Meta分析湖南省双季稻田甲烷排放影响因素

李帅帅，张雄智，刘冰洋，赵 鑫，张海林

Meta分析湖南省双季稻田甲烷排放影响因素

李帅帅，张雄智，刘冰洋，赵 鑫，张海林※

（中国农业大学农学院，农业部农作制度重点实验室，北京 100193）

稻田是农业生产中甲烷的主要排放源。探索不同农田管理措施对甲烷排放的影响，对湖南省双季稻可持续生产意义重大。该研究利用Meta分析方法，基于该区域53篇公开发表研究文章中收集的840对数据研究发现：湖南省双季稻田中，双季稻甲烷排放占全年甲烷排放的97.9%，且晚稻甲烷排放显著大于早稻；冬闲期种植作物显著增加了双季稻田43.88%（< 0.05）的甲烷排放；免耕和复合种养（稻田养鸭、稻田养鱼等）则分别显著降低了双季稻26.84%、37.02%（< 0.05）的甲烷排放；另一方面，从单位产量甲烷排放来看，施氮肥显著降低了双季稻40.01%（< 0.05）排放量，这主要是由于水稻产量显著提高了73.87%（< 0.05）；施有机肥和秸秆还田显著增加稻田甲烷排放量，显著增加了68.11%、71.80%（< 0.05）的双季稻单位产量甲烷排放量。研究结果表明，在湖南双季稻生产中合理采用免耕、复合种养措施并合理化肥料投入等措施有利于平衡该区域水稻增产与甲烷减排。

甲烷；耕作；肥；双季稻田；Meta分析

0 引 言

全球气候变暖已经是科学界的共识，温室气体是气候变暖的主要原因。CH4是主要的温室气体之一，单位质量CH4综合增温效应在100a时间尺度上是CO2的28倍。大气中CH4含量显著增加，在2012年高达1.82×10-6，与工业革命前相比提高了约1.5倍[1]。据估算，在主要温室气体排放中约60%的CH4来自于农业生产[2]，稻田被认为是农业生产中CH4的主要排放源，其排放约占全球人为源CH4排放总量的11%[2]。水稻作为重要的粮食作物，关系到中国粮食安全问题。双季稻播种面积约占中国水稻总播种面积的40%[3]，对保障中国粮食安全、促进农民增收具有重要意义。湖南省作为典型的双季稻区，2015年和2016年湖南省双季稻播种面积均超过了水稻播种总面积的70%[3]。水稻种植过程中由于灌溉形成的淹水环境促进了CH4的产生与排放[4]。与单季稻相比，双季稻农田淹水时间超过1.5倍，从而排放了更多的甲烷[5]。此外，秸秆还田和施用有机肥，会提供大量产甲烷基质，使稻田CH4排放显著增加。因此，在全球气候变暖的趋势下，如何有效平衡减少温室气体排放与维持（或提高）水稻产量之间的关系，逐渐成为农业生产需要应对的重要挑战[6]。

农田管理措施会显著影响稻田CH4排放。在南方双季稻区，冬季种植绿肥并还田会给土壤带来大量的易分解有机质，为土壤产CH4菌提供更多的反应底物从而促进厌氧条件下CH4排放[7]。与传统耕作相比，免耕（尤其是长期免耕）能有效减少CH4排放。伍芬琳等通过在湖南双季稻田进行大田试验发现，与旋耕、翻耕相比，免耕显著减少早稻季、晚稻季CH4排放量[8]。Zhao等通过Meta分析的方法研究免耕对中国稻田甲烷排放的影响，结果显示与翻耕相比，免耕会降低约30%的CH4排放[9]­。由于良好的生态环境效应和市场对绿色安全稻米的需求，稻田养鸭、稻田养鱼、稻田养虾等复合种养模式在中国不断推广[10]。复合种养生态系统中，鸭子、鱼对水体的扰动加快了稻田土壤气体的交换，土壤氧化还原电位升高，减少了CH4的产生。此外，氮肥对CH4排放的影响存在争议，Shang等在湖南进行的长期肥料试验表明，施用氮肥会增加稻田CH4排放[11]，但Dong等研究发现在水稻土中添加氮肥，CH4排放量减少了38%～49％[12]。施用氮肥对CH4排放的影响机制复杂，主要会在植株-生态系统水平、微生物群落水平、生物化学水平3个层次上影响CH4排放，结果取决于这3个方面影响因素的相对强弱[13]。稻田施用有机肥提供了易分解有机碳作为产CH4底物，增加CH4排放[14]。

