CAJ | 학술논문

为揭示不同水平生物质炭输入对稻田土壤理化性质、水稻产量及温室气体排放的影响，采用自制竹炭在4种不同施用水平下（0、10、20、40 t/hm2）输入稻田土壤，开展了水稻一个生长周期的田间试验。结果表明，生物质炭输入可显著提高土壤pH值和有机碳含量（P<0.05），且有机碳含量增幅与生物质炭施用水平呈正比（相关系数为0.78，P<0.01）。生物质炭施用可显著降低土壤容重（P<0.05），最大降幅为0.25 g/cm3，土壤容重随着生物质炭施用量的增加而降低。不同处理水稻产量无显著性差异（P>0.05）。CH4累积排放量与生物质炭施用量呈负相关性（相关系数为-0.24，P<0.01），投加生物质炭可显著降低稻田CH4排放通量和累积排放量（P<0.05），但过量施用生物质炭（超过20 t/hm2）并不能显著降低CH4累积排放量（P>0.05）。相比对照处理（不输入生物质炭），生物质炭输入后一周内可显著性降低N2O排放通量（P<0.05），并在排水烤田时升高，最终稳定于9.80 mg/(m2·h)。生物质炭输入可显著性降低N2O累积排放量（P<0.05），但不同水平生物质炭输入处理之间差异不显著（P>0.05）。该试验条件下，生物质炭施用量为20 t/hm2时可实现稻田稳产和固碳减排目标，该研究可为太湖地区苕溪流域稻田增汇和温室气体减排提供参考。
위게시불동수평생물질탄수입대도전토양이화성질、수도산량급온실기체배방적영향，채용자제죽탄재4충불동시용수평하（0、10、20、40 t/hm2）수입도전토양，개전료수도일개생장주기적전간시험。결과표명，생물질탄수입가현저제고토양pH치화유궤탄함량（P<0.05），차유궤탄함량증폭여생물질탄시용수평정정비（상관계수위0.78，P<0.01）。생물질탄시용가현저강저토양용중（P<0.05），최대강폭위0.25 g/cm3，토양용중수착생물질탄시용량적증가이강저。불동처리수도산량무현저성차이（P>0.05）。CH4루적배방량여생물질탄시용량정부상관성（상관계수위-0.24，P<0.01），투가생물질탄가현저강저도전CH4배방통량화루적배방량（P<0.05），단과량시용생물질탄（초과20 t/hm2）병불능현저강저CH4루적배방량（P>0.05）。상비대조처리（불수입생물질탄），생물질탄수입후일주내가현저성강저N2O배방통량（P<0.05），병재배수고전시승고，최종은정우9.80 mg/(m2·h)。생물질탄수입가현저성강저N2O루적배방량（P<0.05），단불동수평생물질탄수입처리지간차이불현저（P>0.05）。해시험조건하，생물질탄시용량위20 t/hm2시가실현도전은산화고탄감배목표，해연구가위태호지구초계류역도전증회화온실기체감배제공삼고。
Biochar application to the paddy field may be an effective method to deal with global climate change for the mankind. The effect of four different application rates of biochar made from bamboo added to the paddy field on soil quality, rice yield and trace greenhouse gas emissions was investigated by a field experiment to provide a scientific basis for biochar agricultural application. The experiment was carried out in a rice farm from Tai Lake Region and consisted of four treatments, biochar at 10 t/hm2 (T1), biochar at 20 t/hm2 (T2), biochar at 40 t/hm2 (T3), and paddy field without biochar application as a control (T0). Each treatment had three replicates arranged in a completely randomized block design. Changes in soil chemical and physical properties, rice yield and trace greenhouse gases (CH4, N2O) emissions with biochar addition were investigated during a whole rice growing season of 2013. The results showed that, comparing with the control treatment, soil pH value and organic carbon content were significantly increased (P<0.05) after biochar application, and the increase of organic carbon content was proportional to biochar application amount (r=0.78, P<0.01). Soil bulk density was significantly decreased with the increasing biochar application rate (P<0.05). Biochar application had no significant effect on soil cation exchange capacity, total nitrogen, available phosphorus and quick-acting potassium content (P>0.05). Rice yields of four treatments were respectively (8 120.6±468.2), (8 313.5±221.8), (8 505.4±381.2) and (7 996.8±285.6) kg/hm2, and had no significant difference with biochar application amount (P>0.05), and the same result was obtained by the experiment of 2014, which showed biochar application cannot increase rice yield effectively, but can stable rice yield sustainably. CH4 emission flux decreased gradually with the increase of biochar application amount. Meanwhile, CH4 cumulative emission decreased effectively with biochar application. There was a negative correlation between CH4 cumulative emission and biochar application amount (r=-0.24, P<0.01).However, CH4 cumulative emission cannot decrease significantly by excessive biochar application (P>0.05). Comparing with the control (T0), N2O emission flux decreased significantly within a week after biochar application (P<0.05), and rose slightly during the drainage of the paddy field, and finally reached a steady value (about 9.80 mg/(m2·h)) for three biochar application treatments (T1, T2 and T3). However, there was no significant difference with CH4 cumulative emission between the treatments of biochar at 20 t/hm2 (T2) and 40 t/hm2 (T3) (P>0.05), implying that CH4 cumulative emission cannot decrease effectively by excessive biochar application (>20 t/hm2 for the purple clay soil in the Tai Lake region). N2O cumulative emission decreased significantly with biochar application (P<0.05), but there was no significant difference among the treatments with different biochar application rates (P>0.05). CH4 and N2O emission fluxes and cumulative emissions showed the similar changes according to the preliminary experiment results of 2014. In this experiment, considering the effect and cost comprehensively, biochar application amount at 20 t/hm2 could be a technical option to reach low carbon emission intensity and stable rice producitivity in the rice paddy agriculture. It also provided a viable way to realize the enhancement of carbon sequestration and the mitigation of greenhouse emissions in the Tiaoxi Watershed of Tai Lake region.