Help Using the Graphical Vegetation Database Browser

About the Graphical Vegetation Database Browser

The graphing software used for the Graphical Vegetation Database Browser was written using Java Applet technologies. To work on your computer, your Web browser must have java enabled. The graphing software displays data for the Long Term Resource Monitoring Program field stations at the same time. The user then can choose one of the graphs to be displayed in more detail in the main window. The software also allows for printing and for creating a comma-delimited text document of the data that can be saved to the user's computer.

Using the Graphical Vegetation Database Browser

Above is a display of output from the graphing tool. The display is divided into two regions, the left column and the main window. In the left column, small graphs (one for each field station) are displayed. The main window displays the active graph and its associated data table. To change the active graph, point the mouse arrow at the smaller version of the graph in the left column. This highlights the chosen graph, displaying it in the main window. To see a numerical value on the graph in the main window, use the mouse to point to the location on the graph that you want to see the value for or point to a specific year or value in the table. To print a graph, use the dialog box below the main window (shown here):

Select which graphs you wish to print by clicking on pools in the drop-down box, if you hold the control key while selecting pools, multiple selections can be made. Now click on the "Create Charts" button. The selected graphs displays in a new window. Within this new window, click the print icon of your browser and the graphs will be printed, one per page. You may be able to print from the main window, but results are unpredictable depending on the browser and printer used. Another feature provided on the main window is the ability to create a comma-delimited text document by clicking the link below the printing information. This opens a new window containing a text document with header information followed by the data for all six field stations. You will have to save this page by clicking the "File" menu followed by "Save as." Give the file a name and location to be saved then change the file type from .html to .txt and click "Save." You can import the comma-delimited text file into other applications for custom graphing or statistical analysis.

Enabling Java in Internet Explorer and Netscape Navigator

Internet Explorer

1. Click "Tools"
2. Click "Internet Options"
3. Click "Advanced"
4. Check the check boxes under the Java category

Netscape Navigator

1. Click "Edit"
2. Click "Preferences"
3. Click the "Advanced" option
4. Click the "Enable Java" option

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Strata

• Main Channel Border
• Side Channel Border
• Backwater Contiguous
• Backwater Isolated
• Impounded
• Lake Pepin
• All Strata

The LTRMP stratifies vegetation sampling by depth as well as across six strata, characterized by enduring geomorphic and physical features. All sampling points are located in water less than 2.6 m deep. Several strata are further divided within Pool 4 (main channel border, side channel, contiguous backwater, and Lake Pepin) and Pool 26 (main channel border, backwater isolated). Pool 4 is divided by a line through Lake Pepin at river mile 775 into upper and lower sections. These two sections display distinctly different vegetation dynamics. The lower 12 miles of the Illinois River is sampled along with Pool 26. This area is analyzed separately from the rest of Pool 26. The LTRMP vegetation sampling strata are defined as follows:

Main Channel Border

Aquatic areas between the margins of the main navigation channel and the nearest shoreline (island or mainland) excluding dams, lock walls, and wing dams.

Side Channel

Backwater Contiguous

Backwater contiguous is characterized by having some connection by water to the main navigation channel but is separated from the main channel by a terrestrial area and does not carry flow at normal river elevations. Backwaters may consist of floodplain depression lakes, sloughs, lateral levee lakes, bays, and artificial lacustrine areas.

Backwater Isolated

Backwater isolated is characterized by having no connection by water to the main navigation channel, but may be connected during floods.

Impounded

Impounded areas are large, mostly open-water areas located immediately upriver from locks and dams. Water elevations are held above preimpoundment levels by the dams. Impounded areas may contain submerged channels and areas that were terrestrial before impoundment.

Lake Pepin

Lake Pepin is a large natural lake in Pool 4 that was created by the Chippewa River delta.

All Strata

Within the Graphical Vegetation Database Browser, strata listed above represent a spatially defined area of a study reach that is smaller than the study reach itself. Estimates from each of the stratum listed above are "pooled" and appropriate "weighting factors" are applied to derive an unbiased estimate for the entire study reach from the collection of strata-specific estimates. Thus, the ALL strata represents an unbiased estimate at the study reach scale, which is larger in physical size than the stratum.

Life Forms

• Submergent Species
• Rooted Floating-leaf Species
• Emergent Species
• Filamentous Algae

Submergent Species

All parts of the plant are below the surface of the water. Some plants extend the flower or fruit above the surface. Some pondweeds have submersed and floating leaves but are included in the submergent life form.

Rooted Floating-leaf Species

The roots and stems are buried in the sediment. Leaves and flowers float on the surface of the water or occasionally rise above the surface.

Emergent Species

The roots are buried in the sediment whereas the stem, leaves, and flowers rise out of the water.

Filamentous algae

A nonvascular plant that looks like strands of green hair. It often covers other aquatic plants.

Metrics

• Percent Frequency
• Relative Frequency
• Abundance Index
• Percent Cover
• Distribution Maps
• Species List
• Community Composition
• Community Similarity
• Species Evenness
• Species Richness
• Species Information

Percent Frequency

Percent frequency is a measure of how often a species is encountered. It is calculated by dividing the number of sites where a species occurs by the total number of sites sampled and multiplying by 100. It is displayed as a bar chart by year.

Relative Frequency

Relative frequency compares the frequency of one species to all species. It is calculated by dividing the number of occurrences for a single species by the total number of occurrences for all species. It is displayed as a pie chart representing 1 year.

Abundance Index

Abundance index measures the quantity of a submersed species using both presence, absence, and the plant density rating. Abundance index is only measured for submersed species.

Percent Cover

Percent cover measures the amount of surface area rooted floating-leaf and emergent species occupy based on a cover rating.

Distribution Maps

Querying for distribution maps allows you to view where species or life forms were found for a certain period and pool. It produces a map with the species or life form locations for each year in the range selected.

Species List

Species list is an alphabetically arranged list of species collected by the Long Term Resource Monitoring Program since 1998. The species are sorted by life form.

Community Composition

Community composition is an alphabetically arranged table portraying species representation in each of the study areas separated by life forms.

Community Similarity

Community similarity is a measure of how similar the study areas are based on vegetation species. The table includes the total number of species recorded in each pool, the number of species that were recorded in both pools and a similarity index. The similarity index is calculated using Jaccard's coefficient.

Species Evenness

Querying for species evenness allows you to compare diversity of vegetation in the pools based on the number and frequency of species present within each study area. It allows you to query based on life form and a year range. The diversity index and evenness are calculated using Shannon's Diversity Index where a value close to 1 means the pool is diverse and a value close to 0 means the pool is not diverse.

Species Richness

Species richness is a measure of the diversity within each study area. The total number of species observed each year is plotted as a time series for each study area.

Species Information

The vegetation species information page provides the common name, scientific name and family for each species collected by the Long Term Resource Monitoring program since 1998. Species are sorted by life form.

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