River+Ecology+Lab+Student+Manual

River Ecology Lab

**//Important Information://**

Come prepared and dressed for aquatic habitats - you may want to wear waders (provided) or waterproof boots if you go into the water to collect samples for the lab exercise. -To measure physical, chemical and biotic characteristics of the Red Cedar River -Learn how to use aquatic sampling gear and chemical kits -Learn to quantify and assess species diversity in natural environments The purpose of this laboratory is to explore the physical and biotic parts of the aquatic environment. We will do this by studying a section of the Red Cedar River. **Part I** of the exercise will deal with measuring physical parameters, such as flow rate, water chemistry, and temperature; **Part II** deals with the biotic parameters, such as types and numbers of species found in the rocks and sediments. **Part I: Physical and Chemical Aspects** We will attempt to characterize the river around the dam behind the Administration building. **Further tests that we will not be conducting, but that you might try for your group projects, can be found after the description of this lab’s activity.** Data collected can be compared to Tables 1 and 2. Record all data collected on the River Ecology Data Sheets provided at the end of this section. **A. __PHYSICAL ASPECTS__**
 * Objectives:**

The dimensions of a stream channel can affect flow rates and influence the types of habitats available for fish and invertebrates. A **riffle** is a section of a river that is characterized by fast flow and turbulent surface water such as at a small rapid. A **run** is a section of a river characterized by laminar or smooth flow of surface water.  We will be examining the flow characteristics of the river at the surface. It can also be done at different depths using a flow meter, but we will not be using one in this lab. 1) **F****low Rates at the Surface:** In this exercise, we will measure the surface flow rate 2 meters from the shoreline using a tennis ball. You will need to measure a distance of 6 meters between two transects/points across/along the river. A student will release a tennis ball above the upstream point. Students on shore will time the passage of the tennis ball from the upstream point to the downstream point. Record the data in the data sheet provided. A student down stream should retrieve the tennis ball using a dip net.  At the site, measure at least **3 times**:  1) **Air temperature** away from the water and the **Water Temperature** close to where flow measurements were taken. Temperature is not likely to vary according to depth at different positions across the river, but you may wish to show this by taking readings. Several measures of air temperature should be taken during the lab period to illustrate the less buffered temperature of terrestrial environments compared with that of the water. Record these data in the data sheet provided**.**

