In order to understand the impacts of the reservoir construction on the diversity and ecological network of different microbial communities, seven sampling sites were set up in the Hengshan Reservoir in 2021. Water samples were collected from the surface and bottom of the reservoir. After filtering and extracting total DNA samples, high-throughput sequencing was carried out based on 16S and 18S rDNA to investigate the response of community structure, molecular ecological network, and keystone species of different microbial groups to water environment changes.
View Article and Find Full Text PDFPlanktonic microeukaryotes are usually composed of a few abundant species and a large number of rare species, which play an important role in maintaining the health and stability of aquatic ecosystems. At present, little is known about the biogeographical distribution patterns of these two groups of microeukaryotes in large damming rivers. This study analyzed the distribution patterns of abundant and rare planktonic microeukaryotes and the dominant factors affecting their spatial distributions in the Jinsha River, one of the largest rivers in southwestern China that is strongly regulated by cascade dams.
View Article and Find Full Text PDFFor the sake of investigating the effects of residual antibiotics in soil on plant growth, sulfamethazine, which is commonly detected in soil, was selected in this project. In general, the growth index of rice at the seedling and mature stages, physiological/biochemical characteristics of roots and leaves, antibiotic residues, enrichment factors, and transport coefficients in various rice organs were respectively tested and analyzed to evaluate the ecological effects of sulfamethazine residues on rice. The results revealed that the inhibitory effect of sulfamethazine on plant height and biomass was maintained during the whole growth cycle.
View Article and Find Full Text PDFEukaryotic microbial communities play an important role in biogeochemical cycling and maintaining the health and stability of ecosystems. However, little is known about the geographical distribution patterns, key driving mechanisms, and interspecific interactions of eukaryotic microorganisms in large rivers. This study investigated the geographical distribution characteristics, influencing factors, and interspecific interactions of eukaryotic microorganisms in sediments from the Jinsha River, a cascade hydropower development river in southwest China.
View Article and Find Full Text PDFCoral reefs thrive and provide maximal ecosystem services when they support a multi-level trophic structure and grow in favorable water quality conditions that include high light levels, rapid water flow, and low nutrient levels. Poor water quality and other anthropogenic stressors have caused coral mortality in recent decades, leading to trophic downgrading and the loss of biological complexity on many reefs. Solutions to reverse the causes of trophic downgrading remain elusive, in part because efforts to restore reefs are often attempted in the same diminished conditions that caused coral mortality in the first place.
View Article and Find Full Text PDFIn this study, four typical submerged macrophytes, namely , , , and , were tested for their chlorophyll content and antioxidant enzyme activity, to analyze their cadmium tolerance. The biota-sediment accumulation factor (BSAF) and plant transport factor (TF) were utilized to understand the accumulation capacity of the plants. Finally, the distribution of cadmium in submerged macrophytes was revealed through phytohistochemical methods, to provide theoretical support for the practical application of submerged macrophytes.
View Article and Find Full Text PDFHuan Jing Ke Xue
December 2020
As an important primary producer, diatoms play a key role in aquatic ecosystems. However, little is known about the geographical distribution characteristics and driving factors of diatoms in large rivers. In this study, based on a high-throughput sequencing dataset of microeukaryotes, we analyzed the diversities and community compositions of planktonic and sedimentary diatoms in the 1200 km mainstream of Lancang River, a typical large river in southwestern China.
View Article and Find Full Text PDFMetal release rates were measured from four different copper alloy-based materials used by the aquaculture industry: copper sheet machined into a diamond mesh, copper alloy mesh (CAM), silicon bronze welded wire mesh, and copper sheeting, and compared with conventional nylon aquaculture net treated with a cuprous oxide antifouling (AF) coating. Release rates were measured in San Diego Bay using a Navy-developed Dome enclosure system at nine different time points over one year. As expected, copper was the predominant metal released, followed by zinc and nickel, which were fractional components of the materials tested.
