Responses of freshwater biota to human disturbances: contribution ofJ-NABSto developments in ecological integrity assessments

Abstract

Effective ecosystem management in the face of human alterations depends on our ability to quantify ecologically significant changes and to discriminate among impact levels and types. We reviewed the literature on biological responses of freshwater biota to human disturbances over the last century. Many of the main methods for assessing ecological integrity originated in Europe [e.g., Saprobien Index, Trent Biotic Index, Biological Monitoring Working Party, River InVertebrate Prediction And Classification System, multiple traits] or in North America [e.g., Index of Biotic Integrity, leaf-litter breakdown, functional feeding groups]. We used bibliometric data to detail the contribution of J-NABS to developments in assessment of ecological integrity. A total of 225 bioassessment articles were published in J-NABS from 1986 to 2007. This total was ,½ of the number of bioassessment articles published over the same period in Freshwater Biology (FWB; another leading freshwater journal used for comparison), but the proportion of bioassessment articles in the 2 journals was similar (,20%). The proportion of bioassessment articles in J-NABS has increased over the last 25 y. This trend indicates the growing interest in the topic and the delay (,30 y since the Clean Water Act) of scientific action in response to water legislation. Taxonomic composition and multivariate techniques, multimetric indices, lotic systems, macroinvertebrates, land use, and overall human impacts were major themes in J-NABS bioassessment articles. Progress in bioassessment is needed in 3 main areas. First, bioassessments done at large spatial scales are needed to meet requirements of new environmental policies. Second, bioassessment should shift from consideration of taxon losses to losses of ecological functions. Third, statistical techniques are needed for predictive assessment of deviation in ecological integrity between expected (natural) and observed (natural or impacted) conditions. Assessment of functional integrity based on multiple traits is a promising area because biological traits represent universal biological characteristics that are connected to ecosystem functions. However, the relationships between ecophysiological traits of individuals and ecosystem-scale responses must be properly defined for specific types of human impairment, and utility of the approach for routine bioassessments applied by managers must be tested.

Assessing contaminated sediments in the context of multiple stressors

“…A promising new assessment tool, particularly for benthic invertebrate-based ecosystem quality assessments, is the use of biological traits (morphological or functional) to develop geographically broad (continental) lotic ecosystem assessments of dominant stressors [196,219,[268][269][270][271]. This approach may assist in discerning effects that are due to the physical presence of solids, as opposed to solids-associated chemicals.…”

The role of a discipline-specific journal in scientific discovery

“…Winemiller et al (2010) addressed this topic explicitly. They described how both temporal and spatial variation influence patterns and processes in streams at virtually all scales, and how a better understanding of the effect of this variability could improve the rigor of bioassessment (Dolédec and Statzner 2010) and benchmark assessments (Hawkins et al 2010). Spatial heterogeneity also was a major theme in the review by Johnson and Host (2010).…”

“…Theoretical advances from other systems permeated the papers on disturbance (Stanley et al 2010) and patch dynamics (Winemiller et al 2010), but comparisons among systems were rare with the exception of Benke and Huryn (2010). Stream ecologists have led other ecological disciplines in the development and application of biotic indices to assess ecosystem condition (Dolédec and Statzner 2010, Hawkins et al 2010 and in quantifying secondary production (Benke and Huryn 2010).…”

The influence of environmental factors on the structure of caddisfly (Trichoptera) assemblage in the Nišava River (Central Balkan Peninsula)

“…Shifts in food sources can directly or indirectly change the quality and quantity of available food resources for macroinvertebrates (Culp, 1987). The source of energy in streams changes seasonally, with loss of natural riparian cover, and as a result of anthropogenic inputs of inorganic and organic compounds (Sponseller and Benfield, 2001;Paul et al, 2006;Dolédec and Statzner, 2010;Tank et al, 2010). In temperate climates, ecologically relevant factors (flood disturbance frequency, bottom substrate type, discharge, temperature, light, salinity, etc.)…”