11 - Darnajoux, R.,Zhang, R., Luxem, K. & Zhang X., The ammonium sensitivity of biological nitrogen fixation in sulfate-reducing diazotrophs and coastal salt marsh sediments. submitted
Highlight Highlight: We studied the time response and sensitivity of anaerobic sulfate reducers to fixed-N addition in pure culture and coastal sediments. We found compelling evidence that N fixation in those ecosystems is sensitive to low concentrations of NH4+, contradicting multiple reports on the presence of nitrogen fixation in N rich sediment.
10 - Meehan, M. L., Barreto, C., Turnbull, M. S., Bradley, R. L., Bellenger, J.-P., Darnajoux, R., Lindo, Z., Response of soil fauna to simulated global change factors depends on ambient climate conditions. submitted
Highlight Highlight: This study, the first report from the mini-Forced-Air CO2 Enrichment (Mini FACE) field experiment, investigate the response of soil microarthropod to simulated climate change condition (CO2, Temperature and N addition). The results highlight that annual rainfall may dictate soil faunal response to simulated climate change.
9 - Bellenger J.P., Darnajoux, R., Zhang, X., Kraepiel, A.M.L., (2020) Biological nitrogen fixation by alternative nitrogenases in terrestrial ecosystems: A review. Biogeochemistry, 149:53–73
Highlight Journal Highlight: This review summarizes current knowledge on the role and importance of alternative nitrogenases in terrestrial ecosystems. Many of the field-based demonstrations of V-nitrogenase contribution to BNF come from my Ph.D. and postdoc research. This review will promote this fast-emerging research topic and ensure the efficient dissemination of my work.
8 - Darnajoux, R., Magain, N., Renaudin, M., Lutzoni, F., Bellenger, J.P., Zhang, X. (2019) Molybdenum threshold for ecosystem-scale alternative vanadium nitrogenase activity in boreal forests. Proceeding of the National Academy of Science of the United States of America, 116(49) 24682-88
Highlight Journal Highlight: This is the first demonstration of the biome-scale activity of V-nitrogenase in the environment (15-50% of samples nitrogen fixation), and it shows that low Mo availability is the main driver. It calls for a re-evaluation of our nitrogen input estimates and our conceptual model for N fixation in natural, Mo-limited ecosystems.
7 - Darnajoux, R., Bradley, R., Houle, D., Bellenger, J. P. (2018), Predictable spatial patterns of biological nitrogen fixation in forest floor mosses: Color matters!. Soil Biology and Biochemistry, 122, 160-62, doi: 10.1016/j.soilbio.2018.04.010
Highlight Journal Highlight: This study shows that the phenotype “color” of moss shoots is a good predictor of their nitrogen status and thus can help predict the heterogeneity in the biological nitrogen fixation activity of boreal moss carpet at the plot scale. This is an important variable to consider when testing the effect of environments parameters (nutrient limitation, etc…), and it can also open the possibility of developing remote sensing tools for probing biological nitrogen fixation activity at the biome scale.
6 - Darnajoux, R., Zhang, X., McRose, D. L., Miadlikowska, J., Lutzoni, F., Kraepiel, A. M. L. and Bellenger, J.-P. (2017), Biological nitrogen fixation by alternative nitrogenases in boreal cyanolichens: importance of molybdenum availability and implications for current biological nitrogen fixation estimates. New Phytologist, 213: 680–689. doi:10.1111/nph.14166
Highlight Journal Highlight: This report uses evidences from genomics, metal homeostasis and isotopic biogeochemistry to demonstrate the first proof of activity of V-nitrogenase in the environment (concomitantly with Zhang et al. 2016, that describe the isotopic method that discriminate alternative Nase activity from Mo nitrogenase) as well as an indirect link of this activity to Mo availability. The activity of the V-Nase in the Nostoc partner of boreal cyanolichens is significant enough (20-30% of total nitrogen fixation) to call for a re-evaluation of our conceptual model of the coupling between trace metal (Mo, V, Fe) and major nutrient (N and C) cycles.
5 - Zhang, X., McRose, Darnajoux, R., Bellenger, J. P., Morel, F.M.M., & Kraepiel, A.M.L. (2016), Alternative nitrogenase activity in the environment and nitrogen cycle implications. Biogeochemistry, 127(2), 189-98, doi:10.1007/s10533-016-0188-6.
4 - Jouogo-Noumsi, C., Pourhassan, N., Darnajoux, R., Deicke, M., Wichard, T., Burrus, V. & Bellenger, J. P. (2016), Effect of organic matter on nitrogenase metal cofactor homeostasis in Azotobacter vinelandii under diazotrophic condition. Environmental Microbiology Report, 8, 76–84 doi:10.1111/1758-2229.12353
3 - Darnajoux R., Lutzoni F., Miadlikowska J., and Bellenger J. P. (2015), Determination of elemental baseline using peltigeralean lichens from Northeastern Canada (Québec): Initial data collection for long term monitoring of the impact of global climate change on boreal and subarctic area in Canada. Science of the Total Environment, 533, 1-7.
Highlight Journal Highlight: This study demonstrates that most part of northeastern Canadian boreal forest floor receive very low input of important micronutrient of the N and C cycle (Mo, Fe, Cu, etc…) from atmospheric deposition, with values as low as for remote or high elevation areas of the world (Antarctica, Patagonia, Alps). This finding has important implication for our understanding of global nutrient cycling in the boreal ecosytems, where up to 50% of the total nitrogen input occurs in moss carpet, which solely rely on atmospheric deposition for their micronutrient sources.
2 - Darnajoux R., Constantin J., Miadlikowska J., Lutzoni F. and Bellenger J.P. (2014), Is vanadium a biometal for boreal cyanolichens?. New Phytologist, vol202: 765-771
1 - Allard P., Darnajoux R., Phalyvong K. and Bellenger J.P. (2013), Effects of tungsten and titanium oxide nanoparticles on the diazotrophic growth and metals acquisition by Azotobacter vinelandii under molybdenum limiting condition. Environmental Science and Technology, vol 47: 2061-2068