Watershed Science: Working with biogeochemical data in a first-year undergraduate seminar.
Rachel O'Brien Department of Geology, Allegheny College
This is a partially developed activity description. It is included in the collection
because it contains ideas useful for teaching even though it is incomplete.
This is a first-year college course on water and N cycling that involves four active-learning projects utilizing datasets collected by the students and taken from published sources. It teaches fundamental scientific principles (application of mass balance equations to study natural systems) as well as effective communication skills (preparing figures/tables, writing persuasively). The students prepare a complete scientific report at the end of each project.
GSA Poster (PowerPoint 30MB Oct31 03)
Higher Order Thinking Skills:
Synthesizing multiple data sets to draw conclusions
Identifying multiple lines of evidence to support an interpretation
Developing a testable hypothesis
Algebraic calculations and unit conversions (by hand and on a spreadhseet)
Preparation of effective figures and tables
Improved professional writing skills
Undergraduate entry level. Could be expanded to an undergraduate major course if less emphasis were placed on communication skills and more development of topical content was provided.
Since this is a first-year course, there is not much that they students have already mastered. I tell them (in the course description and then again on the syllabus) they must be able read and understand simple chemical equations. (High school chemistry would prepare them for this.) They also must be able to use simple math skills–such as manipulating algebraic expressions and working with logarithms.
Role of Activity in a Course:
The four projects constitute an entire 16 week course.
Data, Tools and Logistics
For Projects #1 and #4, you'll need simple field equipment: Sample bottles, stopwatch, measuring tape, soil coring equipment, a balance, a Hach nitrate kit.
For all projects (1-4) you'll need computers with spreadsheet/plotting software and internet access.
1) It's important to put a lot of effort into the first unit to get all students well grounded in the basic principles of a water budget. The water and N budgets get increasingly complex throughout the course. This means being available for students with weak initial skills.
2.) If you allow students to conduct an independent field project for Unit #4, be prepared to help them with all of the logistics!
3) For students will weak computer skills, offer "outside" computing help sessions. This preserves class time for the more important content issues.
I'd love to interview students 1-3 years after they've taken the course, to determine if they have continued to use the higher order thinking skills they practiced in the course.
I use a course-specific form to assess how much the students feel they've learned. (This is provided to them at the same time as a College-wise assessment form.) I design the form around the measurable goals & activities listed on the course syllabus.
The course is designed around 4 activity-based research projects that examine water and nitrogen budgets for a variety of watersheds. The questions for the first 3 projects are provided by me; students develop their own research question and project for the final unit. Each project builds on the skills and insights we've learned–so the complexity of content and analysis increases throughout the course. A brief synopsis of each unit follows:
Unit 1: What is a watershed? Field-based investigation of a local (~1 ha) watershed. Students identify reservoirs and fluxes of water and construct a simple annual water budget. (Data collected by students and local authorities.)Written report.
Unit 2: What is the major source of N to the Mississippi River? Students calculate water and N budgets for 3 sub watersheds with different land use in the Mississippi drainage basin to test the hypothesis that agricultural practices constitute the major source of N. (Data from published NOAA report.)Written report.
Unit 3: How to water and N budgets change when a forest is clear cut? Students calculate water and N budgets for a forest at the Hubbard Brook Experimental Forest (NH), then create testable hypotheses on how those annual budgets will change if the trees are removed. Using archival data posted on a website, students obtain data after a clear-cut and analyse it to compare with their predictions. (Data from LTER website.) Written report.
Unit 4: Student-designed research project. Can be at any spatial scale–local to global. Must include a water and solute budget (not necessarily nitrogen). Students must have their research question and hypothesis approved before they complete the project. Oral presentation (7-9 min.) plus written report.