umu.sePublications
Change search
Link to record
Permanent link

Direct link
BETA
Maier, Dominique B.
Alternative names
Publications (8 of 8) Show all publications
Maier, D. B., Diehl, S. & Bigler, C. (2019). Interannual variation in seasonal diatom sedimentation reveals the importance of late winter processes and their timing for sediment signal formation. Limnology and Oceanography, 64(3), 1186-1199
Open this publication in new window or tab >>Interannual variation in seasonal diatom sedimentation reveals the importance of late winter processes and their timing for sediment signal formation
2019 (English)In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 64, no 3, p. 1186-1199Article in journal (Refereed) Published
Abstract [en]

Disentangling the process information contained in a diatom sediment signature is crucial for reliable future predictions based on paleolimnological records. In this study, we combine limnological and paleolimnological monitoring to address the fundamental question: Which environmental information is contained in a diatom sediment signal? We compared annual diatom sequential sediment trap records with the diatom record of the annually varved lake sediment of Nylandssjon (northern Sweden) from three meteorologically different years (2012-2014). The seasonal patterns in diatom sedimentation were strikingly different in varve years 2012 and 2014 compared to varve year 2013. In 2012 and 2014, up to 70% of the annual flux occurred in a single spring month and was dominated by Cyclotella glomerata. In contrast, in 2013, peak fluxes were much lower and more annually integrated. Next, we compared the full-year diatom trap results with year round in-lake physical, chemical, and biological monitored parameters, as well as meteorological variables. Annual averages of environmental conditions did not explain the interannual variability in diatom sedimentation. Instead, the seasonality of diatom sedimentation was determined by the timing of the spring diatom bloom relative to lake over-turn in winters with warm vs. cold air temperature. With our combined limnological and paleolimnological monitoring approach, we find that an annual diatom signal can either contain primarily seasonal climate information from a short time period or be annually integrated. We synthesize our results in a novel conceptual model, which describes the response of sediment diatom signals to two distinct sequences of late-winter conditions.

Place, publisher, year, edition, pages
Association for the Science of Limnology and Oceanography, 2019
National Category
Geology Climate Research
Identifiers
urn:nbn:se:umu:diva-159614 (URN)10.1002/lno.11106 (DOI)000467593600022 ()
Available from: 2019-06-17 Created: 2019-06-17 Last updated: 2019-06-17Bibliographically approved
Maier, D. B., Gälman, V., Renberg, I. & Bigler, C. (2018). Using a decadal diatom sediment trap record to unravel seasonal processes important for the formation of the sedimentary diatom signal. Journal of Paleolimnology, 60(2), 133-152
Open this publication in new window or tab >>Using a decadal diatom sediment trap record to unravel seasonal processes important for the formation of the sedimentary diatom signal
2018 (English)In: Journal of Paleolimnology, ISSN 0921-2728, E-ISSN 1573-0417, Vol. 60, no 2, p. 133-152Article in journal (Refereed) Published
Abstract [en]

Sediment trap studies and high frequency monitoring are of great importance to develop a deeper understanding of how seasonal environmental processes are imprinted in sediment signal formation. We collected whole year diatom assemblages from 2002 to 2014 with a sequential sediment trap from a varved boreal lake (Nylandssjon, Sweden) together with environmental and limnological parameters, and compared them with the corresponding diatom record of the annual laminated sediment. Our data set indicates a large year-to-year variability of diatom succession and abundance patterns, which is well reflected in the varved sediments. Specifically, Cyclotella glomerata dominated the annual sediment trap record (as well as in the corresponding sediment varves) in years with warmer air temperatures in March/April, and Asterionella formosa dominated the annual sediment assemblages as a consequence of years characterized by higher runoff before lake over-turn. Years succeeding forest clearance in the lake catchment showed marked increase in diatom and sediment flux. The DCA scores of the yearly diatom trap assemblages clearly resemble the lake's thermal structure, which indicates that the relative abundance of major taxa seems primarily controlled by the timing of seasonal environmental events, such as above-average winter air temperature and/or autumn runoff and the current thermal structure of the lake. The high seasonal variability between environmental drivers in combination with the physical limnology leaves us with several possible scenarios leading to either an A. formosa versus C. glomerata dominated annual diatom sediment signal. With this study we highlight that short-term environmental events and seasonal limnological conditions are of major importance for interpreting annual sediment signals.

