Spatial and temporal patterns of fish assemblages in mountain streams of
the Ren River, southwest China
Abstract
The spatial-temporal patterns of fish assemblages in lotic systems can
provide useful information in developing effective conservation
measures. This study aimed to explore the spatiotemporal changes in fish
assemblage and their association with environmental factors in mountain
streams of Ren River, southwest China. Filed investigations were
conducted at 18 sites during rainy and dry season in 2017. A total of 21
species, belonged to 3 orders, 8 families and 19 genera, were collected.
Analysis of similarities (ANOSIM) showed fish assemblages structure
varied significantly at the spatial scale, but not at the temporal
scale. In low order sites, fish assemblages were mainly dominated by
cold water and rheophilic species (e.g. Rhynchocypris oxycephalus,
Scaphesthes macrolepis, Metahomaloptera omeiensis and Gnathopogon
herzensteini), while those in high order sites were predominated by warm
water and eurytopicity or stagnophilic species (e.g. Squalidus
argentatus, Hemiculter leucisculus and Zacco platypus). Canonical
correspondence analysis (CCA) showed fish assemblages were structured by
a combination of large-scale landscape factors (e.g. altitude and
C-link) and small-scale habitat features (e.g. channel width, water
temperature and depth). Among these factors, landscape factors had the
greatest influence on fish assemblage, while local habitat measures
played less important roles or just acted in certain season.