ORCID Profile
0000-0002-7147-1008
Current Organisation
University of Hamburg
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Springer Science and Business Media LLC
Date: 13-06-2016
DOI: 10.1038/NCLIMATE3054
Publisher: Wiley
Date: 08-02-2021
DOI: 10.1111/EJSS.13088
Abstract: The application of biochar to agricultural soils to increase nutrient availability, crop production and carbon sequestration has gained increasing interest but data from field experiments on temperate, marginal soils are still under‐represented. In the current study, biochar, produced from organic residues (digestates) from a biogas plant, was applied with and without digestates at low (3.4 t ha −1 ) and intermediate (17.1 t ha −1 ) rates to two acidic and sandy soils in northern Germany that are used for corn ( Zea mays L.) production. Soil nutrient availability, crop yields, microbial biomass and carbon dioxide (CO 2 ) emissions from heterotrophic respiration were measured over two consecutive years. The effects of biochar application depended on the intrinsic properties of the two tested soils and the biochar application rates. Although the soils at the fallow site, with initially low nutrient concentrations, showed a significant increase in pH, soil nutrients and crop yield after low biochar application rates, a similar response was found at the cornfield site only after application of substantially larger amounts of biochar. The effect of a single dose of biochar at the beginning of the experiment diminished over time but was still detectable after 2 years. Whereas plant available nutrient concentrations increased after biochar application, the availability of potentially phytotoxic trace elements (Zn, Pb, Cd, Cr) decreased significantly, and although slight increases in microbial biomass carbon and heterotrophic CO 2 fluxes were observed after biochar application, they were mostly not significant. The results indicate that the application of relatively small amounts of biochar could have positive effects on plant available nutrients and crop yields of marginal arable soils and may decrease the need for mineral fertilizers while simultaneously increasing the sequestration of soil organic carbon. A low rate of biochar increased plant available nutrients and crop yield on marginal soils. Biochar application reduced the availability of potentially harmful trace elements. Heterotrophic respiration showed no clear response to biochar application. Biochar application may reduce fertilizer need and increase carbon sequestration on marginal soils.
Publisher: Elsevier BV
Date: 04-2011
Publisher: Springer Netherlands
Date: 2009
Publisher: Elsevier BV
Date: 09-2011
Publisher: Springer Science and Business Media LLC
Date: 07-12-2021
DOI: 10.1038/S41467-021-27386-2
Abstract: In contrast to the well-recognized permafrost carbon (C) feedback to climate change, the fate of permafrost nitrogen (N) after thaw is poorly understood. According to mounting evidence, part of the N liberated from permafrost may be released to the atmosphere as the strong greenhouse gas (GHG) nitrous oxide (N 2 O). Here, we report post-thaw N 2 O release from late Pleistocene permafrost deposits called Yedoma, which store a substantial part of permafrost C and N and are highly vulnerable to thaw. While freshly thawed, unvegetated Yedoma in disturbed areas emit little N 2 O, emissions increase within few years after stabilization, drying and revegetation with grasses to high rates (548 (133–6286) μg N m −2 day −1 median with (range)), exceeding by 1–2 orders of magnitude the typical rates from permafrost-affected soils. Using targeted metagenomics of key N cycling genes, we link the increase in in situ N 2 O emissions with structural changes of the microbial community responsible for N cycling. Our results highlight the importance of extra N availability from thawing Yedoma permafrost, causing a positive climate feedback from the Arctic in the form of N 2 O emissions.
Location: Germany
Location: No location found
No related grants have been discovered for Christian Knoblauch.