72 resultados para mercuric nitrate


Relevância:

10.00% 10.00%

Publicador:

Resumo:

This is the Cheshire Meres 1995, May – June Surveys Report from the National Rivers Authority, 1995. The report focuses on the surveys of ten Cheshire Meres in November 1994 and then again in May-June 1995 as part of a rolling program examining the water quality of this group of still waters. The ten meres surveyed were: Betley, Budworth, Combermere, Hatchmere, Oak mere, Pick mere, Redes, Rostheme, Tabley, and Tatton. This report discusses the results of the May-June survey before making a comparison between these and the November survey results. The section on results contains information about suspended solids (S.S.) and volatile suspended solids (V.S.S.); Nitrate and Nitrite; Ammonia; ortho-Phosphate; Silicate and Soluble reactive Silica; and total Phosphorus.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This is the South Area still waters 1995 November surveys from the National Rivers Authority, 1996. The report focuses on the surveys of ten Cheshire Meres (Betley, Budworth, Combermere, Hatchmere, Oak mere, Pick mere, Redes, Rostherne, Tabley, and Tatton) previously surveyed in November 1994 and May 1995. Eight others (Chapel Mere, Little Mere, Marbury Mere, Mere Mere, Oss Mere, Petty Pool, Quoisley Big Mere and Tabley Moat) were surveyed for the first time. Two other lakes, Carr Mill Dam and Pennington Flash, were surveyed. Neither of these are considered to be part of the Cheshire meres group of lakes but are of a Regional interest. This report discusses the results of the November 1995 survey before making a comparison between these and the November 1994 survey results. The section on results contains information about water column profile; nutrients (chlorophyll a; Phaeophytin; Nitrate and Nitrite; Ammonia; ortho-Phosphate; Silicate; and total Phosphorus.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This is the Cheshire stillwaters. Summary results of September 1998 from the Environment Agency, 1998. In May 1997, a Stillwaters meeting was held to discuss the way forward in stillwaters monitoring. It decided upon the establishment of a three year rolling programme, in which three stillwaters would be monitored three times a year, every third year. Oak Mere, Tatton Park Mere and Hatch Mere were surveyed between the 29th - 30th September as part of the three year rolling programme. Betley Mere, Petty Pool, Scotman's Flash and Pearson's Flash were also surveyed. Surveys also included algal and zooplankton samples, which are to be analysed by APEM and presented in the end of year report. The section on results contains information about water column profile; and nutrients (chlorophyll a; Phaeophytin; Nitrate and Nitrite; Ammonia; ortho-Phosphate; Silicate; and total Phosphorus).

