Prepare 5.3: Stream Analysis in NC 2024

Prepare 5.3: Stream Analysis in North Carolina Partner Names : Directions : You may complete this activity independently or with a partner (groups of 1 or 2 only). One person makes a copy of the document and shares it with a partner. You will work on the document together in class. If you do not finish in one class block, you will need to complete it during another class block. No one should work on this without the other partner. Each partner must submit the assignment. Make sure to change your share settings to “Anyone with the Link” is an “Editor.” If I cannot see your edits, you will receive no credit for this assignment. Purpose : To examine data sets and make predictions about the state of three watersheds in the Raleigh area. Background Information : The data provided is part of a larger study performed by two field scientists, Lenat & Crawford, in 1994. They examined three watersheds (one in a forested area, one in an agricultural area, and one in an urban area), and collected data. The data included information about the area of the watershed, the water quality of the stream, and an analysis of the bottom sediment in the stream. A map of the three paired watersheds are provided in Figure 1 (to the right). Reference: Lenat, D.R., and J.K. Crawford. 1994. Effects of land use on water quality and aquatic biota of three (3) North Carolina Piedmont streams. Hydrobiologia 294:185-199. Predictions : 1. Identify the scientific question being asked in this study. What are the effects of land use on watersheds? 2. Identify the location that is the control in this experiment. Explain why you chose this location. The control in the experiment is the amount of nutrients the water has in it. Specifically the one in the urban area, since it's much further away from the other two. This 3. Hypothesis : After reading the background information and the data provided below, identify a hypothesis for this experiment, being sure to clearly identify both the independent and dependent variables. The watershed in the agricultural area will have the highest water quality. The dependent variable being the quality of the water along with the sediment and the independent variable being the location of each watershed.

Data: Table 1: Comparison of Watershed Characteristics in North Carolina Watershed Study Characteristic Forest Watershed Agriculture Watershed Urban Watershed Name Smith Creek Devil’s Cradle Creek Marsh Creek Area (square miles) 6.2 2.9 6.8 Forest Cover 75% 31% 24% Agricultural Cover 21% 53% 5% Urban Cover 4% 13% 71% Riparian Cover Forested Mostly Forested Mostly Forested Stream Order Second Second Third Point Sources? None None None Other Influences Upstream beaver dam may have trapped sediment No stormwater practices were used to treat agricultural runoff No stormwater practices were used to treat stormwater runoff Table 2: Comparison of In-Stream Water Quality in Study Watersheds (Crawford & Lenat, 1989) Stream Water Constituent a Forest Watershed Agriculture Watershed Urban Watershed Total Phosphorus b 0.09 0.27 0.10 Dissolved Phosphorus <0.01 0.05 0.02 Total Nitrogen 1.70 2.11 1.42 Dissolved Nitrogen 0.08 0.59 0.41 Total copper ( μ g/L) 7.9 5.0 12.5 Total lead ( μ g/L) 5.1 6.6 14.4 Total zinc ( μ g/L) 31 23 39 Mean Stream Temp. c 57 58.9 60.1 Max Stream Temp. 72.5 73.4 77.0 Sediment Discharge d 0.13 0.31 0.59 a Mean of 12-14 baseflow samples b Nutrient units are mg/L c Degrees Fahrenheit d Summed product of daily flow and watershed-specific suspended sediment Table 3: Analysis of Bottom Sediment in Study Watersheds (Crawford & Lenat, 1989) Forest Watershed Agriculture Watershed Urban Watershed Gravel (greater than 2.0 mm) 35.0% 7.5% 27.0%

the most species richness. The watershed with the best water quality and best land quality are the ones that are affected by the effects of urban sprawl. Without it, there is more chance for sediments to flow rather than preventing it like urban sprawl does.