For this exercise, students will determine the levels of various chemicals that are vital to animals and plants in aquatic systems. Several lectures deal with the importance of certain chemicals and their role in aquatic ecosystems. The purpose of this exercise is to learn how to measure the levels of some of these chemicals. Comparison of these values to other rivers and to standard water values will provide a measure of the purity of the Red Cedar River. We will do selected analyses, as allowed by our sample kits and resources. Some chemical tests are just included for educational purposes, others we will be performing. **For chemical kit tests, follow the instructions provided in the kit.** Nitrogen is an abundant gas in the atmosphere. In its molecular form, N2, few organisms can use it. It must be converted to ammonia, nitrate or an organic form first to be used. The most common, and usable, form of nitrogen in most habitats is nitrate. Measuring nitrate in aquatic (and other) habitats involves converting nitrate to ammonia, and measuring ammonia. The amount of available nitrogen in the habitat is an important measure of the ability of organisms to produce biomass. Protein synthesis is dependent on nitrogen sources for most organisms. It is this biological process that humans attempt to stimulate by applying “fertilizer.” Fertilizers often have high concentrations of nitrogen in a form that is readily available to plants. Fertilizer in aquatic systems, usually present as the result of run off (pollution) from over-fertilized agricultural fields, also stimulates plant growth. Often this growth is viewed as highly undesirable since it affects the species diversity and health of the aquatic community. //Equipment and supplies// LaMotte kit for Ammonia testing LaMotte kit for Nitrate-N & Phosphate testing In aquatic systems, phosphorus is usually a limiting resource. That is, plant growth is restrained by lack of sufficient amounts of phosphorus. The common usable form of phosphorus is phosphate (PO4), which is relatively insoluble and has a very short residency time in the aquatic environment. It readily forms insoluble salts in the sediments with the remainder being tied up in plant biomass. Excesses of phosphate can cause algal blooms that may create other pollution problems. In lakes, natural eutrophication is accelerated by excess phosphate. //Equipment and supplies// LaMotte kit for Nitrate-N & Phosphate (Note: the kit tests for orthophosphate only) Oxygen is essential for most life in aquatic systems and as such is an important property of water to measure. It is measured as dissolved oxygen (**DO**) in parts per million (ppm). Oxygen is used for metabolic respiration and is also important to many chemical reactions that occur in water. The oxidation-reduction state of important chemicals like nitrate and ammonia, ferrous and ferric ions, sulfates and so on are influenced by the amount of **DO** is the water. Unlike in the atmosphere, dissolved oxygen in the water is highly variable and generally low in concentration. It is influenced by the water temperature (colder water contains more DO), salinity, photosynthesis and respiration. //Equipment and supplies// LaMotte kit for dissolved O2 The hydrogen ion concentration of water is very important to the growth of plants and animals, and their diversity and distribution. Hydrogen ions affect many chemical reactions that also affect plants and animals. The concentration of hydrogen ions [H+] is usually expressed as a log scale called the pH. pH = log (1/ [H+]) When concentrations of [H+] and OH- are equal, the pH of the solution is seven, or neutral. Values of pH less than seven show acid conditions and values greater than seven show basic conditions. Between pH of 6.0 and 7.5, relatively large amounts of acid or base are required to make small changes in the pH in water that is well buffered with bicarbonate ions. This range is the usual range for most ponds, lakes and streams found in nature. //Equipment and supplies// 2 Hach pH meters paper towels or LaMotte Kit for pH 4 small plastic beakers calibration solutions or pH paper squirt bottle of deionized water
 * B. __CHEMICAL ASPECTS__**
 * Procedures and Measures**
 * Nitrate and //*Ammonia//** (__only Nitrate will be performed in today’s laboratory activity__)
 * Phosphate**
 * Dissolved Oxygen**
 * pH**


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**Dissolved O2**: Daily average must be 5.0 mg/L (ppm) with no single values 4.0 or below. **Temperature, °C:** Maximum values must be below 28 °C. **Total dissolved solids:** Maximum must be below 750 mg/L (ppm). **pH:** Maximum 8.5, minimum 6.5, in standard units. **Ammonia as NH3:** No standard, but should be below 0.006 mg/L (ppm). **Ammonia as N:** No standard, but should be below 0.20 mg/L (ppm). **Nitrate and Nitrite as N:** No standard, but should be below 0.5 mg/L (ppm) //Note: Compare total dissolved solids (TDS) to our measure of turbidity, but be aware that TDS does not account for suspended solids.//
 * Table 1: Michigan water quality standards for streams and rivers.**

Water Temperature °C 19.0 Conductivity, µS/cm 486.0 Dissolved O2, ppm 9.8 pH 8.1 Alkalinity, CaCO3, ppm 186.0 Ammonia, ppm 0.024 Nitrate & Nitrite, ppm 0.4 Total Dissolved solids in ppm 322.0 Hardness, ppm 77.0 Phosphate, ppm 0.009 Silicate, ppm 4.90 Sulfate, ppm 29.0 //Data extracted from R. Woods and J Wygant. 1979. River Raisin study at Manchester. August 8 and September 11, 1979. MI DNR, Pub. 3730-0040// //No data were provided for suspended solids.//
 * Table 2: Comparative data from Raisin River in southern Michigan, Sept. 11, 1979 at 12:00 hours.**

