Planktonic Rotifers in a Subtropical Shallow Lake: Succession, Relationship to Environmental Factors, and Use as Bioindicators

Abstract

Changes in the density and species composition of planktonic rotifers as well as their relationship to several environmental variables were studied at Dadian Lake, a shallow subtropical lake, which was completely dredged and reconstructed. Samples were taken monthly (2006–2009) at five stations. The total rotifer abundance exponentially declined and reached a relatively stable stage in 2009. Polyarthra dolichoptera and Trichocerca pusilla dominated the rotifer community in most seasons. TN, TP, and CODMn went down at the beginning of the monitoring period, rebounded in the second winter, and then decreased and reached a stable state in 2009. CCA showed that the most significant variations were caused by fluctuations in temperature, CODMn, SRP, and NO2-N. The rotifer community experienced a two-stage succession and the difference of species between the stages was exhibited during warm seasons. GAMs indicated that the selected factors were responsible for 64.8% of the total rotifer abundance variance and 16.5~64.3% of the variances of individual species abundance. Most of the environmental parameters had effects on rotifer abundance that could only be described by complicated curves, characterised by unimodality and bimodality instead of linearity. Our study highlighted the temperature influence on rotifer species composition and total abundance in subtropical lakes.

Behavioural response ofBrachionus calyciflorusto the predatorAsplanchna sieboldii

“…Before exposure, both Asplanchna ‐conditioned medium and non‐predator medium were filtered through glass fibre filters (0.45 µm). Both the prey density (1,000 ind./L) and the predator concentrations (80 ind./L) in the present work are relatively high, but this is common in natural waters (Halbach, 1970; Ji et al., 2013; Iyer & Rao, 1996; Oltra et al., 2001). The experiment was started by placing 30 egg‐bearing amictic B .…”

Key drivers structuring rotifer communities in ponds: insights into an agricultural landscape

“…Previous findings in one of our studied ponds indicate that nutrients made available via mineralization and phytoplankton basal metabolism were not sufficient to cover phytoplankton P and N requirements, pointing to a limited contribution of phytoplankton to internal nutrient recycling; and a substantial proportion of the bioavailable nutrient concentrations in ponds might originate from submerged macrophyte decomposition and nutrient release from sediments ( Onandia et al ., 2018 ). It is known that nutrients can influence the abundance and richness of rotifers via trophic cascades ( Ji et al ., 2013 ). However, no significant correlation of this component with rotifer abundance or rotifer diversity estimates was found.…”

A review of potential methods for zooplankton control in wastewater treatment High Rate Algal Ponds and algal production raceways

“…Movement within habitats occurs by floating, drifting or swimming [43]. Species composition within habitats is influenced by local climate, diurnal cycles, water quality, trophic state, pH, direct predation, competition among zooplankton for shared food, competition through mechanical interference, crowding, food composition and size, and physiological modifications induced by infochemicals [48][49][50][51][52][53][54][55][56][57][58]. Moreover, microalgal species and abundance are directly controlled by zooplankton, resulting in complex mutual interactions [59][60][61].…”