Stability of pH, conductivity and alkalinity in dilute clear water samples exposed to various environmental conditions

2021 ◽  
Author(s):  
Espen Enge ◽  
Henrik van der Hoeven ◽  
Roald Kommedal
Keyword(s):  
Environmental Conditions ◽  
Water Samples ◽  
Clear Water

Comparative stability and growth requirements of S. aureus and faecal indicator bacteria in seawater

2006 ◽  
Vol 54 (3) ◽  
pp. 169-175 ◽  
Author(s):  
R.S. Fujioka ◽  
T.M. Unutoa
Keyword(s):  
Environmental Conditions ◽  
Water Samples ◽  
High Salinity ◽  
Indicator Bacteria ◽  
Nutritional Requirements ◽  
Recreational Waters ◽  
E Coli ◽  
Growth Requirements ◽  
Comparative Stability ◽  
Bactericidal Agent

The fate (stability, multiplication) of S. aureus, E. coli and E. faecalis was determined in three classes of recreational waters (seawater, estuarine, stream) supplemented with nutrients in the form of sewage and peptone. In the absence of sunlight (24±2 °C), all bacteria in all water samples did not multiply and were slowly (days) inactivated. When 50% sewage was added to all water samples, E. coli and E. faecalis multiplied but S. aureus did not. When peptone (0.05%, 0.5%) was the added nutrient, the three bacteria multiplied. In the presence of sunlight (15–27 °C), S. aureus was inactivated rapidly (hours) in all water samples. These results show that when their nutritional requirements are met, S. aureus, E. coli and E. faecalis can multiply in the high salinity conditions of seawater. However, under environmental conditions, sunlight is an effective natural bactericidal agent.

scholarly journals KEANEKARAGAMAN JENIS IKAN DI SUNGAI EMBALOH DESA BANUA UJUNG KECAMATAN EMBALOH HULU KABUPATEN KAPUAS HULU

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Odilo Noplantino Ajai ◽  
M Sofwan Anwari ◽  
M Dirhamsyah
Keyword(s):  
Species Diversity ◽  
Fish Species ◽  
Palm Oil ◽  
Environmental Conditions ◽  
Research Data ◽  
Survey Method ◽  
Clear Water ◽  
Selection Of ◽  
Fish Species Diversity ◽  
River Fish

The condition of Embaloh River is still well maintained, with clear water and a large variety of fishes. This is because the forest around Embaloh River is still dense; there is no deforestation, mining, and palm oil garden. In such a condition, the river is capable of maintaining a large variety of fishes that have not listed yet. Therefore, this research has the purpose of studying the variety of fishes in Embaloh River, and also to categorize the fishes based on their benefits, whether as decorative fishes, to be eaten, or even as a decorative fish and also to be eaten. The research was conducted on the Embaloh River, Banua Ujung Village, Embaloh Hulu District, Kapuas Hulu Regency. Research Data is obtained by the use of fishing equipment such as mesh, Bubu, Sauk, trawler, burst, and Talom. The method of research using the survey method, the selection of observation stations conducted with (purposive sampling) based on consideration of environmental conditions of the water. This location is made 3 (three) stations on the Embaloh River and 1 (one) station is on the lake (oxbow) called Lake Loane. Lake Loane is a stream of the Embaloh River Moreover, fish of species taken from Embaloh River and Loane Lake, which water from Embaloh River flows to, consist of several families of fish; Cobitidae (1 species), Cyprinidae (13 species), Elopidae (1 species), Grynocheilidae (1 species), Helostomatidae (1 species), Osphronemidae (2 species), Polynemidae (1 species), Pristolepididae (1 species), Sisoridae (1 species), and Syngnathidae (1 species).Keywords: Banua Ujung Village, Embaloh River, Fish Species Diversity, Loane Lake.

scholarly journals Struktur Komunitas dan Kelimpahan Fitoplankton dan Zooplankton pada Musim Penghujan di Zona Intertidal Pantai Selatan Yogyakarta

2021 ◽  
Vol 24 (2) ◽  
pp. 167-176
Author(s):  
Ratih Ida Adharini ◽  
Namastra Probosunu
Keyword(s):  
Community Structure ◽  
Environmental Conditions ◽  
Water Samples ◽  
Low Temperatures ◽  
Intertidal Zone ◽  
Rainy Season ◽  
Diversity Index ◽  
South Coast ◽  
Wet Season ◽  
Dominance Index

