Series Of Ponds Research Articles

Spatio‐temporal sedimentation patterns in beaver ponds along the Chevral river, Ardennes, Belgium

AbstractWith the recovery of the European beaver (Castor fiber) and their capacity to engineer fluvial landscapes, questions arise as to how they influence sediment transport, including the spatio‐temporal trends and patterns of sedimentation in beaver ponds. The Chevral river (Ardennes, Belgium) contains two beaver dam sequences, which appeared in 2004. Volumes of sediment deposited behind the dams were measured, and grain‐size distribution patterns were determined. Flow discharges and sediment fluxes were measured at the inflow and outflow of each dam sequence. Between 2004 and 2011, 1710.1 m3 of sediment was deposited behind the beaver dams, with an average sediment thickness of 25.1 cm. The thickness of the sediment layer was significantly (p < 0.001) related to the area of the beaver ponds. Along the stream, beaver pond sediment thickness displayed a sinusoidal deposition pattern, in which ponds with thick sediment layers were preceded by a series of ponds with thinner sediment layers. A downstream textural coarsening in the dam sequences was also observed, probably because of dam failures subsequent to surges. Differences in sediment flux between the inflow and outflow at the beaver pond sequence were related to the river hydrograph, with deposition taking place during the rising limbs and slight erosion during the falling limbs. The 7‐year‐old sequences have filtered 190.19 ton of sediment out of the Chevral river, which is of the same order of magnitude as the 374.4 ton measured in pond deposits, with the difference between the values corresponding to beaver excavations (60.24 ton), inflow from small tributaries, and runoff from the valley flanks. Hydrogeomorphic effects of C. fiber and Castor canadensis activity are similar in magnitude. The detailed analysis of sedimentation in beaver pond sequences confirms the potential of beavers to contribute to river and wetland restoration, and catchment management. Copyright © 2013 John Wiley & Sons, Ltd.

Effect of Hydraulic Retention Time (HRT) on Surveillance of Coliforms in Waste Stabilization Pond (WSP) System in Central India

The content of total coliforms and fecal coliforms were measured for the different ponds (anaerobic, facultative and maturation) in the year 2008-09 for waste stabilization pond (WSP) system in terms of Log 10 reduction value and decay rate (k d -1 ) in order to determine the efficacy of waste stabilization ponds with respect to their hydraulic retention time (HRT). Physical and chemical parameters (temperature, hydrogen ion concentration, total suspended solids and total dissolved solids) were also determined with aim of finding the factors which influence the rate of coliforms removal. The results indicate the surveillance of coliforms were most favored in anaerobic cell and lest favored in maturation cell with decay rate to an average of (k d-1 =2.92); (k d-1=4.88); (k d-1 = 5.83) and (k d-1=2.80) and (k d -1 =4.30); (k d -1 =5.89) for total coliforms and fecal coliforms observed for anaerobic, facultative and maturation cells respectively. The highest removal of coliforms (total and fecal coliforms) between 3.37 log10 to 4.0 log10 was observed for maturation cells with hydraulic retention time (HRT) of 5 days each and two maturation ponds in series.

Importance of the ammonia volatilization rates in shallow maturation ponds treating UASB reactor effluent

This study aimed at determining the influence of ammonia volatilization on nitrogen removal in polishing (maturation) ponds treating sanitary effluent from upflow anaerobic sludge blanket (UASB) reactors in the city of Belo Horizonte, Brazil. An apparatus for the capture and absorption of volatilized ammonia in three polishing ponds in series was installed. Volatilized ammonia was captured by a chamber on the surface of the ponds and dissolved in boric acid solution, in order to estimate the amount of ammonia per unit surface area of each pond. Low rates of volatilization, below 0.2 kg/ha.d, in about 75% of samples from all the ponds, were observed. The mass balance of ammonia nitrogen of the ponds showed that the volatilization represented only about 2% of the total removal of nitrogen from the polishing ponds. The results obtained suggest that ammonia volatilization was a mechanism of little importance in nitrogen removal in the investigated polishing ponds.

