Submerged Pond Sand Filter-A Novel Approach to Rural Water Supply

DEFF Research Database (Denmark)

Øhlenschlæger, Mia; Christensen, Sarah Christine Boesgaard; Bregnhøj, Henrik

2016-01-01

This study describes the new design and function of a modified version of a traditional slow sand filter. The Submerged Pond Sand Filter is built inside a pond and has a vertical as well as a horizontal flow of water through a sloped filter opening. The filter provides treated drinking water...... to a rural Indian village. The filter has functioned with minimal maintenance for five years without being subject to the typical scraping off and changing of sand as needed in traditional slow sand filters every few months. This five-year study showed bacterial removal efficiency of 97% on average...... to 10 CFU/100 mL on average compared to shorter pumping intervals (5 min). Though the treated water did not comply with the World Health Organization standards of 0 CFU/100 mL, the filter significantly improved water quality and provided one of the best sources of drinkable water in a water...

Field Trial on Pea ( Pisum Sativum L.) Grown on Sand Soil and Subjected to Water Regimes and Nitrogen Forms with Aid of 15 N Stable Isotope

International Nuclear Information System (INIS)

Fahmy, A.E.; Abdel Aziz, H.A.; Al-Gindy, A.M.; Arafa, Y.E.

2016-01-01

A field experiment on sand soil was conducted to trace the effects of different water regimes on pea growth and nutritional values as fertilized with urea and ammonium sulfate fertilizers. 15 N/ 14 N isotope dilution technique was followed to distinguish between the different N proportions derived to pea plants and in the same time estimating the efficientuse of both two nitrogen forms (%NUE). Irrigation water regimes and fertilization treatments were applied under drip irrigation system. Two water regimes epresented 100% (W1) and 75% (W2) of water requirement in combination with three N fertilizer rates, i.e. N 0 , N 100 and N 75 were applied. Two nitrogen fertilizer forms represent urea and ammonium sulfate were performed. The overall means of seed yield as affected by nitrogen fertilization treatments reflected relative increase accounted for 45.8, and 38.7%; 41.7 and 36.2% over the unfertilized control for NU 100 , and NU 75 ; NAS 100 and NAS 75 , respectively. It seems that 100% water regime (W1) made nitrogen fertilizer, especially with high rate, more available for plant uptake comparing to the low water quantity regime. Pea crop had accumulated more nitrogen from urea comparing to ammonium sulfate fertilizer. Nitrogen uptake, in general, significantly correlated to application N rates. Water regime (W1) in combination with ammonium sulfate fertilizer resulted in the better percentage or absolute values of N derived from fertilizer by pea seeds. It was clear that efficient use of ammonium sulfate, to some extent, was affected by different wa - ter regimes. This holds true either at 100% (N1) or 75% (W2) application rates. On the other hand, urea added at rate of 75% was more efficiently used by seeds than those added at rate of 100% of the recommended N rate

Application of Self Cleaning Rapid Sand Filter in Water Treatment

Directory of Open Access Journals (Sweden)

Ali Reza Rahmani

2005-08-01

Full Text Available Rapid sand filter is one of the most important units in the water treatment plants. It has some difficulties in operation such as backwashing. For the solving of this problem a rapid sand filter has designed and built with the self-cleaning backwashing system. This system consist of 3 main constituents; one galvanized siphon and two galvanized steel tanks. One of them is used for filtration and the other used for the storage of filtrated water in elevation for backwashing the system. Water enter from upside of the filter through the inlet pipe, and collected from the under drainage pipe. Then filter water conduct to the storage tank and exit from outlet pipe. In the beginning, the head loss was low, but because of bed clogging by suspended solids, it increases gradually to the designed head loss (1.2m. Then the system is outed of the service automatically and the backwash is began. The main data for the design of system selected from the hydraulic rules of siphons and rapid sand filter criteria. After essential calculations it was constructed and was started operation. For the hydraulic studies a known volume of storage tank was selected and the time needed for the fill (in filtration stage and empty (in backwash stage of water volume with volumetric method were measured. In hydraulic studies the filter surface rate (SOR was selected about 5-7.5m3/m2/hr (1.39-2.08 lit/sec and the flow of water in siphon, during the backwashing was measured 8.7 lit/sec. It can be seen that the siphon passes 4-6 times the inlet raw water thus a negative pressure will created in the siphon which causes the water above the sand bed to be discharged automatically and rinse water from elevated tank flow under the sand bed and back wash it. So according to this study self cleaning rapid sand filter is very useful for water filtration, especially in small population community. The construction of system is rapid, simple and economic.

Band gaps and localization of surface water waves over large-scale sand waves with random fluctuations

Science.gov (United States)

Zhang, Yu; Li, Yan; Shao, Hao; Zhong, Yaozhao; Zhang, Sai; Zhao, Zongxi

2012-06-01

Band structure and wave localization are investigated for sea surface water waves over large-scale sand wave topography. Sand wave height, sand wave width, water depth, and water width between adjacent sand waves have significant impact on band gaps. Random fluctuations of sand wave height, sand wave width, and water depth induce water wave localization. However, random water width produces a perfect transmission tunnel of water waves at a certain frequency so that localization does not occur no matter how large a disorder level is applied. Together with theoretical results, the field experimental observations in the Taiwan Bank suggest band gap and wave localization as the physical mechanism of sea surface water wave propagating over natural large-scale sand waves.

Preliminary study of sand jets in water-capped artificial and real MFT

Energy Technology Data Exchange (ETDEWEB)

Cai, J.; Zhu, D.; Rajaratnam, N. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering

2008-07-01

A preliminary study of sand jets in water-capped artificial and real MFT was presented. Background information on oil sands tailing reclamation including water capping and sand capping were first discussed, followed by background information to the study, including non-Newtonian fluids and laponite clay, the artificial clay used mainly in small amounts as a rheology modifier in industrial fluids and materials. Although laponite clay is insoluble in water, it hydrates to make a clear and colourless colloidal, which is thixotropic and also behaves as a Bingham plastic fluid. The benefit of using gels made from laponite is the ability to see through to observe the physical processes in it. The objectives of the study were to examine the dynamics of sand jets in water-capped laponite gel and real MFT; improve the understanding of physical processes related to MFT and sand/slurry operations in tailings ponds; and find potential applications in recycling processed water and decommissioning of tailings ponds. It was concluded that it is much more difficult for jets to penetrate water-capped MFT due to larger yield stress in MFT. Future studies will focus on density correction, viscosity adjustment, and sensitivity analysis. tabs., figs.

Water quality and bathymetry of Sand Lake, Anchorage, Alaska

Science.gov (United States)

Donaldson, Donald E.

1976-01-01

Sand Lake, a dimictic lowland lake in Anchorage, Alaska, has recently become as urban lake. Analyses indicate that the lake is oligotrophic, having low dissolved solids and nutrient concentrations. Snowmelt runoff from an adjacent residential area, however, has a dissolved-solids concentration 10 times that of the main body of Sand Lake. Lead concentrations in the runoff exceed known values from other water in the ANchorage area, including water samples taken beneath landfills. The volume of the snowmelt runoff has not been measured. The data presented can be used as a baseline for water-resource management. (Woodard-USGS)

Microbial degradation of pesticides in rapid sand filters for treatment of drinking water

DEFF Research Database (Denmark)

Hedegaard, Mathilde Jørgensen; Albrechtsen, Hans-Jørgen

2014-01-01

In Denmark drinking water supply is based on groundwater which is treated by aeration followed by filtration in rapid sand filters. Unfortunately pesticide contamination of the groundwater poses a threat to the water supply, since the simple treatment process at the waterworks is not considered...... to remove pesticides from the water phase and pesticides are detected in 24% of the active Danish waterworks wells. This study aimed at investigating the potential of microbial pesticide removal in rapid sand filters for drinking water treatment. Removal of the pesticides MCPP, bentazone, glyphosate...... and the degradation compound p-nitrophenol was investigated in the rapid sand filters at Islevbro and Sjælsø waterworks plant I and II. Microcosms were set up with sand from rapid sand filters, water and an initial pesticide concentration of 0.03-0.38 μg/L. In all the investigated waterworks the concentration...

Watered down : overcoming federal inaction on the impact of oil sands development to water resources

International Nuclear Information System (INIS)

Droitsch, D.

2009-11-01

The oil sands industry is having a negative impact on Canada's fresh water resources and aquatic ecosystems. Members of the Government of the Northwest Territories (NT) and experts from scientific, non-governmental, and First Nations groups have stated at federal hearings that the federal government must involve itself in the protection of Canada's water resources. This report discussed compelling testimony from recent federal hearings by the House of Commons Standing Committee on Environment and Sustainable Development.The federal government must establish enforceable standards for key toxic substances created by oil sands activity. A water-sharing agreement must be established between Alberta, NT, Saskatchewan, and First Nations governments. Other recommendations included the establishment of a peer-reviewed assessment of the health impacts of industrial oil sands development on First Nations communities; the establishment of cumulative effects assessment procedures; the identification and protection of listed species at risk; and the establishment of proactive measures designed to ensure that oil sands operators pay for the environmental damage caused to water resources. 94 refs., 4 figs.

Study on Modified Sand Filtration Towards Water Quality of Wet Market Waste Water

Directory of Open Access Journals (Sweden)

Saad F.N.M.

2016-01-01

Full Text Available Investigation on the potential of sand filter as a pre-treatment of waste water was done in Kangar wet market, Perlis. Besides, the best composition of filter in order to treat wastewater based on BOD, COD, SS, AN, turbidity and pH levels are further examined. In this study, there are four types of sand filter composition which the medias consist of fine sand and coarse sand while the modified sand filter are consist of sand, course sand and activated carbon prepared from rice husk and coconut shells. After 10 weeks of treatment, the results show that the concentration of BOD, COD, SS, AN, turbidity and pH were reduced up to 86%, 84%, 63%, 88%, 73%, respectively while pH nearly to neutral with 6.83. Moreover, the result also revealed that the sand filter added with rice husk almost complied with Standard B of Malaysia Environmental Quality (Sewage Regulations 2009 as well as gives the highest number of WQI with 36.81. Overall, WQI obtained in this study are ranged from 12.77 to 36.81.

Submerged Pond Sand Filter—A Novel Approach to Rural Water Supply

Directory of Open Access Journals (Sweden)

Mia Øhlenschlæger

2016-06-01

Full Text Available This study describes the new design and function of a modified version of a traditional slow sand filter. The Submerged Pond Sand Filter is built inside a pond and has a vertical as well as a horizontal flow of water through a sloped filter opening. The filter provides treated drinking water to a rural Indian village. The filter has functioned with minimal maintenance for five years without being subject to the typical scraping off and changing of sand as needed in traditional slow sand filters every few months. This five-year study showed bacterial removal efficiency of 97% on average with a level of faecal coliforms of 2 ± 2 colony forming units (CFU/100 mL measured in the treated water. Turbidity was visibly removed during treatment. When water was retrieved from the filter through a manual pump for long consistent time intervals (60 min, faecal coliform counts increased from four to 10 CFU/100 mL on average compared to shorter pumping intervals (5 min. Though the treated water did not comply with the World Health Organization standards of 0 CFU/100 mL, the filter significantly improved water quality and provided one of the best sources of drinkable water in a water-depleted area, where only surface water was available. Furthermore, it is a sustainable treatment method due to low maintenance requirements.

The role of water content in triboelectric charging of wind-blown sand.

Science.gov (United States)

Gu, Zhaolin; Wei, Wei; Su, Junwei; Yu, Chuck Wah

2013-01-01

Triboelectric charging is common in desert sandstorms and dust devils on Earth; however, it remains poorly understood. Here we show a charging mechanism of sands with the adsorbed water on micro-porous surface in wind-blown sand based on the fact that water content is universal but usually a minor component in most particle systems. The triboelectric charging could be resulted due to the different mobility of H(+)/OH(-) between the contacting sands with a temperature difference. Computational fluid dynamics (CFD) and discrete element method (DEM) were used to demonstrate the dynamics of the sand charging. The numerically simulated charge-to-mass ratios of sands and electric field strength established in wind tunnel agreed well with the experimental data. The charging mechanism could provide an explanation for the charging process of all identical granular systems with water content, including Martian dust devils, wind-blown snow, even powder electrification in industrial processes.

Characterization of napthenic acids in oil sands process-affected waters using fluorescence technology

International Nuclear Information System (INIS)

Brown, L.; Alostaz, M.; Ulrich, A.

2009-01-01

Process-affected water from oil sands production plants presents a major environmental challenge to oil sands operators due to its toxicity to different organisms as well as its corrosiveness in refinery units. This abstract investigated the use of fluorescence excitation-emission matrices to detect and characterize changes in naphthenic acid in oil sands process-affected waters. Samples from oil sands production plants and storage ponds were tested. The study showed that oil sands naphthenic acids show characteristic fluorescence signatures when excited by ultraviolet light in the range of 260 to 350 mm. The signal was a unique attribute of the naphthenic acid molecule. Changes in the fluorescence signature can be used to determine chemical changes such as degradation or aging. It was concluded that the technology can be used as a non-invasive continuous water quality monitoring tool to increase process control in oil sands processing plants

Ground penetrating radar water content mapping of golf course green sand layers

Science.gov (United States)

Information on the spatial distribution of water content across the sand layer component of a golf course green can be important to golf course superintendents for evaluating drainage effectiveness and scheduling irrigation. To estimate the bulk water content of the sand layer at point locations ac...

Process water treatment in Canada's oil sands industry : 1 : target pollutants and treatment objectives

International Nuclear Information System (INIS)

Allen, E.W.

2008-01-01

The continuous recycling of tailings pond water in the oil sands industry has contributed to an overall decline in water quality used for bitumen recovery, general water consumption, and remedial activities. This paper reviewed process water quality and toxicity data from 2 long-term oil sands operations. The aim of the study was to determine potential roles for water treatment and provide benchmarks for the selection of candidate water treatment technologies in the oil sands region of Alberta. An overview of the oil sands industry was provided as well as details of bitumen recovery processes. The study examined target pollutants and exceedances identified in environmental and industrial water quality guidelines. The study demonstrated that the salinity of tailings pond water increased at a rate of 75 mg per litre per year between 1980 and 2001. Increases in hardness, chloride, ammonia, and sulphates were also noted. Naphthenic acids released during bitumen extraction activities were determined as the primary cause of tailings pond water toxicity. A summary of recent studies on experimental reclamation ponds and treatment wetlands in the oil sands region was included. 19 refs., 4 tabs., 11 figs

Presentations of the CONRAD Research Symposium : oil sands water usage workshop

International Nuclear Information System (INIS)

2004-01-01

This symposium provided a forum to exchange ideas regarding water use by the oil sands industry in Canada. The topics of discussion addressed timely issues such as corrosion control in pipelines, cumulative discharge modelling in the oil sands area, waste management schemes, the effects of potential limits on water withdrawal for thermal recovery operations and plant operations, the feasibility of geological sequestration of salts, and the impact of process-affected water on bitumen recovery. Other topics of discussion included tailings ponds management, deoxygenation of water, nanofiltration for water management, water quality for wetlands, water reuse, and water supply security. The conference featured 25 presentations, of which 17 have been indexed separately for inclusion in this database. tabs., figs

Processes of microbial pesticide degradation in rapid sand filters for treatment of drinking water

DEFF Research Database (Denmark)

Hedegaard, Mathilde Jørgensen; Albrechtsen, Hans-Jørgen

Aerobic rapid sand filters for treatment of groundwater at waterworks were investigated for the ability to remove pesticides. The potential, kinetics and mechanisms of microbial pesticide removal was investigated in microcosms consisting of filter sand, treated water and pesticides in initial...... concentrations of 0.04-2.4 μg/L. The pesticides were removed from the water in microcosms with filter sand from all three investigated sand filters. Within the experimental periode of six to 13 days, 65-85% of the bentazone, 86-93% of the glyphosate, 97-99% of the p-nitrophenol was removed from the water phase...

Fertilizer nitrogen leaching in relation to water regime and the fertilizer placement method

International Nuclear Information System (INIS)

Moustafa, A.T.A.; Khadr, M.S.

1983-01-01

A field experiment was conducted at the farm of Sids Experimental Station, Ministry of Agriculture, Middle Egypt, to evaluate the effect of the water regime and fertilizer placement method on the leaching of urea fertilizer under field conditions. Ordinary and heavy irrigations were the water regimes, while side-banding and surface broadcasting were the fertilizer placement methods. Wheat (Giza 158, local variety) was planted, and urea labelled with 15 N at the rate of 100 kg N/ha was added at planting. The data obtained showed that in general the leaching process of urea fertilizer, as evaluated from the amounts of fertilizer nitrogen residues, is not uniform even within replicates. This is despite the fact that the average total amount of fertilizer nitrogen residues in the soil profile to a depth of 125 cm is almost the same in the different treatments. Data also show that the bulk of fertilizer nitrogen residues is accumulated in the surface soil layers, especially at 0-25 cm. Only 10% of the fertilizer nitrogen is detected below 75 cm and up to 125 cm depth of the soil profile. It could be concluded that urea leaching (amount and depth) under these conditions is affected mainly by the soil characteristics, namely soil pores. This is in addition to some other factors that cause variable concentrations in the soil solution leaving the root zone. (author)

Evaluation of methods to sample fecal indicator bacteria in foreshore sand and pore water at freshwater beaches.

Science.gov (United States)

Vogel, Laura J; Edge, Thomas A; O'Carroll, Denis M; Solo-Gabriele, Helena M; Kushnir, Caitlin S E; Robinson, Clare E

2017-09-15

Fecal indicator bacteria (FIB) are known to accumulate in foreshore beach sand and pore water (referred to as foreshore reservoir) where they act as a non-point source for contaminating adjacent surface waters. While guidelines exist for sampling surface waters at recreational beaches, there is no widely-accepted method to collect sand/sediment or pore water samples for FIB enumeration. The effect of different sampling strategies in quantifying the abundance of FIB in the foreshore reservoir is unclear. Sampling was conducted at six freshwater beaches with different sand types to evaluate sampling methods for characterizing the abundance of E. coli in the foreshore reservoir as well as the partitioning of E. coli between different components in the foreshore reservoir (pore water, saturated sand, unsaturated sand). Methods were evaluated for collection of pore water (drive point, shovel, and careful excavation), unsaturated sand (top 1 cm, top 5 cm), and saturated sand (sediment core, shovel, and careful excavation). Ankle-depth surface water samples were also collected for comparison. Pore water sampled with a shovel resulted in the highest observed E. coli concentrations (only statistically significant at fine sand beaches) and lowest variability compared to other sampling methods. Collection of the top 1 cm of unsaturated sand resulted in higher and more variable concentrations than the top 5 cm of sand. There were no statistical differences in E. coli concentrations when using different methods to sample the saturated sand. Overall, the unsaturated sand had the highest amount of E. coli when compared to saturated sand and pore water (considered on a bulk volumetric basis). The findings presented will help determine the appropriate sampling strategy for characterizing FIB abundance in the foreshore reservoir as a means of predicting its potential impact on nearshore surface water quality and public health risk. Copyright © 2017 Elsevier Ltd. All rights

Integrated oil sands tailings pond water treatment

Energy Technology Data Exchange (ETDEWEB)

Guo, Z. [Saskatchewan Research Council, Saskatoon, SK (Canada)

2010-07-01

This PowerPoint presentation discussed research currently being conducted to treat oil sands tailings pond water (TPW). The treatment of TPW is challenged by the high level of naphthenic acids (NAs), the slow settling rate of fine particulate materials, and the complex chemistry of the water. The treatment process consisted of bioflocculation, sludge blanket assisted clarification, ozonation, and oil sands coke assisted hybrid biodegradation. The aggregation and adsorption process bound small particles and cells together while also ensuring the passive uptake of pollutants using microbial masses. The mixed liquor then passed through a sludge blanket to ensure enhanced particle capture. An ozonation process was used to increase the biodegradability of the TPW as well as to increase the biodegradability of the residual NAs after ozonation. The process used a hybrid bioreactor that consisted of both suspended and fixed microbial communities. The coke served as a biofilm carrier for the waste. Further studies are being conducted to investigate the efficiency and capability of the process. tabs., figs.

Biodegradation of gasoline compounds (BTEX) in a water works sand filter

DEFF Research Database (Denmark)

Arvin, Erik; Engelsen, P.; Sebber, U.

2004-01-01

Various chemical compounds including aromatic gasoline compounds frequently contaminate drinking water wells in urban areas. Because ground water treatment is simple, usually consisting of aeration/stripping and sand-filtration, it is of significant interest to know the ability of the conventional...... treatment to remove the chemical contaminants. The removal of gasoline compounds was investigated in a two-stage pilot scale sand filter, each with a filter depth of 0.8-1 m and with a filtration rate of 7.6 m/h. The concentrations of aromatic compounds were in the range 7-15 mu g/L, which are realistically...... sand grains). Influent iron concentrations in the range 0-4 mg/L and backwashing did not adversely affect the biodegradation of hydrocarbons. This study has shown that a conventional biological active sand filter can act as an efficient barrier against gasoline compounds, thereby saving the consumer...

Microbial pesticide removal in rapid sand filters for drinking water treatment – Potential and kinetics

DEFF Research Database (Denmark)

Hedegaard, Mathilde Jørgensen; Albrechtsen, Hans-Jørgen

2014-01-01

Filter sand samples, taken from aerobic rapid sand filters used for treating groundwater at three Danish waterworks, were investigated for their pesticide removal potential and to assess the kinetics of the removal process. Microcosms were set up with filter sand, treated water, and the pesticides...... or metabolites mecoprop (MCPP), bentazone, glyphosate and p-nitrophenol were applied in initial concentrations of 0.03–2.4 μg/L. In all the investigated waterworks the concentration of pesticides in the water decreased – MCPP decreased to 42–85%, bentazone to 15–35%, glyphosate to 7–14% and p-nitrophenol 1....../L) increased from 0.21%/g filter sand to 0.75%/g filter sand, when oxygen availability was increased from 0.28 mg O2/g filter sand to 1.09 mg O2/g filter sand. Bentazone was initially cleaved in the removal process. A metabolite, which contained the carbonyl group, was removed rapidly from the water phase...

Ground-Water Flow Direction, Water Quality, Recharge Sources, and Age, Great Sand Dunes National Monument, South-Central Colorado, 2000-2001

Science.gov (United States)

Rupert, Michael G.; Plummer, Niel

2004-01-01

Great Sand Dunes National Monument is located in south-central Colorado along the eastern edge of the San Luis Valley. The Great Sand Dunes National Monument contains the tallest sand dunes in North America; some rise up to750 feet. Important ecological features of the Great Sand Dunes National Monument are palustrine wetlands associated with interdunal ponds and depressions along the western edge of the dune field. The existence and natural maintenance of the dune field and the interdunal ponds are dependent on maintaining ground-water levels at historic elevations. To address these concerns, the U.S. Geological Survey conducted a study, in collaboration with the National Park Service, of ground-water flow direction, water quality, recharge sources, and age at the Great Sand Dunes National Monument. A shallow unconfined aquifer and a deeper confined aquifer are the two principal aquifers at the Great Sand Dunes National Monument. Ground water in the unconfined aquifer is recharged from Medano and Sand Creeks near the Sangre de Cristo Mountain front, flows underneath the main dune field, and discharges to Big and Little Spring Creeks. The percentage of calcium in ground water in the unconfined aquifer decreases and the percentage of sodium increases because of ionic exchange with clay minerals as the ground water flows underneath the dune field. It takes more than 60 years for the ground water to flow from Medano and Sand Creeks to Big and Little Spring Creeks. During this time, ground water in the upper part of the unconfined aquifer is recharged by numerous precipitation events. Evaporation of precipitation during recharge prior to reaching the water table causes enrichment in deuterium (2H) and oxygen-18 (18O) relative to waters that are not evaporated. This recharge from precipitation events causes the apparent ages determined using chlorofluorocarbons and tritium to become younger, because relatively young precipitation water is mixing with older waters

Stratification of nitrification activity in rapid sand filters for drinking water treatment

DEFF Research Database (Denmark)

Tatari, Karolina; Smets, Barth F.; Musovic, Sanin

2013-01-01

Rapid sand filters used in groundwater treatment remove ammonium, iron and manganese from the water. Ammonium is removed biologically by nitrifying microorganisms attached on the sand surface. Nitrification kinetics and activity is strongly affected by filter design and operation, which are the key...... and maximum nitrification capacity are derived and used to quantify nitrification activity. Nitrification activity was concentrated at the top 10 cm of filter depth, and maximum nitrification capacity was 7 g NH4+-N/ m3 sand/h compared with 0.8-0.4 g NH4+-N/ m3 sand/h in the middle and bottom layers. A water...... of this study is to investigate nitrification activity in a rapid sand filter, with focus on its homogeneity and how it relates to filter performance. Two groundwater treatment plants in Denmark were selected for the experimental investigations. Plant 1 operates a single line of pre and after filters and has...

Microbial degradation of pesticides in rapid sand filters used for drinking water treatment

DEFF Research Database (Denmark)

Hedegaard, Mathilde Jørgensen

significantly with the maximum methane concentration in the raw water and did not correlate with other water quality parameters, such as the ammonium concentration. Furthermore, the connection between bentazone degradation and methane oxidation in filter sand was demonstrated by inhibition experiments, in which...... sustainable methods to remove pesticides from polluted water sources. Aeration of anaerobic groundwater, followed by biological rapid sand filtration is a widespread technology in drinking water treatment. Even though these systems are not designed for removal of trace contaminants, they have shown potential...... for microbial degradation of pesticides and their degradation products. If pesticides can be removed in rapid sand filters, it is of large commercial interest due to the importance in maintaining a simple, sustainable water treatment. To take advantage of the microbial pesticide degradation and identify...

Use of isotopically labeled fertilizer to trace nitrogen fertilizer contributions to surface, soil, and ground water

Science.gov (United States)

Wilkison, D.H.; Blevins, D.W.; Silva, S.R.

2000-01-01

The fate and transport of a single N fertilizer application through plants, soil, runoff, and the unsaturated and saturated zones was determined for four years at a field site under continuous corn (Zea mays L.) management. Claypan soils, which underlie the site, were hypothesized to restrict the movement of agrichemicals from the soil surface to ground water. However, N fertilizer moved rapidly through preferential flow paths in the soil and into the underlying glacial till aquifer. Most N transport occurred during the fall and winter when crops were not available to use excess N. Forty months after application, 33 percent of the fertilizer had been removed by grain harvests, 30 percent had been transpired to the atmosphere, and 33 percent had migrated to ground water. Although runoff volumes were 50 percent greater than infiltration, less than 2 percent of the fertilizer was lost to runoff. Small measured denitrification rates and large measured dissolved oxygen concentrations in ground water favor the long-term stability of NO3-1 in ground water. Successive fertilizer applications, in areas that lack the ability to moderate N concentrations through consumptive N reactions, risk the potential of N-saturated ecosystems.

Sand and gravel mining: effects on ground water resources in Hancock county, Maine, USA

Science.gov (United States)

Peckenham, John M.; Thornton, Teresa; Whalen, Bill

2009-01-01

Based on this preliminary study, existing sand and gravel mining regulations (in Maine, USA) can be inferred to provide some protection to water resources. Sand and gravel deposits are important natural resources that have dual uses: mining for construction material and pumping for drinking water. How the mining of sand and gravel affects aquifers and change aquifer vulnerability to contamination is not well documented. Mining regulations vary greatly by state and local jurisdiction. This study test metrics to measure the effectiveness of mining regulations. The sand and gravel aquifer system studied is covered with former and active gravel pits to nearly 25% of its areal extent. Data from homeowner interviews and field measurements found scant evidence of changes in water quantity. Water quality analyses collected from springs, streams, ponds and wells indicate that the aquifer was vulnerable to contamination by chloride and nitrate. However, water quality changes can not be related directly to mining activities.

Process water treatment in Canada's oil sands industry : 2 : a review of emerging technologies

International Nuclear Information System (INIS)

Allen, E.W.

2008-01-01

This review was conducted to identify candidate treatment technologies for treating oil sands process water. The oil sands industry in Canada uses large volumes of fresh water in order to extract bitumen deposits. The development of process water treatment technologies has become a critical issue for the industry, particularly as oil sand production is expected to triple in the next decade. However, treatment technologies must be adapted to consider the fouling potential of bitumens and fine clays as well as the effect of alkaline process water on treatment performance. The review included developments in chemical modifications to membranes and adsorbents designed to improve pollutant removal and reduce fouling; hybridization technologies designed to enhance the biological treatment of toxic feedwaters; recent advances in photocatalytic oxidation technologies for organic compounds; and new designs for large-scale treatment wetlands for polluted waste waters. It was concluded that major knowledge gaps must be optimized and preliminary studies must be conducted in order to understand how the treatment technologies will be affected by the chemical and physical characteristics of oil sands process water. 188 refs., 8 tabs

Survival potential of Escherichia coli and Enterococci in subtropical beach sand: implications for water quality managers.

Science.gov (United States)

Hartz, A; Cuvelier, M; Nowosielski, K; Bonilla, T D; Green, M; Esiobu, N; McCorquodale, D S; Rogerson, A

2008-01-01

Fecal bacteria have traditionally been used as indicator organisms to monitor the quality of recreational waters. Recent work has questioned the robustness of traditional indicators, particularly at seawater bathing beaches. For example, a study of Florida beaches found unexpectedly high abundances of Escherichia coli, fecal coliforms, and enterococci in beach sand. The aim of the present study was to explain these abundances by assessing the survival of E. coli and enterococci in beach sand relative to seawater. We used a combination of quantitative laboratory mesocosm experiments and field observations. Results suggested that E. coli and enterococci exhibited increased survivability and growth in sand relative to seawater. Because fecal bacteria are capable of replicating in sand, at least under controlled laboratory conditions, the results suggest that sand may be an important reservoir of metabolically active fecal organisms. Experiments with "natural" mesocosms (i.e., unsterilized sand or water rich in micropredators and native bacteria) failed to show the same increases in fecal indicators as was found in sterile sand. It is postulated that this was due to predation and competition with indigenous bacteria in these "natural" systems. Nonetheless, high populations of indicators were maintained and recovered from sand over the duration of the experiment as opposed to the die-off noted in water. Indicator bacteria may wash out of sand into shoreline waters during weather and tidal events, thereby decreasing the effectiveness of these indicators as predictors of health risk and complicating the interpretations for water quality managers.

Transport of nanoparticles with dispersant through biofilm coated drinking water sand filters.

Science.gov (United States)

Li, Zhen; Aly Hassan, Ashraf; Sahle-Demessie, Endalkachew; Sorial, George A

2013-11-01

This article characterizes, experimentally and theoretically, the transport and retention of engineered nanoparticles (NP) through sand filters at drinking water treatment plants (DWTPs) under realistic conditions. The transport of four commonly used NPs (ZnO, CeO2, TiO2, and Ag, with bare surfaces and coating agents) through filter beds filled with sands from either acid washed and calcined, freshly acquired filter media, and used filter media from active filter media, were investigated. The study was conducted using water obtained upstream of the sand filter at DWTP. The results have shown that capping agents have a determinant importance in the colloidal stability and transport of NPs through the different filter media. The presence of the biofilm in used filter media increased adsorption of NPs but its effects in retaining capped NPs was less significant. The data was used to build a mathematical model based on the advection-dispersion equation. The model was used to simulate the performance of a scale-up sand filter and the effects on filtration cycle of traditional sand filtration system used in DWTPs. Published by Elsevier Ltd.

High-temperature expansion and knock-out properties of moulding sands with water glass

Directory of Open Access Journals (Sweden)

Major-Gabryś K.

2007-01-01

Full Text Available The article focuses on the topic of improving the knock-out properties of moulding sand with water glass and ester hardener. It is settled that the cause of worse knock-out properties of moulding sand can be brought by their thermal expansion in increased temperatures. There is a presentation of the influence of different additives, containing Al2O3, on moulding sands’ expansion in increased temperatures. Within the frames of research, there was an elaboration of the influence of authors own additive- Glassex, on the expansion phenomenon of moulding sands with water glass and ester hardener. It is concluded, that the new additive stops the expansion of moulding sands and as well it improves their knock-out properties.

Water Use for Cultivation Management of Watermelon in Upland Field on Sand Dune

Science.gov (United States)

Hashimoto, Iwao; Senge, Masateru; Itou, Kengo; Maruyama, Toshisuke

Early-maturing cultivation of watermelon in a plastic tunnel was invetigated in upland field on sand dune on the coast of the Japan Sea to find water use to control blowing sand and to transplant seedlings. This region has low precipitation, low humidity, and strong wind in March and April, when sand is readily blown in the field. Water is used to control blowing sand on days with precipitation below 5 mm, minimum humidity below the meteorological average in April, and maximum wind velocity above the meteorological average in April. For the rooting and growth of watermelon seedlings, soil temperature needs to be raised because it is low in April. Ridges are mulched with transparent, porous polyethylene films 10 or more days before transplanting the seedlings and irrigated with sprinklers on fine days for the thermal storage of solar energy. The stored heat steams the mulched ridges to raise soil temperature to 15°C or higher on the day of transplanting the seedlings. The total amount of irrigation water used for watermelon cultivation was 432.7 mm, of which 23.6 mm was for blowing sand control and 26.6 mm was for transplanting the seedlings. The combined amount, 50.2 mm, is 11.6% of the total amount of water used for cultivation management.

Impact of fertilizer plant effluent on water quality

International Nuclear Information System (INIS)

Obire, O.; Ogan, A.; Okigbo, R. N.

2008-01-01

The impact of National Fertilizer Company of Nigeria out fall effluent on the physico chemistry and bacteriology of Okrika creek was investigated during the sampling period from May to December, 1998. The National Fertilizer Company of Nigeria out fall effluent, the Okrika creek water and the lkpukulubie creek (control) water samples were collected. The physico-chemical parameters analyzed for all the samples included temperature, p H, total chloride, total dissolved solids, dissolved oxygen, conductivity, free ammonia, total phosphate, urea, zinc and iron, while the bacteriological determinations were total culturable aerobic heterotrophic bacteria count and identification of representative isolates. The Okrika creek recorded higher concentrations for all the physicochemical parameters and bacteria load than the control creek. The higher values of p H, Free NH 3 , urea, TDS and the conductivity of the National Fertilizer Company of Nigeria out fall effluent above the FEPA standards reflect the poor effluent quality generated by National Fertilizer Company of Nigeria. The bacteria species isolated from the samples include Aerococcus viridans, Alcaligenes faecalis, Bacillus cereus, Citrobacter freundii, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens and Staphylococcus aureus. In general, the investigation revealed that there was an extremely adverse impact on the physico-chemical and bacteriological water quality characteristics of the Okrika creek as a result of the discharge of poor quality effluent from National Fertilizer Company of Nigeria operations

Yellow perch embryo-larval survival and growth in surface waters associated with oil-sands mining

International Nuclear Information System (INIS)

Peters, L.E.; Heuvel, M.R. van den; Dixon, D.G.; Power, M.; Boerger, H.; MacKinnon, M.D.; Meer, T. Van

1995-01-01

As part of their land reclamation strategy, Syncrude Canada Ltd. is currently developing environmentally acceptable tailings disposal methods. Fine tailings, a suspension of clay and residual bitumen, is the waste product from oil sands extraction. Fine-tailings contain naphthenic acids, a group of saturated aliphatic and alicyclic carboxylic acids, which occur naturally in petroleum and are partly responsible for the toxicity of process water. The wet landscape method involves covering fine tails with a layer of water such that a self-sustaining ecosystem can be established. A 5 ha demonstration pond with a bottom of fine-tailings was constructed and stocked with yellow perch for experimental purposes. Two other reclaimed ponds formed with oil-sands overburden material were also stocked with perch. Adult perch sampled in the fall of 1995 from the experimental and reclaimed ponds exhibited a 2-fold induction of MFO activity compared to the source lake; indicating organic compound exposure. Perch from one of the reclaimed ponds showed significantly reduced circulating reproductive hormone levels, gonad size and smaller ovarian follicles. Reproductive parameters were not different between the source lake and the remaining ponds. Paired lab and field experiments were conducted to determine if contaminants present would be detrimental to egg viability and development of larvae either through direct exposure of spawned eggs or indirectly by effecting oogenesis. An early life stage toxicity test was also performed using commercially available naphthenic acid standard. Endpoints measured were percent fertilization, percent hatch, mortality, deformities, timing of developmental periods and larval growth

Peatland fertilization. Short-term chemical effects on runoff water

Energy Technology Data Exchange (ETDEWEB)

1986-01-01

In peatland forestry, fertilization is often needed to reach a good yield. Phosphorus and potassium are mainly used, but on nutrient poor fens and bogs, nitrogen also has be added. These fertilizers affect the environment and thereby influence the runoff waters. This essay concerns the first three months after fertilization, of which the first two weeks have been paid particular attention. As the mires of the sub-basins were sedge fens, with a pine stand in some areas but mostly treeless, the fertilizers used were ammonium nitrate , rock phosphate and potassium chloride . The fertilization was performed from the air. During the very first hours after fertilization, drastic changes in water chemistry were found. In one area pH dropped 0,3 units while at the other no immidiate change was seen. For the whole three months of the investigation period, the decreases in pH were in the range 0,1-0,5 units. Nitrogen concentration reached a peak of 260 mg/l, phosphorus 5 mg/l and potassium about 60 mg/l. These high values were of short duration but the concentrations were considerable increased during one week. Later, partly due to decreasing discharge, the water chemistry became almost similar to that measured under unfertilized conditions. The main loss of fertilizer occurred during the first two weeks and amounted to 22% of the applied nitrogen, about 1% of the phosphorus and 5-9% of K.

WATER CHEMISTRY IN DIFFERENTLY FERTILIZED CARP POUNDS

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Krešimir Fašaić

1997-07-01

Full Text Available Water chemistry in carp ponds - fry carp ponds, each of them 2.5 acres big and 1.5 meter deep, as well as in inflow water in the ponds was researched. Fourty days old carp fingerlings were bread in the ponds; stock density of the three day old larvae was 1,000.000 ind˙ha-1. The fingerlings were fed with trouvit and flour. In the ponds and the inflow water the following chemical parameters were examined: : 02, C02, CaC03-, RC03-, outgoing of KMn04, N02-, N03-, NR4+, urea, PO43-, P205 and pH. During the breeding season substantial deviations of all the chemical parameters were stated, but within values that satisfy the needs of the carp ponds. The applied quantity of the mineral fertilizer did not cause a very explicit eutrophication of water in the treated ponds. Certain differences in the quantity of the respective chemical indicators in the fertilized pond variants compared to the nonfertilized variant were insignificant (P**0.05, except the pH value, which increased significantly in the fertilized variants (P<0.05. Compared with the inflow water, in all experimental ponds the quantity of the mineral nitrogen and phosphorus fractions (P<0.05, (P<0.05 has increased. (Tables 5 and 6

The influence of microwave heating and water glass kind on the properties of molding sands

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K. Granat

2008-03-01

Full Text Available This work presents rcsults of research on thc influcncc of microwave heating time on the process of hardening of warcr glass moldingsands. Essential influence of this drying process on basic properties such as: cornprcssion, bcnding mind tcnsitc strcng~h as well aspcrrneabili~y and war resistance, has bccn found. It has bccn proved, that at1 thc investigated sorts of sodium water glass could be uscd asbinding material of molding sands intended for curing with the microwave process healing. It has bccn found, while analyzing the rcsultsof property studics or microwavc heated molding sands with 2.5% addition of water glass, that aIl available on the markct kinds of thisbinding agent (inctuding the most frequently uscd in foundry 145 and 149 kinds after microwave heating guarantee very goodcompression, bending and tensile strength as well as permeability and wcar resistance. Moroovcr, it has bccn dctcrmined that the optimalcuring powcr of molding sands containing various kinds of water gIass is 560 W. AII values exceeding this rcsult in stabilization of basicpropcrtics of molding sands. The use of microwave curing of water glass molding sands results in a significant decrease of hardeningprocess time. full stabilization of molding sands as well as much lower energy consumption.

Application of forward osmosis membrane technology for oil sands process-affected water desalination.

Science.gov (United States)

Jiang, Yaxin; Liang, Jiaming; Liu, Yang

2016-01-01

The extraction process used to obtain bitumen from the oil sands produces large volumes of oil sands process-affected water (OSPW). As a newly emerging desalination technology, forward osmosis (FO) has shown great promise in saving electrical power requirements, increasing water recovery, and minimizing brine discharge. With the support of this funding, a FO system was constructed using a cellulose triacetate FO membrane to test the feasibility of OSPW desalination and contaminant removal. The FO systems were optimized using different types and concentrations of draw solution. The FO system using 4 M NH4HCO3 as a draw solution achieved 85% water recovery from OSPW, and 80 to 100% contaminant rejection for most metals and ions. A water backwash cleaning method was applied to clean the fouled membrane, and the cleaned membrane achieved 77% water recovery, a performance comparable to that of new FO membranes. This suggests that the membrane fouling was reversible. The FO system developed in this project provides a novel and energy efficient strategy to remediate the tailings waters generated by oil sands bitumen extraction and processing.

Chemical properties of a Haplustalf soil under irrigation with treated wastewater and nitrogen fertilization

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Leda V. B. D. Silva

2016-04-01

Full Text Available ABSTRACT The objective of this research was to investigate the effects of irrigation with treated wastewater and nitrogen (N fertilization on the chemical characteristics of a Haplustalf soil cultivated with cotton. An experiment was conducted in a greenhouse in a completely randomized design with four replicates, and arranged in a 5 x 4 factorial. Five doses of N fertilization (0, 45, 90, 135 and 180 kg ha-1 and four sources of irrigation water (freshwater, wastewater treated by an anaerobic reactor, wastewater treated by an anaerobic reactor and post-treated by intermittent sand filter in series, wastewater treated in a septic tank and post-treated by an intermittent sand filter were tested. Irrigation was daily performed from July 2011 to January 2012 according to the water demand of cotton resulting in a water depth of 620 mm. It was found that, compared with the conventional management with freshwater irrigation, treated wastewater provides greater accumulation of micronutrient, potassium and sodium in the soil, increasing the risk of sodification in irrigated areas.

Investigation of Water Holding Capacity of Sugarcane Mulch for Sand Dune Stabilization in Ahvaz

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T. Jamili

2017-01-01

Full Text Available Introduction: Wind erosion is one of the most serious problems in southwest Iran. Fine-grained structure of sand dunes with not enough strong composition and their low moisture retention property make them susceptible to wind erosion. They lack organic matter and are considered inherently of low fertility (Ahmadi, 2002. Studies have shown that non-erodible materials which include bentonite clay (Diouf et al., 1990, ureamelamine formaldehyde and urea–formaldehyde with 0.25% sodium chloride (Lahalih and Ahmed, 1998, acids, enzymes, lignosulfonates, polymers, tree resins (Santoni et al., 2001, waterborne polymer emulsion (Al-Khanbashi and Abdalla, 2006, polyvinyl alcohol and a polyvinyl acetate emulsion (Newman et al., 2005; Han et al., 2007, ash and polyacrylamide (Yang and Zejun, 2012.have significant potential in reducing wind erosion The area under farming of sugarcane in Khuzestan, Iran, is more than 130,000, ha. Vinasse and Filter Kike are two organic ingredients of sugarcane residues which are generated as byproduct materials insugarcane processing. In recent years these residues have been released into the environment and cause it regarded as water pollutant. Over 800,000 m3 of Vinasse is annually stored in each agro-industry. Vinasse also is rich in K, Ca, and Mg with moderate amounts of P and N,and non toxic complexes or heavy metals. Filter Kike is another residue produced in huge amounts by the agro-industry that is composed of cellulosic substances, CaCO3, N, P, K, organic matter, and clay. Therefore, the objective of this research is to investigate the effect of sugarcane mulch on water holding capacity in soil. This study is performed to evaluate the feasibility of using sugarcane residues inproduce of ecofriendly mulches for environmental use. In order of achieving these goals, Vinase, Filter Cake, and clay soil from near the sand dunes were used as sugarcane mulches. Further comparison between traditional oil mulches and

Development of a bioassay to assess the toxicity of oil sands sediments to pike (Esox lucius)

Energy Technology Data Exchange (ETDEWEB)

Turcotte, D.; Yuan, H.; Tumber, V.; Parrott, J. [Environment Canada, Ottawa, ON (Canada); Raine, J. [Saskatchewan Univ., Saskatoon, SK (Canada)

2010-07-01

Pike (Esox lucius) are a commercially sought fish species that inhabit the Athabasca River, which flows through the Athabasca oil sands. The fish are exposed to natural sources of bitumen from the McMurray formation. This study was conducted to design and implement a daily-renewal bioassay to assess the toxicity of oil sands to this fish species and to obtain information regarding the development of pike exposed to bitumen. Eggs were collected and fertilized with milt from spawning wild pike captured from Lake Diefenbaker in Saskatchewan. The fertilized eggs were exposed to different concentrations of sediments or culture water only (negative controls) until complete yolk absorption of control fish, approximately 15 days post-hatch. For the rest of the experiment, brine shrimp were fed to the walleye embryos every day after hatching. The developing fish were examined for morphological deformities, survival, hatching success, and changes in weight and length. The research findings indicated that pike is less sensitive than walleye and fathead minnow to the toxicity of oil sands sediments.

Successful water management for the oil sands industry

International Nuclear Information System (INIS)

Braun, B.

2003-01-01

Water is a key requirement to produce oil from thermal oil sands projects. Historically, water was considered as a renewable resource that could be used when necessary. Water use is currently examined in a wider context. Canadian Natural Resources Limited has used fresh water for thermal projects in the past, including its thermal operations at Primrose and Wolf Lake. However, technical advancements have made it possible to use recycled water. This allows companies to survive within their licenses while increasing production. Other advances include the use of brackish water, and innovations such as using depleted reservoir sections to store water to increase the use of recycled water. It was noted that brackish water resources need to be mapped and understood in greater detail. The objective is to use brackish water at a cost equal to, or less, than fresh water

Selection of inorganic-based fertilizers in forward osmosis for water desalination

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Tripti Mishra

2015-06-01

Full Text Available The current study aims at the selection of an appropriate draw solute for forward osmosis process. Separation and recovery of the draw solute are the major criteria for the selection of draw solute for forward osmosis process. Therefore in this investigation six inorganic fertilizers draws solute were selected. The selections of inorganic fertilizers as draw solute eliminate the need of removal and recovery of draw solute from the final product. The final product water of forward osmosis process has direct application in agricultural as nutrient rich water for irrigation. These inorganic fertilizers were tested based on their water extraction (water flux capacity. This experimental water flux was compared with the observed water flux. It was noted that the observed water flux is much higher than the attained experimental water flux. The difference of these two fluxes was used to calculate the performance ratio of each selected fertilizer. Highest performance ratio was shown by low molecular weight compound ammonium nitrate (22.73 and potassium chloride (21.03 at 1 M concentration, whereas diammonium phosphate (DAP which has highest molecular weight among all the selected fertilizer show the lowest performance ratio (10.02 at 2 M concentration. DOI: http://dx.doi.org/10.3126/ije.v4i2.12660 International Journal of Environment Vol.4(2 2015: 319-329

Barley root hair growth and morphology in soil, sand, and water solution media and relationship with nickel toxicity.

Science.gov (United States)

Lin, Yanqing; Allen, Herbert E; Di Toro, Dominic M

2016-08-01

Barley, Hordeum vulgare (Doyce), was grown in the 3 media of soil, hydroponic sand solution (sand), and hydroponic water solution (water) culture at the same environmental conditions for 4 d. Barley roots were scanned, and root morphology was analyzed. Plants grown in the 3 media had different root morphology and nickel (Ni) toxicity response. Root elongations and total root lengths followed the sequence soil > sand > water. Plants grown in water culture were more sensitive to Ni toxicity and had greater root hair length than those from soil and sand cultures, which increased root surface area. The unit root surface area as root surface area per centimeter of length of root followed the sequence water > sand > soil and was found to be related with root elongation. Including the unit root surface area, the difference in root elongation and 50% effective concentration were diminished, and percentage of root elongations can be improved with a root mean square error approximately 10% for plants grown in different media. Because the unit root surface area of plants in sand culture is closer to that in soil culture, the sand culture method, not water culture, is recommended for toxicity parameter estimation. Environ Toxicol Chem 2016;35:2125-2133. © 2016 SETAC. © 2016 SETAC.

Intertidal beach sands as monitors for heavy metal pollution in coastal water bodies

International Nuclear Information System (INIS)

Lacerda, L.D. de; Pfeiffer, W.C.; Fiszman, M.

Intertidal beach sands were investigated for their use as indicators of metal transport in a contaminated water body, Sepetiba Bay, Rio de Janeiro, Brazil, and are proposed as an alternative and rapid screening method to determine metal pollution status of coastal areas. The results showed that, at least for Cu, Cr, Zn and Pb, beach sands can be included in the existing environmental monitoring programs for heavy metal pollution in water bodies. (Author) [pt

Microbiological quality assessment of sand and water from three selected beaches of South Coast, São Paulo State, Brazil.

Science.gov (United States)

Pinto, K C; Hachich, E M; Sato, M I Z; Di Bari, M; Coelho, M C L S; Matté, M H; Lamparelli, C C; Razzolini, M T P

2012-01-01

This study aimed to assess the sanitary quality of water, and wet and dry sand from three beaches located in the South Coast region of São Paulo State, Brazil, selected taking into account the frequency of tourists and the water quality (good, fair and poor). Thirty-six water samples each of wet and dry sand and seawater were collected monthly over a period of one year and analyzed for fecal indicator bacteria (FIB: thermotolerant coliforms, Escherichia coli, and enterococci), presumptive Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and dermatophytes. The results revealed FIB concentrations more elevated in dry sand followed by wet sand and water. P. aeruginosa and presumptive S. aureus were detected with a similar frequency in water and sand samples, but maximum concentrations and geometric means were higher in dry sand. C. albicans was detected only in water samples whereas the dermatophyte Microsporum sp. was isolated exclusively from dry and wet sand samples. This evaluation showed also that the environment had a significant influence on P. aeruginosa but not on presumptive S. aureus concentrations. According to threshold values proposed in the literature for E. coli and enterococci dry sand densities, none of the beaches would be considered of sufficient quality for recreational activities.

Seasonal energy, water, and food consumption of Negev Chukars and sand partridges

International Nuclear Information System (INIS)

Kam, M.; Degen, A.A.; Nagy, K.A.

1987-01-01

Chukars (Alectoris chukar) and Sand Partridges (Ammoperdix heyl), two ground-dwelling phasianids, are permanent residents of the Negev desert and are sympatric over much of their ranges. Sand Partridges (body mass = 150-250 g), however, inhabit only arid and very arid areas, whereas Chukars (m/sub b/ = 350-600 g) are widely distributed and inhabit deserts only at the margins of their ranges. They compared some of the desert adaptations of these phasianids by measuring the seasonal field metabolic rates (FMR) and water influxes (using doubly labelled water), diet selection, and food requirements of free-living Chukars and Sand Partridges at a site where both species occurred. Both species showed adaptation in the form of low energy metabolism, which ranged from 43 to 81% of that expected for birds of similar body mass. During summer, Sand Partridges had lower energy expenditures (5.47 kJ x g/sup -0.61/ x d -1 ) and water influxes (72.3 mL kg/sup -0.75/ d -1 ) than did Chukars (6.42 kJ g/sup -0.61/ d -1 and 93.5 mL x kg/sup -0.75/ x d -1 , respectively), indicating more pronounced adjustments to arid conditions in the desert specialist. However, both species obtained more than half of their water influx in summer by drinking. Their summer diet was relatively dry, consisting mainly of seeds (80%) along with some green vegetation (18%) and, in Chukars, occasional arthropods. This situation changed abruptly after winter rains, which induced germination and reduced the availability of seeds. Chukars were unable to maintain energy balance in the face of low ambient temperatures and a diet (90% green vegetation) that contained much water but comparatively little energy, and they mobilized fat reserves to meet energy requirements. Most Sand Partridges left the study area after winter rains, apparently migrating to the lower elevation, warmer, and drier Arava (part of the Rift Valley)

Deflouridation of water using physico-chemically treated sand as a ...

African Journals Online (AJOL)

Prof. Dr. Mahamadi

chemically modified sand has potential application as an adsorbent for fluoride ions removal. ... activated carbon, minerals, fish bone charcoal, coconut ... (2003), established that red soils ..... solutions by granular ferric hydroxide (GFH). Water ...

Biodegradation of aliphatic vs. aromatic hydrocarbons in fertilized arctic soils

Science.gov (United States)

Braddock, J.F.

