Karin Potthast

  • Citations Per Year
Learn More
Microorganisms are vital in mediating the earth's biogeochemical cycles; yet, despite our rapidly increasing ability to explore complex environmental microbial communities, the relationship between microbial community structure and ecosystem processes remains poorly understood. Here, we address a fundamental and unanswered question in microbial ecology:(More)
Global change phenomena, such as forest disturbance and land-use change, significantly affect elemental balances as well as the structure and function of terrestrial ecosystems. However, the importance of shifts in soil nutrient stoichiometry for the regulation of belowground biota and soil food webs have not been intensively studied for tropical(More)
Land-use type and ecosystem disturbances are important drivers for element cycling and bear the potential to modulate soil processes and hence ecosystem functions. To better understand the effect of such drivers on the magnitude and temporal patterns of organic matter (OM) and associated nutrient fluxes in soils, continuous flux monitoring is indispensable(More)
The influence of water activity (25-65% r.h.) on the changes in activity of glycolytic enzymes during storage (up to 120 days) of freeze-dehydrated bovine muscle was investigated. For this purpose, at different times of storage the decrease of glycogen and the increase in lactate in the rehydrated samples were determined. At 25% r.h. no loss in activity was(More)
During storage of freeze-dehydrated bovine muscle triglycerides and cholesterolesters are slowly hydrolyzed even at 25% relative humidity (r.h.). The extent of lipid hydrolysis in the tissue increases with rising water activity, the final degree of hydrolysis being dependent on water activity. It has been demonstrated that these changes are due to the(More)
We present proteome data from the microbiota (feces) after a diet shift from a natural diverse to a monocultural meadow with Dactylis glomerata. The abundant grasshopper species, Chorthippus dorsatus, was taken from the wild and kept in captivity and were fed with Dactylis glomerata for five days. For phytophagous insects, the efficiency of utilization of(More)
Angular distributions of 7Li(7Li,t), (7Li,α) and (7Li,6He) reactions were measured for laboratory energies from 2 16 MeV. Exact finite range DWBA analyses were performed with the aim to identify contributions of direct processes and to investigate the applicability of DWBA to such few nucleon systems. It turned out that DWBA can be successfully applied to(More)
Changing fire regimes in response to climate change are likely to have significant effects on terrestrial ecosystems and biogeochemical cycles. While effects of fire on some nutrient cycles have been quite well-studied, little attention has been paid to the silicon cycle. We used an alkaline continuous extraction to examine changes in the quantity and(More)
During storage of prerigor freeze-dried beef, glycogen is not broken down even at 97.5% r.h. (moisture content of the meat about 30%). However, the metabolites of glycogen -- glucose, fructose, and their phosphoric acid esters -- are changed during storage at r.h. greater than 25%, mainly by the effect of glycolytic enzymes. Also nonenzymic reactions of the(More)
Little is known about how N and P co-limited ecosystems respond to single nutrient enrichment. This work assesses the susceptibility of above- and belowground ecosystem components and of their linkages in an N and P co-limited pasture to N- and P-enrichment. We tested if the plants’ responses can be explained by the concept of serially linked nutrients(More)