The previous chapters have described the theory and methods used to develop InterWET. This chapter will detail the actual InterWET web site. First, a brief overview of the web site contents will be given. That will be followed by information on using the microworlds. The final section will discuss the scope or range of application for InterWET.
5.1. InterWET Web Site Description
Figure 2.4 shows the web pages that make up the InterWET web site. The web site can be accessed through the Penn State Agricultural and Biological Engineering Department at http://server.age.psu.edu/, under research in Natural Resource Conservation and Management (or can be found in Appendix D). The beginning web page the learner enters at the InterWET web site is an "overview" page. In order to go through the InterWET web site, the learner selects a sequence of web pages that focus on water resources or perspectives. Each sequence goes through all the pages in InterWET, but uses a different order. Figure 2.4 shows that the water resources sequence covers all perspectives for one water resource component, then goes to the next water resource component. The perspectives sequence covers all water resource components from one perspective, then goes to the next perspective. To go through the InterWET web site using either sequence, the learner uses the appropriate button, labeled either "Next for Water Resources" or "Next for Perspectives." For most beginning learners, the perspectives sequence is easier to use, because all the web pages for a particular perspective use similar interfaces. The water resources sequence, on the other hand, requires the learner to shift interfaces between each web page.
The InterWET web site consists of web pages to support the 15 microworlds (a microworld is a unique combination of one of the 5 water resource components (surface runoff, groundwater, sediment or erosion, in-stream nutrients, and fish populations) and one of the 3 perspectives (researcher, conservationist, and local official.)) Before getting to the web pages that contain the microworlds, the user goes through web pages that define and inform the learner about each water resource component or perspective. These pages also describe how InterWET addresses each combination of a water resource component and perspective. For example, the runoff introductory page shows a figure of the water cycle, describes the water cycle (including runoff), and details how InterWET will show the learner what different factors affect runoff.
After reading through the appropriate introductory pages for that sequence, a learner then begins to go through the web pages built around the microworlds. In Figure 2.4, these pages are labeled with the water resource component name and a number corresponding to the perspective: researcher as 1, conservationist as 2, and local official as 3. For example, web page "Sediment 2" represents the web page for sediment from the conservationist perspective. The learner uses one of the sequences to go through all of the web pages, learning about each of the water resource components and perspectives. A final web page, not shown in Figure 2.4, contains a brief summary of the concepts covered in InterWET and links to other web sites dealing with hydrology.
Appendix D contains copies of most of the files used for InterWET. This appendix includes all of the web page files in HTML format and all supporting graphic files. Also included are the files used for the calculator microworlds for the researcher and local official perspective in JavaScript format. What is not included are the map microworlds from the conservationist perspective, which require commercial software using Java, and the supporting files with the mapping data.
A learner becomes more knowledgeable about water resources and perspectives by going through the lessons in InterWET. Lessons are included on all web pages that contain one of the microworlds (the numbered web pages in Figure 2.4.) Each of these web pages contains a button to load the appropriate microworld and a lesson that uses the microworld to bring out specific concepts related to that water resource and perspective. The microworld interfaces and contents of the lessons vary depending on the perspective.
The researcher perspective uses calculator microworlds; such as the runoff calculator in Figure 2.2. The lessons from this perspective have the learner experiment with the microworlds to determine how varying levels of the different factors in the calculators will change the water resource levels. For example, the lesson on the web page for runoff from the researcher perspective has the learner vary land cover, soil infiltration rate, and soil moisture levels to determine their impact on runoff levels. All of these web pages conclude with a summary of the relationships between the factors and the water resource component. Appendix A gives a detailed description of each of the researcher microworlds and specific instructions for the use of each microworld.
The conservationist perspective broadens the learner’s understanding of water resources by focusing on the spatial aspect of the data and unique features of a particular watershed. The lessons on these pages display static maps and tables, which list monitoring data for that particular water resource. The microworlds for this perspective consist of interactive maps, using a geographic information system (GIS) representation, that gives a spatial display for some of the monitoring data. The goal of these lessons is to have the learner become familiar with the spatial aspect of the data and unique features of the Spring Creek Watershed. For example, the web page for runoff from the conservationist perspective contains two static maps of the watershed and tables of stream flow, along with a GIS microworld of stream flow at 8 locations in the watershed. The web page’s lesson describes how to use the microworld and has the learner compare the relative contributions of different tributaries, and how stream flow increases towards the watershed outlet. Appendix B gives details on the data sources, methods, and use of the conservationist microworlds.