1999-01-01

A study was carried out to test a simple bioremediation treatment strategy in the Arctic and analyze the influence of fertilization the degradation of aliphatic and aromatic hydrocarbons, e.g., pristine, n-tetradecane, n-pentadecane, 2-methylnaphthalene, naphthalene, and acenaphthalene. The site was a coarse sand pad that once supported fuel storage tanks. Diesel-range organics concentrations were 250-860 mg/kg soil at the beginning of the study. Replicate field plots treated with fertilizer yielded final concentrations of 0, 50, 100, or 200 mg N/kg soil. Soil pH and soil-water potentials decreased due to fertilizer application. The addition of fertilizer considerably increased soil respiration potentials, but not the populations of microorganisms measured. Fertilizer addition also led to ??? 50% loss of measured aliphatic and aromatic hydrocarbons in surface and subsurface soils. For fertilized plots, hydrocarbon loss was not associated with the quantity of fertilizer added. Losses of aliphatic hydrocarbons were ascribed to biotic processes, while losses of aromatic hydrocarbons were due to biotic and abiotic processes.

Liquid organomineral fertilizer containing humic substances on soybean grown under water stress

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Marcelo R. V. Prado

2016-05-01

Full Text Available ABSTRACT This study evaluated the effect of an organomineral fertilizer enriched with humic substances on soybean grown under water stress. The experiment was performed in a greenhouse using a Red Latosol (Oxisol with adequate fertility as substrate, in which soybean plants were cultivated with and without water stress. The experimental design was randomized blocks, in a 2 x 5 factorial scheme (two moisture levels and five fertilizer doses: 0, 1, 2, 4 and 8 mL dm-3, totaling 10 treatments, with four replicates. The organomineral fertilizer was applied in the soil 21 days after plant emergence and the water regimes were established one week thereafter. The fertilizer was not able to attenuate the effects of water stress, reducing soybean grain yield by more than 50% compared with plants cultivated under no stress. Fertilizer doses caused positive response on soybean nutrition and grain yield and, under water stress condition, the most efficient dose was 5.4 mL dm-3. There were lower leaf concentrations of nitrogen, phosphorus and potassium and higher concentrations of sulfur in plants under stress. Humic substances favor the absorption of micronutrients.

Replicating the microbial community and water quality performance of full-scale slow sand filters in laboratory-scale filters.

Science.gov (United States)

Haig, Sarah-Jane; Quince, Christopher; Davies, Robert L; Dorea, Caetano C; Collins, Gavin

2014-09-15

Previous laboratory-scale studies to characterise the functional microbial ecology of slow sand filters have suffered from methodological limitations that could compromise their relevance to full-scale systems. Therefore, to ascertain if laboratory-scale slow sand filters (L-SSFs) can replicate the microbial community and water quality production of industrially operated full-scale slow sand filters (I-SSFs), eight cylindrical L-SSFs were constructed and were used to treat water from the same source as the I-SSFs. Half of the L-SSFs sand beds were composed of sterilized sand (sterile) from the industrial filters and the other half with sand taken directly from the same industrial filter (non-sterile). All filters were operated for 10 weeks, with the microbial community and water quality parameters sampled and analysed weekly. To characterize the microbial community phyla-specific qPCR assays and 454 pyrosequencing of the 16S rRNA gene were used in conjunction with an array of statistical techniques. The results demonstrate that it is possible to mimic both the water quality production and the structure of the microbial community of full-scale filters in the laboratory - at all levels of taxonomic classification except OTU - thus allowing comparison of LSSF experiments with full-scale units. Further, it was found that the sand type composing the filter bed (non-sterile or sterile), the water quality produced, the age of the filters and the depth of sand samples were all significant factors in explaining observed differences in the structure of the microbial consortia. This study is the first to the authors' knowledge that demonstrates that scaled-down slow sand filters can accurately reproduce the water quality and microbial consortia of full-scale slow sand filters. Copyright © 2014 Elsevier Ltd. All rights reserved.

Parameters and mechanisms in the mechanical upgrading of Athabasca oil sands by a cold water process

Energy Technology Data Exchange (ETDEWEB)

Grant, G B

1977-01-01

The efficiency of sand rejection in the cold water mechanical upgrading of Athabasca oil sands has been studied in the operation of rotary contactors of 8.9 cm and 19.0 cm internal diameter, fitted with lifters. Duration of operation, rate of rotation, linear velocity of lifters, temperature, water to oil sands ratio, depth of charge to lifter height ratio, and internal diameter of the contactor have been identified as important parameters. Surfactant addition and presoaking of the feed had negligible effects on the process. A model has been proposed that accounts for the variation of extraction efficiency as a function of duration of operation, the data showing that both the equilibrium extraction efficiency and the rate constant were greater in the large contactor than the small contactor for equal rates of rotation, except when centrifuging occurred in the large contactor. Sand rejection was promoted by lifter-sand and contactor wall-sand impacts and by the action of shear fields within vortices created by the lifter. The impacts occurred for all loading conditions but the latter mechanism only contributed to the sand rejection process for depth-of-charge to lifter height ratios of one or greater. In addition, the contribution of shear fields was only significant for large water to oil sands ratios. Finally, the sand rejection process was affected significantly by variations in temperature. 37 refs., 34 figs., 11 tabs., 4 illus.

Influence of Geometric Parameters of the Hydrocyclone and Sand Concentration on the Water/Sand/Heavy-Oil Separation Process: Modeling and Simulation

Directory of Open Access Journals (Sweden)

F Farias

2016-09-01

Full Text Available In the oil exploitation, produced fluids are composed of oil, gas, water and sand (depending on the reservoir location. The presence of sand in flow oil leads to several industrial problems for example: erosion and accumulation in valves and pipeline. Thus, it is necessary to stop production for manual cleaning of equipments and pipes. These facts have attracted attention of academic and industrial areas, enabling the appearing of new technologies or improvement of the water/oil/sand separation process. One equipment that has been used to promote phase separation is the hydrocyclone due to high performance of separation and required low cost to installation and maintenance. In this sense, the purpose of this work is to study numerically the effect of geometric parameters (vortex finder diameter of the hydrocyclone and sand concentration on the inlet fluid separation process. A numerical solution of the governing equations was obtained by the ANSYS CFX-11 commercial code. Results of the streamlines, pressure drop and separation efficiency on the hydrocyclone are presented and analyzed. It was observed that the particles concentration and geometry affect the separation efficiency of the hydrocyclone.

Evaluation of fertilization-to-planting and fertilization-to-harvest intervals for safe use of noncomposted bovine manure in Wisconsin vegetable production.

Science.gov (United States)

Ingham, Steven C; Fanslau, Melody A; Engel, Rebecca A; Breuer, Jeffry R; Breuer, Jane E; Wright, Thomas H; Reith-Rozelle, Judith K; Zhu, Jun

2005-06-01

Fresh bovine manure was mechanically incorporated into loamy sand and silty clay loam Wisconsin soils in April 2004. At varying fertilization-to-planting intervals, radish, lettuce, and carrot seeds were planted; crops were harvested 90, 100, 110 or 111, and 120 days after manure application. As an indicator of potential contamination with fecal pathogens, levels of Escherichia coli in the manure-fertilized soil and presence of E. coli on harvested vegetables were monitored. From initial levels of 4.0 to 4.2 log CFU/g, E. coli levels in both manure-fertilized soils decreased by 2.4 to 2.5 log CFU/g during the first 7 weeks. However, E. coli was consistently detected from enriched soil samples through week 17, perhaps as a result of contamination by birds and other wildlife. In the higher clay silty clay loam soil, the fertilization-to-planting interval affected the prevalence of E. coli on lettuce but not on radishes and carrots. Root crop contamination was consistent across different fertilization-to-harvest intervals in silty clay loam, including the National Organic Program minimum fertilization-to-harvest interval of 120 days. However, lettuce contamination in silty clay loam was significantly (P < 0.10) affected by fertilization-to-harvest interval. Increasing the fertilization-to-planting interval in the lower clay loamy sand soil decreased the prevalence of E. coli on root crops. The fertilization-to-harvest interval had no clear effect on vegetable contamination in loamy sand. Overall, these results do not provide grounds for reducing the National Organic Program minimum fertilization-to-harvest interval from the current 120-day standard.

Arsenic removal from drinking water by a household sand filter in Vietnam--effect of filter usage practices on arsenic removal efficiency and microbiological water quality.

Science.gov (United States)

Nitzsche, Katja Sonja; Lan, Vi Mai; Trang, Pham Thi Kim; Viet, Pham Hung; Berg, Michael; Voegelin, Andreas; Planer-Friedrich, Britta; Zahoransky, Jan; Müller, Stefanie-Katharina; Byrne, James Martin; Schröder, Christian; Behrens, Sebastian; Kappler, Andreas

2015-01-01

Household sand filters are applied to treat arsenic- and iron-containing anoxic groundwater that is used as drinking water in rural areas of North Vietnam. These filters immobilize poisonous arsenic (As) via co-oxidation with Fe(II) and sorption to or co-precipitation with the formed Fe(III) (oxyhydr)oxides. However, information is lacking regarding the effect of the frequency and duration of filter use as well as of filter sand replacement on the residual As concentrations in the filtered water and on the presence of potentially pathogenic bacteria in the filtered and stored water. We therefore scrutinized a household sand filter with respect to As removal efficiency and the presence of fecal indicator bacteria in treated water as a function of filter operation before and after sand replacement. Quantification of As in the filtered water showed that periods of intense daily use followed by periods of non-use and even sand replacement did not significantly (psand replacement, CFUs of Escherichia coli of sand filters regarding As removal, but indicate a potential risk for human health arising from the enrichment of coliform bacteria during filtration and from E. coli cells that are introduced by sand replacement. Copyright © 2014 Elsevier B.V. All rights reserved.

The growth and photosynthesis of Typha in oil sands process affected material and water

Energy Technology Data Exchange (ETDEWEB)

Foote, L. [Alberta Univ., Edmonton, AB (Canada); Hornung, J. [Petro-Canada, Calgary, AB (Canada)

2007-07-01

Aquatic plants such as cattail contribute substantially to the energy flow in wetlands. Since Typha (cattail) plants acquire and cycle carbon and nutrients through wetlands, their growth and recycling of captured nutrients are an important part of natural, healthy wetland ecosystems. Cattail are pervasive and satisfy many of the criteria to be used as indicators of wetland integrity. This study investigated if cattail growth and carbon accrual were influenced by oil sands process materials (OSPM) such as consolidated tailings (CT). The purpose was to facilitate land reclamation initiatives by evaluating the impact that constituents of oil sands process material have on aquatic plant growth. The study was conducted at Suncor's experimental trenches. Six lined basins were used, of which 3 were filled with natural water and 3 were filled with trench water. Cattail were planted in different growth medium combinations, including CT over CT; soil over soil; soil over CT; and soil over sterilized sand. All leaf lengths and widths were measured along with the photosynthesis of the leaves and root and plant biomass at planting and after 2-years growth. A larger leaf area was observed under oil sands process influence, which may indicate increased carbon accrual above ground. Leaf area data suggested that CT affected plants are quite productive. The study also indicated that oil sands affected water may reduce plant fitness, and therefore could influence the overall oil sands reclamation timelines. Conversely, cattail grown in soil capped process affected material had a much larger leaf area compared to those grown in soil capped sand, most likely due to the higher levels of ammonia in process affected material.

Fish gill responses to pollutants from oil sands mining-associated waters

International Nuclear Information System (INIS)

Lee, L.E.J.; Willfang, S.; Lamb, M.P.; Nero, V.; Farwell, A.J.; Dixon, D.G.

2002-01-01

The processing of Athabasca Deposit oil sands results in large amounts of liquid wastes associated with oil sand tailings. In addition to containing polycyclic aromatic hydrocarbons (PAHs), these waste waters are high in salinity and naphthenic acids which may be toxic to aquatic biota and their effects must be clarified. This study presents a suite of tests for in-depth and quick analysis of tailings water toxicity and contributes to the assessment of environmental risk. Yellow perch, fathead minnows, and rainbow trout were exposed to reclamation ponds where both in vivo and in vitro evaluation of crude and individual naphthenic acids and salts were conducted to examine their effect on fish gills which are very susceptible to contaminants. The fish exposed to the reclamation ponds showed higher incidence of gill pathological changes than control fish in Mildred Lake, a reservoir lake whose waters are diverted for use in oil sands extraction. Notable gill histopathological changes were observed when fish were exposed in vivo to sulfate/chloride salts and to abietic acid. Changes in membrane integrity, lysosomal activity and general morphology were observed when fished were exposed in vitro to salts, commercial napthenic acids or crude naphthenic extracts from the reclamation ponds

Bitumen extraction from oil sands ore-water slurry using CaO (lime) and or ozone

Energy Technology Data Exchange (ETDEWEB)

Babadagli, T. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[Alberta Univ., Edmonton, AB (Canada); Burkus, Z.; Moschopedis, S.E.; Ozum, B. [Apex Engineering Inc., Calvert City, KY (United States)

2008-10-15

Reductions in the surface and interfacial tensions in oil sands ore-water slurry systems improve bitumen extraction processes from oil sands ore structures and promote the attachment of air bubbles to liberated bitumen droplets. This study provided details of a non-caustic bitumen extraction process where oil sands slurries were conditioned by bitumen asphaltenes modified to act as surfactants. Oil sands ore-water slurry extraction processes were optimized by adding lime (CaO) and oxidizing bitumen asphaltenes with ozone (O{sub 3}). Experiments were conducted using oil sands ore and process water samples from Alberta. Extraction tests were performed to investigate the effects of various CaO and O{sub 3} dosages and treatment retention times on bitumen extraction efficiency on operating temperatures of 20, 35 and 50 degrees C. A Dean-Stark extraction apparatus was used to determine the amount of bitumen contained in the ore, froth, and in left-over tailings. Process water and release water chemistry were also monitored. Bitumen extraction efficiency was defined as the percentage of bitumen recovered in the resulting froth. Use of the slurries allowed high extraction efficiencies at a temperature of 35 degrees C. Energy consumption and carbon dioxide (CO{sub 2}) emissions were also reduced. The study showed that both additions resulted in significant improvements in bitumen extraction efficiency. Use of the technique also eliminated the accumulation of Na{sup +} ions in produced water. It was concluded that further tests are needed in order to commercialize the CaO and O{sub 3} based techniques. 14 refs., 1 tab., 4 figs.

White Sands Missile Range 2011 Drinking Water Quality Report

Science.gov (United States)

2012-01-01

acerca de su agua potable . Haga que alguien lo traduzca para usted, o hable con alguien que lo entienda. Main Post White Sands Missile Range 2011...standards. What is This Water Quality Report? Este informe contiene informacion importante acerca de su agua potable . Haga que alguien lo traduzca

[Effect of shifting sand burial on evaporation reduction and salt restraint under saline water irrigation in extremely arid region].

Science.gov (United States)

Zhang, Jian-Guo; Zhao, Ying; Xu, Xin-Wen; Lei, Jia-Qiang; Li, Sheng-Yu; Wang, Yong-Dong

2014-05-01

The Taklimakan Desert Highway Shelterbelt is drip-irrigated with high saline groundwater (2.58-29.70 g x L(-1)), and shifting sand burial and water-salt stress are most common and serious problems in this region. So it is of great importance to study the effect of shifting sand burial on soil moisture evaporation, salt accumulation and their distribution for water saving, salinity restraint, and suitable utilization of local land and water resources. In this study, Micro-Lysimeters (MLS) were used to investigate dynamics of soil moisture and salt under different thicknesses of sand burial (1, 2, 3, 4, and 5 cm), and field control experiments of drip-irrigation were also carried out to investigate soil moisture and salt distribution under different thicknesses of shifting sand burial (5, 10, 15, 20, 25, 30, 35, and 40 cm). The soil daily and cumulative evaporation decreased with the increase of sand burial thickness in MLS, cumulative evaporation decreased by 2.5%-13.7% compared with control. And evaporative inhibiting efficiency increased with sand burial thickness, evaporative inhibiting efficiency of 1-5 cm sand burial was 16.7%-79.0%. Final soil moisture content beneath the interface of sand burial increased with sand burial thickness, and it increased by 2.5%-13.7% than control. The topsoil EC of shifting sand in MLS decreased by 1.19-6.00 mS x cm(-1) with the increasing sand burial thickness, whereas soil salt content beneath the interface in MLS increased and amplitude of the topsoil salt content was higher than that of the subsoil. Under drip-irrigation with saline groundwater, average soil moisture beneath the interface of shifting sand burial increased by 0.4% -2.0% compare with control, and the highest value of EC was 7.77 mS x cm(-1) when the sand burial thickness was 10 cm. The trend of salt accumulation content at shifting sand surface increased firstly, and then decreased with the increasing sand burial thickness. Soil salt contents beneath the

Phosphate and organic fertilizer recovery from black water

NARCIS (Netherlands)

Tervahauta, T.H.

2014-01-01

In this thesis the integration of treatment systems for black and grey water was investigated to improve resource recovery within source-separated sanitation concepts. Special focus was set on phosphate and organic fertilizer recovery from vacuum collected black water. Currently, the soil

Effects of pond fertilization on the physico-chemical water quality of ...

African Journals Online (AJOL)

The effect of fertilization on the physico-chemical water quality of six selected earthen fishponds in Ife North Local Government Area of Osun State was investigated for a period of two years sampling the ponds every other month. The fishponds were grouped with regard to fertilization practice and water flowage regime into ...

Potential of the application of the modified polysaccharides water solutions as binders of moulding sands

Directory of Open Access Journals (Sweden)

K. Kaczmarska

2015-10-01

Full Text Available The results of preliminary tests of selected properties of the moulding sands with the binder in the form of a 5 % water solution of the sodium salt of carboxymethyl starch (with a degree of substitution (DS of 0,2 and 0,87 arepresented in this study. The moulding sand properties such as permeability, abrasion resistance, tensile and bendingstrength - after curing - are shown in series of tests. The cure process was conducted in a field of electromagnetic radiation within the microwave range. The effect of the microwave treatment on the moulding sand was evaporating of water (solvent in a binder and cross-linking of the polymeric binder. As a result the cured moulding sands with particular properties, essential in the context of its application in the mould technology in the foundry industry, were obtained.

Nitrogen uptake and fertilizer nitrogen use efficiency of wheat under different soil water conditions

International Nuclear Information System (INIS)

Wang Baiqun; Zhang Wei; Yu Cunzu

1999-01-01

The pot experiment was conducted to study the effects of soil water regime and fertilizer nitrogen rate on the yields, nitrogen uptake and fertilizer nitrogen utilization of wheat by using 15 N tracer method. The results showed that the aboveground biomass, stem yield and grain yield increased with the increase of soil moisture in the fertilizer nitrogen treatments. All the yield increased with the increase of the fertilizer nitrogen rate in the soil water treatments. It was found that both soil water regime and fertilizer nitrogen rate significantly influenced the amount of nitrogen uptake by wheat according to the variance analysis. The amount of nitrogen uptake increased with the rise of the soil moisture in fertilizer nitrogen treatments and the amount also increased with the increase of the urea nitrogen rate in the soil water regime. Soil water regimes not only had an impact on nitrogen uptake but also had a close relationship with soil nitrogen supply and fertilizer nitrogen use efficiency. The soil A values decreased in urea treatment and increased with the rise of the soil moisture in the combination treatment of urea with pig manure. The fertilizer nitrogen use efficiency rose with the rise of the soil moisture in the same fertilizer nitrogen treatment. The fertilizer nitrogen use efficiency of the urea treatment was 13.3%, 27.9% and 32.3% in the soils with 50%, 70% and 90% of the field water capacity, respectively. The fertilizer nitrogen use efficiency in the combination treatment of urea with pig manure was 20.0%, 29.9% and 34.4% in the soils of above three levels, respectively. It was concluded that the low soil moisture restricted urea nitrogen use efficiency (UNUE) and the UNUE could be raised by combination treatment of urea with manure in the soil of enough moisture

Soil and water nitrate levels in relation to fertilizer utilization in Yugoslavia

International Nuclear Information System (INIS)

Filipovic, R.; Stevanovic, D.

1980-01-01

The results of a number of field experiments and monitoring of drainage canals close to intensive agricultural production involving the application of mineral fertilizers are reported. The object was to determine whether the pollution potential of underground and derived surface waters by nitrates and phosphates could be expressed as a function of the applied doses of fertilizer, method of application, climate, soil, etc. Analytical data indicated that, in surface waters adjacent to fertilized land, nitrate levels were higher than those of surface waters adjacent to unfertilized land. Preliminary results on the distribution of NO 3 down the soil profile following the application of 15 N-labelled ammonium nitrate to maize indicated downward movement of the labelled nitrate below the 100-cm depth. Application of organic matter with the fertilizer apparently retarded the leaching process. Soil-surface drainage water was characterized by high P/N ratios. (author)

Application of acoustical methods to the measurement of water content in sand

International Nuclear Information System (INIS)

Nazarov, V.E.; Radostin, A.V.; Stepanyants, Y.A.

2000-10-01

Results of laboratory experiments on the propagation of high-frequency acoustic waves (f = 100 kHz) in a glass tube, filled with river sand are presented. Several sand samples have been used with different water content: dry, unsaturated and completely water saturated. It is shown that the dissipative coefficient of acoustic waves decreases with increasing wave amplitude. This 'self-brightening' phenomenon takes place over the whole range of moisture content, from zero to 100%, but its degree of manifestation depends on the moisture content. The exponent of the dissipative nonlinearity α, is found to be the most sensitive parameter to the moisture content and is determined on the basis of measurements. It is considered to be a good indicator of water content in porous media and provides an opportunity to measure water content in such materials indirectly by means of an acoustic method. A simple phenomenological model is presented to explain the experimental results

Water repellency of clay, sand and organic soils in Finland

Directory of Open Access Journals (Sweden)

K. RASA

2008-12-01

Full Text Available Water repellency (WR delays soil wetting process, increases preferential flow and may give rise to surface runoff and consequent erosion. WR is commonly recognized in the soils of warm and temperate climates. To explore the occurrence of WR in soils in Finland, soil R index was studied on 12 sites of different soil types. The effects of soil management practice, vegetation age, soil moisture and drying temperature on WR were studied by a mini-infiltrometer with samples from depths of 0-5 and 5-10 cm. All studied sites exhibited WR (R index >1.95 at the time of sampling. WR increased as follows: sand (R = 1.8-5.0 < clay (R = 2.4-10.3 < organic (R = 7.9-undefined. At clay and sand, WR was generally higher at the soil surface and at the older sites (14 yr., where organic matter is accumulated. Below 41 vol. % water content these mineral soils were water repellent whereas organic soil exhibited WR even at saturation. These results show that soil WR also reduces water infiltration at the prevalent field moisture regime in the soils of boreal climate. The ageing of vegetation increases WR and on the other hand, cultivation reduces or hinders the development of WR.;

Research on the performance of sand-based environmental-friendly water permeable bricks

Science.gov (United States)

Cai, Runze; Mandula; Chai, Jinyi

2018-02-01

This paper examines the effects of the amount of admixture, the water cement ratio, the aggregate grading, and the cement aggregate ratio on the mechanical service properties and of porous concrete pavement bricks including strength, water permeability, frost resistance, and wear resistance. The admixture can enhance the performance of water permeable brick, and optimize the design mix. Experiments are conducted to determine the optimal mixing ratios which are given as; (1) the admixture (self-developed) within the content of 5% of the cement quality; (2) water-cement ratio equal to 0.34; (3) cement-aggregate ratio equal to 0.25; (4) fine aggregate of 70% (particle size 0.6-2.36mm); and coarse aggregate of 30% (particle size: 2.36-4.75mm). The experimental results that the sand-based permeable concrete pavement brick has a strength of 35.6MPa and that the water permeability coefficient is equal to 3.5×10-2cm/s. In addition, it was found that the concrete water permeable brick has good frost resistance and surface wear resistance, and that the its production costs are much lower than the similar sand-based water permeable bricks in China.

The influence of pore-water advection, benthic photosynthesis, and respiration on calcium carbonate dynamics in reef sands

NARCIS (Netherlands)

Rao, A.M.F.; Polerecky, L.; Ionescu, D.; Meysman, F.J.R.; de-Beer, D.

2012-01-01

To investigate diel calcium carbonate (CaCO₃) dynamics in permeable coral reef sands, we measured pore-water profiles and fluxes of oxygen (O₂), nutrients, pH, calcium (Ca²⁺), and alkalinity (TA) across the sediment-water interface in sands of different permeability

HYDRAULIC ELEVATOR INSTALLATION ESTIMATION FOR THE WATER SOURCE WELL SAND-PACK CLEANING UP

Directory of Open Access Journals (Sweden)

V. V. Ivashechkin

2016-01-01

Full Text Available The article offers design of a hydraulic elevator installation for cleaning up water-source wells of sand packs. It considerers the installation hydraulic circuit according to which the normal pump feeds the high-level tank water into the borehole through two parallel water lines. The water-jet line with washing nozzle for destroying the sand-pack and the supply pipe-line coupled with the operational nozzle of the hydraulic elevator containing the inlet and the supply pipelines for respectively intaking the hydromixture and removing it from the well. The paper adduces equations for fluid motion in the supply and the water-jet pipelines and offers expressions for evaluating the required heads in them. For determining water flow in the supply and the water-jet pipe lines the author proposes to employ graphical approach allowing finding the regime point in Q–H chart by means of building characteristics of the pump and the pipe-lines. For calculating the useful vertical head, supply and dimensions of the hydraulic elevator the article employs the equation of motion quantity with consistency admission of the motion quantity before and after mixing the flows in the hydraulic elevator. The suggested correlations for evaluating the hydraulic elevator efficiency determine the sand pack removal duration as function of its sizes and the ejected fluid flow rate. A hydraulic-elevator installation parameters estimation example illustrates removing a sand pack from a water-source borehole of 41 m deep and 150 mm diameter bored in the village of Uzla of Myadelsk region, of Minsk oblast. The working efficiency of a manufactured and laboratory tested engineering prototype of the hydraulic elevator installation was acknowledged in actual tests at the indicated borehole site. With application of graphical approach, the suggested for the hydraulic elevator installation parameters calculation procedure allows selecting, with given depth and the borehole diameter

A GIS-based fuzzy classification for mapping the agricultural soils for N-fertilizers use.

Science.gov (United States)

Assimakopoulos, J H; Kalivas, D P; Kollias, V J

2003-06-20

Special attention should be paid to the choice of the proper N-fertilizer, in order to avoid a further acidification and degradation of acid soils and at the same time to improve nitrogen use efficiency and to limit the nitrate pollution of the ground waters. Therefore, the risk of leaching of the fertilizer and of the acidification of the soils must be considered prior to any N-fertilizer application. The application of N-fertilizers to the soil requires a good knowledge of the soil-fertilizer relationship, which those who are planning the fertilization policy and/or applying it might not have. In this study, a fuzzy classification methodology is presented for mapping the agricultural soils according to the kind and the rate of application of N-fertilizer that should be used. The values of pH, clay, sand and carbonates soil variables are estimated at each point of an area by applying geostatistical techniques. Using the pH values three fuzzy sets: "no-risk-acidification"; "low-risk-acidification"; and "high-risk-acidification" are produced and the memberships of each point to the three sets are estimated. Additionally, from the clay and sand values the membership grade to the fuzzy set "risk-of-leaching" is calculated. The parameters and their values, which are used for the construction of the fuzzy sets, are based on the literature, the existing knowledge and the experimentation, of the soil-fertilizer relationships and provide a consistent mechanism for mapping the soils according to the type of N-fertilizers that should be applied and the rate of applications. The maps produced can easily be interpreted and used by non-experts in the application of the fertilization policy at national, local and farm level. The methodology is presented through a case study using data from the Amfilochia area, west Greece.

A novel waste water cleanup, fines sequestration and consolidation technology for oil sands applications

Energy Technology Data Exchange (ETDEWEB)

Soane, D.; Ware, W.; Mahoney, R.; Kincaid, P. [Soane Energy LLC, Cambridge, MA (United States)

2010-07-01

This paper discussed a wastewater technology designed to rapidly sequester suspended fines and other pollutants from the tailings produced during oil sands processes. The technology can also be used to clarify existing tailings ponds, and is expected to help address growing environmental concerns over the remediation of oil sands tailings. The ATA system is comprised of the following 3 components: (1) an activator polymer, (2) a tether polymer, and (3) an anchor particle. A small dose of the activator polymer is added to the fine or mature tailings, which then causes the suspended clay fines to aggregate. The anchor particles are then coated with the tether polymer. The anchor particle is formed from sand derived from coarser tailings. The tether-bearing anchor particles bind to the aggregated clay fines in the activated tailings to form robust complexes that can easily be separated from the waste stream. Output streams from the ATA process include a clean water stream that can be reused in oil sands extraction processes; and a dewatered solid that can be used as landfill as well as in construction and reclamation applications. The sensible heat retained in the recycled water is expected to also reduce the energy requirements of the oil sands extraction process. 6 refs., 1 tab., 5 figs.

Retention of radium from thermal waters on sand filters and adsorbents

Energy Technology Data Exchange (ETDEWEB)

Elejalde, C. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain)]. E-mail: inpelsac@bi.ehu.es; Herranz, M. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Legarda, F. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Romero, F. [Dpto. de Ingenieria Quimica y del Medio Ambiente, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Baeza, A. [Dpto. de Fisica, Facultad de Veterinaria, Universidad de Extremadura, Avda. Universidad s/n, 10071 Caceres (Spain)

2007-06-18

This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research.

Retention of radium from thermal waters on sand filters and adsorbents

International Nuclear Information System (INIS)

Elejalde, C.; Herranz, M.; Idoeta, R.; Legarda, F.; Romero, F.; Baeza, A.

2007-01-01

This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research

The effects of soil water conditions on nitrogen fertilization use efficiency

International Nuclear Information System (INIS)

Zhou Lingyun

1996-01-01

Concerning with applied nitrogen fertilizer, the uptake as well as loss of nitrogen is mainly related to soil water content. The effects of soil water condition in wheat field on the uptake, leach and loss of nitrogen fertilizer were studied using 15 N tracing technique. The results showed that within certain range of soil water supply, from 180 to 360 mm of available water storage, the loss of nitrogen was in direct proportion to the amount of fertilizer application and the nitrogen use efficiency decreased with the increase of nitrogen application. In other words, the nitrogen use efficiency descended with the nitrogen application increased in an order of 75 kgN/ha, 150 kgN/ha, 225 kgN/ha. One interesting result was that the nitrogen use efficiencies ranged from 17.0% to 30.5% for the treatments receiving the same application rate of 75 kgN/ha

Improving Water Use Efficiency of Lettuce (Lactuca sativa L.) Using Phosphorous Fertilizers.

Science.gov (United States)

Alkhader, Asad M F; Abu Rayyan, Azmi M

2013-01-01

A greenhouse pot experiment was conducted to evaluate the effect of phosphorous (P) fertilizers application to an alkaline calcareous soil on the water use efficiency (WUE) of lettuce cultivar "robinson" of iceberg type. Head fresh and dry weights, total water applied and WUE were affected significantly by the P fertilizer type and rate. P fertilizers addition induced a significant enhancement in the WUE and fresh and dry weights of the crop. A local phosphate rock (PR) applied directly was found to be inferior to the other types of P fertilizers (Mono ammonium phosphate (MAP), Single superphosphate (SSP), and Di ammonium phosphate ((DAP)). MAP fertilizer at 375 and 500 kg P2O5/ha application rates recorded the highest significant values of head fresh weight and WUE, respectively.

In vitro fertilization and sperm cryopreservation in the black-footed cat (Felis nigripes) and sand cat (Felis margarita).

Science.gov (United States)

Herrick, J R; Campbell, M; Levens, G; Moore, T; Benson, K; D'Agostino, J; West, G; Okeson, D M; Coke, R; Portacio, S C; Leiske, K; Kreider, C; Polumbo, P J; Swanson, W F

2010-03-01

Studies of in vitro fertilization (IVF) and sperm cryopreservation have been conducted in several small cat species, but virtually no data exist for black-footed cats (Felis nigripes) (BFCs) or sand cats (Felis margarita) (SCs). The objectives of this study were 1) to compare in vitro motility and acrosome status of fresh and cryopreserved (frozen in pellets on dry ice or in straws in liquid nitrogen vapor) BFC and SC spermatozoa cultured in feline-optimized culture medium (FOCM) or Ham F-10, 2) to assess ovarian responsiveness in BFCs and SCs following exogenous gonadotropin treatment and laparoscopic oocyte recovery, and 3) to evaluate the fertility of fresh and frozen-thawed spermatozoa from both species using homologous and heterologous (domestic cat oocytes) IVF in the two culture media. Motility and acrosomal integrity of fresh and frozen-thawed spermatozoa from BFCs and SCs were similar (P > 0.05) in both media during 6 h of culture. Although effects were more pronounced in SCs, cryopreservation in straws was superior (P 80% of recovered oocytes were of optimal (grade 1) quality. The BFC and SC spermatozoa fertilized 60.0%-79.4% of homologous and 37.7%-42.7% of heterologous oocytes in both culture media, with increased (P < 0.05) cleavage of homologous (SC) and heterologous (BFC and SC) oocytes in FOCM. These results provide the first information to date on the gamete biology of two imperiled cat species and further our capacity to apply reproductive technologies for their conservation.

Stream water chemistry after two forest fertilizations with Skog Vital in central Sweden

International Nuclear Information System (INIS)

Ring, E.; Nohrstedt, H.Oe.

1993-05-01

A study was made of the impact of forest fertilization (non-nitrogenous mix) on the water chemistry of two streams, which drain catchment areas in east Haerjedalen in Sweden. In summer 1990, part of one of the catchment areas was fertilized by tractor at a dose of 0.6 tonnes per hectare, and part of the other by helicopter at a dose of 0.5 tonnes per hectare. The fertilizer contained base cations, sulphur, phosphorus, zinc and boron. Water samples were taken at a water-sampling station upstream of the treated area and at a water-sampling station downstream of the treated area. A total of 30 samples were made and the water was analysed for pH, alkalinity, nitrogen, phosphorus, base cations, aluminium and sulphate. Discharge was both measured and simulated, the latter using a runoff model. An estimate was made of the additional leaching resulting from fertilization. 13 refs, 12 figs, 6 tabs

Moisture diffusion coefficients determination of furan bonded sands and water based foundry coatings

DEFF Research Database (Denmark)

Di Muoio, Giovanni Luca; Tiedje, Niels Skat

2016-01-01

Moisture content in furan bonded sand and water based coatings can be one of the main causes for gas related defects in large cast iron parts. Moisture diffusion coefficients for these materials are needed to precisely predict the possible moisture levels in foundry moulds. In this study, we first...... provide an example on how it is possible to apply this knowledge to estimate moisture variation in a sand mould during production....

Nitrogen-isotope ratios of nitrate in ground water under fertilized fields, Long Island, New York

Science.gov (United States)

Flipse, W.J.; Bonner, F.T.

1985-01-01

Ground-water samples from two heavily fertilized sites in Suffolk County, New York, were collected through the 1978 growing season and analyzed for nitrate-N concentrations and nitrogen-isotope ratios. Six wells were at a potato farm; six were on a golf course. The purpose of this study was to determine whether the 15N/14N ratios (??15N values) of fertilizer are increased during transit from land surface to ground water to an extent which would preclude use of this ratio to distinguish agricultural from animal sources of nitrate in ground water. Ground water at both sites contained a greater proportion of 15N than the fertilizers being applied. At the potato farm, the average ??15N value of the fertilizers was 0.2???; the average ??15N value of the ground-water nitrate was 6.2???. At the golf course, the average ??15N value of the fertilizers was -5.9???, and that of ground-water nitrate was 6.5???. The higher ??15N values of ground-water nitrate are probably caused by isotopic fractionation during the volatile loss of ammonia from nitrogen applied in reduced forms (NH4+ and organic-N). The ??15N values of most ground-water samples from both areas were less than 10???, the upper limit of the range characteristic of agricultural sources of nitrate; these sources include both fertilizer nitrate and nitrate derived from increased mineralization of soil nitrogen through cultivation. Previous studies have shown that the ??15N values of nitrate derived from human or animal waste generally exceed 10???. The nitrogen-isotope ratios of fertilizer-derived nitrate were not altered to an extent that would make them indistinguishable from animal-waste-derived nitrates in ground water.Ground-water samples from two heavily fertilized sites in Suffolk County, New York, were collected through the 1978 growing season and analyzed for nitrate-N concentrations and nitrogen-isotope ratios. Six wells were at a potato farm; six were on a golf course. The purpose of this study was to

Quantifying the Effect of Soil Water Repellency on Infiltration Parameters Using a Dry Sand

Science.gov (United States)

Shillito, R.; Berli, M.; Ghezzehei, T. A.; Kaminski, E.

2017-12-01

Water infiltration into less than perfectly wettable soils has usually been considered an exceptional case—in fact, it may be the rule. Infiltration into soils exhibiting some degree of water repellency has important implications in agricultural irrigation, post-fire runoff, golf course and landscape management, and spill and contaminant mitigation. Beginning from fundamental principles, we developed a physically-based model to quantify the effect of water repellency on infiltration parameters. Experimentally, we used a dry silica sand and treated it to achieve various known degrees of water repellency. The model was verified using data gathered from multiple upward infiltration (wicking) experiments using the treated sand. The model also allowed us to explore the effect of initial soil moisture conditions on infiltration into water-repellent soils, and the physical interpretation of the simple water drop penetration time test. These results provide a fundamental step in the physically-based understanding of how water infiltrates into a less than perfectly wettable porous media.

Field trials show the fertilizer value of nitrogen in irrigation water

Directory of Open Access Journals (Sweden)

Mike Cahn

2017-04-01

Full Text Available Increased regulatory activity designed to protect groundwater from degradation by nitrate-nitrogen (NO3-N is focusing attention on the efficiency of agricultural use of nitrogen (N. One area drawing scrutiny is the way in which growers consider the NO3-N concentration of irrigation water when determining N fertilizer rates. Four drip-irrigated field studies were conducted in the Salinas Valley evaluating the impact of irrigation water NO3-N concentration and irrigation efficiency on the N uptake efficiency of lettuce and broccoli crops. Irrigation with water NO3-N concentrations from 2 to 45 milligrams per liter were compared with periodic fertigation of N fertilizer. The effect of irrigation efficiency was determined by comparing an efficient (110% to 120% of crop evapotranspiration, ETc and an inefficient (160% to 200% of ETc irrigation treatment. Across these trials, NO3-N from irrigation water was at least as efficiently used as fertilizer N; the uptake efficiency of irrigation water NO3-N averaged approximately 80%, and it was not affected by NO3-N concentration or irrigation efficiency.

Water Footprint in Nitrate Vulnerable Zones: Mineral vs. Organic Fertilization.

Science.gov (United States)

Castellanos Serrano, María Teresa; Requejo Mariscal, María Isabel; Villena Gordo, Raquel; Cartagena Causapé, María Carmen; Arce Martínez, Augusto; Ribas Elcorobarrutia, Francisco; María Tarquis Alfonso, Ana

2017-04-01

In intensive agriculture, it is necessary to apply irrigation and fertilizers to increase the crop yield. An optimization of water and N application is necessary. An excess of irrigation implies nitrates washing which would contribute to the contamination of the groundwater. An excess of N, besides affecting the yield and fruit quality, causes serious environmental problems. Nitrate vulnerable zones (NVZs) are areas designated as being at risk from agricultural nitrate pollution. They include around 16% of land in Spain and in Castilla-La Mancha, the area studied, represents 45% of the total land. In several zones, the N content of the groundwater could be approximately 140 mg L-1, or even higher [1]. The input of nitrogen fertilizers (mineral or organic), applied with a poor management, could be increased considerably the pollution risks. The water footprint (WF) is as indicator for the total volume of direct and indirect freshwater used, consumed and/or polluted [2]. The WF includes both consumptive water use: blue water (volume of surface and groundwater consumed) and green water (rainwater consumed)). A third element is the water required to assimilate pollution (grey water) [2]. Under semiarid conditions with low irrigation water quality, green WF is zero because the effective rainfall is negligible. Blue WF includes: i) extra consumption or irrigation water that the farmer has to apply to compensate the fail of uniformity on discharge of drips, ii) percolation out of control or salts leaching, which depends on the salt tolerance of the crop, soil and quality of irrigation water, to ensure the fruit yield. In the NVZs, the major concern is grey WF, because the irrigation and nitrogen dose have to be adjusted to the crop needs in order to minimize nitrate pollution. This study focus on the assessment of mineral and organic fertilization on WF in a fertirrigated melon crop under semiarid conditions with a low water quality. During successive years, a melon crop

Impact of water-fertilizer interaction on yields of crops

International Nuclear Information System (INIS)

Kahlown, M.A.; Iqbal, M.; Junejo, M.R.; Ghaffar, A.

2002-01-01

Water-fertilizer interaction was studied on wheat and cotton during crop seasons of 1995 to 1998 in the Fordwah Eastern Sadiqia (south), Irrigation and Drainage Project. Irrigation levels applied included 0.75, 1.00 and 1.25 times the evapotranspiration (ET), while fertilizer doses were 75, 100 and 125 percent of recommendations of NPK for district Bahawalnagar. The experiment was conducted at four different locations of the project, where soil was medium textured, free from salinity/alkalinity and sufficiently drained, with water table in the range of 2-3m from the soil surface. Wheat variety Inqalab-91 and cotton variety CLM-109 were sown at their recommended time of sowing, seed rate and management practices. Irrigation was applied in consideration of open-pan evaporation and crop co-efficient for the respective crop, when sum total of the products of pan-evaporation and KC values reached 7.5 cm. Irrigation was applied to all the plots according to treatment allowance, i.e. , with 25 percent cut and addition to .75 and 1.25 Et levels, respectively. The results indicated that irrigation levels had non-significant effect on wheat and cotton yields. The results clearly negate the concept of heavy irrigation, generally exercised by our farming community. Light irrigation as a results of 0.75 Et indication were equally effective: rather, these were economical and efficient under the scarce water availability. Fertilizer had somewhat significant response. Irrigation and fertilizer did not exhibit much significant interaction. In case of wheat, the two inputs were independent, while cotton had significant inter-dependence of the two variables. The experiment gave the conclusion that both wheat and cotton crops should be applied lighter irrigation and NPK fertilizer must be applied in compliance to recommendations, for efficient and economical use of the available crop-production resources. (author)

Efficiency of water and fertilizer use in semi-arid regions

International Nuclear Information System (INIS)

1976-01-01

The proceedings contain 14 papers considering problems on soil and soil water, irrigation, and the use of fertilizers in semi-arid zones. Research projects in these fields are discussed and results obtained so far are reported (tables and diagrams on the behaviour of water and fertilizers in soils). The use of radioisotope techniques is mentioned briefly. Finally, some future ''first priority'' research areas are identified and recommendations for further research programs are given. These programs aim at reducing the hazards of crop failure and at increasing production under dry farming conditions

Revegetation and management of tailings sand slopes from tar sand extraction: 1978 results

Energy Technology Data Exchange (ETDEWEB)

Rowell, M J

1979-01-01

The results are reported of research into the revegetation of two areas on a steeply sloping dike composed of tailings sand from tar sand extraction at the Great Canadian Oil Sand Limited plant at Fort McMurray, Alberta. One area was seeded with three pasture grasses and two legumes in 1971 after the slope surface had been mixed with peat to a depth of 15 cm. A second area had been amended with peat or peat and overburden and differing rates of fertilizer added. A mix containing nine grasses, four legumes, and oats, as a companion crop, was seeded in July 1976. The objectives of the research were to study methods for the establishment of a stable vegetative cover that would prevent erosion of the slope and, in time, might become a self maintaining unit. Tillage of soil amendments to a depth of 15 cm and 30 cm were compared in promoting deeper rooting and stabilizing of the slope.

Oil sands tailings management project

Energy Technology Data Exchange (ETDEWEB)

Godwalt, C. [Alberta WaterSMART, Calgary, AB (Canada); Kotecha, P. [Suncor Energy Inc, Calgary, AB (Canada); Aumann, C. [Alberta Innovates - Technology Futures, Alberta Governement, AB (Canada)

2010-11-15

The Oil sands leadership initiative (OSLI) works with the Government of Alberta on the development of the oil sands industry, considering environmental, economical and social aspects. Water management was identified as one of most important areas to focus on. Alberta WaterSMART was requested to support the development and the management of projects resulting from the work done or underway in this field. The development of a regional water management solution stood out as the most interesting solution to obtain significant results. In the Athabasca Region, oil sands producers work independently on their water sourcing and disposal with particular attention to fresh water conservation and economics. The Athabasca River represents a source for mines and distant saline aquifers are the target of steam assisted gravity drainage (SAGD) operators. As part of a four-phase project aiming to study the environmental and economic footprint (EEF) benefit of alternatives for Athabasca oil sands production water supply and disposal, the purpose of the tailings water management project was to identify tailings treatment technologies that are ready to be implemented, and to design and evaluate solutions in order to improve regional oil sands production water sourcing and disposal. Alternatives were evaluated based on their total EEF, applying a lifecycle assessment methodology with a particular attention on the quantification of important performance indicators. 25 refs., 8 tabs., 40 figs.

Oil sands tailings management project

International Nuclear Information System (INIS)

Godwalt, C.; Kotecha, P.; Aumann, C.

2010-11-01

The Oil sands leadership initiative (OSLI) works with the Government of Alberta on the development of the oil sands industry, considering environmental, economical and social aspects. Water management was identified as one of most important areas to focus on. Alberta WaterSMART was requested to support the development and the management of projects resulting from the work done or underway in this field. The development of a regional water management solution stood out as the most interesting solution to obtain significant results. In the Athabasca Region, oil sands producers work independently on their water sourcing and disposal with particular attention to fresh water conservation and economics. The Athabasca River represents a source for mines and distant saline aquifers are the target of steam assisted gravity drainage (SAGD) operators. As part of a four-phase project aiming to study the environmental and economic footprint (EEF) benefit of alternatives for Athabasca oil sands production water supply and disposal, the purpose of the tailings water management project was to identify tailings treatment technologies that are ready to be implemented, and to design and evaluate solutions in order to improve regional oil sands production water sourcing and disposal. Alternatives were evaluated based on their total EEF, applying a lifecycle assessment methodology with a particular attention on the quantification of important performance indicators. 25 refs., 8 tabs., 40 figs.

Effect of organic fertilizers derived dissolved organic matter on pesticide sorption and leaching

Energy Technology Data Exchange (ETDEWEB)

Li Kun [Department of Plant, Soil, and Insect Sciences, Stockbridge Hall, University of Massachusetts, Amherst, MA 01003 (United States); Xing Baoshan [Department of Plant, Soil, and Insect Sciences, Stockbridge Hall, University of Massachusetts, Amherst, MA 01003 (United States) and Northeast Institute of Geography and Agro-ecology, CAS, Harbin 150040 (China)]. E-mail: bx@pssci.umass.edu; Torello, William A. [Department of Plant, Soil, and Insect Sciences, Stockbridge Hall, University of Massachusetts, Amherst, MA 01003 (United States)

2005-03-01

Incorporation of organic fertilizers/amendments has been, and continues to be, a popular strategy for golf course turfgrass management. Dissolved organic matter (DOM) derived from these organic materials may, however, facilitate organic chemical movement through soils. A batch equilibrium technique was used to evaluate the effects of organic fertilizer-derived DOM on sorption of three organic chemicals (2,4-D, naphthalene and chlorpyrifos) in USGA (United States Golf Association) sand, a mixed soil (70% USGA sand and 30% native soil) and a silt loam soil (Typic Fragiochrept). DOM was extracted from two commercial organic fertilizers. Column leaching experiments were also performed using USGA sand. Sorption experiments showed that sorption capacity was significantly reduced with increasing DOM concentration in solution for all three chemicals. Column experimental results were consistent with batch equilibrium data. These results suggest that organic fertilizer-derived DOM might lead to enhanced transport of applied chemicals in turf soils. - Dissolved organic matter could result in enhanced transport of chemicals applied to turf.

Effect of organic fertilizers derived dissolved organic matter on pesticide sorption and leaching

International Nuclear Information System (INIS)

Li Kun; Xing Baoshan; Torello, William A.

2005-01-01

Incorporation of organic fertilizers/amendments has been, and continues to be, a popular strategy for golf course turfgrass management. Dissolved organic matter (DOM) derived from these organic materials may, however, facilitate organic chemical movement through soils. A batch equilibrium technique was used to evaluate the effects of organic fertilizer-derived DOM on sorption of three organic chemicals (2,4-D, naphthalene and chlorpyrifos) in USGA (United States Golf Association) sand, a mixed soil (70% USGA sand and 30% native soil) and a silt loam soil (Typic Fragiochrept). DOM was extracted from two commercial organic fertilizers. Column leaching experiments were also performed using USGA sand. Sorption experiments showed that sorption capacity was significantly reduced with increasing DOM concentration in solution for all three chemicals. Column experimental results were consistent with batch equilibrium data. These results suggest that organic fertilizer-derived DOM might lead to enhanced transport of applied chemicals in turf soils. - Dissolved organic matter could result in enhanced transport of chemicals applied to turf

Copper deficiency can limit nitrification in biological rapid sand filters for drinking water production

DEFF Research Database (Denmark)

Wagner, Florian Benedikt; Nielsen, Peter Borch; Boe-Hansen, Rasmus

2016-01-01

Incomplete nitrification in biological filters during drinking water treatment is problematic, as it compromises drinking water quality. Nitrification problems can be caused by a lack of nutrients for the nitrifying microorganisms. Since copper is an important element in one of the essential...... enzymes in nitrification, we investigated the effect of copper dosing on nitrification in different biological rapid sand filters treating groundwater. A lab-scale column assay with filter material from a water works demonstrated that addition of a trace metal mixture, including copper, increased ammonium...... to the bulk phase. Overall, copper dosing to poorly performing biological rapid sand filters increased ammonium removal rates significantly, achieving effluent concentrations of below 0.01 mg NH4-N L-1, and had a long-term effect on nitrification performance....

The future of water quality and the regulatory environment for the oil sands and coalbed methane development

International Nuclear Information System (INIS)

Kasperski, K.; Mikula, R.

2004-01-01

The use of consolidated tailings in recent years for the surface mined oil sands bitumen extraction process has resulted in major improvements in water consumption because materials are transported more efficiently in a slurry form. Water storage requirements will be reduced as the cost of handling tailings in the conventional manner becomes clearer. Future improvements may be in the form of mine face sand rejection, more advanced tailings treatment, or the use of clays for continuous reclamation. Sand filtering or stacking technologies can improve tailings properties and reduce the amount of water needed per unit of bitumen. It was noted that although the technologies will minimize land disturbance and fresh water consumption, water chemistries will be driven to the point where extraction recovery is impaired and water treatment will be required. The volumes and quality of water that is pumped out to produce coalbed methane (CBM) was also discussed with reference to the origin of water in coal beds, water resource depletion, water disposal, direct land applications, and surface evaporation. The Alberta Energy and Utilities Board and Alberta Environment are responsible for regulating CBM water issues in the province, including water disposal from CBM production. 41 refs., 6 tabs., 8 figs

Does water harvesting induce fertilizer use among smallholders? Evidence from Ethiopia

NARCIS (Netherlands)

Wakeyo, M.B.; Gardebroek, C.

2013-01-01

Rainfall shortage is a major production risk for smallholder farmers. Due to rainfall shortage, smallholders limit the use of modern inputs such as fertilizer and improved seeds. This study investigates if water harvesting technologies (WHTs) induce fertilizer use and whether there is joint adoption

Evaluating regional water scarcity: Irrigated crop water budgets for groundwater management in the Wisconsin Central Sands

Science.gov (United States)

Nocco, M. A.; Kucharik, C. J.; Kraft, G.

2013-12-01

Regional water scarcity dilemmas between agricultural and aquatic land users pervade the humid northern lake states of Wisconsin, Minnesota, and Michigan, where agricultural irrigation relies on groundwater drawn from shallow aquifers. As these aquifers have strong connectivity to surface waters, irrigation lowers water levels in lakes and wetlands and reduces stream discharges. Irrigation expansion has cultivated a 60-year water scarcity dilemma in The Wisconsin Central Sands, the largest irrigated region in the humid northern lake states, dedicated to potato, maize, and processing vegetable production. Irrigation has depleted Wisconsin Central Sands surface waters, lowering levels in some lakes by over 2 m and drying some coldwater trout streams. Aquatic ecosystems, property values, and recreational uses in some surface waters have been devastated. While the causal link between pumping and surface water stress is established, understanding crop-mediated processes, such as the timing and magnitude of groundwater consumption by evapotranspiration (ET) and groundwater recharge, will be useful in management of groundwater, irrigated cropping systems, and surface water health. Previous modeling and field efforts have compared irrigated crop water use to a natural reference condition on a net annual basis. As a result, we presently understand that for irrigated potatoes and maize, the average annual ET is greater and therefore, the average annual recharge is less than rainfed row crops, grasslands, and both coniferous and deciduous forests. However, we have a limited understanding of the magnitude and timing of ET and recharge from irrigated cropping systems on shorter time scales that proceed with the annual cropping cycle (i.e. planting, full canopy, harvest, residue cover). We seek to understand the spatiotemporal variability of crop water budgets and associated water scarcity in the Wisconsin Central Sands through detailed measurements of drainage (potential

Sand consolidation

Energy Technology Data Exchange (ETDEWEB)

Spain, H H

1965-01-21

In a sand consolidation method in which there is injected a mixture of resin-forming liquids comprising an aryl-hydroxy low molecular weight compound, a water- soluble aldehyde, and a catalyst, an improvement is claimed which comprises diluting the resin-forming liquids with a diluent and with water so that the yield of the resin is sufficient to consolidate the sand particles with the minimum desirable pressure. The diluent may be mutually soluble in water and in the resin-forming liquids, and does not affect the setting time of the polymer. The aldehyde and the aryl-hydroxy compound may be in ratio of 5:1, and the diluent, methyl alcohol, is present in a ratio of 2:1 with reference to the water.

