Element cycles in forests and grasslands of the Biodiversity Exploratories: Response to management intensity and associated biodiversity
Final Report Abstract
Land use and associated biodiversity strongly affect the cycling of carbon and nutrients in terrestrial ecosystems. The BECycles project tested effects of land use intensity and associated shifts in biodiversity on water, dissolved organic C and nutrient fluxes and the composition of dissolved organic matter in forest and grassland ecosystems. Tree species affected the generation of particulate organic carbon and N leaching in forest canopies, which was likely related to tree species-specific phyllosphere microbial communities. Production and consumption of dissolved organic matter differed between beech forests and coniferous forests, reflecting biological controls of these processes in aboveground strata of forest ecosystems. In contrast, retention of dissolved organic matter in minerals subsoils was likely controlled by soil chemical processes (sorption and coagulation). Nitrogen leaching from the organic layers of beech forests decreased with increasing plant diversity, while soil fauna biomass had a positive effect on N leaching. This highlights that N leaching from organic layers is driven by the complex interplay of plants, animals and microbes. Bayesian modeling of nitrate and ammonium concentrations in soil solutions revealed that abiotic variables like sand content, soil moisture and soil temperature are important predictors of the soil nitrogen dynamics, in addition to biotic predictors like the contribution of legumes and grasses to the total species number, microbial nitrogen, urease activity, number of earthworms, total N in roots, and the number of insect larvae. The Bayesian models further allowed for the extrapolation of the measured NO3-N and NH4+ -N concentrations in soil solution of 29 grassland plots to all 150 experimental grassland plots in the three Exploratories, resulting in comprehensive data set that can be used for further integrative analyses. Overall, our results suggest that the effects of land use type and intensity and associated biodiversity on the cycling of carbon and nutrients in forests and grasslands via biological controls of aboveground processes are dampened by chemical and physical soil processes.
Publications
- More efficient aboveground nitrogen use in more diverse Central European forest canopies, For. Ecol. Manage. 313: 274-282, 2014
Schwarz, T.M.; Bischoff, S.; Blaser, S.; Boch, S.; Schmitt, B.; Thieme, L.; Fischer, M.; Michalzik, B.; Schulze, E.-D.; Siemens, J.; Wilcke, W.
(See online at https://doi.org/10.1016/j.foreco.2013.11.021) - Biotic and abiotic controls of nitrogen and phosphorus cycling in Central European forests. Dissertation, Philosophisch-Naturwissenschaftliche Fakultät, Universität Bern, 164 p, 2015
Schwarz, T
- Properties of dissolved and total organic matter in throughfall, stemflow and forest floor leachate of central European forests, Biogeosciences, 12, 2695-2706, 2015
Bischoff, S., Schwarz, M. T., Siemens, J., Thieme, L., Wilcke, W., and Michalzik, B.
(See online at https://doi.org/10.5194/bg-12-2695-2015) - Drivers of nitrogen leaching from organic layers in Central European beech forests, Plant Soil, 403: 343-360, 2016
Schwarz, M.T., Bischoff, S., Blaser, S., Boch, S., Grassein, F., Klarner, B., Schmitt, B., Solly, E.F., Ammer, C., Michalzik, B., Schall, P., Scheu, S., Schöning, I., Schrumpf, M., Schulze, E-D., Siemens, J., Wilcke, W.
(See online at https://doi.org/10.1007/s11104-016-2798-0) - Fast-freezing with liquid nitrogen preserves bulk dissolved organic matter concentrations, but not its composition, Biogeosciences, 13, 4697-4705, 2016
Thieme, L., Graeber, D., Kaupenjohann, M., and Siemens, J.
(See online at https://doi.org/10.5194/bg-13-4697-2016) - Dissolved organic matter in differently managed forest ecosystems. Dissertation, Fakultät VI Planen Bauen Umwelt, TU Berlin, 76 p, 2018
Thieme, L.
(See online at https://doi.org/10.14279/depositonce-6870) - Does plant diversity affect the water balance of established grassland systems?, Ecohydrology, 2018;11:e1945, 2018
Leimer, S., Bischoff, S., Boch, S., Busch, V., Escher, P., Fischer, M., Hänsel, F., Hölzel, N.,Kerber, K., Klaus, V.H., Kleinebecker, T., Michalzik, B., Nauss, T., Schäfer, D., Schöning, I., Schwarz, M.T., Siemens, J., Thieme, T., Wöllauer, S., Wilcke, W.
(See online at https://doi.org/10.1002/eco.1945) - Dissolved organic matter characteristics of deciduous and coniferous forests with variable management: different at the source, aligned in the soil, Biogeosciences Discuss., 2019
Thieme, L., Graeber, D., Hofmann, D., Bischoff, S., Schwarz, M. T., Steffen, B., Meyer, U.-N., Kaupenjohann, M., Wilcke, W., Michalzik, B., Siemens J.
(See online at https://doi.org/10.5194/bg-2018-478)