The local official perspective looks at the impact of local policy decision on changes in water resources responses within the watershed. The web pages contain lessons which compare monitoring data with computer model data, relate local policy decisions to water resource change, and reinforce the relationships brought out in the other perspectives. The microworlds in this perspective are calculators, similar to the researcher perspective, but use policy choices as inputs rather than physical characteristics such as land cover or soil properties. For example, Figure 4.5 shows the calculator used for delivered sediment. The learner discovers how the policy choices affect the different factors covered in the researcher perspective, and how different regional policy choices can affect individual sediment loads in the stream. Appendix C gives details on the use of these local official microworlds.
The web pages and microworlds in InterWET help learners become more knowledgeable about water resources and the Spring Creek Watershed. Like all hydrologic models and educational tools, the range of applicability or scope of InterWET is constrained, because it was developed for one particular purpose, which required the use of many simplifying design features and assumptions. Specifically, InterWET was designed, through a research project, as an educational tool.
As an educational tool for water resources, InterWET uses established hydrologic modeling and computational methods, but also many simplifying assumptions. These assumptions were made to bring out the most important underlying concepts for each water resource component. For example, the lesson on the InterWET web page for runoff from the researcher perspective does not focus on the actual numeric values predicted by the runoff calculator, but on how varying land cover and soil characteristic increases or decreases the runoff values. The values predicted by a microworld on a particular web page are not nearly as important as the concepts implied by these values. The values predicted by microworlds and listed in tables on InterWET web pages should not be used for actual design and decision making. Much more detailed analysis should always be performed when new structures or policies are being considered. This thesis, and InterWET, contain numerous references to original data such as stream flow and groundwater. The use of these data should play a role in decision making. InterWET was not designed to replace the work of scientists and engineers in watershed planning, but rather to help others understand the underlying concepts and relationships used in their work.
In addition, InterWET was designed through a research project, which also required certain assumptions and limitations. InterWET is meant to show how hydrologic modeling could be used for local government level watershed education. The previous chapters have shown the educational designs and theories, Internet modeling techniques, and computational methods that can be used for educational hydrologic modeling. In its present form, InterWET performs an adequate job at demonstrating these ideas.
However, there are a number of things that InterWET is not. InterWET is not a commercial quality software product. The InterWET web site has not been evaluated by anyone beyond those related with this research, and it is known that the web site has some browser compatibility problems. No research was performed to evaluate the educational effectiveness of InterWET’s layout, microworlds, and web page lessons, due to the time limitations of this research project. In addition, InterWET will correctly run all web pages and microworlds for only the 32-bit versions of Netscape 4.0 and 4.5 browsers for Windows. Some brief testing has shown JavaScript compatibility problems with Internet Explorer browsers, JavaScript memory problems with 16-bit Windows Netscape browsers, and Java compatibility problems with Macintosh versions of all browsers. As a research project, the focus of InterWET was to show what was possible, not to make a "bug-free," commercial quality software product.
In addition, InterWET presents only one interpretation of hydrologic monitoring and modeling for the Spring Creek Watershed. The conservationist perspective in InterWET relies extensively on monitoring data and interpretation of monitoring data. However, many of these data sets represent only a small number of measurements or a small range of conditions. The tables in InterWET that summarize these data attempt to denote this idea of "record adequacy." The values listed in InterWET are based on the best available knowledge, which in many cases is very limited. Throughout the conservationist perspective lessons, the emphasis is placed on the fact that much more monitoring data is needed, especially for water quality. The monitoring data shown in InterWET only represents one interpretation of this limited data.
Likewise, the hydrologic modeling performed in the local official perspective uses only one possible model that could be used for the Spring Creek Watershed. There are many different hydrologic models that can be applied to the watershed. InterWET displays the results for one particular set of data for only one of these possible models. The tables on the web pages for the local official perspective does show some agreement between model predictions and the monitoring data. However, for unique features of the watershed like the complex groundwater flow, the hydrologic modeling falls short. As mentioned before, actual technical design and hydrologic modeling for the Spring Creek Watershed should be much more extensive and detailed, using the appropriate methods and models. However, the simplified modeling performed in InterWET was appropriate, as long as InterWET is used solely as an educational tool.
Even though InterWET can not be "All things to all people," it does
show how hydrologic modeling can be adapted for education via the Internet.
The web pages and microworlds work together to help learners become more
knowledgeable about water resources and the Spring Creek Watershed. The
next and final chapter will summarize this research and will detail how
InterWET may contribute to those interested in education, research, and
policy-making related to water resource issues.
