the sorbent. Results showed that the adsorbed drugs are effectively photodegraded by solar light, thus allowing sepiolite to be reused. The efficiency of this material for remediation of contaminated water was proved on ditch water, collected downstream a swine farm, containing some tens of ng L−1 of MAR and ENR.

Metal Distribution and Contamination Assessment in Drainage Ditch Water in the Main Rice/Vegetable Area of Sichuan Hilly Basin.

In order to assess the impact of four land use changes on metal concentrations in the hilly Sichuan Basin of China, 71 surface water samples were collected in July and November 2014. Samples from residential ditch water were found to have higher metal concentrations than those in other types of ditches, while the lowest occurred in barren land ditch water. However, the selected metals were below the Chinese surface water quality standards and WHO (2011). The pollution index of four determined land use types was also below the critical pollution index, suggesting there were low levels of pollution in Sichuan Basin. Arsenic was the most important pollutant of concern. Results indicate steps should be taken to control and reduce the risk of metals released from residential ditch water.

The fate of fusion Cry1Ab/1Ac proteins from Bt-transgenic rice in soil and water

Toxin proteins form transgenic crops entering into the environment are likely affect non-target organisms. To investigate the entry route and fate of fusion Cry1Ab/1Ac proteins from transgenic rice expressing insecticide toxins from Bacillus thuringiensis (Bt) in soil and water, we conducted greenhouse and field experiments in 2013 and 2014. Cry1Ab/1Ac proteins from Bt-transgenic rice in soil was found within a horizontal range of 25cm, where most of plant roots distributed. Concentration of Cry1Ab/1Ac proteins was lower in water than in soil in the greenhouse experiment, and no Cry1Ab/1Ac protein was detected in field water. Cry1Ab/1Ac concentration from rice straws was higher in ditch water than in distilled water due to the existence of aquatic organisms in ditch water. Bt proteins from transgenic crops enter into soil ecosystems mainly through root exudates and into aquatic ecosystems through plant residues, which determines Bt fate in the environment.

Effects of temperature, rainfall and conifer felling practices on the surface water chemistry of northern peatlands

Afforested peatlands account for about 25 % of human-affected peatlands worldwide. In some regions, particularly the British Isles, forest-to-bog conversions are now underway in the hope of increasing carbon storage and restoring original ecosystem functions. In this study, the effects on surface water quality of forest-to-bog restoration in the Flow Country peatlands of northern Scotland were monitored during 15 months. The hydrochemistry of rainwater, resurgence ground water, forestry drainage ditch water, open bog surface water, forestry-influenced loch water and stream water was examined before, during and after felling. The seasonal cycles of biologically active (C, Si, P) and organically complexed (Fe, Al) elements were characterised by major changes in concentration. The felling operations amplified these effects due to (i) the decomposition of felling residues (leaching K and C) and (ii) the disturbance and partial mineralisation of shallow peat soils (releasing P, Fe and Al). Shorter term changes (1–10 days) produced by rainfall events and associated changes in hydrological flow paths controlled the concentrations of Na, Ca, Mg, Mn, and to a lesser extent K and Al. There were significant negative correlations with flow of [K], [Ca] and [Mg] but a positive correlation between stream flow and [Al]. Concentration-flow relationships were not significantly altered by the felling operations because of the relatively low volume of water released from the felled area. Fluctuations in the water table represented another important control of surface water composition. Resurgence waters produced high [Fe] and [Si] values when water table levels were low. These contributions were diluted with runoff and surface soil waters enriched in dissolved organic carbon (DOC) when levels rose. Sequential ultrafiltration revealed that Fe, C and P co-occurred in the >30 kDa molecular weight fraction in constant relative concentrations. Since forest-to-bog restoration raises the water table, it can be anticipated to result initially in more intense flushing of DOC, including the >30 kDa molecular weight fraction where Fe and P co-occur.

Enhancing the Biodiversity of Ditches in Intensively Managed UK Farmland.

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 biodiversity value of ditches, and improve their ecosystem service delivery, management prescriptions for hedgerows adjacent to ditches should differ from those aimed at hedgerows only.

Accumulation of steroid hormones in soil and its adjacent aquatic environment from a typical intensive vegetable cultivation of North China

Steroid hormones released from manure agricultural application are a matter of global concern. The residual levels of steroid hormones were studied in a typical intensive vegetable cultivation area in northeast China, with a long history of heavy manure application. Seven steroids (estrone, 17α-estradiol, 17β-estradiol, estriol, testosterone, androstendione and progesterone) were analyzed from soil sampled from vegetable greenhouses, from sediments and water from the adjacent drainage ditch and from the groundwater. The results showed that target steroids were detected in the soil samples, with detection frequencies varying from 3.13 to 100%. The steroid concentrations varied substantially in soils, ranging from below the detection limit to 109.7μg·kg−1. Three steroids—progesterone, androstendione and estrone—were found to have relatively high residue concentrations in soil, with maximum concentrations of 109.7, 9.83 and 13.30μg·kg−1, respectively. In adjacent groundwater, all the steroids, with the exception of estrone, were detected in one or more of the 13 groundwater samples. The concentrations of steroids in groundwater ranged from below the method detection limit to 2.38ng·L−1. Six of the seven (excluding androstendione) were detected in drainage ditch water samples, with concentrations ranging from below the detection limit to 14ng·L−1. Progesterone, androstendione and estrone accumulated relatively easily in soils; their concentrations in groundwater were lower than those of other steroids. The concentrations of testosterone and estriol were relatively low in soil, while in groundwater were higher than those of other steroids. The residual levels of steroids in soil and groundwater showed a clear spatial variation in the study area. The residual levels of steroid hormones in soil varied substantially between differently planted greenhouses.

