ENV 220 Creating Graphs Template

ENV 220 Creating Graphs Template Overview For this assignment, you will generate two graphs (a scatter plot and a line graph). Scientists use several tools for statistical analysis of environmental data, including R, Python, Microsoft Excel, and more. In this course, you will be using Microsoft Excel as the tool for graphing and analyzing environmental data. You will also answer questions related to each graph that you create. These assignments are part of critically analyzing data and data-collection techniques for integrity and quality. You will perform your own data analysis when completing your final project. Activity One You work for the South Dakota Game and Fish Department. You and your colleagues were tasked with determining the mule deer fawn recruitment rate—the percentage of fawns to does that survive through the fall and are, therefore, successfully recruited into the deer population. The data you have collected are in Table 1 below. Enter the data below into an Excel spreadsheet. Then create a graph representing the data and answer the questions below. Population Size (Thousands of Deer) Mule Deer Fawn Recruitment Rate (%) 10.798 .16 10.000 .18 12.000 .25 10.987 .26 10.800 .26 11.000 .27 9.200 .25 9.000 .26 10.000 .30 9.300 .34 8.800 .34 7.700 .36 6.900 .36 5.000 .35 4.800 .37 6.600 .44 3.300 .45 6.000 .48 6.900 .49 7.000 .43 Table 4.1: South Dakota Mule Deer Data 10.798, 10.000, 12.000, 10.987, 10.800, 11.000, 9.200, 9.000, 10.000, 9.300, 8.800, 7.700, 6.900, 5.000, 4.800, 6.600, 3.300, 6.000, 6.900, 7.000 1

.16, .18, .25, .26, .26, .27, .25, .26, .30, .34, .34, .36, .36, .35, .37, .44, .45, .48, .49, .43 Graph Data Graph the data in an appropriate graphical format with a trendline through the data, the line equation, and the R-squared value (coefficient of determination) on the chart. Label Graph Label the graph, including all axes, a detailed title, and a trendline and correlation coefficient. Insert your mule deer recruitment vs population size graph below. [Insert graph here.] Questions 1. What does the correlation coefficient measure? Strength of relation between two variables. 2. What absolute value signifies a strong correlation? It is a strong correlation between variables if the correlation coefficients measurs greater than .7 3. What does a negative correlation signify? 2

10. What does that say about the relationship between population size and mule deer recruitment rate? As the deer population increases, the recruitment rate decreases. Activity Two You are an ecologist studying algal biomass during eutrophication events. Eutrophication occurs when an excessive amount of nutrients enters a water body, frequently due to runoff, and causes a rapid growth of plants and algae, which leads to a shortage of oxygen in the water and the die-off of other aquatic organisms. You want to determine how the amount of nitrogen in micrograms per liter (µg/L) in the aquatic environment affects algal biomass represented by grams (dry weight) per liter (g-dw/L). You perform a lab-based study using the following nitrogen concentrations (500, 1500, 2500, 5000 micrograms per liter (µg/L)) and collect the following data. Use Excel to calculate the mean and standard deviation. Then complete the table. Time (Day) Nitrogen (Micrograms per Liter (µg/L)) Algal Biomass (Grams (Dry Weight) per Liter (g-dw/L)) Trial 1 Trial 2 Trial 3 Mean Standard Deviation 0 500 .2 .2 .2 0.20 0.00 1 .4 .3 .45 0.38 0.08 2 1.3 1.35 1.27 1.31 0.04 3 1.65 1.6 1.65 1.63 0.03 4 1.8 1.9 1.8 1.83 0.06 0 1500 .2 .2 .2 0.20 0.00 1 .5 .5 .6 0.53 0.06 2 1.25 1.3 1.29 1.28 0.03 3 1.68 1.7 1.65 1.68 0.03 4 1.7 1.9 1.75 1.78 0.10 0 2500 .2 .2 .2 0.20 0.00 1 .6 .5 .55 0.55 0.05 2 1.26 1.29 1.32 1.29 0.03 3 1.75 1.8 1.66 1.74 0.07 4 1.78 1.75 1.9 1.81 0.08 0 5000 0.2 0.2 0.2 0.20 0.00 1 0.65 0.68 0.68 0.67 0.02 2 1.5 1.4 1.5 1.47 0.06 3 1.9 1.9 1.88 1.89 0.01 4 1.5 1.6 1.5 1.53 0.06 4

Calculate Mean and Standard Deviation: Complete the table by using Excel to calculate each row’s mean and standard deviation. The first three are done for you. Use the module resources for Excel to help you complete the calculations for mean and standard deviation. Graph Data Create a graph depicting the effects of nitrogen on algal growth. Label Graph: Make certain a series legend is included showing each nitrogen concentration, and standard deviation error bars are depicted on your graph. Insert your graph below. Include axes labels and include a short, descriptive title. (Hint: Since this experiment was conducted over a period of time, you will want your x- axis to display the Time (Days). Multiple nitrogen concentrations were used in your experiment; therefore, each nitrogen concentration will be represented by its own series. The algal biomass (g-dw/L) was what you measured; therefore, this would be your dependent variable. Include standard deviation error bars in the graph.) Questions: 1. What does the standard deviation measure? 2. Standard Deviation Measures the variation in the data set 3. Standard deviation does not assess statistical significance. However, using the standard deviation error bars in your graph can tell you the likelihood of there being a significant 5