Geo‐hydromorphological assessment of Europe's southernmost blanket bogs

Abstract

Blanket bogs are a globally rare type of ombrotrophic peatland internationally recognized for long‐term terrestrial carbon storage, the potential to serve as carbon sinks, habitat provision and for their palaeoenvironmental archive. This habitat is protected in the European Union under the Habitats Directive (92/43/EEC), but a number of blanket bogs located in the Cantabrian Mountains (northern Spain), representing the southernmost known edge‐of‐range for this habitat in Europe, are currently not recognized and are at increased threat of loss. Using climatic data, topography, aerial photography and peat depth surveys, this study has identified 10 new areas of blanket bog located between the administrative regions of Cantabria and Castilla y León. Peat depth data and topography were used to provide a detailed geomorphological description and hydromorphological classification (mesotope units) of these currently unrecognized areas of blanket bog. Maximum peat depth measured across the 10 sites ranged from 1.61 to 3.78 m, covering a total area of 18.6 ha of blanket bog (>40 cm peat depth). The volume of peat accumulated across the sites was determined to be more than 216 000 m3 and is estimated to hold 19.89 ± 3.51 kt C. Twenty‐four individual hydrological mesotope units were described, indicating a diverse assemblage of blanket bogs in this region. The peatlands identified in this research extend the known limit of blanket bogs in Europe farther south than previously recorded and – combined with four other unprotected blanket bogs recently identified in the Cantabrian Mountains – these peatlands represent 10.5% of blanket bog currently recognized and protected in Spain. The range of anthropogenic pressures currently acting on peatlands in the Cantabrian Mountains 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. © 2020 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd

The extent of windfarm infrastructures on recognised European blanket bogs

“…The lack of recognition and protection leaves blanket bog habitat exposed to different anthropogenic activities including windfarm developments. Clear examples of blanket bogs with irreversible damage have been already found and reported in Galicia 9 , and more recently in Cantabrian blanket bogs 22 .…”

“…In addition to Galician blanket bogs, a large number of potentially active blanket bogs (and therefore priority habitats) across the regional boundaries between Cantabria and Castilla y León 21,22 along the Cantabrian Mountain range remain unmapped and unprotected. These unmapped areas of blanket bog at the edge of the habitat's European range are, therefore, particularly at risk from windfarm developments, and may disappear before their extent and importance can be defined 5 .…”

“…When reporting the conservation status, a detailed understanding of the extent of this habitat is needed. However, several unrecognised blanket bogs have been described across the EU recently, highlighting the lack of understanding and consequently adequate protection of this important habitat 21,22 . In addition, some blanket bogs are recognised as special areas of interest and also included under Natura 2000, providing an additional legal protection for key habitats.…”

“…Current threats frequently included in Habitat Directive conservation status reports for blanket bogs are variable across Europe, although agriculture and livestock are the most common issues 25 . However, more recently, windfarm developments 3,6,22 have been highlighted as a concerning pressure for this habitat having impacts on peatland hydrology 6,22 , ground-level climatic conditions 7 and habitat biodiversity, contributing to vegetation changes and habitat transition 9 .…”

Aquatic carbon concentrations and fluxes in a degraded blanket peatland with piping and pipe outlet blocking

“…Recent research into blanket peatland degradation has examined landform structure (Chico et al, 2020), hydrological function (Holden et al, 2011), processes controlling gully erosion (Evans & Lindsay, 2010), the production, loss and fate of particulate organic carbon (POC) and dissolved organic carbon (DOC) in runoff (Li et al, 2019;Palmer et al, 2016;Pawson et al, 2012), and metal and nutrient pollution of watercourses (Gaffney et al, 2021;Rothwell et al, 2005). Recent work has also examined the impacts of restoration action such as exclusion of grazing (Valdeolivas et al, 2018), revegetation (González & Rochefort, 2018), ditch blocking, gully blocking and re-vegetation on runoff production (Shuttleworth et al, 2019), and DOC and POC concentrations and fluxes in stream water (Evans et al, 2016;Peacock et al, 2018;Renou-Wilson et al, 2019;Shuttleworth et al, 2015).…”