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This is the Oak Mere continuous monitoring summary report, 1997 to 2000 from the Environment Agency North West. This report focuses on the continuous monitoring programme made by a multi -parameter probe in Oak Mere since summer 1997. From 1999 nutrient and chlorophyll samples were taken when the water quality instrument was serviced. Water level measurements were made since 1998. Moreover, the report shows a summary Oak mere water quality of each year (1997-2000). The physico-chemical parameters and nutrient levels included are: temperature, specific conditions, dissolved oxygen, pH, Depth, secchi disc measurements, chlorophyll a, total Phosphorus, orto-Phosphate, Nitrate, Ammonia, and Silicate.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This is the Cheshire Meres 1994 November surveys report produced by the National Rivers Authority in 1995. The report focuses on some of Cheshire meres, which were showing evidence of increasing eutrophication, commonly due to anthropogenic inputs. Concern for the deterioration of the water quality of still waters has been translated by incorporating these priorities into the NRA North West Regional Environmental Strategy for Stillwaters. The meres were also being investigated as possible polluted waters under the EC Nitrate Directive. The ultimate aim is to formulate lakes management options in order to help preserve North West still waters and minimise future restoration programmes. For such pro-active work to be carried out, sufficient background data must be available. It should then be possible to fully assess the current status of these lakes, identify seasonal trends and detect significant point/diffuse pollution inputs. These surveys were the first of a series, and it was intended to repeat similar surveys in Summer and Autumn 1995, and include a further 20 meres.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This is a report on the Analysis of Data and a Prioritisation of Sites at the Cheshire Meres by the Institute of Freshwater Ecology. The report addresses data collected by the Agency for 24 basin sites in Cheshire. At least two samples were collected from each site, though not simultaneously. Sites were visited in May/June and in November. The determinands are standard and they included: water, temperature, conductivity, pH, DO, fractional white light penetration, TSS, chlorophyll, TP, ortho-phosphate, nitrate-, nitrite-, ammonium and silicate. Though concentrations were often higher than for other lakes in the region, rather exceeding criteria for classification as eutrophic lakes, the results confirmed that the series of lakes is, naturally, highly eutrophic and nothing in the present data differs so far from expectation that is persuasive that the ecosystems are reacting adversely to environmental stress. The data set is review and summarised, site-by-site, in an appendix. The grounds for prioritisation are discussed. Whether or not this preferred prioritised option is adopted, the Agency is recommended to review the way it carries out monitoring. The determinands and the sampling frequency need to be geared to the information that is required.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This is the Limnological survey of the Cheshire, Shropshire, and Staffordshire Meres: Interim data report produced by the University of Liverpool in 1992. This report looks at the Limnological survey data from Cheshire, Shropshire and Staffordshire Meres. Limnological data of the report covers: changes in water conductivity, Phenolphthalein Alkalinity, Total Alkalinity, pH, Chloride concentrations, Soluble reactive Phosphorus, Total Phosphorus, Nitrate Nitrogen, Ammonium Nitrogen, Silicate, Chlorophyll, Carotenoids, Secci disk depth, changes in Trophic Score, changes in DAFOR scores for submerged and floating plants and Oxygen saturation during summer. This report also contains Seasonal maps of different Meres. The more important limnological data are plotted as seasonal means in relation to the sampling sites. Conductivity is shown as μSiemens per cm, alkalinity as milliequivalents per litre. Total and soluble reactive (available inorganic) phosphorus are shown in terms of P in μg per litre. Nitrate and ammonium are shown in terms of N in mg per litre. Chlorophyll a is given as μg per litre. A profile of oxygen saturation is shown. These profiles were obtained towards the middle of the day in August and September.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This is the Kent estuary survey 18th July 1981 produced by the North West Water Authority in 1981. The report focuses on a tidal cycle survey carried out on the Kent estuary on the 18th August, 1981. The chemical water quality at Arnside Pier and at New Barns was, on the whole, acceptable. However, samples taken downstream of the outfall at low water for total coliforms and E. coli were all above the EEC mandatory level whilst those for faecal streptococci were all above the guideline value. This document shows chemical and bacteriological data analysed at Kent estuary such chloride, dissolved oxygen, BOD, ammonia, nitrate, phosphate, total coliforms, E. coli and Faecal streptococci.