Module 10/11 Stream Surveys Stream Surveys – February 2004 Part 4 – Biological Assessment

Module 10/11Stream Surveys

Stream Surveys – February 2004Part 4 – Biological Assessment

Developed by: Richards, Reed, Ruzycki Updated: February 2004 U3-m10/11d-s2

Objectives

Students will be able to: explain the role of periphyton in determining

environmental conditions. describe methods used to analyze periphyton samples. explain why macroinvertebrates are used as indicators

for water quality. describe methods used to collect benthic

macroinvertebrates. explain how fish can be used to determine water

quality. categorize and provide examples of common fish types

found in streams. use the index of biological integrity to characterize fish

communities in streams and lakes.


Stream assessments

Water quality Habitat Hydrologic Biological Watershed


Biological assessments


Biological assessments

Aquatic vegetation: periphyton macrophytes

Macroinvertebrate sampling Fish


Stream organism diversity

Just a general view of diversity – in Northern Minnesota there may be roughly 40 species of fish, 400-500 species of macroinvertebrates, and maybe 4000 species of algae.


Periphyton


Periphyton as indicators

Periphyton are used as indicators of environmental condition because they respond rapidly and are sensitive to a number of anthropogenic disturbances, including: habitat degradation nutrient enrichment metals herbicides hydrocarbons acidification


Periphyton Biomass Measurements

Ash-Free Dry Weight

Pigment Analysis

Biovolume Measurement


Periphyton – Sampling methods

One way to scrape a known area is to lay a plastic 35 mm slide (film removed) over the rock and scrape off the material within the slide area

scrub area = 2.3cmX3.5cm=8cm2


Rocks don’t always look like they have much on them

Nearly all the stuff scrubbed off this one was organic matter –most of it living algaeS.Loeb and J.Reuter images

Periphyton – Sampling methods


Material from a rock scrub contains macro and micro invertebrates, detritus, fungi, bacteria, as well as algae

Periphyton – in situ sampling


Periphyton – III. Preservation methods

Lugols’s iodine can used if the algae of interest are soft bodied forms (i.e. blue-greens and green algae).

If interested only in diatoms, it may be best to preserve in 70% ethanol.

Freeze sediment samples if they are to be analyzed for surficial chlorophyll.


Here’s a portion of the previous sample after being deposited on a glass fiber filter in preparation for chlorophyll extraction or AFDW determination.

Periphyton – sample prep


Periphyton – pigment analysis

Chlorophyll extraction: Tear filter into several pieces Place in a test tube Add 10 mLs of 90% acetone Extract overnight at 4oC

Chlorophyll analysis After 18-24 hr extraction,

centrifuge to settle filter debris Read absorbance or fluorescence

of the supernatant


Periphyton – biomass estimation

• Wet weight

• Dry weight (dried at 103–105 oC)

• Ash free dry weight (AFDW)

• Loss on ignition (LOI)

• Combust at 475-550 oC

• Chlorophyll (extract as per phytoplankton)

• Particulate organic carbon and/or nitrogen (POC or PON)

Muffle furnace


Project NameWater Quality Samples scrub area = 2.3cmX3.5cm=8cm2

2002 8 cm2=0.0008 m2 X 3 scrubs = .0024 m2 total areaNRRI Central Analytical Labemr 12/4/02

Sample Run chlorophyll phaeophytin volume total chlorophyllPeriphyton Date Date ug/L ug/L filtered (mLs) volume (mLs) mg/m2Whatever Creek 5/6/2002 5/15/2002 130 60 45 45 2.4

Sample Run Dry Wt AFDW total volume AFDWDate Date mg/L mg/L volume (mLs) filtered (mLs) g/m2

Whatever Creek 5/6/2002 5/8/2002 156 117 319 122 6.0

chlorophyll

AFDW

Once you have a measure of chlorophyll or AFDW you’ll need to calculate per unit area.

Periphyton – biomass calculations


Aquatic macrophytes

Macrophytes can provide habitat in streams

Bioassessment usually includes List of species present An estimate of percent

cover


Collecting benthic macroinvertebrates


Aquatic macroinvertebrates as indicators

Play important functional roles in stream ecosystems

Represent a fundamental link in the food web between organic matter resources (e.g., leaf litter, periphyton, detritus) and fishes.

Within specific biogeographical regions, assemblages respond in predictable ways to changes in stream environmental variables.

Because many have limited migration patterns or a sessile mode of life, they are particularly well suited for assessing site-specific effects.


Benthic Macroinvertebrates

Riverwatch protocol Collection Devices

D-nets Drift nets Sweep nets


Macroinvertebrate sampling protocol

1. Locate a safe sampling site within a riffle in a wadable stream.

2. Using a kick net, disturb the substrate in the area upstream of the net for about 2 minutes.

3. Use arm's length as a guideline for area upstream of net to disturb. Empty sample ( a "kick") into a bucket. Repeat until 3 kicks are collected, each from a different location in the riffle.



4. Samples should all be pooled in the bucket (a "replicate"). Add enough water to fill the bucket about half full.

5. Thoroughly mix contents of bucket to suspend organisms in the water column. Quickly scoop a sample using a subsampler. Transfer this subsample to a white picking tray.



6. Add water to ice cube tray compartments. Separate similar critters from the white picking tray into ice cube compartments using taxonomic resources as ID references. Sort all organisms in your white picking tray, not just those that are obvious.

