Integrated Environmental Assessment and Management — Volume 10, Number 2—pp. 309–315 ß 2014 SETAC

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Aquatic Ecology Developments affecting northern lakes: a littoral perspective, by Kelly Hille, Katherine Harris, and Zsolt Kovats Littoral monitoring requires easily tested hypotheses that focus on specific characteristics of the attached algal communities.

Learned Discourses Editor Peter M. Chapman Golder Associates Ltd. 200-420 West Hastings Street Vancouver, BC V6B 1L1 [email protected] SETAC’s Learned Discourses appearing in the first 7 volumes of the SETAC Globe Newsletter (1999–2005) are available to members online at http://communities.setac.net. Members can log in with last name and SETAC member number to access the Learned Discourse Archive.

DEVELOPMENTS AFFECTING NORTHERN LAKES: A LITTORAL PERSPECTIVE Kelly Hille,*y Katherine Harris,y and Zsolt Kovatsy yGolder Associates, Calgary, Alberta and Yellowknife, Northwest Territory, Canada *[email protected] DOI: 10.1002/ieam.1516

Aquatic effects monitoring programs for diamond mine projects in the North are required to monitor project-related changes to lake productivity. To date, these monitoring programs have focused on characterizing the chemical and biological conditions at pelagic (open-water) locations (e.g., water chemistry, chlorophyll a concentrations, phytoplankton, and zooplankton). Pelagic monitoring programs make sense in deep lakes, with little to no littoral zones, but the majority of small northern lakes are shallow and have extensive littoral zones. Littoral productivity can have a substantial influence on lake ecosystems. Shallow lakes possess large littoral zones with an abundance of surfaces available for attached algal colonization. Although productivity on a cellular basis is

Environmental Relevance Environmental relevance: a necessary component of experimental design to answer the question, ‘‘SO WHAT?’’, by Chelsea M Rochman and Alistair BA Boxall Why do some investigators continue conducting irrelevant exposures and measuring irrelevant endpoints? Monitoring Using terrestrial mammalian carnivores for global contaminant monitoring, by Esmarie Jooste, Clayton K Nielsen, and Da Chen Terrestrial mammalian carnivores have innate characteristics that make them ideal for contaminant monitoring in terrestrial ecosystems. Management Changes in environmental attitudes of industry: past motivation and future direction, by Gordon R Craig Two major environmental catastrophes in the US provide a graphic example of recent diametric changes in the corporate mindset. DOI: 10.1002/ieam.1531

similar between phytoplankton and attached algae, the large surface area available for colonization in shallow lakes allows for a high contribution by attached algae to the total productivity pool. Bjork-Ramberg and Anell (1985) observed high attached algal densities in subarctic Swedish lakes, where attached algae constituted 70% to 83% of the total lake primary production. In addition, Lodge et al. (1998) determined that attached algal productivity accounted for 95% of whole-lake production in oligotrophic Greenland lakes. Attached algae play an important role in the structure and function of aquatic food webs and are often considered the ‘‘engine of production’’ in shallow lake ecosystems. Although a wide array of fish species rely on C fixed by both attached algae and phytoplankton, aquatic researchers often underestimate the attached algal C contribution to higher trophic levels in most aquatic systems (Vadeboncoeur et al. 2001). The littoral zone provides a link between the catchment area and the open water, acting as both a source and a sink for nutrients. It also has the capacity to recycle and retain an internal nutrient load, which effectively increases the residence time of nutrients within this zone. In contrast, the open-water zone typically requires a sustained input of

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nutrients for algal growth. Attached algal communities possess taxa with well defined growth patterns along defined nutrient gradients (Thomas et al. 2011). This enables them to assimilate and intercept new nutrients within a useful time scale (weeks to months rather than days, typical for phytoplankton), which allows the use of attached algae as a useful biological monitoring tool. Attached algal biomonitoring protocols in rivers have become well established over the past 20 years, but these protocols have not been widely adapted for use in lakes (Thomas et al. 2011). Biomonitoring protocols cover a spectrum in level of effort and costs required, and vary in the precision of results. Rapid visual assessments, chlorophyll a and ash-free dry mass analysis, coarse taxonomic level identification, and pigment assessment by high-performance liquid chromatography (HPLC) require lower sampling and analytical effort than high resolution taxonomic identifications, but the results are less precise and often inconsistent (Thomas et al. 2011). There is evidence that the most sensitive method for detecting changes in littoral attached algal communities is species-level diatom counts. However, all of these existing monitoring methods examine biomass or standing stock of the attached algal community rather than overall primary productivity. Therefore, assumptions must be made, that any changes in standing stock equate to changes in primary productivity, which in turn will affect secondary production. Careful and clear explanations of these assumptions are necessary when making inferences about overall lake productivity and productivity within the littoral zone. The high energy, effort, and expertise required to sample in the littoral zone has often discouraged its monitoring; however, taking the following into consideration during the design of monitoring programs can minimize the difficulty involved in sampling in this area of a lake: 1. What you measure depends on the question; therefore, it is important to identify the key ecosystem properties, i.e., what is valuable to the ecosystem and to humans. 2. Effort should be based on habitat; define the habitat that is germane to the question of interest and value of the ecosystem. 3. Both energy and effort should be expended to emphasize properties important to understanding ecological thresholds and foodweb linkages within the specific system being monitored. 4. The inclination to scale up to whole-lake estimates based on narrow sampling programs should be avoided, unless sufficient resources and energy are expended to deal with the heterogeneity of the littoral zone. One particular diagnostic community that has proven useful in both river and lake ecosystem studies is the epilithon, which is the natural biofilm on rock surfaces. The predominance of rock as a substrate within shallow northern lakes makes the epilithic community a potentially preferable study component for 2 reasons: 1. The rock substrate allows for low-impact, direct measures of community composition and biomass estimates to be performed in situ with minimal disturbance to the area. 2. The inertness of the rock substrate restricts nutrient inputs to the epilithon through the biofilm-water interface rather

Integr Environ Assess Manag 10, 2014—PM Chapman, Editor

than leaching through the substrate, which is possible for attached algae growing on plants, downed woody debris, or in the sediment. Limitations are associated with the epilithic community. Epilithon is not strictly algae, but consists of a biofilm of bacteria, fungi, metazoans, and detritus. Therefore, assumptions must be made about the contribution of algae to the overall response pattern. Epilithon developing on vertical substrata or within areas with considerable wave action is more likely to exhibit nutrient limitation and scouring. This leads to selection for firmly attached taxa, which can bias overall biomass estimates because loosely attached taxa are underrepresented. To match research methods, sampling should be limited to level (

Developments affecting northern lakes: a littoral perspective.

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