A response to 'Changes in water colour between 1986 and 2006 in the headwaters of the River Nidd, Yorkshire, UK: a critique of methodological approaches and measurement of burning management' by Yallop et al

摘要

Yallop et al. (2011) question the methodological approach we used to determine the proportion of managed burning occurring in fifteen sub-catchments of the River Nidd, north-east England and our conclusion that managed moorland burning has no effect either on water colour in streams draining these sub-catchments or on the increase in water colour that has occurred over a 20 year period. In response, we defend the approach we used to determine the proportion of heather burning in these sub-catchmentsand the conclusions we drew in Chapman et al. (2010). Firstly, we would like to clarify that the aim of our paper, as stated in the introduction, was not to investigate the impact of moorland burning on catchment scale drainage water colour, but to investigate changes in stream water colour over a 20 year period and whether the timing and/or magnitude of colour release were the same for all sub-catchments. The main findings of Chapman et al. (2010) were: (i) Water colour increased in all sub-catchments,but percent increase varied considerably between sub-catchments ranging from 22 to 155%. Statistical analysis revealed that the sub-catchments could be split into two 'Types' based on water chemistry and therefore dominant source of runoff.