Effects of biochar on organic nitrogen mineralization of

Effects of biochar on organic nitrogen mineralization of Northeast forest soil Reporter : Si. Yao Du First-graduate student Siyao Du , Jun Tao*, Xianxiang Luo , Yingjun Xu , Wei Gu Beijing Normal University, Academy of Disaster Reduction and Emergency Management 2016. 04. 22 , Vienna

Contents 1 Background 2 Materials&Methods 3 Results 4 Discussion 2

Background Forest soil excessive reclamation unreasonable land use Special physical and chemical properties of biochar Biochar added as a soil conditioner Soil degradation and lower fertility Biochar addition increases soil fertility and nutrient Effect soil organic nitrogen mineralization process 3

Background scholar results reason Priit Tammeorg Biochar reduces soil nitrogen mineralization Biochar promotes microbial fixation Dempster Biochar can inhibit the mineralization of organic nitrogen in the soil Reduces the amount of soil MBC Effects of biochar on organic nitrogen Controvertial! Kolb Biochar may promote the N mineralization The adsorption of mineralization of Northeastphenol forest soil compounds Angus Adding biochar did not change the mineralization of organic nitrogen De. Luca Adding biochar to forest soil can promote the nitrogen mineralization; Adding biochar to agricultural soil , the influence of the organic nitrogen mineralization is uncertain. 4

Materials&Methods 5

Materials&Methods Soil Forest soil from Harbin, Heilongjiang Province, China (0 -10 cm deep) Biochar Corn straw through slow pyrolysis at 550℃ Table 1. Chemical properties of the soil and biochar used in the experiment p. H Soil Biochar 6. 57 9. 34 TC(%) TN(%) NH 4+-N mg/kg 11. 19 1. 56 5. 91 68. 78 0. 67 - NO 3 --N mg/kg 38. 72 - Organic-N g/kg 9. 52 - Ash(%) 14. 53 6

Materials&Methods Experimental design Table 2. Experimental treatments Soil+1％BC 550 18℃ 30℃ CK(18℃) CK(30℃) BC 550(18℃) BC 550(30℃) p 40 g biochar-amended soil p Incubator (set temperature at 18℃ and 30℃) p Soil moisture was adjusted to 80% field capacity p Measure at 1, 3, 5, 11, 17 days in triplicate 7

Materials&Methods Experimental method Properties Method TC FLASH-2000 elemental analyzer TN FLASH-2000 elemental analyzer NO 3 --N phenol disulfonic acid using spectrophotometric methods NH 4+-N indophenol blue reagent using spectrophotometric methods Urease activities Spectrophotometer colorimetric method after incubation at 37ºC for 24 h Moisture content Gravimetry p. H-meter 8

Materials&Methods Calculation and statistical analysis Calculate with Excel software Draw with origin 8. 6 Analyse with SPSS 20. 0 Test with ANOVA (Duncan’s test) Evaluate the correlation with correlation analysis 9

Results 3. 1 NH 4+-N dynamics Trend of growth first 11 d decreased at 17 d Two biochar treatments are significantly lower Two 30℃ treatments are significantly higher 10

Results 3. 2 NO 3 --N dynamics Trend of growth Since 5 d, two biochar treatments are significantly lower Two 30℃ treatments are significantly higher 11

Results 3. 3 Net N mineralization dynamics Trend of growth Two biochar treatments are significantly lower Two 30℃ treatments are significantly higher 12

Results 3. 4 Net N mineralization rate dynamic Trend of growth Two biochar treatments are significantly lower Two 30℃ treatments are significantly higher 13

Results 3. 5 p. H dynamics Trend of decline Two biochar treatments are significantly higher Two 30℃ treatments are significantly lower 14

Results 3. 6 Soil urease activity dynamics Trend of growth Two biochar treatments are significantly lower two 30℃ treatments are significantly higher 15

Conclusion Ø Corn biochar significantly inhibits forest soil N mineralization Ø Forest soil organic nitrogen mineralization degree of two 30℃ treatments are significantly higher 16

Discussion Ø Biochar factor had more obvious effect on soil nitrogen mineralization Ø Biochar inhibits soil N mineralization by changing soil physicochemical properties, such as soil p. H, EC, and urease activities 17

Thanks for your attention! and thanks to: Jingjing Chang ; Xiao Wang ; He Zhang 18