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Cretaceous aeolian deposition is important for understanding variations of the tropical--subtropical atmospheric circulation under the greenhouse background. Nevertheless, detailed records revealing the response of aeolian deposition to rising atmospheric CO2 are still lacking. To shed light on their linkage, we examined the Early Cretaceous stratigraphic evolution of the Hekou Group in the Baiyin-Jingyuan Basin, northern China, using multiple methods. The results indicate that the lower Hekou Group is characterized by a transition from submerged alluvial to shallow lacustrine deposition. Overlying these facies is loess-like deposition without bedding, distinguished by grain-size distribution, surface microtextures, and geochemical analysis, which is followed by palustrine deposition. In the palustrine deposition, aeolian sand-dune and sand-sheet deposition can be identified, which gradually developed upward in the Hekou Group, with intercalated wet interdunes, damp interdunes, and pebble-sand sheetflood beds. Finally, aeolian sand dunes and sand sheets dominated the upper Hekou Group. Overall, the upwardchanging facies indicated the development of aeolian deposition from an aqueous environment, revealing a long-term paleoclimatic shift from semi-humid, semi-arid to extremely arid, which reflects the expanded aeolian activity in East Asia during the Early Cretaceous. Furthermore, various records were combined to investigate the expanding aeolian activity in East Asia, which indicates a west--east-trending arid belt that was wider than the modern counterpart during the late Barremian--Early Aptian and late Aptian--Early Albian, respectively. These stepwise expansions of aeolian activity were mainly driven by rising atmospheric CO2, which strengthened the subsiding branches of Hadley circulation and the subtropical high, eventually leading to intensified aridification. [ABSTRACT FROM AUTHOR]

Ciprofloxacin is one of the antibiotics predominantly used to treat bacterial infections, however excess usage, and release of antibiotic from various sources to the environment can cause severe risks to human health since it was considered as emerging pollutant. This study deals with the intimately coupled photocatalysis and biodegradation (ICPB) of ciprofloxacin using gC 3 N 4 /CdS photocatalytic semiconductor and eco-friendly renewable loofah sponge as biocarrier in the ICPB. The photocatalyst gC 3 N 4 /CdS was prepared and their synergistic photocatalytic degradation of ciprofloxacin were assessed and the results shows that gC 3 N 4 /CdS (20%) exhibit 79% degradation efficiency in 36 h. Further ICPB exhibited enhanced ciprofloxacin degradation 95% at 36 h. The 62.4% and 81.1% of chemical oxygen demand (COD) removal was obtained in the photocatalysis and ICPB respectively. Enhanced degradation of ciprofloxacin and COD removal was due to the synergetic photoelectrons generated from the gC 3 N 4 /CdS (20%) transferred to the bacterial communities which intensely mineralize the degradation products produced from the photocatalysis process. Furthermore, production of hydroxyl •OH and superoxide radical anion O 2 • were identified actively involved in the degradation of ciprofloxacin. The biocarrier loofah sponge provided favourable environment to the bacterial communities for the formation of biofilm and production of extracellular polymeric substances (EPS). Excess quantity of EPS production in the ICPB helps in the prevention of toxicity of photocatalyst to bacterial communities as well as facilitate the extracellular electron transfer process. This work provides a novel path for enhanced degradation of ciprofloxacin using eco-friendly, low cost and renewable biocarrier loofah sponge in the ICPB system. [Display omitted] • Visible light active photocatalyst gC 3 N 4 /CdS effectively degrade ciprofloxacin. • ICPB demonstrate 95% of ciprofloxacin degradation and 81% of COD removal. • Lower band gap of gC 3 N 4 /CdS (20%) showed enhanced photocatalytic activity. • •OH and O 2 •– radicals played crucial role in the degradation of ciprofloxacin. [ABSTRACT FROM AUTHOR]

This research is to develop dictated metrics using a multi-proxy approach such as spatial-temporal analysis, statistical evaluation, and hydrogeochemical analysis. We have collected 45 groundwater samples located in the Tamirabarani river basin. To evaluate the aptness of developed metrics for agriculture and domestic needs and eleven years dataset has been analyzed and compared with national and international standards BIS, ICMAR, and WHO Monitoring and all the analysis results revealed that the concentration of calcium (Ca-1679 to 4937 mg/L; and Cl ions 236 to 1126 mg/L) and chloride ions was on the higher side in locations. These higher values may be attributed to the regional point sources as untreated water disposal and off-peak sources as agriculture practices. According to the results of the principal component analysis, the post-monsoon season accounted for an 84.2% variance. The major analyzed cations and anions have been observed in the following order: Na +  > Ca 2+  > Mg 2+  > K + and Cl -  > HCO 3 -  > SO 4 2-  > NO 3 - respectively. Ca-Mg-HCO 3 , Mg-Ca-Cl, Na-C1, and infused waters have been discovered in the basin region, indicating that anion and cation dominance is not prevalent. This specifies that groundwater quality in this region is significantly degraded and suffers from extensive salinity due to the urban pollutants mixed with unprotected river sites., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)