Ground-water flow and quality in the Atlantic City 800-foot sand, New Jersey

Science.gov (United States)

McAuley, Steven D.; Barringer, Julia L.; Paulachok, Gary N.; Clark, Jeffrey S.; Zapecza, Otto S.

2001-01-01

The regional, confined Atlantic City 800-foot sand is the principal source of water supply for coastal communities of southern New Jersey. In response to extensive use of the aquifer--nearly 21 million gallons per day in 1986--water levels have declined to about 100 feet below sea level near Atlantic City and remain below sea level throughout the coastal areas of southern New Jersey, raising concerns about the potential for saltwater intrusion into well fields. Water levels in the Atlantic City 800-foot sand have declined in response to pumping from the aquifer since the 1890's. Water levels in the first wells drilled into the Atlantic City 800-foot sand were above land surface, and water flowed continuously from the wells. By 1986, water levels were below sea level throughout most of the coastal areas. Under current conditions, wells near the coast derive most of their supply from lateral flow contributed from the unconfined part of the aquifer northwest of the updip limit of the confining unit that overlies the Atlantic City 800- foot sand. Ground water also flows laterally from offshore areas and leaks vertically through the overlying and underlying confining units into the Atlantic City 800-foot sand. The decline in water levels upsets the historical equilibrium between freshwater and ancient saltwater in offshore parts of the aquifer and permits the lateral movement of saltwater toward pumping centers. The rate of movement is accelerated as the decline in water levels increases. The chloride concentration of aquifer water 5.3 miles offshore of Atlantic City was measured as 77 mg/L (milligrams per liter) in 1985 at a U.S. Geological Survey observation well. Salty water has also moved toward wells in Cape May County. The confined, regional nature of the Atlantic City 800-foot sand permits water levels in Cape May County to decline in response to pumping in Atlantic County and vice versa. Historically, chloride concentrations as great as 1 ,510 mg/L have been

Impacts of oil sands process water on fen plants: Implications for plant selection in required reclamation projects

International Nuclear Information System (INIS)

Pouliot, Rémy; Rochefort, Line; Graf, Martha D.

2012-01-01

Fen plant growth in peat contaminated with groundwater discharges of oil sands process water (OSPW) was assessed in a greenhouse over two growing seasons. Three treatments (non-diluted OSPW, diluted OSPW and rainwater) were tested on five vascular plants and four mosses. All vascular plants tested can grow in salinity and naphthenic acids levels currently produced by oil sands activity in northwestern Canada. No stress sign was observed after both seasons. Because of plant characteristics, Carex species (C. atherodes and C. utriculata) and Triglochin maritima would be more useful for rapidly restoring vegetation and creating a new peat-accumulating system. Groundwater discharge of OSPW proved detrimental to mosses under dry conditions and ensuring adequate water levels would be crucial in fen creation following oil sands exploitation. Campylium stellatum would be the best choice to grow in contaminated areas and Bryum pseudotriquetrum might be interesting as it has spontaneously regenerated in all treatments. - Highlights: ► Fen plant growth was assessed under groundwater discharges of oil sands process water. ► Sedge and grass species were not stressed after two growing seasons in greenhouse. ► Carex species and Triglochin maritima would be helpful in created contaminated fens. ► In dry conditions, contaminated groundwater discharge was detrimental for mosses. ► Campylium stellatum would be the best choice in created fens with contaminated water. - Sedges and grasses tolerated the contact with oil sands process water and could probably grow well in contaminated created fens, but mosses were particularly affected under dry conditions.

Effect of hardening methods of moulding sands with water glass on structure of bonding bridges

Directory of Open Access Journals (Sweden)

M. Stachowicz

2010-07-01

Full Text Available Research on influence of hardening methods on structure of bonding bridges in moulding sands with sodium water glass is presented.Moulding sands with addition of 2.5 % of binder with molar module 2.0 were hardened with CO2 and dried in traditional way or hardenedwith microwaves. It was proved that the hardening method affects structure of bonding bridges, correlating with properties of the hardened moulding sands. It was found that strength of the moulding sands hardened with microwaves for 4 min is very close to that measured after traditional drying at 110 °C for 120 min. So, application of microwave hardening ensures significant shortening of the process time to the value comparable with CO2 hardening but guaranteeing over 10-fold increase of mechanical properties. Analysis of SEM images of hardened moulding sands permitted explaining differences in quality parameters of moulding sands by connecting them with structure of the created bonding bridges.

Radium and uranium in phosphate fertilizers and their impact on the radioactivity of waters

International Nuclear Information System (INIS)

Barisic, D.; Lulic, S.; Miletic, P.

1992-01-01

The study of radioactivity in the phosphate fertilizers and water ways of the Kanovci area was performed in order to determine the influence of the application of phosphate fertilizers on the radioactive pollution of these waters. The activity of 226 Ra, 228 Ra, 235 U and 238 U was measured in different types of phosphate fertilizers and waters by means of γ-ray spectrometry. Surface water, water from drainage channels, shallow groundwater and deep groundwater samples were collected from the Kanovci agricultural and well field area in Eastern Slavonia, where phosphate fertilizers have been used for the past 15 years. 137 Cs was also measured in water samples. The typical phosphate fertilizer used in the Kanovci area contains 75 Bq kg -1 of 226 Ra, 9 Bq kg -1 of 228 Ra, 52 Bq kg -1 of 235 U and 1120 Bq kg -1 of 238 U. The estimated annual deposition of uranium and radium in soils of the agricultural and well field area in Kanovci is: 4.5 Bq m -2 for 226 Ra, 0.5 Bq m -2 for 228 Ra, 3.1 Bq m -2 for 235 U and 67 Bq m -2 for 238 U. The greatest concentrations of both uranium isotopes are measured in water from drainage channels with a mean value of 120 Bq m -3 for 238 U and 5.5 Bq m -3 for 235 U. The concentrations of both radium isotopes generally increase with depth of water as distinct from uranium, whose concentrations in deep groundwater are much lower. The highest concentrations of 137 Cs were measured in water from drainage channels; it was not detected in deep groundwater. The 238 U/ 226 Ra activity ratio (AR) is the highest in water from drainage channels and the Bosut River, while in deep groundwater the ratio is only 1.6. Results indicate that high uranium concentrations in surface water, shallow groundwater and water from drainage channels are caused by phosphate fertilizer application in agriculture on the Kanovci area. (author)

Radon diffusion studies in air, gravel, sand, soil and water

International Nuclear Information System (INIS)

Singh, B.; Singh, S.; Virk, H.S.

1993-01-01

Radon isotopes are practically inert and have properties of gases under conditions of geological interest. During their brief lives their atoms are capable of moving from sites of their generation. Radon diffusion studies were carried out in air, gravel, sand, soil and water using silicon diffused junction electronic detector, Alphameter-400. Diffusion constant and diffusion length is calculated for all these materials. (author)

Nickel removal from nickel plating waste water using a biologically active moving-bed sand filter.

Science.gov (United States)

Pümpel, Thomas; Macaskie, Lynne E; Finlay, John A; Diels, Ludo; Tsezos, Marios

2003-12-01

Efficient removal of dissolved nickel was observed in a biologically active moving-bed 'MERESAFIN' sand filter treating rinsing water from an electroless nickel plating plant. Although nickel is fully soluble in this waste water, its passage through the sand filter promoted rapid removal of approximately 1 mg Ni/l. The speciation of Ni in the waste water was modelled; the most probable precipitates forming under the conditions in the filter were predicted using PHREEQC. Analyses of the Ni-containing biosludge using chemical, electron microscopical and X-ray spectroscopic techniques confirmed crystallisation of nickel phosphate as arupite (Ni3(PO4)2 x 8H2O), together with hydroxyapatite within the bacterial biofilm on the filter sand grains. Biosorption contributed less than 1% of the overall sequestered nickel. Metabolising bacteria are essential for the process; the definitive role of specific components of the mixed population is undefined but the increase in pH promoted by metabolic activity of some microbial components is likely to promote nickel desolubilisation by others.

Investigating salt and naphthenic acids interactions in the toxicity of oil sands process water to freshwater invertebrates

International Nuclear Information System (INIS)

Turcotte, D.; Kautzman, M.; Wojnarowicz, P.; Cutter, J.; Bird, E.; Liber, K.

2010-01-01

The hot water extraction process used to produce bitumens from oil sands produces a large volume of oil sands process water (OSPW) that contain elevated concentrations of naphthenic acids (NA) and salts. Many oil sands reclamation projects are proposing the use of OSPW as part of reconstructed wetlands projects. This study investigated the toxicity of OSPW to freshwater invertebrates. The toxic interactions between NA and salinity on freshwater invertebrates were assessed. Bioassays with laboratory-cultured Ceriodaphnia dubia were conducted to determine the toxicity of OSPW from selected water bodies. The study showed that while the concentrations of NAs and salinity were elevated in OSPW waters that caused toxic responses, the concentrations of salinity ions varied greatly among the OSPW samples. Results of the study suggested that ion composition may be a factor in toxicity. Interactions between NAs and salinity were then assessed by performing bioassays with mixtures representing major ion combinations in OSPW.

Evaluation of the MF/UF Performance for the Reuse of Sand Filter Backwash Water from Drinking Water Treatment Plants

Directory of Open Access Journals (Sweden)

Neda Shirzadi

2015-05-01

Full Text Available The aim of this study was to investigate the application of micro-filtration and ultra-filtration membrane systems in order to improve the physical and microbial quality and the reuse of backwash water from the sand filter units in water treatment plants. The backwash water from filters makes up for 3 to 5 percent of the total water treated, which is disposed in most WTPs. However, the treatment and reuse of the backwash water is more admissible from technical and economic viewpoints, especially in view of the present water scarcity. For the purposes of this study, use was made of membrane modules of micro- and ultra-filters on a pilot scale. The micro-filter employed consisted of a polypropylene membrane module with a porosity of 1 micron in size and a fiberglass module with a porosity of 5 microns. The ultra-filter was made of PVC hollow fiber with a molecular weight of 100,000 Dalton. In order to feed the two pilots, backwash water from a sand filter was collected from one of the WTPs in Tehran. After samples were taken from the backwash water, the physical and microbial removal efficiency was periodically evaluated based on the standard method and the micro-filtration, ultra-filtration, and combined MF/UF processes were compared with respect to their performance. The results indicate that the combined MF/UF process is able to decrease turbidity, MPN, COD, TSS, and Fe with efficiency values of 99.9, 100, 61.5, 99.9 and 98.8 percent, respectively. Overall, the findings confirmed the technical capabilities of this method for the recovery and reuse of the effluent produced in the backwashing mechanism of sand filters in WTPs.

Effect of Phosphorus Fertilizer and Water Stress on Protein and Phenolic Contents in Cotton (Gossypium Hirsutum L.)

International Nuclear Information System (INIS)

Abbas, Z.; Muhammad, S.; Murtaza, G.; Ahmad, I.; Shakeel, A.; Islam, M.; Ahmad, M.; Abdullah, M.

2015-01-01

Crop quality and production are affected by various fertilizers and water stress. In present research, the response of cotton variety CIM-496 to water stress and phosphorus fertilizer was investigated. Samples were collected after 90 days of planting. Kjeldahl method and thin layer chromatography (TLC) were used for the quantitative and qualitative analysis of total protein and phenolic compounds, respectively. Proteins were greatly affected by fertilizer treatment and water stress, but phenolic compounds remained unchanged upon fertilizer treatment. However, they were greatly affected by irrigation and water stress. Crop treated with 100 kg ha/sup -1/ P/sub 2/O/sub 5/ under water stress maintained high protein content as compared to unfertilized and no water stress treatments. However, phenolic compounds were found higher in fully irrigated plants as compared to water stress ones. Fertilizer treatments had no considerable effect on phenolic compounds. (author)

The pollution of water by nitrates of chemical fertilizers

International Nuclear Information System (INIS)

Halwani, Jalal

1998-01-01

The following article is a literature review that summarizes results from field studies devoted to chemical analysis of water in Lebanon. Agricultural practices and the use of fertilizers may affect surface waters, ground water and drinking water. Much attention has been given to their environmental consequences, especially those related to water pollution by Nitrates and human health. The Nitrate content should not exceed in drinking water more than 50 mg/l for adults and 25 mg/l for children and pregnant women. Studies suggest incorporation of quick remedial measures to combat pollution in marine environments

Phytoremediation of Alberta oil sand tailings using native plants and fungal endophytes

Science.gov (United States)

Repas, T.; Germida, J.; Kaminskyj, S.

2012-04-01

Fungal endophytes colonize host plants without causing disease. Some endophytes confer plant tolerance to harsh environments. One such endophyte, Trichoderma harzianum strain TSTh20-1, was isolated from a plant growing on Athabasca oil sand tailings. Tailing sands are a high volume waste product from oil sand extraction that the industry is required to remediate. Tailing sands are low in organic carbon and mineral nutrients, and are hydrophobic due to residual polyaromatic hydrocarbons. Typically, tailing sands are remediated by planting young trees in large quantities of mulch plus mineral fertilizer, which is costly and labour intensive. In greenhouse trials, TSTh20-1 supports growth of tomato seedlings on tailing sands without fertilizer. The potential use of TSTh20-1 in combination with native grasses and forbs to remediate under field conditions is being assessed. Twenty-three commercially available plant species are being screened for seed germination and growth on tailing sands in the presence of TSTh20-1. The best candidates from this group will be used in greenhouse and small scale field trials. Potential mechanisms that contribute to endophyte-induced plant growth promotion, such as plant hormone production, stress tolerance, mineral solubilization, and uptake are also being assessed. As well, TSTh20-1 appears to be remarkably frugal in its nutrient requirements and the possibility that this attribute is characteristic of other plant-fungal endophytes from harsh environments is under study.

Soil water erosion under different cultivation systems and different fertilization rates and forms over 10 years

Directory of Open Access Journals (Sweden)

Ildegardis Bertol

2014-12-01

Full Text Available The action of rain and surface runoff together are the active agents of water erosion, and further influences are the soil type, terrain, soil cover, soil management, and conservation practices. Soil water erosion is low in the no-tillage management system, being influenced by the amount and form of lime and fertilizer application to the soil, among other factors. The aim was to evaluate the effect of the form of liming, the quantity and management of fertilizer application on the soil and water losses by erosion under natural rainfall. The study was carried out between 2003 and 2013 on a Humic Dystrupept soil, with the following treatments: T1 - cultivation with liming and corrective fertilizer incorporated into the soil in the first year, and with 100 % annual maintenance fertilization of P and K; T2 - surface liming and corrective fertilization distributed over five years, and with 75 % annual maintenance fertilization of P and K; T3 - surface liming and corrective fertilization distributed over three years, and with 50 % annual maintenance fertilization of P and K; T4 - surface liming and corrective fertilization distributed over two years, and with 25 % annual maintenance fertilization of P and K; T5 - fallow soil, without liming or fertilization. In the rotation the crops black oat (Avena strigosa , soybean (Glycine max , common vetch (Vicia sativa , maize (Zea mays , fodder radish (Raphanus sativus , and black beans (Phaseolus vulgaris . The split application of lime and mineral fertilizer to the soil surface in a no-tillage system over three and five years, results in better control of soil losses than when split in two years. The increase in the amount of fertilizer applied to the soil surface under no-tillage cultivation increases phytomass production and reduces soil loss by water erosion. Water losses in treatments under no-tillage cultivation were low in all crop cycles, with a similar behavior as soil losses.

The effects of production water, WAF or CEWAF on the fertilization success of Atlantic cod eggs

International Nuclear Information System (INIS)

Burridge, L; Wong, D.; Trippel, E.

2010-01-01

Production water (PW), dispersed oil, and oil released from offshore oil and gas platforms can adversely affect fish populations. In this study, eggs from Atlantic cod were fertilized in the presence of PW collected from the Terra Nova and Hibernia offshore platforms in 2008. Cod eggs were also fertilized in the presence of the water accommodated fraction (WAF) and chemically enhanced water accommodated fraction (CEWAF) of Alaskan North Slope oil (ANS). Results of the study showed that exposure to the Terra Nova PW at 12 per cent (V/V) or higher resulted in significantly lower fertilization rates than those observed in controls. Exposure to Hibernia PW at 0.5 per cent (V/V) also resulted in significantly lower fertilization rates. The WAF of ANS up to 25 per cent (V/V) had no effect on fertilization rates. At 50 per cent (V/V), the fertilization rate for WAF ANS was much lower than rates observed in controls. The CEWAF significantly reduced fertilization at all tested concentrations.

Submarine sand ridges and sand waves in the eastern part of the China Sea

Science.gov (United States)

Wu, Ziyin; Li, Shoujun; Shang, Jihong; Zhou, Jieqiong; Zhao, Dineng; Liang, Yuyang

2016-04-01

Integrated with multi-beam and single-beam echo sounding data, as well as historical bathymetric data, submarine bathymetric maps of the eastern part of the China Sea, including the Bohai Sea, Huanghai Sea, and East China Sea, are constructed to systematically study submarine sand ridges and sand waves in the eastern part of the China Sea, combined with high-resolution seismic, sub-bottom profile and borehole data. Submarine sand ridges are extraordinarily developed in the eastern part of the China Sea, and 7 sand ridge areas can be divided from north to south, that is, the Laotieshan Channel sand ridge area in the Bohai Sea, the Korea Bay sand ridge area in the southern Huanghai Sea, the sand ridge area in the eastern Huanghai islands and the Huanghai Troughs, the Jianggang sand ridge area in the western Huanghai Sea, the sand ridge area in the East China Sea shelf, and the sand ridge and sand wave area in the Taiwan Strait and Taiwan Banks. The distribution area of the sand ridges and sand waves covers more than 450,000 km2, wherein ~10,000 km2 in the Bohai Bay, ~200,000 km2 in the Huanghai Sea, ~200,000 km2 in the East China Sea shelf, and ~40,000 km2 in the Taiwan Strait and Taiwan Banks, respectively. The great mass of sand ridges are distributed within water depth of 5-160 m, with a total length of over 160 km and a main width of 5-10 km. The inner structure of the sand ridges presents features of high-angle inclined beddings, with main lithology of sands, sand-mud alternations partly visible, and a small number of mud cores. Dating results indicate that the sand ridges in the eastern part of the China Sea are mainly developed in the Holocene. Sea-level variation dominates the sand ridge evolution in the eastern part of the China Sea since the LGM, and the sand ridges developed in the area of < 60m water depth are appeared in bad activity, meanwhile sand ridges with good activity are still developed in large scale.

Effects of re-application of nitrogen fertilizer on forest soil-water chemistry, with special reference to cadmium

International Nuclear Information System (INIS)

Hoegbom, Lars; Nohrstedt, Hans-Oerjan

2000-09-01

A greatly increased concentration of cadmium was found in soil water following the application of nitrogen fertilizer. Our study was conducted at an experimental site in the western part of central Sweden. Prior to this, the area had been used to study the effects of the repeated application of fertilizer, under different regimes, on forest production. In this experiment, we examined the residual effects of previous nitrogen fertilizer application regimes on soil-water chemistry, following a final, additional fertilizer application. Soil water was sampled using suction lysimeters installed at a depth of 50 cm. However, due to the failure of the lysimeters at two of the study plots, the differences between fertilizer regimes could not be evaluated. Instead, we focused on changes in the solubility of cadmium and aluminium caused by soil-water acidification due to the re-application of nitrogen fertilizer. Every fourth or eighth year, between 1981 and 1997, the study plots received 150 kg N ha -1 , in the form of ammonium nitrate (AN) and calcium ammonium nitrate (CAN). The effects of the final fertilizer application (CAN) were studied. Application of nitrogen fertilizer resulted in a rapid increase in NO 3 - concentration in soil-water, and a decrease in pH. The increased soil-water acidity resulted in some metals becoming more soluble and occurring in higher concentrations within the soil water. The increase in concentration of some toxic heavy metals, such as cadmium, was of concern. The highest measured cadmium concentration was 2.7 μg l -1 , compared to the government health limit of 5 μg l -1 for drinking water. The cadmium detected must originate from the soil since it was not present in the nitrogen fertilizer. Cadmium is highly toxic to both animals and plants, and knowledge of its occurrence, in relation to various silvicultural operations, is of great importance

Evaluate of head loss, sediment value and copper removal in sand media (rapid sand filter

Directory of Open Access Journals (Sweden)

Daneshi Navab

2014-06-01

Full Text Available Along with the technology development and increasing consumption of water resources, we are experiencing low qualities in the mentioned resources. Copper brings about serious environment al pollution, threatening human health and ecosystem. This metal found variously in water resources and industrial activities. Therefore, it needs to treat the water resources from these excessive amounts. Different methods have used for this reason but the most used method during recent years has been the absorption by economic absorbers such as sand. Rapid sand filters usually used in water and wastewater treatment plants for water clarification. In this research, a single layer gravity rapid sand filter has used to reduce different concentrations of copper. sediment value and head loss arising in filter media is simulated by using combination of Carman-Kozeny, Rose and Gregory models in different discharges of rapid sand filter. Results have shown that with increasing in discharge and decreasing in input copper concentration, arriving time to given head loss, is increasing. In addition, results demonstrated that with increasing in copper concentration in influent, removal efficiency is decreasing somewhat. Results of this research can applied in an appropriate design of rapid sand filter to copper removal, a prediction of rapid sand filter ability to copper removal and an estimation of arising head loss during filter work thus evaluating of time interval backwash. DOI: http://dx.doi.org/10.3126/ije.v3i2.10641 International Journal of the Environment Vol.3(2 2014: 276-286

Impacts of Nitrogen Fertilization on Carbon and Water Balances in Different-aged Westcoast Douglas-fir Stands

Science.gov (United States)

Jassal, P.; Black, A.; Bruemmer, C.; Nesic, Z.; Spittlehouse, D.; Trofymow, T.

2009-05-01

Using the eddy-covariance technique, we have been measuring, since 1998, CO2, water vapour and energy exchange between the atmosphere and the ecosystem in three different-aged Westcoast Douglas-fir (Pseudotsuga menziesii) stands (9, 21 and 60 year-old in 2009, hereafter known as HDF00, HDF88 and DF49, respectively). These stands were fertilized with urea in January 2007. While HDF88 and DF49 were fertilized aerially with 200 kg N ha-1, HDF00, due to its young age and competing brush, was fertilized manually at 60 kg N ha-1. This paper reports the environmental controls of pre-fertilization interannual variability in ecosystem respiration (R), gross photosynthesis (P) and evapotranspiration (E), and discusses the effects of N- fertilization on these fluxes and net ecosystem productivity (NEP = P - R, i.e., carbon sequestration) and water use efficiency (WUE = P/E). For DF49, both pre-fertilization annual P and R responded positively to increases in mean annual air temperature and soil water content, but R was more responsive to both these environmental variables. Using these relationships, we calculated P and R for 2007 and 2008 assuming the stand was not fertilized. A comparison with measured 2007 and 2008 fluxes indicated that fertilization increased P and had almost no effect on R and soil respiration with the consequence that NEP was increased by 170 and 90 g C m- 2 during 2007 and 2008, respectively. Pre-fertilization annual E was modelled as a function of mean annual temperature, annual total photosynthetically active radiation, and precipitation for the previous year. Using this model to calculate 2007 and 2008 values of E for the unfertilized stand and comparing these with measured values in the fertilized stand indicated that fertilization had no effect on E, neither in 2007 nor in 2008. As a result, annual water use efficiency increased from a mean of 4.9 g C (kg water)-1 for 1998-2006 to 5.2 g C (kg water)-1 in 2007 and 2008. A similar analysis was

Effects of oil sands waste water on the wood frog (rana sylvatica)

Energy Technology Data Exchange (ETDEWEB)

Hersikorn, B.; Smits, J.E. [Saskatchewan Univ., Regina, SK (Canada)

2007-07-01

The sustainability of various reclamation strategies can be determined by the growth and health of indigenous amphibians (Wood Frogs). This paper referred to the large quantities of tailings water that are generated by oil sand extraction activities. It presented the results of a study that was conducted in the spring and summer of 2006 and 2007 on reclaimed formation wetlands comprising tailings water. The objective was to understand the impact of these wetlands on native amphibians. Frogs were exposed to wetlands containing oil sands process affected water (OSPW) and reference water (no OSPW). Six experimental trenches were made at one site in the first year. Each trench had 3 enclosures with 50 tadpoles. In the second year, there were 13 sites, including 6 reference and 7 OSPW affected sites, which were classified as old (more than 8 yrs) or young (less than 7 yrs). Four enclosures, with 50 tadpoles each, were placed in each wetland. The study involved the evaluation of growth rate, survival, time to metamorphosis, thyroid hormone concentrations, liver EROD activity, and tissue retinol concentrations. In addition, stable isotopes were used to track carbon flow from primary production plants, through the food chain, to tadpoles and frogs which represent intermediate and higher trophic levels in reclaimed wetlands.

Isotope and radiation techniques for efficient water and fertilizer use in semi-arid regions

International Nuclear Information System (INIS)

1986-04-01

The Joint FAO/IAEA Division carried out a coordinated research programme, which was concerned with the efficiency of water and fertilizer uses in semi-arid farming systems. The present publication is a summary of the individual contributions from Belgium, Chile, Ivory Coast, Cyprus, France, India, Israel, Romania, Senegal, Sri Lanka and the United States of America, over the period 1978-1984. Water and fertilizer uptake by crops are dynamic processes affected by several factors of the soil-plant-atmosphere system. The neutron moisture meters were used not only to measure soil water contents but also to understand water dynamics under field conditions. Nitrogen is the most limiting nutrient in many semi-arid regions, and as its absorption is very much related to water dynamics in the soil, experiments using N-15 labelled fertilizer were carried out, which are presented in this report

Development Of Silica Potassium Fertilizers From Trass Rock With Calcination Process

Science.gov (United States)

Wahyusi, KN; Siswanto

2018-01-01

Rocks and sand mines have important benefits for life. With the many benefits of rocks, it is a pity if Indonesia has a lot of raw material reserves waste it. Examples of the benefits of rocks that can be converted into silica potassium fertilizer by reacting with potassium hydroxide. Examples of rocks that can be taken trass rock. The procedure for making silica potassium is by reacting 100 mesh trass rock with KOH and K2CO3 reagents whose composition is arranged by weight ratio, where the base of the trass rock is 100 gr. The process is carried out at a temperature of 1.250 °C with a reaction time of 1 hour. The results obtained are the best silica potassium fertilizer for K2CO3 reagent which is 500gr: 74gr with SiO2 content: 26.8% and K2O content: 27.3%, with water solubility 24.02%, while for silica potassium fertilizer product from The best trass rock for KOH reagent is with a mol ratio of 400 gr : 60 gr with SiO2 content : 23.6% and K2O content: 22.2%, with 25.65% water solubility. The pore size of silica potassium fertilizer product of this trass rock, the range 350 - 1000 nm.

Gill histopathology of goldfish exposed to oil sands processed-waters

International Nuclear Information System (INIS)

Nero, V.; Farwell, A.J.; Dixon, D.G.; Lee, L.E.J.

2002-01-01

Large volumes of processed wastewater are generated through the oil extraction process at Alberta's Athabasca oil sand deposit. These wastewaters are very toxic to aquatic biota because they are high in salinity and consist of napthenic acids and polycyclic aromatic hydrocarbons (PAH). In this study, goldfish were caged in 3 different experimental ponds in order to evaluate the biological effects of aquatic reclamation alternatives for process-affected waters. The first pond was a control pond, while the other 2 ponds consisted of known and varying chemicals. The fish were exposed to the ponds for 19 days. Those in the pond with elevated levels of napthenic acids and high salinity exhibited severe gill histopathological changes. Alterations included epithelial hyperplasia resulting in severe lamellar fusion, chloride cell hyperplasia, and lamellar edema, all of which were believed to be defense responses of the fish. Additional severe gill alterations were also observed that may indicate the direct negative effects of oil sands processed-water on fish. Exposed goldfish also showed signs of necrosis and degenerative changes resulting in desquamation of the epithelial surfaces of the gill, which are symptoms seen in free-range exposure of yellow perch, a native fish species, at the same sites and exposure times

Gill histopathology of goldfish exposed to oil sands processed-waters

Energy Technology Data Exchange (ETDEWEB)

Nero, V.; Farwell, A.J.; Dixon, D.G. [Waterloo Univ., ON (Canada). Dept. of Biology; Lister, A.; Van Der Kraak, G.J. [Guelph Univ., ON (Canada); Lee, L.E.J. [Wilfred Laurier Univ., Waterloo, ON (Canada). Dept. of Biology

2002-07-01

Large volumes of processed wastewater are generated through the oil extraction process at Alberta's Athabasca oil sand deposit. These wastewaters are very toxic to aquatic biota because they are high in salinity and consist of napthenic acids and polycyclic aromatic hydrocarbons (PAH). In this study, goldfish were caged in 3 different experimental ponds in order to evaluate the biological effects of aquatic reclamation alternatives for process-affected waters. The first pond was a control pond, while the other 2 ponds consisted of known and varying chemicals. The fish were exposed to the ponds for 19 days. Those in the pond with elevated levels of napthenic acids and high salinity exhibited severe gill histopathological changes. Alterations included epithelial hyperplasia resulting in severe lamellar fusion, chloride cell hyperplasia, and lamellar edema, all of which were believed to be defense responses of the fish. Additional severe gill alterations were also observed that may indicate the direct negative effects of oil sands processed-water on fish. Exposed goldfish also showed signs of necrosis and degenerative changes resulting in desquamation of the epithelial surfaces of the gill, which are symptoms seen in free-range exposure of yellow perch, a native fish species, at the same sites and exposure times.

[Effects of water deficit and nitrogen fertilization on winter wheat growth and nitrogen uptake].

Science.gov (United States)

Qi, You-Ling; Zhang, Fu-Cang; Li, Kai-Feng

2009-10-01

Winter wheat plants were cultured in vitro tubes to study their growth and nitrogen uptake under effects of water deficit at different growth stages and nitrogen fertilization. Water deficit at any growth stages could obviously affect the plant height, leaf area, dry matter accumulation, and nitrogen uptake. Jointing stage was the most sensitive stage of winter wheat growth to water deficit, followed by flowering stage, grain-filling stage, and seedling stages. Rewatering after the water deficit at seedling stage had a significant compensation effect on winter wheat growth, and definite compensation effect was observed on the biomass accumulation and nitrogen absorption when rewatering was made after the water deficit at flowering stage. Under the same nitrogen fertilization levels, the nitrogen accumulation in root with water deficit at seedling, jointing, flowering, and grain-filling stages was reduced by 25.82%, 55.68%, 46.14%, and 16.34%, and the nitrogen accumulation in aboveground part was reduced by 33.37%, 51.71%, 27.01%, and 2.60%, respectively, compared with no water deficit. Under the same water deficit stages, the nitrogen content and accumulation of winter wheat decreased with decreasing nitrogen fertilization level, i. e., 0.3 g N x kg(-1) FM > 0.2 g N x kg(-1) FM > 0.1 g N x kg(-1) FM. Nitrogen fertilization had obvious regulation effect on winter wheat plant growth, dry matter accumulation, and nitrogen uptake under water stress.

Coating with fungicide and different doses of fertilizer in vinhatico ...

African Journals Online (AJOL)

Thus, the aim of this study was to evaluate and identify the physical and physiological quality of mahogany seeds that are coated with fertilizer and fungicide. The treatments were: seed coating with sand + lime + fungicide with different doses of fertilizers. The seeds were evaluated in the laboratory and in a greenhouse.

Part of the green plan : suppliers are helping the coal and oil sands industries to address environmental concerns

Energy Technology Data Exchange (ETDEWEB)

Sabourin, M.

2009-09-15

The Canadian coal and oil sands industries operate in one of the most stringent environmental regulatory frameworks found in the world. The purpose of the strict regulations is to ensure that Canadian energy resources are developed safely, responsibly and efficiently. Their primary objectives involve the protection of water supplies and aquatic life. This article discussed how suppliers are helping the coal and oil sands industries address environmental concerns. Several examples were provided. In terms of water protection and management, EBA Engineering Consultants has helped mining companies comply with strict environmental regulations and has assisted them in obtaining the necessary permits and establishing monitoring programs. In terms of containment, the Layfield Group's silt and sediment control products has helped prevent fine soil particles from running off into and clouding local water courses. In terms of land reclamation and remediation, IW Kuhn Environmental Ltd., has provided soil remediation services, including re-vegetation using hydroseeding which involves the sowing of seeds with a hosed jet of water. This article also discussed the many green technology products that have been developed and commercialized by EarthRenew for application in coal and oil sands projects. Their patented waste renew facilities can process and cook manures, biosolids or green wastes into organic fertilizers that could be used in land repair applications. 5 figs.

Efficient Use of Organic Sources by Sorghum Plants Grown on Sand Soil Using "1"5N Stable Isotope Technique

International Nuclear Information System (INIS)

EL Hassanin, A.S; Khalifa, A.M; Abdel Aziz, H.A; Galal, Y.G.M; Abdel Salam, M.F

2015-01-01

A green house experiment was conducted at Soil and Water Research Department, Nuclear Research Center, Atomic Energy Authority, Inshas, Egypt. Different organic/bio fertilizer and mineral fertilizers were existed for detection and evaluation of sorghum crop response when grown on sand soils. Mineral fertilizer in the form of labeled ammonium sulfate with 2% "1"5N atom excess was applied at two rates of 200 and 400 mg N pot-1 and unfertilized control treatment also included. Different organic fertilizers such as compost, chicken manure and leucaena residues were applied at the same rates per pot according to its content of nitrogen. Sorghum plants treated with organic or mineral fertilizers were inoculated with Azotobacter chrooccocum as a representative of associative nitrogen fixing microorganisms. Un inoculated plants were also included. Completely randomized block design was followed for statistical analysis. Nitrogen use efficiency (%NUE) was estimated using the portion of N derived from mineral fertilizer. Experimental data released from this work could be summarized as following: Dry matter yield of stalks and roots were increased with increasing mineral fertilizer rates where the best increments detected at 100% N rate as compared to the unfertilized control

Performance comparison of sand and fine sawdust vermifilters in treating concentrated grey water for urban poor.

Science.gov (United States)

Adugna, Amare T; Andrianisa, Harinaivo A; Konate, Yacouba; Ndiaye, Awa; Maiga, Amadou H

2015-01-01

A comparative investigation was conducted for 10 months with sand and fine sawdust vermifilters and a control unit to treat concentrated grey water generated from a poor urban household in Ouagadougou, Burkina Faso. Each of the filters was made up of cylindrical DN200-PVC pipes and filled with 10 cm of gravel at the bottom. On top of the gravel layer, filter 1 (fully sand, F1) was completed with 40 cm of sand and 10 cm of fine sawdust, filter 2 (partially sand, F2) with 20 cm of sand and 30 cm of fine sawdust, respectively, and filter 3 (fully sawdust, F3) and 4 (control, F4) with 50 cm of fine sawdust only. Two hundred Eudrilus eugeniae earthworms were inoculated in each of the vermifilters. The vermifiltration system was supplied with grey water four times per day at a hydraulic loading rate of 64 L/m(2)/day on a batch basis. The removal efficiencies of biological oxygen demand, total chemical oxygen demand, and dissolved chemical oxygen demand (dCOD) by the vermifilters were 25-30% higher than the control, but little differences were observed in terms of total suspended solids and coliform removal efficiencies. Though there was no significant difference in the performance of the three vermifilters (p > 0.05), except for dCOD removal efficiency, the lifespan of F2 and F3 was longer than that of F1. Therefore, fine sawdust can substitute sand as a filter medium in vermifilters.

Development of a bioassay using walleye (Sander vitreus) to assess the toxicity of oil sands sediments

Energy Technology Data Exchange (ETDEWEB)

Turcotte, D.; Yuan, H.; Tumber, V.; Parrott, J. [Environment Canada, Ottawa, ON (Canada); Raine, J. [Saskatchewan Univ., Saskatoon, SK (Canada)

2010-07-01

This study examined the effects of sediments from the Athabasca oil sands area on fish development and survival. Walleye (Sander vitreus) which inhabit the Athabasca River are exposed to natural sources of bitumen eroding from the McMurray formation. This study described the design and implementation of a daily-renewal bioassay to evaluate the potential effects of toxicants on walleye development. Eggs were collected and fertilized with milt from spawning wild walleye captured from Lake Diefenbaker in Saskatchewan. The fertilized eggs were exposed to different concentrations of sediments or culture water only (negative controls) until complete yolk absorption of control fish. The walleye embryos were fed brine shrimp daily after hatching and the developing fish were examined for morphological deformities, survival, hatching success, and changes in weight and length between treatments. Organics concentrations in fish tissues and water were measured when possible. Fathead minnows and northern pikes will also be exposed to the same sediments in order to compare the relative sensitivity of the three species.

Drawer compacted sand filter: a new and innovative method for on-site grey water treatment.

Science.gov (United States)

Assayed, Almoayied; Chenoweth, Jonathan; Pedley, Steven

2014-01-01

In this paper, results ofa new sand filter design were presented. The drawer compacted sand filter (DCSF) is a modified design for a sand filter in which the sand layer is broken down into several layers, each of which is 10 cm high and placed in a movable drawer separated by a 10 cm space. A lab-scale DCSF was designed and operated for 330 days fed by synthetic grey water. The response of drawer sand filters to variable hydraulic and organic loading rates (HLR and OLR) in terms of biological oxygen demand (BODs), chemical oxygen demand (COD), total suspended solids (TSS), pH, electrical conductivity and Escherichia coli reductions were evaluated. The HLR was studied by increasing from 72 to 142 L m(-2) day(-1) and OLR was studied by increasing it from 23 to 30 g BOD5 m(-2) day(-1) while keeping the HLR constant at 142 L m(-2) day(-1). Each loading regime was applied for 110 days. Results showed that DCSF was able to remove >90% of organic matter and total suspended solids for all doses. No significant difference was noticed in terms of overall filter efficiency between different loads for all parameters. Significant reduction in BOD5 and COD (P water was drained through the third drawer in all tested loads. The paper concludes that DCSF would be appropriate for use in dense urban areas as its footprint is small and is appropriate for a wide range of users because of its convenience and low maintenance requirements.

Study on Water Distribution Imaging in the Sand Using Propagation Velocity of Sound with Scanning Laser Doppler Vibrometer

Science.gov (United States)

Sugimoto, Tsuneyoshi; Nakagawa, Yutaka; Shirakawa, Takashi; Sano, Motoaki; Ohaba, Motoyoshi; Shibusawa, Sakae

2013-07-01

We propose a method for the monitoring and imaging of the water distribution in the rooting zone of plants using sound vibration. In this study, the water distribution measurement in the horizontal and vertical directions in the soil layer was examined to confirm whether a temporal change in the volume water content of the soil could be estimated from a temporal changes in propagation velocity. A scanning laser Doppler vibrometer (SLDV) is used for measurement of the vibration velocity of the soil surface, because the highly precise vibration velocity measurement of several many points can be carried out automatically. Sand with a uniform particle size distribution is used for the soil, as it has high plasticity; that is, the sand can return to a dry state easily even if it is soaked with water. A giant magnetostriction vibrator or a flat speaker is used as a sound source. Also, a soil moisture sensor, which measures the water content of the soil using the electric permittivity, is installed in the sand. From the experimental results of the vibration measurement and soil moisture sensors, we can confirm that the temporal changes of the water distribution in sand using the negative pressure irrigation system in both the horizontal and vertical directions can be estimated using the propagation velocity of sound. Therefore, in the future, we plan to develop an insertion-type sound source and receiver using the acceleration sensors, and we intend to examine whether our method can be applied even in commercial soil with growing plants.

Study on of Seepage Flow Velocity in Sand Layer Profile as Affected by Water Depth and Slope Gradience

Science.gov (United States)

Han, Z.; Chen, X.

2017-12-01

BACKGROUND: The subsurface water flow velocity is of great significance in understanding the hydrodynamic characteristics of soil seepage and the influence of interaction between seepage flow and surface runoff on the soil erosion and sediment transport process. OBJECTIVE: To propose a visualized method and equipment for determining the seepage flow velocity and measuring the actual flow velocity and Darcy velocity as well as the relationship between them.METHOD: A transparent organic glass tank is used as the test soil tank, the white river sand is used as the seepage test material and the fluorescent dye is used as the indicator for tracing water flow, so as to determine the thickness and velocity of water flow in a visualized way. Water is supplied at the same flow rate (0.84 L h-1) to the three parts with an interval of 1m at the bottom of the soil tank and the pore water velocity and the thickness of each water layer are determined under four gradient conditions. The Darcy velocity of each layer is calculated according to the water supply flow and the discharge section area. The effective discharge flow pore is estimated according to the moisture content and porosity and then the relationship between Darcy velocity and the measured velocity is calculated based on the water supply flow and the water layer thickness, and finally the correctness of the calculation results is verified. RESULTS: According to the velocity calculation results, Darcy velocity increases significantly with the increase of gradient; in the sand layer profile, the flow velocity of pore water at different depths increases with the increase of gradient; under the condition of the same gradient, the lower sand layer has the maximum flow velocity of pore water. The air-filled porosity of sand layer determines the proportional relationship between Darcy velocity and pore flow velocity. CONCLUSIONS: The actual flow velocity and Darcy velocity can be measured by a visualized method and the

Importance of copper for nitrification in biological rapid sand filters for drinking water production

DEFF Research Database (Denmark)

Wagner, Florian Benedikt

When anoxic groundwater is treated to produce drinking water, ammonium is commonly removed through nitrification in rapid sand filters. Nitrification is a biological process, and is mediated by chemoautotrophic microorganisms. Ammonia oxidizing bacteria (AOB) and archaea (AOA) oxidize ammonium...... to remove ammonium to below the national drinking water quality standard of 0.05 mg NH4+/L. A better process understanding of nitrifying biofilters is needed to optimize treatment performance, remediate existing filters, and to prevent future nitrification problems. The frequent incidents of insufficient...... in the oxidation of ammonia to hydroxylamine. Thus, slow and incomplete nitrification could be caused by a lack of sufficient amounts of copper. The overall aim of this PhD project was therefore to determine whether copper supplementation could enhance nitrification in rapid sand filters with incomplete...

Soybean response to nitrogen fertilizer under water deficit conditions

African Journals Online (AJOL)

user

2011-04-18

Apr 18, 2011 ... In order to determine the effect of water deficit and nitrogen fertilizer application on growth indices, yield and yield ... located in 39°N and 47°E longitude and has 32 m altitude. The soil ...... Stable Isotope Research (GASIR).

Pattern formation - Instabilities in sand ripples

DEFF Research Database (Denmark)

Hansen, J. L.; v. Hecke, M.; Haaning, A.

2001-01-01

Sand ripples are seen below shallow wavy water and are formed whenever water oscillates over a bed of sand. Here we analyse the instabilities that can upset this perfect patterning when the ripples are subjected to large changes in driving amplitude or frequency, causing them to deform both...

Fertilizers mobilization in alluvial aquifer: laboratory experiments

Science.gov (United States)

Mastrocicco, M.; Colombani, N.; Palpacelli, S.

2009-02-01

In alluvial plains, intensive farming with conspicuous use of agrochemicals, can cause land pollution and groundwater contamination. In central Po River plain, paleo-channels are important links between arable lands and the underlaying aquifer, since the latter is often confined by clay sediments that act as a barrier against contaminants migration. Therefore, paleo-channels are recharge zones of particular interest that have to be protected from pollution as they are commonly used for water supply. This paper focuses on fertilizer mobilization next to a sand pit excavated in a paleo-channel near Ferrara (Italy). The problem is approached via batch test leaking and columns elution of alluvial sediments. Results from batch experiments showed fast increase in all major cations and anions, suggesting equilibrium control of dissolution reactions, limited availability of solid phases and geochemical homogeneity of samples. In column experiments, early elution and tailing of all ions breakthrough was recorded due to preferential flow paths. For sediments investigated in this study, dispersion, dilution and chemical reactions can reduce fertilizers at concentration below drinking standards in a reasonable time frame, provided fertilizer loading is halted or, at least, reduced. Thus, the definition of a corridor along paleo-channels is recommended to preserve groundwater quality.

Phosphorus availability from phosphate rock and sewage sludge as influenced by the addition of water soluble phosphate fertilizer

International Nuclear Information System (INIS)

Zapata, F.; Zaharah, A.R.

2002-01-01

Phosphorus (P) inputs are required for sustainable agricultural production in most acid soils of the tropics and subtropics. Phosphate rocks (PR) and organic materials have been suggested as alternative P sources in these soils. Quantitative information on the P availability from sewage sludge (SL) is scanty. Methods to improve the effectiveness of PR such as partial acidulation and compaction with water-soluble P sources have been recommended. The objective of this greenhouse study was to evaluate the relative agronomic effectiveness (RAE) of Florida PR and sewage sludges (irradiated and non-irradiated) applied alone and in mixture with a water-soluble source (triple superphosphate, TSP) at two rates (50 and 150 mg P kg -1 soil). The 32 P isotope dilution technique was utilised to determine the proportion of P in the plant taken up from the P fertilizer treatments. Wheat was grown on an acid loamy sand Dystric Eutrocrepts and harvested 6 weeks after planting. Results on total P uptake and the RAE of the P fertilizer sources tested indicated that the addition of 50 mg P kg -1 soil as TSP was adequate in supplying P to the 6-week-old wheat plants as compared to PR and sewage sludge. Intermediate values were obtained for the mixtures. Similar responses were observed for the high P rate. For a given P rate, phosphorus uptake from PR and SL in presence of TSP was higher than P uptake from these sources alone, indicating an enhancement effect of TSP on the effectiveness of these non-readily available sources. With respect to P uptake from PR applied alone, the relative increases in P uptake from PR due to TSP influence were 52 and 67% for the low and high P rates, respectively. The relative increases in P uptake from SL due to TSP when compared to P uptake from SL alone were 102 and 59% for the low and high P rates of application. Application of a water-soluble P fertilizer together with a non-readily available P source shows an enhancement on the P uptake from the non

Phosphorus availability from phosphate rock and sewage sludge as influenced by the addition of water soluble phosphate fertilizer

Energy Technology Data Exchange (ETDEWEB)

Zapata, F. [Soil and Water Management and Crop Nutrition Section, International Atomic Energy Agency, Vienna (Austria)]. E-mail: F.Zapata@iaea.org; Zaharah, A.R. [Department of Land Management, Universiti Putra Malaysia, Serdang, Selangor (Malaysia)

2002-05-15

Phosphorus (P) inputs are required for sustainable agricultural production in most acid soils of the tropics and subtropics. Phosphate rocks (PR) and organic materials have been suggested as alternative P sources in these soils. Quantitative information on the P availability from sewage sludge (SL) is scanty. Methods to improve the effectiveness of PR such as partial acidulation and compaction with water-soluble P sources have been recommended. The objective of this greenhouse study was to evaluate the relative agronomic effectiveness (RAE) of Florida PR and sewage sludges (irradiated and non-irradiated) applied alone and in mixture with a water-soluble source (triple superphosphate, TSP) at two rates (50 and 150 mg P kg{sup -1} soil). The {sup 32}P isotope dilution technique was utilised to determine the proportion of P in the plant taken up from the P fertilizer treatments. Wheat was grown on an acid loamy sand Dystric Eutrocrepts and harvested 6 weeks after planting. Results on total P uptake and the RAE of the P fertilizer sources tested indicated that the addition of 50 mg P kg{sup -1} soil as TSP was adequate in supplying P to the 6-week-old wheat plants as compared to PR and sewage sludge. Intermediate values were obtained for the mixtures. Similar responses were observed for the high P rate. For a given P rate, phosphorus uptake from PR and SL in presence of TSP was higher than P uptake from these sources alone, indicating an enhancement effect of TSP on the effectiveness of these non-readily available sources. With respect to P uptake from PR applied alone, the relative increases in P uptake from PR due to TSP influence were 52 and 67% for the low and high P rates, respectively. The relative increases in P uptake from SL due to TSP when compared to P uptake from SL alone were 102 and 59% for the low and high P rates of application. Application of a water-soluble P fertilizer together with a non-readily available P source shows an enhancement on the P

Impacts of sand and dust storms on agriculture and potential agricultural applications of a SDSWS

International Nuclear Information System (INIS)

Stefanski, R; Sivakumar, M V K

2009-01-01

This paper will give an overview of the various impacts of sand and dust storms on agriculture and then address the potential applications of a Sand and Dust Storm Warning System (SDSWS) for agricultural users. Sand and dust storms have many negative impacts on the agricultural sector including: reducing crop yields by burial of seedlings under sand deposits, the loss of plant tissue and reduced photosynthetic activity as a result of sandblasting, delaying plant development, increasing end-of-season drought risk, causing injury and reduced productivity of livestock, increasing soil erosion and accelerating the process of land degradation and desertification, filling up irrigation canals with sediments, covering transportation routes, affecting water quality of rivers and streams, and affecting air quality. One positive impact is the fertilization of soil minerals to terrestrial ecosystems. There are several potential agricultural applications of a SDSWS. The first is to alert agricultural communities farmers to take preventive action in the near-term such as harvesting maturing crops (vegetables, grain), sheltering livestock, and strengthening infrastructure (houses, roads, grain storage) for the storm. Also, the products of a SDSWS could be used in for monitoring potential locust movement and post-storm crop damage assessments. An archive of SDSWS products (movement, amount of sand and dust) could be used in researching plant and animal pathogen movement and the relationship of sand and dust storms to disease outbreaks and in developing improved soil erosion and land degradation models.

Effects of solar collecting area and water flow rate on the performance of a sand bed solar collector

International Nuclear Information System (INIS)

Maganhar, A.L.; Memon, A.H.; Panhwar, M.I.

2005-01-01

The often discussed renewable sources of energy have been great interest to energy researchers and planners for quite some time. The primary of renewing all sources of energy is the sun. There have been two main problems not yet fully resolved. One is the large scale production of energy and other is the cost factor. In the present study, the cost factor is under consideration. In this regard a non-conventional solar collector using indigenous material (pit sand) as solar absorber is designed and manufactured. This paper presents the results of an investigation of the effect of solar collecting area and water flow rate on the performance of a pit sand bed solar collector especially in terms of rise in water temperature. Three pit sand solar collectors of area 1m/sup 2/ each were connected in series to enhance the collecting area and the system was tested for different flow rates. Experimental results proved that there was increase in water temperature with increase in solar collecting area an decreases in water temperature with increase in flow rate. (author)

Production of high quality water for oil sands application

Energy Technology Data Exchange (ETDEWEB)

Beaudette-Hodsman, C.; Macleod, B. [Pall Corp., Mississauga, ON (Canada); Venkatadri, R. [Pall Corp., East Hills, NY (United States)

2008-10-15

This paper described a pressurized microfiltration membrane system installed at an oil sands extraction site in Alberta. The system was designed to complement a reverse osmosis (RO) system installed at the site to produce the high quality feed water required by the system's boilers. Groundwater in the region exhibited moderate total suspended solids and high alkalinity and hardness levels, and the RO system required feed water with a silt density index of 3 or less. The conventional pretreatment system used at the site was slowing down production due to the severe fouling of the RO membranes. The new microfiltration system contained an automated PVDF hollow fiber microfiltration membrane system contained in a trailer. Suspended particles and bacteria were captured within the filter, and permeate was sent to the RO unit. Within 6 hours of being installed, the unit was producing water with SDI values in the range of 1.0 to 2.5. It was concluded that the microfiltration system performed reliably regardless of wide variations in feed water quality and flow rates. 3 refs., 1 tab., 8 figs.