View Article and Find Full Text PDFTo study the pollution characteristics and ecological risks of heavy metals in the western area of the Wangyu River, water and surface sediment samples of five rivers were investigated. The concentration and chemical fractions of eight heavy metals (Ni, Cu, Cr, Zn, As, Cd, Pb, and Hg) were analyzed, the pollution sources of heavy metals were studied using multivariate statistical analysis, and various ecological risk assessments were applied to identify the level of heavy metal contaminants. The results showed that the concentration of heavy metals in water was low, except for Hg, which was lower than the Class I standard of Surface Water Environmental Quality Standard.
View Article and Find Full Text PDFWhile wastewater and polybrominated diphenyl ethers (PBDEs) are commonly both discharged into aquatic ecosystems, little information is known about how wastewaters with different nutrient levels impact on microbial degradation of PBDEs. In this study, we used an anaerobic microcosm experiment to examine how the removal rates of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) from contaminated sediment varied when exposed to three wastewaters with different nutrient properties, namely livestock wastewater (LS), municipal sewage (MS), and shrimp pond wastewater (SP), and to determine the microbial controls on removal processes. We found that BDE-47 degraded relatively rapidly in MS, which had low carbon and nitrogen concentrations, but degraded much more slowly in LS and SP, which had relatively high nutrient concentrations.
View Article and Find Full Text PDFWhile nitrogen (N) fixation and ammonia oxidation by microorganisms are two important N cycling processes, little is known about how the microbes that drive these two processes respond when sediments are contaminated with persistent organic pollutants. In this study, we carried out a laboratory microcosm experiment to examine the effects of decabromodiphenyl ether (BDE-209), either on its own or combined with a common mangrove species, Avicennia marina, on the abundance, diversity, and community composition of N-fixing bacteria (NFB) and ammonia-oxidizing archaea (AOA) and bacteria (AOB) in mangrove sediments. The sediments were very N-limited after one year.
View Article and Find Full Text PDFIt is acknowledged that organohalide-respiring bacteria (OHRB) can degrade polybrominated diphenyl ethers (PBDEs); however, very little is known about the distribution of OHRB or their response to PBDE contamination in natural sediments. We collected sediments from 28 sampling sites in Taihu Lake, China, and investigated the spatial distribution and diversity of OHRB, and the relationships between the PBDE contamination levels and the PBDE removal potential. The abundances of five typical OHRB genera, namely Dehalobacter, Dehalococcoides, Dehalogenimonas, Desulfitobacterium, and Geobacter, ranged from 0.
View Article and Find Full Text PDFInt J Environ Res Public Health
March 2017
Yixing, known as the "City of Ceramics", is facing a new dilemma: a raw material crisis. Cadmium (Cd) exists in extremely high concentrations in soil due to the considerable input of industrial wastewater into the soil ecosystem. The in situ technique of diffusive gradients in thin film (DGT), the ex situ static equilibrium approach (HAc, EDTA and CaCl2), and the dissolved concentration in soil solution, as well as microwave digestion, were applied to predict the Cd bioavailability of soil, aiming to provide a robust and accurate method for Cd bioavailability evaluation in Yixing.
View Article and Find Full Text PDFThe present study aimed to investigate the effects of on morphine tolerance through the targeting of CXC chemokine receptor-4 (CXCR4) in a rat model of bone cancer pain (BCP). Sprague-Dawley (SD) rats were obtained and divided into model saline (=10), model morphine (=50), normal saline (=10) and normal morphine (healthy rats, =10) groups. After BCP rat model establishment, the remaining SD rats (=40) in the model saline group were assigned into pLV-THM-, pLV-THM-anti-, CXCR4 shRNA, blank and PBS groups.
View Article and Find Full Text PDFOrganic amendments have been proposed as a means of remediation for Cd-contaminated soils. However, understanding the inhibitory effects of organic materials on metal immobilization requires further research. In this study colza cake, a typical organic amendment material, was investigated in order to elucidate the ability of this material to reduce toxicity of Cd-contaminated soil.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
May 2016
Stormwater runoff is generally characterized as non-point source pollution. In the present study, antibiotic concentration and antibiotic susceptibilities of cultivable heterotrophic bacteria were investigated in two small shallow urban lakes before and after strong storm event. Several antibiotics, lactose-fermenting bacteria and cultivable heterotrophic bacteria concentrations increased in surface water and/or surface sediment of two small urban lakes (Lake Xuanwu and Wulongtan) after strong storm event.
