Studies on Stabilization Ponds for Domestic Sewage in India

For one year a single cell stabilization pond, T. T. Nagar, Bhopal (August, 1968 to July, 1969) and series stabilization ponds, Shahpur, Bhopal (January, 1969 to December, 1969) were studied. Climatological conditions in Bhopal were favourable for the treatment of sewage in stabilization ponds. There was a considerable reduction in BOD, total nitrogen, phosphate, coliforms and enterococci during the process of treatment. The reductions were highest in series ponds. Studies on diurnal variations showed that highest pH, dissolved oxygen, algal cell number and lowest alkalinity values occurred around 4.00 p.m. Algal flora present in the single cell pond consisted of 31 species representing 27 genera. In the series ponds 33 species belonging to 30 genera and 37 species belonging to 33 genera were recorded for the primary and secondary ponds, respectively.     

Signal Analysis of Irradiation,Temperature and Primary Production in a Small Artificial Pond. II. The Residual Spectra

Irradiation, water temperature and dissolved oxygen of a small artificial pond were continuously recorded over a two year period. Following the elimination of previously estimated mean trends and forced annual patterns (LINGEMAN 1980) a spectral analysis procedure is proposed and executed for the residual signals of total diurnal irradiation, diel mean temperature and diurnal gross primary production. The residual power spectrum of diurnal irradiation was shown to be essentially the one of a white noise. Several higher frequencies were significantly present in both the signals of temperature and production. Some consideration is given to the cross correlation between the latter two parameters.     

Diurnal Cycles of Sulfate Reduction under Oxic Conditions in Cyanobacterial Mats

Diurnal cycles of sulfate reduction were examined in a well-developed cyanobacterial mat which grew in an outdoor experimental hypersaline pond system at a constant salinity of 75 ± 5% for 3 years. Vertical profiles of sulfate reduction were determined for the upper 12 mm of the microbial mat. Sulfate reduction activities were compared with diurnal variations of oxygen and sulfide concentrations measured by microelectrodes. Significant activity of sulfate-reducing bacteria was detected under aerobic conditions during the daytime, with maximal activity at 2 p.m. When comparing sulfate reduction activities in sediment cores taken at 6 a.m. and 12 a.m. and incubated at a constant temperature in the light and in the dark, a distinct stimulation of the activity in the vertical profile of sulfate reduction by light was evident. It is therefore concluded that the maximal in situ activities, measured at 2 p.m. in the chemocline of the cyanobacterial mat, cannot be attributed to diurnal changes of temperature alone. The response of sulfate-reducing bacteria to the addition of specific carbon sources was significantly different in the cyanobacterial layer, the anoxygenic phototrophic bacterial layer, and the permanently reduced layer of the microbial mat. Sulfate reduction in the mat layer exposed to high oxygen concentrations as a result of cyanobacterial oxygenic photosynthesis was enhanced only by glycolate; in the microzone where the chemocline is found during the daytime, ethanol was the only carbon source to enhance sulfate reduction, while both ethanol and lactate enhanced this activity in the permanently reduced zone.     

Diurnal variations in a shallow tropical freshwater fish pond in Shahjahanpur,U.P. (India)

Summary Diurnal variations in water chemistry and plankton in this eutrophic tropical freshwater ponds were quite apparent. Large fluctuations were noted in dissolved oxygen, pH, carbonate and bicarbonate concentrations. The pond water gets oversaturated with oxygen during day (24.2 p.p.m.) and depleted in the night (1.2 p.p.m.). Diurnal migrations of plankton were not in conformity with temperate waters.     

轮虫培育池生态系统各有机碳库储量及其日变化

2001年5～6月对辽宁省盘锦光合水产有限公司的两种模式轮虫培育池有机碳库储量及动态进行了研究.结果表明,静水池溶解有机碳（DOC）和颗粒有机碳（POC）库储量平均值分别为5.69±2.90 mg·L^-1和24.56 ± 2.12 mg·L^-1;流水池DOC和POC分别为9.61±3.17 mg·L^-1和24.13 ±2.91 mg·L^-1.流水池和静水池TOC、DOC和POC的比例分别为 1∶0.75∶0.25和1∶0.82∶0.18.POC含量高的池塘DOC含量也较高.流水池的POC、DOC周日变动幅度大,静水池昼夜变动幅度小.流水池POC含量白天(5:00～17:00)升高,静水池降低,夜间(15:00～23:00)两池POC含量均降低.从23:00至次日5:00上升,两池分别在17:00和5:00达到高峰.白天(5:00～17:00) 流水池DOC/POC升高,静水池降低;夜间(17:00～23:00)两池均上升,23:00 至次日5:00则呈下降趋势.     