Continued studies of soil improvement and revegetation of tailings sand slopes. Environmental Research Monograph 1977-4

Energy Technology Data Exchange (ETDEWEB)

Rowell, M J

1977-01-01

Fertilizer studies continued on a 5-year old revegetated area on a tailings sand dike in the Athabasca Tar Sands area. In June 1976 levels of available N, P, K, and S were adequate for plant growth. However, even where fertilizers were added levels of mineral N had dropped to low levels by September. Plant top production early in the 1976 season was increased by application of nitrogen fertilizer during the previous August. Erosion of the area was negligible in 1976. In the new revegetation experiments on steep tailings and slopes, erosion could be minimized by the rapid establishment of a plant cover. Nutrient losses in surface water runoff amounted to a maximum of only 2.6 kg N, 0.4 kg P, 4.1 kg K and 3.4 kg S/ha in the treatments studied. Water infiltration into the dike was rapid and varied between 24.0 and 30.5 cm/h. Estimates suggested that between 13 and 34% of the intercepted rainfall leached below the 30 cm depth while plants were being established during the first year of growth. Estimates of nutrient losses below the root zone (30 cm) ranged between 1.3 and 31.2 kg N/ha; <0.1 kg P/ha; 1.1 and 10.1 kg K/ha and 4.8 to 38.1 kg S/ha in the different treatments studied. The seed mix used contained oats as a nurse crop and 9 grass and 4 legume species. Plant growth was adequate to protect the soil surface from serious erosion. The dry weight production by the oats was considerably greater than for either the grasses or legumes. The cover produced by grasses and legumes alone would have been adequate in terms of erosion control except in those treatments involving heavy applications of mine overburdens. The dry weight production of root and shoot tissues was about the same. Root growth was largely restricted to the surface 15 cm. Total numbers of bacteria, fungi and actinomycetes as well as total soil respiration was considerably greater in soils from the revegetation experiments in comparison to samples of fresh or weathered tailings sand.

Integrated metagenomic and physiochemical analyses to evaluate the potential role of microbes in the sand filter of a drinking water treatment system.

Directory of Open Access Journals (Sweden)

Yaohui Bai

Full Text Available While sand filters are widely used to treat drinking water, the role of sand filter associated microorganisms in water purification has not been extensively studied. In the current investigation, we integrated molecular (based on metagenomic and physicochemical analyses to elucidate microbial community composition and function in a common sand filter used to treat groundwater for potable consumption. The results revealed that the biofilm developed rapidly within 2 days (reaching ≈ 10(11 prokaryotes per gram in the sand filter along with abiotic and biotic particulates accumulated in the interstitial spaces. Bacteria (up to 90% dominated the biofilm microbial community, with Alphaproteobacteria being the most common class. Thaumarchaeota was the sole phylum of Archaea, which might be involved in ammonia oxidation. Function annotation of metagenomic datasets revealed a number of aromatic degradation pathway genes, such as aromatic oxygenase and dehydrogenase genes, in the biofilm, suggesting a significant role for microbes in the breakdown of aromatic compounds in groundwater. Simultaneous nitrification and denitrification pathways were confirmed as the primary routes of nitrogen removal. Dissolved heavy metals in groundwater, e.g. Mn(2+ and As(3+, might be biologically oxidized to insoluble or easily adsorbed compounds and deposited in the sand filter. Our study demonstrated that the role of the microbial community in the sand filter treatment system are critical to effective water purification in drinking water.

Integrated metagenomic and physiochemical analyses to evaluate the potential role of microbes in the sand filter of a drinking water treatment system.

Science.gov (United States)

Bai, Yaohui; Liu, Ruiping; Liang, Jinsong; Qu, Jiuhui

2013-01-01

While sand filters are widely used to treat drinking water, the role of sand filter associated microorganisms in water purification has not been extensively studied. In the current investigation, we integrated molecular (based on metagenomic) and physicochemical analyses to elucidate microbial community composition and function in a common sand filter used to treat groundwater for potable consumption. The results revealed that the biofilm developed rapidly within 2 days (reaching ≈ 10(11) prokaryotes per gram) in the sand filter along with abiotic and biotic particulates accumulated in the interstitial spaces. Bacteria (up to 90%) dominated the biofilm microbial community, with Alphaproteobacteria being the most common class. Thaumarchaeota was the sole phylum of Archaea, which might be involved in ammonia oxidation. Function annotation of metagenomic datasets revealed a number of aromatic degradation pathway genes, such as aromatic oxygenase and dehydrogenase genes, in the biofilm, suggesting a significant role for microbes in the breakdown of aromatic compounds in groundwater. Simultaneous nitrification and denitrification pathways were confirmed as the primary routes of nitrogen removal. Dissolved heavy metals in groundwater, e.g. Mn(2+) and As(3+), might be biologically oxidized to insoluble or easily adsorbed compounds and deposited in the sand filter. Our study demonstrated that the role of the microbial community in the sand filter treatment system are critical to effective water purification in drinking water.

Innovative in-line separators: removal of water or sand in oil/water and gas/liquid/solid pipelines

Energy Technology Data Exchange (ETDEWEB)

Jepson, Paul; Cheolho Kang; Gopal, Madan [CC Technologies, Dublin, OH (United States)

2003-07-01

In oil and gas production, multiphase mixtures are often separated before downstream processing. The separators are large, often 20 - 40 feet long and large diameter and use sophisticated internals. The costs are in the millions of dollars. Further, the sand and water in the flow can cause severe internal erosion and corrosion respectively before the flow reaches the separators. The CC Technologies/MIST In line Separation System is a cost-effective, efficient device for use in multiphase environments. The device is applicable for gas/solid, gas/liquid/solid and oil/water systems and offers exceptional separation between phases for a fraction of the cost of expensive gravity separators and hydro cyclones. The System contains no moving parts and is designed to be of the same diameter as the pipe, and experiences low shear forces. It can be fabricated with standard pipes. The efficiency of the separator has been determined in an industrial scale, pilot plant test facility at CC Technologies in 4-inch diameter pipes and has been found to be in excess of 98-99% for the removal of sand. Two phase oil/water separation effectiveness is in excess of 90% in 1-stage and 95% in 2 - stage. (author)

Effects of biochar, waste water irrigation and fertilization on soil properties in West African urban agriculture.

Science.gov (United States)

Häring, Volker; Manka'abusi, Delphine; Akoto-Danso, Edmund K; Werner, Steffen; Atiah, Kofi; Steiner, Christoph; Lompo, Désiré J P; Adiku, Samuel; Buerkert, Andreas; Marschner, Bernd

2017-09-06

In large areas of sub-Saharan Africa crop production must cope with low soil fertility. To increase soil fertility, the application of biochar (charred biomass) has been suggested. In urban areas, untreated waste water is widely used for irrigation because it is a nutrient-rich year-round water source. Uncertainty exists regarding the interactions between soil properties, biochar, waste water and fertilization over time. The aims of this study were to determine these interactions in two typical sandy, soil organic carbon (SOC) and nutrient depleted soils under urban vegetable production in Tamale (Ghana) and Ouagadougou (Burkina Faso) over two years. The addition of biochar at 2 kg m -2 made from rice husks and corn cobs initially doubled SOC stocks but SOC losses of 35% occurred thereafter. Both biochar types had no effect on soil pH, phosphorous availability and effective cation exchange capacity (CEC) but rice husk biochar retained nitrogen (N). Irrigation with domestic waste water increased soil pH and exchangeable sodium over time. Inorganic fertilization alone acidified soils, increased available phosphorous and decreased base saturation. Organic fertilization increased SOC, N and CEC. The results from both locations demonstrate that the effects of biochar and waste water were less pronounced than reported elsewhere.

Application of TIE's in assessing toxicity associated with oil sands process waters

International Nuclear Information System (INIS)

MacKinnon, M.

1998-01-01

The hot water digestion process which separates bitumen from oil sands produces large volumes of process-affected waters which are extremely toxic to aquatic organisms. At Syncrude Canada's northeastern Alberta plant, the toxic waters are contained on the site and none are discharged. Organic acids, hydrocarbons and salts are leached into the tailings waters. A toxicity identification evaluation (TIE) test was used to confirm the main contributors to the acute toxicity in these waters. A battery bioassay approach as well as field and laboratory testing was used to understand the source, pathway and duration of the toxicity. Bioassays helped in developing ways in which to mitigate toxicity issues in both reclamation and operational waters. It was demonstrated that natural bioremediation of process-affected waters can reduce acute and chronic toxicity. The long term reclamation impacts of these waters has yet to be determined

Household Fertilizers Use and Soil Fertility Management Practices ...

African Journals Online (AJOL)

Household Fertilizers Use and Soil Fertility Management Practices in Vegetable Crops Production: The Case of Central Rift Valley of Ethiopia. ... rate, which could leads to pollution of the environment from over dose application and from runoff in to the water bodies and leaching in to the ground water with economic loss.

Water consumption characteristics and water use efficiency of winter wheat under long-term nitrogen fertilization regimes in northwest China.

Directory of Open Access Journals (Sweden)

Yangquanwei Zhong

Full Text Available Water shortage and nitrogen (N deficiency are the key factors limiting agricultural production in arid and semi-arid regions, and increasing agricultural productivity under rain-fed conditions often requires N management strategies. A field experiment on winter wheat (Triticum aestivum L. was begun in 2004 to investigate effects of long-term N fertilization in the traditional pattern used for wheat in China. Using data collected over three consecutive years, commencing five years after the experiment began, the effects of N fertilization on wheat yield, evapotranspiration (ET and water use efficiency (WUE, i.e. the ratio of grain yield to total ET in the crop growing season were examined. In 2010, 2011 and 2012, N increased the yield of wheat cultivar Zhengmai No. 9023 by up to 61.1, 117.9 and 34.7%, respectively, and correspondingly in cultivar Changhan No. 58 by 58.4, 100.8 and 51.7%. N-applied treatments increased water consumption in different layers of 0-200 cm of soil and thus ET was significantly higher in N-applied than in non-N treatments. WUE was in the range of 1.0-2.09 kg/m3 for 2010, 2011 and 2012. N fertilization significantly increased WUE in 2010 and 2011, but not in 2012. The results indicated the following: (1 in this dryland farming system, increased N fertilization could raise wheat yield, and the drought-tolerant Changhan No. 58 showed a yield advantage in drought environments with high N fertilizer rates; (2 N application affected water consumption in different soil layers, and promoted wheat absorbing deeper soil water and so increased utilization of soil water; and (3 comprehensive consideration of yield and WUE of wheat indicated that the N rate of 270 kg/ha for Changhan No. 58 was better to avoid the risk of reduced production reduction due to lack of precipitation; however, under conditions of better soil moisture, the N rate of 180 kg/ha was more economic.

Experimental investigation of sanding propensity for the Andrew completion

Energy Technology Data Exchange (ETDEWEB)

Venkitaraman, A.; Li, H. [Schlumberger Perforating and Testing Center (United Kingdom); Leonard, A. J.; Bowden, P. R. [BP Exploration (United Kingdom)

1998-12-31

A series of laboratory experiments were performed on three reservoir core samples selected from two plot wells to confirm the likelihood of sand production during the completion phase of the planned Andrew horizontal wells, and to perform risk analysis of formation failure at the time of underbalance perforation, and expected producing conditions. CT scans revealed no perforation failure, and the core samples did not show any propensity to produce sand during single-phase oil flow. Transient sand production was observed when water cut was introduced, but sand production declined as the percentage of water cut was increased. There was no evidence of sand production in the core samples during depletion testing either, and the wells were subsequently completed with perforated cemented liners without sand control. No sand problems have been encountered in two years of production, with some wells in water cut and declined reservoir pressure of 200 psi. 8 refs., 3 tabs., 5 figs.

Using stable isotopes to determine seasonal variations in water uptake of summer maize under different fertilization treatments

Energy Technology Data Exchange (ETDEWEB)

Ma, Ying, E-mail: maying@igsnrr.ac.cn [Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101 Beijing (China); State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 210008 Nanjing (China); Song, Xianfang [Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101 Beijing (China)

2016-04-15

Fertilization and water both affect root water uptake in the nutrient and water cycle of the Soil-Plant-Atmosphere-Continuum (SPAC). In this study, dual stable isotopes (D and {sup 18}O) were used to determine seasonal variations in water uptake patterns of summer maize under different fertilization treatments in Beijing, China during 2013–2014. The contributions of soil water at different depths to water uptake were quantified by the MixSIAR Bayesian mixing model. Water uptake was mainly sourced from soil water in the 0–20 cm depth at the seeding (67.7%), jointing (60.5%), tasseling (47.5%), dough (41.4%), and harvest (43.9%) stages, and the 20–50 cm depth at the milk stage (32.8%). Different levels of fertilization application led to considerable differences in the proportional contribution of soil water at 0–20 cm (6.0–58.5%) and 20–50 cm (6.1–26.3%). There was little difference of contributions in the deep layers (50–200 cm) among treatments in 2013, whereas differences were observed in 50–90 cm at the milk stage and 50–200 cm at the dough stage during 2014. The main water uptake depth was concentrated in the upper soil layers (0–50 cm) during the wet season (2013), whereas a seasonal drought in 2014 promoted the contribution of soil water in deep layers. The contribution of soil water was significantly and positively correlated with the proportions of root length (r = 0.753, p < 0.01). The changes of soil water distribution were consistent with the seasonal variation in water uptake patterns. The present study identified water sources for summer maize under varying fertilization treatments and provided scientific implications for fertilization and irrigation management. - Highlights: • Dual stable isotopes and MixSIAR were coupled to quantify water uptake of maize. • Maize mainly used soil water in 20–50 cm at milk stage and 0–20 cm at other stages. • Fertilization treatments led to distinct water uptake pattern at 0–50 cm

Using stable isotopes to determine seasonal variations in water uptake of summer maize under different fertilization treatments

International Nuclear Information System (INIS)

Ma, Ying; Song, Xianfang

2016-01-01

Fertilization and water both affect root water uptake in the nutrient and water cycle of the Soil-Plant-Atmosphere-Continuum (SPAC). In this study, dual stable isotopes (D and "1"8O) were used to determine seasonal variations in water uptake patterns of summer maize under different fertilization treatments in Beijing, China during 2013–2014. The contributions of soil water at different depths to water uptake were quantified by the MixSIAR Bayesian mixing model. Water uptake was mainly sourced from soil water in the 0–20 cm depth at the seeding (67.7%), jointing (60.5%), tasseling (47.5%), dough (41.4%), and harvest (43.9%) stages, and the 20–50 cm depth at the milk stage (32.8%). Different levels of fertilization application led to considerable differences in the proportional contribution of soil water at 0–20 cm (6.0–58.5%) and 20–50 cm (6.1–26.3%). There was little difference of contributions in the deep layers (50–200 cm) among treatments in 2013, whereas differences were observed in 50–90 cm at the milk stage and 50–200 cm at the dough stage during 2014. The main water uptake depth was concentrated in the upper soil layers (0–50 cm) during the wet season (2013), whereas a seasonal drought in 2014 promoted the contribution of soil water in deep layers. The contribution of soil water was significantly and positively correlated with the proportions of root length (r = 0.753, p < 0.01). The changes of soil water distribution were consistent with the seasonal variation in water uptake patterns. The present study identified water sources for summer maize under varying fertilization treatments and provided scientific implications for fertilization and irrigation management. - Highlights: • Dual stable isotopes and MixSIAR were coupled to quantify water uptake of maize. • Maize mainly used soil water in 20–50 cm at milk stage and 0–20 cm at other stages. • Fertilization treatments led to distinct water uptake pattern at 0–50 cm depth

Field test on sand compaction pile method with copper slag sand; Dosuisai slag wo mochiita SCP koho no shiken seko

Energy Technology Data Exchange (ETDEWEB)

Minami, K.; Matsui, H.; Naruse, E.; Kitazume, M. [Port and Harbour Research Inst., Kanagawa (Japan)

1997-09-20

This paper describes the sand compaction pile (SCP) method using copper slag sand. The SCP method is a method by which sand compaction piles are constructed in the ground, and improvement can be obtained in a short period. This method has been widely used even in the port areas for enhancing the bearing power of soft clay ground and the lateral resistance of sheet pile. A great deal of sand is required as a material. The sand requires high permeability, proper size distribution with less fine particle fraction content, easy compaction property with enough strength, and easy discharging property from the casing of construction machines as required properties. Recently, it becomes hard to secure proper sand materials. The copper slag sand is obtained from refining process of copper as a by-product which is quenched in water flow and crushed in water. The copper slag sand has higher particle density than that of sand, excellent permeability, and similar size distribution to that of sand. From compaction drainage triaxial compression test and permeability test, it was found that the mechanical properties of copper slag sand did not change by the crushing of grains with keeping excellent permeability. Through the test construction, applicability of the copper slag sand to the SCP method could be confirmed as an alternate material of sand. 17 refs., 9 figs., 4 tabs.

Investigation of Dynamic Properties of Water-Saturated Sand by the Results of the Inverse Experiment Technique

Science.gov (United States)

Bragov, A. M.; Balandin, Vl. V.; Kotov, V. L.; Balandin, Vl. Vl.

2018-04-01

We present new experimental results on the investigation of the dynamic properties of sand soil on the basis of the inverse experiment technique using a measuring rod with a flat front-end face. A limited applicability has been shown of the method using the procedure for correcting the shape of the deformation pulse due to dispersion during its propagation in the measuring rod. Estimates of the pulse maximum have been obtained and the results of comparison of numerical calculations with experimental data are given. The sufficient accuracy in determining the drag force during the quasi-stationary stage of penetration has been established. The parameters of dynamic compressibility and resistance to shear of water-saturated sand have been determined in the course of the experimental-theoretical analysis of the maximum values of the drag force and its values at the quasi-stationary stage of penetration. It has been shown that with almost complete water saturation of sand its shear properties are reduced but remain significant in the practically important range of penetration rates.

The Effect of Water Cement Ratio on Cement Brick Containing High Density Polyethylene (HDPE as Sand Replacement

Directory of Open Access Journals (Sweden)

Ali Noorwirdawati

2018-01-01

Full Text Available Waste disposal can contribute to the problem of environmental pollution. Most of the waste material is plastic based, because the nature of difficult of plastic degradable by itself. In order to overcome the problem, many study has been conducted on the reuse of plastic material into various field such as civil engineering and construction. In this study, municipal solid waste (MSW in the form of High Density Polyethylene (HDPE plastic was used to replace sand in cement sand brick production. The HDPE used in this study was obtained from a recycle factory at Nilai, Negeri Sembilan. 3% of HDPE replacement was applied in this study, with the cement-sand mix design of 1:6 and water-cement ratio 0.35, 0.40, 0.45 and 0.50 respectively. All specimens were tested for compressive strength and water absorption at 7 and 28 days. The density of the bricks was also recorded. The finding show that brick with 3% HDPE content and 0.45 of water-cement ratio at 28 days of age curing show the highest compressive strength, which is 19.5N/mm2 compared to the control specimen of 14.4 N/mm2.

Predictive hydrogeochemical modelling of bauxite residue sand in field conditions.

Science.gov (United States)

Wissmeier, Laurin; Barry, David A; Phillips, Ian R

2011-07-15

The suitability of residue sand (the coarse fraction remaining from Bayer's process of bauxite refining) for constructing the surface cover of closed bauxite residue storage areas was investigated. Specifically, its properties as a medium for plant growth are of interest to ensure residue sand can support a sustainable ecosystem following site closure. The geochemical evolution of the residue sand under field conditions, its plant nutrient status and soil moisture retention were studied by integrated modelling of geochemical and hydrological processes. For the parameterization of mineral reactions, amounts and reaction kinetics of the mineral phases natron, calcite, tricalcium aluminate, sodalite, muscovite and analcime were derived from measured acid neutralization curves. The effective exchange capacity for ion adsorption was measured using three independent exchange methods. The geochemical model, which accounts for mineral reactions, cation exchange and activity corrected solution speciation, was formulated in the geochemical modelling framework PHREEQC, and partially validated in a saturated-flow column experiment. For the integration of variably saturated flow with multi-component solute transport in heterogeneous 2D domains, a coupling of PHREEQC with the multi-purpose finite-element solver COMSOL was established. The integrated hydrogeochemical model was applied to predict water availability and quality in a vertical flow lysimeter and a cover design for a storage facility using measured time series of rainfall and evaporation from southwest Western Australia. In both scenarios the sand was fertigated and gypsum-amended. Results show poor long-term retention of fertilizer ions and buffering of the pH around 10 for more than 5 y of leaching. It was concluded that fertigation, gypsum amendment and rainfall leaching alone were insufficient to render the geochemical conditions of residue sand suitable for optimal plant growth within the given timeframe. The

Proper Management Of Irrigation Water And Nitrogen Fertilizer To Improve Spinach Yield And Reserve Environment Using 15N Tracer Technique

International Nuclear Information System (INIS)

GADALLA, A.M.; GALAL, Y.G.M.; ISMAIL, M.M.; EL DEGWY, S.A.; HAMDY, A.; HAMED, L.M.

2010-01-01

The effect of water regime and N-fertilizer application rate and modality of its application were studied by the aim of identifying the most proper and effective combination of the above studied variables that provide a satisfactory spinach yield as well as to minimize the rational use of chemical nitrogen fertilizers to save the surrounding environment and to achieve a good water saving. The results indicated that reasonable production of spinach crop could be achieved by using 75% of the recommended rate of nitrogen fertilizer combined with 80% of the required water. It means that 20% of the required water could be saved as well as 25% of the required quantity of N-fertilizer. Similarly, the splitting of N-fertilizer into two equal doses prevented the excess of nitrate to be moved to the underground water lowering its concentration in the blades and plant leaves. Drip irrigation system accompanied with proper water scheduling regime and good fertilizer application practices is considered as a useful management practice that could be applied to improve the sandy soil productivity.

Measurements of distribution coefficient for U and Th on sand stone in synthesized sea water and distilled water

International Nuclear Information System (INIS)

Nakazawa, Toshiyuki; Okada, Kenichi; Saito, Yoshihiko; Shibata, Masahiro; Sasamoto, Hiroshi

2005-01-01

Japan Nuclear Cycle Development Institute (JNC) has developed the sorption database for bentonite and rocks in order to assess the retardation property of important radioactive elements in natural and engineered barriers in the H12 report. However, there are not enough distribution coefficient data for radioactive elements in saline type groundwater in the database. Thus the batch sorption tests were performed for uranium (U) and thorium (Th) in saline type groundwater. For these elements, there are little registration numbers in the JNC's sorption database, and also these elements are important to evaluate the safety of disposal system. The experiments for each radioactive element were performed on the following conditions; U: Kd measurements using the solutions (synthesized sea water and distilled water) reacted with sand stone as a function of carbonate concentration, under reducing conditions. Th: Kd measurements using the solutions (synthesized sea water and distilled water) reacted with sand stone. The results of the experiments are summarized below; In the case of U, Kd was approximately 6.5E-01 - 9.2E-01 m 3 /kg in synthesized sea water. On the other hand, Kd was 2.2E-02 - 2.4E-02 m 3 /kg in the high carbonate solution. And also, Kd was 6.5E-02 - 7.2E-02 m 3 /kg in synthesized sea water adjusted pH 10 and 3.4E-02 - 4.1E-02 m 3 /kg in distilled water adjusted pH 10, respectively. In the case of Th, Kd was measured in synthesized sea water adjusted to pH 10 and in distilled water adjusted to pH 10. At the sorption measurements of Th, precipitation might be occurred by very low solubility of Th. (author)

Hydrogeologic characteristics and water quality of a confined sand unit in the surficial aquifer system, Hunter Army Airfield, Chatham County, Georgia

Science.gov (United States)

Gonthier, Gerard

2012-01-01

An 80-foot-deep well (36Q397, U.S. Geological Survey site identification 320146081073701) was constructed at Hunter Army Airfield to assess the potential of using the surficial aquifer system as a water source to irrigate a ballfield complex. A 300-foot-deep test hole was drilled beneath the ballfield complex to characterize the lithology and water-bearing characteristics of sediments above the Upper Floridan aquifer. The test hole was then completed as well 36Q397 open to a 19-foot-thick shallow, confined sand unit contained within the surficial aquifer system. A single-well, 24-hour aquifer test was performed by pumping well 36Q397 at a rate of 50 gallons per minute during July 13-14, 2011, to characterize the hydrologic properties of the shallow, confined sand unit. Two pumping events prior to the aquifer test affected water levels. Drawdown during all three pumping events and residual drawdown during recovery periods were simulated using the Theis formula on multiple changes in discharge rate. Simulated drawdown and residual drawdown match well with measured drawdown and residual drawdown using values of horizontal hydraulic conductivity and specific storage, which are typical for a confined sand aquifer. Based on the hydrologic parameters used to match simulated drawdown and residual drawdown to measured drawdown and residual drawdown, the transmissivity of the sand was determined to be about 400 feet squared per day. The horizontal hydraulic conductivity of the sand was determined to be about 20 feet per day. Analysis of a water-quality sample indicated that the water is suitable for irrigation. Sample analysis indicated a calcium-carbonate type water having a total dissolved solids concentration of 39 milligrams per liter. Specific conductance and concentrations of all analyzed constituents were below those that would be a concern for irrigation, and were below primary and secondary water-quality criteria levels.

Reuse of waste cutting sand at Lawrence Livermore National Laboratory

International Nuclear Information System (INIS)

Mathews, S.; Wilson, K.

1998-01-01

Lawrence Livermore National Laboratory (LLNL) examined the waste stream from a water jet cutting operation, to evaluate the possible reuse of waste garnet sand. The sand is a cutting agent used to shape a variety of materials, including metals. Nearly 70,000 pounds of waste sand is generated annually by the cutting operation. The Environmental Protection Department evaluated two potential reuses for the spent garnet sand: backfill in utility trenches; and as a concrete constituent. In both applications, garnet waste would replace the sand formerly purchased by LLNL for these purposes. Findings supported the reuse of waste garnet sand in concrete, but disqualified its proposed application as trench backfill. Waste sand stabilized in a concrete matrix appeared to present no metals-leaching hazard; however, unconsolidated sand in trenches could potentially leach metals in concentrations high enough to threaten ground water quality. A technical report submitted to the San Francisco Bay Regional Water Quality Control Board was reviewed and accepted by that body. Reuse of waste garnet cutting sand as a constituent in concrete poured to form walkways and patios at LLNL was approved

Effects of the spermatozoa: oocyte ratio, water volume and water temperature on artificial fertilization and sperm activation of cascudo-preto

Directory of Open Access Journals (Sweden)

Robie Allan Bombardelli

2013-01-01

Full Text Available The objective of this study was to evaluate the effects of water volume and water temperature on the sperm motility duration and the number of spermatozoa, and the water volume on the fertilization rates of oocytes of Rhinelepis aspera. Experiments were carried out to evaluate the effect of semen dilutions (1.74×10-5, 1.74×10-4, 1.74×10-3, 1.74×10-2, 1.74×10-1 and 1.00 mL of sperm.mL-1 of water and water temperature (5, 10, 15, 20, 25, 30, 35, 40, 45, and 50 ºC on spermatozoa motility duration. In addition, the effects of insemination dose (7×10³, 7×10(4, 7×10(5, 7×10(6 and 7×10(7 spermatozoa.oocyte-1 and water volume (1.0, 30.0, 60.0, 90.0 and 120.0 mL water.2.0 mL-1 oocytes on the artificial fertilization rates of oocytes were evaluated. The longest sperm motility duration were observed for the semen dilution of 1.74×10-5 mL semen.mL-1 water and in water at 5 ºC. The highest fertilization rates were obtained for insemination doses between 7.00×10³ and 1.23×10(7 spermatozoa. oocyte-1 and water volume of 28.11 mL water.2.0 mL-1 oocytes.

Sulfate reducing bacteria and their activities in oil sands process-affected water biofilm

Energy Technology Data Exchange (ETDEWEB)

Liu, Hong; Yu, Tong, E-mail: tong.yu@ualberta.ca; Liu, Yang, E-mail: yang.liu@ualberta.ca

2015-12-01

Biofilm reactors were constructed to grow stratified multispecies biofilm in oil sands process-affected water (OSPW) supplemented with growth medium. The development of sulfate reducing bacteria (SRB) within the biofilm and the biofilm treatment of OSPW were evaluated. The community structure and potential activity of SRB in the biofilm were investigated with H{sub 2}S microsensor measurements, dsrB gene-based denaturing gradient gel electrophoresis (DGGE), and the real time quantitative polymerase chain reaction (qPCR). Multispecies biofilm with a thickness of 1000 μm was successfully developed on engineered biocarriers. H{sub 2}S production was observed in the deeper anoxic zone of the biofilm from around 750 μm to 1000 μm below the bulk water-biofilm interface, revealing sulfate reduction in the deeper zone of the stratified biofilm. The biofilm removed chemical oxygen demand (COD), sulfate, and nitrogen. The study expands current knowledge of biofilm treatment of OSPW and the function of anaerobic SRB in OSPW biofilm, and thus provides information for future bioreactor development in the reclamation of OSPW. - Graphical abstract: The development of sulfate reducing bacteria (SRB) within Oil Sands Process-affected Water (OSPW) biofilm and the biofilm treatment of OSPW were evaluated by Liu and coworkers. Combined microsensor and molecular biology techniques were utilized in this study. Their results demonstrated that multispecies biofilm with a thickness of 1000 μm was successfully developed on engineered biocarriers. H{sub 2}S production was observed in the deeper anoxic zone of the biofilm from around 750 μm to 1000 μm below the bulk water-biofilm interface, revealing sulfate reduction in the deeper zone of the biofilm. The biofilm removed chemical oxygen demand (COD), sulfate, and nitrogen. - Highlights: • Biofilm in oil sands wastewater was developed on engineered biocarriers. • Bacterial community and in situ activity of SRB were studied in the

Sulfate reducing bacteria and their activities in oil sands process-affected water biofilm

International Nuclear Information System (INIS)

Liu, Hong; Yu, Tong; Liu, Yang

2015-01-01

Biofilm reactors were constructed to grow stratified multispecies biofilm in oil sands process-affected water (OSPW) supplemented with growth medium. The development of sulfate reducing bacteria (SRB) within the biofilm and the biofilm treatment of OSPW were evaluated. The community structure and potential activity of SRB in the biofilm were investigated with H 2 S microsensor measurements, dsrB gene-based denaturing gradient gel electrophoresis (DGGE), and the real time quantitative polymerase chain reaction (qPCR). Multispecies biofilm with a thickness of 1000 μm was successfully developed on engineered biocarriers. H 2 S production was observed in the deeper anoxic zone of the biofilm from around 750 μm to 1000 μm below the bulk water-biofilm interface, revealing sulfate reduction in the deeper zone of the stratified biofilm. The biofilm removed chemical oxygen demand (COD), sulfate, and nitrogen. The study expands current knowledge of biofilm treatment of OSPW and the function of anaerobic SRB in OSPW biofilm, and thus provides information for future bioreactor development in the reclamation of OSPW. - Graphical abstract: The development of sulfate reducing bacteria (SRB) within Oil Sands Process-affected Water (OSPW) biofilm and the biofilm treatment of OSPW were evaluated by Liu and coworkers. Combined microsensor and molecular biology techniques were utilized in this study. Their results demonstrated that multispecies biofilm with a thickness of 1000 μm was successfully developed on engineered biocarriers. H 2 S production was observed in the deeper anoxic zone of the biofilm from around 750 μm to 1000 μm below the bulk water-biofilm interface, revealing sulfate reduction in the deeper zone of the biofilm. The biofilm removed chemical oxygen demand (COD), sulfate, and nitrogen. - Highlights: • Biofilm in oil sands wastewater was developed on engineered biocarriers. • Bacterial community and in situ activity of SRB were studied in the biofilm. �

Hydrogeochemical contrast between brown and grey sand aquifers in shallow depth of Bengal Basin: consequences for sustainable drinking water supply.

Science.gov (United States)

Biswas, Ashis; Nath, Bibhash; Bhattacharya, Prosun; Halder, Dipti; Kundu, Amit K; Mandal, Ujjal; Mukherjee, Abhijit; Chatterjee, Debashis; Mörth, Carl-Magnus; Jacks, Gunnar

2012-08-01

Delineation of safe aquifer(s) that can be targeted by cheap drilling technology for tubewell (TW) installation becomes highly imperative to ensure access to safe and sustainable drinking water sources for the arsenic (As) affected population in Bengal Basin. This study investigates the potentiality of brown sand aquifers (BSA) as a safe drinking water source by characterizing its hydrogeochemical contrast to grey sand aquifers (GSA) within shallow depth (water guidelines, which warrants rigorous assessment of attendant health risk for Mn prior to considering mass scale exploitation of the BSA for possible sustainable drinking water supply. Copyright © 2012 Elsevier B.V. All rights reserved.

Study on the quantitative relationship between Agricultural water and fertilization process and non-point source pollution based on field experiments

Science.gov (United States)

Wang, H.; Chen, K.; Wu, Z.; Guan, X.

2017-12-01

In recent years, with the prominent of water environment problem and the relative increase of point source pollution governance, especially the agricultural non-point source pollution problem caused by the extensive use of fertilizers and pesticides has become increasingly aroused people's concern and attention. In order to reveal the quantitative relationship between agriculture water and fertilizer and non-point source pollution, on the basis of elm field experiment and combined with agricultural drainage irrigation model, the agricultural irrigation water and the relationship between fertilizer and fertilization scheme and non-point source pollution were analyzed and calculated by field emission intensity index. The results show that the variation of displacement varies greatly under different irrigation conditions. When the irrigation water increased from 22cm to 42cm, the irrigation water increased by 20 cm while the field displacement increased by 11.92 cm, about 66.22% of the added value of irrigation water. Then the irrigation water increased from 42 to 68, irrigation water increased 26 cm, and the field displacement increased by 22.48 cm, accounting for 86.46% of irrigation water. So there is an "inflection point" between the irrigation water amount and field displacement amount. The load intensity increases with the increase of irrigation water and shows a significant power correlation. Under the different irrigation condition, the increase amplitude of load intensity with the increase of irrigation water is different. When the irrigation water is smaller, the load intensity increase relatively less, and when the irrigation water increased to about 42 cm, the load intensity will increase considerably. In addition, there was a positive correlation between the fertilization and load intensity. The load intensity had obvious difference in different fertilization modes even with same fertilization level, in which the fertilizer field unit load intensity

Interaction between N-fertilizer and water availability on borer-rot complex in sugarcane

Directory of Open Access Journals (Sweden)

Luiz Eduardo da Rocha Pannuti

2015-03-01

Full Text Available This study aimed to evaluate the effects of nitrogen availability in fertigation and rainfed management, as well as their interactions with the incidence of and damage caused by D. saccharalis and red rot in sugarcane. The experiment consisted of four treatments (0 and 150 kg ha–1 of N-fertilizer with irrigation; 0 and 150 kg ha–1 of N-fertilizer in rainfed management in a randomized complete block design with four replications. The evaluated parameters were the number of holes and internodes with red rot per meter of cultivation, stalk yield and sugar content. In the laboratory (T = 25 ± 2 °C; R.H. = 70 ± 10%: 12:12-L:D, we evaluated the attractiveness and consumption of fragments of stalks from the different treatments for fourth instar larvae through choice and no-choice tests in a randomized complete block design with ten replications. Nitrogen fertilization via irrigation has favorable effects on borer-rot complex and leads to higher gains in stalk and sugar yields when compared to rainfed management. The increments of stalk and sugar yields due to nitrogen fertilization compensates for the increase in borer-rot complex infestation. In laboratory tests, D. saccharalis larvae were similarly attracted to all treatments regardless of the doses of N-fertilizer or the water regimes evaluated. However, fragments of sugarcane stalks produced with nitrogen fertilization were consumed more by D. saccharalis in both water regimes.

Chemical mass transport between fluid fine tailings and the overlying water cover of an oil sands end pit lake

Science.gov (United States)

Dompierre, Kathryn A.; Barbour, S. Lee; North, Rebecca L.; Carey, Sean K.; Lindsay, Matthew B. J.

2017-06-01

Fluid fine tailings (FFT) are a principal by-product of the bitumen extraction process at oil sands mines. Base Mine Lake (BML)—the first full-scale demonstration oil sands end pit lake (EPL)—contains approximately 1.9 × 108 m3 of FFT stored under a water cover within a decommissioned mine pit. Chemical mass transfer from the FFT to the water cover can occur via two key processes: (1) advection-dispersion driven by tailings settlement; and (2) FFT disturbance due to fluid movement in the water cover. Dissolved chloride (Cl) was used to evaluate the water cover mass balance and to track mass transport within the underlying FFT based on field sampling and numerical modeling. Results indicated that FFT was the dominant Cl source to the water cover and that the FFT is exhibiting a transient advection-dispersion mass transport regime with intermittent disturbance near the FFT-water interface. The advective pore water flux was estimated by the mass balance to be 0.002 m3 m-2 d-1, which represents 0.73 m of FFT settlement per year. However, the FFT pore water Cl concentrations and corresponding mass transport simulations indicated that advection rates and disturbance depths vary between sample locations. The disturbance depth was estimated to vary with location between 0.75 and 0.95 m. This investigation provides valuable insight for assessing the geochemical evolution of the water cover and performance of EPLs as an oil sands reclamation strategy.

Effect of Various Organic Fertilizers Substitute Chemical Fertilizer on Cucumber Productions

International Nuclear Information System (INIS)

Piadang, Nattayana; Ratanapanit, Sittisuk; Chaowanklang, Pratuang; Ratanapanit; Nadtinee; Jaipakdee, Putinee; Ongsakitboriboon

2006-09-01

The effect of using the various organic fertilizer to substitute on the chemical fertilizer on cucumber, was carried out at Tambol Pattananikom, Amphur Pattananikom, Lopburi, Thailand, from December 1, 2005 to February 1, 2006 By using Randomized Comp let Block Design (RCBD), Contain with 4 treatments, chemical fertilizer: 16-16-16: 40 Kg/rai (Control), Pillet organic fertilizer: 50 Kg/rai, Bio extract from cow milk: 300 cc./ water 20 Ltr,.+ compost mixed in soil and bio fertilizer from the office of Atomic Energy Peace : 300 cc./water 20 Ltr. + campost mixed in soil (15 m. 2 /plot) were compared. Experiment result indicate that there were no significant differences on the yield. The highest yield of 25.91 kg/plot (27663.73 kg/rai) was obtained from chemical fertilizer, Fertilizer, followed by pillet organic fertilizer 22.88 kg/plot (2440.53 kg/rai), bio fertilizer 22.34 kg/pot (2382.93 kg/rai) and bio extract 19.03 kg/plot) (2029.87 kg/rai.

Biostimulants and Its Potential Utilization in Functional Water-soluble Fertilizers

Directory of Open Access Journals (Sweden)

ZHANG Qiang

2018-02-01

Full Text Available Biostimulants are becoming widely applied and extended in the fertilizer industry, because of their effects on soil improvement, anti-stress ability enhancement and root growth promotion, which can increase efficient uptake and utilization of soil nutrients, crop yield and quality.This review introduced the concepts of biostimulants, and summarized the functions and related mechanisms of commonly-applied biostimulants in the market, i.e.humic acid, amino acid, seaweed extracts and plant-growth-promoting bacteria(PGPR. The properties and applied characteristics of different organic wastes containing some biostimulating compounds as the main material of functional water soluble fertilizers (WSFin the industry were presented. The technical keys to compound these organic wastes with some bio-active substances to produce the functional WSF were explored, with the aims to support the value -added utilization of organic wastes, reduce the use of fertilizers, and promote crops忆 quality and quantity.

Investigations on organics in the Libyan beach sand and water: extraction, spectroscopy and gas chromatography, Zwarah to East Tripoli coastline

International Nuclear Information System (INIS)

Ali, L.H.; El-Jawashi, S.A.; Ejbali, A.A.; Garbaj, M.J.

1998-01-01

Forty-three samples from fifteen locations extending along 200 kilometers from near the Tunisian borders to 20 kilometers east of Tripoli harbour were examined for their organic contents. Sampling was conducted under the following specifications. 1. Dry beach sand, 3-4 meters away from water (denoted ds). 2. Wet beach sand, obtained from 1 meter depth (denoted ws). 3. Beach water (denoted w). Known amounts of sand (ds or ws) and beach water (w) were extracted with a suitable volume of chloroform. Organics in the extracts were determined gravimetrically by complete evaporation of chloroform, the residue was further examined by gas chromatography, and distribution of carbon numbers in each sample were assessed. Alternatively, a direct determination of organics concentration in CHCl 3 solution was obtained spectrophotometrically from calibration curves of absorptions at 410nm and 260nm. Infrared study on organics isolated from different locations enabled the assessment of the degree of oxidation suffered by each sample. This was obtained by comparing the relative absorption values at 1736 and 1712cm -1 , normalized with respect to 2925 cm -1 ; C-H stretching vibration; to rule out effects due to concentration. Organics concentration in shore water ranged from 0.05 to 9.50 ppm, depending on location and industrial activities, while much higher concentrations, ranging from 50-1500 ppm were detected in dry and wet beach sand samples. (author)

Phosphorus loss to runoff water twenty-four hours after application of liquid swine manure or fertilizer.

Science.gov (United States)

Tabbara, Hadi

2003-01-01

Phosphorus (P) added to soil from fertilizer or manure application could pose a threat to water quality due to its role in eutrophication of fresh water resources. Incorporating such amendments into the soil is an established best management practice (BMP) for reducing soluble P losses in runoff water, but could also lead to higher erosion. The objective of this study was to test whether incorporation of manure or fertilizer 24 h before an intense rain could also reduce sediment-bound and total phosphorus (TP) losses in runoff. A rainfall simulation study was conducted on field plots (sandy loam with 6-7% slope, little surface residue, recently cultivated) that received two application rates of liquid swine manure or liquid ammonium polyphosphate fertilizer, using either surface-broadcast or incorporated methods of application. Incorporation increased the total suspended solids (TSS) concentrations in runoff but mass losses were not affected. Incorporation also reduced flow-weighted concentrations and losses of dissolved reactive phosphorus (DRP) and TP by as much as 30 to 60% depending on source (fertilizer vs. manure) and application rate. Phosphorus is moved below the mixing zone of interaction on incorporation, and thus the effect of the amount and availability of P in this zone is more important than cultivation on subsequent P losses in runoff. Incorporating manure or fertilizer in areas of intense erosive rain, recent extensive tillage, and with little or no surface residue is therefore a best management practice that should be adhered to in order to minimize contamination of surface water. Results also show comparatively lower P losses from manure than fertilizer.

Isotopic and geochemical tracers for fingerprinting process-affected waters in the oil sands industry: a pilot study

Energy Technology Data Exchange (ETDEWEB)

Gibson, J.J.; Birks, S.J.; Moncur, M.; Yi, Y.; Tattrie, K.; Jasechko, S.; Richardson, K.; Eby, P. [Alberta Innovates - Technology Futures (Canada)

2011-04-15

During 2009 and 2010, Alberta Innovates - Technology Futures carried out a pilot study for Alberta Environment to examine the possibility of labeling process affected water from oil sands operations with isotropic and geochemical tracers. For the study, 3 oil sands operators furnished logistical support and personnel, 39 samples were gathered and several isotope tracers were measured. In addition, geotechnical analyses were performed and the presence of organic compounds in the samples was scanned using Fourier transform ion cyclotron resonance mass spectrometry. Results showed that the selected tracers were able to label water sources in some locations, however they cannot be used as a universal method and a case by case approach needs to be adopted. This study pointed out that Fourier transform ion cyclotron resonance mass spectrometry is the best way to construct a dataset for use in identification of process affected waters.

Release of cadmium in contaminated paddy soil amended with NPK fertilizer and lime under water management.

Science.gov (United States)

Han, Xiao-Qing; Xiao, Xi-Yuan; Guo, Zhao-Hui; Xie, Ye-Hua; Zhu, Hui-Wen; Peng, Chi; Liang, Yu-Qin

2018-05-03

Agricultural soils contaminated with cadmium (Cd) pose a risk to receiving surface water via drainage or runoff. A 90-day laboratory incubation experiment was conducted to investigate the release characteristics and transformation of Cd from contaminated paddy soil amended with agrochemical (NPK fertilizer) and lime (L) under water management regimes of continuous flooding (F) and drying-wetting cycles (DW). The result showed that the dissolved Cd concentrations in overlying water of the fertilizer treatment under flooding (NPK+F) and drying-wetting (NPK+DW) reached up to 81.0 μg/L and 276 μg/L, and were much higher than that from the corresponding controls without NPK fertilizer addition at the end of experiment. The Cd concentration showed significantly negative correlation with overlying water pH, but positive correlation with soil redox potential and concentrations of dissolved total nitrogen, sulfate and manganese in overlying water (P < 0.05), indicating that drying-wetting cycles and N fertilizer addition may enhance soil Cd release. The Cd concentrations in overlying water from all treatments except NPK+L+F treatment exceeded the Cd threshold limit of Chinese Environmental Quality Standards for Surface Water (10 μg/L Grade V) and poses potential risk to surface water quality. Meanwhile, the proportion of Cd in the acid-soluble fraction from all incubated soil except NPK+L+F treatment increased compared to before incubation. The results indicated that continuous flooding was a reasonable water management candidate coupled with lime addition for immobilizing soil Cd. Copyright © 2018 Elsevier Inc. All rights reserved.

Transport processes in intertidal sand flats

Science.gov (United States)

Wu, Christy

2010-05-01

Methane rich sulfate depleted seeps are observed along the low water line of the intertidal sand flat Janssand in the Wadden Sea. It is unclear where in the flat the methane is formed, and how it is transported to the edge of the sand flat where the sulfidic water seeps out. Methane and sulfate distributions in pore water were determined along transects from low water line toward the central area of the sand flat. The resulting profiles showed a zone of methane-rich and sulfate-depleted pore water below 2 m sediment depth. Methane production and sulfate reduction are monitored over time for surface sediments collected from the upper flat and seeping area. Both activities were at 22 C twice as high as at 15 C. The rates in sediments from the central area were higher than in sediments from the methane seeps. Methanogenesis occurred in the presence of sulfate, and was not significantly accelerated when sulfate was depleted. The observations show a rapid anaerobic degradation of organic matter in the Janssand. The methane rich pore water is obviously transported with a unidirectional flow from the central area of the intertidal sand flat toward the low water line. This pore water flow is driven by the pressure head caused by elevation of the pore water relative to the sea surface at low tide (Billerbeck et al. 2006a). The high methane concentration at the low water line accumulates due to a continuous outflow of pore water at the seepage site that prevents penetration of electron acceptors such as oxygen and sulfate to reoxidize the reduced products of anaerobic degradation (de Beer et al. 2006). It is, however, not clear why no methane accumulates or sulfate is depleted in the upper 2 m of the flats.

Enhancing water and fertilizer saving without compromising rice yield through integrated crop management

NARCIS (Netherlands)

Wardana, I.P.; Gani, A.; Abdulrachmann, S.; Bindraban, P.S.; Keulen, van H.

2010-01-01

Water and fertilizer scarcity amid the increasing need of rice production challenges today’s agriculture. Integrated crop management (ICM) is a combination of water, crop, and nutrient management that optimizes the synergistic interaction of these components aiming at improving resource use

Effects of dynamic operating conditions on nitrification in biological rapid sand filters for drinking water treatment

DEFF Research Database (Denmark)

Lee, Carson Odell; Boe-Hansen, Rasmus; Musovic, Sanin

2014-01-01

Biological rapid sand filters are often used to remove ammonium from groundwater for drinking water supply. They often operate under dynamic substrate and hydraulic loading conditions, which can lead to increased levels of ammonium and nitrite in the effluent. To determine the maximum nitrification...... operating conditions. The ammonium removal rate of the filter was determined by the ammonium loading rate, but was independent of both the flow and influent ammonium concentration individually. Ammonia-oxidizing bacteria and archaea were almost equally abundant in the filter. Both ammonium removal...... rates and safe operating windows of rapid sand filters, a pilot scale rapid sand filter was used to test short-term increased ammonium loads, set by varying either influent ammonium concentrations or hydraulic loading rates. Ammonium and iron (flock) removal were consistent between the pilot...

Characterization of waste waters of tannery, fertilizer and textile industries in Multan region

International Nuclear Information System (INIS)

Ansan, T.M.; Malik, S.A.

2001-01-01

This study evaluates various physico-chemical characteristics such as pH, electrical conductivity, dissolved solids, hardness, apparent color, odor, elemental concentrations, chloride contents, carbonates, bicarbonates, residual sodium carbonate and sodium absorption ratio of waste waters of three major industries, i.e. tannery, fertilizer and textile, situated in Multan District of the Punjab province, Pakistan. Waste waters, in general, have been found to be hard, alkaline in nature and contain variable amounts of dissolved solids. High concentration of chromium (10.7 mg 1-1) was found in tannery wastewater. Zinc and copper concentrations were not quantifiable. Water quality classes (C4-S4), (C4-S1) and (C4-S1, C3-S1, C3-S4 and C3-S2) have been assigned to tannery, fertilizer and textile waste waters respectively. Results indicate that these untreated industrial waste waters are potential hazards to human health and unsuitable for irrigation usage. (author)

Origin and geochemistry of saline spring waters in the Athabasca oil sands region, Alberta, Canada

International Nuclear Information System (INIS)

Gue, Anita E.; Mayer, Bernhard; Grasby, Stephen E.

2015-01-01

Highlights: • Saline groundwater enters the Athabasca and Clearwater rivers in the AOSR via springs. • High TDS is due to subsurface dissolution of Devonian evaporites and carbonates. • Low δ 18 O values, and 3 H and 14 C data suggest some Laurentide glacial meltwater input. • Bacterial sulfate reduction, methanogenesis, and CH 4 oxidation were identified. • Metal and PAH contents are reported; bitumen does not appear to be major influence. - Abstract: The geochemistry of saline spring waters in the Athabasca oil sands region (AOSR) in Alberta (Canada) discharging from Devonian carbonate rocks into the Athabasca and Clearwater rivers was characterized for major ions, trace elements, dissolved gases, and polycyclic aromatic hydrocarbons (PAHs). In addition, stable isotope analyses of H 2 O, SO 4 , dissolved inorganic carbon (DIC), Sr, and CH 4 were used to trace the sources of spring waters and their dissolved solutes, and to identify subsurface processes affecting water chemistry. The spring waters had δ 18 O values as low as −23.5‰, suggesting they are composed of up to 75% Laurentide glacial meltwater. Tritium and radiocarbon age-dating results, analyzed for three spring waters, supported a glacial origin. The high salinity of the spring waters (TDS 7210–51,800 mg/L) was due to dissolution of Devonian evaporite and carbonate deposits in the subsurface. Spring waters were affected by bacterial (dissimilatory) sulfate reduction, methanogenesis, and methane oxidation. Trace elements were present in spring waters at varying concentrations, with only one spring containing several predominant oil sands metals (As, Fe, Mo, Ni, Se, Zn) suggesting bitumen as a source. Five springs contained elements (Al, As, B, Fe, Se) at concentrations exceeding water quality guidelines for the protection of aquatic life. Seven PAHs were detected in spring waters (total PAH concentrations ranged from 7.3 to 273.6 ng/L), but most springs contained a maximum of two PAHs

Soil Fertility and Radicular System Depth of Sand Coastal Plain Forest

Science.gov (United States)

Casagrande, José Carlos; Akemi Sato, Claudia; Reis-Duarte, Rose Mary; Soares, Marcio Roberto; Sérgio Galvão Bueno, Mário

2010-05-01

The sand coastal plain vegetation (Restinga Forest) is a type of ecosystem associated with the Atlantic Forest constituted of mosaics, which occur in areas of great ecological diversity. This vegetation is currently assigned as edaphic communities. In this study we present data on soil fertility in different vegetation physiognomies to discuss on abiotic factors related to Restinga Forest stability and recovery potential. This work was carried out in several points of Restinga Forest in the litoral coast of the state of São Paulo, namely: State Park of the Serra do Mar, Picinguaba, in the city of Ubatuba (23°20' e 23°22' S / 44°48' e 44°52' W); State Park of Anchieta Island, in the city of Ubatuba (45°02' e 45°05' W / 23°31' e 23° 45' S); Restinga Forest in the residential joint ownership Riviera of São Lourenço, in the city of Bertioga (46°08' W e 23°51' S); Ecological Station Juréia-Itatins, Ecological Station of Chauas , in the city of Iguape (24°45' S e 47°33' W) and State Park of Cardoso Island, Pereirinha Restinga Forest, in the city of Cananéia (25°03'05" e 25°18'18" S / 47°53'48" e 48° 05'42" W), Brazil. Sampling was carried out as follows in every area above mentioned. One sample was made of 15 subsamples of each area collected in each depth (one in 0 - 5, 5 - 10, 10 - 15, 15 - 20, and another in 0 - 20, 20 - 40, 40 and 60 cm). Soil characteristics analyzed were pH, P, Na, K, Ca, Mg, S, H + Al, Al, B, Cu, Fe, Mn, Zn contents and base saturation, cation exchange capacity and aluminum saturation. All areas investigated showed very low contents of phosphorous, calcium and magnesium. The base saturation, less than 10, was low due to low amounts of Na, K, Ca and Mg, indicating low nutritional reserve into the soil. The nutritional reserve is present primarily in a depth of 15 cm, although mainly in the vegetable biomass. The level of calcium and magnesium were mainly low in the subsurface soil layer, associate with high concentration of

Oil sands to the rescue: oil sand microbial communities can degrade recalcitrant alkyl phenyl alkanoic acids

Energy Technology Data Exchange (ETDEWEB)

Whitby, Corinne [University of Essex (Canada)], email: cwhitby@essex.ac.uk

2011-07-01

Almost half of all global oil reserves are found as biodegraded heavy oils found in vast tar sand deposits located in North and South America and these account for 47% of Canadian oil production. Oil sand extraction generates large amounts of toxic waste water, known as oil sand process waters (OSPW), that are stored in large tailing ponds that contain toxic compounds like naphthenic acids (NAs). The presence of NAs creates problems like toxicity, corrosion, and the formation of calcium napthenate deposits which block pipelines and other infrastructure and need to be removed. This paper presents oil sand microbial communities that can degrade these NAs. The approach is to apply new aliphatic and aromatic NAs as substrates to supplement and identify NA degrading microbes and also to identify the metabolites produced and explain NA degradation pathways and the functional genes involved. The chemistry and the processes involved are explained. From the results, it is suggested that pure cultures of P. putida KT2440 be used against NAs.