Plankton is an organism that plays an important role as a water food reserve, which is influenced by environmental conditions. This study aims to determine the community structure, abundance and biodiversity of phytoplankton and zooplankton in the intertidal zone of south coast of Yogyakarta during the rainy season. The research was conducted at Pantai Drini, Kukup, and Sundak of Gunungkidul District during December 2016 - February 2017. Sampling was conducted on three observation stations in the intertidal zone of Drini Beach, Kukup, and Sundak twice a month. The water samples were taken with plankton nets number 25, then were fluidized in 4% formalin and stored at low temperatures. The results showed diversity index of plankton in Kukup Beach in January at 1.86 while the lowest value in February at Sundak Beach was 0.87. The highest plankton abundance in January at Sundak Beach was 900 individu L-1 while the lowest value in December at Kukup Beach was 217.8 individu L-1. Based on the diversity index of Shannon-Wiener, intertidal coast waters of Yogyakarta in wet season is categorized as moderate, and dominance index is categorized  as low. Plankton merupakan organisme yang berperan penting sebagai cadangan makanan perairan dan dipengaruhi oleh kondisi lingkungan. Penelitian ini bertujuan untuk mengetahui struktur komunitas, kelimpahan dan keanekaragaman plankton pada zona inertidal pantai selatan Yogyakarta selama musim penghujan. Penelitian dilakukan di Pantai Drini, Kukup, dan Sundak Kabupaten Gunungkidul selama bulan Desember 2016 – Februari 2017. Pengambilan sampel dilakukan pada tiga stasium pengamatan di zona intertidal Pantai Drini, Kukup, dan Sundak setiap dua minggu. Sampel air diambil dengan jaring plankton nomor 25, kemudian sampel plankton difiksasi dalam formalin 4% dan disimpan pada suhu rendah. Hasil penelitian menunjukan indeks keanekaragaman jenis plankton tetinggi di Pantai Kukup pada bulan Januari sebesar 1,86 sedangkan nilai terendah pada bulan Februari di Pantai Sundak sebesar 0,87. Kelimpahan plankton tertinggi pada bulan Januari pada Pantai Sundak sebesar 900 individu L-1 sedangkan nilai terendah pada bulan Desember di Pantai Kukup yaitu 217,8 individu L-1. Berdasarkan indeks keanekaragaman Shannon-Wienner maka indeks keanekaragaman di pantai selatan Yogyakarta tergolong rendah-sedang dengan indeks dominansi tergolong rendah.

Identification of a Holocene aquifer–lagoon system using hydrogeochemical data

2014 ◽  
Vol 82 (1) ◽  
pp. 121-131 ◽  
Author(s):  
F. Sola ◽  
A. Vallejos ◽  
L. Daniele ◽  
A. Pulido-Bosch
Keyword(s):  
Multivariate Analysis ◽  
Water Chemistry ◽  
Coastal Lagoon ◽  
Environmental Conditions ◽  
Water Samples ◽  
Coastal Aquifer ◽  
Middle Holocene ◽  
Hydrogeochemical Modelling ◽  
Lagoon Environment ◽  
Good Agreement

AbstractThe hydrogeochemical characteristics of the Cabo de Gata coastal aquifer (southeastern Spain) were studied in an attempt to explain the anomalous salinity of its groundwater. This detritic aquifer is characterised by the presence of waters with highly contrasting salinities; in some cases the salinity exceeds that of seawater. Multivariate analysis of water samples indicates two groups of water (G1 and G2). Group G1 is represented in the upper part of the aquifer, where the proportion of seawater varies between 10 and 60%, whilst G2 waters, taken from the lower part of the aquifer, contain 60−70% seawater. In addition, hydrogeochemical modelling was applied, which reveals that the waters have been subject to evaporation between 25 and 35%. There was a good agreement between the modelled results and the observed water chemistry. This evaporation would have occurred during the Holocene, in a coastal lagoon environment; the resulting brines would have infiltrated into the aquifer and due to their greater density, sunk towards the impermeable base. The characteristics of this water enabled us to reconstruct the interactions that must have occurred between the coastal aquifer and the lagoon, and to identify the environmental conditions that prevailed in the study area during the Middle Holocene.

scholarly journals Faktor Biotik dan Abiotik pada Tempat Perkembangbiakan Anopheles spp. di Desa Gunung Jati, Kecamatan Pagedongan, Banjarnegara, Provinsi Jawa Tengah

2018 ◽  
pp. 153-162
Author(s):  
Dyah Widiastuti ◽  
Anggun Paramita Djati ◽  
Nova Pramestuti
Keyword(s):  
Light Intensity ◽  
Water Temperature ◽  
Environmental Conditions ◽  
Water Samples ◽  
Endemic Area ◽  
Abiotic Factors ◽  
Optimum Conditions ◽  
Malaria Endemic Area ◽  
Breeding Sites ◽  
Larvae Density