Limnological studies of and primary production in temple pond ecosystems

Three temple ponds with permanent blooms of blue green algae were highly productive. They all showed high alkalinity, hardness, electrical conductivity and pH. Organic carbon and nitrogen were highest in Sarvatheertham pond—60 to 79.6 mg./l. C and 4.10 to 7.60 mg./l. N. In Tamaraikulam it was 16.5 to 20.3 mg. C/l. and 1.03 to 1.32 mg. N/l. In Sarvatheertham, the gross production ranged from 2.85 to 20.72 g. O₂/m.²/d. Self shading by blanket algae of blue greens reduced productivity in Sarvatheertham, where a persistent thermal and biochemical stratification was noted. Very high organic carbon and nitrogen contents were noted in Sarvatheertham pond. The dry weight of plankton in this pond ranged from 430 to 900 mg./l. Productivity computed from diurnal changes in alkalinity and dissolved oxygen also revealed a high rate in Ayyankulam, Tamaraikulam and Sarvatheertham in descending order. Very wide fluctuations in pH, both diurnally and depth-wise, were recorded in Sarvatheertham and to a lesser extent in the other two ponds. Photosynthetic efficiency was 4.03% in Ayyankulam, 2.09% in Tamaraikulam and 1.56% in Sarvatheertham. By the diurnal oxygen curve method, a gross primary production of 97.5 g. O₂/m.²/d was recorded in Ayyankulam.     

Case study: design, operation, maintenance and water quality management of sustainable storm water ponds for roof runoff

The purpose of this case study was to optimise design, operation and maintenance guidelines, and to assess the water treatment potential of a storm water pond system after 15 months of operation. The system was based on a combined silt trap, attenuation pond and vegetated infiltration basin. This combination was used as the basis for construction of a roof water runoff system from a single domestic property. United Kingdom Building Research Establishment and Construction Industry Research and Information Association, and German Association for Water, Wastewater and Waste design guidelines were tested. These design guidelines failed because they did not consider local conditions. The infiltration function for the infiltration basin was logarithmic. Algal control techniques were successfully applied, and treatment of rainwater runoff from roofs was found to be largely unnecessary for recycling (e.g., watering plants). However, seasonal and diurnal variations of biochemical oxygen demand, dissolved oxygen and pH were recorded.     

崇明东滩堤内次生人工湿地冬季水鸟的夜间行为

2006年11月中旬至2007年2月中旬,以崇明东滩堤内次生人工湿地(鱼蟹塘)为主要研究区域,对8种水鸟越冬期夜间行为进行了连续观察。结果发现,斑嘴鸭(Anas poecilorhyncha)、绿头鸭(A.platyrhynchos)、银鸥(Larus argentatus)及白鹭(Egretta garzetta)等白天在塘内栖息和取食的水鸟,黄昏时飞离并栖息于堤外海滩或堤内农田和防护林,次日清晨飞回。夜间停留在鱼蟹塘的水鸟活动差异性显著。其中,夜鹭(Nycticorax nycticorax)白天栖息于堤内防护林,夜间17:00～17:30时后飞入鱼蟹塘,分散于塘内光滩及芦苇附近活动,在约23:30时后其行为以觅食为主,达70%以上。黑水鸡(Gallinula chloropus)和骨顶鸡(Fulica atra)活动频繁,主要分布于芦苇丛和周边水域,21:30～次日2:30时其觅食行为达到高峰,数量占60%～90%,2:30～3:30时后转为以休息为主。而白天活动频繁的小(Tachybaptus ruficollis)夜间停留在塘内,主要休息于水位较深区域。结果表明,越冬水鸟夜间行为具多样性,可能与昼间活动模式有关。     

