http://www.sciencedirect.com/science/article/pii/S0022169419312326 The optical properties can characterize the chemical composition, bioavailability and origins of dissolved organic matter (DOM), and thus indicate its biodegradability in natural waters. However, there remains a large gap in how DOM optical properties (UV-visible and fluorescence spectra) trace and predict the dissolved organic carbon biodegradation (%BDOC) in river systems. Over a 56-day laboratory incubation experiment, we examined the variations of %BDOC and DOM optical properties in a headwater tributary of the upper Yangtze River. We found that DOC biodegradability was significantly higher in the tributaries (20°C: 38.9 ± 19.8%; 30°C: 58.6 ± 19.5%) than that in the main stem (20°C: 26.1 ± 18.2%: 30°C: 41.8 ± 16.3%) (p < 0.001). The %BDOC, exhibiting coincident peaks in the agricultural regions and troughs in the ecologically fragile regions, increased by a factor of two- fold with a temperature gradient of 10℃. The optical properties SUVA and S 254 275- decreased, while the S , FI and BIX increased after the incubations, implying the synchronous 295 350-400 via biodegradation and production of young DOMs microbial respiration. The %BDOC:DOC tightly linked to a , S , S and BIX, illustrating that optical properties could predict the riverine %BDOC. The 254 275-295 350-400 findings demonstrated that optical properties could be regarded as the useful tracers of DOM biodegradation in river systems.

Ni, Z., Chen, Z., Li, M., Yang, C., Wen, L., Hong, H., Luo, B., 2020. Trace element characterization of bitumen constraints on the hydrocarbon source of the giant gas field in Sichuan Basin, South China. Geological Journal 55, 317-329.

https://doi.org/10.1002/gj.3412 6 3 The exploration of high production, natural gas wells (>10 m /d) has been extremely successful in the Gaoshiti and Moxi areas of the Leshan -Longnvsi paleo-uplift, in the west-central Sichuan Basin. This paper focuses on the Sinian and Cambrian reservoirs from the Gaoshiti and Moxi areas, where a dataset of new trace elements in bitumen and potential source rock is reported and where hydrocarbon-source correlation is attempted based on trace elements characteristics of the 12 potential source rocks and 22 bitumen samples. Results show that the bitumen from the three reservoirs can be distinguished from each other using trace element distribution patterns and redox- and provenance-sensitive elemental ratios. Bitumen in the second and fourth members of the Sin ian Dengying Formation were derived primarily from the third member of the source rocks of the Dengying Formation, which represents a self-sourced paleo-petroleum system. In contrast, bitumen in the reservoirs of the Cambrian Longwangmiao Formation is derived from the Cambrian Qiongzhusi Formation and third member of Dengying Formation. The trace element method used in this study improves our understanding of the complex hydrocarbon - source relation and confirm the potential target for petroleum exploration in the study area.

Nielsen, S.D., Koren, K., Löbmann, K., Hinge, M., Scoma, A., Kjeldsen, K.U., Røy, H., 2020. Constraints on CaCO precipitation in superabsorbent polymer by aerobic bacteria. Applied Microbiology and Biotechnology 3 104, 365-375.

https://doi.org/10.1007/s00253-019-10215-4 Microbially induced CaCO precipitation (MICP) can give concrete self-healing properties. MICP agents are 3 typically bacterial endospores which are coated into shelled granules, infused into expanded clay, or embedded into superabsorbent polymer (SAP). When small cracks appear in the cured concrete, the encapsulation is broken and the metabolic CO production from the germinated bacteria causes healing of the cracks by 2 precipitation of CaCO . Such systems are being tested empirically at large scales, but survival of endospores 3 through preparation and application, as well as germination and growth kinetics of the germinated vegetative Bacillus subtilis Bacillus alkalinitrilicus cells, remains poorly resolved. We encapsulated endospores of and in B. crosslinked acrylamide-based SAP and quantified their germination, growth, and, in the case of alkalinitrilicus , CaCO precipitation potential. The endospores survived crosslinking and desiccation inside the 3 polymer matrix. Microcalorimetry and microscopy showed that ~ 80% of the encapsulated endospores of both strains readily germinated after rehydration of freeze-dried SAP. Germinated cells grew into dense colonies of B. alkalinitrilicus cells inside the SAP, and those of calcified with up to 0.3 g CaCO produced per g desiccated 3 SAP when incubated aerobically. Measurements by planar optodes indicated that the precipitation rates were