不同生物质炭输入水平下旱作农田温室气体排放日变化研究

发布时间：2018-01-27 11:12

本文关键词： 旱作农田春小麦生物质炭温室气体排放通量日变化土壤温度土壤水分　出处：《中国生态农业学报》2016年10期 　论文类型：期刊论文

【摘要】：在陇中黄土高原干旱半干旱区,采用小区定位试验,对不同生物质炭水平(0 t·hm~(-2)、10 t·hm~(-2)、20 t·hm~(-2)、30 t·hm~(-2)、40 t·hm~(-2)、50 t·hm~(-2))下农田土壤温室气体(CO_2、N_2O和CH_4)的日排放通量及其影响因子进行连续观测,并确定1 d中不同生物质炭处理水平下的最佳观测时间。结果表明:6个生物质炭输入水平处理下,春小麦地土壤CH_4、N_2O和CO_2通量变化趋势与气温日变化轨迹大体一致,均表现为白天排放量大于夜间,并在4:00—5:00时,出现对CH_4通量的吸收峰,以及N_2O与CO_2的排放低谷;全天内各处理CH_4平均排放通量依次为:10.14mg·m~(-2)·h~(-1)、7.82mg·m~(-2)·h~(-1)、6.57mg·m~(-2)·h~(-1)、-0.10mg·m~(-2)·h~(-1)、1.05mg·m~(-2)·h~(-1)和2.89mg·m~(-2)·h~(-1),N_2O平均排放通量依次为:288.79mg·m~(-2)·h~(-1)、201.78mg·m~(-2)·h~(-1)、157.14mg·m~(-2)·h~(-1)、112.06mg·m~(-2)·h~(-1)、154.60mg·m~(-2)·h~(-1)和164.02mg·m~(-2)·h~(-1),CO_2平均排放通量依次为:85.44 mg·m~(-2)·h~(-1)、80.91 mg·m~(-2)·h~(-1)、76.49 mg·m~(-2)·h~(-1)、65.29 mg·m~(-2)·h~(-1)、67.19 mg·m~(-2)·h~(-1)和69.10 mg·m~(-2)·h~(-1);当生物质炭输入量小于30 t·hm~(-2)时,土壤CH_4、N_2O、CO_2排放通量随其输入量增加而显著减小,但当其输入量超过30 t·hm~(-2)时,3种温室气体排放通量则呈显著增大趋势;当生物质炭输入水平为30 t·hm~(-2)时,春小麦土壤全天表现为CH_4的吸收汇,其余各水平处理下的土壤表现为CH_4的弱排放源;6种处理水平下,全天春小麦地土壤表现为N_2O、CO_2的排放源。0~5 cm的土壤温度及水分(y)与生物质炭输入量(x)回归方程分别为y=-0.017 6x+16.585(R~2=0.302 6,r=-0.55,P0.05)和y=0.056 5x+13.626(R~2=0.815 1,r=0.903,P0.05),生物质炭输入量与0~5 cm的土壤水分呈显著正相关关系;无生物质炭输入处理下3种温室气体的吸收或排放通量与地表温度及5 cm地温均呈显著正相关关系,其他各处理也表现出不同程度的正相关关系。因此,当生物质炭输入水平为30 t·hm~(-2)时,更有利于CH_4、N_2O和CO_2 3种温室气体的增汇减排;生物质炭输入水平差异引起的土壤温度及水分差异可能是不同生物质炭处理CH_4、N_2O和CO_2日排放通量产生差异的主要原因;由矫正系数及最佳时段温室气体排放量与累积排放量回归分析可得,3种温室气体的最佳同期观测时间为8:00—9:00。
[Abstract]:In the arid and semi-arid region of the Loess Plateau in the middle of Gansu Province, the plot location test was used to study the different biomass carbon levels of 10 t 路hm-1 ~ (-2) ~ 10 t 路hm ~ (2) ~ (2) ~ 0 t 路hm ~ (-1) ~ (-1) ~ (-1). 20 t 路hm ~ (-1) -20 t 路hm ~ (2) ~ (30 t 路hm ~ (2)) ~ (40 t 路hm ~ (-2)) ~ (50 t 路hm ~ (-2))) soil greenhouse gas CO _ (2). The daily emission fluxes and their influencing factors of N2002 and CH4) were observed continuously. The best observation time was determined under different biomass carbon treatment level in 1 day. The results showed that the soil CH_4 of spring wheat field was treated with 6 biomass carbon input levels. The variation trend of N2O and CO_2 fluxes is roughly consistent with the diurnal variation of air temperature, which shows that the daytime emission is larger than that of night, and the absorption peak of CH_4 fluxes appears at 4: 00-5: 00. And the low emission of N2O and CO_2; During the whole day, the average emission fluxes of CH_4 in each treatment were: 1: 10.14 mg 路m-1). (6. 57 mg 路mA-1) 路hlang-1 (-0.10 mg 路mP-1) 路hm-1). (1. 05 mg 路mA-1) 路hnc-1) and 2. 89 mg 路mtb-1) 路hlang-1). The results were as follows: (1. 05 mg 路mA-1) and 2. 89 mg 路mP-1). The average emission fluxes of N2O were: 1 / 288.79mg 路mc-2) 路hnc-1 (201.78mg 路mc-2) 路hmb-1). The average emission fluxes of N2O were respectively: 1 / 288.79mg 路mc-2). 