A5070877222- Climate change and permafrost
- Cryospheric studies and observations
- Indigenous Studies and Ecology
- Peatlands and Wetlands Ecology
- Arctic and Antarctic ice dynamics
- Methane Hydrates and Related Phenomena
- Geology and Paleoclimatology Research
- Soil Moisture and Remote Sensing
- Species Distribution and Climate Change
- Geological Studies and Exploration
- Wildlife Ecology and Conservation
- Polar Research and Ecology
- Soil Geostatistics and Mapping
- Landslides and related hazards
- Remote Sensing and LiDAR Applications
- Coastal wetland ecosystem dynamics
- Isotope Analysis in Ecology
- Arctic and Russian Policy Studies
- Atmospheric and Environmental Gas Dynamics
- Ecology and Vegetation Dynamics Studies
- Soil and Unsaturated Flow
- Aquatic and Environmental Studies
- Tree-ring climate responses
- Agriculture, Soil, Plant Science
- Rangeland and Wildlife Management
Umeå University
2017-2024
Sofie Biosciences (United States)
2022
Abisko Scientific Research Station
2021
Stockholm University
2015-2018
Bolin Centre for Climate Research
2015-2017
University of Bonn
2012
Significance Over many millennia, northern peatlands have accumulated large amounts of carbon and nitrogen, thus cooling the global climate. shorter timescales, peatland disturbances can trigger losses peat release greenhouses gases. Despite their importance to climate, remain poorly mapped, vulnerability permafrost warming is uncertain. This study compiles over 7,000 field observations present a data-driven map nitrogen stocks. We use these maps model impact thaw on find that will likely...
Heterogeneous environmental controls on permafrost region soil organic carbon stocks can now be quantified with spatial modeling.
Snow is an important driver of ecosystem processes in cold biomes. accumulation determines ground temperature, light conditions, and moisture availability during winter. It also affects the growing season’s start end, plant access to nutrients. Here, we review current knowledge snow cover’s role for vegetation, plant-animal interactions, permafrost microbial processes, biogeochemical cycling. We compare studies natural gradients with experimental manipulation assess time scale difference...
Abstract Permafrost‐affected ecosystems are important components in the global carbon (C) cycle that, despite being vulnerable to disturbances under climate change, remain poorly understood. This study investigates ecosystem storage two contrasting continuous permafrost areas of NE and East Siberia. Detailed partitioning soil organic (SOC) phytomass (PC) is analyzed for one tundra (Kytalyk) taiga (Spasskaya Pad/Neleger) area. In total, 57 individual field sites (24 33 respective areas) have...
Abstract. Soil organic carbon (SOC) stored in northern peatlands and permafrost-affected soils are key components the global cycle. This article quantifies SOC stocks a sub-Arctic mountainous peatland environment discontinuous permafrost zone Abisko, Sweden. Four machine-learning techniques evaluated for quantification: multiple linear regression, artificial neural networks, support vector machine random forest. The forest model performed best was used to predict several depth increments at...
Tidal marshes store large amounts of organic carbon in their soils. Field data quantifying soil (SOC) stocks provide an important resource for researchers, natural managers, and policy-makers working towards the protection, restoration, valuation these ecosystems. We collated a global dataset tidal marsh (MarSOC) from 99 studies that includes location, depth, site name, dry bulk density, SOC, and/or matter (SOM). The MarSOC 17,454 points 2,329 unique locations, 29 countries. generated...
Abstract. Ponds and lakes are abundant in Arctic permafrost lowlands. They play an important role wetland ecosystems by regulating carbon, water, energy fluxes providing freshwater habitats. However, ponds, i.e., waterbodies with surface areas smaller than 1. 0 × 104 m2, have not been inventoried on global regional scales. The Permafrost Region Pond Lake (PeRL) database presents the results of a circum-Arctic effort to map ponds from modern (2002–2013) high-resolution aerial satellite...
Abstract Spatial analysis in earth sciences is often based on the concept of spatial autocorrelation, expressed by W. Tobler as first law geography: “everything related to everything else, but near things are more than distant things." Here, we show that subsurface soil properties permafrost tundra terrain exhibit tremendous variability. We describe variability organic carbon (SOC) and ground ice content from centimeter landscape scale three typical types common across Arctic region. At...
