An Index for the Delaware - Exel: Drexel University's Research Magazine
 
 

_FEATURE A WATERSHED MOMENT Biology

_An Index for the Delaware

One way to assess impacts to an ecosystem and express it to the public is to compile biological indicators, like fish and algae, into an index called the Index of Biotic Integrity (IBI).

_Stefanie Kroll

Kroll is the project science director of the Delaware River Watershed Initiative at the Academy of Natural Sciences of Drexel University.

One simple way to assess impacts to an ecosystem and express it to practitioners and the public is to compile biological indicators, like fish and algae, into a summary index called the Index of Biotic Integrity (IBI).

However, no such index exists for the Delaware River watershed as a whole, because the basin runs through four states with their own individual approaches.

Academy scientists are working to change that. Stefanie Kroll, project science director for the Delaware River Watershed Initiative, and a team of Academy scientists in collaboration with the Stroud Water Research Center in Avondale, Pennsylvania, are visiting streams and sites to investigate how certain bioindicators relate to degradation and conservation efforts.

Getting_a_Grade

Scientists are compiling an “Index of Biotic Integrity” that summarizes the biological well-being of the Delaware River watershed as a whole.

“This work is generating information on the Delaware River Basin and using local waterways to answer questions about watersheds on both regional and local scales, like ‘Which areas should be prioritized for conservation?’ or ‘Where can we target conservation actions so they have a cumulative effect on improving or maintaining water quality?’” she says.

To further their knowledge of the effect of conservation efforts, Kroll and other scientists are also looking into how water quality is affected by stream connectivity and tributaries that flow into larger streams. They will target certain places along the river where tributaries connect to larger streams or to pollution “hotspots.”

Altogether, the work will measure the effects of restoration and protection on water quality, and help target where these practices can have the greatest positive impact, according to Kroll. The next step is to understand how researchers can best use these approaches to determine the biggest stressors to regional streams.