The vertical distribution of some ciliated Protozoa in the plankton of a eutrophic pond during summer stratification

The vertical distribution of some ciliated Protozoa in the plankton of a pond in north-west England was investigated during August 1971. At this time, when the pond was stratified with an oxygen dificient hypolimnion, ciliates were counted at 10-cm depth intervals every 5 h over 25 h. The most common species (Loxodes magnus and L. striatus) were confined to the hypolimnion; there was no diurnal migration into the epilimnion. Earlier work had shown that Loxodes species require oxygen; it is therefore possible that these ciliates, which inhabited the oxygen dificient hypolimnion, migratedvertically, from time to time, to an oxygen supply at the boundary with the well-oxygenated epilimnion. To test this, Loxodes populations were confined in cellophane tubese both in the hypolimnion (at 3 m) and epilimnion (0.5 m) for 12 and 24 h (earlier trials had shown that the tubes were not markedly toxic). The ciliates died at both depths, and in a further experiment when Loxodes were confined at 3 m and 0.5 m and sampled at 5-h intervals up to 25 h it was found that they survived longer in the hypolimnion. It is suggested that ciliatees confined at 3 m died because they were unable to migrate vertically to an oxygen supply, while those at 0.5 m died because some other adverse factor was operating in the eiplimnion. Laboratory experiments showed that Loxodes died inn water in which phytoplankton photosynthesis took place and it is suggested that side effects of photosynthesis in the epilimnion (e.g. a rise in pH) caused the death of ciliates exposed at 0.5 m.     

Spatial and temporal dispersion patterns of golden perch, Macquaria ambigua, larvae in an artificial floodplain environment

Golden perch larvae were stocked into a pond and inundated floodplain system in south-eastem Australia to determine movement patterns of the larvae onto and off the floodplain area. A total of 428 larvae were caught moving from the floodplain into the pond whereas only 18 were collected moving in the reverse direction. Thirty one larvae were caught at open water sites in the pond and floodplain, but only three were collected from sites on the floodplain which provided shade, timber or water flow. Transect samples from the pond also yielded more larvae than samples from floodplain transects, indicating a distinct spatial dispersion pattern in favour of the pond.
Spatial dispersion patterns of golden perch larvae appear to correspond with gradients in water quality between the pond and floodplain habitats. Stratification occurred in the pond but did not develop on the floodplain. Water on the floodplain was cooler, harder and contained less oxygen than surface water from the pond. Die1 oscillations occurred in water temperature, pH, dissolved oxygen, carbon dioxide and acidity, but there was no significant corresponding pattern in the distribution of larvae.
Dispersion of golden perch larvae between pond and floodplain habitats is not random, and may be actively influenced by local-scale variations in water quality.     

Diurnal bottom feeding of predator fish strengthens trophic cascades to benthic algae in experimental flow-through pools

Mechanisms that determine the strength of trophic cascades from fish to benthic algae via algivorous invertebrates in stream communities have not been clarified. Using seven fish species, we tested the hypothesis that the interspecific variation of predatory behavior of fishes affects the strength of trophic cascades in experimental streams. One or two species of fish were introduced into flow-through pools of 2.5 m² and the abundances of benthic invertebrates and algae were monitored. Pike gudgeon, a diurnal benthic feeder, triggered a strong trophic cascade but masu salmon, a diurnal drift feeder, did not have a cascading effect. Japanese dace, which is both a diurnal benthic and drift feeder, increased the algal biomass, but the nocturnal benthic feeder cut-tailed bullhead had little cascading effect. The diurnal benthic feeder silver crucian carp also had a cascading effect, but no trophic cascade was triggered either by Asian pond loach or by Japanese common catfish, both of which are nocturnal benthic feeders. Thus, diurnal benthic fish exerted a stronger cascading effect than diurnal drift feeders or nocturnal fish. The combination of two fish species enhanced the per-capita strength of trophic cascades, probably because one of the two species, the benthic feeder, preyed on more invertebrates than in the single-species pools.     