View Article and Find Full Text PDFOrganic amendments have been widely proposed as a remediation technology for metal-contaminated soils, but there exist controversial results on their effectiveness. In this study, the effect of pig manure addition on cadmium (Cd) bioavailability in Cd-contaminated soils was systematically evaluated by one dynamic, in situ technique of diffusive gradients in thin films (DGT) and four traditional methods based on the equilibrium theory (soil solution concentration and the three commonly used extractants, i.e.
View Article and Find Full Text PDFIn order to determine the effects of nutrient inputs on changes of phosphorus forms and phytoplankton growth in large shallow lakes, an enrichment bioassay was conducted using surface lake water collected from the Meiliang Bay of Taihu Lake in spring. The concentration of different phosphorus forms, phytoplankton biomass (chlorophyll a) and alkaline phosphatase activity (APA) was analyzed after the addition of different concentrations of inorganic nutrients. The results showed that the phytoplankton biomass increased significantly with the addition of phosphorus (P), but with no primary effect from nitrogen (N), which suggested the phytoplankton growth was mainly limited by P.
View Article and Find Full Text PDFThe rapid development of antibiotic-resistant bacteria (ARB) has been of concern worldwide. In this study, antibiotic resistance genes (ARGs) were investigated in antibiotic-resistant Escherichia coli isolated from surface water samples (rivers, n = 17; Taihu Lake, n = 16) and from human, chicken, swine, and Egretta garzetta sources in the Taihu Basin. E.
View Article and Find Full Text PDFThe likely protective effects of nitric oxide (NO) against ammonium toxicity were investigated in the submerged macrophyte Hydrilla verticillata. The plants were subjected to ammonium stress (3mM ammonium chloride) in the presence of sodium nitroprusside (SNP, 10 μM), an NO donor. Treatment with SNP significantly increased the NO content and partially reversed the ammonium-induced negative effects, including membrane damage and the decrease in levels of chlorophyll, malondialdehyde, glutathione and ascorbic acid.
View Article and Find Full Text PDFEcotoxicol Environ Saf
February 2010
To investigate ammonium toxicity, the submerged plant Hydrilla verticillata (L.f.) Royle was treated with 0.
View Article and Find Full Text PDFTo investigate the effects of zinc (Zn) on aquatic macrophyte, the submerged plant Hydrilla verticillata (L.f.) Royle was cultured in control solution or together with 0.
View Article and Find Full Text PDFZinc (Zn) is a necessary element for plants, but excess Zn can be detrimental. To investigate Zn toxicity, rapeseed (Brassica napus) seedlings were treated with 0.07-1.
View Article and Find Full Text PDFThe fractions of phosphorus (P) and Fe in the surface sediments of three typical urban shallow lakes (Xuanwu Lake, Daming Lake and Mouchou Lake) were determined using improved methods of SEDEX and BCR, respectively, and the relationship between P and Fe in sediments was also analyzed. P analyses showed that the relative lower content of Al-P was found in sediments of three urban lakes, while the percentage of Fe-P was in the range of 17.10%-27.
View Article and Find Full Text PDFTo investigate the potential bioavailability and mobility of phosphorus (P) in sewage sludge, the Standards, Measurements and Testing (SMT) programme was employed to characterize the distribution of P in sewage sludge from different treatment stage of Jiangxinzhou WWTP. The results showed that the inorganic phosphorus (IP), accounting for 61%, was the predominant fraction of total phosphorus (TP), while the organic phosphorus (OP) in TP was only 15% to 35%. And the IP mainly distributed in the non-apatite inorganic phosphorus (NAIP) fraction, accounting for more than 60%.
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