The Dangers of Deicing

By Ashley E. Rhodes

Abstract

Loss of species richness is often due to anthropogenic activity. The global decline of amphibians is one such example. This case study examines the impact of road deicing agents on amphibians living near bridges and roads treated heavily with salt during the winter months. Concepts explored in this case include changes to the aquatic environment as a result of road deicing applications, bioaccumulation, osmoregulation in amphibians living in clean freshwater, and the impact of increased aquatic salinity levels on the ability of amphibians to adequately osmoregulate in an environment for which they are not adapted. Three short videos created by the author can be shown in class or assigned for viewing in advance for a "flipped" classroom approach. Originally developed for a general education/introductory biology course, the case could also be used with introductory level animal anatomy and physiology courses as part of a deeper exploration of the renal system.

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Date Posted

03/11/2016

Overview

Objectives

Describe the "ideal" habitat of an aquatic amphibian in regards to the osmolarity of the water in which it lives.
Explain how aquatic amphibian kidneys are designed to function when living in clean freshwater.
Relate specific renal system structures to particular osmoregulatory processes in specific environments.
Hypothesize about the challenges that aquatic amphibian kidneys must handle when the animal sits in clean freshwater, and how its specific nephron components have evolved to handle these challenges.
Describe how the application of deicing agents changes the "ideal" environment of an aquatic amphibian.
Hypothesize about the new challenges placed on aquatic amphibian kidneys when the environment changes as the result of the application of deicing agents.
Predict what happens to the osmolarity of aquatic amphibians' body fluids if they remain in an environment that has been tainted by runoff from roads treated with deicing agents.
Explain how aquatic amphibian nephrons can actually contribute to the problems encountered when the animal is exposed to water tainted with deicing agents.
Examine the differences between the renal system structures required for living in habitats such as terrestrial, freshwater, and marine biomes.
Hypothesize how very specific adaptations for one environment can work against an animal when its environment changes quickly.

Keywords

Amphibian; osmoregulation; anthropogenic activity; deicing; salt; renal system; kidney; osmosis; diffusion; osmolarity; runoff; nephron; loops of Henle

Subject Headings

Aquaculture

Biology (General)

Climatology / Meteorology

Developmental Biology

Earth Science

Ecology

Environmental Engineering

Environmental Science

Evolutionary Biology

Hydrology

Natural Resource Management

Physiology

Toxicology

Wildlife Management

Zoology

EDUCATIONAL LEVEL

Undergraduate lower division, Undergraduate upper division

FORMAT

PDF

TOPICAL AREAS

Policy issues, Regulatory issues

LANGUAGE

English

TYPE/METHODS

Flipped, Interrupted

Teaching Notes & Answer Key

Teaching Notes

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Answer Key

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Materials & Media

Supplemental Materials

Videos

The Process of Osmoregulation
This video provides an overview of how the renal system, specifically the nephrons, accomplish the process of creating urine while conserving important molecules like amino acids and glucose. Running time: 3:30 min. Created by Ashley E. Rhodes for the National Center for Case Study Teaching in Science, 2015.
Freshwater Adaptations
This video expands upon the Process of Osmoregulation video by explaining the adaptations freshwater vertebrates, specifically amphibians, have adapted as a result of living in an environment with a low osmolarity. Running time: 1:19 min. Created by Ashley E. Rhodes for the National Center for Case Study Teaching in Science, 2015.
Deicing Alters Freshwater Environments
This video explains why alterations to freshwater vertebrates’ environments, specifically those changes brought about by deicing, are so devastating. Running time: 1:27 min. Created by Ashley E. Rhodes for the National Center for Case Study Teaching in Science, 2015.