Karl Auerswald

Learn More
Carbon and nitrogen isotope signatures (delta(13)C and delta(15)N) of animal tissues provide information about the diet and, hence, the environment in which the animals are living. Hair is particularly useful as it provides a stable archive of temporal (e.g. seasonal) fluctuations in diet isotope composition. It can be sampled easily and with minimal(More)
Invasions of Ponto-Caspian gobiid fishes are suspected to cause regime shifts in freshwater ecosystems. This study compared the trophic niche differentiations of Neogobius melanostomus and Ponticola kessleri in the upper Danube River using stable isotope analyses (δ13C and δ15N), gut content analyses and morphometric analyses of the digestive tract. Both(More)
Water is the most important factor controlling plant growth, primary production, and ecosystem stability in arid and semi-arid grasslands. Here we conducted a 2-year field study to explore the contribution of winter half-year (i.e. October through April) and summer precipitation (May through September) to the growth of coexisting plant species in typical(More)
Grassed waterways (GWWs) drain surface runoff from fields without gullying along the drainageway. Secondary functions include reducing runoff volume and velocity and retaining sediments and harmful substances from adjacent fields. Grass cover (sward)-damaging sedimentation in the GWW is commonly reduced by frequent mowing, but in doing so the effectiveness(More)
Biases in the analysis of stable isotope discrimination in food webs Karl Auerswald*, Maximilian H. O. M. Wittmer, Antoine Zazzo, Rudi Schäufele and Hans Schnyder Lehrstuhl Für Grünlandlehre, Technische Universität München, Am Hochanger 1, D-85350 Freising-Weihenstephan, Germany; and CNRS Muséum national d’Histoire naturelle, UMR 7209 ‘‘Archéozoologie,(More)
The carbon isotope composition (dC) of C3/C4 mixed grassland is reflected in the dC of diet, hair or faeces of grazers, if C discrimination (D) between grassland vegetation and these tissues is known and constant. However, these relationships could be modified by selective grazing or differential digestibility of the C3 and C4 components, potentially(More)
Understanding the patterns and drivers of carbon isotope discrimination in C(4) species is critical for predicting the effects of global change on C(3)/C(4) ratio of plant community and consequently on ecosystem functioning and services. Cleistogenes squarrosa (Trin.) Keng is a dominant C(4) perennial bunchgrass of arid and semi-arid ecosystems across the(More)
Variation in the computation of slope from digital elevation data can result in significantly different slope values and can, in turn, lead to widely varying estimates of environmental phenomena such as soil erosion that are highly dependent on slope. Ten methods of computing slope from distributed elevation data, utilizing capabilities inherent in five(More)
Recently a rainfall erosivity map has been published. We show that the values of this map contain considerable bias because (i) the temporal resolution of the rain data was insufficient, which likely underestimates rain erosivity by about 20%, (ii) no attempt had been included to account for the different time periods that were used for different countries,(More)
The nitrogen isotope composition (δ¹⁵N) of different amino acids carries different dietary information. We hypothesized that transamination and de novo synthesis create three groups that largely explain their dietary information. Rats were fed with ¹⁵N-labeled amino acids. The redistribution of the dietary ¹⁵N labels among the muscular amino acids was(More)