Potential of biochar soil amendments to reduce N leaching in boreal field conditions estimated using the resin bag method

Kaltenburg-Lindau

2018

Sonderdruck

12667S

40000965

Addition of biochar to soil has been shown to reduce N leaching in pot experiments, but direct field measurements are scarce, and data is lacking especially from colder, boreal conditions. We measured the effect of biochar soil amendment on nitrate (NO3-) and ammonium (NH4+) leaching in field conditions using the resin bag method. Bags containing ion-exchange resins (6g of Amberlite, IR 120 (Na+- ion exchanger resin), and 6g Dowex 1x8 (Cl-- ion exchanger resin)) were placed under the plough layer (under ca. 20 cm deep intact soil columns that were cored out using a 10 cm diameter PVC tube, one resin bag per plot, n=3). In the summer 2017 resin bags were changed monthly between the end of May and beginning of September, extracted with 1 M NaCl and analyzed for inorganic N, to allow the comparison of N leaching in five different treatments at the PäästöSäästö project site (Soilfood Oy) in Parainen, SW of Finland.