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Water Quality: A rating of a body of water based on measurable physical, chemical, and biological characteristics.

Water Quality Analysis via Indicator Organisms

JoVE 10025

Source: Laboratories of Dr. Ian Pepper and Dr. Charles Gerba - Arizona University
Demonstrating Author: Luisa Ikner

Water quality analysis monitors anthropogenic influences such as pollutants, nutrients, pathogens, and any other constituent that can impact the water’s integrity as a resource. Fecal contamination contributes microbial pathogens that threaten plant, animal, and human health with disease or illness. Increasing water demands and strict quality standards require that water being supplied for human or environmental resources be monitored for low pathogen levels. However, monitoring each pathogen associated with fecal pollution is not feasible, as laboratory techniques involve extensive labor, time, and costs. Therefore, detection for indicator organisms provides a simple, rapid, and cost effective technique to monitor pathogens associated with unsanitary conditions.


 Environmental Microbiology

Spatial Multiobjective Optimization of Agricultural Conservation Practices using a SWAT Model and an Evolutionary Algorithm

1School of Environmental and Forest Sciences, University of Washington, 2Center for Agricultural and Rural Development, Department of Economics, Iowa State University, 3Department of Civil, Architectural, and Environmental Engineering, North Carolina A&T University, 4Iowa Geological and Water Survey

JoVE 4009


 Biology

Wastewater Irrigation Impacts on Soil Hydraulic Conductivity: Coupled Field Sampling and Laboratory Determination of Saturated Hydraulic Conductivity

1Department of Ecosystem Science and Management, Pennsylvania State University, 2Department of Geography and Environmental Sustainability, State University of New York, Oneonta, 3Department of Geology and Environmental Science, University of Pittsburgh

Video Coming Soon

JoVE 57181


 JoVE In-Press

Sampling, Sorting, and Characterizing Microplastics in Aquatic Environments with High Suspended Sediment Loads and Large Floating Debris

1Department of Physical and Environmental Sciences, Texas A&M University-Corpus Christi, 2Department of Earth and Atmospheric Sciences, Saint Louis University, 3Department of Oceanography and Coastal Sciences, Louisiana State University, 4Department of Biology, University of Central Florida

Video Coming Soon

JoVE 57969


 JoVE In-Press

Use of Chironomidae (Diptera) Surface-Floating Pupal Exuviae as a Rapid Bioassessment Protocol for Water Bodies

1Department of Entomology, University of Minnesota, 2Biology, Chemistry & Physics, and Mathematics Department, Northern State University, 3Environmental Analysis and Outcomes Division, Minnesota Pollution Control Agency, 4RMB Environmental Laboratories, Inc.

JoVE 52558


 Environment

Turbidity and Total Solids in Surface Water

JoVE 10015

Source: Laboratories of Margaret Workman and Kimberly Frye - Depaul University

Turbidity and total solids are related measurements addressing clarity of surface waters. Turbidity is an indirect measure of water clarity that determines the amount of light that can pass through the water. Total solids is a direct measurement of solid particles suspended in water determined by weight. High levels of turbidity and total solids are caused by soil erosion, waste discharge, runoff, or changes in ecological communities including algal growth or abundance of benthic organisms that can disrupt sediments up into the water. Higher levels of turbidity and suspended solids can lower water quality by absorbing heat causing an increase in water temperature and a decrease in oxygen levels (warm water holds less oxygen). These conditions can also cause a decrease in photosynthesis as less sunlight penetrates the water, making the water unable to support some aquatic life. Suspended solids can also clog gills, smother eggs, reduce growth rates, and disrupt microhabitats of many aquatic organisms. One method of measuring turbidity includes using a Secchi disk. A Secchi disk is a metal disk with alternate black and white quarters (Figure 1). It is attached to a rope that


 Environmental Science

Removal of Trace Elements by Cupric Oxide Nanoparticles from Uranium In Situ Recovery Bleed Water and Its Effect on Cell Viability

1Division of Physical Therapy, Department of Orthopedics & Rehabilitation, University of New Mexico, 2Department of Ecosystem Science and Management, University of Wyoming, 3School of Pharmacy, University of Wyoming, 4Department of Environmental and Radiological Health Sciences, Colorado State University, 5Center for Environmental Medicine, Colorado State University, 6College of Pharmacy, California Northstate University

