Max Planck Institutes and Experts

The Earth works like a power plant generating energy out of its planetary drivers. This energy maintains the winds in the atmosphere, ocean currents, and global biogeochemical cycles such as the hydrological cycle. The laws of thermodynamics set the limits to the rates by which these forms of energy are generated and thereby limit the forms of energy that could potentially be used as renewable energy. The global estimate shows that - except for solar and wind power - the natural generation rates of renewable energy are rather small and in the order of the human energy consumption.

Large amounts of methane are produced in the biosphere and released into the atmosphere. The junior research group ORCAS at the Max Planck Institute for Chemistry explores new sources of methane in the environment and describes the underlying formation mechanisms. Fungi are an important component of terrestrial biological communities. Just recently, the researchers showed that fungi also release methane in their metabolism. But it is still unknown to what extent this new source of methane contributes to the methane balance of terrestrial ecosystems.

The biogenic emission of nitric oxide (NO) from natural and agriculturally managed soils of the terrestrial drylands is largely unknown, but of high importance for the local and regional air chemistry. The basic spatio-temporal scales of NO-emission ranges from a few cm² to km², and from some minutes to months. A full suite of experimental methods (laboratory incubation of soil samples to remote sensing) is applied to cover these scales for overlapping quantification of the unknown NO-emissions.

Climate Engineering employs technical methods to mitigate climate change without lowering anthropogenic CO₂ emissions. One of these methods, the artificial increase of ocean alkalinity, has been proposed to enhance the oceanic uptake of atmospheric CO₂ and counteract the ongoing ocean acidification. We used a global biogeochemical model to show that artificial ocean alkalinity input must be 200 times higher than the input by natural weathering flux to hold the global seawater pH close to today’s value. The effects on ocean biogeochemistry would be substantial.

New plant diseases emerge regularly being a threat for food security. Some pathogens cause epidemics on living plants only and are called biotrophs. Comparative genomics revealed a loss of essential metabolic pathways leading to biotrophy. However, gene loss is only possible due to the ability to suppress host defense. Defense suppression and adaptability requires a large gene pool that is acquired by sexual recombination or interaction with other organisms. To get a comprehensive view on how new pathogens emerge it is important to dissect their interaction within natural habitats.