Next-Generation Sequencing Assessment of Eukaryotic Diversity in Oil Sands Tailings Ponds Sediments and Surface Water.

Science.gov (United States)

Aguilar, Maria; Richardson, Elisabeth; Tan, BoonFei; Walker, Giselle; Dunfield, Peter F; Bass, David; Nesbø, Camilla; Foght, Julia; Dacks, Joel B

2016-11-01

Tailings ponds in the Athabasca oil sands (Canada) contain fluid wastes, generated by the extraction of bitumen from oil sands ores. Although the autochthonous prokaryotic communities have been relatively well characterized, almost nothing is known about microbial eukaryotes living in the anoxic soft sediments of tailings ponds or in the thin oxic layer of water that covers them. We carried out the first next-generation sequencing study of microbial eukaryotic diversity in oil sands tailings ponds. In metagenomes prepared from tailings sediment and surface water, we detected very low numbers of sequences encoding eukaryotic small subunit ribosomal RNA representing seven major taxonomic groups of protists. We also produced and analysed three amplicon-based 18S rRNA libraries prepared from sediment samples. These revealed a more diverse set of taxa, 169 different OTUs encompassing up to eleven higher order groups of eukaryotes, according to detailed classification using homology searching and phylogenetic methods. The 10 most abundant OTUs accounted for > 90% of the total of reads, vs. large numbers of rare OTUs (< 1% abundance). Despite the anoxic and hydrocarbon-enriched nature of the environment, the tailings ponds harbour complex communities of microbial eukaryotes indicating that these organisms should be taken into account when studying the microbiology of the oil sands. © 2016 The Author(s) Journal of Eukaryotic Microbiology © 2016 International Society of Protistologists.

[Soil moisture variation under different water and fertilization managements in apple orchard of Weibei dryland, China].

Science.gov (United States)

Zhao, Zhi Yuan; Zheng, Wei; Liu, Jie; Ma, Peng Yi; Li, Zi Yan; Zhai, Bing Nian; Wang, Zhao Hui

2018-04-01

To evaluate the variations of soil moisture under different water and fertilizer treatments in apple orchard in the Weibei dryland, a field experiment was carried out in 2013-2016 at Tianjiawa Village, Baishui County, Shaanxi Province. There were three treatments, i.e., farmers traditional model (only addition of NPK chemical fertilizer, FM), extension model (swine manure and NPK chemical fertilizer combined with black plastic film in tree row space, EM), and optimized model (swine manure and NPK chemical fertilizer combined with black plastic film in tree row space and planting rape in the inter-row of apple trees, OM). The results showed that OM treatment significantly increased soil water storage capacity in 0-200 cm soil layer. Water content of 0-100 cm soil layer was increased by 5.6% and 15.3% in the dry season compared with FM and EM treatment, respectively. Moreover, the soil water relative deficit index of OM was lower than that of EM in 200-300 cm soil layer. The rainfall infiltration in the dry year could reach 300 cm depth under OM. Meanwhile, OM stabilized soil water content and efficiently alleviated the desiccation in deep soil layer. Compared with FM and EM, the 4-year average yield of OM was increased by 36.6% and 22.5%, respectively. In summary, OM could increase water use efficiency through increasing the contents of available soil water and improving the soil water condition in shallow and deep layers, which help alleviate the soil deficit in deep layer and increase yield.

Development of lucerne (Medicago sativa L.) treated with mineral fertilizer and manure at optimal and water deficit conditions.

Science.gov (United States)

Vasileva, V; Kostov, O; Vasilev, E

2006-01-01

A study on the effect of different rates of mineral fertilizer and manure on yield parameters of lucerne under optimal and water deficit conditions was carried out. Leached chernozem soil and lucerne cultivar Victoria were used. The soil was treated with ammonium nitrate and fully matured cattle manure. The plants were grown under optimum moisture content of 80% and 40% of field capacity. The water deficit stress decreased top and root biomass by 11-75% and 3-29% at mineral and organic fertilization, respectively. The applied mineral and organic N strongly depressed nodules development. Both mineral fertilizer and organic manure at dose of 210 mg N kg(-1) soil completely inhibited the appearance of nodules. Next to nitrogen, water deficit stress further inhibited the development of nodules. Nitrogen fertilization increased seed productivity in the two experimental moisture conditions. The water deficit stress decreased seed productivity by 18 to 33% as compared to optimum conditions. The plant treatments with manure were much more resistant to water deficit and recovering ability of plants was faster as compared to treatments with mineral fertilizer. The application of manure stimulates development of drought-stress tolerance in lucerne. However, the results obtained can be considered for the soil type and experimental conditions used.

Total and methyl mercury concentrations in sediment and water of a constructed wetland in the Athabasca Oil Sands Region

International Nuclear Information System (INIS)

Oswald, Claire J.; Carey, Sean K.

2016-01-01

In the Athabasca Oil Sands Region in northeastern Alberta, Canada, oil sands operators are testing the feasibility of peatland construction on the post-mining landscape. In 2009, Syncrude Canada Ltd. began construction of the 52 ha Sandhill Fen pilot watershed, including a 15 ha, hydrologically managed fen peatland built on sand-capped soft oil sands tailings. An integral component of fen reclamation is post-construction monitoring of water quality, including salinity, fluvial carbon, and priority pollutant elements. In this study, the effects of fen reclamation and elevated sulfate levels on mercury (Hg) fate and transport in the constructed system were assessed. Total mercury (THg) and methylmercury (MeHg) concentrations in the fen sediment were lower than in two nearby natural fens, which may be due to the higher mineral content of the Sandhill Fen peat mix and/or a loss of Hg through evasion during the peat harvesting, stockpiling and placement processes. Porewater MeHg concentrations in the Sandhill Fen typically did not exceed 1.0 ng L −1 . The low MeHg concentrations may be a result of elevated porewater sulfate concentrations (mean 346 mg L −1 ) and an increase in sulphide concentrations with depth in the peat, which are known to suppress MeHg production. Total Hg and MeHg concentrations increased during a controlled mid-summer flooding event where the water table rose above the ground surface in most of the fen. The Hg dynamics during this event showed that hydrologic fluctuations in this system exacerbate the release of THg and MeHg downstream. In addition, the elevated SO 4 2− concentrations in the peat porewaters may become a problem with respect to downstream MeHg production once the fen is hydrologically connected to a larger wetland network that is currently being constructed. - Highlights: • A constructed fen peatland in the Athabasca Oil Sands Region was studied. • Total and methyl mercury concentrations in fen sediment and waters

Suitability assessment of grey water quality treated with an upflow-downflow siliceous sand/marble waste filtration system for agricultural and industrial purposes.

Science.gov (United States)

Chaabane, Safa; Riahi, Khalifa; Hamrouni, Hédi; Thayer, Béchir Ben

2017-04-01

The present study examines the suitability assessment of an upflow-downflow siliceous sand/marble waste filtration system for treatment and reuse of grey water collected from bathrooms of the student residential complex at the Higher Institute of Engineering Medjez El Bab (Tunisia). Once the optimization of grey water pre-treatment system has been determined, the filtration system was operated at different hydraulic loading rate and media filter proportions in order to assess the suitability of treated grey water for irrigational purpose according to salinity hazard, sodium hazard, magnesium hazard, permeability index, water infiltration rate, and widely used graphical methods. Suitability of the treated grey water for industrial purpose was evaluated in terms of foaming, corrosion, and scaling. Under optimal operational conditions, results reveals that treated grey water samples with an upflow-downflow siliceous sand/marble waste filtration system may be considered as a good and an excellent water quality suitable for irrigation purpose. However, treated grey water was found not appropriate for industrial purpose due to high concentrations of calcium and sodium that can generate foaming and scaling harm to boilers. These results suggest that treated grey water with an upflow-downflow siliceous sand/marble waste filtration system would support production when used as irrigation water.

The increase of the fertility of soils using the liquid organic fertilizers and fertilizers based on sugar-beet wastes.

Science.gov (United States)

Vyborova, Oxana

2010-05-01

The fertility of soil is a capacity for ensuring plants by water, nutrients, air and capacity for making optimal conditions for growth and development of plants. The result of it is a yield. The main characteristic of fertility of soil is maintenance of humus. The humus is important part of organic matter. The supporting of soil fertility is impossible by traditional methods. The amount of receiving mineral fertilizers in agriculture will not increase in future, because mineral fertilizers are very expensive. The mineral fertilizers don't influence on maintenance of total amount of humus in soil and improve the circulation of nutrients. Every hectare of fields have to receive no less than 8-10 tons of organic fertilizers, therefore we will have self-supporting balance of humus and the fertility of soils will be increasing. Consequently we are looking for new types of organic materials and we include them in modern agro technologies. One of them is an organomineral fertilizer (lignitic materials). The humic chemicals in the form of lignitic materials of natrium, potassium and ammonium are permitted for using them in agriculture at the beginning of 1984. The Department of agriculture in Russian Federation considered the problem of using humic chemicals and made a decision to use them on the fields of our country, because the lignitic materials can restore the fertility of our fields. The lignitic materials increase the amount of spore-forming bacteria, mold fungi and actinomycete. Therefore the organic decomposition occurs more strongly, the processes of humification increase the speed and the amount of humus rises in the soil. The new forming humus has a high biological activity and it improves chemical and physical soil properties. The addition of lignitic materials in soil activates different groups of microorganisms, which influence on mobilization of nutrients and transformation from potential to effective fertility. The inclusion of humic fertilizers improves

Morphophysiology of guava under saline water irrigation and nitrogen fertilization

Directory of Open Access Journals (Sweden)

Idelfonso L. Bezerra

Full Text Available ABSTRACT The aim of this study was to evaluate the growth of grafted guava cv. ‘Paluma’ subjected to different concentrations of salts in irrigation water and nitrogen (N fertilization. The plants were transplanted to 150 L lysimeters and under field conditions at the Science and Agri-food Technology Center of the Federal University of Campina Grande, in the municipality of Pombal - PB. The experiment was conducted in randomized block design in a 5 x 4 factorial scheme, with three replicates, and the treatments corresponded to five levels of electrical conductivity of irrigation water - ECw (0.3; 1.1; 1.9; 2.7 and 3.5 dS m-1 and four N doses (70, 100, 130 and 160% of the N dose recommended for the crop. The doses equivalent to 100% corresponded to 541.1 mg of N dm-3 of soil. Irrigation water salinity above 0.3 dS m-1 negatively affects the number of leaves, leaf area, stem diameter, dry phytomass of leaves, branches and shoots . A significant interaction between irrigation water salinity and N fertilization was observed only for the number of leaves and leaf area at 120 days after transplanting. N dose above 70% of the recommendation (378.7 mg N dm-3 soil did not mitigate the deleterious effects caused by salt stress on plant growth.

Compromised development and survival in amphibians in reclaimed wetlands' water containing oil sands process-affected material

International Nuclear Information System (INIS)

Smits, J.; Schock, D.

2010-01-01

When closing a mine, operators must comply with government regulations to ensure that the sites are ecologically sustainable to support endemic flora and fauna. Creating wetlands in order to age and detoxify oil sands process-affected materials (OSPM) is a common reclamation strategy. In this study, amphibians indigenous to the boreal forest ecosystem were examined to determine if they can complete their lifecycle in water from reclaimed wetlands. Wood frog (Lithobates sylvaticus) eggs were collected from a natural pond 60 km south of an oil sand mining site. Tadpoles were raised in 1 of 6 water treatments refreshed every two days. The 2 reference water treatments included aged tap water and water from natural wetlands. The remaining 4 water treatments were from research wetlands on Syncrude and Suncor lease sites. Of the 120 tadpoles raised per water treatment, there was no significant difference in growth, development, or survival rates between the aged tap water and reference wetland water, but the fastest growth, development, and highest survival rates occurred in the two reference groups. There was a pronounced difference among the 4 treatment groups from Suncor and Syncrude reclamation sites. Survival was high in 3 of the water treatments from Syncrude and Suncor sites, but development rates were considerably reduced. Tadpoles that do not metamorphose before winter do not survive. It was therefore concluded that delayed development in tadpoles poses a serious risk to population stability in OSPM-containing wetlands.

Geochemical behavior and dissolved species control in acid sand pit lakes, Sepetiba sedimentary basin, Rio de Janeiro, SE - Brazil

Science.gov (United States)

Marques, Eduardo D.; Sella, Sílvia M.; Bidone, Edison D.; Silva-Filho, Emmanoel V.

2010-12-01

This work shows the influence of pluvial waters on dissolved components and mineral equilibrium of four sand pit lakes, located in the Sepetiba sedimentary basin, SE Brazil. The sand mining activities promote sediment oxidation, lowering pH and increasing SO 4 contents. The relatively high acidity of these waters, similar to ore pit lakes environment and associated acid mine drainage, increases weathering rate, especially of silicate minerals, which produces high Al concentrations, the limiting factor for fish aquaculture. During the dry season, basic cations (Ca, Mg, K and Na), SiO 2 and Al show their higher values due to evapoconcentration and pH are buffered. In the beginning of the wet season, the dilution factor by rainwater increases SO 4 and decreases pH values. The aluminum monomeric forms (Al(OH) 2+ and Al(OH) 2+), the most toxic species for aquatic organisms, occur during the dry season, while AlSO 4+ species predominate during the wet season. Gibbsite, allophane, alunite and jurbanite are the reactive mineral phases indicated by PHREEQC modeling. During the dry season, hydroxialuminosilicate allophane is the main phase in equilibrium with the solution, while the sulphate salts alunite and jurbanite predominate in the rainy season due to the increasing of SO 4 values. Gibbsite is also in equilibrium with sand pit lakes waters, pointing out that hydrolysis reaction is a constant process in the system. Comparing to SiO 2, sulphate is the main Al retriever in the pit waters because the most samples (alunite and jurbanite) are in equilibrium with the solution in both seasons. This Al hydrochemical control allied to some precaution, like pH correction and fertilization of these waters, allows the conditions for fishpond culture. Equilibrium of the majority samples with kaolinite (Ca, Mg, Na diagrams) and primary minerals (K diagram) points to moderate weathering rate in sand pit sediments, which cannot be considered for the whole basin due to the anomalous

Effective removal of trace thallium from surface water by nanosized manganese dioxide enhanced quartz sand filtration.

Science.gov (United States)

Huangfu, Xiaoliu; Ma, Chengxue; Ma, Jun; He, Qiang; Yang, Chun; Zhou, Jian; Jiang, Jin; Wang, Yaan

2017-12-01

Thallium (Tl) has drawn wide concern due to its high toxicity even at extremely low concentrations, as well as its tendency for significant accumulation in the human body and other organisms. The need to develop effective strategies for trace Tl removal from drinking water is urgent. In this study, the removal of trace Tl (0.5 μg L -1 ) by conventional quartz sand filtration enhanced by nanosized manganese dioxide (nMnO 2 ) has been investigated using typical surface water obtained from northeast China. The results indicate that nMnO 2 enhanced quartz sand filtration could remove trace Tl(I) and Tl(III) efficiently through the adsorption of Tl onto nMnO 2 added to a water matrix and onto nMnO 2 attached on quartz sand surfaces. Tl(III)-HA complexes might be responsible for higher residual Tl(III) in the effluent compared to residual Tl(I). Competitive Ca 2+ cations inhibit Tl removal to a certain extent because the Ca 2+ ions will occupy the Tl adsorption site on nMnO 2 . Moreover, high concentrations of HA (10 mgTOC L -1 ), which notably complexes with and dissolves nMnO 2 (more than 78%), resulted in higher residual Tl(I) and Tl(III). Tl(III)-HA complexes might also enhance Tl(III) penetration to a certain extent. Additionally, a higher pH level could enhance the removal of trace Tl from surface water. Finally, a slight increase of residual Tl was observed after backwash, followed by the reduction of the Tl concentration in the effluent to a "steady" state again. The knowledge obtained here may provide a potential strategy for drinking water treatment plants threatened by trace Tl. Copyright © 2017. Published by Elsevier Ltd.

The fate of fertilizer nitrogen in winter wheat under different water and nitrogen levels

International Nuclear Information System (INIS)

Li Shijuan; Zhou Dianxi; Lan Linwang

2002-01-01

N uptake and the fate of fertilizer N were studied in the field under different water and nitrogen levels with 15 N technique. Results showed that (1) the total N uptake of economical N treatment under saving irrigation was higher than that under conventional irrigation. Under saving irrigation the total N uptake of conventional N was higher than that of economical N treatment, yet the NHI decreased; (2) compared with saving irrigation, the N loss of conventional irrigation increased and NUE and soil residue decreased. On the same water condition the NUE and soil residue of conventional N treatment was lower than that of economical treatment, and N loss increased; (3) for the same fertilizer amount, the loss of N applied all as basal fertilizer is lower than that of part as basal and part as top-dressing treatment

Impact of Fertilizer N Application on the Grey Water Footprint of Winter Wheat in a NW-European Temperate Climate

Directory of Open Access Journals (Sweden)

Holger Brueck

2016-08-01

Full Text Available Nutrient management is central in water footprint analyses as it exerts strong control over crop yield and potentially contributes to pollution of freshwater, the so-called grey water footprint. In the frame of grey water footprint accounting, two methods are suggested, the constant leaching fraction approach (10% of applied fertilizer N and the N surplus approach. We compared both approaches and expected that the N surplus approach gives lower estimates of N leaching (and fertilizer-induced freshwater pollution when the N surplus is small and higher N leaching estimates when the N surplus is high. We compared N fertilizer application at which the N balance = 0 with the N application at which profit is highest. We further expect pronounced differences in N surplus between farm sites and years, due to yield and soil fertility differences. N response trials were conducted at several locations over three years in Germany. Fertilizer-induced N surplus was calculated from the difference between applied N fertilizer and grain N removal. N fertilizer application at which N balance = 0 (NBal = 0 was lower than economic optimum N application rates (NEcon. N surplus at NEcon was linearly correlated with the additional N applied. Pooled over years and sites the median N surplus was 39 kg N ha−1. Differences between sites rather than between years dominated variation in fertilizer-induced N surplus. Estimated N leaching at NEcon was on average 9% of applied fertilizer N. The product water footprint was on average 180 m3 per ton of grain, but differences between sites were substantial with values varying between 0 and >400 m3 per ton. Yield and protein contents were lower at NBal = 0 compared to NEcon indicating a trade-off between freshwater protection, yield, wheat grain quality and economic optimum N application. Site-specific fertilizer strategies which consider soil type, crop development, annual field water balance, in-season nutrient dynamics and

Manganese Coated Sand for Copper (II Removal from Water in Batch Mode

Directory of Open Access Journals (Sweden)

Nidal Hilal

2013-09-01

Full Text Available Removal of heavy metals, such as copper ions, from water is important to protect human health and the environment. In this study, manganese coated sand (MCS was used as an adsorbent to remove copper ions in a batch system. Equilibrium data were determined at a temperature of 25.6 °C and the Langmuir model was used to describe the experimental data. Mn-coating improved the removal of copper ions by 70% as compared to uncoated sand. Based on a kinetics study, the adsorption of copper ions on MCS was found to occur through a chemisorption process and the pseudo-second-order model was found to fit the kinetics experimental data well. Due to particle interactions, the equilibrium uptake was reduced as the ratio of sand to volume of solution increased. pH affected the removal of copper ions with lowest uptakes found at pH 3 and pHs >7, whilst at pHs in the range of 4 to 7, the uptake was highest and almost constant at the value of 0.0179 mg/g ± 4%. This study has also revealed that copper ions removal was dissolved oxygen (DO dependent with the highest removal occurring at ambient DO concentration, which suggests that DO should be carefully studied when dealing with copper ions adsorption.

Sustainable smallholder intensification through improved water management requires adjusted fertilizer recommendation

Science.gov (United States)

Gedfew, Muluye; Schmitter, Petra; Nakawuka, Prossie; Tilahun, Seifu A.; Steenhuis, Tammo; Langan, Simon

2017-04-01

found for pepper. The N and K balances were less negative when farmers used organic fertilizers aside from inorganic fertilizers compared to those farmers who only applied Urea and Di-Ammonium Phosphate (DAP). Furthermore, the largest negative nutrient balances were obtained for the water management leading to the highest crop and water productivity (i.e. CWR). Hence, introducing sustainable water management practices in irrigation requires associated fertilizer recommendations to compensate for the increased yields obtained, avoiding land degradation in the long term.

Bituminous sands : tax issues

International Nuclear Information System (INIS)

Patel, B.

2004-01-01

This paper examined some of the tax issues associated with the production of bitumen or synthetic crude oil from oil sands. The oil sands deposits in Alberta are gaining more attention as the supplies of conventional oil in Canada decline. The oil sands reserves located in the Athabasca, Cold Lake and Peace River areas contain about 2.5 trillion barrels of highly viscous hydrocarbons called bitumen, of which nearly 315 billion barrels are recoverable with current technology. The extraction method varies for each geographic area, and even within zones and reservoirs. The two most common extraction methods are surface mining and in-situ extraction such as cyclic steam stimulation (CSS); low pressure steam flood; pressure cycle steam drive; steam assisted gravity drainage (SAGD); hot water flooding; and, fire flood. This paper also discussed the following general tax issues: bituminous sands definition; bituminous sands leases and Canadian development expense versus Canadian oil and gas property expense (COGPE); Canadian exploration expense (CEE) for surface mining versus in-situ methods; additional capital cost allowance; and, scientific research and experimental development (SR and ED). 15 refs

Experimental and numerical study on thermal conductivity of partially saturated unconsolidated sands

Science.gov (United States)

Lee, Youngmin; Keehm, Youngseuk; Kim, Seong-Kyun; Shin, Sang Ho

2016-04-01

A class of problems in heat flow applications requires an understanding of how water saturation affects thermal conductivity in the shallow subsurface. We conducted a series of experiments using a sand box to evaluate thermal conductivity (TC) of partially saturated unconsolidated sands under varying water saturation (Sw). We first saturated sands fully with water and varied water saturation by drainage through the bottom of the sand box. Five water-content sensors were integrated vertically into the sand box to monitor water saturation changes and a needle probe was embedded to measure thermal conductivity of partially saturated sands. The experimental result showed that thermal conductivity decreases from 2.5 W/mK for fully saturated sands to 0.7 W/mK when water saturation is 5%. We found that the decreasing trend is quite non-linear: highly sensitive at very high and low water saturations. However, the boundary effects on the top and the bottom of the sand box seemed to be responsible for this high nonlinearity. We also found that the determination of water saturation is quite important: the saturation by averaging values from all five sensors and that from the sensor at the center position, showed quite different trends in the TC-Sw domain. In parallel, we conducted a pore-scale numerical modeling, which consists of the steady-state two-phase Lattice-Boltzmann simulator and FEM thermal conduction simulator on digital pore geometry of sand aggregation. The simulation results showed a monotonous decreasing trend, and are reasonably well matched with experimental data when using average water saturations. We concluded that thermal conductivity would decrease smoothly as water saturation decreases if we can exclude boundary effects. However, in dynamic conditions, i.e. imbibition or drainage, the thermal conductivity might show hysteresis, which can be investigated with pore-scale numerical modeling with unsteady-state two-phase flow simulators in our future work.

Modelling the removal of p-TSA (para-toluenesulfonamide) during rapid sand filtration used for drinking water treatment.

Science.gov (United States)

Meffe, Raffaella; Kohfahl, Claus; Holzbecher, Ekkehard; Massmann, Gudrun; Richter, Doreen; Dünnbier, Uwe; Pekdeger, Asaf

2010-01-01

A finite element model was set-up to determine degradation rate constants for p-TSA during rapid sand filtration (RSF). Data used for the model originated from a column experiment carried out in the filter hall of a drinking water treatment plant in Berlin (Germany). Aerated abstracted groundwater was passed through a 1.6m long column-shaped experimental sand filter applying infiltration rates from 2 to 6mh(-1). Model results were fitted to measured profiles and breakthrough curves of p-TSA for different infiltration rates using both first-order reaction kinetics and Michaelis-Menten kinetics. Both approaches showed that degradation rates varied both in space and time. Higher degradation rates were observed in the upper part of the column, probably related to higher microbial activity in this zone. Measured and simulated breakthrough curves revealed an adaption phase with lower degradation rates after infiltration rates were changed, followed by an adapted phase with more elevated degradation rates. Irrespective of the mathematical approach and the infiltration rate, degradation rates were very high, probably owing to the fact that filter sands have been in operation for decades, receiving high p-TSA concentrations with the raw water.

[Preliminary Study of Lonicera hypoglauca on Germination Conditions of Sand Culture Seeds and Sterilization Method of Sand Culture Seedling Sterilization].

Science.gov (United States)

Tan, Mu-xiu; Zeng, Wen-wen; Wei, Peng-xiao; Mo, Qiao-cheng; Pu, Zu-ning; Cen, Xiu-fen; Shi, Feng-hua

2015-05-01

To explore the germination conditions of Lonicera hypoglauca sand culture seeds and the effects of sand culture seedlings sterilization. 0.1% HgCl2 with different sterilization time, different illumination time and temperature culture condition were adopted to study the germination conditions of sand culture seeds. Different sterilization treatments and different hardening-seedling days were used to test the sterilization effect of sand culture seedlings. The sterilization effect of the combination of 75% ethanol 30 s + 0.1% HgCl2 5 min on Lonicera hypoglauca seeds was the optimum,with the average pollution rate of 15.56%, and the average germination rate reached 51.11%. The combination of varied temperature-room temperature under light for 12 h/d was the best, with the average germination rate peaked at 75.49%, and the average germination potential reached 68.36%. The treatment of detergent liquor scrub-tap water wash on the part above the hypocotyl, which was sand cultured under the opening condition and had no root, showed the best sterilization effect, with the average pollution rate was zero, and the average survival rate peaked at 100.00%. The sterilization effect of sand culture seedlings, which was disinfected after cleaning by detergent liquor scrub-tap water wash after hardening-seeding for 30 days, was the best, with the average pollution rate of 50.00%, and the average survival rate of 100.00%. The best sterilization effect is the combination of 75% ethanol 30 s + 0.1% HgCl2 5 min; Lighting for 12 h/d of varied temperature-room temperature is regarded as the optimum culture condition. The treatment of detergent liquor scrub-tap water wash treatment on the part above the hypocotyl,which is sand cultured under the opening condition and had no root, shows the best sterilization effect. For the sand culture seedlings, before inoculated in subculture medium, should be hardening-seedling for some days and sterilized after detergent liquor scrub-tap water wash.

Effect of pore water pressure on P-wave velocity in water-filled sands with partial air saturation; Fukanzen howa jotai no suna shiryo wo denpasuru P ha sokudo ni oyobosu kangeki suiatsu no eikyo

Energy Technology Data Exchange (ETDEWEB)

Kanema, T [Chishitsu-Keisoku Co. Ltd., Tokyo (Japan)

1997-10-22

With an objective to elucidate change in velocity of elastic waves in association with water pressure increase in a sand bed below the groundwater level in a shallow portion of the ground, a measurement experiment was carried out on P-wave velocity in sand samples with partial air saturation. The experiment has used fine sand having an equivalent coefficient of 2.40, a soil particle density of 2.68 g/cm {sup 3} or 60%, and a grain size of 0.36 mm. Inside the water-filled sand sample, two accelerometers were embedded 20 cm apart from each other as vibration receivers. An electromagnetic hammer for P-wave was used as the vibration source. In the experiment, measurement was carried out on the P-wave velocity in association with increase in pore water pressure by applying water pressure afresh to the water-filled sample. As a result of the experiment, the following matters were disclosed: the P-wave velocity increases as the pore water pressure was increased, and a phenomenon was recognized that the dominant frequency changes into high frequency; the degree of increase in the P-wave velocity varies depending on initial saturation of the sample; and bubbles in the pore fluid have their volume decreased due to compression resulted from increased pore water pressure and dissolution of air into the pore water. 6 refs., 11 figs.

Policy Analysis of Water Availability and Use Issues for Domestic Oil Shale and Oil Sands Development

Energy Technology Data Exchange (ETDEWEB)

Ruple, John [Univ. of Utah, Salt Lake City, UT (United States); Keiter, Robert [Univ. of Utah, Salt Lake City, UT (United States)

2010-03-01

Oil shale and oil sands resources located within the intermountain west represent a vast, and as of yet, commercially untapped source of energy. Development will require water, and demand for scarce water resources stands at the front of a long list of barriers to commercialization. Water requirements and the consequences of commercial development will depend on the number, size, and location of facilities, as well as the technologies employed to develop these unconventional fuels. While the details remain unclear, the implication is not – unconventional fuel development will increase demand for water in an arid region where demand for water often exceeds supply. Water demands in excess of supplies have long been the norm in the west, and for more than a century water has been apportioned on a first-come, first-served basis. Unconventional fuel developers who have not already secured water rights stand at the back of a long line and will need to obtain water from willing water purveyors. However, uncertainty regarding the nature and extent of some senior water claims combine with indeterminate interstate river management to cast a cloud over water resource allocation and management. Quantitative and qualitative water requirements associated with Endangered Species protection also stand as barriers to significant water development, and complex water quality regulations will apply to unconventional fuel development. Legal and political decisions can give shape to an indeterminate landscape. Settlement of Northern Ute reserved rights claims would help clarify the worth of existing water rights and viability of alternative sources of supply. Interstate apportionment of the White River would go a long way towards resolving water availability in downstream Utah. And energy policy clarification will help determine the role oil shale and oil sands will play in our nation’s future.

Studeis on the immobilization of water soluble phosphatic fertilizer in some soils with 32P

International Nuclear Information System (INIS)

Zhang Yumei; Li Rensheng; Xu Xinyu

1985-01-01

Using superphosphate lablled with 32 P, we studied immobilization of water-soluble phosphatic fertilizer on 12 typies of soil. The experimental result showed that major factors to govern immobilization of water-soluble phosphatic fertilizer are: quickly availible Fe that showed positive correlation with the immobilization when it was 4.64-65.72 ppm; and pH that showed negative correlation with the immobilization when it was between 5.35 and 8.88. CaCO 3 and organic matter showed a great effect on the immobilization though there wasn't obvious correlation among them

Modelling offshore sand wave evolution

NARCIS (Netherlands)

Nemeth, Attila; Hulscher, Suzanne J.M.H.; van Damme, Rudolf M.J.

2007-01-01

We present a two-dimensional vertical (2DV) flow and morphological numerical model describing the behaviour of offshore sand waves. The model contains the 2DV shallow water equations, with a free water surface and a general bed load formula. The water movement is coupled to the sediment transport

Analysis of the environmental control technology for tar sand development

Energy Technology Data Exchange (ETDEWEB)

de Nevers, N.; Glenne, B.; Bryner, C.

1979-06-01

The environmental technology for control of air pollution, water pollution, and for the disposal, stabilization, and vegetation of the waste tar sand were thoroughly investigated. Although some difficulties may be encountered in any of these undertakings, it seems clear that the air and water pollution problems can be solved to meet any applicable standard. Currently there are two large-scale plants producing liquid fuels from tar sands in Alberta, Canada which use similar technology involving surface mining, hot water extraction, and surface disposal of waste sand. These projects all meet the Canadian environmental control regulations in force at the time they began. The largest US deposits of tar sands are much smaller than the Canadian; 95 percent are located in the state of Utah. Their economics do not appear as attractive as the Canadian deposits. The environmental control costs are not large enough to make an otherwise economic project uneconomic. The most serious environmental conflict likely to occur over the recovery of liquid fuels from the US deposits of tar sands is that caused by the proximity of the deposits to national parks, national monuments, and a national recreation area in Utah. These areas have very stringent air pollution requirements; and even if the air pollution control requirements can be met, there may still be adequate opposition to large-scale mining ventures in these areas to prevent their commercial exploitation. Another environmental constraint may be water rights availability.Essentially all of the water running in the Colorado river basin is now legally allocated. Barring new interpretations of the legality of water rights purchase, Utah tar sands developments should be able to obtain water by purchasing existing irrigation water rights.

Geotechnical properties of crude oil contaminated sand

International Nuclear Information System (INIS)

Puri, V.K.; Das, B.M.; Cook, E.E.; Shin, E.C.

1994-01-01

Contamination of soil due to an oil spill influences its subsequent engineering behavior. An investigation was conducted to study the effect of crude oil contamination on compaction characteristics, shear strength, one-dimensional compression, and coefficient of permeability. Water permeability was also determined by using commercial grade motor oils as contaminants. The test results indicate that the compaction characteristics are influenced by oil contamination. The angle of internal friction of sand (based on total stress condition) decreases due to presence of oil within the pore spaces in sand. One dimensional compression characteristics of sand are significantly influenced by oil contamination resulting in a decrease in the value of constrained modulus with increase in the degree of oil contamination compared to the case of dry sand. Water permeability was observed to be a function of the initial viscosity and the degree of saturation due to the contaminating oil

Afyon-Sandıklı

Indian Academy of Sciences (India)

δ18O and δD isotope ratios of the Sandıklı waters plot along the continental meteoric water line ... and district heating. Several studies on geology, hydrogeology along ..... precipitation; In: Handbook of Environmental Isotope. Geochemistry ...

Effect of Water Stress and Sulfur Fertilizer on Grain Yield, Chlorophyll and Nutrient Status of Black Cumin (Nigella Sativa L.

Directory of Open Access Journals (Sweden)

M. Heidari

2011-04-01

Full Text Available In order to study the effects of water stress and different amounts of sulfur fertilizer on grain yield, nutrient status and chlorophyll content in black cumin (Nigella sativa L. a field experiment as split plot design with three replications was conducted at Ghaen city in 2009. Treatments included three levels of irrigation after 50, 100 and 150 mm evaporation from Class A pan as main plot and four levels of sulfur fertilizer including 0, 75, 150 and 225 kg/ha from bentonite-sulfur source as sub-plot. Statistical analysis of the results showed that water stress has significant effect on grain yield and essential oil of black cumin. At the level of 150 mm evaporation from Class A pan, the grain yield decreased by 22.8% and essential oil by 27.6%. Application of 225 kg/ha sulfur fertilizer increased grain yield up to 7.2%. Water stress and sulfur fertilizer treatments had only significant effect on chlorophyll a content. However, water stress decreased chlorophyll a content, but sulfur fertilizer application up to 225 kg/ha increased the content of chlorophyll a. In this study, water stress decreased potassium content in black cumin leaves, but increased the sodium and calcium accumulation. Although application of sulfur fertilizer affected significantly the potassium and magnesium contents in shoots, but did not have significant effect on sodium and calcium contents.

Evaluation of the Effect of Irrigation and Fertilization by Drip Fertigation on Tomato Yield and Water Use Efficiency in Greenhouse

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Wang Xiukang

2016-01-01

Full Text Available The water shortage in China, particularly in Northwest China, is very serious. There is, therefore, great potential for improving the water use efficiency (WUE in agriculture, particularly in areas where the need for water is greatest. A two-season (2012 and 2013 study evaluated the effects of irrigation and fertilizer rate on tomato (Lycopersicum esculentum Mill., cv. “Jinpeng 10” growth, yield, and WUE. The fertilizer treatment significantly influenced plant height and stem diameter at 23 and 20 days after transplanting in 2012 and 2013, respectively. As individual factors, irrigation and fertilizer significantly affected the leaf expansion rate, but irrigation × fertilizer had no statistically significant effect on the leaf growth rate at 23 days after transplanting in 2012. Dry biomass accumulation was significantly influenced by fertilizer in both years, but there was no significant difference in irrigation treatment in 2012. Our study showed that an increased irrigation level increased the fruit yield of tomatoes and decreased the WUE. The fruit yield and WUE increased with the increased fertilizer rate. WUE was more sensitive to irrigation than to fertilization. An irrigation amount of 151 to 208 mm and a fertilizer amount of 454 to 461 kg·ha−1 (nitrogen fertilizer, 213.5–217 kg·ha−1; phosphate fertilizer, 106.7–108 kg·ha−1; and potassium fertilizer, 133.4–135.6 kg·ha−1 were recommended for the drip fertigation of tomatoes in greenhouse.

WATER CONSUMPTION AND WATER USE EFFICIENCY OF CASTOR BEAN PARAGUAÇÚ CULTIVAR SUBMITTED TO NITROGEN FERTILIZATION

OpenAIRE

Lucia Helena Garófalo Chaves; Hans Raj Ghey; Susane Ribeiro

2011-01-01

Although the productivity of castor bean reduces under water deficit it is considered resistant to low precipitation conditions, thus constituting an alternative form of income for the semi-arid. The scarce information about the effect of nitrogen fertilization on water consumption and efficiency of use motivated this study. The study was conducted in a greenhouse located at the Federal University of Campina Grande – Campus I, with plants arranged in a factorial design with three replications...

Design and development of decentralized water and wastewater technologies: a combination of safe wastewater disposal and fertilizer production.

Science.gov (United States)

Fach, S; Fuchs, S

2010-01-01

Modern wastewater treatment plants are often inappropriate for communities in developing countries. Such communities lack the funding, resources and skilled labour required to implement, operate, and maintain these plants. This research was conducted to investigate and establish an appropriate wastewater treatment system for the district of Gunung Kidul, Indonesia. Due to its lack of water during the dry season, this district is considered one of the poorest areas in the nation. First, wastewater was stored in septic tank units for a retention time of 26 days. Anaerobic conditions occurred, resulting in an 80% reduction of initial COD. The retained sludge was well stabilized with great potential, if dewatered, for reuse as fertilizer. Consequently, supernatant was separated for experiments consisting of lab scale aerobic sand filtering unit. Through filtration, further removals of COD (about 30%) and pathogens were achieved. Rich in nitrogen, the resulting effluent could be used for irrigation and soil conditioning. With faecal sludge and also a mixture of septic sludge and food waste, the hydrolysis stage of anaerobic digestion was examined. This paper discusses the laboratory findings in Karlsruhe and the design and implementation of a treatment system in Glompong, Indonesia.

Oil sands and the environment

Energy Technology Data Exchange (ETDEWEB)

Seeley, R. [Shell Canada Ltd., Calgary, AB (Canada). Calgary Research Centre

2004-07-01

Oil sands are a significant resource for Alberta and Canada with continuing growth opportunity. There is a need to ensure sustainable development of the oil sands resources from a social, economic and environmental perspective. The industry has succeeded in terms of proven reserves, technology advancements, reduced operating costs, reliability and market accessibility. Some of the major challenges facing the industry include high capital cost, infrastructure, social services and keeping pace with growth. This presentation outlined the proactive measures that the oil sands industry has taken to manage environmental issues such as sulphur dioxide and nitrogen oxide emissions, greenhouse gases, water management and land reclamation. tabs., figs.

Rainbow trout (Oncorhynchus mykiss) detection, avoidance, and chemosensory effects of oil sands process-affected water.

Science.gov (United States)

Lari, Ebrahim; Pyle, Greg G

2017-06-01

Oil sands process-affected water (OSPW) - a byproduct of the oil sands industry in Northern Alberta, Canada - is currently stored in on-site tailings ponds. The goal of the present study was to investigate the interaction of OSPW with the olfactory system and olfactory-mediated behaviours of fish upon the first encounter with OSPW. The response of rainbow trout (Oncorhynchus mykiss) to different concentrations (0.1, 1, and 10%) of OSPW was studied using a choice maze and electro-olfactography (EOG), respectively. The results of the present study showed that rainbow trout are capable of detecting and avoiding OSPW at a concentration as low as 0.1%. Exposure to 1% OSPW impaired (i.e. reduced sensitivity) the olfactory response of rainbow trout to alarm and food cues within 5 min or less. The results of the present study demonstrated that fish could detect and avoid minute concentrations of OSPW. However, if fish were exposed to OSPW-contaminated water and unable to escape, their olfaction would be impaired. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influence green sand system by core sand additions

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N. Špirutová

2012-01-01

Full Text Available Today, about two thirds of iron alloys casting (especially for graphitizing alloys of iron are produced into green sand systems with usually organically bonded cores. Separation of core sands from the green sand mixture is very difficult, after pouring. The core sand concentration increase due to circulation of green sand mixture in a closed circulation system. Furthermore in some foundries, core sands have been adding to green sand systems as a replacement for new sands. The goal of this contribution is: “How the green sand systems are influenced by core sands?”This effect is considered by determination of selected technological properties and degree of green sand system re-bonding. From the studies, which have been published yet, there is not consistent opinion on influence of core sand dilution on green sand system properties. In order to simulation of the effect of core sands on the technological properties of green sands, there were applied the most common used technologies of cores production, which are based on bonding with phenolic resin. Core sand concentration added to green sand system, was up to 50 %. Influence of core sand dilution on basic properties of green sand systems was determined by evaluation of basic industrial properties: moisture, green compression strength and splitting strength, wet tensile strength, mixture stability against staling and physical-chemistry properties (pH, conductivity, and loss of ignition. Ratio of active betonite by Methylene blue test was also determined.

Experimental perforation of tubing with a hydraulic sand jet

Energy Technology Data Exchange (ETDEWEB)

Semenov, Yu V

1970-01-01

A series of field tests has shown that perforation with a hydraulic sand jet improves the quality of well completion. The sand jet does not crack the cement sheath or the casing, and the perforations are larger and deeper than perforations formed by explosive charges. Fluid circulation during sand jet perforation can safely be stopped for at least 10 min. Water containing a surfactant can be used as a sand carrier. Sand jet perforation allows successful completion of wells cased by 2 tubing strings. Sand jet perforation can be used to clean the borehole well and to remove foreign objects from the well.

The pH Value of Fungicide, Insecticide and Mineral Fertilizer Mixtures Depending on Water Quality

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Dušanka Inđić

2008-01-01

Full Text Available The paper deals with the effect of water quality on the pH value of fungicides, insecticides, mineral fertilizers and their mixtures. The fungicides propineb (Antracol WP-70 and mancozeb (Dithane M-70, insecticides pirimiphos-methyl (Actellic-50 and imidacloprid(Confidor 200-SL, several fertilizers (Ferticare I, Ferticare II, Ferticare III and Wuxal Super and their mixtures were analyzed for pH value under laboratory conditions using a potentiometric pH meter. Measurements were made directly after preparation or mixing with tap and well water and 24 hours later. Tap water exhibited a neutral reaction. A slightly alkaline reaction of well water was mostlikely due to high ammonium content. The suspensions of Antracol WP-70 exhibited slightly alkaline reactions with both water types during 24 hours. The spray liquids of Dithane M-70 mixed with tap or well water had neutral reaction after preparation and slightly alkaline reaction after 24 hours. The emulsions of Actellic-50 showed neutral reaction with both water types, followed by a pH increase in tap water after 24 hours. The solutions of Confidor200-SL had a slightly alkaline reaction after mixing and the pH value increased with both water types after 24 hours. It is therefore recommended to apply these insecticides directly after preparation. Mineral fertilizers considerably reduced pH values of the fungicide and insecticide components in double and triple mixtures, especially Ferticare nutrients which had a moderately acid reaction. Wuxal Super had a neutral reaction with both water types.The mixtures with well water increased pH values, which indicates that water pH does affect the pH value of the mixture. Both individual fertilizers and all mixtures (double and triple with Ferticare had pH values between 2.4 and 6, which allows their active liquids to be stored for 12 to 24 hours. The suspensions (Antracol WP-70, double and triple mixtures, emulsions (Actellic-50 and Actellic-50+Wuxal Super

Predicted water quality of oil sands reclamation wetlands : impact of physical design and hydrology

International Nuclear Information System (INIS)

2006-01-01

Although engineered wetlands can be used as treatment systems in the reclamation of oil sands mines, a variety of factors must be considered to improve the biological functioning of many oil sands reclamation landscapes. Key factors in the control of concentrations of dissolved substances include area, depth, shape, surrounding landscape material and contributing water quality and quantity. Seasonal cycles of precipitation and ice cover also require consideration in the planning of wetlands ecosystems. This paper presented details of a model designed to predict constituent concentrations in planned wetlands based on probable inflow and processes. Input variables consisted of key substances and hydrological factors that may be encountered on reclaimed landscapes. The model was constructed to perform sensitivity analyses of wetlands with respect to total dissolved solids (TDS), major ions, and naphthenic acids concentrations. Inputs and assumptions drawn from previous environmental impact assessments completed for proposed and approved oil sands projects were used. Results suggested that wetlands volume is an important factor in the moderation of peak flows and substance decay. The predictions generated by the model suggested that wetlands size, tailings and sandcap placement schedules may be manipulated to achieve desired wetlands salinities. It was observed that the proportion of the watershed covered by specific land types can affect both initial and future concentrations. Long-term climate change that results in 15 per cent more or less runoff was predicted to have little effect on wetlands concentrations, although concentrations may rise during periodic droughts. It was concluded that site-specific modelling and careful planning is needed to achieve desired water quality for the creation of engineered wetlands. 18 refs., 3 tabs., 3 figs

Quantifying runoff water quality characteristics from nurseries and avocado groves subjected to altered irrigation and fertilizer regimes

Science.gov (United States)

Samant, S. A.; Beighley, R. E.

2007-12-01

In agriculture, improper, excessive or poorly timed irrigation and fertilizer applications can result in increased pollutants in runoff and degraded water quality. Specifically, the cultivation of salt sensitive plants and nurseries require significant irrigation and fertilizer that leads to high nutrient leaching. In southern California, a large producer of Avocados and nursery plant, waterways are often subjected to elevated nutrient concentrations, which stress the aquatic ecosystem. In this research, the specific objectives are to determine optimal irrigation and fertilizer application rates for minimizing nutrient and sediment export from avocado groves and nurseries. Altered irrigation and fertilizer application experiments will be implemented and monitored at the San Diego State University's Santa Margarita Ecological Reserve, which contains a 12 ha avocado grove and newly constructed 0.4 ha nursery. The study will last for twelve months, with runoff from natural rainfall or irrigation sampled and analyzed for nutrient concentrations on a monthly basis. The growth rate, leaf nutrient content and plant yield will also be monitored monthly. The nursery site is divided into eight plots (13.5-m x 13.5-m), with each plot containing 1200 plants consisting of four commonly used landscaping varieties in southern California. The avocado grove of the Hass variety is divided into four 1-ha plots. The experimental plots represent combinations of irrigation and fertilization practices with different methods and rates. In all cases, irrigation is fully automated based on soil moisture. To assess the effectiveness of the altered irrigation and fertilizer strategies, runoff water quality and plant yield will be compared to controlled treatments. This research is intended to provide a better understanding of how irrigation and fertilizer management can be used for the long-term reduction of nutrients in the Santa Margarita Watershed, which in turn will lead to improved

A Improved Seabed Surface Sand Sampling Device

Science.gov (United States)

Luo, X.

2017-12-01

In marine geology research it is necessary to obtain a suf fcient quantity of seabed surface samples, while also en- suring that the samples are in their original state. Currently,there are a number of seabed surface sampling devices available, but we fnd it is very diffcult to obtain sand samples using these devices, particularly when dealing with fne sand. Machine-controlled seabed surface sampling devices are also available, but generally unable to dive into deeper regions of water. To obtain larger quantities of seabed surface sand samples in their original states, many researchers have tried to improve upon sampling devices,but these efforts have generally produced ambiguous results, in our opinion.To resolve this issue, we have designed an improved andhighly effective seabed surface sand sampling device that incorporates the strengths of a variety of sampling devices. It is capable of diving into deepwater to obtain fne sand samples and is also suited for use in streams, rivers, lakes and seas with varying levels of depth (up to 100 m). This device can be used for geological mapping, underwater prospecting, geological engineering and ecological, environmental studies in both marine and terrestrial waters.

Phase behavior of methane hydrate in silica sand

International Nuclear Information System (INIS)

Sun, Shi-Cai; Liu, Chang-Ling; Ye, Yu-Guang; Liu, Yu-Feng

2014-01-01

Highlights: • Hydrate p-T trace in coarse-grained sediment is consistent with that in bulk water. • Fine-grained sediment affects hydrate equilibrium for the depressed water activity. • Hydrate equilibrium in sediment is related to the pore size distribution. • The application of hydrate equilibrium in sediment depends on the actual condition. -- Abstract: Two kinds of silica sand powder with different particle size were used to investigate the phase behavior of methane hydrate bearing sediment. In coarse-grained silica sand, the measured temperature and pressure range was (281.1 to 284.2) K and (5.9 to 7.8) MPa, respectively. In fine-grained silica sand, the measured temperature and pressure range was (281.5 to 289.5) K and (7.3 to 16.0) MPa, respectively. The results show that the effect of coarse-grained silica sand on methane hydrate phase equilibrium can be ignored; however, the effect of fine-grained silica sand on methane hydrate phase equilibrium is significant, which is attributed to the depression of water activity caused by the hydrophilicity and negatively charged characteristic of silica particle as well as the pore capillary pressure. Besides, the analysis of experimental results using the Gibbs–Thomson equation shows that methane hydrate phase equilibrium is related to the pore size distribution of silica sand. Consequently, for the correct application of phase equilibrium data of hydrate bearing sediment, the geological condition and engineering requirement should be taken into consideration in gas production, resource evaluation, etc

Effect of mineral nitrogen fertilization on growth characteristics of lucerne under induced water deficiency stress

International Nuclear Information System (INIS)

Vasileva, V.; Vasilev, E.; Athar, M.

2011-01-01

Utility of lucerne crop fertilization with nitrogen fertilizer has been discussed in literature with controversy. In this study experiment was conducted to determine the effect of mineral nitrogen at the doses of 40, 80, 120 and 160 mg N/kg on some characteristics of lucerne under induced water deficiency stress at the stage of budding in a pot trial. It was found that mineral nitrogen at the doses of 120 and 160 mg N/kg soil increased the productivity of dry top mass by 17 and 23% in conditions of optimum moisture, and by 9% in conditions of water deficiency stress at the dose of 80 mg N/kg soil. Application of mineral nitrogen at the dose of 120 and 160 mg N/kg soil increased the quantity of dry root mass by 43 and 38% for the conditions of optimum moisture, and by 54-56% for conditions of water deficiency stress. Mineral nitrogen fertilizing at the dose of 40 mg N/kg soil had the lowest suppressive effect on the nodulation (11%). The dose of 160 mg N/kg soil was found to be toxic to nodulation. The dose of 80 mg N/kg soil, at which the crop had the lowest sensitivity to water deficiency stress, was optimal for lucerne development. (author)

Habitat selection models for Pacific sand lance (Ammodytes hexapterus) in Prince William Sound, Alaska

Science.gov (United States)

Ostrand, William D.; Gotthardt, Tracey A.; Howlin, Shay; Robards, Martin D.

2005-01-01

We modeled habitat selection by Pacific sand lance (Ammodytes hexapterus) by examining their distribution in relation to water depth, distance to shore, bottom slope, bottom type, distance from sand bottom, and shoreline type. Through both logistic regression and classification tree models, we compared the characteristics of 29 known sand lance locations to 58 randomly selected sites. The best models indicated a strong selection of shallow water by sand lance, with weaker association between sand lance distribution and beach shorelines, sand bottoms, distance to shore, bottom slope, and distance to the nearest sand bottom. We applied an information-theoretic approach to the interpretation of the logistic regression analysis and determined importance values of 0.99, 0.54, 0.52, 0.44, 0.39, and 0.25 for depth, beach shorelines, sand bottom, distance to shore, gradual bottom slope, and distance to the nearest sand bottom, respectively. The classification tree model indicated that sand lance selected shallow-water habitats and remained near sand bottoms when located in habitats with depths between 40 and 60 m. All sand lance locations were at depths lance and the independent variables are discussed.

