Transcript Lian Liu presentation

A Comparative Study of Water Quality
and Aquatic Macroinvertebrate Diversity
in the Rio Grande and its Ditches
By Lian Liu
Mentor: Ayesha Burdett
Invertebrates As Indicators
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Invertebrate populations often used as way
to measure human disturbance and water
quality
Diversity is also an indicator of water quality
EPT (Ephemeroptera, Plecoptera,
Trichoptera) taxa common sign of good
water quality
Oligochaetes indication of poor water quality
Can this be applied to the Rio Grande?
The Burning Questions
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Will there be a significant difference between the
invertebrate diversity and abundance in the Rio
Grande compared to the ditches?
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Will these factors be dependent on vegetation type
or flow rate?
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Yes. The Rio Grande will have greater diversity and more
abundance.
Yes it will depend on both.
Are invertebrates actually a good indication of water
quality?
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Yes because they are directly affected by changes in
physicochemical properties
The Sites of Research
Salt Cedar
Russian Olive
River Sites
Willow
Ditch Sites
Willow
Salt Cedar
Russian Olive
Instruments and Materials
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A throw trap with an area of 45.72
cm X 45.72 cm was made
A meter stick
A dip net
Bottles for water samples and
specimen
70% Ethanol to preserve and kill
specimen
A dissecting scope
Taxonomic Keys
Procedure
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A water sample is taken and
chemical analysis done for
Nitrate and Phosphate
Then the water level is
measured
The throw trap is set
The throw trap is placed at
three different locations per
site
The dip net is used to sample
until no specimen are found
Then the specimen are IDed
to genus or family
Data Analysis
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ANOVA and regression were used to analyze
the relationship between variables
SPSS 17.0 was the program of choice
Intolerance values for macroinvertebrates
borrowed mostly from Hilsenhoff (1988)
Results
Mean Richness
Mean Abundance
An Idea of the Diversity
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No Plecoptera found
River had more Genera of EPT taxa than Ditch
Only Willow vegetation types had both Ephemeroptera and
Trichoptera genera
Salt Cedar overall lowest in richness
Overall Taxonomic Richness
Odonata
Diptera
Ephemeroptera
Trichoptera
Hemiptera
Coleoptera
Amphipoda
Decapoda
Isopoda
Oligochaeta
Polychaeta
Mollusca
Taxonomic Means
Mean Trichoptera
Mean Odonata
Baetidae: 4
Ephemerellidae: 1
Mean Ephemeroptera
Coenagrionidae: 9
Gomphidae: 1
Hydropsychidae: 3
Leptoceridae: 4
Taxonomic Means Cont.
Mean Chironomidae
Oligochaeta: 8
Mean Annelids
Blood Red Chironomidae: 8
Other Chironomidae: 6
Nitrate and Phosphate Levels
Depth and Flow
Flow vs. Mean Richness
Flow vs. Mean Abundance Logged
So What? A Discussion of the Results
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The results are inconsistent with the initial
hypothesis
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Some results were as expected
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The ditch was more taxonomically rich than the river though
not by much.
Nitrate and Phosphate levels were not correlated with
richness and abundance
River more rich in intolerant taxa while the ditch was more
rich in tolerant taxa
There was a difference between vegetation types
and abundance as well as richness
So What Does That Mean?
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The ditch and river contain two distinct
communities of macroinvertebrates
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The ditch has harsher living conditions
compared to the river.
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Salt cedar sites have communites of low
taxonomic richness and abundance.
Relating the Results and Further
Research
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Vegetation types and not just the water itself can
impact the abundance and richness of an aquatic
environment
Though communities at different site types can be
different it does not mean richness is lost
For further research more water chemistry such as
pH and salinity could have been taken
In addition, other factors such as discharge,
precipitation, and a numerical instead of a
categorical approach to flow rate could be done
Acknowledgements
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National Science Foundation
Sevilleta LTER
2009 REUs and Interns
Jennifer Johnson
Ayesha Burdett
Ben Specter
Cathy McQueen
UNM Department of Biology
US Fish and Wildlife
References
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Carter, J.L., Resh, V.H., Hannaford, M.J., and Myers, M.J. 2006.
Macroinvertebrates as Biotic Indicators of Environmental Quality.
Pages 805-833 in F. R. Hauer and G. A. Lamberti (Eds.) Methods
in Stream Ecology. Elsevier Science & Technology Books.
Merritt, R.W. and Cummins, K.W (eds.). 1984. An Introduction to
the Aquatic Insects of North America, 2nd ed. Kendall/Hunt
Publishing Company, Dubuque, IA.
Peckarsky, B.L., Fraissinet, P.R., Penton, M.A., and Conklin Jr.,
D.J (Eds.). 1990. Freshwater Macroinvertebrates of Northeast
North America. Cornell University Press, Itaca, NY.
Rosas, I., Mazari, M., Saavedra, J., Báez, A.P. 1985. Benthic
Organisms as Indicators of Water Quality In Lake Patzcuaro,
Mexico. Water, Air, and Soil Pollution 25: 401-414.
Smith, D.G. 2001. Pennak’s Freshwater Invertebrates of the
United States: Porifera to Crustacea. Jon Wiley & Sons, Inc., New
York, NY.
Questions?