Potential for Trichoptera communities as biological indicators of morphological degradation in riverine systems

Abstract

Many rivers in southern Africa are increasingly threatened by accelerating geomorphological degradation due to unsustainable agricultural practices and deforestation. Thus, there is a critical need for biological indicators of morphological degradation in running waters. This study analysed the composition and abundance of Trichoptera taxa from 32 sites from rivers in eastern and northwestern Zimbabwe in relation to geomorphological and land use parameters. Redundancy analysis (RDA) and Spearman's rank correlation analysis revealed that species in the genera Anisocentropus, Dyschimus, Lepidostoma, Leptocerina, Athripsodes, Parasetodes, Aethaloptera, Hydropsyche and Polymorphanisus were restricted to undisturbed forested sites, suggesting that these Trichoptera taxa may be used as indicators of structural degradation in watercourses. A species in the genus Hydroptila was the only Trichoptera taxon that showed a statistically significant numerical abundance at disturbed agricultural sites.

A Methodology to Model Environmental Preferences of EPT Taxa in the Machangara River Basin (Ecuador)

“…However, Ríos-Touma, et al [11] reported that this variable is less important for macrobenthos with faster development times such as Baetidae, which is less susceptible to hydraulic disturbance. A similar finding in Zimbabwe for the Trichoptera order, showed a strong relation between their occurrence and abiotic parameters such as flow velocity and average depth [59].…”

Caddisflies (Trichoptera) as good indicators of environmental stress in mountain lotic ecosystems

“…Removal of tree cover reduces diversity of banks and thus it can increase erosion (Krno et al 2013), which can negatively influence aquatic insects (Chakona et al 2009), because only few species can tolerate it (Ward 1992). Erosion reduces abundance (Wooton et al 1996) and affects feeding types of caddisflies (Gurtz & Wallace 1984;Smith-Cuffney & Wallace 1987).…”

Description of the larva of Oecetis mizrain Malicky & Graf, 2012 (Trichoptera, Leptoceridae) and Lepidostoma scotti (Ulmer, 1930) (Trichoptera, Lepidostomatidae) from Chilimo Forest, Central Ethiopia

“…Caddisfly larvae are widely used as indicator taxa in freshwater assessments as they exploit a wide range of ecological niches, often are found in abundance and cover a wide sensitivity range (Aschalew and Moog 2015;Barbour et al 1999;Chakona et al 2009;Hering et al 2003). Ideally, assessment of the ecological condition of aquatic ecosystems is based on the identification of macroinvertebrates to species-level (Sharma et al 2008).…”