Silicon fertilization and soil water tensions on rice development and yield

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Jakeline R. de Oliveira

2016-02-01

Full Text Available ABSTRACT The cultivation of upland rice (Oryza sativa in Brazil occurs mainly in the Cerrado, a region with adverse weather conditions. The use of silicon in its cultivation becomes important, since this nutrient provides higher rigidity, lower transpiration and higher resistance to dry spells in rice plants. The objective of the present study was to evaluate the effect of silicon fertilization and soil water tensions on upland rice development and yield in a Cerrado Oxisol. A 5 x 5 fractionated factorial with five soil water tensions (0, 15, 30, 45 and 60 kPa and five silicon doses (0, 120, 240, 480 and 960 mg dm-3 was used, which were distributed in a randomized block design, with four replicates. Plant height, number of tillers, number of panicles, number of grains per panicle, numbers of full and empty grains and percentage of empty grains were evaluated. Silicon fertilization promotes increased tillering in rice plants at the dose of 960 mg dm-3. The numbers of tillers and panicles decreased with the application of silicon up to the doses of 460 and 490 mg dm-3, respectively. The increase in soil water tensions reduced plant height and the number of full grains, and increased the percentage of empty grains of upland rice.

A Numerical Investigation on the Effect of Gas Pressure on the Water Saturation of Compacted Bentonite-Sand Samples

Directory of Open Access Journals (Sweden)

Jiang-Feng Liu

2017-01-01

Full Text Available In deep geological disposal for high-level radioactive waste, the generated gas can potentially affect the sealing ability of bentonite buffers. There is a competition between water and gas: the former provides sealing by swelling bentonite, and the latter attempts to desaturate the bentonite buffer. Thus, this study focused on numerically modelling the coupling effects of water and gas on the water saturation and sealing efficiency of compacted bentonite-sand samples. Different gas pressures were applied to the top surface of an upper sample, whereas the water pressure on the bottom side of the lower sample was maintained at 4 MPa. The results indicated that gas pressure did not significantly affect the saturation of the bentonite-sand sample until 2 MPa. At 2 MPa, the degree of water saturation of the upper sample was close to 1.0. As the gas pressure increased, this influence was more apparent. When the gas pressure was 6 MPa or higher, it was difficult for the upper sample to become fully saturated. Additionally, the lower sample was desaturated due to the high gas pressure. This indicated that gas pressure played an important role in the water saturation process and can affect the sealing efficiency of bentonite-based buffer materials.

Effects-Directed Analysis of Dissolved Organic Compounds in Oil Sands Process-Affected Water.

Science.gov (United States)

Morandi, Garrett D; Wiseman, Steve B; Pereira, Alberto; Mankidy, Rishikesh; Gault, Ian G M; Martin, Jonathan W; Giesy, John P

2015-10-20

Acute toxicity of oil sands process-affected water (OSPW) is caused by its complex mixture of bitumen-derived organics, but the specific chemical classes that are most toxic have not been demonstrated. Here, effects-directed analysis was used to determine the most acutely toxic chemical classes in OSPW collected from the world's first oil sands end-pit lake. Three sequential rounds of fractionation, chemical analysis (ultrahigh resolution mass spectrometry), and acute toxicity testing (96 h fathead minnow embryo lethality and 15 min Microtox bioassay) were conducted. Following primary fractionation, toxicity was primarily attributable to the neutral extractable fraction (F1-NE), containing 27% of original organics mass. In secondary fractionation, F1-NE was subfractionated by alkaline water washing, and toxicity was primarily isolated to the ionizable fraction (F2-NE2), containing 18.5% of the original organic mass. In the final round, chromatographic subfractionation of F2-NE2 resulted in two toxic fractions, with the most potent (F3-NE2a, 11% of original organic mass) containing predominantly naphthenic acids (O2(-)). The less-toxic fraction (F3-NE2b, 8% of original organic mass) contained predominantly nonacid species (O(+), O2(+), SO(+), NO(+)). Evidence supports naphthenic acids as among the most acutely toxic chemical classes in OSPW, but nonacidic species also contribute to acute toxicity of OSPW.

Effect of bioremediation agents on oil biodegradation in medium-fine sand

International Nuclear Information System (INIS)

Croft, B.C.; Swannell, R.P.J.; Grant, A.L.; Lee, K.

1995-01-01

A spill of weathered Arabian light crude oil on an intertidal sand zone was simulated in the laboratory. Respirometry, chemical, and microbiological methods were employed to assess the effectiveness of two bioremediation agents: a slow-release inorganic (Max Bac) and an oleophilic organic fertilizer (Inipol EAP22). Inipol EAP22 stimulated additional CO 2 evolution, and significantly increased both the total chemoheterotrophic population and the number of hydrocarbon-degrading microorganisms. At the end of the experiment, the residual oil extracted from the Inipol-treated sand was significantly more biodegraded, based on the application of the conserved biomarkers (phytane and 17α, 21β hopane), than that removed from the other sand columns, albeit by a relatively small amount. The results suggested that Inipol EAP22 stimulated the chemoheterotrophic and hydrocarbon-degrading microbial population and, after a lag phase, encouraged oil biodegradation in fine sandy sediments subjected to a vertical tidal cycle

Utilization of wheat straw for the preparation of coated controlled-release fertilizer with the function of water retention.

Science.gov (United States)

Xie, Lihua; Liu, Mingzhu; Ni, Boli; Wang, Yanfang

2012-07-18

With the aim of improving fertilizer use efficiency and minimizing the negative impact on the environment, a new coated controlled-release fertilizer with the function of water retention was prepared. A novel low water solubility macromolecular fertilizer, poly(dimethylourea phosphate) (PDUP), was "designed" and formulated from N,N'-dimethylolurea (DMU) and potassium dihydrogen phosphate. Simultaneously, an eco-friendly superabsorbent composite based on wheat straw (WS), acrylic acid (AA), 2-acryloylamino-2-methyl-1-propanesulfonic acid (AMPS), and N-hydroxymethyl acrylamide (NHMAAm) was synthesized and used as the coating to control the release of nutrient. The nitrogen release profile and water retention capacity of the product were also investigated. The degradation of the coating material in soil solution was studied. Meanwhile, the impact of the content of N-hydroxymethyl acrylamide on the degradation extent was examined. The experimental data showed that the product with good water retention and controlled-release capacities, being economical and eco-friendly, could be promising for applications in agriculture and horticulture.

Starch derivative-based superabsorbent with integration of water-retaining and controlled-release fertilizers.

Science.gov (United States)

Zhong, Kang; Lin, Zuan-Tao; Zheng, Xi-Liang; Jiang, Gang-Biao; Fang, Yu-Sheng; Mao, Xiao-Yun; Liao, Zong-Wen

2013-02-15

Phosphate rock (PHR), a traditional fertilizer, is abundant, but is hard to be utilized by plants. To improve the utilization of PHR, and to integrate water-retaining and controlled-release fertilizers, an agricultural superabsorbent polymer based on sulfonated corn starch/poly (acrylic acid) embedding phosphate rock (SCS/PAA/PHR) was prepared. PHR can be suspended and well-dispersed in SCS/PAA by sulfonated corn starch (SCS). PHR and KOH were mixed in acrylic acid solution to provide phosphorus (P) and potassium (K) nutrients, respectively. Impacts on water absorption capacity of the superabsorbent were investigated. The maximum swelling capacity in distilled water or 0.9 wt.% (weight percent) NaCl solution reached 498 g g(-1) and 65 g g(-1) (water/prepared dry superabsorbent) respectively. Moreover, release behaviours of P and K in SCS/PAA/PHR were also investigated. The results showed that SCS/PAA/PHR possessed excellent sustained-release property of plant nutrient, and the SCS/PAA could improve the P release greatly. Besides, the XPS analysis was employed to study the relationship between PHR and superabsorbent polymer. Copyright © 2012 Elsevier Ltd. All rights reserved.

Modeling impacts of water and fertilizer management on ecosystem services from rice rotated crop systems in China

Science.gov (United States)

Chen, Han; Yu, Chaoqing; Li, Changsheng; Huang, Xiao; Zhang, Jie; Yue, Yali; Huang, Guorui

2015-04-01

Sustainable intensification in agriculture has stressed the need for management practices that could increase crop yields while simultaneously reducing environmental impacts. It is well recognized that water and nutrient management hold great promise to address these goals. This study uses the DNDC biogeochemical model to stimulate the impacts of water regime and nitrogen fertilizer management interactions on ecosystem services of rice rotated crop systems in China. County-level optimal nitrogen fertilizer application rates under various water management practices were captured and then multiple scenarios of water and nitrogen fertilizer management were set to more than 1600 counties with rice rotations in China. Results indicate that an national average of 15.7±5.9% (the mean value and standard deviation derive from variability of three water management practices) reduction of nitrogen fertilizer inputs can be achieved without significantly sacrificing rice yields. On a national scale, shallow flooding with optimal N application rates appear most potential to enhance ecosystem services, which led to 10.6% reduction of nitrogen fertilizer inputs, 34.3% decrease of total GHG emissions, 2.8% less of overall N loss (NH3 volatilization, denitrification and N leaching) and a 1.7% increase of rice yields compared to the baseline scenario. Regional GHG emissions mitigation derived from water regime change vary with soil properties and the multiple crop index. Among the main production regions of rice in China, the highest reduction happened in Jiangxu, Yunnan, Guizhou and Hubei (more than 40% reduction) with high SOC, high multiple crop index and low clay fraction. The highest reduction of GHG emissions derived from reducing current N application rate to optimal rate appeared in Zhejiang, Guangdong, Jiangsu where the serious over-application of mineral N exit. It was concluded that process models like DNDC would act an essential tool to identify sustainable agricultural

Effects of Watering and Nitrogen Fertilization on Yield and Water and Nitrogen Use Efficiency of Cropping Oil Sunflower

Directory of Open Access Journals (Sweden)

TAN Jian-xin

2015-10-01

Full Text Available The field experiment with split-plot design was conducted to study the effects of the interaction of water and nitrogen fertilization on the growth and yield of oil sunflower, water and nitrogen use efficiency of cropping oil sunflower. This experiment set three irrigation rate treatments, including high irrigation treatment (5 250 m3·hm-2, middle irrigation treatment (3 750 m3·hm-2, low irrigation treatment (2 250 m3·hm-2, and four nitrogen application rate treatments, covering no nitrogen fertilization treatment (0 kg·hm-2, low nitrogen application treatment (120 kg·hm-2, middle nitrogen application treatment (240 kg·hm-2 and high nitrogen application treatment (360 kg·hm-2. The results showed that the nitrogen absorption and nitrogen use efficiency of cropping oil sunflower increased as the irrigation rate increased. With the nitrogen application rate increased, the yield of cropping oil sunflower was increased when the nitrogen application rate was 0~240 kg·hm-2, but beyond the 240 kg·hm-2, there was no significant increase. With the irrigation rate increased, the water consumption amount of cropping oil sunflower increased all the time, but the water use efficiency increased first, and hen decreased. Besides there was no significant difference between 240 kg·hm-2 and 360 kg·hm-2 treatment. Under our experiment condition, during the cropping oil sunflower growth period, when the irrigation rate was 5 250 m3·hm-2 (high irrigation rate and the nitrogen ertilization was 360 m3·hm-2 (high nitrogen application rate, the yield of cropping oil sunflower was 3 598 kg·hm-2. When the irrigation rate was 3 750 m3·hm-2 (middle irrigation rate and the nitrogen fertilization was 240 m3·hm-2 (middle nitrogen application rate, the yield was 3 518 kg·hm-2, with the yield components similar with the high irrigation rate and high nitrogen application rate treatment. Considering various factors, middle irrigation rate and middle nitrogen

Sorption and desorption of arsenic to ferrihydrite in a sand filter.

Science.gov (United States)

Jessen, Soren; Larsen, Flemming; Koch, Christian Bender; Arvin, Erik

2005-10-15

Elevated arsenic concentrations in drinking water occur in many places around the world. Arsenic is deleterious to humans, and consequently, As water treatment techniques are sought. To optimize arsenic removal, sorption and desorption processes were studied at a drinking water treatment plant with aeration and sand filtration of ferrous iron rich groundwater at Elmevej Water Works, Fensmark, Denmark. Filter sand and pore water were sampled along depth profiles in the filters. The sand was coated with a 100-300 microm thick layer of porous Si-Ca-As-contaning iron oxide (As/Fe = 0.17) with locally some manganese oxide. The iron oxide was identified as a Si-stabilized abiotically formed two-line ferrihydrite with a magnetic hyperfine field of 45.8 T at 5 K. The raw water has an As concentration of 25 microg/L, predominantly as As(II). As the water passes through the filters, As(III) is oxidized to As(V) and the total concentrations drop asymptotically to a approximately 15 microg/L equilibrium concentration. Mn is released to the pore water, indicating the existence of reactive manganese oxides within the oxide coating, which probably play a role for the rapid As(III) oxidation. The As removal in the sand filters appears controlled by sorption equilibrium onto the ferrihydrite. By addition of ferrous chloride (3.65 mg of Fe(II)/L) to the water stream between two serially connected filters, a 3 microg/L As concentration is created in the water that infiltrates into the second sand filter. However, as water flow is reestablished through the second filter, As desorbs from the ferrihydrite and increases until the 15 microg/L equilibrium concentration. Sequential chemical extractions and geometrical estimates of the fraction of surface-associated As suggest that up to 40% of the total As can be remobilized in response to changes in the water chemistry in the sand filter.

Evaluating the Metal Tolerance Capacity of Microbial Communities Isolated from Alberta Oil Sands Process Water.

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Mathew L Frankel

Full Text Available Anthropogenic activities have resulted in the intensified use of water resources. For example, open pit bitumen extraction by Canada's oil sands operations uses an estimated volume of three barrels of water for every barrel of oil produced. The waste tailings-oil sands process water (OSPW-are stored in holding ponds, and present an environmental concern as they are comprised of residual hydrocarbons and metals. Following the hypothesis that endogenous OSPW microbial communities have an enhanced tolerance to heavy metals, we tested the capacity of planktonic and biofilm populations from OSPW to withstand metal ion challenges, using Cupriavidus metallidurans, a known metal-resistant organism, for comparison. The toxicity of the metals toward biofilm and planktonic bacterial populations was determined by measuring the minimum biofilm inhibitory concentrations (MBICs and planktonic minimum inhibitory concentrations (MICs using the MBEC ™ assay. We observed that the OSPW community and C. metallidurans had similar tolerances to 22 different metals. While thiophillic elements (Te, Ag, Cd, Ni were found to be most toxic, the OSPW consortia demonstrated higher tolerance to metals reported in tailings ponds (Al, Fe, Mo, Pb. Metal toxicity correlated with a number of physicochemical characteristics of the metals. Parameters reflecting metal-ligand affinities showed fewer and weaker correlations for the community compared to C. metallidurans, suggesting that the OSPW consortia may have developed tolerance mechanisms toward metals present in their environment.

Responses of woody species to spatial and temporal ground water changes in coastal sand dune systems

Science.gov (United States)

Máguas, C.; Rascher, K. G.; Martins-Loução, A.; Carvalho, P.; Pinho, P.; Ramos, M.; Correia, O.; Werner, C.

2011-12-01

In spite of the relative importance of groundwater in costal dune systems, studies concerning the responses of vegetation to ground water (GW) availability variations, particularly in Mediterranean regions, are scarce. Thus, the main purpose of this study is to compare the responses of co-occurring species possessing different functional traits, to changes in GW levels (i.e. the lowering of GW levels) in a sand dune ecosystem. For that, five sites were established within a 1 km2 area in a meso-mediterranean sand dune ecosystem dominated by a Pinus pinaster forest. Due to natural topographic variability and anthropogenic GW exploitation, substantial variability in depth to GW between sites was found. Under these conditions it was possible to identify the degree of usage and dependence on GW of different plant species (two deep-rooted trees, a drought adapted shrub, a phreatophyte and a non-native woody invader) and how GW dependence varied seasonally and between the heterogeneous sites. Results indicated that the plant species had differential responses to changes in GW depth according to specific functional traits (i.e. rooting depth, leaf morphology, and water use strategy). Species comparison revealed that variability in pre-dawn water potential (Ψpre) and bulk leaf δ13C was related to site differences in GW use in the deep-rooted (Pinus pinaster, Myrica faya) and phreatophyte (Salix repens) species. However, such variation was more evident during spring than during summer drought. The exotic invader, Acacia longifolia, which does not possess a very deep root system, presented the largest seasonal variability in Ψpre and bulk leaf δ13C. In contrast, the response of Corema album, an endemic understory drought-adapted shrub, seemed to be independent of water availability across seasons and sites. Thus, the susceptibility to lowering of GW due to anthropogenic exploitation, in plant species from sand dunes, is variable, being particularly relevant for deep

Organic fertilizer application increases the soil respiration and net ecosystem carbon dioxide absorption of paddy fields under water-saving irrigation.

Science.gov (United States)

Yang, Shihong; Xiao, Ya Nan; Xu, Junzeng

2018-04-01

Quantifying carbon sequestration in paddy soil is necessary to understand the effect of agricultural practices on carbon cycles. The objective of this study was to assess the effect of organic fertilizer addition (MF) on the soil respiration and net ecosystem carbon dioxide (CO 2 ) absorption of paddy fields under water-saving irrigation (CI) in the Taihu Lake Region of China during the 2014 and 2015 rice-growing seasons. Compared with the traditional fertilizer and water management (FC), the joint regulation of CI and MF (CM) significantly increased the rice yields and irrigation water use efficiencies of paddy fields by 4.02~5.08 and 83.54~109.97% (p < 0.05). The effects of organic fertilizer addition on soil respiration and net ecosystem CO 2 absorption rates showed inter-annual differences. CM paddy fields showed a higher soil respiration and net CO 2 absorption rates during some periods of the rice growth stage in the first year and during most periods of the rice growth stage in the second year. These fields also had significantly higher total CO 2 emission through soil respiration (total R soil ) and total net CO 2 absorption compared with FC paddy fields (p < 0.05). The total R soil and net ecosystem CO 2 absorption of CM paddy fields were 67.39~91.55 and 129.41~113.75 mol m -2 , which were 27.66~135.52 and 12.96~31.66% higher than those of FC paddy fields. The interaction between water and fertilizer management had significant effects on total net ecosystem CO 2 absorption. The frequent alternate wet-dry cycles of CI paddy fields increased the soil respiration and reduced the net CO 2 absorption. Organic fertilizer promoted the soil respiration of paddy soil but also increased its net CO 2 absorption and organic carbon content. Therefore, the joint regulation of water-saving irrigation and organic fertilizer is an effective measure for maintaining yield, increasing irrigation water use efficiency, mitigating CO 2 emission, and promoting paddy

Application of a nanofibrous composite membrane to the fertilizer-driven forward osmosis process for irrigation water use.

Science.gov (United States)

An, Hee-Kyung; Lee, Chang-Gu; Park, Seong-Jik

2017-11-01

In this study, we fabricated a nanofibrous composite (NFC) membrane as a substrate to produce forward osmosis (FO) membranes, and we also assessed the use of liquid fertilizer as a draw solution for the FO process in order to produce agricultural irrigation water. Commercial cellulose triacetate (CTA) and thin-film composite (TFC) FO membranes were included in this study. Under FO tests, the NFC, CTA, and TFC membranes achieved initial osmotic water flux values of 35.31, 6.85, and 3.31 L/m 2 ·h and final osmotic water flux values of 12.62, 6.31, and 3.85 L/m 2  h, respectively. The reason for the high osmotic water flux of the NFC membrane is because its nanofiber layer has low tortuosity, high porosity, and a low thickness, resulting in a reduction in the internal concentration polarization phenomenon. When liquid fertilizer was used as the draw solution, the water flux values in the FO experiments for the NFC, CTA, and TFC membranes were 15.54, 5.46, and 2.54 L/m 2  h. Finally, our results revealed that the FO process using liquid fertilizer as a draw solution can be applied to produce agricultural irrigation water from brackish water and the newly fabricated NFC membrane can be applied to the FO process.

Late Pleistocene shallow water sand transported to the slope at IODP Sites U1484 and U1485 off the north coast of Papua New Guinea: how, when and why?

Science.gov (United States)

Mountain, G. S.; Browning, J. V.; Bova, S. C.

2017-12-01

IODP Exp 363 drilled two sites on a gently seaward-dipping terrace 18 and 21 km north of Papua New Guinea, enabling the study of mechanisms that bring shallow water sediment to the deep sea. We expect past changes in sea level and precipitation / fluvial run-off dominated this record, but additional processes may have been important. We examined Hole U1484B (1031 m water depth; 223 m drilled; 99.8% recovered) and detected 339 sharp-based sand layers 0.5 cm or more thick. In contrast to the background hemipelagic nanno-bearing silty clay, sand layers are graded or massive turbidites containing detrital grains, shallow-water benthic foraminifera, shell fragments and/or wood. δ18O values of Globigerinoides ruber tied to the isotopic curve of Lisiecki and Raymo (2004) show the densest concentration of sand layers in the last 310 ka occurred during the cooling trend of MIS stage 6. Stage 2 contains significantly fewer discrete sand beds, even during the coldest part of the LGM. Other times of glacial intensification show a similarly modest correlation to peak sand deposition. Sand layers strongly correlate with high values of magnetic susceptibility (MS) measured on unsplit cores, and when mapped to the MIS time scale, MS increases match times of ice growth / falling sea level more consistently than does the density of sand layers. We attribute this to reworking of discrete sand layers by bioturbation, indicating the need for caution tying the absence of sharp-based sands to times of transgression or low precipitation / fluvial run-off. Packages of especially thick and closely-spaced sharp-based sands match seismic reflections at Site U1484. Tracing these reflections throughout the grid of hi-res MCS site survey profiles reveals the areal distribution and transport path of sand as well as a direct tie to similar sharp-based sands in the more distal Hole U1485A (1145 m water depth; 301 m drilled; 103.8% recovered.) The distribution of sands through time might be

Sulphur output from oil sands : dramatically changing Alberta's sulphur balance

International Nuclear Information System (INIS)

D'Aquin, G.

2008-01-01

This paper discussed sulphur production from Alberta's gas and oil sands industries. While sulfur derived from natural gas production in the province is expected to decline as natural gas reserves diminish, Alberta's oil sands contain high amounts of sulphur. It is not yet known how much sulphur will be produced from the province's oil sands facilities. Alberta had considerable stockpiles of sulphur in the 1970s. By 1980, inventories began to decline. By 1996, output had increased to 7.1 million tonnes. Alberta's sulphur inventory reached 9.7 million tonnes following the collapse of the Soviet Union's government mandated fertilizer industry. In 2006, sulphur supplies in Alberta reached 12 million tonnes. Reduced global output has now lowered sulphur stockpiles. Increases in sulphur prices tend to reduce market demand, and lower prices will not typically change the volume of sulphur produced as a byproduct of oil and gas operations. Bitumen-derived sulphur output is expected to exceed gas-derived sulphur output in the near future. Sulphur from oil sands processing is expected to increase by 5 million tonnes by 2017. Increased sulphur production levels in Alberta will present a significant challenge for all sectors of the hydrocarbon industry. It was concluded that developing a plan for storing, selling or disposing of the sulphur will help to ensure the profitability of oil sands operations

Marine pollution: Let us not forget beach sand

OpenAIRE

Galgani, Francois; Ellerbrake, Katrin; Fries, Elke; Goreux, Chantal

2011-01-01

Background: Assessing the chemical or bacterial contamination in marine waters and sediments is a very common approach to evaluate marine pollution and associated risks. However, toxicity and organic pollution of beach sands have not yet been considered, except in adjacent waters. In the present study, the toxicity and the chemical contamination of natural beach sands collected 20 m from the shoreline at two sites located on the Mediterranean Sea (Marseille and La Marana, Corsica) were studie...

Novel Fabrication of Biodegradable Superabsorbent Microspheres with Diffusion Barrier through Thermo-Chemical Modification and Their Potential Agriculture Applications for Water Holding and Sustained Release of Fertilizer.

Science.gov (United States)

Feng, Diejing; Bai, Bo; Wang, Honglun; Suo, Yourui

2017-07-26

Synergistic utilization of water and fertilizer has vital contribution to the modern production of agriculture. This work reports on a simple and facile strategy to prepare biodegradable yeast/sodium alginate/poly(vinyl alcohol) superabsorbent microspheres with a diffusion barrier merit by thermo-chemical modification route. The integrated performances, including water absorbency, water retention, water evaporation ratio, leaching loss control, sustained-release behaviors, and degradation in soil, were systematically investigated. The results revealed that the modified microspheres were a triumphant water and fertilizer manager to effectively hold water and control the unexpected leakage of fertilizer for sustained release. Therefore, this work provides a promising approach to ameliorate the utilization efficiency of water and fertilizer in potential agriculture applications.

Beach Sand Analysis for Indicators of Microbial Contamination

Science.gov (United States)

Traditional beach monitoring has focused on water quality, with little attention paid to health risks associated with beach sand. Recent research has reported that fecal indicator bacteria, as well as human pathogens can be found in beach sand and may constitute a risk to human h...

Effect of Different Level of Water Stress and Nitrogen Fertilizer on Yield and Yield Components of Barley in Badjgah (Fars province

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ali asghar ghaemi

2016-02-01

Full Text Available Introduction: Barley is very important to feed humans, livestock, medical, industrial uses, especially in fermentation industries. In Iran, barley crop cultivation was nearly 1.4 million hectares withits production of 1.3 million tons in 2003 (2. Barelyis the oldest crops to environmental stresses such as drought and salinity resistance (3.The different barely growth stages with extreme water requirement can benoted in germination stage, stem elongation, heading the production stage, the stage of flowering and seed production. Typically, for spring and autumn barely respectively 3 and 4 to 5 times irrigation is done during the growing season. The barley water requirement over its life is between 4 and 7 thousand cubic meters and 518 liters of water is needed to produce one kilogram of dry matter. Due to limited water resources and low rainfall in Iran, efficient use of water is absolutely essential and the maximum water utilization must be achieved by applying a minimum amount of water in agriculture. One of the ways to increase productivity in agricultural water is deficit irrigation.Deficit irrigation is an optimization strategy for water use efficiency in irrigation.The purpose of this study was to evaluate the simultaneous effect of fertilizer treatments (150, 225 and 75 kg/ ha and water at three different levels (100%, 75% and 50% of crop water requirement at different growth stages on leaf area index, weight fresh and dried herb and plant nitrogen concentration and the effect of irrigation and nitrogen fertilizer on yield, yield components and productivity of water use. Materials and Method: This research was conducted in Shiraz University in fall 2012 to study the effect of interaction of deficit irrigation and nitrogen fertilizer on yield, yield component and water use efficiency and nitrogen concentration in different stages of barley (Bahman species growth. This experiment were evaluated using a randomized complete block design with s

Depth investigation of rapid sand filters for drinking water production reveals strong stratification in nitrification biokinetic behavior

DEFF Research Database (Denmark)

Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

2016-01-01

The biokinetic behavior of NH4 + removal was investigated at different depths of a rapid sand filter treating groundwater for drinking water preparation. Filter materials from the top, middle and bottom layers of a full-scale filter were exposed to various controlled NH4 + loadings in a continuous...

Microbial metabolism alters pore water chemistry and increases consolidation of oil sands tailings.

Science.gov (United States)

Arkell, Nicholas; Kuznetsov, Petr; Kuznetsova, Alsu; Foght, Julia M; Siddique, Tariq

2015-01-01

Tailings produced during bitumen extraction from surface-mined oil sands ores (tar sands) comprise an aqueous suspension of clay particles that remain dispersed for decades in tailings ponds. Slow consolidation of the clays hinders water recovery for reuse and retards volume reduction, thereby increasing the environmental footprint of tailings ponds. We investigated mechanisms of tailings consolidation and revealed that indigenous anaerobic microorganisms altered porewater chemistry by producing CO and CH during metabolism of acetate added as a labile carbon amendment. Entrapped biogenic CO decreased tailings pH, thereby increasing calcium (Ca) and magnesium (Mg) cations and bicarbonate (HCO) concentrations in the porewater through dissolution of carbonate minerals. Soluble ions increased the porewater ionic strength, which, with higher exchangeable Ca and Mg, decreased the diffuse double layer of clays and increased consolidation of tailings compared with unamended tailings in which little microbial activity was observed. These results are relevant to effective tailings pond management strategies. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Numerical simulation of flow and compression of green sand

DEFF Research Database (Denmark)

Hovad, Emil

The focus of the industrial PhD project was concentrated on the production of the sand mold (green sand) which gives the cast component its final geometrical shape. In order to ensure a high quality of the cast component, it is important to control the manufacturing process of the mold itself so...... that it is homogeneous and stable. Therefore gaining a basic understanding of how the flow and deposition of green sand should be characterized and modelled was important, so that it could be used for simulation of the manufacturing process of the sand mold. The flowability of the green sand is important when the sand...... flows down through the hopper filling the chamber with sand during the sand shot. The flowability of green sand is mostly governed by the amount of water and bentonite which both decrease it. The flowability and the internal forces thus control how well you can fill a complex mold geom-etry in which...

Transport of 152Eu colloids in a system of fine sand and water containing humic substances

International Nuclear Information System (INIS)

Klotz, D.

1995-01-01

The migration of 152 Eu in a system of fine sand and water containing humic substances was investigated in a flow column system under realistic conditions. In this system, the trivalent Eu forms colloids with the water. These Eu humates are transported without retardation at recovery rates significantly below 100 per cent. Recovery is more or less a measure of the physical process of filtration of Eu bonded to particulates. In the range of natural filtering rates, the recovery rates decrease with decreasing filtering rate. (orig.) [de

The kinetics of activation and deactivation in the process of water ozonising used for advanced oxidation of the dust waste from moulding sands

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A. Baliński

2009-01-01

Full Text Available Adding coal dust and organic carriers of the lustrous carbon to bentonite-bonded moulding sands in amounts justified by thetechnological regime and the use of cores and protective coatings based on organic compounds create serious threats to the environment.During thermal destruction of the individual components of moulding and core sands, some toxic organic compounds are emitted. They formthe majority of the Hazardous Air Pollutants (HAPs, and include mainly compounds like benzene, toluene, xylene, naphtalene, hexane,acetaldehyde, acrolein, aniline, cresol and cumene, their polycyclic derivatives, phenol, formaldehyde, and other similar matters. In thusformed dust waste, the amount of which constitutes about 20% of all the waste from foundries using traditional moulding and core sands, there are still full-value materials which can undergo total recycling, providing the HAPs are partially or totally removed from them. The article discusses some problems of the advanced oxidation of selected toxic chemical compounds present in bentonite-bonded moulding sands due to the effect of high temperature. The results of the investigations of the kinetics of the process of maximum water saturation with ozone (acting as an oxidiser and of the kinetics of the natural process of ozone decomposition to diatomic oxygen were presented. It has been stated that the maximum time of water saturation with ozone using an OZOMATIC OSC-MODULAR 4HC ozone generator and a 1m3 capacity tank with water is 60 minutes. After 30 minute break in the ozonising process, the ozone concentration in water decreases by 40 to 50%. To obtain maximum ozone concentration in water during the next ozonising cycle, it is necessary to have the ozone-generating device running for the next 30 minutes. The stabilisation of ozone concentration in water takes place only after the third ozonising cycle, when it reaches nearly 80%of the maximum value obtained after the first process cycle

Naphtha evaporation from oil sands tailings ponds

Energy Technology Data Exchange (ETDEWEB)

Kasperski, K.; Munoz, V.; Mikula, R. [Natural Resources Canada, Devon, AB (Canada). CANMET Western Research Centre

2010-07-01

The environmental impacts of volatile organic compounds (VOCs) from oil sands tailings ponds must be considered when evaluating new oil sands mining and extraction operations. Studies have suggested that only 40 percent of the solvent sent to tailings ponds is available to the environment, while the rest is irreversibly trapped. The recovery of hydrocarbons from oil sands froth process water is low. This PowerPoint presentation discussed a method of distinguishing between water and hydrocarbons at low temperatures. Samples were heated to 246 degrees C at 15 degrees C and held for 10 minutes. Heating was then resumed at 750 degrees C and held for 10 minutes in a pyrolysis phase, then cooled and reheated with an oxygen addition. The method demonstrated that the diluent distribution between the solids and water phases is misinterpreted as diluent that will evaporate, and diluent that will not evaporate. The study concluded by suggesting that the definition of recoverable and unrecoverable hydrocarbon should be re-termed as easily recoverable, and difficult to recover. tabs., figs.

Experimental Measurement of Diffusive Extinction Depth and Soil Moisture Gradients in Southwestern Saudi Arabian Dune Sand

KAUST Repository

Mughal, Iqra

2013-05-01

In arid lands, a major contribution to water loss is by soil water evaporation. Desert sand dunes in arid regions are devoid of runoff and have high rates of infiltration. Rainwater is commonly stored within them because of the low permeability soils in the underlying desert pavement. In such cases, moisture is confined in the sand dune below a depth, termed as the “extinction depth”, where it is protected from evaporation during long dry periods. Moreover, desert sand dunes have sparse vegetation, which results in low transpiration losses from the stored water. The water accumulated below the extinction depth of the sand dunes can be utilized for various purposes such as in irrigation to support desert agriculture. In this study, field experiments were conducted in Western Saudi Arabia to monitor the soil moisture gradients and determine the diffusive extinction depth of dune sand. The dune sand was saturated with water and was exposed to natural conditions (evaporation and precipitation). The decline of the water level in the sand column was continuously recorded using transducers and sensors installed at different depths monitored the temporal variation of temperature and moisture content within the sand. The hydrological simulator HYDRUS-1D was used to construct the vertical profiles of soil water content and temperature and the results obtained from HYDRUS-1D were compared to the gradients monitored by the sensors.

A GIS policy approach for assessing the effect of fertilizers on the quality of drinking and irrigation water and wellhead protection zones (Crete, Greece).

Science.gov (United States)

Kourgialas, Nektarios N; Karatzas, George P; Koubouris, Georgios C

2017-03-15

Fertilizers have undoubtedly contributed to the significant increase in yields worldwide and therefore to the considerable improvement of quality of life of man and animals. Today, attention is focussed on the risks imposed by agricultural fertilizers. These effects include the dissolution and transport of excess quantities of fertilizer major- and trace-elements to the groundwater that deteriorate the quality of drinking and irrigation water. In this study, a map for the Fertilizer Water Pollution Index (FWPI) was generated for assessing the impact of agricultural fertilizers on drinking and irrigation water quality. The proposed methodology was applied to one of the most intensively cultivated with tree crops area in Crete (Greece) where potential pollutant loads are derived exclusively from agricultural activities and groundwater is the main water source. In this region of 215 km 2 , groundwater sampling data from 235 wells were collected over a 15-year time period and analyzed for the presence of anionic (ΝΟ -3 , PO -3 4 ) and cationic (K +1 , Fe +2 , Mn +2 , Zn +2 , Cu +2 , B +3 ) fertilizer trace elements. These chemicals are the components of the primary fertilizers used in local tree crop production. Eight factors/maps were considered in order to estimate the spatial distribution of groundwater contamination for each fertilizer element. The eight factors combined were used to generate the Fertilizer Water Pollution Index (FWPI) map indicating the areas with drinking/irrigation water pollution due to the high groundwater contamination caused by excessive fertilizer use. Moreover, by taking into consideration the groundwater flow direction and seepage velocity, the pathway through which groundwater supply become polluted can be predicted. The groundwater quality results show that a small part of the study area, about 8 km 2 (3.72%), is polluted or moderately polluted by the excessive use of fertilizers. Considering that in this area drinking water sources

Study on the Permeability Characteristics of Polyurethane Soil Stabilizer Reinforced Sand

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Jin Liu

2017-01-01

Full Text Available A polymer material of polyurethane soil stabilizer (PSS is used to reinforce the sand. To understand the permeability characteristics of PSS reinforced sand, a series of reinforcement layer form test, single-hole permeability test, and porous permeability test of sand reinforced with PSS have been performed. Reinforcement mechanism is discussed with scanning electron microscope images. The results indicated that the permeability resistance of sand reinforced with polyurethane soil stabilizer is improved through the formation of reinforcement layer on the sand surface. The thickness and complete degree of the reinforcement layer increase with the increasing of curing time and PSS concentration. The water flow rate decreases with the increasing of curing time or PSS concentration. The permeability coefficient decreases with the increasing of curing time and PSS concentration and increases with the increasing of depth in specimen. PSS fills up the voids of sand and adsorbs on the surface of sand particle to reduce or block the flowing channels of water to improve the permeability resistance of sand. The results can be applied as the reference for chemical reinforcement sandy soil engineering, especially for surface protection of embankment, slope, and landfill.

How cuckoldry can decrease the opportunity for sexual selection: Data and theory from a genetic parentage analysis of the sand goby, Pomatoschistus minutus

Science.gov (United States)

Jones, Adam G.; Walker, DeEtte; Kvarnemo, Charlotta; Lindström, Kai; Avise, John C.

2001-01-01

Alternative mating strategies are common in nature and are generally thought to increase the intensity of sexual selection. However, cuckoldry can theoretically decrease the opportunity for sexual selection, particularly in highly polygamous species. We address here the influence of sneaking (fertilization thievery) on the opportunity for sexual selection in the sand goby Pomatoschistus minutus, a marine fish species in which males build and defend nests. Our microsatellite-based analysis of the mating system in a natural sand goby population shows high rates of sneaking and multiple mating by males. Sneaker males had fertilized eggs in ≈50% of the assayed nests, and multiple sneakers sometimes fertilized eggs from a single female. Successful males had received eggs from 2 to 6 females per nest (mean = 3.4). We developed a simple mathematical model showing that sneaking in this polygynous sand goby population almost certainly decreases the opportunity for sexual selection, an outcome that contrasts with the usual effects of cuckoldry in socially monogamous animals. These results highlight a more complex and interesting relationship between cuckoldry rates and the intensity of sexual selection than previously assumed in much of the literature on animal mating systems. PMID:11481481

Effect of manufactured sand on the durability characteristics of concrete

Directory of Open Access Journals (Sweden)

S. S. SARAVANAN

2016-12-01

Full Text Available Concrete is the most sought after material due to increase in construction activities and infrastructural developments. Availability of natural sand is decreasing thereby increase in the cost of construction. In the present work undertaken, an attempt has been made to give an alternative to natural sand. Optimization of replacement of natural sand with manufactured sand in concrete, durability studies such as water absorption, rapid chloride permeability test, sorptivity, acid resistance, alkaline resistance, impact resistance and abrasion resistance of M40 and M50 grades of concrete have been studied with manufactured sand as fine aggregate and compared the results with the conventional sand concrete. The results shows that there is an increase in the durability properties up to 70 % level of replacements of sand with manufactured sand as fine aggregate and for 100 % use of manufactured sand also gives the better durability than the conventional sand concrete.

A risk-based approach for identifying constituents of concern in oil sands process-affected water from the Athabasca Oil Sands region.

Science.gov (United States)

McQueen, Andrew D; Kinley, Ciera M; Hendrikse, Maas; Gaspari, Daniel P; Calomeni, Alyssa J; Iwinski, Kyla J; Castle, James W; Haakensen, Monique C; Peru, Kerry M; Headley, John V; Rodgers, John H

2017-04-01

Mining leases in the Athabasca Oil Sands (AOS) region produce large volumes of oil sands process-affected water (OSPW) containing constituents that limit beneficial uses and discharge into receiving systems. The aim of this research is to identify constituents of concern (COCs) in OSPW sourced from an active settling basin with the goal of providing a sound rational for developing mitigation strategies for using constructed treatment wetlands for COCs contained in OSPW. COCs were identified through several lines of evidence: 1) chemical and physical characterization of OSPW and comparisons with numeric water quality guidelines and toxicity endpoints, 2) measuring toxicity of OSPW using a taxonomic range of sentinel organisms (i.e. fish, aquatic invertebrates, and a macrophyte), 3) conducting process-based manipulations (PBMs) of OSPW to alter toxicity and inform treatment processes, and 4) discerning potential treatment pathways to mitigate ecological risks of OSPW based on identification of COCs, toxicological analyses, and PBM results. COCs identified in OSPW included organics (naphthenic acids [NAs], oil and grease [O/G]), metals/metalloids, and suspended solids. In terms of species sensitivities to undiluted OSPW, fish ≥ aquatic invertebrates > macrophytes. Bench-scale manipulations of the organic fractions of OSPW via PBMs (i.e. H 2 O 2 +UV 254 and granular activated charcoal treatments) eliminated toxicity to Ceriodaphnia dubia (7-8 d), in terms of mortality and reproduction. Results from this study provide critical information to inform mitigation strategies using passive or semi-passive treatment processes (e.g., constructed treatment wetlands) to mitigate ecological risks of OSPW to aquatic organisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

Model test study of evaporation mechanism of sand under constant atmospheric condition

OpenAIRE

CUI, Yu Jun; DING, Wenqi; SONG, Weikang

2014-01-01

The evaporation mechanism of Fontainebleau sand using a large-scale model chamber is studied. First, the evaporation test on a layer of water above sand surface is performed under various atmospheric conditions, validating the performance of the chamber and the calculation method of actual evaporation rate by comparing the calculated and measured cumulative evaporations. Second,the evaporation test on sand without water layer is conducted under constant atmospheric condition. Both the evoluti...

Effects of Watering and Fertilization on Carbohydrate Reserves in Sugar Maple Seedlings

Science.gov (United States)

Clayton M., Jr. Carl; John R. Donnelly; Boyd W. Post

1978-01-01

Sugar maple seedlings, grown under three nutrient and three moisture levels, were analyzed after three growing seasons for starch and ethanol-soluble sugars. Analytical procedures are detailed in the appendix. Fertilization did not affect carbohydrate levels in stems or roots. Water stress caused a significant reduction in the amount of carbohydrates in stems and roots...

Compressive Strength of Compacted Clay-Sand Mixes

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Faseel Suleman Khan

2014-01-01

Full Text Available The use of sand to improve the strength of natural clays provides a viable alternative for civil infrastructure construction involving earthwork. The main objective of this note was to investigate the compressive strength of compacted clay-sand mixes. A natural clay of high plasticity was mixed with 20% and 40% sand (SP and their compaction and strength properties were determined. Results indicated that the investigated materials exhibited a brittle behaviour on the dry side of optimum and a ductile behaviour on the wet side of optimum. For each material, the compressive strength increased with an increase in density following a power law function. Conversely, the compressive strength increased with decreasing water content of the material following a similar function. Finally, the compressive strength decreased with an increase in sand content because of increased material heterogeneity and loss of sand grains from the sides during shearing.

Preparation and properties of a coated slow-release and water-retention biuret phosphoramide fertilizer with superabsorbent.

Science.gov (United States)

Jin, Shuping; Yue, Guoren; Feng, Lei; Han, Yuqi; Yu, Xinghai; Zhang, Zenghu

2011-01-12

In this investigation, a novel water-insoluble slow-release fertilizer, biuret polyphosphoramide (BPAM), was formulated and synthesized from urea, phosphoric acid (H(3)PO(4)), and ferric oxide (Fe(2)O(3)). The structure of BPAM was characterized by Fourier transform infrared (FTIR) spectroscopy. Subsequently, a coated slow-release BPAM fertilizer with superabsorbent was prepared by ionic cross-linked carboxymethylchitosan (the core), acrylic acid, acrylamide, and active carbon (the coating). The variable influences on the water absorbency were investigated and optimized. Component analysis results showed that the coated slow-release BPAM contained 5.66% nitrogen and 11.7% phosphorus. The property of water retention, the behavior of slow release of phosphorus, and the capacity of adsorption of cations were evaluated, and the results revealed that the product not only had good slow-release property and excellent water retention capacity but also higher adsorption capacities of cations in saline soil.

Removal of heavy metals using a microbial active, continuously operated sand filter

International Nuclear Information System (INIS)

Ebner, C.

2001-01-01

Heavy metals play an important role within the spectrum of the various pollutants, emitted into the environment via human activities. In contrast to most organic pollutants, heavy metal can not be degraded. Many soils, lakes and rivers show a high contamination with heavy metals due to the enrichment of these pollutants. In addition to existing chemical-physical and biological technologies for the treatment of heavy metal containing waste waters a demand for new, efficient and low-cost cleaning technologies exists, particularly for high volumes of weakly contaminated waters. Such a technology was developed within the framework of a scientific project of the European Union. The approach makes use of a continuously operated, moving-bed Astrasand filter, which has been operated as a continuous biofilm reactor. By inoculation of the reactor with bacteria providing different, defined mechanisms of metal immobilization, and by continuous supply of suitable nutrients, a metal-immobilizing biofilm is built up and regenerated continuously. Metal-enriched biomass is removed continuously from the system, and the contained metals can be recycled by pyrometallurgical treatment of the biomass. The subjects of the present work were the optimization of the nutrient supply for the process of metal removal, the investigation of the toxicity of different waste waters, the optimization of inoculation and biofilm formation, set-up and operation of a lab scale sand filter and the operation of a pilot scale sand filter treating rinsing water of a chemical nickel plating plant. First, basic parameters like toxicity of heavy metal-containing waste waters and the influence of the nutrition of bacteria on biosorption and total metal removal were examined, using freely suspended bacteria in batch culture. Concerning toxicity great differences could be found within the spectrum of heavy metal-containing waste waters tested. Some waters completely inhibited growth, while others did not

Capillary electrophoretic determination of selected phenolic compounds in humic substances of well waters and fertilizers.

Science.gov (United States)

Chen, Mei-Ying; Chang, Yan-Zin; Lu, Fung-Jou; Chen, Jian-Lian

2010-01-01

Humic substances (HS) from well waters, fertilizers, and synthetic phenolic polymers were characterized by elemental and UV-VIS spectroscopic analyses. Capillary zone electrophoresis (CZE) with UV absorption detection was used to analyze the lignin-derived phenolic distribution in the degradation residues after alkaline CuO oxidation of HS samples. Eleven phenols with p-acetyl, vanillyl and syringyl substituents were selected to optimize the CZE parameters. For well waters and fertilizers, the content of phenolic fragments was in agreement with the findings of the elemental and spectroscopic measurements. Additionally, parameters derived from the vanillic acid/vanilline, syringyl acid/syringaldehyde, p-hydroxyl/vanillyl and syringyl/vanillyl ratios matched analogous studies on dissolved organic matter from natural waters and on humic acids from terrestrial substances. The amount of phenolic monomer bonded within two synthetic HS polymers was found to be 25.9% protocatechuic acid and 71.3% gallic acid.

Effects of water content on reactive transport of Sr in Chernobyl sand columns

International Nuclear Information System (INIS)

Szenknect, S.; Dewiere, L.; Ardois, C.; Gaudet, J.P.

2005-01-01

Full text of publication follows: While transport of non-reactive solutes has been studied extensively in unsaturated porous media, much less is known about the factors that control the transport of sorbing solutes in unsaturated conditions. Three laboratory techniques were used to analyze the transport of Sr in the aeolian sand from Chernobyl Pilot Site [1] in both saturated and unsaturated flow conditions. Batch experiments were performed to study the chemical equilibrium state of the soil/solution system. Stirred flow-through reactor (SFTR) experiments were performed to study the kinetics and reversibility of sorption reactions at the surface of solid particles. Column experiments were also performed in saturated and unsaturated steady flow conditions. Experimental data pointed out a non-linear, instantaneous and reversible sorption process of Sr. A suitable cation-exchange model was used to describe the solute/soil reaction. The former model was coupled with transport models to describe behavior of Sr in saturated [2] and unsaturated flow conditions. Transport properties of sand packed columns have been determined with an inert tracer (HTO). BTCs obtained under saturated conditions exhibit a small amount of dispersion compared to those obtained under unsaturated conditions. Classical advection-dispersion model described successfully saturated tritium breakthrough curves (BTCs), whereas a mobile-immobile model (MIM) was required to described asymmetrical unsaturated BTCs. The MIM assumes that the porous medium contains a mobile water phase in which convective-dispersive transport occurs, and a immobile water phase with which solutes can exchange with a first order kinetic. In our experiments, transport by advection in the mobile phase is the predominant process whatever the flow conditions and mass transfer rate between the mobile and immobile regions is the predominant process for broadening the BTCs. Since dispersion is blurred by mass transfer resistance, the

Evaluation of Turf-Grass and Prairie-Vegetated Rain Gardens in a Clay and Sand Soil, Madison, Wisconsin, Water Years 2004-08

Science.gov (United States)

Selbig, William R.; Balster, Nicholas

2010-01-01

The U.S. Geological Survey, in cooperation with a consortium of 19 cities, towns, and villages in Dane County, Wis., undertook a study to compare the capability of rain gardens with different vegetative species and soil types to infiltrate stormwater runoff from the roof of an adjacent structure. Two rain gardens, one planted with turf grass and the other with native prairie species, were constructed side-by-side in 2003 at two locations with different dominant soil types, either sand or clay. Each rain garden was sized to a ratio of approximately 5:1 contributing area to receiving area and to a depth of 0.5 foot. Each rain garden, regardless of vegetation or soil type, was capable of storing and infiltrating most of the runoff over the 5-year study period. Both rain gardens in sand, as well as the prairie rain garden in clay, retained and infiltrated 100 percent of all precipitation and snowmelt events during water years 2004-07. The turf rain garden in clay occasionally had runoff exceed its confining boundaries, but was still able to retain 96 percent of all precipitation and snowmelt events during the same time period. Precipitation intensity and number of antecedent dry days were important variables that influenced when the storage capacity of underlying soils would become saturated, which resulted in pooled water in the rain gardens. Because the rooftop area that drained runoff to each rain garden was approximately five times larger than the area of the rain garden itself, evapotranspiration was a small percentage of the annual water budget. For example, during water year 2005, the maximum evapotranspiration of total influent volume ranged from 21 percent for the turf rain garden in clay to 25 percent for the turf rain garden in sand, and the minimum ranged from 12 percent for the prairie rain garden in clay to 19 percent for the prairie rain garden in sand. Little to no runoff left each rain garden as effluent and a small percentage of runoff returned to the

Ecotoxicological impacts of effluents generated by oil sands bitumen extraction and oil sands lixiviation on Pseudokirchneriella subcapitata

Energy Technology Data Exchange (ETDEWEB)

Debenest, T., E-mail: tdebenest@yahoo.fr [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada); Turcotte, P. [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada); Gagne, F., E-mail: francois.gagne@ec.gc.ca [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada); Gagnon, C.; Blaise, C. [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada)

2012-05-15

The exploitation of Athabasca oil sands deposits in northern Alberta has known an intense development in recent years. This development has raised concern about the ecotoxicological risk of such industrial activities adjacent to the Athabasca River. Indeed, bitumen extraction generated large amounts of oil sands process-affected water (OSPW) which are discharged in tailing ponds in the Athabasca River watershed. This study sought to evaluate and compare the toxicity of OSPW and oil sands lixiviate water (OSLW) with a baseline (oil sands exposed to water; OSW) on a microalgae, Pseudokirchneriella subcapitata, at different concentrations (1.9, 5.5, 12.25, 25 and 37.5%, v/v). Chemical analyses of water-soluble contaminants showed that OSPW and OSLW were enriched in different elements such as vanadium (enrichment factor, EF = 66 and 12, respectively), aluminum (EF = 64 and 15, respectively), iron (EF = 52.5 and 17.1, respectively) and chromium (39 and 10, respectively). The toxicity of OSPW on cells with optimal intracellular esterase activity and chlorophyll autofluorescence (viable cells) (72 h-IC 50% < 1.9%) was 20 times higher than the one of OSW (72 h-IC 50% > 37.5%, v/v). OSLW was 4.4 times less toxic (IC 50% = 8.5%, v/v) than OSPW and 4.5 times more toxic than OSW. The inhibition of viable cell growth was significantly and highly correlated (<-0.7) with the increase of arsenic, beryllium, chromium, copper, lead, molybdenum and vanadium concentrations. The specific photosynthetic responses studied with JIP-test (rapid and polyphasic chlorophyll a fluorescence emission) showed a stimulation of the different functional parameters (efficiency of PSII to absorb energy from photons, size of effective PSII antenna and vitality of photosynthetic apparatus for energy conversion) in cultures exposed to OSPW and OSLW. To our knowledge, our study highlights the first evidence of physiological effects of OSPW and OSLW on microalgae.