Abstract. Soils in the northern high latitudes are a key component global carbon cycle; permafrost region covers 22 % of Northern Hemisphere land surface area and holds almost twice as much atmosphere. Permafrost soil organic matter stocks represent an enormous long-term sink which is risk switching to net source future. Detailed knowledge about quantity mechanisms controlling storage utmost importance for our understanding potential impacts feedbacks on climate change. Here we present...
Permafrost thaw resulting from climate warming is threatening to release carbon high latitude peatlands. The aim of this research was determine subsidence rates linked permafrost in sub-Arctic peatlands Sweden using historical orthophotographic (orthophotos), Unoccupied Aerial Vehicle (UAV), and Interferometric Synthetic Aperture Radar (InSAR) data. orthophotos showed that the palsa on study sites have been contracting their areal extent, with greatest loss between 2002 2008. surface motion...
Abstract Plant biomass is a fundamental ecosystem attribute that sensitive to rapid climatic changes occurring in the Arctic. Nevertheless, measuring plant Arctic logistically challenging and resource intensive. Lack of accessible field data hinders efforts understand amount, composition, distribution, these northern ecosystems. Here, we present The aboveground synthesis dataset , which includes measurements lichen, bryophyte, herb, shrub, and/or tree (g m −2 ) on 2,327 sample plots from 636...
Abstract In the face of climate change, it is important to estimate changes in key ecosystem properties such as plant biomass and gross primary productivity (GPP). Ground truth estimates especially experiments are performed at small spatial scales (0.01–1 m 2 ) scaled up using coarse scale satellite remote sensing products. This will lead a scaling bias for non-linearly related heterogeneous environments when relationships not developed same We show that unmanned aerial vehicles (UAVs) can...
ABSTRACT Holocene rockwall retreat rates quantify integral values of rock slope erosion and talus cone evolution. Here we investigate exposed arctic sandstone cliffs in Longyeardalen, central Svalbard apply laboratory‐calibrated electrical resistivity tomography (ERT) to determine sediment thickness. Temperature–resistivity functions two samples are measured the laboratory compared with borehole temperatures from slope. The higher lower‐porosity at relevant permafrost defines a threshold...
Abstract. A new approach for the estimation of soil organic carbon (SOC) pools north tree line has been developed based on synthetic aperture radar (SAR; ENVISAT Advanced SAR Global Monitoring mode) data. SOC values are directly determined from backscatter instead upscaling using land cover or classes. The multi-mode capability allows application across scales. It can be shown that measurements in C band under frozen conditions represent vegetation and surface structure properties which...
The Ob River floodplain is the second largest in world. Despite its vast area, estimates of carbon (C) emissions from are largely absent. Here we present seasonal C emission and water area extent main channel along a ~4 km reach boreal zone River. We found strong seasonality (~1.8 km2) (~3 with covering 34% land during flood subsequently declining to ~16% ~14% summer autumn baseflow, respectively. also varied seasonally over open period, ranging −0.1 0.6 g m−2 d−1 for 0 9 floodplain....
Herbivory may offset climate change driven treeline expansion into the tundra. This study quantifies effects of reindeer grazing on mountain birch recruitment and growth in ecotone Scandinavian sub-arctic an area with contrasting regimes for past 20 years. We measured seedling density allometry trees below, at, above as well vegetation composition along transects crossing treeline. Additionally, we investigated nutrient loading soils its adult tree rate. Our results show that grazed winter...
Thawing permafrost increasingly threatens the integrity of legacy sites from resource exploration and extractive industries. In Northwest Territories, Canada, over 200 sumps containing drilling wastes within pose considerable environmental health risks to local ecosystems populations relying on land for subsistence. Exploratory activities have caused long-term disturbances terrains tundra vegetation, necessitating continued monitoring research. This study investigates complex interactions...
Permafrost peatlands undergo rapid changes in response to global warming. In this contribution, I will explore the role of remote sensing investigate these dynamics. UAV, historical orthophotos and satellite data can be used track permafrost peatlands. UAVs have proven return reliable spatial information with regular RGB imagery while at same time providing highly resolved 3D point-cloud digital terrain model data. Furthermore, multispectral sensors allow characterizing vegetation...