目前国内外对稻田CH4排放的研究一般通过大田试验研究某项农田管理措施对稻田温室气体排放的影响。由于各试验位点间土壤性质、气候条件等不同，试验结果往往存在差异。此外，目前的研究中特别缺乏从区域尺度或全国尺度系统揭示农田管理措施对稻田温室气体排放影响的研究。中国农业生产已经由单纯追求高产转为“高产、优质、高效、生态、安全”的绿色发展理念。在全球气候变暖的大背景下，稻田作为主要的CH4排放源，水稻生产中应该注重产量与温室气体的排放的平衡。本次研究以湖南省双季稻区为例，基于发表文献中的大田试验数据进Meta分析，探究农田管理措施对稻田甲烷排放的影响，为当地水稻生产中管理措施的改进提供可行性建议。

1 材料与方法

1.1 数据来源与筛选

本研究以“水稻或稻田”和“甲烷”为关键词分别在web of science和中国知网（CNKI）进行文献检索，收集筛选2018年以前经过同行评议发表的关于农田管理措施影响湖南双季稻田CH4排放的期刊论文。所选论文须为在中国湖南省开展的田间对比试验，不包含宏观评价类、综述类、室内培养及模型模拟类的论文。研究所利用的文献满足以下条件[15]：

1）水稻生育期CH4累积排放量直接给出，或者可通过CH4排放通量、水稻大田生育期等数据计算得到；

2）CH4测定方法为静态箱法，水稻全生育期进行CH4取样、测定；

3）论文中明确说明试验重复数，试验位点位于湖南省，并且论文提供了详细的试验位点；

4）论文中给出了不同处理、对照与其他农田管理措施（如耕作、施肥、灌溉等；或说明除处理、对照外其他农田管理措施相同）的细节。

经过筛选，最终获得论文53篇，可进行分析的试验数据840对（表1）。

表1 纳入Meta分析的文献的基础信息

1.2 数据处理与分析

在收集的文献中，若已提供稻田CH4排放量，则直接将其数据对用于分析；对于给出排放通量的，根据水稻生育期计算得到排放总量。对于以每hm2CO2当量（CO2-eq/hm2）表达排放量的，查看文章中材料与方法部分CH4增温潜势，将其除以25或28得到排放量[2]；另外，对于用CH4-C表达排放量的，以分子质量为转换因子即CH4除以系数12/16得到排放量。

本研究参考了Pittelkow等[67]的方法使用试验重复数计算得到权重。

通过Meta分析运算得到每对数据的效应值，计算权重加权平均后得到综合效应值。同时，利用Bootstrapping方法通过4 999次迭代计算其95%的置信区间。为了便于理解，通过式（3）计算得到CH4排放量的变化百分数

式中RC为处理组相对于对照组稻田CH4排放增加或者下降的百分比，%。

本文共对水稻产量、稻田CH4排放量、单位产量CH4排放量3个指标进行分析。其余指标效应值、变化百分数等的确定方法与CH4排放一致。

由于秸秆还田、氮肥施用情况等不同农田管理措施对稻田CH4排放影响不同。因此，对已有的数据进行分组，来检验某一特定农田管理措施对稻田CH4排放（表2）的影响，采用 Sigma Plot 12.0软件进行作图。

表2 农田管理措施对水稻产量及稻田CH4排放影响的数据分组

2 结果与分析

2.1 CH4排放占比情况

在收集到的53篇文献中，共有19对数据给出了冬闲期CH4排放量和周年CH4排放总量。通过计算平均值（表3），发现冬闲期CH4排放量仅占全年CH4排放总量的2.1%，稻田全年97.9%的CH4排放来自水稻生长季，其中早稻占38.01%，晚稻占59.89%，晚稻CH4排放显著大于早稻。

表3 早稻季、晚稻季和冬闲期CH4排放量及占全年CH4排放比例

2.2 农田管理措施对双季稻田CH4排放量的影响

2.2.1 稻作制度、复合种养及耕作方式对双季稻田CH4排放的影响

调整稻作制度，稻田冬季种植绿肥（黑麦草、紫云英）、油菜和马铃薯等会增加稻田CH4排放，免耕和复合种养（稻田养鸭、稻田养鱼等）会显著降低稻田CH4排放（图1）。稻田冬季种植绿肥并还田显著增加冬闲期稻田CH4排放量132.20%（< 0.05），显著增加双季稻CH4排放量43.88%（< 0.05）。对早稻CH4排放的促进作用显著大于晚稻，显著增加早稻CH4排放量76.46%（< 0.05），显著增加晚稻CH4排放量24.83%（< 0.05）。

