New GIS and FQA Tools
08 July 2009 - 04:14
We’ve finally gotten around to adding some tools to the site that we’ve been thinking about for quite a while. These tools enable users to define areas of interest at a geographical location using a Google Maps-based mashup and to conduct floristic quality assessment studies on those areas.
Here’s a brief explanation of what this means (until we get around to writing more complete documentation).
Geographical Information System Tools (GIS)
Anyone doing serious study of lands such as remnant prairies needs to identify specific parcels or locations on those lands — for doing inventory studies, marking particular plants or landforms, etc. Professionals and those with big budgets typically use a very expensive computer application called ArcGIS from ESRI though there are a number of open-source GIS apps out there as well.
These apps allow users to combine geographical imagery (from maps) with data about what lies on the geography to do a variety of kinds of analysis — hence their name “geographical information systems” (GIS). One probably with these tools — which are mostly desktop applications — is where to obtain the maps. Another issue is how to share the analyses.
For this Remnant Prairies web site, our GIS needs are fairly limited, so a form of “GIS-lite” would suffice. We want to be able to define polygonal regions (for survey work), lines (for marking landmarks or transect studies), and markers (for specific plants or other landmarks) — in other words, annotations more than analysis at least in terms of the map data.
It turns out that Google Maps can be made to serve all those functions very nicely, plus it provides as detailed imagery as one could hope for. Google Maps was thus the obvious choice to use for our GIS-Lite system here. You can see how it works by going to the Locations section.
We can define multiple locations which basically are simply a map centered on a particular latitude and longitude. We’ve created a demo location on the Konza Prairie. There you’ll see a satellite view (courtesy of the USDA FSA via Google) where you can zoom in/out, move around, and otherwise explore just like any Google map.
Superimposed on the map are several “georegions” as we’ve decided to call them — one “region”, one “line”, and one “marker”. These were created using the three buttons at the top center of the map. Details about how to create new georegions are at the bottom of the location page. You can see which georegion is which simply by running your cursor over one and noting which name in the list to the right of the map highlights yellow. When you alter a georegion, its name in the list will be highlighted red — indicating that the changes need to be saved — after which the name will revert.
Clicking on the names of the georegions takes you to a page for each of them. There several kinds of information can be reviewed and edited — the name of the georegion, its description, and a series of comments (to support discussion about the georegion). Of course, being a web application, all of this information is available to anyone with an Internet connection. (Well, these public locations are; locations created within Groups inside the site are accessible only to members of those Groups.)
Thus this GIS-Lite system provides substantive GIS features without the need to install or understand any GIS applications on your desktop.
Floristic Quality Assessment (FQA)
For Region georegions, we’ve added an additional set of online tools to manage floristic quality assessment data. FQAs basically report the “goodness” of a given piece of land by making calculations from the specific species that are found there.
These calculations are based on assessments made by expert consensus about the relative “conservatism” of each species — measured on a scale of 0-10, where 0 is least conservative (ie most weedy/invasive/exotic) and 10 is most conservative (ie most native/crucial to the biocommunity). A variety of measures can be defined in addition.
The FQA approach has been around for a couple of decades, but it has been most thoroughly developed by Craig Freeman and colleagues at the University of Kansas, whose algorithms we implemented here.
Prior to making these calculations, one must record the species identified during a given FQA study. To this end, we’ve also implemented a plant database here. This database is searchable and browsable, and contains the detailed ecological data used in the FQA processing. This database does not include the kinds of descriptive/diagnostic information common to guidebooks, but it does provide links to Google searches both for links and more usefully to the Google Images databases — so this plant database is rather useful in its own right.
If you go to the Research Plot 1 demo georegion at the Konza location, you’ll see a link to the summary of its FQAs which shows serial studies over time in a fashion that makes it easy to spot trends.
From there you can drill down to a specific study (such as July 2005) where there are detailed tables of all the data. One particularly nifty feature is the “Coefficient of Conservatism Tallies” section, where there are links that lead to lists of the particular plants in this study that have a given coefficient — which is useful when you wonder “what CoC 8 plants do we have here anyway?”. There is a printer-friendly version in case you want a printout.
It’s very easy to create and update these FQA analyses. For instance, the edit page of the July 2005 study is where you add in plants, add in sets of plants from prior studies, and remove plants. Once you’ve finished adjusting the plants in the study, simply returning to the main page for the study shows the immediately updated calculations.
So, with this combination of tools, we think that there really is no reason that anyone who owns or manages a piece of prairie should be doing regular quantitative analysis of their lands. We’ll gladly set up new groups at our site for this purpose. Post a comment here if you’re interested!