FISH 415 LIMNOLOGY UI Moscow

Transcription

1 FISH 415 LIMNOLOGY UI Moscow Sampling Equipment Purpose: - to familiarize you with limnological sampling equipment - to use some of the equipment to obtain profiles of temperature, dissolved oxygen, conductivity and light. - to produce limnological figures of the profiles. PART I EQUIPMENT Attached are drawings and pictures of standard limnological sampling equipment. You will be responsible for knowing the name and use of each. Be sure you understand the proper use of each as well as the operation of trigger mechanisms. If not, be sure to ask. PART II SAMPLING We will use the equipment to obtain data from Spring Valley Reservoir. Record all of your observations and make sure a copy is turned in to the T.A. for posting. Your data will be available via an excel spreadsheet on the course web page after the lab. (See attached sheet for complete instructions). ASSIGNMENT 1 Analysis of Profiles Purpose: - to analyze collected profile data and produce limnological figures - learn use of spreadsheets - perform simple statistics, regression analysis to calculate extinction coefficients. Data you will use are those you collected from the profiles. The data are available from the course website ( Labs and field trip tab. Computer spreadsheet You should be able to complete this lab on any computer running Microsoft Excel. (Note these instructions assume you are running Microsoft new installations on university computers and macs will differ slightly - you should be savy enough to figure out the differences. Given the university software agreement with Microsoft you can obtain the latest version at no charge, use it. Be sure you are comfortable with how to maneuver around in the spreadsheet, graph the data, combine plots on one page, and the proper anatomy of a scientific figure. You will be expected to hand in your figures in proper format. There are computer labs available for your use across campus - check the IT website for info and hours. See the course web page for info on spreadsheet primers. Tasks: 1) Plot profiles of temperature, dissolved oxygen (mg/l only), conductivity, ph and light for Spring Valley Reservoir. Place the data on separate graphs on one page (i.e., one plot

2 for all temperature profiles, one for all oxygen etc. Each profile on each graph should be easy to distinguish (use different symbols and line types - do not use color). Make sure each figure has a proper caption that indicates what the figure is about. (The idea here is that if the figure fell out of your notebook and someone picked it up they could interpret it). Write a short paragraph to summarize major trends in the data for each figure. This should be similar to the results section of a published manuscript - check the results section of the primary literature (journals e.g., L&O) for examples. 2) For the light profiles calculate the extinction coefficient. Do the calculations in two ways: i) calculate the extinction coefficient for each interval for each profile and then calculate the average for each profile; and ii) perform a regression analysis using depth as the independent variable and ln (natural log) irradiance as the dependent variable. The slope of this relationship will be the extinction coefficient (ignore the negative). (For regression, you will need to have the MS Analysis Tool pack installed on your computer - Excel typically does not install this automatically during a normal install - see the help menu on how to install on your machine. Don t forget that you want to use ln (natural log) of irradiance as the dependent (Y) variable. Prepare a proper table listing your calculated extinction coefficient(s). Calculate the depth at which 1% of the surface irradiance remains for each profile. How does this compare to 2*z? sd Figure 1A. Plot of temperature versus depth for Campus Lake on August 22, 2003, Jackson Co. Illinois, USA. Note: I expect figures to be in the proper limnological format, and properly labeled. Check a common journal to ensure you have all the necessary information on each figure. Your narratives should be grammatically correct and free of spelling errors. You don t have to put the figure caption below each figure, instead you can hand in a page of figure captions listing the figure number and corresponding caption.

3 Grading Criteria for assignment Figures (Each) 5 - figures complete including caption (labeled axes, units, lines and symbols different for different sites or times, all details present, no color). For profiles, Depth on y axis, increasing from top to bottom, variable measured on x axis at top of graph. 4 - figure caption missing or incomplete, use of color 3 - figure caption missing or incomplete, symbols and lines do not clearly distinguish sites or times. 2 - figure caption missing or incomplete, symbols and lines do not clearly distinguish sites or times, axes not labeled or units missing. 1 - figure caption missing or incomplete, symbols and lines do not clearly distinguish sites or times, axes not labeled or units missing, variables on wrong axes. Narrative (Each) 3 - complete paragraph, including topic sentence, highlights major trends seen in accompanying figure in writing. Includes range of numbers allowing reader to quantitatively reconstruct figure. 2 - paragraph structure incomplete, missing highlight of major trends or fails to include overview of main numbers from figure. 1 - paragraph not complete, does not include major trends in accompanying figure and does not include main numbers from figure. Extinction 5 - correctly calculated for all profiles, complete table coefficient 4 - Not all extinction coefficients correct, complete table 3 - incorrect coefficients, tables incomplete 2 - some calculations 1 - no extinction coefficients calculated

4 Spring Valley Reservoir Field Trip FISH 415 LIMNOLOGY UI Moscow Meet at 14:30 sharp in CNR 209. Remember to wear closed toes shoes and bring a pencil - Rain gear if needed. Unless it s storming, we plan to go - remember it will be cooler out on the water than on land - therefore rather overdress / plan for sunscreen etc. The purpose of this field lab will be to familiarize you with- and use standardar limnological sampling equipment and to characterize the pelagic zooplankton community and chemical environment in Spring Valley Reservoir. We will also compare the efficiency of different nets and traps at capturing zooplankton. Take profiles of temperature, oxygen, conductivity at 1 m increments and light at 0.5 m increments from the lake surface to the bottom (or end of photic zone 1% of surface irradiance). Make sure you record all of the data clearly and give a copy of your notes to the T.A. before you leave for the night. Take 1 L Chl samples (triplicates) from ½ way between the surface and the thermocline, and ½ way between the thermocline and the lake bottom. As well take an intergrated sample from the surface to the end of the photic zone (2* secchi depth). Other samples will depend on the depth of the thermocline. We want to see the influence of the various chemical and physical parameters on the zooplankton distribution. Realize some of the depths and samples below may need to be adjusted accordingly. Obtain triplicate TP samples from just below the surface, and every 2 to 3 m thereafter. Ideally we want to sample just above and below the thermocline. Make sure you don t hit the bottom with the water bottle or you will contaminate the entire site. Use the Kemmerer sampler to get water for TP, or team up with the group doing the profiles and obtain water from their sampler when they get to the required depths. To sample zooplankton, use the Schindler trap to take triplicate samples from just below the lake surface, and just above and below the thermocline. Evenly space two more sampling intervals (each with triplicate samples) between the bottom of the thermocline and the lake bottom. Use the closing plankton net to obtain 3 integrated plankton samples from the hypolimnion and the epilimnion. After each haul, empty the net contents into a sample jar and rinse the cod end. Clearly label the jar with date, collection time, site, depth, net size (mouth diameter) and haul length. Use a Wisconsin-style plankton net to obtain triplicate zooplankton samples from the entire water column - preserve each in it s own vial and label clearly with date, time, site, depth, net size and haul length. We may collect other samples depending on weather conditions (Langmuir circulations etc.) and time. Use the Ekman grab to collect 3 samples from the deep site. We ll use the K-B corer to take some cores as well. Be sure to label all bottles with the date, haul distance and gear used. Use extra tape if necessary. Use pencil on the P-tubes so we can read it after autoclaving.

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