Spatial and temporal variation in littoral-zone benthic invertebrates from three south-central Ontario lakes

Abstract

Surveys of benthic invertebrates have revealed patterns attributed to the impacts of acid deposition. Unfortunately, these patterns may be confounded by temporal variation that will affect follow-up studies of the recovery of these communities. Here, we assess spatial and temporal variation in time-limited, kick-and-sweep collections of littoral-zone benthos. Spatial variation comprised five sites representing the predominant nearshore substrates in each of three lakes. Temporal variation spanned a different scale in each lake with five sites sampled: (i) twice on the same day, (ii) once a week for 3 weeks, and (iii) four times through the ice-free season. Variation was quantified using a model II analysis of variance. Spatial differences predominated in same-day samples (60.4% of the variation on average) and those collected over a 3-week period (46.1%). In contrast, samples collected over the ice-free season revealed that spatial and temporal factors accounted for 9.4 and 25.6% of the variation. We conclude that our collections of littoral macrobenthos are highly repeatable if sampling is restricted to short periods (e.g., 3 weeks). Surveys spanning longer periods may incorporate considerable temporal variation from seasonal changes in abundance.

Macrozoobenthos structure in a temperate acid oligotrophic lake

“…A similar number of macrozoobenthos taxa was also found in many other acidotrophic lakes in the Czech Republic (Ungermanova et al, 2014), in the Canada (Dermott et al, 1986;McNicol et al, 1995;Reid et al, 1995;Parsons et al Szkokan-Emilson et al, 2010;Wesolek et al, 2010a) and in the USA (Dougherty & Morgan, 1991). On the other hand, in a significant number of acid lakes clearly lower number of bottom fauna taxa were also recorded (Dermott et al, 1986;Kownacki et al, 2006;Parsons et al, 2010;Szkokan-Emilson et al, 2010).…”

Effects of water-depth and water-level fluctuations on the macroinvertebrate community structure in the littoral zone of Lake Constance

“…It is therefore crucial to optimise sampling precision and to take into account other sources of variation. In field studies of the impact of single factors and mechanisms, it is necessary to consider habitat gradients and seasonal changes in the community since they add to the ''noise'' of the data structure by overlapping with the biological signal if their impacts are not known or not considered (Reid et al, 1995;Johnson, 1998).…”

On the role of natural water level fluctuation in structuring littoral benthic macroinvertebrate community composition in lakes

“…Both SolinstH model 2001 and HOBOH model U20-001-01 (Onset) loggers were employed, each logger was surveyed to a reference pin and set to record temperature and water level at hourly intervals 365 d/yr. Biotic and abiotic sampling was conducted in late summer of 2006 during a 4-week period (14 August to 11 September), which limits temporal variation (Reid et al 1995). Each lake was sampled at one location only.…”