**Part II: Diversity of aquatic organisms** A variety of organisms live in aquatic systems. In streams, such as the Red Cedar River, most organisms are attached to the rocks at the bottom, or live in the sediments. Only strong swimming, larger species such as fish and some larger aquatic insects live in the water column or at the surface. In this section, your TA will instruct you as to what procedures to perform in the lab exercise. At the site, collect bottom (benthos) samples by using: 1) **K****ick-screen Sampler** Sample near the shoreline and near the center of the river. Samples should be washed off the screen into a bucket on the shore. Animals should be placed into plastic bags for later examination in the lab (plastic bags are provided - fill the bags about ¼ full of river water). Label each bag with date, section, type of sample and position in the river. These samples are useful for qualitative sampling since the area sampled is not known.  2) **Surber Sampler** Sample at two locations in the main channel and in the slower flowing edges. This sampler is more **quantitative** than the kick-screen since a known area (measure and calculate the area of the metal frame) is sampled. Once the sampler is firmly in place on the bottom, the person who will be disturbing the benthos area in the sample frame should try to pick up the larger (hand sized) rocks and place them in a bucket. These rocks may have invertebrates and algae on them that can be examined later. Sometimes, the water in the river is too deep for the top of the net to be out of the water, so some animals may escape. Thus, the Surber sampler works best in shallower water. 3) **Hess Sampler** Sample at two locations in the main channel. This sampler may not work at all in slower flowing waters. This sampler is also **quantitative** since a known area is sampled. Be sure to measure the sampler radius and calculate the sampled area (**Area**= πr**2**).  4) To collect organisms that may be drifting in the current, **dip nets** and **tow nets** may be used. The samples collected by all these techniques should be brought to shore where the collected specimens can be transferred to the labeled plastic bags. Use a squirt bottle to aid in washing specimens into the bag. Make sure a careful record is made of the sample and location in the river for all specimens. Examine the samples and identify and count the various organisms. Diagrams of the most likely orders of animals are available for this. Where an animal cannot be matched to any diagram, or many different species of the same type of animal are present, make up species categories. For example, if a small beetle is found in some numbers, and a large one of a different color, give them categories as “small beetle,” “larger beetle” in the data form. We will construct a species diversity index. Identifying and counting the organisms may take more time than available in the lab. For this reason, we will spend some time identifying and counting the organisms, but use the data provided in Tables 7 and 12 for further comparisons and analysis. For any of the sampling procedures described above that require disturbing the river benthos area, **1 or 2 minutes** of kicking in front of the net/sampler is considered sufficient to acquire a good sample. Once we have collected a variety of aquatic organisms, we will take them back to the lab for a closer look. In this exercise we will try to group insects into like forms and look at diversity. If time allows, we will take yet a closer look at our specimen and place them into groups based on their niche in aquatic systems. We may have a chance to apply the following section to our samples. Data will be recorded on the **Biotic Data Sheet**.
 * Sampling Procedures and Devices**

BIOTIC CHARACTERISTICS
Researchers studying the species diversity of communities often provide //indices// of species diversity. These indices are useful in comparing a variety of communities, and they can be important tools to detect pollution or other environmental degradation. Aquatic invertebrates are often used as indicators of water quality, and have been used in developing an index of biotic integrity (IBI). The presence of certain species known to be either pollution tolerant or sensitive is a valuable indicator of the health of aquatic ecosystems. The **Shannon index** may be used for data that represent a random sample of species from a larger community, a criterion that our data meet. The index can be calculated on the relative abundance or coverage of species in the community. We will use the //relative abundance// of species in the sampled habitats. **//Species Diversity,//** //H’ = -Σ[ pi * log10pi ]// (1) where **//pi//** is the //relative abundance// of species //i//. The value of **//H//** is obtained by summing each species relative abundance value multiplied by the log base 10 of its relative abundance value. This equation written in standard calculator notation would be **//H//** =-1* ((**//pi//** * (log10 **//pi//** ))). For example, if the relative abundance of species 1, 2 and 3 is: **//p1//**= 0.67, **//p2//** =0.24 and **//p3//**= 0.09, respectively, then the calculation would be done as follows: **//H//** =- [(0.67 x log10 0.67) + (0.24 x log10 0.24) + (0.09 x log10 0.09)]= - [0.67 x -0.174 + 0.24 x -0.620 + 0.09 x -1.046] = - [-0.117 - 0.149 - 0.094] = 0.36. As can be seen from the example, a single value for **//H//** is obtained for the sample, using all species present. **//H’// values range from a minimum value of 0 (only one species in the community) to a maximum value: log(1/# of species categories in the community). Larger values of //H’// indicate greater species diversity in the community.** 1. The number of species, termed //species richness, **s**,// and 2. The relative abundance of species, termed //evenness, **J**//. If we sampled two habitats, what does it mean if **//H’//** is greater for one habitat than the other? We can compare the two habitats directly for species richness. The habitat with more species is considered more diverse. Species evenness refers to the distribution of abundance among the species present. For example, evenness is greater for a set of 10 species all of which have about the same abundance than for 10 species where one species is very abundant and the others very rare. Evenness is expressed as the ratio of the observed diversity to the maximum diversity given equal abundance of each species. Given equal species richness in several habitats, the one with the highest evenness is considered to be more diverse. //Species Richness, s = number of species in habitat// //Maximum Diversity, H’max = log10s// (2) Evenness, **//J//**, is then calculated as: //Evenness, J’ = H’/H’max// (3) Evenness will vary from near zero when most individuals belong to one species, to 1.0, when each species is equally abundant.
 * //H’//** combines two aspects of species diversity:

