[Effects of ultrasound on the physiological characteristics and competitive growth between and ].

is a common bloom-forming cyanobacterium, which generally coexists and competes with in lakes. Sonication can be used for emergency management of algal blooms. Ultrasound influences algal growth and physiological parameters, as well as interspecific competition in algal community.

Direct versus indirect effects of human activities on dissolved organic matter in highly impacted lakes.

Human activities can alter dissolved organic matter (DOM) in lakes through both direct (i.e., exporting DOM of anthropogenic sources) and indirect effects (i.

[Pollution distribution and potential ecological risk assessment of heavy metals in sediments from the different eastern dredging regions of Lake Taihu].

In order to investigate the distribution characteristics of nutrients and heavy metals in sediments from different eastern dredging regions of Lake Taihu, the surface and core sediment samples at 5 sites (in East Taihu Lake and Xukou Bay) were collected in 2012. Contents of nutrients (TOC, TN and TP) and heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) in the sediments were measured and the pollution degrees of heavy metals were evaluated with the potential ecological risk method. The results showed that the heavy metal contents in Xukou Bay were generally higher than those in East Taihu Lake, whereas the nutrients contents showed the reverse trend.

[Hydroacoustic assessment of fish resources in reservoirs with different fishery management].

By using Biosonics DT-X echosounder (208 kHz), a hydroacoustic investigation was conducted on the fish resources in three mesotrophic reservoirs (Daxi Reservoir, Shahe Reservoir, and Jinniushan Reservoir) with different fishery management in late autumn and early winter 2011, and a GIS model was constructed to assess the fish resource distribution in the reservoirs. No significant difference was observed in the average size of fish in the three reservoirs, but the distribution curves of fish target strength (TS) showed that the fish size distribution proportion was different, and had close correlation with fishery management. The fish density in Daxi Reservoir (averagely 0.

[Experimental study on the environmental fate of nitrogen in snail-macrophyte ecosystem for water purification].

A snail-macrophyte simulation system was built and isotope tracer technique was adopted to study the environmental fate of nitrogen in snail-macrophyte purification system, the results showed that: Vallisneria spiralis increased its wet weight by 580% and its number by 6.6 ramets, moreover, Vallisneria spiralis absorbed 1.07% 15N by the roots and 7.

[Comparison of overwintering and rrecruitment of cyanobacteria in Taihu Lake and Chaohn Lake].

Dynamics of overwintering and recruitment of cyanobacteria were studied in Taihu Lake and Chaohu Lake. The results demonstrated that cyanobacteria sank to the sediment in autumn (November) and recruited to water column in May in Taihu Lake. From November to next May, the cyanobacteria kept growing with an increased growth rate from March to May in the sediment.

[Effects of anthropogenic organic matter inputs on stable carbon and nitrogen isotopes in organisms from microbial food chain in Taihu Lake].

Stable isotope analyses of carbon and nitrogen were used to evaluate autochthonous versus allochthonous contribution to the main microbial food loop components in the four sampling sites based on different trophic status in Taihu Lake. On average, the delta13 C and delta15 N values of organic matter (OM) sources (bacteria, cladocera, particulate and sedimentary organic matter) and the delta13 C of dissolved inorganic carbon (DIC), which are the main components in microbial food chain, showed the lowest values at estuary location compared with the other three sites, reflecting a strong influence by terrestrially derived nutrients and organic matter. The mean delta13 C value of dissolved organic matter (DOM) that we measured was close to the estimated terrestrial delta13 C - 26 per thousandd, suggesting an allochthonous-derived organic C pool.