Study of a Constructed Wetland-Pond System for Treatment from Campus Buildings

A constructed wetland-pond system consisting of a subsurface-flow (SSF) wetland, and a scenic pond in series was used for reclamation of septic tank effluent from a campus building. The results show that SSF wetlands effectively removed major pollutants under a hydraulic loading rate between 3.6 and 7.1 cm/d, with average efficiencies ranging from 85% to 86% for TSS, and 71% to 84% for BOD5. There were a variety of ornamental plants and aquatic animals established in the scenic pond with good water quality, thus enhancing landscape and ecology amenity in campuses.

Nutrient recovery from swine waste and protein biomass production using duckweed ponds (Landoltia punctata): Southern Brazil

Brazil is one of the most important countries in pork production worldwide, ranking third. This activity has an important role in the national economic scenario. However, the fast growth of this activity has caused major environmental impacts, especially in developing countries. The large amount of nitrogen and phosphorus compounds found in pig manure has caused ecological imbalances, with eutrophication of major river basins in the producing regions. Moreover, much of the pig production in developing countries occurs on small farms, and therefore causes diffuse pollution. Therefore, duckweed pond have been successfully used in the swine waste polishing, generating further a biomass with high protein content. The present study evaluated the efficiency of two full scale duckweed ponds for the polishing of a small pig farm effluent, biomass yield and crude protein (CP) content. Duckweed pond series received the effluent from a biodigester-storage pond, with a flow rate of 1 m(3)/day (chemical oxygen demand rate = 186 kg/ha day) produced by 300 animals. After 1 year a great improvement of effluent quality was observed, with removal of 96% of total Kjeldahl nitrogen (TKN) and 89% of total phosphorus (TP), on average. Nitrogen removal rate is one of the highest ever found (4.4 g TKN/m(2) day). Also, the dissolved oxygen rose from 0.0 to 3.0 mg/L. The two ponds produced together over 13 tons of fresh biomass (90.5% moisture), with 35% of CP content, which represents a productivity of 24 tonsCP/ha year. Due to the high rate of nutrient removal, and also the high protein biomass production, duckweed ponds revealed, under the presented conditions, a great potential for the polishing and valorization of swine waste. Nevertheless, this technology should be better exploited to improve the sustainability of small pig farms in order to minimize the impacts of this activity on the environment.

Heavy metal removal in duckweed and algae ponds as a polishing step for textile wastewater treatment

Untreated textile wastewater is a typical source of heavy metal pollution in aquatic ecosystems. In this study, the use of algae and duckweed ponds as post-treatment for textile wastewater has been evaluated under the hypothesis that differing conditions such as pH, redox potential and dissolved oxygen in these ponds would lead to different heavy metal removal efficiencies. Two lab-scale systems each consisting of three ponds in series and seeded with algae (natural colonisation) and duckweed (Lemna minor), respectively, have been operated at a hydraulic retention time of 7 days and under two different metal loading rates and light regimes (16/8h light/darkness and 24h light). Cr removal rates were 94% for the duckweed ponds and 98% for the algal ponds, indifferently of the metal loading rate and light regime. No effect of pond type could be demonstrated for Zn removal. Under the 16/8 light regime, Zn removal proceeded well (∼70%) at a low metal loading rate, but dropped to below 40% at the higher metal loading rate. The removal efficiency raised back to 80% at the higher metal loading rate but under 24h light regime. Pb, Cd and Cu all showed relatively similar patterns with removal efficiencies of 36% and 33% for Pb, 33% and 21% for Cd and 27% and 29% for Cu in the duckweed and the algal ponds, respectively. This indicates that both treatment systems are not very suitable as a polishing step for removing these heavy metals. Despite the significant differences in terms of physico-chemical conditions, differences in metal removal efficiency between algal and duckweed ponds were rather small.

