Insights into CO2 simulations from the Irish Blackwater peatland using ECOSSE model
Authors: Premrov Alina , Wilson David , Saunders Matthew , Yeluripati Jagadeesh , Renou-Wilson Florence 
Published: March 2020

&lt;p&gt;&lt;strong&gt;Abstract&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;Non-degraded peatlands are known to be important carbon sink; however, if they are exposed to anthropogenic changes they can act as carbon source. This study forms a part of the larger AUGER project (http://www.ucd.ie/auger). It uses the ECOSSE process-based model to predict CO&lt;sub&gt;2&lt;/sub&gt; emissions [heterotrophic respiration (Rh)] associated with different peatland management (Smith et al., 2010). The work aims to provide preliminary insights into CO&lt;sub&gt;2&lt;/sub&gt; modelling procedures for drained and rewetted sites from Blackwater, the former Irish raised bog. After drainage in 1950&amp;#8217;s (due to peat-extraction) and cessation of draining in 1999, the landscape developed drained &amp;#8216;Bare Peat&amp;#8217; (BP), and rewetted &amp;#8216;Reeds&amp;#8217; (R) and &amp;#8216;Sedges&amp;#8217; (S) sites (Renou-Wilson et al., 2019). Modelling of CO&lt;sub&gt;2&lt;/sub&gt; from these sites was done using ECOSSE-v.6.2b model (&amp;#8216;site-specific&amp;#8217; mode) with water-table (WT) module (Smith et al., 2010), and default peatland vegetation parameters. The other model-input parameters (including soil respiration, WT and other soil parameters) were obtained from measurements reported in Renou-Wilson et al. (2019). Simulations on drained BP site were run starting from 1950 and on rewetted R and S sites starting from 1999 (which is the year of cessation of drainage). The climate data inputs (2010-2017) were obtained from ICHEC (EPA_Climate-WRF, 2019). The long-term average climate data for model spin-up were obtained from Met &amp;#201;ireann (2012) with potential evapotranspiration estimated by Thornthwaite (1948) method. Daily ecosystem respiration (Reco) data for May/June 2011 to Aug 2011 obtained from raw CO&lt;sub&gt;2&lt;/sub&gt; flux measurements (Renou-Wilson et al., 2019) were used. For vegetated sites Rh was estimated from Reco using method explained in Abdalla et al. (2014). Daily CO&lt;sub&gt;2&lt;/sub&gt; simulations were compared to Reco for BP site (r&lt;sup&gt;2&lt;/sup&gt; =0.20) and to Rh for R site (r&lt;sup&gt;2&lt;/sup&gt; = 0.35) and S site (r&lt;sup&gt;2&lt;/sup&gt; = 0.55). The preliminary results showed some underestimation of simulated CO&lt;sub&gt;2 &lt;/sub&gt;indicating the need for further modelling refinements for satisfactory results. The results from BP site further indicated on the importance of including long-term drainage period (i.e. from 1950 on) because avoiding this step resulted in a large overestimation of predicted CO&lt;sub&gt;2&lt;/sub&gt;.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Acknowledgements&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;AUGER project is funded under the Irish EPA Research programme 2014-2020.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Literature&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;Abdalla, M., et al. 2014. Simulation of CO&lt;sub&gt;2&lt;/sub&gt; and attribution analysis at six European peatland sites using the ECOSSE Model. Water Air Soil Pollut 225:2182.&lt;/p&gt;&lt;p&gt;EPA_Climate-WRF (2019). ERDDAPv.1.82. ICHEC. https://erddap.ichec.ie/erddap/files/EPA_Climate/WRF/&lt;/p&gt;&lt;p&gt;Met &amp;#201;ireann. 2012. 30 year averages. Met &amp;#201;ireann - The Irish Meteorological Service, Ireland.&lt;/p&gt;&lt;p&gt;Renou-Wilson, F., et. al. 2019. Rewetting degraded peatlands for climate and biodiversity benefits: Results from two raised bogs. Ecol. Eng. 127:547-560.&lt;/p&gt;&lt;p&gt;Smith, J., et al. 2010. ECOSSE. User Manual.&lt;/p&gt;&lt;p&gt;Thornthwaite, C.W. 1948. An approach toward a rational classification of climate. Geog. Review 38, 55-94.&lt;/p&gt;