157.14 mg 路mA-1) 路hlang-1) 112.06 mg 路mPE-2) 路hm-1). 154.60 mg 路mA-1) and 164.02 mg 路mA-1) 路httrip-1). The average emission flux of CO_2 was 85.44 mg 路mAg-2) 路hlang-1), 80.91 mg 路mA-1) 路httrip-1), and the average flux of CO_2 was 85.44 mg 路mA-1). 76.49 mg 路mAg-2) 路hlang-1) 65.29 mg 路mAL-2) 路hlang-1). (67.19 mg 路mAg-2) 路hlang-1) and 69.10 mg 路mcaul-2) 路hlr-1; When the input amount of biomass carbon is less than 30 t 路hm ~ (-2), the emission flux of soil Ch _ 4 / N _ T _ 2O _ 2 / CO _ 2 decreases with the increase of the input amount. However, the emission fluxes of three kinds of greenhouse gases increased significantly when the input amount was over 30 t 路hm ~ (-2). When the input level of biomass carbon was 30 t 路hm ~ (-2), the soil of spring wheat showed the absorption sink of CH_4 throughout the day, and the soil under the other levels was a weak emission source of CH_4. N2O was found in the soil of spring wheat field under 6 treatments. The regression equations of soil temperature and water content of 5 cm of CO_2 emission source and biomass carbon input are y ~ (-0.017 ~ (6) x ~ (16.585)), respectively. RX2 + 0.302 6. (P 0.05) and Y (0.056 5x 13.626) (P 0.05) and 0.903U (0.903) (0.903) (P < 0.05), and 0.903 (0.903) (0.903) (P _ (0.05)). There was a significant positive correlation between biomass carbon input and soil moisture at 0 ~ 5 cm. The absorption or emission fluxes of three greenhouse gases were positively correlated with the surface temperature and 5 cm soil temperature under no biomass carbon input treatment, and the other treatments showed positive correlation in different degrees. When the input level of biomass carbon is 30 t 路hm ~ (-2), it is more favorable to increase and reduce the emission of three kinds of greenhouse gases: Ch _ 4 / N _ 2O and CO_2. The difference of soil temperature and moisture caused by the difference of biomass carbon input level may be the main reason for the difference of daily emission fluxes of CH4N _ 2O and CO_2 in different biomass carbon treatments. According to the regression analysis of greenhouse gas emissions and accumulative emissions in the correction coefficient and the optimum period, the best time of observation for the three greenhouse gases is 8: 00-9: 00.
【作者单位】：甘肃农业大学资源与环境学院;甘肃省干旱生境作物学重点实验室;甘肃省节水农业工程技术研究中心;安徽职业技术学院纺织服装学院;CSIR-Crops
【基金】：甘肃省干旱生境作物学重点实验室开放基金课题(GSCS-2012-13) 国家自然科学基金项目(31160269,31571594) “十二·五”《循环农业科技工程》项目(2012BAD14B03) 甘肃省自然科学基金项目(145RJZA204,145RJZA106)资助~~
【分类号】：X712
【正文快照】： **Corresponding author,E-mail:cailq@gsau.edu.cn5.CSIR-Crops Research Institute,P.O.BOX 3780-Kumasi,Ghana)Diurnal variations of greenhouse gases emissions under different biochar applications*SONG Min1,2,3,4,CAI Liqun1,2,3**,QI Peng1,2,3,Stephen Yeboah1,2

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