Notes

Perioperative Coagulation Monitoring.
The amendment of POM also stimulated the activity of organic matter metabolic enzymes, promoting microbial activity. Moreover, 16S rRNA gene sequencing suggested that the mineralization of NOM (especially POM) increased the diversity of the microbial community, favored the survival of Proteobacteria and Bacteroidetes, and upregulated the function genes of organic matter metabolism. These results suggest that the composition and function of microbial community in sediments were associated with the origin, composition, and concentration of NOM input.In this study, 23 typical sampling points were selected from the Harbin urban river network during the wet season from June to August in 2019, including the Harbin section of the Songhua, Hejiagou, Majiagou, and Ashi rivers to study the distribution of phytoplankton communities. Characteristics and driving factors influencing the water environment were determined, and a total of 174 taxa of phytoplankton were identified. During the wet period from June to August, the composition of the phytoplankton community in the urban river network of Harbin was dominated by Diatom and Chlorophyta, which gradually shifted toward Diatom and Cyanophyta. The dominant species mainly includeCyclotella meneghiniana Kützing, Nitzschia palea (Kützing) W.Smith, Synedra ulna (Nitzsch) Ehrenberg, Ankistrodesmus angustus Bernard, Pseudanabaena limnetica (Lemmermann) Komárek, and Cryptomonas ovata Ehrenberg. One-way crossed similarity analysis (One-way crossed ANOSIM) revealed significant differences in phytoplankton composition among different sections of the river during the study period (P less then 0.05). The Harbin section of the Songhua River was richer in phytoplankton than other sections. Redundancy analysis (RDA) shows that TP and pH are the main environmental factors that cause differences in the structure of the phytoplankton community in each section of the Harbin urban river network. This research aims to enrich the research on the ecological evaluation of urban river network by studying the phytoplankton community and environmental relevance of Harbin urban river network and provide a theoretical basis for future urban river network ecological monitoring, management, and restoration.Changes in the community stability of freshwater phytoplankton not only induce a series of ecological environment problems but also influence freshwater ecosystem service functions. To understand the changes in community stability and its driving factors, phytoplankton and environmental parameters were analyzed at 11 sample sites in Huaxi River, a tributary of the Three Gorges Reservoir, in spring, summer, autumn, and winter. Moreover, the resource use efficiency (RUEPP), phytoplankton richness (S), phytoplankton evenness (J), and community turnover (BC) were also determined. Results showed that a total of 8 phyla, including 103 genera and 380 species, were identified in Huaxi River throughout the year. Among them, 264 species were collected in spring, 181 in summer, 197 in autumn, and 183 in winter. The number of Chlorophyta was the largest, followed by Bacillariophyta, Euglenophyta, and Cyanophyta. The number of species and cell density in S0 site were the smallest, while those in S2 site were the largest. The RUEPP was fluctuated in four seasons, with the maximum in summer and the minimum in autumn. BC was significantly negatively correlated with RUEPP, phytoplankton richness, total phosphorus (TP), orthophosphate (PO43--P), total nitrogen (TN), nitrate (NO3--N), permanganate index, and conductivity (Spc); however, it was significantly positively correlated with phytoplankton evenness and dissolved oxygen (DO). These results suggest that water level regulation in the Three Gorges Reservoir has a significant impact on the structure of phytoplankton community in Huaxi River, which leads to the instability of phytoplankton community and easy replacement, and the degree of community turnover is affected by the combined effect of biological and abiotic factors.To increase crops yields, applying large amounts of fertilizers has become increasingly common in agricultural regions, resulting in NO3--N groundwater pollution. Agricultural non-point pollution is the main source of groundwater NO3--N pollution. To ensure drinking water safety and quality, it is crucial to clarify the sources of NO3--N pollution in agricultural regions. In this study, 35 sampling sites were randomly selected in the Qingdao agricultural area in 2009 and 2019. The spatial distribution of NO3--N concentration was analyzed by the inverse distance weighting method (IDW). The nitrogen and oxygen isotopes were used as a tool to trace sources of NO3--N and the SIAR model was used to quantify contribution proportion of pollution sources. The results showed that the concentration of NO3--N (average) in groundwater in Qingdao has been reduced from 38.49 mg·L-1 in 2009 to 22.37 mg·L-1 in 2019, but it is still higher than the maximum allowable concentration of NO3--N in drinking water set by the World Health Organization (WHO). The NO3--N concentration gradually increased from south to north both in 2009 and 2019. The cross diagram of δ15N-NO3- and δ18O-NO3- show that the main sources of NO3--N in groundwater in Qingdao are chemical fertilizers, soil nitrogen, and manure and sewage. BIX 01294 mw Water isotopes indicate that precipitation was the main source of groundwater in Qingdao. The SIAR model results indicated that the contribution of each source ranked as followsmanure and sewage (47.42%) > soil nitrogen (27.80%) > chemical fertilizer (14.32%) > atmospheric nitrogen depositions (10.43%). From 2009 to 2019, the quality of groundwater in Qingdao has been improved, but NO3--N pollution still cannot be ignored. According to the results, prevention and control should be made to ensure the safety of drinking water and the sustainable development of agriculture.The interface between Shengjin Lake and Yangtze River was selected as the study area. The water chemical composition and hydrogen and oxygen isotope values of different types of water bodies were tested, and their seasonal variation characteristics were analyzed to explore the sources of chemical ions in the surface and groundwater. Finally, the contribution of mixed water sources to chemical ions in groundwater was estimated. The results show the following ① The concentration of chemical ions in the surface and groundwater of the study area is higher than that of atmospheric precipitation, and the physical and chemical parameters exhibit seasonal variation. ② Surface water mainly belongs to the Ca-HCO3 type, but the proportion of the Ca-SO4 type in summer is significantly lower than that in other seasons; Groundwater primarily belongs to Ca-HCO3 and Ca-SO4 types, with proportions of 46% and 27%, respectively, and the seasonal difference is not significant. ③ Ca2+ and Mg2+ in the surface and groundwater mainly come from the dissolution of carbonate rocks, carbonic acid and sulfate ions participate in the dissolving process of carbonate minerals.
Website: https://www.selleckchem.com/products/bix-01294.html