Identification, geo-hydromorphological assessment and the state of degradation of the southernmost blanket bogs in Europe

Blanket bogs are a globally rare type of ombrotrophic peatland internationally recognised for long-term terrestrial carbon storage, the potential to serve as carbon sinks and habitat provision. The majority of recognised areas of this habitat in Europe are found in the United Kingdom and Ireland, but the rarer examples found in Spain represent the southernmost continental edge-of-range. However, gaps in the peatland inventory suggest that a number of blanket bogs in the Cantabrian Mountains (northern Spain) are not recognised and are at increased threat of loss. This study identifies and provides geo-hydromorphological classification for 14 unrecorded blanket bogs and one protected blanket bog located between the administrative regions of Cantabria and Castilla y León. Peat depth surveys and carbon analysis of peat cores were used to determine the amount of carbon stored within the newly identified blanket bogs and the current rate, and drivers, of peatland degradation were examined using remote sensing techniques. A total extent of blanket bog covering 44.45 ha (>40 cm peat depth) containing more than 500,000 m3 of peat and an estimated 44.88 ± 3.31 kt C was mapped. Approximately 30.8% of the surface of blanket bogs examined was exposed peat, and even in the protected site, exposed peat surfaces are losing a minimum of 1.7 t C m-2 yr-1. The presence of livestock in unprotected sites is increasing the rate of erosion by over five times, and without protection exposed peat surfaces are releasing as much as 3.84 t C m-2 yr-1. The peatlands identified in this research extend the known limit of blanket bogs in Europe farther south than previously recorded and represent 10.5% of blanket bog currently recognised and protected in Spain. The range of anthropogenic pressures currently acting on peatlands in the Cantabrian Mountains, specifically livestock and windfarms, indicates that without protection these important landforms and stored carbon may be lost. An urgent update of European peatland inventories is thus required to preserve these valuable carbon stores and potential carbon sinks

Videographic Analysis of Eriophorum Vaginatum Spatial Coverage in an Ombotrophic Bog

The use of Remotely Piloted Aircraft Systems (RPAS) as well as newer automated unmanned aerial vehicles is becoming a standard method in remote sensing studies requiring high spatial resolution (<1 m) and very precise temporal data to capture phenological events. In this study we use a low cost rotorcraft to map Eriophorum vaginatum at Mer Bleue, an ombrotrophic bog located east of Ottawa, ON, Canada. We focus on E. vaginatum because this sedge plays an important role in methane (CH4) gas exchange in peatlands. Using the remote controlled rotorcraft we were able to record, process, and mosaic 11.1 hectares of 4.5 cm spatial resolution imagery extracted from individual frames of video recordings (post georegistration RMSE 4.90 ± 4.95 cm). Our results, based on a supervised classification (96% accuracy) of the red, green, blue image planes, indicate a total tussock cover of 2,417 m2. Because the basal area of the plant is more relevant for calculating its contribution to the CH4 flux, the tussock area was related to the basal area from field data (R2 = 0.88, p < 0.0001). Our final results indicate a total basal area of 1,786 ± 62.8 m2. Based on temporal measurements of CH4 flux from the peatland as a whole that vary over the growing season, we estimate the E. vaginatum contribution to range from 3.0% to 17.3% of that total. Overall, our low cost approach was an effective non-destructive way to derive E. vaginatum coverage and estimate CH4 exchange over the growing season