Malaria transmission in Gunung Jati Village, Banjarmegara needs serious attention because this village is malaria endemic area. This study aimed to investigate the biotic and abiotic environmental conditions at Anopheles spp. breeding sites in Gunung Jati village, Banjarnegara. Anopheles spp. larvae collection, measurement of abiotic factors and observation of microbiota on water samples were conducted on May 2015. Anopheles spp. larva was found  in puddles on the banks of the river with larvae density was 5 larvae per dip. Water temperature conditions in all breeding sites ranged from 26-32 oC, the degree of acidity was neutral, with varying light intensity. Synedra are the most commonly found algae from all observed breeding sites. The environmental conditions were in accordance with the optimum conditions that support the development of Anopheles spp. larvae

scholarly journals Microbiological vulnerability of eggs and environmental conditions in conventional and free-range housing systems

2018 ◽  
Vol 39 (1) ◽  
pp. 133 ◽  
Author(s):  
Julia Arantes Galvão ◽  
Alexander Welker Biondo ◽  
Fábio Sossai Possebon ◽  
Thiago Luis Belém Spina ◽  
Letícia Borges Nunes Correia ◽  
...  
Keyword(s):  
Food Safety ◽  
Animal Welfare ◽  
Environmental Conditions ◽  
Water Samples ◽  
Production Plant ◽  
Conventional System ◽  
Salmonella Spp ◽  
Standard Methods ◽  
Free Range ◽  
Housing Systems

Although Brazil is currently the world’s eighth largest egg exporter, the shift of consumers towards free-range eggs may present new sanitary challenges. This study aims to evaluate the microbiological vulnerability of eggs and environmental conditions in a farm certified for both conventional and free-range systems using two standard methods (enterobacteria counting and Salmonella spp. survey). Two high-producing farms were selected for this study, one under both conventional and free-range systems at the same place as the test farm, and another under conventional system only as a control farm. Enterobacteriaceae counts were determined for eggshells; and detection of Salmonella spp. was conducted in eggs, nest box material, feeder, and sponge samples from water dispensers, feeders, production plant, besides water samples from nipple dispensers and artesian well. The average enterobacteria count (log CFUmL-1) was 0.09 for conventional and 1.73 for free-range systems (p < 0.001). While Salmonella spp. was not detected in the conventional system but was present in one feeder and three eggshells from the free-range system. Therefore, the conventional system demonstrated better hygiene-sanitary status than the free-range one. Moreover, controlling food safety should always be considered when improving animal welfare.

scholarly journals Study on introduction of Cerasus clarofolia in Huangshan

2019 ◽  
Vol 131 ◽  
pp. 01126
Author(s):  
Cheng-hui Nan ◽  
Xiao-ming Xue ◽  
Chun-ping Xie ◽  
Xian-gui Yi ◽  
Xian-rong Wang ◽  
...  
Keyword(s):  
Survival Rate ◽  
Low Temperature ◽  
Environmental Conditions ◽  
Clear Water ◽  
Natural Conditions ◽  
Physiological Differences

In this paper, the habitat of Cerasus clarofolia was investigated and analysed, under natural conditions the growth of Cerasus clarofolia is influenced by low temperature of winter. The seeds of Cerasus clarofolia need low-temperature to germination. The seedling with 4 leaves grew well after introduction, the survival rate reached 79.7%. Planting with clear water was found easier to take roots, the roots were come from the lenticels, under diffent environmental conditions, the lenticels formed morphological, physiological differences are the important factors take roots for Cerasus.

scholarly journals Análisis de interferencia de parámetros físicos del agua, en desinfección por radiación UV

2016 ◽  
Vol 14 (2) ◽  
Author(s):  
Pedro Mauricio Acosta Castellanos ◽  
Carlos Andrés Caro Camargo ◽  
Néstor Rafael Perico Granados
Keyword(s):  
Escherichia Coli ◽  
Ultraviolet Radiation ◽  
Environmental Conditions ◽  
Water Samples ◽  
Evaluation Research ◽  
Uv Disinfection ◽  
Physical Parameters ◽  
Physical Factors ◽  
Static Test ◽  
Microbiological Parameters

