Laboratory investigations on the role of sediment surface and groundwater chemistry in transport of bacteria through a contaminated sandy aquifer

1992 ◽  
Vol 26 (7) ◽  
pp. 1410-1417 ◽  
Author(s):  
Martha A. Scholl ◽  
Ronald W. Harvey
Keyword(s):  
Groundwater Chemistry ◽  
Sediment Surface ◽  
Laboratory Investigations ◽  
Sandy Aquifer ◽  
Surface And Groundwater ◽  
Transport Of Bacteria

The Role of Ecopedological Parameters in Management Sustainability of Banat Lands

2018 ◽  
Vol 69 (3) ◽  
pp. 688-692
Author(s):  
Lucian Nita ◽  
Dorin Tarau ◽  
Gheorghe Rogobete ◽  
Simona Nita ◽  
Radu Bertici ◽  
...  
Keyword(s):  
Plant Nutrition ◽  
Physical State ◽  
Agricultural Land ◽  
Soil Characteristics ◽  
South West ◽  
Short And Long Term ◽  
Laboratory Investigations ◽  
Case Basis

The issue addressed relates to an area of 1891694 ha of which 1183343 ha are agricultural land (62, 56) located in the south-west of Romania and refer to the use of soil chemical and physical properties as an acceptor for certain crop systems, with minimal undesirable effects both for plants to be grown, as well as soil characteristics and groundwater surface quality. It is therefore necessary on a case-by-case basis, measure stoc or rect the acidic reaction by periodic or alkaline calculations, the improvement of plant nutrition conditions through ameliorative fertilization and the application of measures to improve the physical state, sufficient justification for the need to develop short and long term strategies for the protection and conservation of edifying factors and the need to respect the frequency of field and laboratory investigations at all 8x8 km grids of the National Soil-Grounds Monitoring System (organized by I.C.P.A.) and completing it with the relevant pedological and agrochemical studies.

Multiple interactions in riverine biofilms - surfactant adsorption, bacterial attachment and biodegradation

1995 ◽  
Vol 31 (1) ◽  
pp. 61-70 ◽  
Author(s):  
Graham F. White
Keyword(s):  
Organic Pollutants ◽  
Bacterial Attachment ◽  
Solid Surfaces ◽  
Sediment Surface ◽  
Liquid Interfaces ◽  
Polluted Soils ◽  
Biofilm Bacteria ◽  
The Impact ◽  
Multiple Interactions

Many organic pollutants, especially synthetic surfactants, adsorb onto solid surfaces in natural and engineered aquatic environments. Biofilm bacteria on such surfaces make major contributions to microbial heterotrophic activity and biodegradation of organic pollutants. This paper reviews evidence for multiple interactions between surfactants, biodegradative bacteria, and sediment-liquid interfaces. Biodegradable surfactants e.g. SDS, added to a river-water microcosm were rapidly adsorb to sediment surface and stimulated the indigenous bacteria to attach to the sediment particles. Recalcitrant surfactants and non-surfactant organic nutrients did not stimulate attachment Attachment of bacteria was maximal when biodegradation was fastest, and was reversed when biodegradation was complete. Dodecanol, the primary product of SDS-biodegradation, markedly stimulated attachment. When SDS was added to suspensions containing sediment and either known degraders or known non-degraders, only the degraders became attached, and attachment accelerated surfactant biodegradation to dodecanol. These cyclical cooperative interactions have implications for the design of biodegradability-tests, the impact of surfactant adjuvants on biodegradability of herbicides/pesticides formulated with surfactants, and the role of surfactants used to accelerate bioremediation of hydrocarbon-polluted soils.

scholarly journals Glucocorticoids for treating paediatric pulmonary hypertension: a novel use for a common medication

2017 ◽  
Vol 27 (7) ◽  
pp. 1410-1412 ◽  
Author(s):  
Manish Aggarwal ◽  
Ronald Mark Grady
Keyword(s):  
Pulmonary Hypertension ◽  
Potential Utility ◽  
Inflammatory Drugs ◽  
Laboratory Investigations ◽  
Anti Inflammatory

AbstractLaboratory investigations have shown the role of inflammation in the pathogenesis of pulmonary hypertension and improvement after anti-inflammatory drugs. Despite these observations, reports on the use of steroids to treat pulmonary hypertension in humans are absent from the literature. In this article, we report the use of glucocorticoids in the treatment of two children with pulmonary hypertension, demonstrating its potential utility.