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This is the Kent estuary 1992 surveys: Summary of results produced by the National Rivers Authority in 1993. The report summarises routine and baseline water quality surveys carried out on the Kent estuary during 1992. Baseline surveys are designed to respond to regional, national, and European requirements. During 1992 baseline surveys were carried out in June and December. Unfortunately, in June, samples could only be taken from stations 3, 7 and 8. For ease of interpretation the results have been presented in graph form, including the maximum and minimum parameter concentration and the appropriate Environmental Quality Standards (EQS). The parameters measured in this survey were physical parameters (temperature, BOD, dissolved oxygen, Ph, salinity, conductivity); nutrients (ammonia, phosphate, and nitrate); metals (Mercury, Nickel, Arsenic, Cadmium, Chromium, Cooper, Boron, and Zinc) and organic compounds.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Two large hydrologic issues face the Kings Basin, severe and chronic overdraft of about 0.16M ac-ft annually, and flood risks along the Kings River and the downstream San Joaquin River. Since 1983, these floods have caused over $1B in damage in today’s dollars. Capturing flood flows of sufficient volume could help address these two pressing issues which are relevant to many regions of the Central Valley and will only be exacerbated with climate change. However, the Kings River has high variability associated with flow magnitudes which suggests that standard engineering approaches and acquisition of sufficient acreage through purchase and easements to capture and recharge flood waters would not be cost effective. An alternative approach investigated in this study, termed On-Farm Flood Flow Capture, involved leveraging large areas of private farmland to capture flood flows for both direct and in lieu recharge. This study investigated the technical and logistical feasibility of best management practices (BMPs) associated with On-Farm Flood Flow Capture. The investigation was conducted near Helm, CA, about 20 miles west of Fresno, CA. The experimental design identified a coordinated plan to determine infiltration rates for different soil series and different crops; develop a water budget for water applied throughout the program and estimate direct and in lieu recharge; provide a preliminary assessment of potential water quality impacts; assess logistical issues associated with implementation; and provide an economic summary of the program. At check locations, we measured average infiltration rates of 4.2 in/d for all fields and noted that infiltration rates decreased asymptotically over time to about 2 – 2.5 in/d. Rates did not differ significantly between the different crops and soils tested, but were found to be about an order of magnitude higher in one field. At a 2.5 in/d infiltration rate, 100 acres are required to infiltrate 10 CFS of captured flood flows. Water quality of applied flood flows from the Kings River had concentrations of COC (constituents of concern; i.e. nitrate, electrical conductivity or EC, phosphate, ammonium, total dissolved solids or TDS) one order of magnitude or more lower than for pumped groundwater at Terranova Ranch and similarly for a broader survey of regional groundwater. Applied flood flows flushed the root zone and upper vadose zone of nitrate and salts, leading to much lower EC and nitrate concentrations to a depth of 8 feet when compared to fields in which more limited flood flows were applied or for which drip irrigation with groundwater was the sole water source. In demonstrating this technology on the farm, approximately 3,100 ac-ft was diverted, primarily from April through mid-July, with about 70% towards in lieu and 30% towards direct recharge. Substantial flood flow volumes were applied to alfalfa, wine grapes and pistachio fields. A subset of those fields, primarily wine grapes and pistachios, were used primarily to demonstrate direct recharge. For those fields about 50 – 75% of water applied was calculated going to direct recharge. Data from the check studies suggests more flood flows could have been applied and infiltrated, effectively driving up the amount of water towards direct recharge. Costs to capture flood flows for in lieu and direct recharge for this project were low compared to recharge costs for other nearby systems and in comparison to irrigating with groundwater. Moreover, the potentially high flood capture capacity of this project suggests significant flood avoidance costs savings to downstream communities along the Kings and San Joaquin Rivers. Our analyses for Terranova Ranch suggest that allocating 25% or more flood flow water towards in lieu recharge and the rest toward direct recharge will result in an economically sustainable recharge approach paid through savings from reduced groundwater pumping. Two important issues need further consideration. First, these practices are likely to leach legacy salts and nitrates from the unsaturated zone into groundwater. We develop a conceptual model of EC movement through the unsaturated zone and estimated through mass balance calculations that approximately 10 kilograms per square meter of salts will be flushed into the groundwater through displacing 12 cubic meters per square meter of unsaturated zone pore water. This flux would increase groundwater salinity but an equivalent amount of water added subsequently is predicted as needed to return to current groundwater salinity levels. All subsequent flood flow capture and recharge is expected to further decrease groundwater salinity levels. Second, the project identified important farm-scale logistical issues including irrigator training; developing cropping plans to integrate farming and recharge activities; upgrading conveyance; and quantifying results. Regional logistical issues also exist related to conveyance, integration with agricultural management, economics, required acreage and Operation and Maintenance (O&M).

