Description

GEOG 205 Fall 2020 – Lab 3: Watersheds and Rivers

Introduction

In Lab 3 you will learn more about watersheds and rivers. Rivers are the most important erosional agent on earth, as they transport the majority of sediment to the oceans and therefore are responsible for impressive amounts of landscape denudation. From concrete urban channels to massive rivers like the Mississippi that drain parts of entire continents, the flow of channelized water is all around us. River processes and landforms are thus both incredibly important and ubiquitous, and Lab 3 will provide you with hands-on understanding of these landforms and how they organize into watersheds (and who knows, maybe you’ll have to get your boots wet too!).

Learning Objectives

·         Visit your local river and learn how to put small-scale observations in the context of river processes and patterns observed with larger scale maps and imagery.         

o   Interpret and understand how humans modify river systems.

·         Use watershed assessment tools to improve understanding of watershed processes and structure, while gaining experience with plotting, visualizing, and interpreting experimental and numerical modeling data.

·         Use imagery, existing data, and fundamental published literature to explore river channel patterns.

Instructions and Notes

Make sure to download the file called “g205f20_Lab3Data.kmz” from the week 6 lab content LEARN submodule.

·         Lab 3 is worth 18% of your lab grade, and thus 9% of your total course grade.

·         Please show your work if applicable.

·         Cite all external references used – directly pasting phrases from the internet will result in a grade of 0 for the entire assignment. You should cite these sources in a reference list at the end of the report, but also use in-line citations when appropriate.

·         Subsections of labs are listed with numbers, questions that must be answered are listed with letters. So for example, you must answer questions 1.a., 1.b., and so on.

·         Submit in either Word or PDF format, and number your responses in the same way they are numbered here. Please put your name and ID number on your assignment. Instructors and TAs don’t like being confused by the submission format!

Lab 3 Questions (44 total marks)

1.      (11 marks) Visit your local river – whether it is an urban stream near your house, a wild and beautiful braided river in the Canadian Rockies (yeah, right), or a small meandering creek in a nearby park.

a.       Find a place along the river where it is safe and legal to be, and take a photo or two of the river. Then, find a map of the same location (you can use Google Earth, a GIS, or any other software you are familiar with). Make sure your map is legible and appropriately shows where you took your picture (for some hints on what a good map might include, go here). (1 mark for photo, 3 marks for map).

[insert photo here]

[insert map here]

b.      Judging by your photo and map, is your river mostly straight, meandering, braided, or something else? Why do you think that pattern prevails? (2 marks).

c.       Browse the Gregory 2006 paper in the Readings subcontent module in Week 6. In particular, see Table 3 to learn about the different between direct and indirect river impacts. In either your map or photo, point out one location of a visible direct modification of river process and/or form. Please circle, draw an arrow to, or otherwise annotate this direct modification and explain what the modification is and what affect it might have on the river (3 marks).

[insert map/photo with annotation here]

d.      Explain one indirect modification of river process or form that can be inferred from your image or map. Explain what the modification is and what affect it might have on the river. (2 marks).

2.      (19 marks) Access the Ontario Flow Assessment Tool here. Learn a bit about how to use the tool by reading about it under “Steps to run the Create Watershed tool” on the previously linked page. Play around with the tool a little by clicking the “Access the Ontario Flow Assessment Tool”, and get some experience using it before attempting the following questions.c