Patterns of macroinvertebrate assemblages in a long‐term watershed‐scale study to address the effects of pulp and paper mill discharges in four us receiving streams

Abstract

Changes in macroinvertebrate communities exposed to pulp and paper mill effluent (PPME) have been seen in mesocosm and short-term field studies. However, long-term patterns of macroinvertebrates in PPME receiving streams have not been examined. We conducted a study of 4 PPME receiving streams (Codorus Creek, PA; the Leaf River, MS; and the McKenzie and Willamette rivers, OR) over 9 y to assess temporal patterns in macroinvertebrate community structure and metrics related to PPME discharge. Study streams represented different ecoregions, warm-/cold-water systems, gradients of PPME concentration (<1%-33%), and mill process types. Bray-Curtis similarity and nonmetric multidimensional scaling showed significant community differences across sites in Codorus Creek, but differences were related to stream temperature patterns and not PPME. In the other study streams, seasonal community differences across years were greater than differences across sites. General linear models were used to examine spatial and temporal variation in macroinvertebrate metric response (% dominant taxa, density, richness, Hilsenhoff Biotic Index [HBI], Simpson's Index, and ash-free dry mass). Mean HBI scores indicated that the macroinvertebrate community reflected fair to very good water quality conditions, with water quality typically classified as "good" at most sites. Significant site differences in macroinvertebrate metric response were uncommon in the Leaf, McKenzie, and Willamette rivers but were seen in all metrics in Codorus Creek, where metric response was spatially variable. In the McKenzie River, there was an increase in mean HBI scores at sites downstream of the mill relative to 1 of the 2 upstream sites. However, significant differences were seen only between 1 upstream and downstream site, and HBI scores at all downstream sites consistently reflected "good" water quality. Significant annual differences in metric response were typical in all rivers. Water quality (pH, conductivity, total nitrogen) and habitat (velocity, depth, substrate composition) variables explained community structure patterns in the Leaf and McKenzie rivers, but macroinvertebrate-environment relationships were weak in the other 2 streams. The results of this study indicate that macroinvertebrate community structure is temporally variable and reiterate the importance of long-term studies for accurate determination of the effects of point sources such as PPME on receiving systems.

Patterns of fish community structure in a long‐term watershed‐scale study to address the aquatic ecosystem effects of pulp and paper mill discharges in four us receiving streams

“…Torrent sculpin and Paiute sculpin are classified as “stress intolerant.” These 2 taxa dominated upstream sites but decreased in abundance downstream as intermediately tolerant taxa increased. In a concurrent examination of the macroinvertebrates in these streams, the macroinvertebrate community downstream of the PPME discharge in the McKenzie River reflected good water quality conditions, although a similar increase in the relative abundance of more tolerant taxa at downstream sites was seen in macroinvertebrate taxa, suggesting reduced water or habitat quality relative to upstream sites (Flinders et al 2009b).…”

“…An absence in community response in the 4 study streams might be because of the high variation seen both spatially and temporally during the study. However, effluent‐related biological effects were rare in periphyton biomass (Flinders et al 2009a) and macroinvertebrate community structure (Flinders et al 2009b). Similarly, the response of fathead minnow ( Pimephales promelas ) during life cycle exposures to PPME discharged into the LTRWS streams showed no effects at the in‐stream effluent concentrations in each of the 4 study streams (Borton et al 2009).…”

“…Model variables for large‐bodied fish in the Leaf, McKenzie, and Willamette rivers included water chemistry characteristics of pH, color, conductivity, TP, and TN. In Codorus Creek and for small‐bodied fish in the McKenzie and Willamette rivers, model variables included water chemistry characteristics (pH, color, conductivity, TP, TN) as well as physical habitat variables (depth, velocity, and % substrate composition) (Flinders et al 2009b). For each stream, community data were pretreated as described above for ANOSIM analysis, and environmental variables were standardized to the mean and standard deviation.…”

Introduction to special series: Measurement and analysis of the potential long term impact of pulp and paper mill effluent on receiving waters

“…Flinders et al (2009a) describes spatial and temporal patterns of periphyton development (chlorophyll a ) on the study streams and the extent to which these may be related to effluent exposure as contrasted to expressions of natural variability or non‐mill‐related factors. Similarly, Flinders et al (2009b) report on the examination of macroinvertebrate community structure and multimetric indices above and below paper mill discharges on each waterway, as well as large and small bodied fish community structure metrics. Flinders et al (2009c) report on sustain‐ability and reproductive viability of fish populations through long‐term multispecies community level monitoring.…”

Water resource use and management by the United States forest products industry

“…These responses have been attributed to increased nutrient concentrations and primary production (Lowell et al 1996;Culp et al 2003), although increased macroinvertebrate biomass is not always reflected in primary productivity (Dubé & Culp 1996). Macroinvertebrate data collected during the LTRWS between 1998 and 2006 showed differences in community structure across sites, but no changes downstream of forest products industry discharges relative to upstream sites (Flinders et al 2009b). Seasonal and annual variations in macroinvertebrate metric responses (e.g.…”