<p>Este artículo presenta los resultados de investigación de la evaluación en la eficacia de la remoción de parámetros microbiológicos del agua por medio de radiación ultravioleta. Se hizo mediante ensayos estáticos en un banco de pruebas donde se irradiaron nueve muestras de agua, en las que se variaron las condiciones del medio y del agua. Los parámetros microbiológicos analizados fueron echerichia coli, coliformes totales y mesófilos.</p><p>Se analizaron las muestras de agua, a partir de variar de manera controlada sus parámetros físicos, los que influyen en la inactivación, como turbiedad, tiempo de exposición y volumen de agua tratada y concentración microbiológica. Se infirió cuáles son los factores físicos que más tienen influencia en la inactivación y se comprobó la importancia de tratamientos primarios previos a la desinfección por radiación ultravioleta.</p><p>Se construyeron las curvas dosis-respuesta de cada uno de los parámetros microbiológicos y su relación con el parámetro físico analizado. A partir de éstas se determinó la dosificación necesaria para la inactivación. Las muestras de agua fueron analizadas mediante los métodos de número más probable, sustrato definido y recuento en placa.</p><p>Abstract<br />This paper presents the results of evaluation research on the effectiveness of the removal of microbiological parameters water by ultraviolet radiation. It was made by a static test where nine water samples, in which environmental conditions and water were varied irradiated trials. The microbiological parameters analyzed were Escherichia coli, total coliforms and mesophilic.<br />Water samples were analyzed from controllably vary its physical parameters, which influence the inactivation, as turbidity, exposure time and volume of treated water and microbiological concentration. Inferred what physical factors that influence the importance of inactivation and prior to UV disinfection are primary treatments was tested.</p>

scholarly journals Efficiency of Sampling Sunfishes Using Snorkeling in Clear, Warm-Water Streams of the South-Central United States

2018 ◽  
Vol 9 (2) ◽  
pp. 602-609
Author(s):  
Robert Mollenhauer ◽  
Shannon K. Brewer
Keyword(s):  
Environmental Conditions ◽  
Cold Water ◽  
Warm Water ◽  
Low Flow ◽  
Stream Fish ◽  
Single Individual ◽  
Clear Water ◽  
Imperfect Detection ◽  
Water Stream ◽  
South Central

Abstract The continued evaluation of fish-sampling gears and methods is essential to identify their applicability across environmental conditions and among species. Although limited by visibility, snorkeling has potential advantages relative to other fish-sampling gears in wadeable streams (e.g., minimally intrusive, cost effective, and appropriate in deeper areas). Clear water is common to warm-water streams; however, the use of snorkeling for monitoring stream-fish populations has largely focused on cold-water systems. To assess relative snorkeling efficiency in warm-water streams, we compared standardized single-pass snorkel counts to tow-barge electrofishing abundance estimates for six sunfishes (Centrarchidae) in the Ozark Highlands ecoregion of northwest Oklahoma and southwest Missouri under relatively similar environmental conditions (i.e., clear water, cobble substrates, low-flow conditions). Snorkeling efficiency was variable among sunfishes and consistently low for species with cryptic traits and habitat use. We also did not detect cryptic sunfishes (i.e., a single individual was not encountered) using snorkeling at multiple stream reaches where estimated abundance was &gt; 50 within a 0.5- to 1.0-km stream reach. Our findings indicate that snorkeling has applications for monitoring sunfish populations and assemblages when using an abundance estimator or accounting for imperfect detection; however, it is inappropriate for estimating population size of cryptic sunfishes. We encourage continued research into the applicability of snorkeling to estimate warm-water stream fish abundance.

Assessment of Water Pollutants from Asphalt Pavement Containing Recycled Rubber in Rhode Island

1998 ◽  
Vol 1626 (1) ◽  
pp. 95-104 ◽  
Author(s):  
Pradeep Vashisth ◽  
K. Wayne Lee ◽  
Raymond M. Wright
Keyword(s):  
Water Quality ◽  
Rhode Island ◽  
Environmental Conditions ◽  
Water Samples ◽  
Quality Evaluation ◽  
Asphalt Pavement ◽  
Crumb Rubber ◽  
Water Quality Criteria ◽  
Water Quality Evaluation ◽  
Recycled Rubber

Use of recycled rubber in asphalt pavement has been widely accepted since it overcame the scrap tires disposal problem and it has many advantages—for example, savings in quantity and cost of construction materials. In this study, hot-mix asphalt (HMA) specimens with or without crumb rubber modifier (CRM) were analyzed under different environmental conditions. The CRM was added into HMA by two processes (wet and dry processes). The CRM was procured from two different sources to prepare specimens (one source for each process). Cylindrical specimens were tested in a particle entrainment system at two different temperatures and three different pH levels. Slab specimens were simulated for rainfall conditions. Water samples were collected in all three phases of the study: preliminary investigations on individual CRM, water quality evaluation for cylindrical HMA specimens at various environmental conditions, and water quality evaluation for slab HMA specimens under simulated rainfall conditions. Collected water samples were analyzed for six metals: chromium, lead, nickel, copper, cadmium, and zinc. A general trend for these metals indicates that zinc was leached in higher concentrations than other metals and all the metals were leached in higher concentrations at higher temperature (maximum asphalt pavement temperature) and at lower pH (pH 2.0 conditions). Finally, based on the limited scope of this effort and comparison with water quality criteria, there does not appear to be any evidence that there will be a detrimental effect on the environment or to human health.

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