Assessment of pollutant loads discharged from aquaculture ponds around Taihu Lake, China

China is the world's largest producer of aquatic animals, and the Taihu Lake area is one of the most important contributors within China. To obtain the basic information needed to minimize environmental impacts of aquaculture, the water quality and volume of effluents from 48 ponds used for raising crab, shrimp, river prawn, black carp, grass carp and turtles near Taihu Lake were monitored, and their pollutant loads were estimated. Effluent volumes ranged from 12.7 ± 1.7 (crab) to 50.9 ± 15.8 (turtle) thousand tons ha−1 year−1. The concentration of pollutants in the effluents often exceeded acceptable limits for Taihu Lake. Crab ponds produced the lowest gross loads of total nitrogen, total phosphorus, chemical oxygen demand and total suspended solids, whereas turtle ponds produced the highest. The net loads of monitored pollutants comprised only 4–53% of the gross loads in crab ponds, but > 50% in other species ponds. Results indicate that the pollutant loads discharged from aquaculture ponds around Taihu Lake are mild, but precautions are still needed to treat the wastewater. Connecting the ponds in series with crab ponds downstream is a feasible way to decrease pollutant loads.

Removal of faecal bacteria from septage by treating it in a full-scale duckweed-covered pond system

Performance of a full-scale duckweed-covered treatment system in removing faecal bacteria is presented. The system consisted of three ponds in series and received septage from holding tanks. Inflow averaged between 36m(3)d(-1) in the cold season and 60m(3)d(-1) in the warm season, resulting in a total hydraulic retention time of 88 and 58 days, respectively. Duckweed (Lemna minor) colonized the ponds in the summer and continued to grow in the cold season. Due to the difficult harvesting process of the duckweed biomass, the investigation of the treatment efficiency was carried out without plant harvesting. The system was monitored for temperature, pH, oxygen, chlorophyll-a, Escherichia coli and Enterococci. Duckweed growth resulted in chlorophyll-a concentration reduction from 924 to 13μgL(-1), causing neutral and anoxic conditions in the pond water. A temperature effect was noticed on the E.coli decay coefficient with a decreasing trend along the treatment system. Enterococci always decayed less than E.coli. Differences on decay coefficients and removal efficiencies were not observed between the three ponds for both bacterial types. Effluent quality in terms of E.coli was 489 and 1377cfu/100mL, in the warm and the cold seasons, respectively, with average removals of 99.65±1.46% and 99.33±3.03%. Total Enterococci removal was 88.91±23.1% in the warm season and 94.43±24.45% in the cold season, resulting in mean effluent values of 1058 and 1404cfu/100mL, respectively. The seasonal differences in total removal efficiencies were insignificant for both bacterial types.

Performance of a constructed wetland for treating farm-yard dirty water

Constructed wetlands (CWs) have been used to treat agricultural effluents with varying success especially with respect to their operational efficiency in winter and ability to retain phosphorus. Dirty water (DW) from dairy farms is a mixture of manure contaminated runoff and milk parlour washings with a highly polluting biochemical oxygen demand (BOD) < or =3000 mg/L. The initial performance a CW of a 1.2 ha horizontal flow CW consisting of five ponds in series designed to treat DW from a dairy unit was assessed over four years. Ponds were earth-lined and shallow (0.3 m) with a water residence time of 100 days and planted with five species of emergent macrophytes. In comparison to CW inflow, annual reductions were as follows: BOD 99%, P 95% and N 92.8%. Coliforms were reduced by a 10(-5) factor to natural levels. From May to October there was little CW discharge due to evaporative losses. Final effluent quality was poorest in February but remained within a regulatory effluent standard for BOD of 40 mg/L. If the CW had only four ponds (25% less surface area) effluent would have failed the BOD standard in three years.

