The performance of single - and multi - proxy transfer functions ( testate amoebae ,

26 Peatlands are widely exploited archives of palaeoenvironmental change. We developed and 27 compared multiple transfer functions to infer peatland depth to the water table (DWT) and pH 28 based on testate amoeba (percentages or presence/absence), bryophyte presence/absence and 29 vascular plant presence/absence data from sub-alpine peatlands in the SE Swiss Alps in order 30 to compare the performance of single-proxy vs. multi-proxy models and assess the 31 performance of presence/absence models. 32 Bootstrap cross-validation showed the best-performing single-proxy transfer functions for 33 both DWT and pH were those based on bryophytes. The best-performing TF overall were 34 those based on combined testate amoebae %, bryophytes and vascular plants for DWT and on 35 testate amoebae and bryophytes for pH. The comparison of DWT and pH inferred from TA % 36 and presence/absence models showed that the general patterns were similar but the magnitude 37 and timing of some shifts were different. 38 These results show new directions for palaeoenvironmental research suggesting: 1) that it is 39 possible to build transfer functions which perform well using presence/absence average data, 40 although with some loss of accuracy, 2) supporting the idea that multi-proxy inference models 41 may improve palaeoecological reconstruction. The performance of multi-proxy and single42 proxy transfer functions should be further compared in palaeoecological data. 43