Hydrogeochemical controls on surface and groundwater chemistry in naturally acidic, porphyry-related mineralized areas, southern Rocky Mountains

2006 ◽  
Vol 25 (S1) ◽  
pp. 231-231 ◽  
Author(s):  
Philip L. Verplanck ◽  
D. Kirk Nordstrom ◽  
Geoff S. Plumlee ◽  
Richard B. Wanty ◽  
Dana J. Bove ◽  
...  
Keyword(s):  
Rocky Mountains ◽  
Groundwater Chemistry ◽  
Southern Rocky Mountains ◽  
Surface And Groundwater

Protozoa abundance, growth, and bacterivory in the water column, on sedimenting particles, and in the sediment of Halifax Harbor

1990 ◽  
Vol 36 (12) ◽  
pp. 859-863 ◽  
Author(s):  
James A. Novitsky
Keyword(s):  
Bacterial Community ◽  
Water Column ◽  
Sediment Surface ◽  
Metabolic Inhibitor ◽  
Optimum Conditions ◽  
Bacterial Populations ◽  
Protozoan Grazing ◽  
Large Numbers ◽  
Doubling Times

The role of protozoan grazing in controlling bacterial populations was examined in four microbial habitats in Halifax Harbor, Canada: the water column, setting particles, the sediment–water interface, and the sediment. Large numbers of protozoans were found in all habitats although most (>56%) were small (<5 μm) flagellates. Protozoans larger than 10 μm were rarely observed; protozoans >20 μm were never observed. Protozoans were also observed to a depth of 9 cm below the sediment surface although efforts to culture viable protozoa failed except for the top 1 cm. The use of the metabolic inhibitor cycloheximide with and without colchicine to selectively inhibit eucaryotic metabolism was shown to severely affect procaryotic metabolism in sediment (and presumably particle and water) samples. Using fluorescently labelled bacteria as food, and under optimum conditions, up to 42% of the Protozoa population exhibited active grazing within 7 h. Using protozoan and bacterial community sizes and doubling times, it was calculated that each protozoan in Halifax Harbor would have to consume 13–118 bacteria per hour for the enumerated nanoplanktonic (<20 μm) Protozoa to be the sole control of the size of the bacterial community. Key words: marine, Protozoa, bacterivory, particles, bacteria.

scholarly journals Oxycline oscillations induced by internal waves in deep Lake Iseo

2018 ◽  
Author(s):  
Giulia Valerio ◽  
Marco Pilotti ◽  
Maximilian Peter Lau ◽  
Michael Hupfer
Keyword(s):  
Internal Waves ◽  
Water Layer ◽  
Sediment Surface ◽  
Chemical Gradient ◽  
Deep Lakes ◽  
Deep Lake ◽  
Deep Waters ◽  
Basin Scale ◽  
First Time

Abstract. Lake Iseo is undergoing a dramatic de-oxygenation of the hypolimnion, representing an emblematic example among the deep lakes of the prealpine area that are, to a different extent, suffering from reduced deep water mixing. In the anoxic deep waters, the release and accumulation of reduced substances and phosphorus from the sediments is a major concern. Since the hydrodynamics of this lake was shown to be dominated by internal waves, in this study we investigate for the first time the role of these oscillatory motions on the vertical fluctuations of the oxycline, currently situated at a depth of around 95 m, where a permanent chemocline inhibits deep mixing by convection. Temperature and dissolved oxygen data measured at moored stations show large and periodic oscillations of the oxycline, with amplitude up to 20 m and periods ranging from 1 to 4 days. A deep dynamics characterized by larger amplitudes at lower frequencies is shown to be favoured by the excitation of second vertical modes in strongly thermally stratified periods and of first vertical modes in weakly thermally stratified periods, when the deep chemical gradient can support baroclinicity anyhow. These basin-scale internal waves cause in the water layer between 85 and 105 m depth a fluctuation of the oxygen concentration between 0 and 3 mg L−1 that, due to the bathymetry of the lake, changes the redox condition at the sediment surface. This forcing, involving about 3 % of the lake's sediment area, can have major implications for the biogeochemical processes at the sediment water interface and for the internal matter cycle.

scholarly journals A CLINICAL STUDY ON THE ROLE OF ERANDA KSHARA IN STHAULYA (OBESITY)

2015 ◽  
Author(s):  
*Borse Vilas Pundlikrao ◽  
Bhaskare Sunil A ◽  
Pawar Kiran Bhikaji ◽  
Meshram Dnyaneshwar Sudhakar
Keyword(s):  
Clinical Study ◽  
Waist Circumference ◽  
Duration Of Treatment ◽  
Average Percentage ◽  
Waist Hip Ratio ◽  
Arm Circumference ◽  
Laboratory Investigations ◽  
Basic Concepts

