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During 2010 to 2012, fish diversity in Qingcaosha Reservoir was studied based on gillnets (multi-mesh monofilament gillnets and single-mesh trammel gillnets), electric fishing, bottom trawl and cage. The investigation collected a total of 34 fish species, belonging to 8 orders, 12 families. Cypriniformes contained the largest number of species (19 species) in the collection, followed by Perciformes (6 species). Multi-mesh monofilament gillnets sampled 19 fish species, of which Coilia nasus was the dominant species. Hierarchical cluster analysis indicated that mesh size of monofilament gillnets had significant influence on the composition of catches: C. nasus and Hemiculter bleekeri were the dominant species of catches of gillnet netting with mesh size of 2 cm, while C. nasus was the dominant species of catches of the nettings with mesh sizes larger than 2 cm. Species numbers and the catch per unit of effort (CPUE) had a decreasing tendency with the increasing mesh size. Mesh size also had significant effects on the total length distribution of the dominant species C. nasus, which increased with the increasing mesh size. The results suggested that a combination of several gears was required to reliably estimate fish diversity of standing waters. [ABSTRACT FROM AUTHOR]

Coastal marshes have a significant capacity to sequester carbon; however, sea-level rise (SLR) is expected to result in prolonged flooding and saltwater intrusion in coastal regions. To explore the effects of SLR projections on net CO 2 uptake in coastal marshes, we conducted a "double-check" investigation, including the eddy covariance (EC) measurements of the CO 2 fluxes in subtropical coastal marshes along inundation and salinity gradients, in combination with a mesocosm experiment for analyzing CO 2 flux components under waterlogging and increased salinity conditions. During the same measurement periods, the net ecosystem CO 2 exchange (NEE EC based on the EC dataset) in an oligohaline marsh was higher than that in a low-elevation mesohaline marsh, whereas the NEE EC was lower than that in a high-elevation freshwater marsh. The declines in NEE EC between the marshes could be attributed to a greater decrease in gross primary production relative to ecosystem respiration. Waterlogging slightly increased the NEE ms (NEE based on the mesocosms) because of inhibited soil respiration and slight changes in plant photosynthesis and shoot respiration. However, the NEE ms measured during the drainage period decreased significantly due to the stimulated soil respiration. The NEE ms decreased with increasing salinity (except under mild salinity), and waterlogging exacerbated the adverse impacts of salinity. The amplificatory effect of decreases in both leaf photosynthesis and growth under hydrological stresses contributed more to reduce the NEE ms than to respiratory effluxes. Both waterlogging and increased salinity reduced the root biomass, soil microbial biomass, and activities of assayed soil enzymes (except for cellulase under waterlogging conditions), leading to limited soil respiration. The declines in plant growth, photosynthesis, and soil respiration could also be attributed to the decrease in soil nutrients under waterlogging and increased salinity conditions. We propose that the coupling of SLR-driven hydrological effects lowers the capacity of CO 2 uptake in subtropical coastal marshes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

During 2010 to 2012, fish diversity in Qingcaosha Reservoir was studied based on gillnets (multi-mesh monofilament gillnets and single-mesh trammel gillnets), electric fishing, bottom trawl and cage. The investigation collected a total of 34 fish species, belonging to 8 orders, 12 families. Cypriniformes contained the largest number of species (19 species) in the collection, followed by Perciformes (6 species). Multi-mesh monofilament gillnets sampled 19 fish species, of which Coilia nasus was the dominant species. Hierarchical cluster analysis indicated that mesh size of monofilament gillnets had significant influence on the composition of catches: C. nasus and Hemiculter bleekeri were the dominant species of catches of gillnet netting with mesh size of 2 cm, while C. nasus was the dominant species of catches of the nettings with mesh sizes larger than 2 cm. Species numbers and the catch per unit of effort ( CPUE) had a decreasing tendency with the increasing mesh size. Mesh size also had significant effects on the total length distribution of the dominant species C. nasus, which increased with the increasing mesh size. The results suggested that a combination of several gears was required to reliably estimate fish diversity of standing waters.