Place, publisher, year, edition, pages
Springer, 2018
Keywords
Annual diatom flux, Sequential sediment trap, Varved lake sediments, Seasonal air temperature, Discharge, Catchment
National Category
Geology Ecology
Identifiers
urn:nbn:se:umu:diva-150660 (URN)10.1007/s10933-018-0020-5 (DOI)000437128400003 ()2-s2.0-85042094692 (Scopus ID)
Available from: 2018-08-28 Created: 2018-08-28 Last updated: 2020-02-03Bibliographically approved
Maier, D. B. (2017). Combining limnology and paleolimnology: a refined understanding of environmental sediment signal formation in a varved lake. (Doctoral dissertation). Umeå: Umeå University
Open this publication in new window or tab >>Combining limnology and paleolimnology: a refined understanding of environmental sediment signal formation in a varved lake
2017 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Paleoclimatic archives, such as lake sediments, extend our understanding of terrestrial and aquatic ecosystem dynamics in relation to climate variability beyond the period covered by instrumental data. In this context, annually laminated (i.e. varved) lake sediments are particularly valuable, as they offer high temporal resolution and undisturbed sediment. However, in order to extract reliable climate information from lake sediments, a careful calibration with the processes controlling the sediment formation is essential. This thesis combines limnological and paleolimnological data from a varved, boreal lake in northern Sweden (Nylandssjön, Nordingrå) collected over different time scales. The main aim of the thesis is to gain a more refined insight into which processes are reflected in the sedimentary diatom assemblage. More specifically, sequential sediment trap records were coupled with physical, chemical and biological lake monitoring and environmental data for comparison and validation with the varved sediment record. The main result of the thesis is that timing, succession and inter-annual variability of key limnological and environmental processes (e.g. ice-cover duration, lake over-turn or catchment run-off) are of major importance for the sedimentary diatom assemblage formation. Continuous monitoring of physico-chemical parameters over three consecutive years identified varying winter air temperature as a major factor influencing in-lake processes and hence the diatom record. Timing of lake over-turn and catchment run-off seemed to be the driver for monospecific diatom blooms, which are reflected in the annual sediment signal. The integrated annual diatom signal in the sediment was dominated by spring or autumn blooms, resulting either from a Cyclotella glomerata dominated spring bloom after relatively warm winter conditions, or a Asterionella formosa dominated autumn bloom after relatively cold winter conditions. The analysis of the diatom stratigraphy in the varved sediment over several decades corroborated the importance of climatic variables (late winter air temperature and NAO), even though the variables with the most predictive power for variance in the diatom data were associated with sediment composition (C, N and sedimentation rate) and pollution (Pb and Cu). Overall, the analysis of the drivers of inter-annual and decadal diatom assemblage fluctuations emphasizes the importance of winter air temperature, indicating that weather extremes may be disproportionately represented in annual sediment records in contrast to nutrient concentrations or sedimentation rate.

Place, publisher, year, edition, pages
Umeå: Umeå University, 2017. p. 29
Keywords
varved lake sediments, diatom sediment signal formation, sequential sediment trap, seasonal process timing, ice thinning, varve compaction, climate impact, catchment properties
National Category
Earth and Related Environmental Sciences
Research subject
Earth Sciences with Specialization Environmental Analysis
Identifiers
urn:nbn:se:umu:diva-135231 (URN)978-91-7601-603-9 (ISBN)
Public defence
2017-06-15, KB3A9, KBC, Umeå, 10:00 (English)
Opponent
Supervisors
Available from: 2017-05-24 Created: 2017-05-22 Last updated: 2018-06-09Bibliographically approved
Capo, E., Domaizon, I., Maier, D., Debroas, D. & Bigler, C. (2017). To what extent is the DNA of microbial eukaryotes modified during burying into lake sediments?: A repeat-coring approach on annually laminated sediments. Journal of Paleolimnology, 58(4), 479-495
Open this publication in new window or tab >>To what extent is the DNA of microbial eukaryotes modified during burying into lake sediments?: A repeat-coring approach on annually laminated sediments
Show others...
2017 (English)In: Journal of Paleolimnology, ISSN 0921-2728, E-ISSN 1573-0417, Vol. 58, no 4, p. 479-495Article in journal (Refereed) Published
Abstract [en]