Diurnal habitat segregation by tadpoles in two temporary ponds in an Atlantic Rainforest remnant, Northeastern Brazil

Tadpoles are found in diverse aquatic habitats, where they share resources in various dimensions. Tadpole assemblages were studied in two temporary ponds in Atlantic Rainforest. Our aim was to analyze the temporal and spatial distribution patterns and their correlation with abiotic factors. Tadpoles were sampled weekly using nets, from March to December 2008. Samples were collected during the day and at night, and taken near the shore and in the centre of the ponds. Samples in inshore and pond centres were taken from both areas with and without aquatic vegetation. The assemblage consisted of 15 species in pond A and 12 species in pond B. The majority of species was accidental, and used the pond continuously. The assemblage was predominantly diurnal, which may be related to greater activity rate. In pond A the tadpoles primarily used the centre of ponds, whereas in pond B tadpoles primarily used shore areas. However, some populations showed preferences for particular environments. In pond A, environmental heterogeneity in the centre had the greatest influence on tadpole abundance. Our data suggest that temporal distribution facilitated the coexistence of different species of tadpoles in the pond but this conclusion is tentative and requires verification. Hence, more data needs to be collected so that we can propose effective area management plans.     

Soybean nodule gas permeability,nitrogen fixation and dirunal cycles in soil temperature

While diurnal cycles in nitrogen fixation rates are sometimes assumed to result from diurnal variation in photosynthetically active radiation, contradicting evidence exists that indicate soil temperature is the primary environmental influence. These studies assessed the significance of temperature on soybean nitrogen fixation under field conditions. Two groups of intact field-grown soybean plants, one at ambient and the other exposed to a 10°C diurnal variation in soil temperature, were nondestructively assayed for acetylene reduction rates. Activity was closely associated with soil temperature (R²=0.85), even when temperature was 12 h out of phase with ambient. Data were also obtained to determine if the effects of rhizosphere temperature on nitrogen fixation are mediated through an effect on the nodule oxygen permeability. Nodule oxygen permeability of intact, aeroponically grown soybean was closely correlated with the diurnal changes in temperature (R²=0.90).     

Comparison of methods to assess water column primary production in wetlands

We compared a number of techniques to measure water column autotroph production in a shallow, hypereutrophic wetland: diurnal oxygen changes; light and dark bottle incubations; chlorophyll a concentrations; daily changes in pH; and algal volume. Productivity from diurnal oxygen changes calculated at 0.25, 0.5, 1, 2, 3, and 4 h intervals give similar estimates, but not 12 h intervals (dawn-dusk-dawn). Net productivity in bottles was slightly lower than that indicated by diurnal oxygen changes, and gross productivity in bottles was much lower than diurnal changes. Changes in pH correlated well with gross and net productivity measurements, as well as algal volume. Chlorophyll a is correlated with diurnal and bottle net productivity measurements and pH changes, but not algal volume. Since daily pH flux and oxygen changes provide a better overall assessment of ecosystem processes than standing crop or bottle incubations, they could be useful measurements for ecological engineers interested in assessing the ecosystem function.     

Diurnal variations in the number of granulosa cells synthesizing DNA in relation to follicle size in the mouse ovary

Summary Autoradiographs of mouse ovaries prepared after pulse-labelling with ³H-thymidine at 4-hourly intervals over a 24-hour period show, that in the early stages of follicle development there is a diurnal variation in the number of granulosa cells synthesizing DNA. This is not found in later stages.The diurnal variations are correlated with low proliferation rates of the cell populations and with growth fractions below one.It is concluded, that diurnal variations in the number of granulosa cells synthesizing DNA are due to variations in the growth fractions of the granulosa cell populations.     

Seasonal change of protozoa and micrometazoa in a small pond with leaf litter supply

Protozoa and micrometazoa were observed in a small pond with leaf litter over a 2 year period. The total number of taxa observed in this pond was 83 protozoans and 30 micrometazoans, and the correspondence of each taxon and the habitats of surface water, leaf litter on the pond bottom and sedimented mud was noted. The microfauna in the litter on the pond bottom had a higher diversity than in the water or the sedimented mud. Patterns of seasonal change in the density of organisms — with one or two peaks in a year — were recognized in some taxa of protozoa and micrometazoa. Most peaks of bacterivorous protozoa in the leaf litter appeared in late autumn and spring. This phenomenon is considered to be closely related to the litter decomposition, because reduction of dissolved oxygen and/ or high bacterial density were observed in these two seasons. Nineteen species of protozoa from this pond were cultured in vitro with fallen leaves. From the results of the cultures and the observation of food vacuoles of protozoa in situ, part of the food web of the microfauna in the pond was estimated.     