This section provides some sample data collected at the Red Cedar River.
 * SAMPLE DATA**

**Table 3:** Width and depth of the Red Cedar River at a //riffle.// A riffle is a section of a river that is characterized by fast flow and turbulent surface water such as at a small rapid.
 * **Width** || **Depth (m)** ||
 * 0 || 0 ||
 * 1 || 0 ||
 * 3 || 0.14 ||
 * 6 || 0.25 ||
 * 9 || 0.32 ||
 * 12 || 0.34 ||
 * 15 || 0.2 ||
 * 18 || 0.1 ||
 * 21 || 0 ||
 * 24 || 0.05 ||
 * 25 || 0 ||

**Table 4:** Flow rates in the riffle habitat calculated from a surface float
 * **Width position (m)** || **Distance moved (m)** || **Time (sec)** || **Flow Rate (m/sec)** ||
 * 5 || 10 || 20 || 0.5 ||
 * 8 || 10 || 28 || 0.36 ||
 * 11 || 10 || 15 || 0.67 ||
 * 14 || 10 || 18 || 0.56 ||
 * 17 || 10 || 15 || 0.67 ||
 * 20 || 10 || 16 || 0.63 ||

**Table 5:** Flow rates in the riffle habitat measured with the pygmy flow meter Position across river (m)
 * Depth || 3 || 6 || 9 || 12 || 15 || 18 || 21 || 24 ||
 * Top || 0.55 || 0.67 || 0.69 || 0.72 || 0.66 || 0.52 || 0 || 0.44 ||
 * Middle || 0.43 || 0.60 || 0.62 || 0.67 || 0.59 || 0.44 || 0 || 0.31 ||
 * Bottom || 0.32 || 0.48 || 0.51 || 0.55 || 0.47 || 0.31 || 0 || 0.18 ||

**Table 6:** Red Cedar River Riffle Chemical Characteristics || **SUSPENDED SOLIDS or TURBIDITY** (Note: ppm=mg/L)

**(SALINITY)** ||  |||||| Reading (µS/cm or mS/cm) ||   ||
 * |||||| Reading (mg/Liter) ||  ||
 * || Sample # || 1 || 2 || 3 || mean ||
 * || 1 || 32 || 30 || 29 || 30.33 ||
 * || 2 || 32 || 31 || 29 || 30.67 ||
 * || 3 || 34 || 31 || 29 || 31.33 ||
 * **CONDUCTIVITY**
 * || Sample # || 1 || 2 || 3 || mean ||
 * || 1 || 0.88 || 0.88 || 0.88 || 0.88 ||
 * || 2 || 0.87 || 0.87 || 0.87 || 0.87 ||
 * || 3 || 0.87 || 0.86 || 0.87 || 0.867 ||
 * **pH** ||  |||||| Reading (log (1/[H+]) ||   ||
 * || Sample # || 1 || 2 || 3 || mean ||
 * || 1 ||  ||   ||   || 8 ||
 * || 2 ||  ||   ||   ||   ||
 * || 3 ||  ||   ||   ||   ||
 * **ALKALINITY** |||||||||| Reading (ppm CaCO3)= 0 ||
 * **AMMONIA** |||||||||| Reading (ppm NH3)= 1 ||
 * **CO2** |||||||||| Reading (ppm CaCO3)= 7 ||
 * **DISSOLVED OXYGEN** |||||||||| Reading (ppm O2)= 4 ||
 * **HARDNESS** |||||||||| Reading (ppm CaCO3)= 400 ||
 * **NITRATE-N** |||||||||| Reading (ppm NO3)= <0.2 ||
 * **PHOSPHATE** |||||||||| Reading (ppm PO4)= <0.2 ||
 * **SILICA** |||||||||| Reading (ppm SiO2)= 6 ||
 * **SULFIDE** |||||||||| Reading (ppm S)= 0.1 ||