Paleogenetics provides a powerful framework to reconstruct the long-term temporal dynamics of various biological groups from aquatic sediments. However, validations are still required to ensure the authenticity of the molecular signal obtained from sedimentary DNA. Here, we investigated the effects of early diagenesis on the DNA signal from micro-eukaryotes preserved in sediments by comparing metabarcoding inventories obtained for two sediment cores sampled in 2007 and 2013 respectively. High-throughput sequencing (Illumina MiSeq) of sedimentary DNA was utilized to reconstruct the composition of microbial eukaryotic communities by targeting the V7 region of the 18S rDNA gene. No significant difference was detected between the molecular inventories obtained for the two cores both for total richness and diversity indices. Moreover, community structures obtained for the two cores were congruent as revealed by procrustean analysis. Though most of the eukaryotic groups showed no significant difference in terms of richness and relative proportion according to the core, the group of fungi was found to differ both in terms of richness and relative proportion (possibly due to their spatial heterogeneity and potential activity in sediments). Considering the OTUs level (i.e. Operational Taxonomic Units as a proxy of ecological species), our results showed that, for the older analyzed strata (age: 15-40 years), the composition and structure of communities were very similar for the two cores (except for fungi) and the DNA signal was considered stable. However, for the uppermost strata (age < 15 years), changes of moderate magnitude were detected in the relative abundance of few OTUs. Overall, this study points out that, in Nylandssjon sediments, early diagenesis did not induce marked modifications in the micro-eukaryotic DNA signal, thus opening new perspectives based on the analysis of eukaryotic sedimentary DNA to address scientific issues both in the domains of paleolimnology and microbial ecology. Because this study site is ideal for DNA preservation in sediment (quick sedimentation processes, no sediment resuspension, anoxic conditions at sediment-water interface), the generalization of our conclusions, in particular for less favorable sites, must be considered cautiously.

Place, publisher, year, edition, pages
Springer, 2017
Keywords
eDNA, Paleogenetics, Sediment, Metabarcoding, Plankton
National Category
Microbiology
Identifiers
urn:nbn:se:umu:diva-142229 (URN)10.1007/s10933-017-0005-9 (DOI)000414421600004 ()
Available from: 2017-12-11 Created: 2017-12-11 Last updated: 2018-06-09Bibliographically approved
Maier, D. B., Rydberg, J., Bigler, C. & Renberg, I. (2013). Compaction of recent varved lake sediments. GFF, 135(3-4), 231-236
Open this publication in new window or tab >>Compaction of recent varved lake sediments
2013 (English)In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 135, no 3-4, p. 231-236Article in journal (Refereed) Published
Abstract [en]

To assess the rates of compaction in recent, varved (annually laminated) lake sediments, we used a collection of 13 freeze cores sampled from 1979 to 2012 in Nylandssjon (northern Sweden). This unique series of stored freeze cores allowed us to measure how the thickness of individual varves changed when they were overlain by new varves. The compaction rate was greatest during the first few years after deposition; varve thickness decreased by 60% after 5 years (sediment depth 5cm). Thereafter, the compaction rate declined, but after 33 years (the study period) there was still a weak trend of continued compaction (sediment depth 12cm). The rate of compaction is clearly linked to loss of water along with an increase in dry-bulk density of the sediment. Despite compaction causing considerable varve thickness changes over time, the year-to-year variation in varve thickness is preserved while sediment ages. Understanding compaction processes is of fundamental importance to paleolimnology, for example in studies involving calibration of varve thicknesses of recent varves against environmental parameters.

Place, publisher, year, edition, pages
Taylor & Francis, 2013
Keywords
varved lake sediment, compaction, varve thickness, bulk density, diagenesis, post-depositional changes, paleolimnology
National Category
Geology
Identifiers
urn:nbn:se:umu:diva-85095 (URN)10.1080/11035897.2013.788551 (DOI)000327571800002 ()
Note

Special Issue: Varve Genesis, Chronology and Paleoclimate

Available from: 2014-01-28 Created: 2014-01-28 Last updated: 2018-06-08Bibliographically approved
Maier, D. B.Annually resolved impact of climate and catchment properties on the sediment diatom assemblage in a varved, boreal lake since AD 1930.
Open this publication in new window or tab >>Annually resolved impact of climate and catchment properties on the sediment diatom assemblage in a varved, boreal lake since AD 1930
(English)Manuscript (preprint) (Other academic)
Abstract [en]

