You are here:
CHARACTERIZING STORM HYDROGRAPH RISE AND FALL DYNAMICS AND THEIR RELATIONSHIP WITH STREAM STAGE DATA
Citation:
SHUSTER, W. D., Y. ZHANG, A. ROY, F. B. DANIEL, AND M. E. TROYER. CHARACTERIZING STORM HYDROGRAPH RISE AND FALL DYNAMICS AND THEIR RELATIONSHIP WITH STREAM STAGE DATA. JAWRA. American Water Resources Association, Middleburg, VA, 44(6):1431 - 1440, (2008).
Impact/Purpose:
Information.
Description:
Stormflow transients (i.e., hydrograph rise and fall dynamics) have been shown to impact stream biota through impacts on habitat quality and availability. However, little is known about how climate variability and temporal resolution of transient data may color the putative relationships with stream biota. We first studied potential impacts of rainfall characteristics on stormflow stage dynamics. Next we related these findings and hydrologic indices to physical habitat metrics and stream macroinvertebrate assemblages in eight tributaries of the Little Miami River (Ohio, USA), which drain 17-58 km2 catchments. Stream stage and rainfall were monitored continuously (5 min), and physical habitat was assessed once during the 2002 water year. Benthic macroinvertebrates were sampled once annually from 1999 to 2002, and were characterized with non-metric multidimensional scaling (NMS) and individual metrics. We derived rise and recession rates from storm stage hydrographs by assuming exponential rise and decay of a runoff peak. We found that raw rise rates (Rraw) were correlated with both the maximum rainfall rate and the time to the centroid of a rain event. We removed trend based on these rainfall characteristics, which yielded new representations of rise rates as Rrate and Rtcent, respectively. Fall rates were independent of rainfall characteristics. High rise rates were correlated with % sand and % fines, and slower fall rates were correlated with an increase in % fines, suggesting that stormflow dynamics may have modulated physical habitat. Rraw, Rrate, and fall rates were related to the distribution of macroinvertebrate assemblages from the NMS ordination, with faster rise rates at sites that had higher proportional abundances of intolerant taxa, and faster fall rates at sites with higher proportional abundances of oligocheates and Hirudinea, and higher biotic index scores (i.e, more tolerant individuals). The representation of rise rates as Rtcent imparted a different biotic response, and described a gradient of diversity in macroinvertebrate taxa. Rise rates calculated based on mean daily flows (vs. 5 min) using Indicators of Hydrologic Alteration (IHA) were not related to biotic or physical habitat metrics, suggesting that low temporal resolution data is not adequate to represent the effects of storm rise rates. Conversely, fall rates based on IHA were similar to those based on 5 min. data, and so daily mean data may be appropriate for characterizing fall rates and the relationship with stream biota. Our results indicate that rise rates can be sensitive to rainfall pattern, with implications for the relationship of these hydrologic indices to biota.
URLs/Downloads:
CHARACTERIZING STORM HYDROGRAPH RISE AND FALL DYNAMICS AND THEIR RELATIONSHIP WITH STREAM STAGE DATA
URL.PDF (PDF, NA pp, 22 KB, about PDF)