A Study of Equivalent Manhole in Streets-Sewers of Urban District Instead of Roadside Water Exchange by the SWMM Model

The important flooding drainage phenomenon of the urban regions includes of ground water exchange, sewer water exchange and ground-sewer water exchange. Due to the spread of urban regions development with high economics activities, the distributions and specifications of ditch in urban regions are irregular and un-uniform, equivalent Manhole would be used instead of ditch water exchange and its mechanism to fill ground water and sewer water exchange mode evaluated for urban flooding mode in this study. Sewer’s catchment of Ming-Seng S. Rd 608 Street in Chiayi City as case study applied by SWMM model showing urban flooding phenomenon and the effective drainage mechanism during rainfall similar Typhoon Morakot, thus, providing reliable information and references for engineers.

Subsoil Phosphorus Loss: A complex problem with no easy solutions

Subsoil Phosphorus Loss: A complex problem with no easy solutions

Phosphorus losses from agricultural land to natural waters are reduced by immobilization in iron-rich sediments of drainage ditches

Redox reactions involving iron (Fe) strongly affect the mobility of phosphorus (P) and its migration from agricultural land to freshwater. We studied the transfer of P from groundwater to open drainage ditches in an area where, due to Fe(II) rich groundwater, the sediments of these ditches contain accumulated Fe oxyhydroxides. The average P concentrations in the groundwater feeding two out of three studied drainage ditches exceeded environmental limits for freshwaters by factors 11 and 16, but after passing through the Fe-rich sediments, the P concentrations in the ditch water were below these limits. In order to identify the processes which govern Fe and P mobility in these systems, we used diffusive equilibration in thin films (DET) to measure the vertical concentration profiles of P and Fe in the sediment pore water and in the ditchwater. The Fe concentrations in the sediment pore water ranged between 10 and 200 mg L−1 and exceeded those in the inflowing groundwater by approximately one order of magnitude, due to reductive dissolution of Fe oxyhydroxides in the sediment. The dissolved P concentrations only marginally increased between groundwater and sediment pore water. In the poorly mixed ditchwater, the dissolved Fe concentrations decreased towards the water surface due to oxidative precipitation of fresh Fe oxyhydroxides, and the P concentrations decreased more sharply than those of Fe. These observations support the view that the dynamics of Fe and P are governed by reduction reactions in the sediment and by oxidation reactions in the ditchwater. In the sediment, reductive dissolution of P-containing Fe oxyhydroxides causes more efficient solubilization of Fe than of P, likely because P is buffered by adsorption on residual Fe oxyhydroxides. Conversely, in the ditchwater, oxidative precipitation causes more efficient immobilization of P than of Fe, due to ferric phosphate formation. The combination of these processes yields a natural and highly efficient sink for P. It is concluded that, in Fe-rich systems, the fate of P at the sediment–water interface is determined by reduction and oxidation of Fe.

Calliergon megalophyllum rediscovered in the Netherlands after 50 years: comparison to Swedish habitats

The moss Calliergon megalophyllum is rediscovered in the Netherlands after approximately 50 years of absence, in a location different from before: National Park Weerribben-Wieden. This is a Natura 2000 wetland area, and a Dutch hotspot for rich-fen bryophytes. The species was growing in a fen pool. Plant species composition and water chemistry were compared with Swedish samples collected throughout the country. Water chemistry of C. megalophyllum in Sweden was also compared with four other (semi-)aquatic species: C. giganteum, Scorpidium scorpioides, Sarmentypnum trichophyllum and S. exannulatum. The species is characteristic for poorly buffered habitats, but has nevertheless relatively high pH, which makes it sensitive to acidification, especially when atmospheric deposition is high. In the Dutch locality, buffer capacity is maintained by input of base-rich ditch water through small channels in the fen. The data further suggest that, like other Calliergon species, C. megalophyllum is growing in relatively nutrient-rich habitats, especially with respect to P and K. In the Netherlands, plant nutrient concentrations suggest that P is indeed not limiting, which may enhance survival of the species, as P-poor habitats in this country have become very rare.

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

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.

