Refine
Has Fulltext
- no (2)
Document Type
- Article (2)
Language
- English (2)
Is part of the Bibliography
- yes (2)
Institute
- Institut für Geowissenschaften (2) (remove)
A submerged pine forest from the early Holocene in the Mecklenburg Lake District, northern Germany
(2018)
For the first time, evidence of a submerged pine forest from the early Holocene can be documented in a central European lake. Subaquatic tree stumps were discovered in Lake Giesenschlagsee at a depth of between 2 and 5m using scuba divers, side-scan sonar and a remotely operated vehicle. Several erect stumps, anchored to the ground by roots, represent an insitu record of this former forest. Botanical determination revealed the stumps to be Scots pine (Pinus sylvestris) with an individual tree age of about 80years. The trees could not be dated by means of dendrochronology, as they are older than the regional reference chronology for pine. Radiocarbon ages from the wood range from 10880 +/- 210 to 10370 +/- 130cal. a BP, which is equivalent to the mid-Preboreal to early Boreal biozones. The trees are rooted in sedge peat, which can be dated to this period as well, using pollen stratigraphical analysis. Tilting of the peat bed by 4m indicates subsidence of the ground due to local dead ice melting, causing the trees to become submerged and preserved for millennia. Together with recently detected Lateglacial insitu tree occurrences in nearby lakes, the submerged pine forest at Giesenschlagsee represents a new and highly promising type of geo-bio-archive for the wider region. Comparable insitu pine remnants occur at some terrestrial (buried setting) and marine (submerged setting) sites in northern central Europe and beyond, but they partly differ in age. In general, the insitu pine finds document shifts of the zonal boreal forest ecosystem during the late Quaternary.
Landscapes can be viewed as spatially heterogeneous areas encompassing terrestrial and aquatic domains. To date, most landscape carbon (C) fluxes have been estimated by accounting for terrestrial ecosystems, while aquatic ecosystems have been largely neglected. However, a robust assessment of C fluxes on the landscape scale requires the estimation of fluxes within and between both landscape components. Here, we compiled data from the literature on C fluxes across the air–water interface from various landscape components. We simulated C emissions and uptake for five different scenarios which represent a gradient of increasing spatial heterogeneity within a temperate young moraine landscape: (I) a homogeneous landscape with only cropland and large lakes; (II) separation of the terrestrial domain into cropland and forest; (III) further separation into cropland, forest, and grassland; (IV) additional division of the aquatic area into large lakes and peatlands; and (V) further separation of the aquatic area into large lakes, peatlands, running waters, and small water bodies These simulations suggest that C fluxes at the landscape scale might depend on spatial heterogeneity and landscape diversity, among other factors. When we consider spatial heterogeneity and diversity alone, small inland waters appear to play a pivotal and previously underestimated role in landscape greenhouse gas emissions that may be regarded as C hot spots. Approaches focusing on the landscape scale will also enable improved projections of ecosystems’ responses to perturbations, e.g., due to global change and anthropogenic activities, and evaluations of the specific role individual landscape components play in regional C fluxes. WIREs Water 2016, 3:601–617. doi: 10.1002/wat2.1147