Impact of Nitrogen Fertilization on Forest Carbon Sequestration and Water Loss in a Chronosequence of Three Douglas-Fir Stands in the Pacific Northwest

Directory of Open Access Journals (Sweden)

Xianming Dou

2015-05-01

Full Text Available To examine the effect of nitrogen (N fertilization on forest carbon (C sequestration and water loss, we used an artificial neural network model to estimate C fluxes and evapotranspiration (ET in response to N fertilization during four post-fertilization years in a Pacific Northwest chronosequence of three Douglas-fir stands aged 61, 22 and 10 years old in 2010 (DF49, HDF88 and HDF00, respectively. Results showed that N fertilization increased gross primary productivity (GPP for all three sites in all four years with the largest absolute increase at HDF00 followed by HDF88. Ecosystem respiration increased in all four years at HDF00, but decreased over the last three years at HDF88 and over all four years at DF49. As a result, fertilization increased the net ecosystem productivity of all three stands with the largest increase at HDF88, followed by DF49. Fertilization had no discernible effect on ET in any of the stands. Consequently, fertilization increased water use efficiency (WUE in all four post-fertilization years at all three sites and also increased light use efficiency (LUE of all the stands, especially HDF00. Our results suggest that the effects of fertilization on forest C sequestration and water loss may be associated with stand age and fertilization; the two younger stands appeared to be more efficient than the older stand with respect to GPP, WUE and LUE.

Ecological restoration and recovery in the wind-blown sand hazard areas of northern China: relationship between soil water and carrying capacity for vegetation in the Tengger Desert.

Science.gov (United States)

Li, XingRong; Zhang, ZhiShan; Tan, HuiJuan; Gao, YanHong; Liu, LiChao; Wang, XingPing

2014-05-01

The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km(2) in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain. Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas. After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert, we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water. The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition. The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession. The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed.

Magnesium nutrition of apple trees. III. Comparison of different methods of magnesium fertilization

Directory of Open Access Journals (Sweden)

A. Sadowski

2015-06-01

Full Text Available In the period 1969-1973 two experiments were performed in young orchards in Central Poland: a four-year experiment at Julianów, on sandy loamy soil on underlying sand and one-year experiment at Kośmin, on sandy loam soil on clay loam. At Kosmin, in spite of a high Mg content in the subsoil, Mg deficiency symptoms appeared, because of shallow rooting owing to poor aeration. In both experiments, foliar sprays with epsomite were less effective than fertilization to the soil; at Kośmin even eight sprays were less effective than soil dressings. Mg losses from a sandy soil due to leaching were high, particularly where sand was present in the whole profile; under these conditions the least losses of Mg were from split doses of epsomite (Mg3x120. Single doses of epsomite were the most effective in increasing leaf Mg content, reducing Mg deficiency symptoms and promoting growth of trees in the first year after application; in the later years split doses of epsomite and a single initial dose of magnesium lime were more effective. Effects of Mg fertilization on growth and yields of apples were rather slight, when K fertilizer doses were low. No effect of Mg fertilization upon fruit drop and fruit quality was found. Preliminary recommendations for practice are given.

Heavy mineral sorting as a tool to distinguish depositional characteristics of “in situ” sands from their related injected sands in a Palaeogene submarine Canyon, Danish North Sea

DEFF Research Database (Denmark)

Moatari Kazerouni, Afsoon; Friis, Henrik; Svendsen, Johan. B

Postdepositional remoblization and injection of sand are important processes in deep-water clastic systems. Subsurface mobilisation and injection of sand has been recently recognised as a significant control of deep-water sandstone geometry. Kilometre-scale injection complexes have been interpreted...

Pathogen removal using saturated sand colums supplemented with hydrochar

NARCIS (Netherlands)

Chung, J.W.

2015-01-01

This PhD study has evaluated hydrochars derived from biowastes as adsorbents for pathogen removal in water treatment. Pathogen removal experiments were conducted by carrying out breakthrough analysis using a simple sand filtration set-up. Glass columns packed by 10 cm sand bed supplemented with

ARSENIC REMOVAL FROM DRINKING WATER BY ADSORPTIVE MEDIA - USEPA DEMONSTRATION PROJECT AT DESERT SANDS MDWCA, NM SIX MONTH EVALUATION

Science.gov (United States)

This report documents the activities performed during, and the results obtained from, the first six months of the arsenic removal treatment technology demonstration project at the Desert Sands Mutual Domestic Water Consumers Association (MDWCA) facility in Anthony, NM. The object...

Radium desorption, manganese and iron dissolution from sand filters of a conventional ground water treatment plant under reductive conditions

International Nuclear Information System (INIS)

Al-Hobaib, A.S.; Al-Sulaiman, K.M.; Al-Dhayan, D.M.; Al-Suhybani, A.A.

2006-01-01

Sand filters are used as a filter bed in many ground water treatment plants to remove the physical contaminants and oxidation products. A build-up of radioactivity may take place on the granules, where iron and manganese oxides are deposited and form thin films on the surface of sand filter. The oxides of iron and manganese play an important role in adsorbing radium from ground water. The disposal of those granules makes a significant problem. A batch technique is used for solubilization of radium from sand filters in the presence of some organic acids, which act as reducing agents. These acids are formic acid, acetic acid, benzoic acid, succinic acid, oxalic acid, phthalic acid, and adipic acid. The data were obtained as a function of acidity, temperature, contact time and liquid/solid ratio particle size and shaking speed. It was found that oxalic acid was the best for radium removal. The effectiveness of these acids on radium removal was as follows: oxalic acid > phthalic acid > adipic acid > succinic acid > formic acid > acetic acid. The maximum removal obtained was 69.9% at 1M oxalic acid at 8 ml/g ratio. Reaction kinetics and mechanism parameters of the dissolution process were studied and compared with other published data. (author)

The behavior of gaseous iodine in sand

International Nuclear Information System (INIS)

Takahashi, Kanji

1974-01-01

Radioactive iodine gas was passed through 10 different sands collected at rivers and hills. The relation between the amount of the loaded gas and the amount of adsorbed gas was determined at room temperature, 50 -- 60 0 C, and 90 -- 100 0 C under humidity of 2 sand. This amount was about 1 -- 3 times as much as that of monomolecular membrane adsorption, 0.2 -- 0.3 μg/cm 2 . The decrease of adsorption amount that accompanies the increase of humidity is attributable to the decrease of effective surface area of sand due to the presence of water. The transport of iodine in sand was studied by passing gaseous iodine through a glass tubing packed with sand. The distribution in the flow direction of iodine indicated that the ease of desorption depends upon the situation of adsorption. Easily desorbed case was named Henry type adsorption. Hardly desorbed case was named absorption type. Discussion is made on experimental results. (Fukutomi, T.)

Research for the development of the crushed sand (II)

Energy Technology Data Exchange (ETDEWEB)

Park, Chul Whan; Kang, Sun Duck; Min, Jeong Sik; Synn, Joong Ho; Park, Chan [Korea Institute of Geology Mining and Materials, Taejon (Korea)

1998-12-01

The sand obtained from river is not sufficient in amount for the demand of construction industry. The production of sand from sea and mountain is rapidly increasing for the substitution of the river sand. The industry of the crushed sand has recently been bricked for the above. Crushing, classification and dewatering are the main processes in the crushed sand production. This report concentrates the improvement of classification technology and the quality of ready mixed concrete. Air separator with testing size for the classification in the process of dry system was developed by the Yeung Nam university. This plant has the excellent efficiency for the collection of fine powder, but needs the improvement for separating function. The collection efficiency of the testing size air separator is reached to 99% in the condition of high revolution and low feeding speed. The classification efficiency is checked about 50% maximum in the condition of 200 rpm and dry sample. Energy saving test was carried out in the production process of the dry system with the rock samples of 14-17% of water content. The classification efficiency for dewatering sample passed the heating process was analysed 91.5%. But that for high water content sample skipped the heating process was analysed more or less 77%. Even though the heating process causes the classification efficiency being high, the energy consumption can also cause the price of the crushed sand high. Water content of sample as the effective element for the optimization of classification efficiency and energy saving should be studied next year. The quality of crushed sand in the mixing design. The test was carried out with the various content in mixing, the strength of ready mixed concrete has the maximum for the mould with 50-60% content of crushed sand. This strength is higher by 5-30% than 30% content and by 20-32% than 0% content, which means that the industry has the possibility of progress. (author). 10 refs., 31 tabs., 49

Enhanced mobility of non aqueous phase liquid (NAPL) during drying of wet sand

Science.gov (United States)

Govindarajan, Dhivakar; Deshpande, Abhijit P.; Raghunathan, Ravikrishna

2018-02-01

Enhanced upward mobility of a non aqueous phase liquid (NAPL) present in wet sand during natural drying, and in the absence of any external pressure gradients, is reported for the first time. This mobility was significantly higher than that expected from capillary rise. Experiments were performed in a glass column with a small layer of NAPL-saturated sand trapped between two layers of water-saturated sand. Drying of the wet sand was induced by flow of air across the top surface of the wet sand. The upward movement of the NAPL, in the direction of water transport, commenced when the drying effect reached the location of the NAPL and continued as long as there was significant water evaporation in the vicinity of NAPL, indicating a clear correlation between the NAPL rise and water evaporation. The magnitude and the rate of NAPL rise was measured at different water evaporation rates, different initial locations of the NAPL, different grain size of the sand and the type of NAPL (on the basis of different NAPL-glass contact angle, viscosity and density). A positive correlation was observed between average rate of NAPL rise and the water evaporation while a negative correlation was obtained between the average NAPL rise rate and the NAPL properties of contact angle, viscosity and density. There was no significant correlation of average NAPL rise rate with variation of sand grain size between 0.1 to 0.5 mm. Based on these observations and on previous studies reported in the literature, two possible mechanisms are hypothesized -a) the effect of the spreading coefficient resulting in the wetting of NAPL on the water films created and b) a moving water film due to evaporation that "drags" the NAPL upwards. The NAPL rise reported in this paper has implications in fate and transport of chemicals in NAPL contaminated porous media such as soils and exposed dredged sediment material, which are subjected to varying water saturation levels due to drying and rewetting.

Conversion of sand filters into activated carbon filters at the La Presa (Valencia) water works; Conversion de filtros de arena porcarbon activo en la ETAP de La Presa (Valencia)

Energy Technology Data Exchange (ETDEWEB)

Macian Cervera, V. J.; Monforte Monleon, L.; Ribera Orts, R.; Suris Jorda, J. I.; Klee, J. M.

2007-07-01

To improve the water quality at potable water treatment plant of La P esa (Valencia), the sand filters have been replaced for activated carbon filters. In the following review the results and conclusions of the direct sand filter conversion into activated carbon filters will be presented. The leads to a simple and fast solution to odour and taste removal, as well as dissolved organic matter, without investments in works at the water works. (Author)

Responses of woody species to spatial and temporal ground water changes in coastal sand dune systems

Directory of Open Access Journals (Sweden)

C. Máguas

2011-12-01

Full Text Available In spite of the relative importance of groundwater in costal dune systems, studies concerning the responses of vegetation to ground water (GW availability variations, particularly in Mediterranean regions, are scarce. Thus, the main purpose of this study is to compare the responses of co-occurring species possessing different functional traits, to changes in GW levels (i.e. the lowering of GW levels in a sand dune ecosystem. For that, five sites were established within a 1 km² area in a meso-mediterranean sand dune ecosystem dominated by a Pinus pinaster forest. Due to natural topographic variability and anthropogenic GW exploitation, substantial variability in depth to GW between sites was found. Under these conditions it was possible to identify the degree of usage and dependence on GW of different plant species (two deep-rooted trees, a drought adapted shrub, a phreatophyte and a non-native woody invader and how GW dependence varied seasonally and between the heterogeneous sites. Results indicated that the plant species had differential responses to changes in GW depth according to specific functional traits (i.e. rooting depth, leaf morphology, and water use strategy. Species comparison revealed that variability in pre-dawn water potential (Ψ_pre and bulk leaf δ¹³C was related to site differences in GW use in the deep-rooted (Pinus pinaster, Myrica faya and phreatophyte (Salix repens species. However, such variation was more evident during spring than during summer drought. The exotic invader, Acacia longifolia, which does not possess a very deep root system, presented the largest seasonal variability in Ψ_pre and bulk leaf δ¹³C. In contrast, the response of Corema album, an endemic understory drought-adapted shrub, seemed to be independent of water availability across seasons and sites. Thus, the susceptibility to lowering of GW due to anthropogenic

Faunistic assemblages of a sublittoral coarse sand habitat of the northwestern Mediterranean

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Eva Pubill

2011-02-01

Full Text Available The sublittoral megabenthic assemblages of a northwestern Mediterranean coarse sandy beach exploited for the bivalve Callista chione were studied. The spatial and bathymetric variability of its distinctive faunal assemblages was characterised by quantitative sampling performed with a clam dredge. The taxa studied were Mollusca Bivalvia and Gastropoda, Crustacea Decapoda, Echinodermata and Pisces, which accounted for over 99% of the total biomass. Three well-differentiated species assemblages were identified: (1 assemblage MSS (Medium Sand Shallow in medium sand (D50=0.37 mm and shallow waters (mean depth =6.5 m, (2 assemblage CSS (Coarse Sand Shallow in coarse sand (D50=0.62 mm in shallow waters (mean depth =6.7 m, and (3 assemblage CSD (Coarse Sand Deep in coarse sand (D50=0.64 mm in deeper waters (mean depth =16.2 m. Assemblage MSS was characterised by the codominance of the bivalves Mactra stultorum and Acanthocardia tuberculata. C. chione was dominant in both density and biomass in assemblages CSS and CSD. The occurrence of the crab Thia scutellata also characterised assemblage CSS, whereas the occurrence of the sea urchin Echinocardium mediterraneum characterised assemblage CSD. A depth breaking point of around 10 m determined the discontinuity between assemblages CSS and CSD, which was related to the closure depth of the beaches in the study area. Species richness was highest in the coarse sand communities; however, Shannon-Wiener diversity and Pielou equitability indexes were higher in the shallow fine sand community.

Long-term Root Growth Response to Thinning, Fertilization, and Water Deficit in Plantation Loblolly Pine

Science.gov (United States)

M.A. Sword-Sayer; Z. Tang

2004-01-01

High water deficits limit the new root growth of loblolly pine (Pinus taeda L.), potentially reducing soil resource availability and stand growth. We evaluated new root growth and stand production in response to thinning and fertilization in loblolly pine over a 6-year period that consisted of 3 years of low water deficit followed by 3 years of high...

Measuring P availability in soils fertilized with water-soluble P fertilizers using 32P methodologies

International Nuclear Information System (INIS)

McLaughlin, M.J.

2002-01-01

Isotope exchange kinetics was used in conjunction with standard procedures for assessing soil P status in soils fertilized with soluble phosphatic fertilizers. Soil samples were collected before fertilizer application in year 1 (one) from 23 of the 30 sites of the National Reactive Phosphate Rock project. Soil phosphorus test values were plotted against indices of pasture response to applied fertilizer, to assess the effectiveness of the various soil tests to predict site responsiveness to applied fertilizer. Isotopically exchangeable P was only weakly related to other measures of available P, with resin P having the best relationship with E values. In some samples, very large values for isotopically exchangeable P (E values) were determined in relation to P extractable by all reagents. Examination of the data however, revealed that all the samples with large E values in relation to extractable P had very low equilibrium concentrations of solution P and high buffering capacities. The best soil test, Bray 1, could account for only 50% of the variation in plant responsiveness to applied fertilizer, with Olsen and Resin tests slightly worse at 41% and the isotopic procedure at 39%. (author)

Physiology of ‘Paluma’ guava under irrigation with saline water and nitrogen fertilization

Directory of Open Access Journals (Sweden)

Evandro Manoel da Silva

2017-05-01

Full Text Available The use of saline water in irrigation causes osmotic and toxic effects and nutritional imbalance in plants, leading to morphophysiological modifications in the leaves and compromising the production of photosynthetic pigments, which negatively reflects in the growth and development of the crops. Hence, this study aimed to evaluate the effect of irrigation water salinity on the content of photosynthetic pigments and leaf morphophysiology of guava seedlings cv. ‘Paluma’ under nitrogen (N fertilization. A randomized block design was used, testing five levels of irrigation water electrical conductivity - ECw (0.3, 1.1, 1.9, 2.7, and 3.5 dS m-1 and four N doses (541.1, 773.0, 1,004.9, and 1,236.8 mg of N dm-3 of soil in a 5 x 4 factorial scheme with three replicates and five plants per plot. The contents of photosynthetic pigments in the leaves of the guava seedlings cv. ‘Paluma’ were inhibited by the increase in irrigation water salinity at 190 days after emergence, and the salt stress was lessened with the N dose of 1,004.9 mg dm-3 up to an ECw level of 1.2 dS m-1. Leaf morphophysiology of guava seedlings was not compromised by irrigation water salinity up to 1.5 dS m-1, and the highest values were obtained in plants fertilized with 541.1 mg of N dm-3.

Groundwater Discharges to Rivers in the Western Canadian Oil Sands Region

Science.gov (United States)

Ellis, J.; Jasechko, S.

2016-12-01

Groundwater discharges into rivers impacts the movement and fate of nutrients and contaminants in the environment. Understanding groundwater-surface water interactions is especially important in the western Canadian oil sands, where groundwater contamination risks are elevated and baseline water chemistry data is lacking, leading to substantial uncertainties about anthropogenic influences on local river quality. High salinity groundwater springs sourced from deep aquifers, comprised of Pleistocene-aged glacial meltwater, are known to discharge into many rivers in the oil sands. Understanding connections between deep aquifers and surficial waterways is important in order to determine natural inputs into these rivers and to assess the potential for injected wastewater or oil extraction fluids to enter surface waters. While these springs have been identified, their spatial distribution along rivers has not been fully characterized. Here we present river chemistry data collected along a number of major river corridors in the Canadian oil sands region. We show that saline groundwater springs vary spatially along the course of these rivers and tend to be concentrated where the rivers incise Devonian- or Cretaceous-aged aquifers along an evaporite dissolution front. Our results suggest that water sourced from Devonian aquifers may travel through bitumen-bearing Cretaceous units and discharge into local rivers, implying a strong groundwater-surface water connection in specialized locations. These findings indicate that oil sands process-affected waters that are injected at depth have the potential to move through these aquifers and reach the rivers at the surface at some time in the future. Groundwater-surface water interactions remain key to understanding the risks oil sands activities pose to aquatic ecosystems and downstream communities.

Effects of nitrogen fertilization and grazing on the emission of nitrous oxide from grassland

Energy Technology Data Exchange (ETDEWEB)

Velthof, G.L.; Brader, A.B.; Oenema, O. [NMI, Dept. of Soil Science and Plant Nutrition, Wageningen Agricultural Univ. (Netherlands)

1995-11-01

In the Netherlands, managed grasslands are potentially a large source of nitrous oxide (N{sub 2}O), because of the large nitrogen (N) input and the relatively high ground water levels. To provide insight into the major factors that contribute to N{sub 2}O emission from grassland and to provide quantitative N{sub 2}O emission rates, a monitoring study was carried out on four sites, during March 1992 to March 1994. Fluxes of N{sub 2}O increased after N fertilizer application and grazing, especially during wet conditions. Fluxes were higher from peat soils than from sand and clay soils. Fluxes were low during the winter periods. Total N{sub 2}O losses were 2 to 4.5 times higher on grassland fertilized with 160-460 kg N ha{sup -1} yr{sup -1} than on unfertilized grassland. Losses from grazed grasslands were 1.5 to 3.5 times higher than losses from mown grassland. This study shows that management practice of grassland and soil type are major factors controlling N{sub 2}O emission from grasslands. 2 figs., 3 refs.

Preparation and properties of a double-coated slow-release NPK compound fertilizer with superabsorbent and water-retention.

Science.gov (United States)

Wu, Lan; Liu, Mingzhu; Rui Liang

2008-02-01

A double-coated slow-release NPK compound fertilizer with superabsorbent and water-retention was prepared by crosslinked poly(acrylic acid)/diatomite - containing urea (the outer coating), chitosan (the inner coating), and water-soluble granular fertilizer NPK (the core). The effects of the amount of crosslinker, initiator, degree of neutralization of acrylic acid, initial monomer and diatomite concentration on water absorbency were investigated and optimized. The water absorbency of the product was 75 times its own weight if it was allowed to swell in tap water at room temperature for 2 h. Atomic absorption spectrophotometer and element analysis results showed that the product contained 8.47% potassium (shown by K(2)O), 8.51% phosphorus (shown by P(2)O(5)), and 15.77% nitrogen. We also investigated the water-retention property of the product and the slow release behavior of N, P and K in the product. This product with excellent slow release and water-retention capacity, being nontoxic in soil and environment-friendly, could be especially useful in agricultural and horticultural applications.

High Temperature Thermal Properties of Bentonite Foundry Sand

Directory of Open Access Journals (Sweden)

Krajewski P.K.

2015-06-01

Full Text Available The paper presents results of measuring thermal conductivity and heat capacity of bentonite foundry sand in temperature range ambient - 900­­°C. During the experiments a technical purity Cu plate was cast into the green-sand moulds. Basing on measurements of the mould temperature field during the solidification of the casting, the temperature relationships of the measured properties were evaluated. It was confirmed that water vaporization strongly influences thermal conductivity of the moulding sand in the first period of the mould heating by the poured casting.

Evaluate Effect of Water Stress and Different Amounts of Nitrogen Fertilizer on Seed Quality of Black Cumin (Nigella Sativa L

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M Heidari

2014-03-01

Full Text Available In order to study the effects of water stress and different levels of nitrogen fertilizer on grian yield and accumulation macronutrients included: nitrogen, phosphorus and potassium and micronutrient included: iron, zinc, manganese and copper, oil, protein and thymoquinone contents in seed of black cumin, a field experiment was conducted as split plot design with three replications at Agricultural Research Station, Zahak, Zabol during growing season of 2010-2011. Water stress treatments included: W1= control, W2= no irrigation at stem elongation stage to flowering, W3= irrigation at flowering stage until the beginning of grain filling and W4= no irrigation at flowering and grain filling as the main plots and four levels of nitrogen application fertilizer, including N1= control or without any fertilizer consumption, N2= 30 kg N/ha, N3= 60 kg N/ha and N4= 90 kg N/ha in sub plot. Results showed that water stress had significant effect on the grain yield and accumulation of macro and micronutrient in the seed of Black Cumin. Except for and iron, the highest amounts of nitrogen, phosphorus, potassium, manganese, copper and zinc and the lowest amount of grain yield were obtained at W4 treatment and manganese at W3 treatment. In this experiment the interaction effect between stress and nitrogen fertilizer except grain yield and potassium had significant impact on others elements. The results indicated that water stress at flowering and grain filling (W4 stages, the maximum amount of micro and macronutrients in seed was obtained at N1 and N2 nitrogen treatment. Also, water stress and nitrogen treatments increased the percentage of protein, oil and thymoquinone contents of seed, but during the onset of water stress and the use of nitrogen fertilizer, the highest percentage of protein in and thymoquinone were obtained in W4N4.

Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

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Nirmala D.B.

2016-06-01

Full Text Available This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37 Orthogonal Arrays (OA with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering “Nominal the better” situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

Science.gov (United States)

Nirmala, D. B.; Raviraj, S.

2016-06-01

This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC) containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37) Orthogonal Arrays (OA) with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering "Nominal the better" situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

Rheology of oil sands slurries

Energy Technology Data Exchange (ETDEWEB)

Chow, R.; Zhou, J. [Alberta Research Council, Edmonton, AB (Canada). Mineral Oil Sands Unit; Wallace, D. [Dean Wallace Consulting Inc., Beaumont, AB (Canada)

2006-07-01

This study focused on integrating rheology and colloid science to improve recovery of bitumen in surface mined oil sands. Factors that influence recovery, such as conditions of particle interaction, solids concentration and shear rate, were reviewed. In an effort to understand the rheological behaviour of clay-in-water suspensions, an elaborate procedure was developed to separate an inter-bedded clay layer from a site at Albian Sands Energy Inc. The variables were water chemistry, solids concentration, and shear rate. The research study was conducted at the Alberta Research Council with the support of the CONRAD Extraction Group. A controlled stress rheometer was used to provide the quantitative evaluations of the clay slurry properties. The research results indicate that the viscoelastic properties of the slurry are highly influenced by the shear history of the slurry, solids content, calcium concentration, and sample aging. Shear thinning behaviour was observed in all slurry samples, but the slurry viscosity increased with test time for a given shear rate. In order to classify the slurries, a method was developed to distinguish the gel strength. The slurries were then classified into 3 distinct patterns, including no gel, weak gel and strong gel. The evolution of the experimental protocols were described along with the current stability maps that correlate the domains of the gel strength according to the solids concentration, calcium ion content, and shear rate. It was concluded that the rheological properties of oil sands slurries influence bitumen recovery in commercial surface-mined oil sands operations. tabs., figs.

Optimizing nitrification in biological rapid sand filters for drinking water production

DEFF Research Database (Denmark)

Albrechtsen, Hans-Jørgen; Smets, Barth F.; Lee, Carson Odell

Addition of phosphate or trace metals or better management e.g. in terms of anmonium load can improve the nitrification rate and efficiency in biological rapid sand filters.......Addition of phosphate or trace metals or better management e.g. in terms of anmonium load can improve the nitrification rate and efficiency in biological rapid sand filters....

In situ recovery of oil from Utah tar sand: a summary of tar sand research at the Laramie Energy Technology Center

Energy Technology Data Exchange (ETDEWEB)

Marchant, L.C.; Westhoff, J.D.

1985-10-01

This report describes work done by the United States Department of Energy's Laramie Energy Technology Center from 1971 through 1982 to develop technology for future recovery of oil from US tar sands. Work was concentrated on major US tar sand deposits that are found in Utah. Major objectives of the program were as follows: determine the feasibility of in situ recovery methods applied to tar sand deposits; and establish a system for classifying tar sand deposits relative to those characteristics that would affect the design and operation of various in situ recovery processes. Contents of this report include: (1) characterization of Utah tar sand; (2) laboratory extraction studies relative to Utah tar sand in situ methods; (3) geological site evaluation; (4) environmental assessments and water availability; (5) reverse combustion field experiment, TS-1C; (6) a reverse combustion followed by forward combustion field experiment, TS-2C; (7) tar sand permeability enhancement studies; (8) two-well steam injection experiment; (9) in situ steam-flood experiment, TS-1S; (10) design of a tar sand field experiment for air-stream co-injection, TS-4; (11) wastewater treatment and oil analyses; (12) economic evaluation of an in situ tar sand recovery process; and (13) appendix I (extraction studies involving Utah tar sands, surface methods). 70 figs., 68 tabs.

Cultivation of CNPA G3 sesame irrigated with saline water and fertilized with nitrate-N and ammonium-N

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Geovani S. de Lima

Full Text Available ABSTRACT The study aimed to evaluate the effects of irrigation with saline water and fertilization with nitrate (NO3--N and ammonium (NH4+-N ratios on growth, flowering, water consumption and water use efficiency of the sesame cv. CNPA G3. The treatments were distributed in randomized blocks in a 5 x 5 factorial with three replicates, referring to five levels of electrical conductivity of the irrigation water - ECw (0.6, 1.2, 1.8, 2.4 and 3.0 dS m-1 and nitrate (NO3--N and ammonium (NH4+-N (200/0, 150/50, 100/100, 50/150, 0/200 mg kg-1 ratios. Irrigation with saline water above 0.6 dS m-1 inhibited the growth, delayed flowering and promoted early maturation of capsules of sesame, cv. CNPA G3. The proportion of 0/200 mg kg-1 of NO3--N/NH4+-N promoted the greatest increase relative to stem diameter and height of sesame plants. Water consumption decreases with increasing ECw and was significantly lower in plants fertilized with the proportion of 0/200 of NO3--N/NH4+-N. The interaction between ECw levels and ammonium/nitrate proportions significantly affect water use efficiency, and the highest value was obtained with ECw of 0.6 dS m-1 and fertilization with 150:50 mg kg-1 of NO3--N and NH4+-N.

Mecoprop (MCPP) removal in full-scale rapid sand filters at a groundwater-based waterworks

DEFF Research Database (Denmark)

Hedegaard, Mathilde Jørgensen; Arvin, Erik; Corfitzen, Charlotte B.

2014-01-01

and secondary rapid sand filters. Water quality parameters were measured throughout the waterworks, and they behaved as designed for. MCPP was removed in secondary rapid sand filters — removal was the greatest in the sand filters in the filter line with the highest contact time (63min). In these secondary sand...... in the full-scale system. Therefore, microcosms were set up with filter sand, water and 14C-labelled MCPP at an initial concentration of 0.2μg/L. After 24h, 79–86% of the initial concentration of MCPP was removed. Sorption removed 11–15%, while the remaining part was removed by microbial processes, leading...... to a complete mineralisation of 13–18%. Microbial removal in the filter sand was similar at different depths of the rapid sand filter, while the amount of MCPP which adsorbed to the filter sand after 48h decreased with depth from 21% of the initial MCPP in the top layer to 7% in the bottom layer...

Environmental Impacts of Sand Exploitation. Analysis of Sand Market

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Marius Dan Gavriletea

2017-06-01

Full Text Available Sand is an indispensable natural resource for any society. Despite society’s increasing dependence on sand, there are major challenges that this industry needs to deal with: limited sand resources, illegal mining, and environmental impact of sand mining. The purpose of this paper is twofold: to present an overview of the sand market, highlighting the main trends and actors for production, export and import, and to review the main environmental impacts associated with sand exploitation process. Based on these findings, we recommend different measures to be followed to reduce negative impacts. Sand mining should be done in a way that limits environmental damage during exploitation and restores the land after mining operations are completed.

Retempering of Concrete made by using Manufactured Sand

Science.gov (United States)

Pethkar, A. R.; Deshmukh, G.

2014-06-01

Retempering is defined as, " Addition of water and remixing of concrete or mortar which has lost enough workability to become unplaceable". Retempering inevitably results in some loss of strength compared with the original concrete [1]. Adding water to a plastic mix to increase slump is an extremely common practice, even though it is not recommended because it increases the porosity of concrete. Concrete often arrives on site more than half an hour after initial mixing. Placement operations can take anywhere from 10 to 60 min, depending on the field conditions and the size of the load. When the slump decreases to an unacceptable level during the operations, water is added to the mix [1]. In this work, an attempt is made to study the strength characteristics of retempered concrete made by using manufactured sand. Usually the retempering process is there with normal and ready mixed concrete; hence an attempt is made to check the compressive and flexural strength of normal retempered concrete with an addition of retarder 0.2, 0.4 and 0.6 % at retempering time from 15 to 90 min. There is scarcity of natural sand due to various factors, which is replaced by the manufactured sand. The concept of manufactured sand is nothing but breaking stone into smaller and smaller particles in such way that the gradation of particle will match with zone-II of I.S.

Varying Inundation Regimes Differentially Affect Natural and Sand-Amended Marsh Sediments.

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C Wigand

Full Text Available Climate change is altering sea level rise rates and precipitation patterns worldwide. Coastal wetlands are vulnerable to these changes. System responses to stressors are important for resource managers and environmental stewards to understand in order to best manage them. Thin layer sand or sediment application to drowning and eroding marshes is one approach to build elevation and resilience. The above- and below-ground structure, soil carbon dioxide emissions, and pore water constituents in vegetated natural marsh sediments and sand-amended sediments were examined at varying inundation regimes between mean sea level and mean high water (0.82 m NAVD88 to 1.49 m NAVD88 in a field experiment at Laws Point, part of the Plum Island Sound Estuary (MA. Significantly lower salinities, pH, sulfides, phosphates, and ammonium were measured in the sand-amended sediments than in the natural sediments. In natural sediments there was a pattern of increasing salinity with increasing elevation while in the sand-amended sediments the trend was reversed, showing decreasing salinity with increasing elevation. Sulfide concentrations generally increased from low to high inundation with highest concentrations at the highest inundation (i.e., at the lowest elevations. High pore water phosphate concentrations were measured at low elevations in the natural sediments, but the sand-amended treatments had mostly low concentrations of phosphate and no consistent pattern with elevation. At the end of the experiment the lowest elevations generally had the highest measures of pore water ammonium. Soil carbon dioxide emissions were greatest in the sand-amended mesocosms and at higher elevations. Differences in coarse root and rhizome abundances and volumes among the sediment treatments were detected with CT imaging, but by 20 weeks the natural and sand-amended treatments showed similar total belowground biomass at the intermediate and high elevations. Although differences in

New hybrid nanofluid containing encapsulated paraffin wax and sand nanoparticles in propylene glycol-water mixture: Potential heat transfer fluid for energy management

International Nuclear Information System (INIS)

Manikandan, S.; Rajan, K.S.

2017-01-01

Highlights: • Hybrid nanofluid containing sand nanoparticles & encapsulated paraffin wax prepared. • Specific heat of hybrid nanofluid 9% greater than that of PG-water mixture. • Specific heat & thermal conductivity enhanced at optimum paraffin wax concentration. • Hybrid nanofluid with 1 wt.% paraffin wax & 1 vol% sand nanoparticles best suited. - Abstract: The reduction in specific heat commonly encountered due to the addition of nanoparticles to a heat transfer fluid such as propylene glycol-water mixture, can be overcome by co-dispersing surfactant-encapsulated paraffin wax, leading to formation of a hybrid nanofluid. Experimental investigations have been carried out on the preparation and evaluation of thermophysical properties of a hybrid nanofluid containing pluronic P-123 encapsulated paraffin wax (70–120 nm diameter, 1–5 wt.%) and sand nanoparticles (1 vol%) in propylene glycol-water mixture. The comparison of results of differential scanning calorimetry of pure paraffin wax and encapsulated paraffin wax revealed encapsulation efficiency of 84.4%. The specific heat of hybrid nanofluids monotonously increased with paraffin wax concentration, with 9.1% enhancement in specific heat for hybrid nanofluid containing 5 wt.% paraffin wax, in comparison to propylene glycol-water mixture. There exists an optimum paraffin wax concentration (1 wt.%) for the hybrid nanofluid at which the combination of various thermophysical properties such as specific heat, thermal conductivity and viscosity are favorable for use as heat transfer fluid. Such a hybrid nanofluid can be used as a substitute for propylene glycol-water mixture in solar thermal systems.

Water Flow Investigation on Quartz Sand with 13-interval Stimulated Echo Multi Slice Imaging

Science.gov (United States)

Spindler, Natascha; Pohlmeier, Andreas; Galvosas, Petrik

2011-03-01

Understanding root water uptake in soils is of high importance for securing nutrition in the context of climate change and linked phenomena like stronger varying weather conditions (draught, strong rain). One step to understand how root water uptake occurs is the knowledge of the water flow in soil towards plant roots. Magnetic Resonance Imaging (MRI) in combination with q-space imaging is potentially the most powerful analytical tool for non-invasive three dimensional visualization of flow and transport in porous media. Numerous attempts have been made to measure local velocity in porous media by combining velocity phase encoding with fast imaging methods, where flow velocities in the vascular bundles of plant stems were investigated. In contrast to water situated in the cellular structure of plants, NMR signal arising from water in the pore space in soil may be much more affected by the presence of internal magnetic field gradients. In this work we account for the existence of these gradients by employing bipolar pulsed field magnetic gradients for velocity encoding. This enables one to study flow through sand (as a model system for soil) at flow rates relevant for the water uptake of plant roots.

Phosphate limitation in biological rapid sand filters used to remove ammonium from drinking water

DEFF Research Database (Denmark)

Lee, Carson Odell; Albrechtsen, Hans-Jørgen; Smets, Barth F.

2013-01-01

Removing ammonium from drinking water is important for maintaining biological stability in distribution systems. This is especially important in regions that do not use disinfectants in the treatment process or keep a disinfectant residual in the distribution system. Problems with nitrification c...... a pilot scale sand column which initial analysis confirmed performed similarly to the full scale filters. Long term increased ammonium loads were applied to the pilot filter both with and without phosphate addition. Phosphate was added at a concentration of 0.5 mg PO4-P/L to ensure...

Sand waves on an epicontinental shelf: Northern Bering Sea

Science.gov (United States)

Field, M.E.; Nelson, C.H.; Cacchione, D.A.; Drake, D.E.

1981-01-01

Sand waves and current ripples occupy the crests and flanks of a series of large linear sand ridges (20 km ?? 5 km ?? 10 m high) lying in an open-marine setting in the northern Bering Sea. The sand wave area, which lies west of Seward Peninsula and southeast of Bering Strait, is exposed to the strong continuous flow of coastal water northward toward Bering Strait. A hierarchy of three sizes of superimposed bedforms, all facing northward, was observed in successive cruises in 1976 and 1977. Large sand waves (height 2 m; spacing 200 m) have smaller sand waves (height 1 m; spacing 20 m) lying at a small oblique angle on their stoss slopes. The smaller sand waves in turn have linguoid ripples on their stoss slopes. Repeated studies of the sand wave fields were made both years with high-resolution seismic-reflection profiles, side-scan sonographs, underwater photographs, current-meter stations, vibracores, and suspended-sediment samplers. Comparison of seismic and side-scan data collected along profile lines run both years showed changes in sand wave shape that indicate significant bedload transport within the year. Gouge marks made in sediment by keels of floating ice also showed significantly different patterns each year, further documenting modification to the bottom by sediment transport. During calm sea conditions in 1977, underwater video and camera observations showed formation and active migration of linguoid and straight-crested current ripples. Current speeds 1 m above the bottom were between 20 and 30 cm/s. Maximum current velocities and sand wave migration apparently occur when strong southwesterly winds enhance the steady northerly flow of coastal water. Many cross-stratified sand bodies in the geologic record are interpreted as having formed in a tidal- or storm-dominated setting. This study provides an example of formation and migration of large bedforms by the interaction of storms with strong uniform coastal currents in an open-marine setting. ?? 1981.

Enabling technologies for oil sands development

International Nuclear Information System (INIS)

Bailey, R.T.

1998-01-01

A review of oil sands production and expansion possibilities in Alberta were presented. The enabling technologies for oil sands projects include mining (bucketwheels, draglines, trucks, shovels conveyors, slurry hydrotransport); extraction (conditioning tumblers, pipelines, tanks, hot water, caustic, cold water, frothers); froth cleaning (centrifuges, solvent treatment); tailings (tailings ponds, consolidated tailings); and upgrading (coking, hydrotreating for SCO, hydrocracking and multiple products). The enabling technologies for in situ production include cyclic steam stimulation for vertical wells, steam assisted gravity drainage (SAGD) for dual horizontal wells, and cold production with wormholes. This paper described the recovery potentials of each of these processes. It also discussed the role of government and industry in research and cooperative research involving both the private and public sectors. Examples of each of these were described such as SAGD, the OSLO cold water extraction process, The consolidated tailings (CT) project, the low energy extraction process (slurry production, hydrotransport, pipeline conditioning and warm water extraction), and research in fine tailings, to demonstrate that although objectives may differ, government and industry research objectives are complementary

Characteristics and Dynamics of a Large Sub-Tidal Sand Wave Field—Habitat for Pacific Sand Lance (Ammodytes personatus, Salish Sea, Washington, USA

Directory of Open Access Journals (Sweden)

H. Gary Greene

2017-10-01

Full Text Available Deep-water sand wave fields in the San Juan Archipelago of the Salish Sea and Pacific Northwest Washington, USA, have been found to harbor Pacific sand lance (PSL, Ammodytes personatus, a critical forage fish of the region. Little is known of the dynamics of these sand waves and the stability of the PSL sub-tidal habitats. Therefore, we have undertaken an initial investigation to determine the dynamic conditions of a well-known PSL habitat in the San Juan Channel within the Archipelago using bottom sediment sampling, an acoustical doppler current profiling (ADCP system, and multi-beam echo sounder (MBES bathymetry. Our study indicates that the San Juan Channel sand wave field maintained its shape and bedforms geometry throughout the years it has been studied. Based on bed phase diagrams for channelized bedforms, the sand waves appear to be in a dynamic equilibrium condition. Sea level rise may change the current regime within the Archipelago and may alter some of the deep-water or sub-tidal PSL habitats mapped there. Our findings have global significance in that these dynamic bedforms that harbor PSL and sand-eels elsewhere along the west coast of North America and in the North Sea may also be in a marginally dynamic equilibrium condition and may be prone to alteration by sea level rise, indicating an urgency in locating and investigating these habitats in order to sustain the forage fish.

Sand wave fields beneath the Loop Current, Gulf of Mexico: Reworking of fan sands

Science.gov (United States)

Kenyon, Neil H.; Akhmetzhanov, A.M.; Twichell, D.C.

2002-01-01

Extensive fields of large barchan-like sand waves and longitudinal sand ribbons have been mapped by deep-towed SeaMARC IA sidescan sonar on part of the middle and lower Mississippi Fan that lies in about 3200 m of water. The area is beneath the strongly flowing Loop Current. The bedforms have not been adequately sampled but probably consist of winnowed siliciclastic-foraminiferal sands. The size (about 200 m from wingtip to wingtip) and shape of the large barchans is consistent with a previously observed peak current speed of 30 cm/s, measured 25 m above the seabed. The types of small-scale bedforms and the scoured surfaces of chemical crusts, seen on nearby bottom photographs, indicate that near-bed currents in excess of 30 cm/s may sometimes occur. At the time of the survey the sand transport direction was to the northwest, in the opposite direction to the Loop Current but consistent with there being a deep boundary current along the foot of the Florida Escarpment. Some reworking of the underlying sandy turbidites and debris flow deposits is apparent on the sidescan sonar records. Reworking by deep-sea currents, resulting in erosion and in deposits characterised by coarsening upwards structures and cross-bedding, is a process that has been proposed for sand found in cores in shallower parts of the Gulf of Mexico. This process is more widespread than hitherto supposed. 

Oil sands naphthenic acids: a review of properties, measurement, and treatment.

Science.gov (United States)

Brown, Lisa D; Ulrich, Ania C

2015-05-01

The Alberta oil sands contain one of the world's largest reserves of oil - over 169 billion barrels of bitumen are economically recoverable with current extraction technologies. Surface mining and subsequent hot water extraction of bitumen from the ore generates about nine cubic meters of raw tailings per cubic meter of oil. Oil sands facilities are required to operate under a policy of zero water discharge, resulting in ponds containing more than one billion cubic meters of tailings, a mixture of sand, fines and process-affected water. Process-affected water contains numerous organic compounds, including naphthenic acids (NAs), which have been identified as the primary source of acute toxicity of process-affected water. Developments in analytical techniques, aerobic biodegradability, and treatment via chemical oxidation (ozone) of NAs are reviewed. The field continues to be challenged by the lack of a cost-effective, accurate analytical technique for NAs or an understanding of all the organic constituents in process-affected water that may be contributing to observed toxicity and thus requiring treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Selection of suitable fertilizer draw solute for a novel fertilizer-drawn forward osmosis-anaerobic membrane bioreactor hybrid system.

Science.gov (United States)

Kim, Youngjin; Chekli, Laura; Shim, Wang-Geun; Phuntsho, Sherub; Li, Sheng; Ghaffour, Noreddine; Leiknes, TorOve; Shon, Ho Kyong

2016-06-01

In this study, a protocol for selecting suitable fertilizer draw solute for anaerobic fertilizer-drawn forward osmosis membrane bioreactor (AnFDFOMBR) was proposed. Among eleven commercial fertilizer candidates, six fertilizers were screened further for their FO performance tests and evaluated in terms of water flux and reverse salt flux. Using selected fertilizers, bio-methane potential experiments were conducted to examine the effect of fertilizers on anaerobic activity due to reverse diffusion. Mono-ammonium phosphate (MAP) showed the highest biogas production while other fertilizers exhibited an inhibition effect on anaerobic activity with solute accumulation. Salt accumulation in the bioreactor was also simulated using mass balance simulation models. Results showed that ammonium sulfate and MAP were the most appropriate for AnFDFOMBR since they demonstrated less salt accumulation, relatively higher water flux, and higher dilution capacity of draw solution. Given toxicity of sulfate to anaerobic microorganisms, MAP appears to be the most suitable draw solution for AnFDFOMBR. Copyright © 2016 Elsevier Ltd. All rights reserved.

Selection of suitable fertilizer draw solute for a novel fertilizer-drawn forward osmosis-anaerobic membrane bioreactor hybrid system

KAUST Repository

Kim, Youngjin

2016-02-09

In this study, a protocol for selecting suitable fertilizer draw solute for anaerobic fertilizer-drawn forward osmosis membrane bioreactor (AnFDFOMBR) was proposed. Among eleven commercial fertilizer candidates, six fertilizers were screened further for their FO performance tests and evaluated in terms of water flux and reverse salt flux. Using selected fertilizers, bio-methane potential experiments were conducted to examine the effect of fertilizers on anaerobic activity due to reverse diffusion. Mono-ammonium phosphate (MAP) showed the highest biogas production while other fertilizers exhibited an inhibition effect on anaerobic activity with solute accumulation. Salt accumulation in the bioreactor was also simulated using mass balance simulation models. Results showed that ammonium sulphate and MAP were the most appropriate for AnFDFOMBR since they demonstrated less salt accumulation, relatively higher water flux, and higher dilution capacity of draw solution. Given toxicity of sulphate to anaerobic microorganisms, MAP appears to be the most suitable draw solution for AnFDFOMBR.

Permeability Tests on Eastern Scheldt Sand

DEFF Research Database (Denmark)

Jakobsen, Kim Parsberg

on the characteristics of the soil matrix, the permeability is determined for different void ratios. All tests are performed on reconstituted specimens of Eastern Scheldt Sand. The permeability is determined by use of a falling head apparatus. Finally the test results are briefly summarised and a relationship between......The flow through porous media plays an important role in various engineering disciplines, as for example in ground water hydrology and soil mechanics. In the present study the permeability is determined for a fine, saturated sand. As the flow through a porous media strongly depends...

Deep River Velocity and Sediment Profiles and the Suspended Sand Load,

Science.gov (United States)

1963-02-01

5.03 x IO~~ ATCHAFALAVA RIVER WIDTH : 1587 FT D 5, : 6.75 w 0 ~ FT SIMM ESPORT u : 6.66 FPS WATER TEMP. : 70 F d : 46.3 FT FINE SAND PORTION OP BED...1.34 * 10 3FT SIMM ESPORT ~ : 5.85 FPS WATCR TEMP. :69 ’F d : 47.7 FT FiNE SAND PORTION OP BED MATERIAL : 39.$ ~~ FIG. 16...DEC. 14,196 1 Q : 218,000 CF’S S : 336 *io ’~ ATCHAFALAVA RIVERWIDTH ?~ FPS WATER TEMP : løOx I0~~ FT SIMM ESPORT d : 4 1 .7 FT FINE SAND PORTION OF B

Directional optical transmission through a sand layer: a preliminary laboratory experiment

Science.gov (United States)

Tian, Jia; Philpot, William D.

2017-10-01

Given the importance of penetration of light in the soil for seed germination, soil warming, and the photolytic degradation of pesticides, directional transmission of thin sand samples are studied in this paper under both dry and saturated conditions. The detector views upward through a glass-bottom sample holder, filled to 3 or 4 mm with a coarse, translucent, quartz sand sample. Transmission through the samples was measured as the illumination zenith angle moved from 0 to 70° in 5° intervals. In the most cases, transmission decreased monotonically, but slowly with increasing illumination angle at all wavelengths. A peak in transmission only appeared at 0° illumination for the low bulk density, dry sample at 3 mm depth. The 0° peak disappeared when the sample was wetted, when the bulk density increased, or when the depth of the sample increased, which indicates that the radiation transmitting through a sand layer can be diffused thoroughly with a millimeters-thin sand layer. For the saturated samples, water influences light transmission in contrasting ways in shorter and longer wavelength. Transmission increased in the VNIR when saturated relative to dry, while transmission decreased sharply after 1300 nm, with spectral absorption features characteristic of water absorption. In VNIR region, water absorption is low and the low relative index of refraction enhanced transmission through sand sample. In contrast, water absorption became dominant at longer wavelengths region leading to the strongly reduced transmission.

Sediment Source Fingerprinting of the Lake Urmia Sand Dunes.

Science.gov (United States)

Ahmady-Birgani, Hesam; Agahi, Edris; Ahmadi, Seyed Javad; Erfanian, Mahdi

2018-01-09

Aeolian sand dunes are continuously being discovered in inner dry lands and coastal areas, most of which have been formed over the Last Glacial Maximum. Presently, due to some natural and anthropogenic implications on earth, newly-born sand dunes are quickly emerging. Lake Urmia, the world's second largest permanent hypersaline lake, has started shrinking, vast lands comprising sand dunes over the western shore of the lake have appeared and one question has been playing on the minds of nearby dwellers: where are these sand dunes coming from, What there was not 15 years ago!! In the present study, the determination of the source of the Lake Urmia sand dunes in terms of the quantifying relative contribution of each upstream geomorphological/lithological unit has been performed using geochemical fingerprinting techniques. The findings demonstrate that the alluvial and the fluvial sediments of the western upstream catchment have been transported by water erosion and they accumulated in the lower reaches of the Kahriz River. Wind erosion, as a secondary agent, have carried the aeolian sand-sized sediments to the sand dune area. Hence, the Lake Urmia sand dunes have been originating from simultaneous and joint actions of alluvial, fluvial and aeolian processes.

Alleviation of Water Stress Effects on MR220 Rice by Application of Periodical Water Stress and Potassium Fertilization

Directory of Open Access Journals (Sweden)

Nurul Amalina Mohd Zain

2014-02-01

Full Text Available The use of periodical water stress and potassium fertilization may enhance rice tolerance to drought stress and improve the crop’s instantaneous water use efficiency without much yield reduction. This study was conducted to assess the effects of different periodical water stress combined with potassium fertilization regimes on growth, yield, leaf gas exchanges and biochemical changes in rice grown in pots and compare them with standard local rice grower practices. Five treatments including (1 standard local grower’s practice (control, 80CF = 80 kg K2O/ha + control flooding; (2 120PW15 = 120 kg K2O/ha + periodical water stress for 15 days; (3 120DS15V = 120 kg K2O/ha + drought stress for 15 days during the vegetative stage; (4 120DS25V = 120 kg K2O/ha + drought stress for 25 days and (5 120DS15R = 120 kg K2O/ha + drought stress for 15 days during the reproductive stage, were evaluated in this experiment. Control and 120PW15 treatments were stopped at 100 DAS, and continuously saturated conditions were applied until harvest. It was found that rice under 120PW15 treatment showed tolerance to drought stress evidenced by increased water use efficiency, peroxidase (POX, catalase (CAT and proline levels, maximum efficiency of photosystem II (fv/fm and lower minimal fluorescence (fo, compared to other treatments. Path coefficient analysis revealed that most of parameters contribute directly rather than indirectly to rice yield. In this experiment, there were four factors that are directly involved with rice yield: grain soluble sugar, photosynthesis, water use efficiency and total chlorophyll content. The residual factors affecting rice yield are observed to be quite low in the experiment (0.350, confirming that rice yield was mostly influenced by the parameters measured during the study.

Total and methyl mercury concentrations in sediment and water of a constructed wetland in the Athabasca Oil Sands Region.

Science.gov (United States)

Oswald, Claire J; Carey, Sean K

2016-06-01

In the Athabasca Oil Sands Region in northeastern Alberta, Canada, oil sands operators are testing the feasibility of peatland construction on the post-mining landscape. In 2009, Syncrude Canada Ltd. began construction of the 52 ha Sandhill Fen pilot watershed, including a 15 ha, hydrologically managed fen peatland built on sand-capped soft oil sands tailings. An integral component of fen reclamation is post-construction monitoring of water quality, including salinity, fluvial carbon, and priority pollutant elements. In this study, the effects of fen reclamation and elevated sulfate levels on mercury (Hg) fate and transport in the constructed system were assessed. Total mercury (THg) and methylmercury (MeHg) concentrations in the fen sediment were lower than in two nearby natural fens, which may be due to the higher mineral content of the Sandhill Fen peat mix and/or a loss of Hg through evasion during the peat harvesting, stockpiling and placement processes. Porewater MeHg concentrations in the Sandhill Fen typically did not exceed 1.0 ng L(-1). The low MeHg concentrations may be a result of elevated porewater sulfate concentrations (mean 346 mg L(-1)) and an increase in sulphide concentrations with depth in the peat, which are known to suppress MeHg production. Total Hg and MeHg concentrations increased during a controlled mid-summer flooding event where the water table rose above the ground surface in most of the fen. The Hg dynamics during this event showed that hydrologic fluctuations in this system exacerbate the release of THg and MeHg downstream. In addition, the elevated SO4(2-) concentrations in the peat porewaters may become a problem with respect to downstream MeHg production once the fen is hydrologically connected to a larger wetland network that is currently being constructed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Practical technical solution for clay-contaminated sands used in concrete

Directory of Open Access Journals (Sweden)

Estephane Pierre

2017-01-01

Full Text Available Sand, whether natural or manufactured, shows in many instances varying degrees of high levels of clay contamination. This fact is encountered in different parts of the globe and can lead to serious problems in adjusting concrete mix proportions and requiring high water to cement ratios and/or high dosages of superplasticizers without necessarily meeting the workability requirements, even when the sand is previously washed with fresh water. In this paper, different types of sand from the Gulf Cooperation Council (GCC region are being screened, analysed for their clay contents and consequent effects on plastic concrete quality. A technical solution is being proposed based on engineered superplasticizers. A testing protocol has been established to verify the robustness of optimized mix designs demonstrating the performance of the admixture in terms of initial and extended workability. In particular, it will be demonstrated that the customized concrete admixtures constitute by themselves a stand-alone answer to the usage of clay-contaminated sands in concrete.