**Table 7: Riffle Biota** (area sampled = 100 cm2) A riffle is a section of a river that is characterized by fast flow and turbulent surface water such as at a small rapid. Functional groups describe the habitats and ecology of the different species of aquatic invertebrates. Filterers collect drifting particles of different sizes that can include suspended solids, sloughed off algae, small animals, etc. Scrapers scrape biofilm off rocks, and derive nutrients from the algae, bacteria, and fungi in the biofilm. Shredders tear up dead plant material and are therefore detritivorous. Much of the energy in stream communities originates in the riparian zone…depending on stream size, up to 90%. Total species richness (s) for the riffle habitat = 15 (pi) || H’ = 0.79
 * Order || Family || Genus || Species || Functional Group || Abundance || pi || log(pi) || pi*log
 * Diptera || Simulidae || Simulium || prospectus || Filterer || 35 || 0.07 || -1.18 || -0.08 ||
 * || Chironomidae || Chironomus || benthota || Gathering || 248 || 0.47 || -0.33 || -0.15 ||
 * || Tipulidae || Hexatoma || enclosus || Shredder || 5 || 0.01 || -2.02 || -0.02 ||
 * Coleoptera || Dytiscidae || Hydroporous || magna || Predator || 2 || <0.01 || -2.42 || -0.01 ||
 * || Elmidae || Stenelmus || lithophilus || Gathering || 25 || 0.05 || -1.32 || -0.06 ||
 * Megaloptera || Sialidae || Sialis || modela || Predator || 2 || <0.01 || -2.42 || -0.01 ||
 * || Corydalidae || Nigronia || perca || Predator || 1 || <0.01 || -2.72 || -0.01 ||
 * Ephemeroptera || Baetidae || Baetis || limbata || Scraper || 25 || 0.05 || -1.32 || -0.06 ||
 * || Heptageniidae || Stenonema || perssona || Scraper || 43 || 0.08 || -1.09 || -0.09 ||
 * || Ephemeridae || Hexagenia || limbata || Filterer || 0 || 0 || 0 || 0 ||
 * Trichoptera || Helicopsychidae || Helicopsyche || helica || Scraper || 36 || 0.07 || -1.16 || -0.08 ||
 * || Hydropsychidae || Hydropsyche || fluviatilis || Filterer || 74 || 0.14 || -0.85 || -0.12 ||
 * || Polycentropodidae || Polycentropus || foragus || Filterer || 12 || 0.02 || -1.64 || -0.04 ||
 * || Limnelphilidae || Platycentropus || macrochirus || Filterer || 10 || 0.02 || -1.72 || -0.03 ||
 * Plecoptera || Perlidae || Isoperla || nigronia || Predators || 3 || 0.01 || -2.24 || -0.01 ||
 * || Peltoperlidae || Peltoperla || exsectoides || Shredder || 4 || 0.01 || -2.12 || -0.02 ||

Ball, R.C. and T.G.Bahr. 1975. Intensive survey: Red Cedar River, Michigan. //In// River Ecology. B.A. Whitton (Ed.), Blackwell Science Publications, Oxford. Pp 431-460. (Chapter 17) Cummins, K.W. 1975. Macroinvertebrates. //In// River Ecology. B.A. Whitton (Ed.), Blackwell Science Publications, Oxford. Pp 181-198. Wilhm, J.L. and T.C. Dorris. 1968. Biological Parameters for Water Quality Criteria. Bioscience 18:477-481.
 * Selected References**

