84
5.12 Conclusions
N 2 fixation rates continue to be measured by traditional C 2 H 2 reduction and
15
N 2
uptake techniques, but there have been many advances and the introduction of new
approaches, such as biochemical assays, molecular biological and genetic methods,
measurements of H 2 production, isotopically labeled acetylene and stable isotope
probing. Mathematical models that predict N 2 fixation from nutrient and/ or diazotrophic species distributions provide large-scale forcasts important for understanding the role of N 2 fixation in the current and future oceans and the upward trend in
computing power and model sophistication will continue. Greater access to more
user-friendly costs instrumentation such as mass spectrometers and greatly decreasing sequencing cost have been major factors in propelling N 2 fixation research forward.The advent of high resolution underway samping for activity and autonomous
systems for genetic analysis are examples of recent advances and indicative of
future trends. Nonetheless, all of the methods have limitations and weaknesses
which need to be accounted for and methods development continues to be important
for marine N 2 fixation research.
References
Amann, R. I., Ludwig, W., & Schleifer, K.-H. (1995). Phylogenetic identification and in situ detection of individual microbial cells without cultivation. Microbiological Reviews, 59(1), 143–169.
An, S. M., Gardner, W. S., & Kana, T. (2001). Simultaneous measurement of denitrification and
nitrogen fixation using isotope pairing with membrane inlet mass spectrometry analysis.
Applied and Environmental Microbiology, 67(3), 1171–1178.
Archer, M., Li, Z., & Fu, L. L. (2020). Increasing the space-time resolution of mapped sea surface
height from altimetry. Journal of Geophysical Research, Oceans, 125(2), e2019JC015878.
Behrenfeld, M. J., & Falkowski, P. G. (1997). Photosynthetic rates derived from satellite-based
chlorophyll concentration. Limnology and Oceanography, 42(1), 1–20.
Behrens, S., Lösekann, T., Pett-Ridge, J., Weber, P. K., Ng, W.-O., et al. (2008). Linking microbial phylogeny to metabolic activity at the single-cell level by using enhanced element
labeling-catalyzed reporter deposition fluorescence in situ hybridization (EL-FISH) and
NanoSIMS. Applied and Environmental Microbiology, 74(10), 3143–3150.
Bentzon-Tilia, M., Severin, I., Hansen, L. H., & Riemann, L. (2015a). Genomics and ecophysiology of heterotrophic nitrogen-fixing bacteria isolated from estuarine surface water. MBio, 6(4),
e00929-00915.
Bentzon-Tilia, M., Traving, S. J., Mantikci, M., Knudsen-Leerbeck, H., Hansen, J. L. S., et al.
(2015b). Significant N 2 fixation by heterotrophs, photoheterotrophs and heterocystous cyanobacteria in two temperate estuaries. The ISME Journal, 9(2), 273–285.
Bergman, B., & Carpenter, E. J. (1991). Nitrogenase confined to randomly distributed trichomes
in the marine cyanobacterium Trichodesmium thiebautii. Journal of Phycology, 27, 158–165.
Blondeau-Patissier, D., Brando, V. E., Lønborg, C., Leahy, S. M., & Dekker, A. G. (2018).
Phenology of Trichodesmium spp. blooms in the Great Barrier Reef lagoon, Australia, from the
ESA-MERIS 10-year mission. PLoS One, 13(12), e0208010.
Bombar, D., Paerl, R. W., Anderson, R., & Riemann, L. (2018). Filtration via conventional glass
fiber filters in
15 N 2 tracer assays fails to capture all nitrogen-fixing prokaryotes. Frontiers in
Marine Science, 5, 6.
5 Measurements of Organism Abundances and Activities
5.12 Conclusions
N 2 fixation rates continue to be measured by traditional C 2 H 2 reduction and
15
N 2
uptake techniques, but there have been many advances and the introduction of new
approaches, such as biochemical assays, molecular biological and genetic methods,
measurements of H 2 production, isotopically labeled acetylene and stable isotope
probing. Mathematical models that predict N 2 fixation from nutrient and/ or diazotrophic species distributions provide large-scale forcasts important for understanding the role of N 2 fixation in the current and future oceans and the upward trend in
computing power and model sophistication will continue. Greater access to more
user-friendly costs instrumentation such as mass spectrometers and greatly decreasing sequencing cost have been major factors in propelling N 2 fixation research forward.The advent of high resolution underway samping for activity and autonomous
systems for genetic analysis are examples of recent advances and indicative of
future trends. Nonetheless, all of the methods have limitations and weaknesses
which need to be accounted for and methods development continues to be important
for marine N 2 fixation research.
References
Amann, R. I., Ludwig, W., & Schleifer, K.-H. (1995). Phylogenetic identification and in situ detection of individual microbial cells without cultivation. Microbiological Reviews, 59(1), 143–169.
An, S. M., Gardner, W. S., & Kana, T. (2001). Simultaneous measurement of denitrification and
nitrogen fixation using isotope pairing with membrane inlet mass spectrometry analysis.
Applied and Environmental Microbiology, 67(3), 1171–1178.
Archer, M., Li, Z., & Fu, L. L. (2020). Increasing the space-time resolution of mapped sea surface
height from altimetry. Journal of Geophysical Research, Oceans, 125(2), e2019JC015878.
Behrenfeld, M. J., & Falkowski, P. G. (1997). Photosynthetic rates derived from satellite-based
chlorophyll concentration. Limnology and Oceanography, 42(1), 1–20.
Behrens, S., Lösekann, T., Pett-Ridge, J., Weber, P. K., Ng, W.-O., et al. (2008). Linking microbial phylogeny to metabolic activity at the single-cell level by using enhanced element
labeling-catalyzed reporter deposition fluorescence in situ hybridization (EL-FISH) and
NanoSIMS. Applied and Environmental Microbiology, 74(10), 3143–3150.
Bentzon-Tilia, M., Severin, I., Hansen, L. H., & Riemann, L. (2015a). Genomics and ecophysiology of heterotrophic nitrogen-fixing bacteria isolated from estuarine surface water. MBio, 6(4),
e00929-00915.
Bentzon-Tilia, M., Traving, S. J., Mantikci, M., Knudsen-Leerbeck, H., Hansen, J. L. S., et al.
(2015b). Significant N 2 fixation by heterotrophs, photoheterotrophs and heterocystous cyanobacteria in two temperate estuaries. The ISME Journal, 9(2), 273–285.
Bergman, B., & Carpenter, E. J. (1991). Nitrogenase confined to randomly distributed trichomes
in the marine cyanobacterium Trichodesmium thiebautii. Journal of Phycology, 27, 158–165.
Blondeau-Patissier, D., Brando, V. E., Lønborg, C., Leahy, S. M., & Dekker, A. G. (2018).
Phenology of Trichodesmium spp. blooms in the Great Barrier Reef lagoon, Australia, from the
ESA-MERIS 10-year mission. PLoS One, 13(12), e0208010.
Bombar, D., Paerl, R. W., Anderson, R., & Riemann, L. (2018). Filtration via conventional glass
fiber filters in
15 N 2 tracer assays fails to capture all nitrogen-fixing prokaryotes. Frontiers in
Marine Science, 5, 6.
5 Measurements of Organism Abundances and Activities