7. Continue to subsample the bucket (mix well each time) until at least 100 organisms have been counted (if you like, you're welcome to count more!)



8. If about 100 critters have been counted before emptying the bucket, examine the "leftovers" for any obvious organisms that escaped sampling, especially those that are not already represented in your count. Include these in the final count.

9. Sample additional locations in the riffle if more organisms are needed (collect additional "replicates").

10.Count and record the number of individuals from each taxonomic group.


Sampling devices - nets

Kick-netD-net

Surber samplerdrift-net


Dredges Commonly used to grab a bottom sediment sample

in lakes, estuaries and slower moving rivers Collect soft sediments (mud and muck) for sieving

out benthic organisms and also obtaining bulk sediment characteristics

Common types Ekman Peterson Ponar Quantitative corers Box corers

Sampling devices - dredges


Benthic invertebrates – sample processing

Separating organisms from organic matter and sediments

Sorting into taxonomic groups

Identifying to desired taxonomic level

Data entry


Benthic invertebrates – sample processing

Rinse the sample in a 500 m mesh sieve to remove and fine sediment.

Sticks and leaves can be visually inspected and then discarded.


Benthic invertebrates - Sub sampling

Spread the sample evenly across a pan marked with grids

Randomly select 4 squares, remove the material preserve in jars


Benthic invertebrates - identification

Most organisms are identified to the lowest possible taxonomic level

Lowest taxonomic level depends on the goals of the analysis, expertise, and available funds


Benthic invertebrates – data processing

Metric An attribute with empirical change in value along

a gradient of human influence In other words, a measurement made to

determine if humans have had an impact in a natural system.

Index An integrative expression of site conditions

across multiple metrics. An index of biological integrity is often composed of at least 7 metrics. (Karr and Chu 1997)


Benthic invertebrates - data metrics

Many metrics have been developed for aquatic invertebrates.

Richness measures

Composition measures Tolerance measures

Trophic/habitat measures


Major groups of macroinvertebrates

Orders • Coleoptera-the beetles • The Crustaceans and Arachnida • Diptera-the true flies • Ephemeroptera-the mayflies • Hemiptera-the true bugs • Megaloptera-dobsonflies, alderflies, and fishflies • Odonata-dragonflies and damselflies • Plecoptera-the stoneflies • Trichoptera-the caddisflies • The worms


Macroinvertebrate keys

New York Dept Environmental Conservation http://www.dec.state.ny.us/website/dow/stream/orderpageone.htm

US EPA http://www.epa.gov/bioindicators/html/benthosclean.html

Save our Stream http://wsrv.clas.virginia.edu/%7Esos-iwla/Stream-Study/Key/MacroK

eyIntro.HTML Digital key to the aquatic insects of North

Dakota http://www.waterbugkey.vcsu.edu/Keyp1.htm

Duluth Streams http://www.duluthstreams.org/understanding/benthos_ID.html


Fish


Fish

Fish and other aquatic vertebrates can indicate stream quality

Extensive life history information is available for many species,

Because many fish are high order consumers, they often reflect the responses of the entire trophic structure to environmental stress

Fish provide a more publicly understandable indicator of environmental degradation

Fish generally have long life histories and integrate pollution effects over longer time periods and large spatial scales


Fish

Varieties Collection Methods

Seines Electroshocking

BackpackBarge or boat


Electroshocking

USFWS

http://www.epa.gov/nerlesd1/land-sci/water/fig9.htm


Netting

Seines

Slide to be completed by 3/31/04


Major groups of fish

Petromyzontidae - lampreys Acipenseridae – sturgeons Amiidae – bowfin Cyprinidae – minnows, dace, chubs, carp Catostomidae – suckers Ictaluridae – bullheads, catfish, madtoms Esocidae – pike Umbridae – mudminnows Umbridae – salmon, trout, whitefish Gasterosteidae – sticklebacks Cottidae – sculpins Moronidae – white perch, white bass Centrarchidae – bass, sunfish Centrarchidae – darters, perch, walleye


Fish – trophic designations

Piscivore Herbivore Omnivore Insectivore Filter feeder Generalist Invertivore


Fish: index of biotic integrity

http://www.epa.gov/nerlesd1/land-sci/water/fig3.htm



This index is a scientifically validated combination of measurements concerning fish communities in streams and rivers.

The components of a typical fish IBI fall into three broad categories: 1. fish species richness and abundance, 2. food chain composition and reproductive

function, and 3. fish abundance and condition.



An IBI is expressed as a single index value, based on the measurements of particular characteristics of the stream or river

Because the rivers and streams are physically, chemically and biologically diverse, the measured characteristics are compared to specific reference values for the type and location of river or stream.



IBI values range from 0 to 100. A low IBI value indicates the fish community is

substantially different from a minimally disturbed stream in the same geographic area.

A high IBI value indicates the fish community is similar to a minimally disturbed stream in the same geographic region


Stream surveys - references

Techniques of Water-Resources Investigations Reports http://water.usgs.gov/pubs/twri/

National Field Manual for the Collection of Water-Quality Data http://water.usgs.gov/owq/FieldManual/

Rapid bioassessment protocols for wadeable streams http://www.epa.gov/owow/monitoring/rbp/

Documents

Module 10/11 Stream Surveys Stream Surveys – February 2004 Part 4 – Biological Assessment