For today’s lab, we are sampling physical, chemical and biotic aspects of the Red Cedar River. //Field Collections//: Our sampling location is behind the Administration Building, just below the low head dam. While at the river, each group needs to take the following: Once each group has finished collecting samples, return back to the classroom for sample analyses. Each group will be split into two, and one half will be in charge of chemical tests, while the other looks at the aquatic macroinvertebrates. //Macroinvertebrate Analysis//: Take the sample and run it through a sieve to remove most of the water out of the sample. Transfer the contents from the sieve into a pie tin using a small amount of water. Use the pipettes and forceps to find different individuals. Identify the invertebrates to functional feeding groups based on their niches (filtering collectors, gathering collectors, scrapers, shredders or predators). Record your data on Data Table 4. //Water Chemistry Analyses//: Students will determine pH, Nitrate-Nitrogen, Phosphate, and Dissolved Oxygen. In order to save time, each group will only perform either pH (kit and pH paper) and Dissolved Oxygen or Nitrate-Nitrogen and Phosphate. Directions for each test are found inside the test kit and need to be followed step by step. Record your data on Data Table 3. Please use goggles and gloves for safety and make sure to use test tube racks for all tubes. NOTE: The dissolved oxygen test kit is tricky, fill the water bottle in the kit and also make sure you fix the sample first, and then proceed on with the next steps. Share your data with the class. Calculate the Shannon Weiner Index of species diversity for the run biota on Data Table 4. How does this data compare to the riffle data in Table 7 earlier in this section? Why might there be differences? What can this show us about conditions in different habitats and niches? At the end of lab, each group needs to turn in all data tables and sheets (the 3 pages following this one). **Your evaluation for this lab will be based on your river and biotic data sheets, your H’ calculation and the comparison of run and riffle species diversity.**
 * ACTIVITY**
 * 1) A water sample using a nalgene bottle - Completely fill the bottle to the brim, and cap it off under the water. By allowing no excess oxygen in the sample, you will have much more accurate Dissolved Oxygen (DO) and other chemistry readings.
 * 2) Surface flow readings using a tennis ball, 30m tape and the stopwatch- Two students from each group stand 6m apart from each other in the middle of the river. The upstream student drops the ball and one of the students on shore measures the time it takes for the ball to reach the downstream student. It is easy to lose the tennis balls here, so the downstream student should have a D-net to help scoop up the tennis ball. Flow measurements need to be repeated 3 times. Record your data in Data Table 1.
 * 3) Three measurements of air and water temperatures- Record your data Data Table 2.
 * 4) Aquatic macroinvertebrate samples using one of the many collection methods- For any of these nets kick up the benthos or sediment for at least 1-2 min. Take the sample to the shore and transfer it into your bucket to take back to the lab. If you are unable to see any invertebrates in your sample, repeat the sampling methods. Record how many times you sampled.


 * RIVER ECOLOGY – DATA SHEETS**


 * Data Table 1:** Flow rates in the run habitat calculated from a surface float
 * **Distance moved (m)** || **Time (sec)** || **Flow Rate (m/sec)** ||


 * Data Table 2:** Air and water temperature
 * || **Reading 1** || **Reading 2** || **Reading 3** || **Mean Temp** ||
 * **Air Temp oC** ||  ||   ||   ||   ||
 * **Water Temp oC** ||  ||   ||   ||   ||


 * Data Table 3**: Class summary of the Red Cedar River run chemical characteristics
 * **Test** || **Reading 1** || **Reading 2** || **Reading 3** || **Mean** ||
 * Phosphate (ppm PO4) ||  ||   ||   ||   ||
 * Nitrate-N (ppm NO3) ||  ||   ||   ||   ||
 * Dissolved O2 (ppm O2) ||  ||   ||   ||   ||
 * pH (kit) (log (1/[H+]) ||  ||   ||   ||   ||
 * pH (paper) ||  ||   ||   ||   ||

