Download Acid rain

4/16/2013
WFS 433
Wade GeFellers
4.16.2013
I.
Define acid precipitation
II.
Look at how acid precipitation affects the environment
III. Look at how acid precipitation affects amphibians
IV.
Future of amphibians with acid precipitation
 Precipitation in the form of rain, snow, hail, dew, or fog that transports sulfur and nitrogen compounds from the atmosphere to the ground.(Likens 2012)
Source: http://www.omicspublishinggroup.net
1
4/16/2013
 Sulfur dioxide (SO2) and nitrogen oxides (NO, NO2) are bi‐
products from burning fossil fuels. These react with water, oxygen, carbon dioxide, and sunlight to form sulfuric and nitric acids and once
they reach the ground the acids change the chemistry within the environment. (Likens 2012)
Source: http://neftegaz.ru/images/00vtl00(4).jpg
 pH scale runs from 0 to 14
 pH <5.0 (Wells 2007)
Source: http://www.epa.gov
 Not limited to region of source
 Chemicals can be windblown across county, state, and continental boundaries  hundreds of miles (Liken 2012)
Source: http://www2.cnrs.fr/en/1943.htm
2
4/16/2013
 Acidification of water (streams, ephemeral pools, ponds, and lakes) and soil
 Immobilization and toxification of aluminum and other heavy metals (The Wildlife Society 2009)
 Acidification of previously non‐acidic habitats
 Ephemeral ponds/pools are typical habitat and breeding sites
 In North America alone ~ 50% of all frogs and ~33% of all salamanders reproduce in small ephemeral ponds.  Periodically dry and refill with fresh precipitation only
 Small watersheds  precipitation has little contact time with soils for buffering.
 Temperate species often breed immediately after spring thaw  surge of acid
water from snow pack. (Pierce 1993)
 All stages of life
 Eggs/embryos
 Larvae
 Adults 3
4/16/2013
 Direct toxic effects
 Fertilization external (spermatophores technically included) so sperm is in contact with acidic environment.
 Slightly acidic  reduce sperm motility
 Highly acidic  sperm disintegrate
 Very low pH  Development ceases within hours
(Pierce 1993)
 Moderate pH  Perivitelline shrinks and constricts embryo within egg capsule (“curling defect”)
 Some develop but are unable to hatch  inhibition of hatching enzyme.
 If they do hatch, usually exhibit developmental abnormalities bent tails and crooked vertebral column
 Delayed hatching times
(Pierce 1993)
 Adversely affects osmoregulation
 Substantially increasing rates of sodium ion loss through the skin and inhibiting the active uptake of sodium from the water. (Wells 113)
 Metamorphosis is hindered due to acid stress
 Often do not metamorphose before the pond dries. (Freda 1986)
4
4/16/2013
 Growth inhibited, even with short term exposure (3 days)
 timing of metamorphosis
 susceptibility of predation
 competition with larvae of other species
 size at metamorphosis
 survival in terrestrial environment
 timing and success of future reproduction
Inhibition of larval growth may be most pronounced effect on amphibian populations
(Pierce 1993)
 Once thought not to effect adults
 Recent studies show adult salamanders exposed to acidic soil show similar signs of acid stressed larvae.
 Lose both sodium and water from body at low pH.
(Pierce 1993)
 Community composition (Pierce 1993)
 Available food sources (Girardeau)
 Depletes food sources of tadpoles
 Kills zooplankton and algae
 Robs ponds of nutrients
 Deprives developing tadpoles of food
 Depletes food sources of adults
 Insects decline due to lack of plant food, so do the frogs and toads.
 Overall amphibians decline
5
4/16/2013
 Golden toad  Harlequin frog
Source: http://www.global‐greenhouse‐
warming.com/extinct‐golden‐toad.html Source: http://sofyteawesome.files.wordpress.com/
2011/11/harlequin_frog.jpeg
No direct mortality, but thought acidification could have played a role. (Pounds et. al 1994)
 Acid precipitation occurs worldwide
 Acid precipitation affects every life stage of both terrestrial and aquatic amphibians living in acid prone areas.
 Acid precipitation can change community A id i it ti h
it composition and essentially whole ecosystems.
 Acid precipitation depletes food sources, even those amphibians able to withstand some acidification.  Overall, every one of these factors combine to create the worst case scenario for all amphibians worldwide!
Final Position Statement: Acid Deposition. The Wildlife Society, Sept. 2009. Web. 14 Apr. 2013. <http://joomla.wildlife.org/documents/positionstatements/30‐
Acidic%20Deposition.pdf>. Freda, Joseph. "THE INFLUENCE OF ACIDIC POND WATER ON AMPHIBIANS: A REVIEW." Water, Air, and Soil Pollution 30.1‐2 (1986): 439‐50. Google Scholar. Web. 14 Apr. 2013. Girardeau, Laura. "Solving the Mystery of Amphibian Decline." Amphibians and Reptiles of Oregon. Ed. Tom Titus. The University of Oregon, n.d. Web. 14 Apr. 2013. Likens, G. Acid Rain. Ed. W Davis. National Atmospheric Deposition Program, 2012. Web. 14 Apr. 2013. <http://nadp.sws.uiuc.edu/educ/acidrain.aspx>. Pierce, Benjamin A. "The effects of acid precipitation on amphibians." Ecotoxicology
2.1 (1993): 65‐77. Google Scholar. Web. 14 Apr. 2013.
Wells, Kentwood D. The Ecology and Behavior of Amphibians. London: The University of Chicago Press, 2007. 843. Print.
6
4/16/2013
7