A5102865015- Geology and Paleoclimatology Research
- Heavy metals in environment
- Isotope Analysis in Ecology
- Peatlands and Wetlands Ecology
- Mercury impact and mitigation studies
- Environmental DNA in Biodiversity Studies
- Climate change and permafrost
- Cryospheric studies and observations
- Microbial Community Ecology and Physiology
- Coastal wetland ecosystem dynamics
- Geochemistry and Geologic Mapping
- Marine and coastal ecosystems
- Geochemistry and Elemental Analysis
- Groundwater and Isotope Geochemistry
- Soil and Water Nutrient Dynamics
- Geological formations and processes
- Protist diversity and phylogeny
- Heavy Metal Exposure and Toxicity
- Pleistocene-Era Hominins and Archaeology
- Indigenous Studies and Ecology
- Social and Educational Sciences
- Archaeology and ancient environmental studies
- Hydrocarbon exploration and reservoir analysis
- Mine drainage and remediation techniques
- Aeolian processes and effects
Umeå University
2014-2025
University of South Dakota
2018
Technische Universität Braunschweig
2014-2016
Swedish University of Agricultural Sciences
2016
The use of lake sedimentary DNA to track the long-term changes in both terrestrial and aquatic biota is a rapidly advancing field paleoecological research. Although largely applied nowadays, knowledge gaps remain this there therefore still research be conducted ensure reliability signal. Building on most recent literature seven original case studies, we synthesize state-of-the-art analytical procedures for effective sampling, extraction, amplification, quantification and/or generation...
We used a collection of ten freeze cores annually laminated (varved) lake sediment from Nylandssjön in northern Sweden collected 1979 to 2007 follow the long‐term loss carbon (C) and nitrogen (N) due processes that occur bottom as ages. compared specific years different cores. For example, C surface varve core (sediment deposited during 1978) was followed 1980, 1985, 1989, so on until 2006. The concentration decreased by 20% N 30% within first five after deposition, 27 yr sediment, there 23%...
Using lake sediments to infer past total mercury and methylmercury loading the environment requires that diagenetic processes within sediment do not significantly affect concentrations or net accumulation rates of species. Because carbon is lost during early diagenesis, close link between raises question how reliable are as archives loading. In this study we used a series freeze cores taken in with varved (annually laminated) assess stability over time. By tracking material deposited...
To assess the long‐term (27 yr) effects of sediment aging on stable carbon and nitrogen isotope values (δ 13 C δ 15 N), we used a collection eight freeze cores annually laminated (varved) lake collected from 1979 to 2007 in Nylandssjon (northern Sweden). Previous research has shown that 20‐23% 35% is lost 27 yr. Material specific years was compared cores, e.g., N surface varve core followed retrieved 1980, 1989, 1993, 2002, 2004, 2006. increased by 0.4‐1.5% during first 5 After this initial...
Thawing of permafrost and a subsequent accelerated loss mercury from the soil constitute possible threat to quality high‐latitude surface waters. In this paper we estimate export generated by thawing palsa mire in northern Sweden, assessing net storage changes along thermokarst erosion gradients. Lower inventories inundated hummocks covered water (≤3.1 mg Hg m −2 ) than noneroding (between 5.5 8 suggests release ∼40–95% pool hummock peat experiencing subsidence submerging. The documented...
The climate in southern Patagonia is heavily influenced by the Southern Westerly Winds (SWW). Therefore, reconstructions from this region are valuable for our understanding of temporal dynamics atmospheric circulation Hemisphere. In study a sedimentary record shallow lake Laguna Amalia – located semiarid Fuegian steppe Tierra del Fuego (53°S) was used to how hydroclimate has changed over last ~7100 years. Our interpretations rely on combination pollen, diatoms, total organic carbon,...
Abstract Organic carbon (OC) burial rates in northern lakes are estimated to have increased by 2–3 fold over the past 150 years. However, assessing OC efficiency is challenging because (a) long‐term (decadal) process difficult study situ, and (b) sediment organic matter (OM) consists of thousands different compounds from both terrestrial aquatic sources, which subject degrees degradation, transformation, or preservation. Here, we used pyrolysis–gas chromatography/mass spectrometry track...
The analysis of environmental DNA (eDNA) from sediments has become an important method to study past ecosystem dynamics, offering new perspectives for paleoecological research. Yet, the temporal and spatial variability in sources transport pathways sediment remain underexplored. We studied how plant signal varies between annual lamina (or varves) Nylandssjön, a small boreal lake northern Sweden, 1991 2020. During this time period vegetation community composition catchment was stable...
Abstract Peatlands in northern latitudes sequester one third of the world’s soil organic carbon. Mineral dusts can affect primary productivity terrestrial systems through nutrient transport but this process has not yet been documented these peat-rich regions. Here we analysed and inorganic fractions an 8900-year-old sequence from Store Mosse (the “Great Bog”) southern Sweden. Between 5420 4550 cal yr BP, observe a seven-fold increase net peat-accumulation rates corresponding to maximum...
Abstract Chlorophyll is frequently used as a proxy for autochthonous production in lakes. This use of chlorophyll concentrations sediments to infer historical changes lake primary relies heavily on the assumption that preservation sufficient reflect productivity meaningful way. In this study, we series freeze cores from with annually laminated assess how reliable down-core trends are, and what extent degraded sediment. A striking consistency four sediment collected different years (1983,...
Abstract Detection of DNA in lake sediments holds promise as a tool to study processes like extinction, colonization, adaptation and evolutionary divergence. However, low concentrations make sediment difficult detect, leading high false negative rates. Additionally, contamination could potentially lead positive Careful laboratory procedures can reduce rates, but should not be assumed completely eliminate them. Therefore, methods are needed that identify potential results, use this...
The past decade has seen a rapid increase in interest the biogeochemical record preserved peat, particularly as it relates to carbon dynamics and environmental change. Importantly, recent studies show that dynamics, is, organic matter decomposition, can influence of atmospherically derived elements such halogens mercury. Most commonly, bulk density, light transmission, or carbon/nitrogen (C/N) ratios are used proxy qualitatively infer degree decomposition but do these three proxies reflect...
To assess the rates of compaction in recent, varved (annually laminated) lake sediments, we used a collection 13 freeze cores sampled from 1979 to 2012 Nylandssjön (northern Sweden). This unique series stored allowed us measure how thickness individual varves changed when they were overlain by new varves. The rate was greatest during first few years after deposition; varve decreased 60% 5 (sediment depth cm). Thereafter, declined, but 33 (the study period) there still weak trend continued 12...
Abstract. The composition of sediment organic matter (OM) exerts a strong control on biogeochemical processes in lakes, such as those involved the fate carbon, nutrients and trace metals. While between-lake spatial variability OM quality is increasingly investigated, we explored this study how molecular varies spatially within single lake related to physical parameters elemental geochemistry. Surface samples (0–10 cm) from 42 locations Härsvatten – small boreal forest with complex basin...
Abstract. Global warming is expected to be most pronounced in the Arctic where permafrost thaw and release of old carbon may provide an important feedback mechanism climate system. To better understand predict effects feedbacks on cycling elements within between ecosystems northern latitude landscapes, a thorough understanding processes related transport required. A fundamental requirement reach process have access high-quality empirical data chemical concentrations biotic properties for...