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Dinoflagellates possess many physiological processes that appear to be under post-transcriptional control. However, the extent to which their genes are regulated post-transcriptionally remains unresolved. To gain insight into the roles of differential mRNA stability and de novo transcription in dinoflagellates, we biosynthetically labeled RNA with 4-thiouracil to isolate newly transcribed and pre-existing RNA pools in Karenia brevis. These isolated fractions were then used for analysis of global mRNA stability and de novo transcription by hybridization to a K. brevis microarray. Global K. brevis mRNA half-lives were calculated from the ratio of newly transcribed to pre-existing RNA for 7086 array features using the online software HALO (Half-life Organizer). Overall, mRNA half-lives were substantially longer than reported in other organisms studied at the global level, ranging from 42 minutes to greater than 144 h, with a median of 33 hours. Consistent with well-documented trends observed in other organisms, housekeeping processes, including energy metabolism and transport, were significantly enriched in the most highly stable messages. Shorter-lived transcripts included a higher proportion of transcriptional regulation, stress response, and other response/regulatory processes. One such family of proteins involved in post-transcriptional regulation in chloroplasts and mitochondria, the pentatricopeptide repeat (PPR) proteins, had dramatically shorter half-lives when compared to the arrayed transcriptome. As transcript abundances for PPR proteins were previously observed to rapidly increase in response to nutrient addition, we queried the newly synthesized RNA pools at 1 and 4 h following nitrate addition to N-depleted cultures. Transcriptome-wide there was little evidence of increases in the rate of de novo transcription during the first 4 h, relative to that in N-depleted cells, and no evidence for increased PPR protein transcription. These results lend support to the growing consensus of post-transcriptional control of gene expression in dinoflagellates.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This study assessed the physico-chemical quality of River Ogun, Abeokuta, Ogun state, Southwestern Nigeria. Four locations were chosen spatially along the water course to reflect a consideration of all possible human activities that are capable of changing the quality of river water. The water samples were collected monthly for seven consecutive months (December 2011 – June 2012) at the four sampling stations. pH, air temperature (℃), water temperature (℃), conductivity (µs/cm) and total dissolved solids (mg/L) were conducted in-situ with the use of HANNA Combo pH and EC multi meter Hi 98129 and Mercury-in-glass thermometer while dissolved oxygen (mg/L), nitrate (mg/L), phosphate (mg/L), alkalinity (mg/L) and hardness (mg/L) were determined ex-situ using standard methods. Results showed that dissolved oxygen, hydrogen ion concentration, total hardness and nitrate were above the maximum permissible limit of National Administration for Food, Drugs and Control (NAFDAC), Standard Organization of Nigeria (SON), Federal Environmental Protection Agency (FEPA), United States Environmental Protection Agency (USEPA), European Union (EU) and World Health Organization (WHO) for drinking water during certain months of the study period. Results also showed that water temperature and conductivity were within the permissible limits of all the standards excluding FEPA. However, total dissolved solids and alkalinity were within the permissible limits of all the standards. Adejuwon and Adelakun, (2012) also reported similar findings on Rivers Lala, Yobo and Agodo in Ewekoro local government area of Ogun state, Nigeria. Since most of the parameters measured were above the maximum permissible limits of the national and international standards, it can be concluded that the water is unfit for domestic uses, drinking and aquacultural purposes and therefore needs to be treated if it is to be used at all. The low dissolved oxygen values for the first four months was too low i.e. < 5 mg/L. This is most likely as a result of the amount of effluents discharged into the river. To prevent mass extinction of aquatic organisms due to anoxic conditions, proper regulations should be implemented to reduce the organic load the river receives.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Water quality of three stations representing polluted (Sts. B & S) and relatively unpolluted (St. M) areas along the coast of Bombay was studied during Mar 1981 to May 1982. Stations B & S were characterized by relatively wider fluctuations in salinity, low range of dissolved oxygen and higher BOD, phosphate and nitrate levels. At St. M higher range of dissolved oxygen coupled with low values of BOD and nutrients suggest the prevailing good water quality. The deteriorating water quality of the polluted station probably lead to retarded growth of Saccostrea cucullata and Cerithium rubus living in the shallow intertidal region.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Nitrogen and phosphorus requirements of a chain-forming diatom, Skeletonema costatum (Greville) Cleve, collected from Yatsushiro Sea, Japan, were investigated in a laboratory culture experiment. Sodium nitrate and sodium glycerophosphate were used as nitrogen and phosphorus sources, respectively. Cultures were grown in modified Provasoli's ASP2NTA medium (Provasoli et al. 1957) at 25±1°C, light intensity 60 µE mˉ² secˉ¹ and photoperiod 12:12-h, L:D cycle. Optimum growth was observed at nitrate concentrations of 3-10 mglˉ¹ and phosphate concentrations of 1.5-15 mglˉ¹. Adequate growth was also found at the nitrate concentration of up to as high as 300 mglˉ¹. Significantly poorer growth was found at lower nitrate (<3.0 mglˉ¹) and higher phosphate (>15 mglˉ¹) concentrations. From the present study, it is concluded that S. costatum can grow well at wide ranges of nitrate concentrations but is sensitive to higher phosphate concentrations.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

An experiment was conducted in farmers’ fields under Paikgacha thana, Khulna to study the suitability of integrated rice-cum-fish culture. Three treatments namely T1 (Puntius gonionotus), T2 (Puntius gonionotus and Cyprinus carpio) and T3 ( Cyprinus carpio) were included for the study each having three replicates. The fish were stocked at a density of 3750/ha in all the rice plots. The physicochemical parameters of water viz., water depth, temperature, dissolved oxygen, pH, salinity, nitrate and phosphate etc. recorded during the study period were found within optimum range. Of the two cultured species C. carpio attained the highest average individual weight (160g) and survival (81.06%). With respect to biomass and income, highest average fish production and net profit per hectare (306.74kg and Tk. 8177.91) were obtained in T2 and the lowest (184.17kg and Tk. 2049.41) obtained in T1 and a significant variation (p<0.05) in fish production was observed among the treatments while for rice production, it was insignificant. The cost benefit ratio of fish production found were 1:1.29, 1:2.14 and 1:1.90 for T1, T2 and T3, respectively.