Tytti Jussila, R. Heikkinen, S. Anttila, K. Aapala, M. Kervinen, J. Aalto, P. Vihervaara
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引用次数: 0
Abstract
Aapa mires are waterlogged northern peatland ecosystems characterized by a patterned surface structure where water‐filled depressions (‘flarks’) alternate with drier hummock strings. As one of the EU Habitat Directive priority habitats, aapa mires are important for biodiversity and carbon cycling, harbouring several red‐listed species and supporting unique species communities. Due to their sensitivity to hydrological disturbances, reliable, up‐to‐date and systematic information on the hydrological condition and responses of mires is crucial and required for multiple purposes ranging from carbon exchange modelling to EU Habitats Directive reporting and conservation and ecosystem restoration planning. Here, we demonstrate the usability of Sentinel‐2 satellite data in a semi‐automatic cloud‐based approach to retrieve large‐scale information on aapa mire hydrological variability. Two satellite‐derived metrics, soil moisture index and the extent of water‐saturated surfaces based on pixel‐wise classification, are used to quantify monthly and interannual wetness variation between 2017 and 2020 across Natura 2000 aapa mires in Finland, including responses to the extreme drought of 2018. The results revealed high temporal variability in wetness, particularly in the southern parts of the aapa mire zone and generally in the late summer months interannually. Observations from the drought summer showed that one third of usually year‐round wet flark surfaces may be exposed to drying during climatic extremes. Responses varied between sites and regions, implicating the significance of environmental factors for drought resistance: some sites maintained high levels of moisture, whereas others lost wet surfaces completely. Our study provides the first comprehensive national‐level representation of seasonal and interannual wetness variability and drought‐sensitivity of pristine aapa mire sites. The approach and methods used here can be directly upscaled outside protected areas and to other EU countries. Thus, they provide a means for harmonized, systematic large‐scale monitoring of this priority habitat, as well as valuable information for other applications supporting peatland conservation and research.
期刊介绍:
emote Sensing in Ecology and Conservation provides a forum for rapid, peer-reviewed publication of novel, multidisciplinary research at the interface between remote sensing science and ecology and conservation. The journal prioritizes findings that advance the scientific basis of ecology and conservation, promoting the development of remote-sensing based methods relevant to the management of land use and biological systems at all levels, from populations and species to ecosystems and biomes. The journal defines remote sensing in its broadest sense, including data acquisition by hand-held and fixed ground-based sensors, such as camera traps and acoustic recorders, and sensors on airplanes and satellites. The intended journal’s audience includes ecologists, conservation scientists, policy makers, managers of terrestrial and aquatic systems, remote sensing scientists, and students.
Remote Sensing in Ecology and Conservation is a fully open access journal from Wiley and the Zoological Society of London. Remote sensing has enormous potential as to provide information on the state of, and pressures on, biological diversity and ecosystem services, at multiple spatial and temporal scales. This new publication provides a forum for multidisciplinary research in remote sensing science, ecological research and conservation science.