Canada's oil sands : opportunities and challenges to 2015 : an update

International Nuclear Information System (INIS)

2006-06-01

This report updated an energy market assessment compiled and published by the National Energy Board (NEB) in 2004. Major changes resulting from recent developments in the oil sands industry were presented. The report was compiled from a series of informal meetings and discussions with a cross-section of oil sands stakeholders. Influences on recent oil sands development and production growth included market development and pipelines; rising capital and labour costs; operating costs; environmental impact management; high crude oil prices; rising global energy demand; technology innovations; and a more stable investment climate. A comparison of key assumptions between the current analysis and the 2004 report was presented, along with estimates of operating and supply costs for various types of oil sands recovery methods. Potential markets for oil sands production were reviewed. Environmental and socio-economic impacts on the industry included the larger than anticipated water withdrawals from the Athabasca River for mining operations; and uncertainties over land reclamation methods. The industry has also been impacted by a limited supply of skilled workers in Alberta. It was observed that the potential for building cogeneration capacity has decreased since the 2004 report. It was concluded that the oil sands industry will continue to grow rapidly, but the rate of development will depend on the balance that is reached between the opposing forces that affect the oil sands. Natural gas costs, high oil prices, air emissions management issues and water usage will continue to be of concern. 6 tabs., 7 figs

Agriculture: Nutrient Management and Fertilizer

Science.gov (United States)

Fertilizers and soil amendments can be derived from raw materials, composts and other organic matter, and wastes, such as sewage sludge and certain industrial wastes. Overuse of fertilizers can result in contamination of surface water and groundwater.

Evaluation of fertilizer-drawn forward osmosis for sustainable agriculture and water reuse in arid regions

KAUST Repository

Chekli, Laura; Kim, Youngjin; Phuntsho, Sherub; Li, Sheng; Ghaffour, NorEddine; Leiknes, TorOve; Shon, Ho Kyong

2016-01-01

to determine the effect of osmotic concentration of wastewater achieved in the FDFO process on the anaerobic activity. Results showed that 95% water recovery from the FDFO process is the optimum value for further AnMBR treatment. Nine different fertilizers were

Effective integration between heavy water plant and fertilizer plant for higher production of heavy water (D2O) (Preprint No. PD-10)

International Nuclear Information System (INIS)

Periakaruppan, M.; Gupta, S.K.; Bhowmick, S.C.

1989-04-01

For smooth and efficient running of heavy water plants linked with fertilize r plants, it is necessary that certain factors must be taken into consideration right from the design stage of a fertilizer plant. These factors are: (1)preventing loss in D 2 concentration in syn gas, (2)keeping the level of CO 2 and CO in syn gas below 1 ppm, (3)operating the ammonia plant at highest pressure and (4)keeping the feed gas ammonia supply available without any interruption. Incorporation of these factors in the design is discussed. (M.G.B. )

Advanced characterisation of organic matter in oil sands and tailings sands used for land reclamation by Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS)

Science.gov (United States)

Noah, M.; Vieth-Hillebrand, A.; Wilkes, H.

2012-04-01

The Athabasca region of northern Alberta, Canada, is home to deposits of oil sands containing vast amounts (~ 173 billion barrels) of heavily biodegraded petroleum. Oil sands are recovered by surface mining or by in situ steam injection. The extraction of bitumen from oil sands by caustic hot water processing results in large volumes of fluid tailings, which are stored in on-site settling basins. There the tailings undergo a compaction and dewatering process, producing a slowly densifying suspension. The released water is recycled for extraction. The fine tailings will be reclaimed as either dry or wet landscapes. [1] To produce 1 barrel of crude oil, 2 tons of oil sand and 2 - 3 tons of water (including recycled water) are required. [2] Open pit mining and the extraction of the bitumen from the oil sands create large and intense disturbances of different landscapes. The area currently disturbed by mining operations covers about 530 km2 and the area of tailing ponds surpasses 130 km2. An issue of increasing importance is the land remediation and reclamation of oil sand areas in Canada and the reconstruction of these disturbed landscapes back to working ecosystems similar to those existing prior to mining operations. An important issue in this context is the identification of oil sand-derived organic compounds in the tailings, their environmental behaviour and the resulting chances and limitations with respect to land reclamation. Furthermore the biodegradation processes that occur in the tailings and that could lead to a decrease in hazardous organic compounds are important challenges, which need to be investigated. This presentation will give a detailed overview of our compositional and quantitative characterisation of the organic matter in oil sand, unprocessed and processed mature fine tailings samples as well as in tailings sands used as part of land reclamation. The analytical characterisation is based on the extraction of the soluble organic matter, its

The use of stable isotopes to trace oil sands constituents

International Nuclear Information System (INIS)

Farwell, A.J.; Nero, V.; Dixon, D.G.

2002-01-01

A study was conducted to determine the biological effects of oil sands mining operations on aquatic ecosystems. The study focused on the Athabasca oil sand deposit, the largest of 4 deposits in northern Alberta. In particular, the study examined the cycling of oil sand constituents in Benthic invertebrates collected from test pits at Syncrude Canada Ltd.. The invertebrates were similar in size, but different in the quantity of process-affected water or mature fine tailings containing residual bitumen. Dragonflies and damselflies in particular, showed trends of depletion for the carbon 13 isotope and enrichment in nitrogen 15 isotope in pits where levels of process affected water was high. The depletion of carbon 13 isotope suggests that oil sand constituents assimilate into the benthic food chain. The greatest carbon 13 depletion, which was approximately 27 per cent, was found to be in test pits with high turbidity. This implies that oil sands constituents degrade microbially instead of by photosynthetic production. All benthic invertebrate group demonstrated an incremental enrichment in nitrogen 15 isotope from the control pit to the pit with greatest levels of mature fine tailings

Intermontane eolian sand sheet development, Upper Tulum Valley, central-western Argentina

Directory of Open Access Journals (Sweden)

Patrick Francisco Fuhr Dal' Bó

Full Text Available ABSTRACTThe intermontane Upper Tulum eolian sand sheet covers an area of ca. 125 km² at north of the San Juan Province, central-western Argentina. The sand sheet is currently an aggrading system where vegetation cover, surface cementation and periodic flooding withhold the development of dunes with slipfaces. The sand sheet surface is divided into three parts according to the distribution of sedimentary features, which reflects the variation in sediment budget, water table level and periodic flooding. The central sand sheet part is the main area of eolian deposition and is largely stabilized by vegetation. The sedimentary succession is 4 m thick and records the vertical interbedding of eolian and subaqueous deposits, which have been deposited for at least 3.6 ky with sedimentation rates of 86.1 cm/ky. The construction of the sand sheet is associated with deflation of the sand-graded debris sourced by San Juan alluvial fan, which is available mainly in drier fall-winter months where water table is lower and wind speeds are periodically above the threshold velocity for sand transport. The accumulation of sedimentary bodies occurs in a stabilized eolian system where vegetation cover, thin mud veneers and surface cementation are the main agents in promoting accumulation. The preservation of the sand sheet accumulations is enabled by the progressive creation of the accommodation space in a tectonically active basin and the continuous burial of geological bodies favored by high rates of sedimentation.

Effect of Gamma Irradiation on Polymer Modified White Sand Cement Mortar Composites

International Nuclear Information System (INIS)

Khattab, M.M.

2012-01-01

This study focuses on the substitution effect of standard sand of conventional cement mortar made from ordinary Portland cement (OPC) and standard sand (SS) OPC/SS 1:3; by different ratios of white sand (WS) powder to prepare three types of white sand cement mortar designated as 1OPC:2SS:1WS, 1OPC:1SS:2WS and 1OPC:0SS:3WS. The prepared samples were first cured under tap water for different time intervals namely 3, 7, 28 and 90 days. The effect of addition of 10% styrene-acrylic ester (SAE) as well as the effect of different doses of gamma rays (10, 20, 30 and 50 kGy) on the physicomechanical properties of polymer modified white sand cement mortar specimens also discussed. Compression strength test, total porosity and water absorption percentages were measured according to standard specifications. The obtained data indicated that, the cement mortar samples containing different ratios of white sand have lower values of compressive strength as compared to the conventional cement mortar while, the percentages of total porosity and water absorption increased. On the other hand, the polymer modified mortar specimens showed a noticeably enhancement in the physico-mechanical properties under the effect of gamma-radiation than those of untreated samples. These results were confirmed by scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) studies

Environmental protection foliar fertilization in areas subject to limitation of fertilizers use

International Nuclear Information System (INIS)

Gavriluta, I.; Alexandrescu, A; Budoi, G.; Bireescu, L.; Bireescu, G.

1999-01-01

Significant increases of plant productivity have been recorded in field experiments conducted between 1991 - 1994 using general purpose complex foliar fertilizers as well as aminoacid containing complex foliar fertilizers. These increases at the same time had positive environmental effects against chemical pollution, especially with nitrates. As a rule, the greater the degree of nutrient efficiency, especially of nitrate, the lower are the losses, which are subject to transfer to the environment. So in the light of environmental protection against chemical pollution using foliar fertilization is certainly beneficial for crops and for all other components of the agricultural environment giving rise to its significant improvement. Both, foliar and soil fertilization in areas with limitation of fertilizer use should be carried out under a continuous and strict analytical check of plant, soil and water. Refs. 14 (author)

Preparation and characterization of poly(acrylic acid)—corn starch blend for use as chemical sand-fixing materials

Science.gov (United States)

Dang, Xugang; Chen, Hui; Shan, Zhihua

2017-07-01

One chemical sand-fixing materials based on poly(acrylic acid)-corn starch (PACS) blend was studied in this work. The PACS blend was prepared by solution mixing method between PA and CS. In order to prepare sand-fixing materials for environmental applications using the well-established method of spraying evenly PACS blend solution on the surfaces of fine sand. Fourier transform infrared spectroscopy (FT-IR) revealed the existence of the intermolecular interactions between the blend components. Scanning electron microscope (SEM) analysis showed a continuous phase of blend, and it also showed the good sand-fixing capacity. The test results of hygroscopicity and water retention experiments indicated that the blends had excellent water-absorbing and water-retention capacity. The results of contact angle measurements between the PACS solutions and fine sand showed that the PACS blend has a satisfactory effect on fine sand wetting. And the PACS, as a sand-fixation material, has excellent sand-fixation rate up to 99.5%.

Nano sand filter with functionalized nanoparticles embedded in anodic aluminum oxide templates

OpenAIRE

Phuong, NguyenThi; Andisetiawan, Anugrah; Van Lam, Do; Kim, Jeong Hwan; Choi, Doo-Sun; Whang, Kyung-Hyun; Nham, Jeasun; Lee, Yun Jung; Yoo, Yeong-Eun; Yoon, Jae Sung

2016-01-01

Since the ancient Egyptians had used sand as filter media for water purification, its principle has been inherited through generations and it is still being used now in industries. The sand filter consists of sand literally, and the voids within the sand bed are the pores for filtration. Here we present a filtration principle using nanoparticles, so that the voids between the nanoparticles can be considered as effective pores in nanoscale dimension. Anodic aluminum oxide (AAO) membrane has be...

Effectiveness of SCADA Systems in Control of Green Sands Properties

Directory of Open Access Journals (Sweden)

Ignaszak Z.

2016-03-01

Full Text Available The paper undertakes an important topic of evaluation of effectiveness of SCADA (Supervisory Control and Data Acquisition systems, used for monitoring and control of selected processing parameters of classic green sands used in foundry. Main focus was put on process studies of properties of so-called 1st generation molding sands in the respect of their preparation process. Possible methods of control of this processing are presented, with consideration of application of fresh raw materials, return sand (regenerate and water. The studies conducted in one of European foundries were aimed at pointing out how much application of new, automated plant of sand processing incorporating the SCADA systems allows stabilizing results of measurement of selected sand parameters after its mixing. The studies concerned two comparative periods of time, before an implementation of the automated devices for green sands processing (ASMS - Automatic Sand Measurement System and MCM – Main Control Module and after the implementation. Results of measurement of selected sand properties after implementation of the ASMS were also evaluated and compared with testing studies conducted periodically in laboratory.

Pesticide and transformation product detections and age-dating relations from till and sand deposits

Science.gov (United States)

Warner, K.L.; Morrow, W.S.

2007-01-01

Pesticide and transformation product concentrations and frequencies in ground water from areas of similar crop and pesticide applications may vary substantially with differing lithologies. Pesticide analysis data for atrazine, metolachlor, alachlor, acetochlor, and cyanazine and their pesticide transformation products were collected at 69 monitoring wells in Illinois and northern Indiana to document occurrence of pesticides and their transformation products in two agricultural areas of differing lithologies, till, and sand. The till is primarily tile drained and has preferential fractured flow, whereas the sand primarily has surface water drainage and primary porosity flow. Transformation products represent most of the agricultural pesticides in ground water regardless of aquifer material - till or sand. Transformation products were detected more frequently than parent pesticides in both the till and sand, with metolachlor ethane sulfonic acid being most frequently detected. Estimated ground-water recharge dates for the sand were based on chlorofluorocarbon analyses. These age-dating data indicate that ground water recharged prior to 1990 is more likely to have a detection of a pesticide or pesticide transformation product. Detections were twice as frequent in ground water recharged prior to 1990 (82%) than in ground water recharged on or after 1990 (33%). The highest concentrations of atrazine, alachlor, metolachlor, and their transformation products, also were detected in samples from ground water recharged prior to 1990. These age/pesticide detection relations are opposite of what would normally be expected, and may be the result of preferential flow and/or ground-water mixing between aquifers and aquitards as evident by the detection of acetochlor transformation products in samples with estimated ground-water ages predating initial pesticide application. ?? 2007 American Water Resources Association.

A hybrid froth flotation-filtration system as a pretreatment for oil sands tailings pond recycle water management: Bench- and pilot-scale studies.

Science.gov (United States)

Loganathan, Kavithaa; Bromley, David; Chelme-Ayala, Pamela; Gamal El-Din, Mohamed

2015-09-15

Through sustainable water management, oil sands companies are working to reduce their reliance on fresh water by minimizing the amount of water required for their operations and by recycling water from tailings ponds. This study was the first pilot-scale testing of a hybrid technology consisting of froth flotation combined with filtration through precoated submerged stainless steel membranes used to treat recycle water from an oil sands facility. The results indicated that the most important factor affecting the performance of the hybrid system was the influent water quality. Any rise in the levels of suspended solids or total organic carbon of the feed water resulted in changes of chemical consumption rates, flux rates, and operating cycle durations. The selections of chemical type and dosing rates were critical in achieving optimal performance. In particular, the froth application rate heavily affected the overall recovery of the hybrid system as well as the performance of the flotation process. Optimum surfactant usage to generate froth (per liter of treated water) was 0.25 mL/L at approximately 2000 NTU of influent turbidity and 0.015 mL/L at approximately 200 NTU of influent turbidity. At the tested conditions, the optimal coagulant dose was 80 mg/L (as Al) at approximately 2000 NTU of influent turbidity and recycle water. Copyright © 2015 Elsevier Ltd. All rights reserved.

Interactions between microbial activity and distribution and mineral coatings on sand grains from rapid sand filters treating groundwater

DEFF Research Database (Denmark)

Gülay, Arda; Tatari, Karolina; Musovic, Sanin

Rapid sand filtration is a traditional and widespread technology for drinking water purification which combines biological, chemical and physical processes together. Granular media, especially sand, is a common filter material that allows several oxidized compounds to accumulate on its surface....... Preliminarily, we detected a strong relation between the amount of DNA and mineral coating mass. We hypothesized that the accumulated mineral coatings have a positive effect on amount of bacterial biomass, its spatial distribution and substrate removal rates. In this study, we combined molecular, microscopic...

The Suitability Of Local Quartz Sand In The Production Of Bath Crucibles.

Directory of Open Access Journals (Sweden)

C. O. Okpanachi

2017-03-01

Full Text Available The suitability of local quartz sand in the production of bath crucibles is a study that was carried out in order to impart overall strength on bath crucibles hence reduce breakages during fettling. Therefore this research constitutes a study to enhance the efficiency of production of bath crucibles by addition of quartz sand in slip preparation. The steps taken in the beneficiation of quartz sand for the production of bath crucibles are comminution which entails crushing and milling classification washing liquid dispersion sizing and reduction of iron content by magnetic separation. The slip contains materials like plastic clay feldspar kaolin talc sodium silicate water quartz sand etc. These were all milled in the ball mill for slip production casting and fettling glazing and sintering to get final bath crucibles as the end products. Quartz sand is used in a variety of products essentially as raw material for the foundry casting and glass industries and also in chemicals water filtration and ceramics the heat resistance nature of quartz sand makes it an excellent refractory substance for these industrial processes. Slip can be prepared for production of bath crucibles without the inclusion of quartz sand however the addition of quartz sand is needed to improve the mechanical performance of the slip in the production of bath crucibles.

Laboratory studies of dune sand for the use of construction industry in Sri Lanka

Science.gov (United States)

de Silva Jayawardena, Upali; Wijesuriya, Roshan; Abayaweera, Gayan; Viduranga, Tharaka

2015-04-01

With the increase of the annual sand demand for the construction industry the excessive excavation of river sand is becoming a serious environmental problem in Sri Lanka. Therefore, it is necessary to explore the possibility for an alternative to stop or at least to minimize river sand mining activities. Dune sand is one of the available alternative materials to be considered instead of river sand in the country. Large quantities of sand dunes occur mainly along the NW and SE coastal belt which belong to very low rainfall Dry Zone coasts. The height of dune deposits, vary from 1m to about 30 meters above sea level. The objective of this paper is to indicate some studies and facts on the dune sand deposits of Sri Lanka. Laboratory studies were carried out for visual observations and physical properties at the initial stage and then a number of tests were carried out according to ASTM standards to obtain the compressive strength of concrete cylinders and mortar cubes mixing dune sand and river sand in different percentages keeping a constant water cement ratio. Next the water cement ratio was changed for constant dune sand and river sand proportion. Microscopic analysis shows that the dune sand consist of 95 % of quartz and 5 % of garnet, feldspar, illmenite and other heavy minerals with clay, fine dust, fine shell fragments and organic matters. Grains are sub-rounded to angular and tabular shapes. The grain sizes vary from fine to medium size of sand with silt. The degree of sorting and particle size observed with dune sands are more suited with the requirement of fine aggregates in the construction industry. The test result indicates that dune sand could be effectively used in construction work without sieving and it is ideal for wall plastering due to its'-uniformity. It could also be effectively used in concrete and in mortars mixing with river sand. The best mixing ratio is 75% dune sand and 25% river sand as the fine aggregate of concrete. For mortar the mixing

Bedding and Fertilization Influence on Slash Pine Development in the Florida Sandhills

Science.gov (United States)

James B. Baker

1973-01-01

A field study on the infertile and droughty Lakeland sands of west Florida indicated that bedding or fertilization (134 kg P /ha as ordinary superphosphate and 90 kg N/ha as ammonium nitrate) or both increased early growth of planted slash pine ( Engelm.). Throughout the 6-year study, best growth was obtained when the treatments were...

Observation of sand waves in the Taiwan Banks using HJ-1A/1B sun glitter imagery

Science.gov (United States)

Zhang, Hua-guo; Lou, Xiu-lin; Shi, Ai-qin; He, Xie-kai; Guan, Wei-bing; Li, Dong-ling

2014-01-01

This study focuses on the large sand waves in the Taiwan Banks. Our goals are to observe the sand waves as completely as possible, to obtain their direction, wavelength, density, and ridge length, to analyze their spatial distributions, and to understand the effects of the current field and water depth on the sand waves. This study demonstrates the possibility of using HJ-1A/1B sun glitter imagery with a large swath width and rapid coverage in studying sand waves. Six cloud-free HJ-1A/1B optical images with sun glitter signals received during 2009 to 2011 were processed. The sand waves were mapped based on their features in the images; their direction, wavelength, density, and ridge length were measured and analyzed. We identified 4604 sand waves distributed in an area of 16,400 km2. The distributions of sand waves and their characteristics were analyzed, and the differences of sand waves between the northwestern subregion and the southeastern subregion are reported. Further analysis and discussion of the relationships between spatial distribution of the sand waves and both the tidal current field from a numerical simulation and water depth led to some interesting conclusions. The current field determines the orientation of the sand wave, while the hydrodynamic conditions and water depth influence the shape, size, and density of sand waves to a certain degree.

Sand transportation and reverse patterns over leeward face of sand dune

Science.gov (United States)

Jiang, Hong; Dun, Hongchao; Tong, Ding; Huang, Ning

2017-04-01

Sand saltation has complex interactions with turbulent flow and dune form. Most models of wind-blown sand consider ideal circumstances such as steady wind velocity and a flat surface, and the bulk of data on wind flow and sand transport over an individual dune has focused mostly on the influence of dune shape or inter-dune space on the wind flow, neglecting the effect of morphology on sand saltation, particularly airflow and sand transportation over the leeward slope. Wind flow structures over the leeward slope of sand dunes have a fundamental influence on the organization of sand dunes. In order to understand sand dune dynamics, lee face airflow and sediment transportation should be paid more attention. Previous field observations could not measure turbulent flow structure well because of the limited observation points and the influence of experiment structure on wind field. In addition, the reverse sand particles over leeward face could not be collected by sand trap in field. Numerous field observations could not measure turbulent flow structure because of the limited observation points and the influence of experimental structures on the wind field. In addition, the reverse transport of sand particles over leeward face could not be collected by sand traps in field. Therefore, this paper aims to investigate the turbulent flow structure and sand transport pattern over the leeward slope. A numerical model of sand saltation over slope terrain is constructed, which also considers the coupling effects between air flow and sand particles. The large eddy simulation method is used to model turbulent flow. Sand transport is simulated by tracking the trajectory of each sand particle. The results show that terrain significantly alters the turbulent air flow structure and wind-blown sand movement, especially over the leeward slope. Here, mass flux increases initially and then decreases with height in the reversed flow region in the direction of wind flow, and the mass flux

Sulphur output from oil sands : dramatically changing Alberta's sulphur balance

Energy Technology Data Exchange (ETDEWEB)

D' Aquin, G. [Con-Sul Inc., Bigfork, MT (United States)

2008-07-01

This paper discussed sulphur production from Alberta's gas and oil sands industries. While sulfur derived from natural gas production in the province is expected to decline as natural gas reserves diminish, Alberta's oil sands contain high amounts of sulphur. It is not yet known how much sulphur will be produced from the province's oil sands facilities. Alberta had considerable stockpiles of sulphur in the 1970s. By 1980, inventories began to decline. By 1996, output had increased to 7.1 million tonnes. Alberta's sulphur inventory reached 9.7 million tonnes following the collapse of the Soviet Union's government mandated fertilizer industry. In 2006, sulphur supplies in Alberta reached 12 million tonnes. Reduced global output has now lowered sulphur stockpiles. Increases in sulphur prices tend to reduce market demand, and lower prices will not typically change the volume of sulphur produced as a byproduct of oil and gas operations. Bitumen-derived sulphur output is expected to exceed gas-derived sulphur output in the near future. Sulphur from oil sands processing is expected to increase by 5 million tonnes by 2017. Increased sulphur production levels in Alberta will present a significant challenge for all sectors of the hydrocarbon industry. It was concluded that developing a plan for storing, selling or disposing of the sulphur will help to ensure the profitability of oil sands operations.

Slow-release NPK fertilizer encapsulated by carboxymethyl cellulose-based nanocomposite with the function of water retention in soil.

Science.gov (United States)

Olad, Ali; Zebhi, Hamid; Salari, Dariush; Mirmohseni, Abdolreza; Reyhani Tabar, Adel

2018-09-01

In this study, new slow release fertilizer encapsulated by superabsorbent nanocomposite was prepared by in-situ graft polymerization of sulfonated-carboxymethyl cellulose (SCMC) with acrylic acid (AA) in the presence of polyvinylpyrrolidone (PVP), silica nanoparticles and nitrogen (N), phosphorous (P), and potassium (K) (NPK) fertilizer compound. The prepared materials were characterized by FT-IR, XRD and scanning electron microscopy (SEM) techniques. The incorporation of NPK fertilizer into hydrogel nanocomposite network was verified by results of these analyses. Also, the swelling behavior in various pH and saline solutions as well as water retention capability of the prepared hydrogel nanocomposite was evaluated. The fertilizer release behavior of the NPK loaded hydrogel nanocomposite was in good agreement with the standard of Committee of European Normalization (CEN), indicating its excellent slow release property. These good characteristics revealed that the hydrogel nanocomposite fertilizer formulation can be practically used in agricultural and horticultural applications. Copyright © 2018 Elsevier B.V. All rights reserved.

The Geodiversity in Drift Sand Landscapes of The Netherlands

Science.gov (United States)

van den Ancker, Hanneke; Jungerius, Pieter Dirk; Riksen, Michel

2015-04-01

The authors carried out detailed field studies of more than twelve drift sand landscapes in The Netherlands. The objective of these studies was to restore Natura-2000 values by restoring the wind activity. Active drift sands occur almost exclusively in The Netherlands, Natura 2000 habitat 2330 'Inland dunes with open Corynephorus and Agrostis grasslands', for which reason our country is largely responsible for this European landscape. Active drift sands had almost disappeared for two reasons: first, the stabilization of the drift sands by air pollution, mainly nitrogen, which stimulates the growth of algae and grasses that initiate soil formation, and second, by the growth of forests surrounding the sands, which decreases the wind force. The restoration studies revealed differences in the geodiversity between and within the drift sand areas. Whereas the drift sands on geological and soil maps show as almost homogenous areas, they have in fact highly variable geo-conditions of which examples will be given. These geodiversity aspects concern differences in geomorphological structure, origin, sediments and age of the drift sands. Differences in wind and water erosion, trampling and soil formation add to the geodiversity within the drift sand areas. Especially in the primary stages of succession the differences in geodiversity are relevant for the Natura-2000 values. We discerned three main types of active sands. Firstly, the impressive drift sands with large parabolic dune structures, often consisting of series of interlocking parabolic dunes. They developed from the northeast towards the southwest, against the direction of the dominant wind, and must have taken centuries to develop. Small parts of these systems are still active, other parts show different degrees of soil formation. Their origin is still unclear but probably dates from medieval times (Heidinga, 1985, Jungerius & Riksen, 2008). Second are the drift sand areas with irregular hills from 0.5 to about 2

Experimental investigation on heat transport in gravel-sand materials

DEFF Research Database (Denmark)

Maureschat, Gerald; Heller, Alfred

1997-01-01

in sand-gravel material, the storage media is to be water satured. In this case, handling of such material on site is rather complex. The conduction is highly dependent on the thermal properties of the storage media and so is the overall thermal performance of a storage applying such media. For sandy...... out in a small size experiment. The experiment consists of a highly insulated box filled with two kinds of sand material crossed by a plastic heat pipe. Heat transfer is measured under dry and water satured conditions in a cross-section.The conclusions are clear. To obtain necessary heat conduction...

Comparison of plasma generated nitrogen fertilizer to conventional fertilizers ammonium nitrate and sodium nitrate for pre-emergent and seedling growth

Science.gov (United States)

Andhavarapu, A.; King, W.; Lindsay, A.; Byrns, B.; Knappe, D.; Fonteno, W.; Shannon, S.

2014-10-01

Plasma source generated nitrogen fertilizer is compared to conventional nitrogen fertilizers in water for plant growth. Root, shoot sizes, and weights are used to examine differences between plant treatment groups. With a simple coaxial structure creating a large-volume atmospheric glow discharge, a 162 MHz generator drives the air plasma. The VHF plasma source emits a steady state glow; the high drive frequency is believed to inhibit the glow-to-arc transition for non-thermal discharge generation. To create the plasma activated water (PAW) solutions used for plant treatment, the discharge is held over distilled water until a 100 ppm nitrate aqueous concentration is achieved. The discharge is used to incorporate nitrogen species into aqueous solution, which is used to fertilize radishes, marigolds, and tomatoes. In a four week experiment, these plants are watered with four different solutions: tap water, dissolved ammonium nitrate DI water, dissolved sodium nitrate DI water, and PAW. Ammonium nitrate solution has the same amount of total nitrogen as PAW; sodium nitrate solution has the same amount of nitrate as PAW. T-tests are used to determine statistical significance in plant group growth differences. PAW fertilization chemical mechanisms are presented.

Advanced characterisation of organic matter in oil sands and tailings sands used for land reclamation by Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS).

OpenAIRE

Mareike Noah; Andrea Vieth-Hillebrand; Heinz Wilkes

2012-01-01

The Athabasca region of northern Alberta, Canada, is home to deposits of oil sands containing vast amounts (~ 173 billion barrels) of heavily biodegraded petroleum. Oil sands are recovered by surface mining or by in situ steam injection. The extraction of bitumen from oil sands by caustic hot water processing results in large volumes of fluid tailings, which are stored in on-site settling basins. There the tailings undergo a compaction and dewatering process, producing a slowly densifying sus...

Proceedings of the 2. international oil sands tailings conference

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

The tailings produced by oil sands extraction processes pose significant threats to the surrounding environment in addition to releasing greenhouse gases (GHGs) into the atmosphere. Recent directives have been established to reduce the amount of tailings produced at oil sands operations, and to ensure that tailings ponds are reclaimed in the most effective manner. This conference provided a forum for researchers and industry experts to discuss issues related to the management and reclamation of oil sands tailings. New technologies for dewatering tailings ponds were presented, and methods of analyzing the chemical properties of tailings were reviewed. The conference was divided into the following 7 sessions: (1) tailings properties, (2) tailings dewatering, (3) new concepts, (4) water and chemistry, (5) soft tailings stabilization and reclamation, (6) water treatment, and (7) new concepts 2. The conference featured 44 presentations, all of which have been catalogued separately for inclusion in this database. tabs., figs.

Fertilizing Douglas-fir forests.

Science.gov (United States)

Richard E. Miller; Roger D. Right

1979-01-01

This report supplements a slide-tape presentation of the same title. Part I of the report describes the current practice of nitrogen fertilization of Douglas-fir forests in western Washington and Oregon and the effects of this fertilization on tree growth and water quality. Part II discusses factors that affect costs and revenues from investments in forest...

The extraction of bitumen from western oil sands

International Nuclear Information System (INIS)

Oblad, A.G.; Bunger, J.W.; Dahlstrom, D.A.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

1992-08-01

The University of Utah tar sand research and development program is concerned with research and development on Utah is extensive oil sands deposits. The program has been intended to develop a scientific and technological base required for eventual commercial recovery of the heavy oils from oil sands and processing these oils to produce synthetic crude oil and other products such as asphalt. The overall program is based on mining the oil sand, processing the mined sand to recover the heavy oils and upgrading them to products. Multiple deposits are being investigated since it is believed that a large scale (approximately 20,000 bbl/day) plant would require the use of resources from more than one deposit. The tasks or projects in the program are organized according to the following classification: Recovery technologies which includes thermal recovery methods, water extraction methods, and solvent extraction methods; upgrading and processing technologies which covers hydrotreating, hydrocracking, and hydropyrolysis; solvent extraction; production of specialty products; and environmental aspects of the production and processing technologies. These tasks are covered in this report

[Fine root dynamics and its relationship with soil fertility in tropical rainforests of Chocó].

Science.gov (United States)

Quinto, Harley; Caicedo, Haylin; Thelis Perez, May; Moreno, Flavio

2016-12-01

The fine roots play an important role in the acquisition of water and minerals from the soil, the global carbon balance and mitigation of climate change. The dynamics (productivity and turnover) of fine roots is essential for nutrient cycling and carbon balance of forest ecosystems. The availability of soil water and nutrients has significantly determined the productivity and turnover of fine roots. It has been hypothesized that fine roots dynamics increases with the availability of soil resources in tropical forest ecosystems. To test this hypothesis in tropical rainforests of Chocó (ecosystems with the highest rainfall in the world), five one-ha permanent plots were established in the localities of Opogodó and Pacurita, where the productivity and turnover of fine roots were measured at 0-10 cm and 10-20 cm depth. The measurement of the fine root production was realized by the Ingrowth core method. The fine root turnover was measured like fine roots production divided mean annual biomass. In addition, soil fertility parameters (pH, nutrients, and texture) were measured and their association with productivity and turnover of fine roots was evaluated. It was found that the sites had nutrient-poor soils. The localities also differ in soil; Opogodó has sandy soils and flat topography, and Pacurita has clay soils, rich in aluminum and mountainous topography. In Opogodó fine root production was 6.50 ± 2.62 t/ha.yr (mean ± SD). In Pacurita, fine root production was 3.61 ± 0.88 t/ha.yr. Also in Opogodó, the fine root turnover was higher than in Pacurita (1.17 /y and 0.62 /y, respectively). Fine root turnover and production in the upper soil layers (10 cm upper soil) was considerably higher. Productivity and turnover of fine roots showed positive correlation with pH and contents of organic matter, total N, K, Mg, and sand; whereas correlations were negative with ECEC and contents of Al, silt, and clay. The percentage of sand was the parameter that best explained

Arsenic uptake and accumulation in rice (Oryza sativa L.) with selenite fertilization and water management.

Science.gov (United States)

Wan, Yanan; Camara, Aboubacar Younoussa; Huang, Qingqing; Yu, Yao; Wang, Qi; Li, Huafen

2018-07-30

The accumulation of arsenic (As) in rice grain is a potential threat to human health. Our study investigated the possible mediatory role of selenite fertilization on As uptake and accumulation by rice (Oryza sativa L.) under different water management regimes (aerobic or flooded) in a pot experiment. Soil solutions were also extracted during the growing season to monitor As dynamics. Results showed that As contents in the soil solutions, seedlings, and mature rice were higher under flooded than under aerobic water management. Under aerobic conditions, selenite additions slightly increased As concentrations in soil solutions (in the last two samplings), but decreased As levels in rice plants. Relative to the control, 0.5 mg kg -1 selenite decreased rice grain As by 27.5%. Under flooded conditions, however, selenite additions decreased As in soil solutions, while increased As in rice grain. Tendencies also showed that selenite additions decreased the proportion of As in rice shoots both at the seedling stage and maturity, and were more effective in aerobic soil. Our results demonstrate that the effect of selenite fertilizer on As accumulation by rice is related to water management. Copyright © 2018 Elsevier Inc. All rights reserved.

Log analysis in the shallow oil sands of the San Joaquin Valley, California

International Nuclear Information System (INIS)

Vohs, J.B.

1976-01-01

Many fields in the San Joaquin Valley of California produce oil from a depth of 2,500 ft or less. During the period of primary production in these fields, evaluation of potential pay intervals from logs was restricted to examination of ES logs and correlation. With the introduction of secondary and tertiary recovery techniques the need for more and better answers, more quickly available, became apparent. However, several log-analysis problems had to be resolved. Formation evaluation using well logs was complicated by the shaliness of the sand intervals, the low and variable salinity of the formation waters, and the presence of low-pressure-gas (depleted) zones in many of the shallow sands. Solutions to these problems have required more modern logging programs and interpretation techniques. Logs available for the evaluation of these sands are the dual induction-laterolog, the compensated formation density log, the compensated neutron log, and the microlaterolog or proximity log. With this suite of logs it is possible to determine the shale content, porosity, saturation in the flushed zone, and water saturation of the sand, and to locate the low-pressure-gas sands and depleted zones. In cases where freshwater and oil are interlayered, it is possible to tell which sands contain oil and which contain only water. Because a quick interpretation is required, wellsite techniques are called for. These will be described

The extraction of bitumen from western tar sands. Annual report, July 1990--July 1991

Energy Technology Data Exchange (ETDEWEB)

Oblad, A.G.; Bunger, J.W.; Deo, M.D.; Hanson, F.V.; Miller, J.D.; Seader, J.D.

1992-04-01

Contents of this report include the following: executive summary; characterization of the native bitumen from the Whiterocks oil sand deposit; influence of carboxylic acid content on bitumen viscosity; water based oil sand separation technology; extraction of bitumen from western oil sands by an energy-efficient thermal method; large- diameter fluidized bed reactor studies; rotary kiln pyrolysis of oil sand; catalytic upgrading of bitumen and bitumen derived liquids; ebullieted bed hydrotreating and hydrocracking; super critical fluid extraction; bitumen upgrading; 232 references; Appendix A--Whiterocks tar sand deposit bibliography; Appendix B--Asphalt Ridge tar sand deposit bibliography; and Appendix C--University of Utah tar sands bibliography.

Sandy soil plantation in semi-arid zones by polyacrylamide gel conditioner prepared by ionizing radiation. Part of a coordinated programme on radiation modified polymers for biomedical and biochemical applications

International Nuclear Information System (INIS)

Azzam, R.A.I.

1983-07-01

Polyacrylamide gel prepared by ionizing radiation was found to be capable of furnishing adequate conditions for sandy-soil plantation in semi-arid zones. The gel can be tailored for any soil texture under various climatic conditions. The sand-gel combination maintains three cycles of complete destruction and reformation without significant changes in erosion index. Water holding capacity and retention at different suctions in treated sand are increased. This increases water use efficiency. Fertilizers use efficiency is also increased to almost three times that of fertile clayey soil

Growth of Escherichia coli O157:H7, Non-O157 Shiga Toxin-Producing Escherichia coli , and Salmonella in Water and Hydroponic Fertilizer Solutions.

Science.gov (United States)

Shaw, Angela; Helterbran, Kara; Evans, Michael R; Currey, Christopher

2016-12-01

The desire for local, fresh produce year round is driving the growth of hydroponic growing systems in the United States. Many food crops, such as leafy greens and culinary herbs, grown within hydroponics systems have their root systems submerged in recirculating nutrient-dense fertilizer solutions from planting through harvest. If a foodborne pathogen were introduced into this water system, the risk of contamination to the entire crop would be high. Hence, this study was designed to determine whether Escherichia coli O157:H7, non-O157 Shiga toxin-producing E. coli , and Salmonella were able to survive and reproduce in two common hydroponic fertilizer solutions and in water or whether the bacteria would be killed or suppressed by the fertilizer solutions. All the pathogens grew by 1 to 6 log CFU/ml over a 24-h period, depending on the solution. E. coli O157:H7 reached higher levels in the fertilizer solution with plants (3.12 log CFU/ml), whereas non-O157 Shiga toxin-producing E. coli and Salmonella reached higher levels in the fertilizer solution without plants (1.36 to 3.77 log CFU/ml). The foodborne pathogens evaluated here survived for 24 h in the fertilizer solution, and populations grew more rapidly in these solutions than in plain water. Therefore, human pathogens entering the fertilizer solution tanks in hydroponic systems would be expected to rapidly propagate and spread throughout the system and potentially contaminate the entire crop.

Permeability Tests on Silkeborg Sand No. 0000

DEFF Research Database (Denmark)

Lund, Willy; Jakobsen, Kim Parsberg

on the characteristics of the soil matrix, the permeability is determined for different void ratios. All tests are performed on reconstituted specimens of Silkeborg Sand No. 0000. The permeability is determined by use of a falling head apparatus. The apparatus, test procedures and the analysis method are described......The flow through porous media plays an important role in various engineering disciplines, as for example in ground water hydrology and soil mechanics. In the present study the permeability is determined for a fine, saturated sand. As the flow through a porous media strongly depends...

Sugarcane bagasse derivative-based superabsorbent containing phosphate rock with water-fertilizer integration.

Science.gov (United States)

Zhong, Kang; Zheng, Xi-Liang; Mao, Xiao-Yun; Lin, Zuan-Tao; Jiang, Gang-Biao

2012-10-01

To improve the water-fertilizer utilization ratio and mitigate the environmental contamination, an eco-friendly superabsorbent polymer (SPA), modified sugarcane bagasse/poly (acrylic acid) embedding phosphate rock (MSB/PAA/PHR), was prepared. Ammonia, phosphate rock (PHR) and KOH were admixed in the presence of acrylic acid to provide nitrogen (N), phosphorus (P) and potassium (K) nutrients, respectively. Impacts on water absorption capacity of the superabsorbent polymer (SAP) were investigated. The maximum swelling capacity in distilled water and 0.9 wt.% (weight percent) NaCl solution reached 414 gg(-1) and 55 gg(-1) (water/prepared SAP), respectively. The available NPK contents of the combination system were 15.13 mgg(-1), 6.93 mgg(-1) and 52.05 mgg(-1), respectively. Moreover, the release behaviors of NPK in the MSB/PAA/PHR were also studied. The results showed that the MSB/PAA/PHR has outstanding sustained-release plant nutrients property. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of N-fertilizer rates on Dry Matter Yield (DMY) and quality of ...

African Journals Online (AJOL)

Effect of N-fertilizer rates on Dry Matter Yield (DMY) and quality of pinapple propagules (Ananas comosus) in the acid sands of cross river. W Ubi, M W Ubi, VE Osedeke. Abstract. No Abstract. Global Journal of Pure and Applied Physics Vol. 14 (1) 2008 pp. 1-4. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD ...

Arsenic Removal from Drinking Water by Absorptive Media-U.S. EPA Demonstration Project at Desert Sands MDWCA, NM Final Performance Evaluation Report

Science.gov (United States)

This report documents the activities performed and the results obtained for the arsenic removal treatment technology demonstration project at the Desert Sands Mutual Domestic Water Consumers Association (MDWCA) facility in Anthony, NM. The objectives of the project were to evalu...

Reclaimability of the spent sand mixture – sand with bentonite – sand with furfuryl resin

Directory of Open Access Journals (Sweden)

J. Dańko

2011-04-01

Full Text Available Introduction of new binding materials and new technologies of their hardening in casting moulds and cores production requires theapplication of reclamation methods adequate to their properties as well as special devices realizing tasks. The spent sands circulationsystem containing the same kind of moulding and core sands is optimal from the point of view of the expected reclamation results.However, in the face of a significant variability of applied technologies and related to them various reclamation methods, the need - of theobtained reclamation products assessment on the grounds of systematic criteria and uniform bases – arises, with a tendency of indicatingwhich criteria are the most important for the given sand system. The reclaimability results of the mixture of the spent moulding sand withGeko S bentonite and the spent core sand with the Kaltharz 404U resin hardened by acidic hardener 100 T3, are presented in the paper.Investigations were performed with regard to the estimation of an influence of core sands additions (10 –25% on the reclaimed materialquality. Dusts and clay content in the reclaim, its chemical reaction (pH and ignition loss were estimated. The verification of the reclaiminstrumental assessment was performed on the basis of the technological properties estimation of moulding sand with bentonite, where the reclaimed material was used as a matrix.

Effects of pre-incubation of eggs in fresh water and varying sperm concentration on fertilization rate in sterlet sturgeon, Acipenser ruthenus

DEFF Research Database (Denmark)

Siddique, Mohammad Abdul Momin; Butts, Ian; Psěnička, Martin

2015-01-01

, while it was significant at the 4300:1 and 430:1 ratios. The use of adequate experimental suboptimal sperm to egg ratio revealed a positive effect of pre-incubation time, such that at the 430:1 ratio, 0.5. min pre-incubation increased the fertilization rate than 10. min. At 0. min pre......-incubation the proportion of fertilized eggs increased at the 430,000:1 ratio, while at 1. min fertilization increased at the 4300:1 ratio. At the 10. min pre-incubation time, fertilization increased at the 43,000:1 ratio. Moreover, at the 0.5. min pre-incubation time, the 43,000:1 ratio increased the fertilization rate...... than the 430:1 ratio. Generally, for 430:1 ratio, the fertilization rate is lower than in control. Transmission electron microscopy showed that pre-incubation of eggs in water for

Effect of probiotic and sand filtration treatments on water quality and growth of tilapia (Oreochromis niloticus) and pangas (Pangasianodon hypophthalmus) in earthen ponds of southern Bangladesh

DEFF Research Database (Denmark)

Mahmud, Sultan; Ali, Mohammad Lokman; Alam, Md Ariful

2016-01-01

Effects of water treatment by two probiotic products (PondPlus® and AquaPhoto®) and sand filtration were studied on growth performance of tilapia (Oreochromis niloticus) and pangas (Pangasianodon hypophthalmus) stocked at tilapia:pangas ratio of 5:3 in traditional earthen ponds in Bangladesh....... The fish were stocked at a density of 20,000 fish ha−1 and reared for 7 months. Compared to untreated ponds, treatments of probiotic products or sand filtration in earthen ponds resulted in a higher O2 content, higher water transparency, less ammonium, and fewer cyanobacteria. Weight gain for individual...... tilapia was lowest in the AquaPhoto-treated ponds (177 g), while similar gains (188–194 g) occurred in the other ponds. For pangas, the lowest weight gain (627 g) was obtained in the sand filter-treated ponds, as compared to 690–797 g in the other ponds. Thus, a general positive effect from the treatments...

Does fertilizer (N15P15K15) amendment enhance phytoremediation of petroleum-polluted aquatic ecosystem in the presence of water hyacinth (Eichhornia crassipes [Mart.] Solms)?

Science.gov (United States)

Ndimele, Prince Emeka; Jenyo-Oni, Adetola; Chukwuka, Kanayo S; Ndimele, Chinatu Charity; Ayodele, Ibukunoluwa Augustine

2015-01-01

This study investigated the effects of inorganic fertilizer (N15P15K15) amendments on crude oil uptake by water hyacinth. Experimental units (water hyacinth grown in fresh water) were spiked with 0, 20, 40 and 60 mg/L crude oil. After 24 h, they were randomly assigned fertilizer (N15P15K15) at three different concentrations; 0, 6 and 10 mg/L. Crude oil degradation and absorption were determined by measuring total petroleum hydrocarbon (TPH) in the water column and water hyacinth, respectively. The measurements were taken monthly for six months (February-August 2010). The results showed that TPH concentration in the water column in the treatment amended at 6 mg/L (0.30 ± 0.01 mg/L) was significantly lower (p phytoremediation) absorbed significantly higher (p phytoremediation of crude oil by water hyacinth and biostimulation with fertilizer (N15P15K15) is possible.

Use of post-thaw semen quality parameters to predict fertility of water buffalo (Bubalus bubalis) bull during peak breeding season.

Science.gov (United States)

Ahmed, H; Andrabi, S M H; Anwar, M; Jahan, S

2017-05-01

This study was designed to predict the fertility of water buffalo bull using post-thaw semen quality parameters during peak breeding season. Thirty ejaculates were collected from five bulls with artificial vagina and cryopreserved. At post-thaw, semen was analysed for motility parameters, velocity distribution, kinematics, DNA integrity/fragmentation, viability, mitochondrial transmembrane potential, morphology, plasma membrane and acrosome integrity. Data of 514 inseminations were collected for estimation of in vivo fertility. Pearson's correlation coefficients showed that progressive motility (PM), rapid velocity, average path velocity, straight line velocity, straightness, supravital plasma membrane integrity, viable spermatozoon with intact acrosome or with high mitochondrial activity were correlated with in vivo fertility (r = .81, p fertility was PM. However, combinations of semen quality parameters to predict fertility were better as compared to single parameter. In conclusion, fertility of buffalo bull can be predicted through some of the post-thaw in vitro semen quality tests during peak breeding season. © 2016 Blackwell Verlag GmbH.

Biochar-organic amendment mixtures added to simulated golf greens under reduced chemical fertilization increase creeping bentgrass growth

Science.gov (United States)

Simulated golf greens were used to test the growth of creeping bentgrass (Agrostis stolonifera L. "007") receiving suboptimal chemical fertilization in sand based substrates amended with 15% peat (control), a commercial biochar, a commercial biochar-compost (CarbonizPN), or seven formulated biochar...

Water/sand flooded and immersed critical experiment and analysis performed in support of the TOPAZ-II Safety Program

International Nuclear Information System (INIS)

Glushkov, E.S.; Ponomarev-Stepnoi, N.N.; Bubelev, V.G.; Garin, V.P.; Gomin, E.A.; Kompanietz, G.V.; Krutoy, A.M.; Lobynstev, V.A.; Maiorov, L.V.; Polyakov, D.N.

1994-01-01

Presented is a brief description of the Narciss-M2 critical assemblies, which simulate accidental water/wet-sand immersion of the TOPAZ-II reactor as well as water-flooding of core cavities. Experimental results obtained from these critical assemblies, including experiments with several fuel elements removed from the core, are shown. These configurations with several extracted fuel elements simulate a proposed fuel-out anticriticality-device modification to the TOPAZ-II reactor. Preliminary computational analysis of these experiments using the Monte Carlo neutron-transport method is outlined. Nuclear criticality safety of the TOPAZ-II reactor with an incorporated anticriticality unit is demonstrated

Water regime-nitrogen fertilizer incorporation interaction: Field study on methane and nitrous oxide emissions from a rice agroecosystem in Harbin, China.

Science.gov (United States)

Dong, Wenjun; Guo, Jia; Xu, Lijun; Song, Zhifeng; Zhang, Jun; Tang, Ao; Zhang, Xijuan; Leng, Chunxu; Liu, Youhong; Wang, Lianmin; Wang, Lizhi; Yu, Yang; Yang, Zhongliang; Yu, Yilei; Meng, Ying; Lai, Yongcai

2018-02-01

Water regime and nitrogen (N) fertilizer are two important factors impacting greenhouse gases (GHG) emission from paddy field, whereas their effects have not been well studied in cold region. In this study, we conducted a two-year field experiment to study the impacts of water regime and N fertilizer on rice yields and GHG emissions in Harbin, China, a cold region located in high latitudes. Our results showed that intermittent irrigation significantly decreased methane (CH 4 ) emission compared with continuous flooding, however, the decrement was far lower than the global average level. The N 2 O emissions were very small when flooded but peaked at the beginning of the disappearance of floodwater. The N fertilizer treatments increased CH 4 emissions at low level (75kgN/ha). But both CH 4 and N 2 O emissions were uninfluenced at the levels of 150kgN/ha and 225kgN/ha. Rice yields increased under intermittent irrigation and were highest at the level of 150kgN/ha. From our results, we recommended that the intermittent irrigation and 150kgN/ha as the ideal water regime-nitrogen fertilizer incorporation for this area to achieve low GHG emissions without impacting rice yields. Copyright © 2017. Published by Elsevier B.V.

A study of global sand seas

Science.gov (United States)

McKee, Edwin D.

1979-01-01

associated with eolian hydrocarbon reservoirs. The final chapters present a discussion of the morphology and distribution of dunes as determined largely from Landsat images.Chapter K of the publication is devoted to descriptions of major sand seas based largely on thematic maps derived from Landsat (ERTS) mosaics. Although inclusion herein of the actual mosaics proved to be impractical, the maps derived from them do show the distribution and abundance of various dune types and the relations of these types to certain associated features, such as bedrock, water bodies, and juxtaposed dunes. Furthermore, sand roses included with each of these maps enable the user to draw conclusions on the probable relations of wind strength and direction to dune type in a particular area.Regional studies (chapter K) were a team effort. Analysis of the Landsat (ERTS) mosaics and mapping boundaries of individual dune types were by Carol Breed. Synthesis of the rather voluminous literature and preparation of abstracts covering it was by Camilla MacCauley. Actual preparation of maps was by Franci Lennartz and later by Sarah Andrews. The gathering of data on wind, the calculation of wind roses, and the interpretation of their relations to sand bodies were by Steven Fryberger, assisted by Gary Dean.

An Investigation into the Use of Manufactured Sand as a 100% Replacement for Fine Aggregate in Concrete

Directory of Open Access Journals (Sweden)

Martins Pilegis

2016-06-01

Full Text Available Manufactured sand differs from natural sea and river dredged sand in its physical and mineralogical properties. These can be both beneficial and detrimental to the fresh and hardened properties of concrete. This paper presents the results of a laboratory study in which manufactured sand produced in an industry sized crushing plant was characterised with respect to its physical and mineralogical properties. The influence of these characteristics on concrete workability and strength, when manufactured sand completely replaced natural sand in concrete, was investigated and modelled using artificial neural networks (ANN. The results show that the manufactured sand concrete made in this study generally requires a higher water/cement (w/c ratio for workability equal to that of natural sand concrete due to the higher angularity of the manufactured sand particles. Water reducing admixtures can be used to compensate for this if the manufactured sand does not contain clay particles. At the same w/c ratio, the compressive and flexural strength of manufactured sand concrete exceeds that of natural sand concrete. ANN proved a valuable and reliable method of predicting concrete strength and workability based on the properties of the fine aggregate (FA and the concrete mix composition.

An Investigation into the Use of Manufactured Sand as a 100% Replacement for Fine Aggregate in Concrete.

Science.gov (United States)

Pilegis, Martins; Gardner, Diane; Lark, Robert