The development of hyperspectral core scanning has facilitated high spatial/temporal pigment reconstructions indicative of changes in bioproductivity and was so far limited to those bacteriochlorophylls derived from Chromatiaceae (purple sulfur bacteria) to reconstruct changes in water column redox conditions and meromixis. This is the first study that reconstructs and quantifies Chlorobi-derived bacteriochlorophylls and its derivatives at high resolution in lake sediments. Therefore, this paper yields more insight into temporal variations of oxygenic and anoxygenic phototrophic communities, and provides a non-destructive tool for more detailed reconstructions of photic zone euxinia in meromictic lakes.

This study is the first to quantify land carbon cycle feedbacks under decreasing atmospheric CO2 concentration following negative CO2 emissions and compare them to feedbacks under positive emissions. The novel approach presented here reduces the carbon cycle inertia in the phase where atmospheric CO2 concentration decreases in order to improve the quantification of carbon cycle feedbacks under negative emissions. This approach reduced the effectivity of negative emissions in reducing atmospheric CO2, due to larger concentration-carbon and climate-carbon feedbacks.

Marine warming and deoxygenation are projected to intensify and drive a relative decrease in global habitat viability penetrating to all depths with warming dominating at the surface and deoxygenation becomes increasingly important with depth. In a 2°C scenario of global warming, epipelagic species' habitat losses are generally in the order of 0.1-0.5 million km3, while mesopelagic habitat losses are 0.01-0.15 million km3 and demersal losses are in the order of about 0.00025 million km3.

Nitrite is a nexus in nitrogen turnover, especially in oxygen minimum zones. This study works out new details of its specific role and adds new evidence for anaerobic nitrite oxidation. Furthermore, it shows that nitrogen recycling (nitrate reduction and nitrite oxidation) is quantitatively more important than loss processes.