Falkland Island peatland development 1 processes and the pervasive presence of 2 fire 3 4

30 31 Palaeoecological analyses of Falkland Island peat profiles have largely been 32 confined to pollen analyses. In order to improve understanding of long-term Falkland 33 Island peat development processes, the plant macrofossil and stable isotope 34 stratigraphy of an 11,550 year Falkland Island Cortaderia pilosa (‘whitegrass’) peat 35 profile was investigated. The peatland developed into an acid, whitegrass peatland 36 via a poor fen stage. Macrofossil charcoal indicate that local fires have frequently 37 occurred throughout the development of the peatland. Raman spectroscopy analyses 38 indicate changes in the intensity of burning which are likely to be related to changes 39 in fuel types, abundance of fine fuels due to reduced evapotranspiration/higher 40 rainfall (under weaker Southern Westerly Winds), peat moisture and human 41 disturbance. Stable isotope and thermogravimetric analyses were used to identify a 42 period of enhanced decomposition of the peat matrices dating from ~7020 cal yr BP, 43 which possibly reflects increasing strength of the Southern Westerly winds. The 44 application of Raman spectroscopy and thermogravimetric analyses to the Falkland 45 Island peat profile identified changes in fire intensity and decomposition which were 46 not detectable using the techniques of macrofossil charcoal and plant macrofossil 47 analyses. 48 49