About 114 "species" of Macrothrichidae, Eurycercidae, and Chydoridae (Cladocera, Anomopoda), belonging to 39 genera, have been reported from China, with 14 species in 6 genera in Macrothrichidae, 2 species in one genus in Eurycercidae, and 98 species in 31 genera in Chydoridae. In total, 203 species in 62 genera, 13 families and 4 orders have so far been reported from the country. Of these, 187 are tentatively considered as valid, while 16 are incertae sedis. In reality, many records hide taxonomic problems that remain to be settled. Up to 10 percent of this fauna might be endemic at the species level, but we expect this number to increase pending new, comprehensive studies. No endemic genera fall to be recorded. Most of the several hundreds of taxonomic or biogeeographic papers from which this information was extracted suffer from poor or outdated taxonomy, such that up to half of all species are up for re-evaluation. Detailed morphological examination, but also provoked male production, especially in chydorids, are ways to improve identifications and should be stimulated. On the other hand, the inventory is certainly still incomplete with several tropical-subtropical taxa still to be expected in China. The extreme south and islands are among promising sites that remain to be explored, as well as extreme habitats all over the country. Molecular studies in China started around the beginning or the present decade, and should be multiplied.

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Rapid climate changes may potentially have strong impacts on the ecosystem structure and nutrient dynamics of lakes as well as implications for water quality. We used a space-for-time approach to elucidate such possible effects by comparing data from 1656 shallow lakes (mean depth <3 m) in north temperate Denmark (DK) and subtropical Florida (FL). The lakes were categorized into 7 total phosphorus (TP) classes within the range of 2 to 300 µg L −1. Physicochemical variables showed significant seasonal differences, which can be attributed to different sunlight regimes and temperatures. The FL lakes had overall higher fish biomasses (notably in the littoral zone) but a substantially lower zooplankton biomass and body mass of microcrustaceans, a much lower zooplankton:phytoplankton biomass ratio (lower grazing on phytoplankton), and a markedly lower biomass of benthic invertebrates, indicating much greater control of consumers by fish in the FL lakes. Accordingly, the summer phytoplankton biomass was higher in the FL lakes. Cyanobacteria in summer were proportionally more important in the FL lakes at all TP levels, whereas the proportion of dinophytes, chrysophytes, and cryptophytes was higher in the DK lakes at low TP. Submerged macrophytes occurred at higher TP (>100 µg L −1) in the FL lakes, but coverage was higher in the DK lakes at low TP. We also found lower oxygen saturation in the nutrient-rich FL lakes than in the DK lakes, suggesting lower net ecosystem production in the FL lakes. We discuss our results within the framework of climate warming.

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Approximately 199 cladoceran species, 5 marine and 194 freshwater and continental saltwater species, live in China. Of these, 89 species are discussed in this paper. They belong to the 4 cladoceran orders, 10 families and 23 genera. There are 2 species in Leptodoridae; 6 species in 4 genera and 3 families in order Onychopoda; 18 species in 7 genera and 2 families in order Ctenopoda; and 63 species in 11 genera and 4 families in non-Radopoda Anomopoda. Five species might be endemic of China and three of Asia. Many records are suspect at the species level, and numerous taxonomic problems remain to be settled.

We quantified recovery of plankton in a large subtropical shallow lake from the catastrophic impacts of three successive major hurricanes. This assessment was possible because hurricanes passed directly over the lake amid an ongoing long‐term sampling programme that included nearly all components of the plankton, from bacteria to crustacean zooplankton. We compared attributes of plankton 5 years after the hurricanes to a pre‐hurricane period and to a period immediately after the storms. We evaluated both community‐level properties (biomass, biomass ratios, diversity, and dominance of major plankton groups) and species‐level properties (species absolute and relative biomass) at four sites in the lake representing different ecological zones. The hurricanes strongly affected water quality and plankton community structure. The lake experienced a regime shift, losing its submerged aquatic vegetation and becoming homogenous and turbid at all sampled sites. Five years after the storms, chemical and physical conditions recovered across the lake, with a few exceptions. Between 35 and 93 plankton species were lost at the sampling sites, with greatest losses in the phytoplankton. Relative species biomass displayed substantive changes too. Daphnia ambigua did not recover at three of the sites, Polyarthra vulgaris greatly increased lake‐wide, and at a central pelagic site, there was a total loss of heterotrophic nano‐flagellates and a much higher biomass of diatoms than before the hurricanes, despite recovery of irradiance, depth, nutrient levels and other attributes. Most community‐level properties were resilient, returning to pre‐hurricane conditions of total biomass, ratios of autotrophs to heterotrophs and ratios of protozoa to metazoa. This likely happened because of species compensation in the biodiverse community. The exception was at a central pelagic site, where the community‐level properties did not recover and nearly 50 per cent of species were lost. The community resilience, despite a regime shift, may have occurred because of a controlled lowering of water levels in the lake for flood protection, which led to regrowth of lost submerged aquatic vegetation (SAV) and migration of mud sediments back towards mid‐lake. In this lake and others with a history of high nutrient inputs, shallow depth and flocculent sediments, resilience may be low unless counter‐acting forces are able to push the system back after a regime shift.

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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.