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The Yangtze River has been a source of life and prosperity for the Chinese people for centuries and is a habitat for a remarkable variety of aquatic species. But the river suffers from huge amounts of urban sewage, agricultural effluents, and industrial wastewater as well as ship navigation wastes along its course. With respect to the vast amounts of water and sediments discharged by the Yangtze River, it is reasonable to ask whether the pollution problem may be solved by simple dilution. This article reviews the past two decades of published research on organic pollutants in the Yangtze River and several adjacent water bodies connected to the main stream, according to a holistic approach. Organic pollutant levels and potential effects of water and sediments on wildlife and humans, measured in vitro, in vivo, and in situ, were critically reviewed. The contamination with organic pollutants, including polycyclic aromatic hydrocarbons, polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans, polybrominated diphenyl ethers (PBDEs), perfluorinated compounds (PFCs), and others, of water and sediment along the river was described. Especially Wuhan section and the Yangtze Estuary exhibited stronger pollution than other sections. Bioassays, displaying predominantly the endpoints mutagenicity and endocrine disruption, applied at sediments, drinking water, and surface water indicated a potential health risk in several areas. Aquatic organisms exhibited detectable concentrations of toxic compounds like PCBs, OCPs, PBDEs, and PFCs. Genotoxic effects could also be assessed in situ in fish. To summarize, it can be stated that dilution reduces the ecotoxicological risk in the Yangtze River, but does not eliminate it. Keeping in mind an approximately 14 times greater water discharge compared to the major European river Rhine, the absolute pollution mass transfer of the Yangtze River is of severe concern for the environmental quality of its estuary and the East China Sea. Based on the review, further research needs have been identified.

Abstract. 1. As mature tropical forests disappear, secondary forests with their potential to conserve mature tropical forest species are increasingly of interest in a conservation context.2. We investigated the recovery of litter inhabiting beetle diversity and composition during natural forest regeneration in the coastal submontane forest of Southern Brazil, using chronosequences on two different soil types: cambisol and gleysol. Secondary forests, ranging in ages from 5 to 50 years, as well as old-growth forests were studied. Beetles were sifted from leaf litter and extracted using the Winkler technique.3. Young secondary forests had a very low species density and a significantly different and heterogeneous species composition compared to old-growth forests. During forest regeneration, species density greatly increased and the species composition of older secondary forests was similar to that of old-growth forests. The recovery pattern of species density and composition differed between soil types; nonetheless, they showed the same tendencies generally. Thus, mature secondary forests of about 35-50 years can be assumed to contribute substantially to the maintenance of forest beetle species.4. Litter quantity was not only significantly correlated with species density; but, even reflected the density pattern of both soil types. Thus, litter quantity is an important factor for maintaining or recovering high beetle densities. The composition of beetle assemblages was strongly affected by soil type. Thus, soil type should be considered in regional biodiversity monitoring and conservation actions.

Bioassays are particularly useful tools to link the chemical and ecological assessments in water quality monitoring. Different methods cover a broad range of toxicity mechanisms in diverse organisms, and account for risks posed by non-target compounds and mixtures. Many tests are already applied in chemical and waste assessments, and stakeholders from the science-police interface have recommended their integration in regulatory water quality monitoring. Still, there is a need to address bioassay suitability to evaluate water samples containing emerging pollutants, which are a current priority in water quality monitoring. The presented interlaboratory study (ILS) verified whether a battery of miniaturized bioassays, conducted in 11 different laboratories following their own protocols, would produce comparable results when applied to evaluate blinded samples consisting of a pristine water extract spiked with four emerging pollutants as single chemicals or mixtures, i.e. triclosan, acridine, 17α-ethinylestradiol (EE2) and 3-nitrobenzanthrone (3-NBA). Assays evaluated effects on aquatic organisms from three different trophic levels (algae, daphnids, zebrafish embryos) and mechanism-specific effects using in vitro estrogenicity (ER-Luc, YES) and mutagenicity (Ames fluctuation) assays. The test battery presented complementary sensitivity and specificity to evaluate the different blinded water extract spikes. Aquatic organisms differed in terms of sensitivity to triclosan (algae > daphnids > fish) and acridine (fish > daphnids > algae) spikes, confirming the complementary role of the three taxa for water quality assessment. Estrogenicity and mutagenicity assays identified with high precision the respective mechanism-specific effects of spikes even when non-specific toxicity occurred in mixture. For estrogenicity, although differences were observed between assays and models, EE2 spike relative induction EC values were comparable to the literature, and E2/EE2 equivalency factors reliably reflected the sample content. In the Ames, strong revertant induction occurred following 3-NBA spike incubation with the TA98 strain, which was of lower magnitude after metabolic transformation and when compared to TA100. Differences in experimental protocols, model organisms, and data analysis can be sources of variation, indicating that respective harmonized standard procedures should be followed when implementing bioassays in water monitoring. Together with other ongoing activities for the validation of a basic bioassay battery, the present study is an important step towards the implementation of bioanalytical monitoring tools in water quality assessment and monitoring.

Abstract-A sediment contact test (SCT) battery consisting of five ecotoxicological test systems was applied to 21 native freshwater sediments characterized by a broad variety of geochemical properties and anthropogenic contamination. Higher plants (Myriophyllum aquaticum), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), zebrafish embryos (Danio rerio), and bacteria (Arthrobacter globiformis), representing various trophic levels and exposure pathways, were used as test organisms. The test battery detected sediment toxicity caused by anthropogenic pollution, whereas the various tests provided site-specific, nonredundant information to the overall toxicity assessment. Based on the toxicity pattern derived from the test battery, the sediments were classified according to a newly proposed classification system for sediment toxicity assessment. The SCT-derived classification generally agreed well with the application of consensus-based sediment quality guidelines (SQGs), especially with regard to sediments with high toxic potential. For sediments with low to medium toxic potential, the SQGs often underestimated the toxicity that was detected by the SCTs, underpinning the need for toxicity tests in sediment quality assessment. Environ. Toxicol. Chem. 2013;32:144-155. # 2012 SETAC

Green infrastructure in cities is considered to serve as a refuge for insect pollinators, especially in the light of an ongoing global decline of insects in agricultural landscapes. The design and maintenance of urban green spaces as key components of green infrastructure play a crucial role in case of nesting opportunities and for foraging insects. However, only few research has explored the impact of urban green space design on flower visitor communities, plant-pollinator interaction and the provision of the ecosystem service of pollination in cities. We investigated the abundance and diversity of pollinator communities in different urban park types in designed, standardized vegetation units, linked the visitation rates to the structural composition of the park types and derived indices for implemented pollination performances. The study was performed in two different structural park elements, flower beds and insect-pollinating trees. To gain a comprehensive understanding of the interaction between plants and pollinators, we calculated a plant-pollinator network of the recorded community in the investigation area. Visitation rates at different park types clearly showed, that the urban community gardens in comparison to other urban park types had a significantly higher abundance of pollinator groups, comparable to results found on a rural reference site. Tilia trees contributed significantly to the ecosystem service of pollination in investigated green spaces with a high supply of nectar and pollen during their flowering period. Calculations of pollination performances showed that recreational parks had comparably low visitation rates of pollinators and a high potential to improve conditions for the ecosystem service of pollination. The results indicated the strong potential of cities to provide a habitat for different groups of pollinators. In order to access this refuge, it is necessary to rely on near-natural concepts in design and maintenance, to create a wide range of flower diversity and to use even small green patches. Based on the findings, we encourage an integrated management of urban free spaces to consider parks as key habitats for pollinators in anthropogenic dominated, urban environments.

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