Rootless shield and perched lava pond collapses at Kīlauea Volcano, Hawai'i

Effusion rate is a primary measurement used to judge the expected advance rate, length, and hazard potential of lava flows. At basaltic volcanoes, the rapid draining of lava stored in rootless shields and perched ponds can produce lava flows with much higher local effusion rates and advance velocities than would be expected based on the effusion rate at the vent. For several months in 2007–2008, lava stored in a series of perched ponds and rootless shields on Kīlauea Volcano, Hawai'i, was released episodically to produce fast-moving 'a'ā lava flows. Several of these lava flows approached Royal Gardens subdivision and threatened the safety of remaining residents. Using time-lapse image measurements, we show that the initial time-averaged discharge rate for one collapse-triggered lava flow was approximately eight times greater than the effusion rate at the vent. Though short-lived, the collapse-triggered 'a'ā lava flows had average advance rates approximately 45 times greater than that of the pāhoehoe flow field from which they were sourced. The high advance rates of the collapse-triggered lava flows demonstrates that recognition of lava accumulating in ponds and shields, which may be stored in a cryptic manner, is vital for accurately assessing short-term hazards at basaltic volcanoes.

Assessment of a full‐scale duckweed pond system for septage treatment

Environmental conditions and wastewater treatment performance in a full‐scale duckweed pond system are presented. The treatment system consisted of three stabilization ponds in series and was fed with septage. Vacuum trucks pumped the septage from residential holding tanks and discharged it to the system daily. The inflow rates averaged 36 m3 d−1 in the cold season and 60 m3 d−1 in the warm season. Duckweed (Lemna minor) colonized the ponds in the warm months and survived during the cold season. Because of the difficult process for harvesting the duckweed biomass, the investigation of the treatment efficiency was carried out without plant harvesting. Samples were collected from the vacuum trucks and from the exit of each pond and were analysed for physicochemical and microbiological parameters over a period of 12 months. The results showed that the duckweed mat suppressed algal biomass, which in turn led to anoxic and neutral pond conditions. On an annual basis, the duckweed system sufficiently removed BOD5 (94%), NH4 + (72%) and E. coli (99.65%), with lower removal of TSS (63%) and Enterococci (91.76%). A slight increase (1.1%) was recorded for o‐PO4 3−. Between the two sampling seasons, BOD5 and TSS removal efficiencies were higher in the cold season with the longer retention time. Similar removal values in the warm and the cold season were found for nutrients and bacteria. These findings indicate that BOD5 and TSS removals are less temperature‐dependent at higher retention times, while ammonia nitrogen and bacterial removals are substantially influenced by temperature as well as retention time.

Ponds, Paddies and Frontier Defence

At the end of the 10th century, the Northern Song government constructed a series of ponds in northern Hebei in order to thwart its nomadic rival, the Khitan Liao. Throughout the following one and a quarter centuries of the dynasty, this strategic set of water features was enlarged, despite the environmental and human costs. This article looks at the history of these ponds, and paddy rice planting in this area, and explores their interaction with Hebei’s economy and environment during the period. It argues that the presence of these ponds dramatically changed the ecology of northern Hebei and brought about a series of political and economic problems: not only were local residents driven to find alternative means of livelihood or to emigrate out, but the government also came under significant economic pressure and committed itself to an unsuccessful policy of paddy rice production. The problems caused by this strategic military scheme played a significant role in the economic decline, especially of agriculture, of northeast China during the middle period of Chinese history.

UASB-polishing ponds design parameters: contributions from a pilot scale study in southeast Brazil

This paper presents the results of five years monitoring of an experimental wastewater treatment plant in southeast Brazil, comprised of a UASB reactor followed by a submerged aerated biofilter (BF) (field scale) and shallow polishing ponds (pilot scale). Three ponds in series achieved high quality effluent standards in terms of ammonia and E.coli, but a fourth pond did not result in further efficiency. Well established models to predict ammonia and E.coli removal in facultative and/or maturation ponds were, in a way, validated for polishing ponds too. The paper also includes results of input design parameters, such as pH and E.coli die-off rate constants, and their variation along the pond series.