The effects of long-term drainage and subsequent restoration on water table level and pore water chemistry in boreal peatlands

Degradation by drainage threatens biodiversity and globally important peatland ecosystem functions such as long-term carbon sequestration in peat. Restoration aims at safeguarding peatland values by recovering natural hydrology. Long-term effects of drainage and subsequent restoration, especially related to within-site variation of water table level and pore water chemistry, are poorly known. We studied hydrological variation at 38 boreal Sphagnum peatland sites (pristine, drained and restored) in Finland. The average water table level was significantly lower at Drained than Pristine sites especially near the ditches. We also observed large pore water chemical differences between Drained and Pristine sites, such as higher DOC concentration at the sites drained several decades earlier. Furthermore, there were large differences in water chemistry between the samples collected from ditches and from the peat strips between the ditches. For example, the ditch water had apparently higher minerogenic influence, while DOC concentrations were highest in peat strips. The water table level was, on average, at the targeted level of Pristine sites at 5 years ago restored (Res 5) and 10 years ago restored (Res 10) sites. The Res 10 sites were more similar to the Pristine sites in water chemical composition than were the Drained sites. Water chemical differences between ditches and peat strips were smaller at the Res 5 and Res 10 than at Drained sites indicating, on average, successful decrease of drainage-induced within-site variation in water chemistry. Our results suggest more pronounced water table inclination towards the old ditches at Res 10 than at Res 5 sites. While this pattern may be an early warning sign for incomplete recovery of hydrology in long-term, we found no chemical evidence supporting this assumption yet. Our study suggests that restoration can result in significant recovery of peatland hydrology within 10 years, while some deviation from pristine hydrology is still typical. Restoration appears to have potential to reduce leaching of nutrients and DOC to downstream waters in the long term, but practitioners should be prepared for temporary increase of leaching of N and P for at least 5 years after restoration of boreal Sphagnum peatlands.

The effect of peatland drainage and rewetting (ditch blocking) on extracellular enzyme activities and water chemistry

AbstractExtensive areas of European peatlands have been drained by digging ditches in an attempt to improve the land, resulting in increased carbon dioxide fluxes to the atmosphere and enhanced fluvial dissolved organic carbon (DOC) concentrations. Numerous peatland restoration projects have been initiated which aim to raise water tables by ditch blocking, thus reversing drainage‐induced carbon losses. It has been suggested that extracellular hydrolase and phenol oxidase enzymes are partly responsible for controlling peatland carbon dynamics and that these enzymes are affected by environmental change. The aim of this study was to investigate how drainage and ditch blocking affect enzyme activities and water chemistry in a Welsh blanket bog, and to study the relationship between enzyme activity and water chemistry. A comparison of a drained and undrained site showed that the drained site had higher phenol oxidase and hydrolase activities, and lower concentrations of phenolic compounds which inhibit hydrolase enzymes. Ditch blocking had little impact upon enzyme activities; although hydrolase activities were lowered 4–9 months after restoration, the only significant difference was for arylsulphatase. Finally, we noted a negative correlation between β‐glucosidase activity and DOC concentrations, and a positive correlation between arylsulphatase activity and sulphate concentration. Phenol oxidase activity was negatively correlated with DOC concentrations in pore water, but for ditch water phenol oxidase correlated negatively with the ratio of phenolics to DOC. Our results imply that drainage could exacerbate gaseous and fluvial carbon losses and that peatland restoration may not reverse the effects, at least in the short term.

Fatal Granulomatous Amebic Encephalitis Due to Balamuthia mandrillaris in New Mexico: A Case Report.

Balamuthia mandrillaris is a free-living amoeba that can cause granulomatous amebic encephalitis (GAE). We report a case in an individual with a history of alcohol abuse, cocaine use, and ditch water exposure. This is the first reported case of GAE due to B mandrillaris in New Mexico.

Characterizing preferential groundwater discharge through boils using temperature

Summary In The Netherlands, preferential groundwater discharge trough boils is a key process in the salinization of deep polders. Previous work showed that boils also influence the temperature in the subsurface and of surface water. This paper elaborates on this process combining field observations with numerical modeling. As is the case for salinity, a distinct anomaly in the subsurface and surface water temperature can be attributed to boils. Lines of equal temperature are distorted towards the boil, which can be considered as an upconing of the temperature profile by analogy of the upconing of a fresh–saltwater interface. The zone of this distortion is limited to the immediate vicinity of the boil, being about 5 m in the aquitard which holds the boil’s conduit, or maximum a few dozens of meters in the underlying aquifer. In the aquitard, heat transport is conduction dominated whereas this is convection dominated in the aquifer. The temperature anomaly differs from the salinity anomaly by the smaller radius of influence and faster time to reach a new steady-state of the former. Boils discharge water with a temperature equal to the mean groundwater temperature. This influences the yearly and diurnal variation of ditch water temperature in the immediate vicinity of the boil importantly but also the temperature in the downstream direction. Temporary nature of the boil (e.g. stability of the conduit, discharge rate), uncertainty on the 3D construction of the conduit and heterogeneity of the subsoil make it unlikely that temperature measurements can be interpreted further than a qualitative level.