There are so many basic concepts in Ayurveda; Dhatvagni mandya is one of them. The whole phenomenon of disease cannot be completed without Dosha-Dushya Siddhant. They play important role in the pathology of disease. Obesity is one of them, which affect the health as well as life span. Sthaulya is one of the disease which is known to mankind since Vedic era, has been dealt in great details in Ayurvedic texts. The sign, symptoms and etiological factor of Sthaulya show very much resemblance with obesity. Worldwide Obesity is emerging health problem. It is a metabolic disorder which has affected every corner of world. In present study 30 patients of Sthaulya were selected from OPD and IPD of M.A. Podar hospital, Mumbai. These patients were undergone throw laboratory investigations. They were treated with Eranda Kshara with Ghrita bharjit Hingu given orally, duration of treatment was two months and follow up was done with parameters like Height, weight, BMI, Mid arm circumference, Waist circumference, Waist Hip ratio and symptoms of Sthaulya. It was observed that Atikshuda and Atitrushna reduce significantly. It shows relief in weight, BMI, Waist Circumference, Mid Arm Circumference and Waist Hip ratio. There was no significant change in hematological as well as Urine investigations. Average percentage of relief was 60.72%. 

scholarly journals The role of groundwater characteristics in catchment recovery from nitrate pollution

2012 ◽  
Vol 43 (5) ◽  
pp. 560-575 ◽  
Author(s):  
S. M. Dunn ◽  
W. G. Darling ◽  
C. Birkel ◽  
J. R. Bacon
Keyword(s):  
Dispersion Model ◽  
Age Dating ◽  
Groundwater Transport ◽  
Transit Times ◽  
Groundwater Samples ◽  
Nitrate Concentrations ◽  
Groundwater Dating ◽  
Different Levels ◽  
Surface And Groundwater

The effectiveness of measures to mitigate nitrate concentrations in surface and groundwater depends not only on their suitability for reducing nitrate leaching, but also on characteristics of groundwater transport that may cause a lag in achieving recovery. The recovery of a catchment within a Nitrate Vulnerable Zone in the east of Scotland has been assessed using a combined monitoring and modelling approach. Understanding of the dominant hydrological processes was developed through a programme of monitoring of surface and groundwater bodies. Age dating of groundwater samples, using dissolved atmospheric trace gases (CFCs and SF6) underpinned the conceptualisation of groundwater transport and a lumped dispersion model was applied to the data to estimate mean solute transit times. High spatial variability in the groundwater dating made it difficult to estimate catchment means, but the range was estimated to lie between 15 and 60 years. A catchment hydrology and nitrate model was used to explore the effect of simple changes in land management on reducing nitrate concentrations, as well as associated time scales of recovery. The study has helped improve understanding of the role of groundwater in catchment recovery and given an indication of the scale of agricultural changes required to achieve different levels of pollution mitigation.

The role of epiphytic and epibenthic algal productivity in a tropical seagrass, Syringodium isoetifolium (Aschers.) Dandy, community

1993 ◽  
Vol 44 (1) ◽  
pp. 141 ◽  
Author(s):  
PC Pollard ◽  
K Kogure
Keyword(s):  
Algal Community ◽  
Sediment Surface ◽  
Leaf Production ◽  
Net Productivity ◽  
Multidisciplinary Study ◽  
Bare Sediment ◽  
Carbon Transfer ◽  
Algal Productivity ◽  
Syringodium Isoetifolium

The overall aim of this study, which was part of a multidisciplinary investigation, was to evaluate the role of epiphytic and epibenthic algae in a tropical seagrass, Syringodium isoetifoliurn (Aschers.) Dandy, community. Algal biomass (chlorophyll a) and productivity were determined over 20 days. The rates of photosynthesis were measured with both gas (oxygen) release and H14CO3 incorporation techniques. The photosynthetic characteristics of the algal community are described by the relationship between the rates of photosynthesis and irradiance (PI curve). The saturating light intensity (Ik), determined in the laboratory, was 240 �E m-2 s-1 (1 �E= 1 �mol). However, the maximum rate of net epibenthic production (Pmax) in situ of 2 g C g chla-1.h-1 was reached only at light intensities above the leaf canopy of more than 480 �E m-2 s-1 because of shading. The photoperiod (the period when algae were at Pmax was determined from the daily light profiles and used to calculate the mean net productivity of the epibenthic (4.2 g C m-2 day-1) and epiphytic (11.5 g C m-2 day-1.) algae during the study. The net epiphytic and seagrass productivities were equal and positively correlated (slope = 1.0; r2 = 0.92). However, the net seagrass leaf production was only 25% of the total seagrass net production. Most of the seagrass production appeared to be directed elsewhere, possibly into the below-ground tissue. Epiphytic algae accounted for more than four times the above-ground primary production. Compared with the bare sediment surface, the dense seagrass stand afforded 27�4 (s.d.) times more surface area on which the epiphyton could colonize. Thus, seagrasses provided the surfaces essential for maintaining the substantial epiphytic primary productivity, a passive but nonetheless important role. We compare our findings with other results of the multidisciplinary study and construct a carbon budget from which we infer a model of carbon transfer through this ecosystem. The algae were quantitatively the most important of the primary producers, seeming to provide most of the organic carbon to the higher trophic groups, at least for the period of this study.

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