Unit 1: Recognizing Ecosystem Services and their Relation to the Hydrologic Cycle
In this module, students investigate the ecosystem services associated with local landscapes, particularly in relation to water resources. This unit, the first of three, provides students with the foundational knowledge, tools, and techniques they will need for exploring the services that natural landscapes provide to humans, with a specific focus on assessing the impact of land-use changes on water runoff. In Unit 1.1, students are introduced to the concept of "ecosystem services," and then, using Google Earth, they identify land use and land-use changes that affect those services. In Unit 1.2, students are introduced to some of the technical vocabulary associated with watersheds, watershed hydrology, and the water balance equation; this is accomplished using actual rainfall-runoff data for a small watershed in Ohio as an example. In Unit 1.3, students evaluate the impact of human-induced changes in land cover and land use on watershed hydrology and water balance in the context of ecosystem services.
Learning goal: Students will be able to recognize the range and variety of ecosystem services associated with land use and its relation to the hydrologic cycle.
Objectives to accomplish this learning goal:
- Students will be able to evaluate how the production of ecosystem services varies over time and among multiple land uses and land covers.
- Students will be able to explain the hydrologic cycle using authentic rainfall and runoff data.
- Students will be able to assess human impacts on different components of the hydrologic cycle using a systems-thinking approach.
Context for Use
The activities in this unit are designed to be used in order and together, but they can also be used individually, with slight modifications. These activities would be appropriate in a range of introductory courses, including courses in sustainability, ecology, environmental science, Earth science and geology, land use planning, anthropology, water resources, and landscape design.
Class Size: This unit can be adapted for a variety of class sizes.
Class Format: These activities are designed for individual lecture sessions, but are suitable for use in a lab setting or as a homework assignment as well. Students can work together, in groups of 2–4, but each student should complete his/her own assignment.
Time Required: The activities are designed to be completed in 50-minute class periods.
Special Equipment: Student groups should have a computer with Google Earth installed. If that is not possible, the instructor can print out the information before class. Not every student needs a computer for this unit, but at least one computer must be available for each group. From the instructors' experiences, having at least one computer per three students is ideal.
Skills or concepts that students should have already mastered before encountering the activity: Units and sub-units in this module are self-contained and presume no familiarity with basic concepts of either ecosystem services or the hydrologic cycle.
Description and Teaching Materials
This unit is made up of three activities:
- Unit 1.1: Mapping Ecosystem Services
- Unit 1.2: Exploring the Hydrologic Cycle
- Unit 1.3: Understanding Perturbations to Hydrologic Systems
The first activity introduces students to the concept of ecosystem services and the use of the Google Earth tool. Students then use the tool to explore landscapes and land-use change, and to evaluate ecosystems services provided by those landscapes. The following two activities focus the study of ecosystem services on the hydrologic cycle. Students use authentic rainfall and runoff data to evaluate impacts on ecosystem services associated with land-use change.
Teaching Notes and Tips
The activities in this unit are designed to be used together, in three 50-minute class sessions, but Unit 1.3 could easily be modified to be completed outside of class. Depending on the class, rainfall-runoff data may be developed locally using data from National Oceanic and Atmospheric Administration (rainfall) and U.S. Geological Survey (streamflow) as a class project. The streamflow data was processed using online hydrograph separation tools available from Purdue University.
Assessment activities and associated rubrics are included with each section of the activity. Each of these activities can be included in the class session or assigned as work outside of class.
See the Assessments page for the full list of assessments.
References and Resources
Two readings are included to introduce instructors and students to ecosystem services:
- Millennium Ecosystem Assessment, 2005. Ecosystems and Human Well-being: Synthesis. Island Press, Washington, D.C. and
- Ecosystem Services Fact Sheet (from the Ecological Society of America).
- The Graphic of Wetland Ecosystem Services (Acrobat (PDF) 113kB Apr9 15) can be used as the focus for the class session on ecosystem services.
- A good review of the hydrologic or water cycle is available from USGS.
- In preparation for the activities using rainfall-runoff data, students should read the Watershed Hydrology Literacy (Microsoft Word 2007 (.docx) 1.5MB Aug25 16) handout. This handout defines key terms and concepts associated with the hydrologic cycle, watersheds, and water balance.
- An optional watershed literacy quiz (Watershed Hydrology Literacy Assessment (Microsoft Word 2007 (.docx) 14kB Dec1 16)) can be used prior to or following the class.
- Rainfall-runoff data are included for two watersheds in northern Ohio, Rock Creek and Big Creek watersheds, in table form (Rainfall-Runoff Data and Plot (Microsoft Word 2007 (.docx) 46kB Aug28 15)) and a graph with data from the Rock Creek watershed is included for students to use as a template for analyzing the data.