Prospectus of waste stabilization ponds in Ceará, Northeast Brazil

WSP technology has been used in Ceará, Northeast Brazil, since middle 1970s. There are presently 96 ponds plants and most of them are comprised by single cells (40%) and series of 3 ponds (35%). They were under loaded due to incomplete house connections to the sewerage network and low per capita wastewater contributions. Highest removal rates of organic material, ammonia and faecal coliform were found in 3 pond series. Faecal coliform removal was in accordance with the literature and series of ponds reached numbers ≤10(5) cells/100 ml. In series with 4 and 5 ponds FC was below 10(3) cells/100 ml. Ammonia removal varied from 30 to 80% and total phosphorus the removal was not significant. An increase in the number of maturation ponds enhances nutrient and coliform removal. Up-grading schemes should be investigated as well as effluent reuse potential.

The removal of ammonia from sanitary landfill leachate using a series of shallow waste stabilization ponds

This study evaluated the efficiency of a shallow (0.5 m deep) waste stabilization pond series to remove high concentrations of ammonia from sanitary landfill leachate. The pond system was located at EXTRABES, Campina Grande, Paraiba, Northeast Brazil. The pond series was fed with sanitary landfill leachate transported by road tanker to the experimental site from the sanitary landfill of the City of Joao Pessoa, Paraiba. The ammoniacal-N surface loading on the first pond of the series was equivalent to 364 kg ha(-1) d(-1) and the COD surface loading equivalent to 3,690 kg ha(-1) d(-1). The maximum mean ammonia removal efficiency was 99.5% achieved by the third pond in the series which had an effluent concentration of 5.3 mg L(-1) ammoniacal-N for an accumulative HRT of 39.5 days. The removal process was mainly attributed to ammonia volatilization (stripping) from the pond surfaces as a result of high surface pH values and water temperatures of 22-26°C. Shallow pond systems would appear to be a promising technology for stripping ammonia from landfill leachate under tropical conditions.

Handling and Treatment of Poultry Hatchery Waste: A Review

A literature review was undertaken to identify methods being used to handle and treat hatchery waste. Hatchery waste can be separated into solid waste and liquid waste by centrifuging or by using screens. Potential methods for treating hatchery waste on site include use of a furnace to heat the waste to produce steam to run a turbine generator or to use an in line composter to stabilise the waste. There is also potential to use anaerobic digestion at hatcheries to produce methane and fertilisers. Hatcheries disposing wastewater into lagoons could establish a series of ponds where algae, zooplankton and fish utilise the nutrients using integrated aquaculture which cleans the water making it more suitable for irrigation. The ideal system to establish in a hatchery would be to incorporate separation and handling equipment to separate waste into its various components for further treatment. This would save disposal costs, produce biogas to reduce power costs at plants and produce a range of value added products. However the scale of operations at many hatcheries is too small and development of treatment systems may not be viable.

Nutrients and water level fluctuations: A study of three aquatic plants

ABSTRACTWater holes characteristic of the middle sections of fragmented, lowland, semi‐arid rivers act as refuge areas for biota during low flow and drought. However, river regulation and catchment development has altered the hydrological and nutrient status of these refuges. A series of artificial ponds were used to imitate these habitats and experiments were designed to determine whether stochastically fluctuating water levels with maximum amplitude of 65 cm would counteract the influence of nutrient enrichment on the growth of three key aquatic plant species. The species (Cyperus gymnocaulos, Triglochin procerum and Typha domingensis) represented different functional groups that inhabit contrasting zones across the elevation gradient. Each species was grown at a different elevation within the experiment reflecting each species' elevation preference and supplied with the equivalent to 0, 10 or 30 g N m−2 year−1. Under a static water regime nutrient enrichment doubled the total biomass of all three species. In contrast under a fluctuating water regime, nutrient addition did not influence total biomass of either T. domingensis or T. procerum and the performance of C. gymnocaulos was reduced by ca. 30%. These data suggest that if environmental flows were managed to provide a natural stochastically fluctuating water regime, this would nullify the influence of nutrient enrichment and limit the distribution and spread of invasive species such as Typha, that exists under the current altered conditions. Copyright © 2010 John Wiley &amp; Sons, Ltd.

