Influence of environmental factors on the distribution of caddisfly (Trichoptera) communities in medium-sized lowland streams in Latvia

Abstract

The understanding of community structuring factors is a fundamental issue in community ecology. The objectives of the study were (1) to identify the distribution of the caddisfly community along the stream continuum; (2) to ascertain hydrochemical, hydrological, substrate, and catchment factors responsible for the distribution of communities; and (3) to summarize the key variance types determining the variance in caddisfly communities. Standard methods were used to investigate hydrological and hydrochemical parameters of nine medium-sized streams in 2003. Sampling and processing of samples of macroinvertebrates followed AQEM methods. A total of 28 taxonomic units of caddisflies were analysed. The upper reaches of streams revealed a relatively low abundance of caddisflies while the middle reaches had high abundances. The abundance in the lower reaches varied in a wide range. TWINSPAN separated the caddisfly species into two distinct groups. One group represented lithal habitat and rheophilous species. The other represented stream reaches with fine mineral sediments rich in organic matter of different size. Hydrochemical and physical variables explained the majority of variance in the preferences of caddisflies to bottom type and other environmental parameters, while all studied variables together explained up to 58% of the data variance. Thus, caddisflies could be used to study the influence of local and regional factors on stream ecosystems. The results of the present study could be also applied in practice to solve problems related to the evaluation of the ecological quality of running waters using benthic macroinvertebrates.

Storage reservoirs beyond a lake district as secondary habitats for caddisflies (Insecta: Trichoptera) in an area of karst origin (SE Poland)

“…The most important were the physical and chemical parameters of the water, followed by structural factors; the least important were factors associated with buffer zones. A number of authors (Galbraith et al, 2008;Skuja and Spungis, 2010;Savić et al, 2013;Buczyńska et al, 2017) consider the parameters of water to be of greater significance than the water body's structure and/or its surroundings/ catchment area as regard the distribution of caddisfly larvae in natural waters. Even though the percentage of explained variance in each category of factors obtained by those authors and in the present work is not always high (9-40%), it is clear that these insects À as expected from their mode of life À are affected by factors acting at different spatial levels.…”

Bryophyte diversity in karst sinkholes affected by different degrees of human disturbance

“…The correlation between bryophytes and heterogeneous environmental factors was analyzed using canonical correspondence analysis (CCA). The significance of the environmental variables was determined using a forward selection with the Monte Carlo permutation test (999 permutations, p ≤ 0.05) [37]. The website Draw Venn Diagram [38] was used to prepare Venn diagrams of the bryophytes species in the five sinkholes.…”

Interacting influences of climate factors and land cover types on the distribution of caddisflies (Trichoptera) in streams of a central European low mountain range

“…Those adaptations that differ among species may facilitate habitat partitioning, in addition to other factors, like flow rate, food, pH, or substrate (e.g. Mackay & Wiggins, ; Urbanič et al ., ; Gombeer et al ., ; Skuja, ).…”