Temperature and oxygen in an Everglades alligator pond

The Everglades is a large subtropical marsh ecosystem. Ponds, maintained through the activity of alligators, are abundant and ecologically important components of this system. Temperature in a 18 x 12 m study pond was controlled primarily by ambient air temperature, with significant temporal lags because of thermal resistance caused by plant growth. Temperature changed seasonally being 10° to 15°C lower in summer than winter. Diurnal temperatures fluctuated 7°C in summer and 4°C in winter. Maximum temperature exceeded 34°C. Dissolved oxygen fluctuated between 50 to 85% saturation in winter to supersaturation in summer. During the dry season water levels fell and oxygen fluctuated markedly, for example from 4 to 200% saturation within a diurnal cycle.The relation of water temperature to air temperature was similar to other reported ponds but continued fluctuation in winter differed from some results from other ponds. The distinct seasonality has important effects on biological components. Fluctuation of dissolved oxygen can result from high animal density and plankton in the dry season and can lead to massive mortality of aquatic animals. The physio-chemical conditions of Everglades alligator ponds are controlled by a combination of seasonal temperature and insolation, water level changes and biologic factors such as fish density, bird predation and alligator activity.     

The production of hemoglobin by small pond Daphnia pulex: intraspecific variation and its relation to habitat

SUMMARY.

• 1 Hemoglobin production was measured for two populations of Daphnia pulex, one from a temporary pond (GR Pond) and one from a permanent pond (Rash Pond). Surface water in Rash Pond remains high in oxygen, while by late summer very little oxygen remains in GR Pond. Hemoglobin synthesis was induced in the laboratory by artificial oxygen deficiency.
• 2 Reproductive state influenced the level of hemoglobin in Daphnia. Females with parthenogenesis eggs had higher total body hemoglobin than ephippial females. Clutches laid by pale Daphnia immediately before exposure to low oxygen conditions were aborted. Offspring produced by hemoglobin-rich females later in the treatment survived.
• 3 Hemoglobin production was higher for Rash Pond Daphnia. Visual predators exist in GR Pond, but are absent in Rash Pond. Also, Daphnia are smaller in GR Pond. Visual predation may have selected against high levels of hemoglobin in the temporary pond. Thus oxygen availability in nature is not necessarily a good predictor of hemoglobin production by Daphnia.
• 4 Feeding behavior was altered in low oxygen conditions. Browsing was dominant in low oxygen treatments while Daphnia in control treatments filtered algae normally. Browsing may increase access to sedimented iron necessary for hemoglobin synthesis.

     

Annual Abundances, Diversity and Growth Potential of Gymnamoebae in a Shallow Freshwater Pond

ABSTRACT. Abundance and diversity of gymnamoebae were assessed at monthly intervals for one year in the sediment surface layer of a shallow, highly productive, freshwater pond located in northeastern United States using laboratory culture enumeration techniques. The range in total abundance was 81/ml in January to 1,568/ml in June (spring peak) and 1,813/ml in October (autumn peak). The latter is equivalent to over 1.8 million per liter, one of the highest values reported for gymnamoebae from a freshwater pond. Maximum diversity (H = 3.3) occurred in April, July, and August. The growth potential of the gymnamoebae was determined in laboratory cultures (20° C) containing only the pond water (control culture) and pond water emended with malt-yeast extract and glucose (nutrient culture) using pond water collected in December. The total abundance of gymanmoebae increased from 363/ml in the initial pond water sample to approximately 1,800/ml in each of the culture conditions in the first week. Therafter, abundances reached 5,678/ml (control culture) and 8,016/ml (nutrient culture) by the third week indicating the vigorous growth potential from winter standing stock.