JoVE 52715


 Environment

Regular Care and Maintenance of a Zebrafish (Danio rerio) Laboratory: An Introduction

1Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical sciences, Edith Cowan University, 2Centre for Clinical Research in Neuropsychiatry, Graylands Hospital, University of Western Australia, 3McCusker Alzheimer's Research foundation, 4School of Medicine and Pharmacology, University of Western Australia, 5Department of Molecular and Biomedical Sciences, University of Adelaide, 6School of Biomedical Sciences, Curtin University of Technology, 7School of Psychiatry and Clinical Neurosciences, University of Western Australia

JoVE 4196


 Biology

Bioindication Testing of Stream Environment Suitability for Young Freshwater Pearl Mussels Using In Situ Exposure Methods

1Faculty of Environmental Sciences, Czech University of Life Sciences Prague, 2T. G. Masaryk Water Research Institute, 3Department of Zoology and Fisheries, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague

Video Coming Soon

JoVE 57446


 JoVE In-Press

Isolation of Fecal Bacteria from Water Samples by Filtration

JoVE 10213

Source: Laboratories of Dr. Ian Pepper and Dr. Charles Gerba - Arizona University
Demonstrating Author: Luisa Ikner

The quality of water destined for use in agricultural, recreational, and domestic settings is of great importance due to the potential for outbreaks of waterborne disease. Microbial agents implicated in such events include parasites, bacteria, and viruses that are shed in high numbers in the feces of infected people and animals. Transmission to new and susceptible hosts may then occur via the fecal-oral route upon ingestion of contaminated water. Therefore, the ability to monitor water sources for the presence of pathogenic microorganisms is significant in order to ensure public health. Due to the sheer number and variety of potential fecal-oral pathogens that may be present in water and their variable concentrations, it is impractical and expensive to assay directly for each one of them on a regular basis. Therefore, the microbiological assays for water quality monitoring employ coliform indicator bacteria. Coliforms comprise, in part, the normal intestinal microflora of warm-blooded mammals, are non-pathogenic, and are consistently excreted in the feces. Therefore, the detection of coliform bacteria in water means that a fecal release occurred, and that harmful pathogenic m


 Environmental Microbiology

Nutrients in Aquatic Ecosystems

JoVE 10023

Source: Laboratories of Margaret Workman and Kimberly Frye - Depaul University

Nitrogen and phosphorus are essential plant nutrients found in aquatic ecosystems and both are monitored as a part of water quality testing because in excess amounts they can cause significant water quality problems. 

Nitrogen in water is measured as the common form nitrate (NO3-) that is dissolved in water and readily absorbed by photosynthesizers such as algae. The common form of phosphorus measured is phosphate (PO43-), which is strongly attracted to sediment particles as well as dissolved in water. In excess amounts, both nutrients can cause an increase in aquatic plant growth (algal bloom, Figure 1) that can disrupt the light, temperature, and oxygen levels in the water below and lead to eutrophication and hypoxia (low dissolved oxygen in water) forming a “dead zone” of no biological activity. Sources of nitrates and phosphorus include wastewater treatment plants, runoff from fertilized lawns and agricultural lands, faulty septic systems, animal manure runoff, and industrial waste discharge. Figu


 Environmental Science

The Portable Chemical Sterilizer (PCS), D-FENS, and D-FEND ALL: Novel Chlorine Dioxide Decontamination Technologies for the Military

1United States Army-Natick Soldier RD&E Center, Warfighter Directorate, 2Department of Molecular Biology and Biophysics, University of Connecticut Health Center, 3Lawrence Livermore National Laboratory, 4Children's Hospital Oakland Research Institute

JoVE 4354


 Bioengineering

Microinjection of CRISPR/Cas9 Protein into Channel Catfish, Ictalurus punctatus, Embryos for Gene Editing

1School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, 2Department of Animal Wealth Development, Faculty of Veterinary Medicine, Suez Canal University, 3Anatomy and Embryology Department, Faculty of Veterinary Medicine, Cairo University, 4Department of Molecular Physiology and Biophysics, Vanderbilt University, 5Life Science Institute, University of Michigan

JoVE 56275


 Genetics

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