** (pi) ** || ** pi*log ** ** (pi) ** || H’ =
 * Data Table 4: Run Biota** (area sampled = 100 cm2) This data sheet is included as an example. A run is a section of a river characterized by laminar or smooth flow of surface water. Much of the energy in stream communities originates in the riparian zone…depending on stream size, up to 90%. Total species richness (s) for the run habitat = 13
 * ** Order ** || ** Family ** || ** Genus ** || ** Species ** || ** Functional Group ** || ** Abundance ** || ** pi ** || ** log **
 * Diptera || Simulidae || Simulium || prospectus || Filterer || 0 ||  ||   ||   ||
 * || Chironomidae || Chironomus || benthota || Gathering || 580 ||  ||   ||   ||
 * || Tipulidae || Hexatoma || enclosus || Shredder || 25 ||  ||   ||   ||
 * Coleoptera || Dytiscidae || Hydroporous || magna || Predator || 14 ||  ||   ||   ||
 * || Elmidae || Stenelmus || lithophilus || Gathering || 8 ||  ||   ||   ||
 * Megaloptera || Sialidae || Sialis || modela || Predator || 3 ||  ||   ||   ||
 * || Corydalidae || Nigronia || perca || Predator || 4 ||  ||   ||   ||
 * Ephemeroptera || Baetidae || Baetis || limbata || Scraper || 7 ||  ||   ||   ||
 * || Heptageniidae || Stenonema || perssona || Scraper || 4 ||  ||   ||   ||
 * || Ephemeridae || Hexagenia || limbata || Filterer || 34 ||  ||   ||   ||
 * Trichoptera || Helicopsychidae || Helicopsyche || helica || Scraper || 7 ||  ||   ||   ||
 * || Hydropsychidae || Hydropsyche || fluviatilis || Filterer || 0 ||  ||   ||   ||
 * || Polycentropodidae || Polycentropus || foragus || Filterer || 21 ||  ||   ||   ||
 * || Limnelphilidae || Platycentropus || macrochirus || Filterer || 15 ||  ||   ||   ||
 * Plecoptera || Perlidae || Isoperla || nigronia || Predators || 0 ||  ||   ||   ||
 * || Peltoperlidae || Peltoperla || exsectoides || Shredder || 15 ||  ||   ||   ||

BIOTIC STUDIES DATA SHEET

 * In the space below, record the number of species and the number of individuals of each species collected. If time allows, place each species into a group based on its niche** (filtering collectors, gathering collectors, scrapers, shredders or predators). Functional groups describe the habitats and ecology of the different species of aquatic invertebrates. Filtering and gathering collectors collect drifting particles of different sizes that can include suspended solids, sloughed off algae, small animals, etc. Scrapers scrape biofilm off rocks, and derive nutrients from the algae, bacteria, and fungi in the biofilm. Shredders tear up dead plant material and are therefore detritivorous. Predators eat other aquatic macroinvertebrates. **Include a tally of the total number of species in each group.**

** FURTHER RIVER TESTS WE WILL __NOT__ BE PERFORMING ** **//__ *River dimensional characteristics __//** // Typically, when studying a river, ecologists will determine the width and depth of the river. In our lab exercise today, we will **__not__** be doing this activity. Below, however, are directions on how to do so: // // 1) **Width of the river**, using the 30m measuring tapes. The tape should be stretched tautly across the river and should not touch the water. An average width must be estimated, since the shoreline is uneven. This tape should be left in place for use in measuring water flow rates. // // 2) **Depth of the river** at regular intervals across its width (say, every 3m). Measuring depth will require a second tape measure and a wooden pole, or a meter stick. If a tape and pole are used, the end of the tape is hooked to the end of the pole and the tape is held tightly along the pole's length. The pole is then pushed to the bottom and held vertically. The height of the water is then read from the tape. //

// A river cross-sectional profile can be constructed from these measurements. The cross-sectional area can be computed by dividing the profile into rectangles across the middle portion and triangles near the shore. //

// Turbidity is an optical property of water that causes light to be scattered or absorbed, causing the water to become less transparent. At least three variables affect turbidity: 1) suspended solids such as particles of clay or silt, 2) dissolved chemicals, such as tannins, acids and salts, and 3) microorganisms. The measure of turbidity is important, as it is an index of the ability of light to penetrate water and thereby drive photosynthesis in plants. // // One can make this measure using a portable spectrophotometer. Follow the procedure described below, as taken from pages 161 & 162 of the Hach manual (in plastic protectors). If one does not have a blender, the sample can be strained through a fine screen. After a sample has been strained, the calibration procedure should be done using tap water; then one can measure the suspended solids in the sample. The sample should be swirled just before placing it in the reading chamber to re-suspend any larger particles. Several readings should be taken from the main sample (pour out the sample just read and pour in additional sample water). Several main samples may be taken and read if time allows. A mean can be calculated from all the readings taken. **(NOTE: the glass cells are very soft and can be scratched easily. Wipe them using only the cotton cloth provided. Students should handle the cells by the lip to avoid getting fingerprints on the lower parts.)** After the procedure is done, rinse the sample cells with tap water, dry with the cotton cloth and place them in the protective box. Note: we are unable to measure turbidity in the ecology lab. //
 * // *Turbidity //**

