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Microbial glycerol dialkyl glycerol tetraethers (GDGTs) in lacustrine sediments are widely used to reconstruct terrestrial paleoenvironments. However, lipids of diverse origin in lakes make it difficult to decipher environmental information, appealing for the necessity to evaluate the impact of terrigenous input on the distribution of GDGTs through long-term monitoring. In this study, we conducted two-year monitoring of GDGTs along the river, estuary, near shore, to the center of Lake Liangzi in central China. By comparing the spatiotemporal changes of GDGT distribution in suspended particulate matter (SPM) and surface sediments, we found that the archaeal isoprenoid GDGTs (isoGDGTs) were mainly produced in situ in the river-lake systems, and not affected by the soil input. In contrast, the bacterial branched GDGTs (brGDGTs) were affected, to some extent, by soil input, depending on the distance to the lakeshore. The soil input of brGDGTs was enhanced during an episode of abnormal rainfall (flood). Moreover, the large variation of isoGDGTs indicates the in situ production under the anoxic condition in lake water. The paired increase in the GDGT-0/Cren ratio and GDGT concentration might be diagnostic of flooding events in ancient times. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the archaeal and bacterial glycerol dialky glycerol tetraether (GDGT) distributions in the surface soils across various altitudes in Mount Jianfengling in Hainan Province, South China. Samples of surface soils were collected from a tropical rainforest in Mount Jianfengling. Results of the study showed a higher correlation between the atmosphere and altitude than the soils. It also found that the bacterial branched GDGTs dominated all samples.

The article focuses on a study which examined the mass extinction event in the Paleo-Tethys Ocean or the Kamura event. Samples of fresh carbonate were collected from the Shangsi and Laibin Sections in China. Results of the study showed variations in the carbon isotope composition in the Laibin Section. The study also found that the high positive plateau of carbon isotope during the Capitanian period did not occur in the Tethyan Ocean.

The article focuses on a study which examined the biodiversity and hydro-ecological selection of testate amoebae from Dajiuhu peatland in Shennongjia, Central China. Samples were collected from microsites within the peatland. Results of the study showed high variations in the morphology of testate amoebae in 136 Sphagnum samples. The study observed that variations in shell morphology can be attributed to different moisture conditions in their habitat.

The article explores the use of the geobiological approach in the assessment of Chinese carbonate source rocks. A series of paleoecological and biogeochemical parameters were employed to represented organic carbon (OC). It notes that clastic rocks based on geobiological parameters are qualified source rocks, while good source rocks from carbonates have low total organic carbon (TOC) values. It also notes the broad range of habitat types for carbonate source rocks in the Yangtze platform.