Optimal Allocation of Rainfall in the Sichuan Basin, Southwest China

Traditional water allocation at a regional or basin scale can be too coarse to be used in a local area such as a village. For example, in the hilly area of Sichuan Basin the landform is fragmented and land use pattern consists of small farms. Furthermore, seasonal drought occurs frequently due to spatially and temporally variability in rainfall patterns. These droughts often lead to a reduction in crop yield or no yield at all. Due to the remoteness and scale of the farms, the farm populations are dependent on the annual crop yield. A poor harvest can mean serious hardships to the farmers. In order to mitigate the seasonal drought we first analyzed the drought characteristics from both meteorological and soil aspects. The results showed that both the spring droughts and canicular days (dog-day) droughts had in excess of a 60% chance of occurring. Using a water balance approach, we found that a series of storage ponds and bunds could greatly reduce the impact of these droughts.

Comparison between polishing (maturation) ponds and subsurface flow constructed wetlands (planted and unplanted) for the post-treatment of the effluent from UASB reactors

This paper presents the results of a comparison of the performance of two treatment systems operating in parallel, with the same influent wastewater. The investigated systems are (i) UASB + three polishing ponds in series + coarse filter (200 population equivalents) and (ii) UASB + subsurface flow constructed wetlands (50 population equivalents). Two wetland units, operating in parallel, were analysed, being one planted (Typha latifolia) and the other unplanted. The systems were located in Belo Horizonte, Brazil. The wetland systems showed to be more efficient in the removal of organic matter and suspended solids, leading to good effluent BOD and COD concentrations and excellent SS concentrations. The planted wetland performed better than the unplanted unit, but the latter was also able to provide a good effluent quality. The polishing pond system was more efficient in the removal of nitrogen (ammonia) and coliforms (E. coli). Land requirements and cost considerations are presented.

Investigation of aerobic and anaerobic ammonium-oxidising bacteria presence in a small full-scale wastewater treatment system comprised by UASB reactor and three polishing ponds

This work applied PCR amplification method and Fluorescence in situ hybridisation (FISH) with primers and probes specific for the anammox organisms and aerobic ammonia-oxidising beta-Proteobacteria in order to detect these groups in different samples from a wastewater treatment system comprised by UASB reactor and three polishing (maturation) ponds in series. Seven primer pairs were used in order to detect Anammox bacteria. Positive results were obtained with three of them, suggesting that Anammox could be present in polishing pond sediments. However, Anammox bacteria were not detected by FISH, indicating that they were not present in sediment samples, or they could be present but below FISH detection limit. Aerobic ammonia- and nitrite-oxidising bacteria were verified in water column samples through Most Probable Number (MPN) analysis, but they were not detected in sediment samples by FISH. Ammonia removal efficiencies occurred systematically along the ponds (24, 32, and 34% for polishing pond 1, 2, and 3, respectively) but the major reaction responsible for this removal is still unclear. Some nitrification might have occurred in water samples because some nitrifying bacteria were present. Also Anammox reaction might have occurred because Anammox genes were detected in the sediments, but probably this reaction was too low to be noticed. It is important also to consider that some of the ammonia removal observed might be related to NH(3) stripping, associated with the pH increase resulting from the intensive photosynthetic activity in the ponds (mechanism under investigation). Therefore, it can be concluded that more than one mechanism (or reaction) might be involved in the ammonia removal in the polishing ponds investigated in this study.