// Conductivity is the reverse of electrical resistance. It is a measure of the amount of ions in the water, and as such, is an indirect measure of salinity. Salinity directly affects the osmotic concentration of solutes, an important physical property of water for all aquatic life. Water and salt balances in the bodies of organisms living in water are directly affected by the salinity. Polluted water often has higher salinity. Therefore, salinity measurements are useful in assessing how much pollution is in a system. Water with higher conductivity will also have higher salinity. The procedure can be seen on pages 43 & 44 of the Hach manual (in plastic protectors). The procedure involves collecting a sample, turning on the meter, setting the range to the highest range and reading the sample. Take several samples and readings of each. The probe should be rinsed thoroughly with deionized water after each reading. NOTE: the readings are in µS/cm or mS/cm. S refers to Siemen, a unit of conductivity, related to resistance as the reciprocal of an ohm. **Note: we are unable to measure conductivity and salinity in the Ecology Lab.** //
 * // *Conductivity & Salinity //**

// Alkalinity, the capacity to neutralize strong acids, depends on the concentrations of buffers and bases in the water. In most waters, the dominant buffering system is the carbonate-bicarbonate system. Measuring alkalinity is important because of the major importance of dissolved carbon dioxide (CO2) in aquatic systems. Carbon dioxide is present in three main forms: CO2, HCO3 (bicarbonate) and CO3= (carbonate). Alkalinity is often expressed as an equivalent in parts per million (ppm) of CaCO3 because the calcium ion is a major associate of carbonate and bicarbonate in fresh waters. Calcium ions, however, are not the major determinant of alkalinity. Alkalinity is also determined by carbonate, bicarbonate and hydroxide ions. The relative concentration of these ions also determines the pH of the water, an important property for nearly all creatures living in the water. // // Equipment and supplies // // LaMotte kit for testing Alkalinity // // LaMotte kit for CO2 //
 * // *Alkalinity and Carbon dioxide //**

// *Sulfate //
// This is a common anion in water and soil. It is measured as SO4-2, sulfate or as S-, sulfide. Sulfate is a common pollutant produced by mining, paper pulp and combustion of fossil fuels. In high concentrations, it can damage aquatic and terrestrial ecosystems primarily by producing acid rain. //

// Equipment and supplies // // LaMotte kit for Sulfide. (Note: the kit measures sulfide, S-) //

// Silicon dioxide, SiO2, commonly called silica, is present in nearly pure form in quartz rocks that make up much of the earth’s crust. In water, dissolved silica is important for the production of tests (shells) of diatoms and other algae. The populations of some species of diatoms may be regulated by the silica in the water (see Lund 1950). // // Equipment and supplies // // LaMotte kit for Silica //
 * // *Silica //**

// Hardness is a measure of the concentration of primarily calcium and magnesium in the water. These chemicals are important in setting the pH and the solubility of phosphate and carbonate (see alkalinity above, pH below). In water, the concentrations of these minerals determine the precipitation of soap, what we consider the “hardness” of the water. Other properties of these metal ions deal with their ability to reduce the toxicity of some chemicals. // // Equipment and supplies // // LaMotte kit for Hardness //
 * // *Hardness //**

// * **Leaf Packs** // // Leaf packs can be used to collect shredders and collectors (different aquatic insects). Leaf packs provide both a food source and shelter for these insects and are thus, colonized. In addition, predatory insects may also be detected. (Leaf packs have many uses in aquatic ecology…ask your TA if you would like to know more.) Be careful not to lose any insects when you remove the leaf pack…it may be helpful to have a net handy. //