Assessing ecosystem dynamics beyond experimental time-scales is a prerequisite to understand effects of ongoing environmental change and essential to improve predictions of future conditions. In this study, we analyze a time series of an annually resolved sediment record from a boreal lake (Nylandssjön) in northern Sweden, consisting of diatom data since AD 1931 and geochemistry data since AD 1953. The aim of this paper is to quantify to which extent the main primary producers (i.e., diatom assemblage) in a typical boreal lake are related to processes in the lake catchment, sediment properties, and climate variables (temperature, precipitation, circulation patterns). The diatom assemblage consists mainly of Cyclotella taxa (C. glomerata, C. radiosa, and C. rossii), Asterionella formosa, Fragilaria delicatissima and other small Fragilaria taxa. Although the dominant taxa remain the same over the entire sediment record, their relative abundances exhibit some distinct shifts. We use ordination techniques and variance partitioning to quantify the explanatory power of environmental variables to explain shifts in the diatom assemblage composition. A series of redundancy analyses (RDA) using one sole constraining variable showed that both geochemical proxies and climate variables explained a statistically significant amount of the variance in the diatom data. The most powerful sediment proxy variables were Pb (ppm, 17.9%), C (%, 16.8%), N (%, 15.7%) and sedimentation rate (g cm-2 yr-1, 13.2%). For climate variables, temperature during winter/spring (April 6.4%, May 5.0%, February 4.6%) and the Northern Atlantic Oscillation index (NAO 6.4%) showed the highest predictive power, whereas precipitation data did not turn out to be a powerful predictor. Variance partitioning showed that sediment proxies (sedimentation rate, C, N; 20.8%), variables associated with pollution (Pb, Cu, P; 23.1%) and climate (winter/spring temperature, NOA; 10.4%) explained significant amounts of the variance in the diatom data. This quantification indicates to which extent sediment properties and climate conditions are jointly responsible for shaping the ecosystem properties in boreal lakes, highlighting in particular the importance of winter climate.

Keywords
Diatoms, geochemistry, boreal lake, varves, climate, variance partitioning
National Category
Climate Research
Identifiers
urn:nbn:se:umu:diva-135330 (URN)
Available from: 2017-05-23 Created: 2017-05-23 Last updated: 2018-06-09
Maier, D. B.Inter-annual variation of seasonal diatom dynamics reveals importance of process timing for sediment signal formation.
Open this publication in new window or tab >>Inter-annual variation of seasonal diatom dynamics reveals importance of process timing for sediment signal formation
(English)Manuscript (preprint) (Other academic)
Abstract [en]

Disentangling the process information contained in a diatom sediment signature is crucial for reliable future predictions based on paleolimnological records. The aim of this study was to identify the hierarchical importance of seasonal processes for the formation of an annual diatom sediment record. We combined annual vertical water column chemistry, lake thermal structure, sequential sediment trap samples and annually resolved varved sediment diatom records from a boreal lake in northern Sweden. Whole-year water column monitoring indicates that the entire annual diatom sediment signal in different years can be driven by winter air temperature-induced timing of ice and snow melt and persistent under-ice stratification, which promote an early diatom bloom under the ice before spring lake over-turn. In a year of late ice thinning and development of a chlorophyll maximum after spring lake over-turn, an annually integrated diatom sediment signal was built by a continuous diatom flux, with important implications for diatom-based model predictions.

Keywords
Diatoms, limnological process timing, sediment trap, varve lake sediment, seasonal air temperature
National Category
Climate Research
Identifiers
urn:nbn:se:umu:diva-135326 (URN)
Available from: 2017-05-23 Created: 2017-05-23 Last updated: 2018-06-09
Maier, D. B.Using a decadal diatom sediment-trap record to unravel seasonal processes important for the formation of the sedimentary diatom signal.
Open this publication in new window or tab >>Using a decadal diatom sediment-trap record to unravel seasonal processes important for the formation of the sedimentary diatom signal
(English)Manuscript (preprint) (Other academic)
Abstract [en]

Sediment trap studies are of great importance to develop a deeper understanding of how environmental processes are influencing sediment deposition. We analyzed diatom assemblages from 2002 to 2015 in a sediment-trap record from a boreal lake (Nylandssjön, Sweden) together with environmental parameters, and compared the diatom record in the trap with the corresponding annually laminated sediments. In general, our data set indicates a large year-to-year variability of diatom succession and abundance patterns, which is well reflected in the varved sediments. The relative abundance of major taxa seems primarily controlled by seasonal characteristics, such as above-average winter air temperature and autumn runoff. Specifically, Cyclotella glomerata dominated the annual sediment trap record (and also the corresponding sediment varves) in years with warmer air temperatures in March-April, and Asterionella formosa dominated the annual sediment assemblages in years characterized by higher runoff before autumn lake over-turn. This study highlights that short-term environmental conditions and extreme events are of major importance for interpreting annual sediment signals.

Keywords
Diatoms, sediment trap, varved lake sediment, seasonal air temperature, discharge
National Category
Climate Research
Identifiers
urn:nbn:se:umu:diva-135329 (URN)
Available from: 2017-05-23 Created: 2017-05-23 Last updated: 2018-06-09
Organisations

Search in DiVA

Show all publications