We investigated abundance and distribution characteristics of five little understood groups of picophytoplankton in the Pearl River Estuary. It was suggested that Prochlorococcus density and distribution range were balanced by river discharge and saline–water intrusion. The present study showed that low river input resulting from extreme drought events exerted less negative pressure on picophytoplankton abundance.

Reference condition and historical variability of aquatic ecosystems are key features of wetland systems. Based on diatom records from 10 Yangtze lakes, this study defined their ecological and chemical reference conditions, the historical variability and its controlling factors. This study demonstrates the robustness of palaeolimnological techniques in reconstructing the historical ecological characters of lake ecosystems, which may provide essential information for the management of wider types of wetland.

Our study revealed the variability in groundwater attributes and their impacts on vegetation succession in the lower Heihe River Basin, north-western China, where groundwater heterogeneity had an important impact on vegetation succession, and thus showed a prevalence of groundwater attributes-based niche differentiation among plant communities. Our study provides a scientific basis for the understanding of ecosystem restoration in similar regions.

This is the first in situ seasonal study to investigate how freshwater autotrophic picoplankton responses to CO₂ changes. CO₂ elevation could significantly increase the abundance of photosynthetic picoeukaryotes in all seasons except winter, but did not have any influence on picocyanobacterial abundance. This might cause a reduction of the transfer of matter and energy to higher trophic levels and an increase the importance of the microbial food web under high CO₂ levels.

Phosphorus is vulnerable to the artificial lake, and sensitive to aquatic ecosystems. Phosphorus dynamics in a huge reservoir should be well documented, and the Three Gorges Reservoir exerts important influence on phosphorus speciation and transport. This study will improve our understanding of the mechanisms and processes responsible for the effect of artificial lake with a unique gradual mode of impoundment.

In order to learn the relationship between the non-indigenous Japanese smelt and the collapse of the native perch population, we investigated the diet of Japanese smelt in Lake Ulungur, China. Cladocerans were the most important food; rotifers, copepods, surface food and chironomid larvae, substituted when cladocerans were scarcer. Seasonal predation by Japanese smelt might influence the collapse of the perch population.