与仅种植水稻相比，复合种养会显著减少双季稻CH4排放量37.02%（< 0.05）。其中显著减少早稻CH4排放量33.73%（< 0.05），显著减少晚稻CH4排放量30.99%（< 0.05）。与翻耕相比，免耕显著减少双季稻CH4排放量26.84%（< 0.05），其中显著减少早稻CH4排放量27.18%（< 0.05），显著减少晚稻CH4排放量21.39%（< 0.05）。

注：误差线表示95%置信区间。

Figure 1 Effects of crop rotation, symbiosis ecosystem and tillage methods on CH4emissions from double cropping rice fields

2.2.2 施氮肥、施有机肥及秸秆还田对双季稻田CH4排放的影响

施氮肥会显著降低稻田单位产量CH4排放量，主要是通过显著增加水稻产量而对稻田CH4排放量无明显影响来实现的（表4）。施氮肥会显著增加双季稻产量73.87%（< 0.05），导致双季稻单位产量CH4排放量显著减少40.01%（< 0.05）。分别增加早稻、晚稻产量103.44%、43.52%（< 0.05），最终降低早稻单位产量CH4排放量47.73%（< 0.05），晚稻单位产量CH4排放量17.24%（< 0.05）。

表4还表明，施有机肥和秸秆还田会显著增加稻田CH4排放量，对水稻产量无显著影响，因此会显著增加单位产量CH4排放量。施有机肥显著增加早稻、晚稻和双季稻CH4排放量79.44%、81.21%、73.37%（< 0.05），最终显著增加早稻、晚稻和双季稻单位产量CH4排放量69.22%、75.21%、68.11%（< 0.05）。秸秆还田显著增加早稻、晚稻和双季稻CH4排放量73.41%、119.78%、111.67%（< 0.05），最终显著增加早稻、晚稻和双季稻单位产量CH4排放量117.41%、108.21%、71.80%（< 0.05）。

%

表4 施肥及秸秆还田对双季稻产量及CH4排放的变化百分数的影响

3 讨 论

3.1 稻作制度、施有机肥及秸秆还田对稻田CH4排放的影响

冬季种植紫云英等绿肥作物并在早稻移栽前还田、施有机肥、秸秆还田都会促进CH4排放。三者原理相近，都提供了大量的易分解有机质作为产CH4底物。另一方面，淹水条件下有机物的快速分解加速稻田氧化还原电位（Eh）的下降，有利于产CH4菌生长和保持活性，从而促进稻田CH4排放[68-69]。

本研究得出绿肥还田会显著增加早稻CH4排放量76.46%（< 0.05），显著增加晚稻CH4排放量24.83%（< 0.05），对晚稻CH4排放的促进作用远远大于早稻。原因是早稻季绿肥刚翻埋还田，可以提供大量的易降解有机质。绿肥作物经过早稻季腐解，晚稻季虽然仍可继续提供易降解有机质，但数量已明显减少。这与朱波等[70]通过盆栽试验观测黑麦草翻埋还田对双季稻CH4排放影响的结果相近，试验观测到约60%的CH4排放来自早稻移栽前和早稻生长期。

3.2 施氮肥、耕作方式及复合种养对稻田CH4排放的影响

与不施氮肥相比，早稻季和晚稻季施氮并未观察到CH4排放存在显著差异。总体上，氮肥施用对稻田生态系统CH4排放的影响较少。陈冠雄等[71]研究结果表明尿素施用增加稻田CH4排放量。但Cai等[72]研究结果表明尿素施用降低了稻田CH4排放。施用铵态肥料会在3个方面对CH4排放产生影响：氮肥促进水稻根系发育，使根系分泌物增加，为CH4产生提供前体基质，从而促进CH4产生和排放；施用氮肥后，CH4氧化菌的生长和活性得到促进，CH4氧化加剧，从而减少CH4排放；NH4+与CH4具有相似的分子结构，竞争CH4氧化，从而促进CH4排放。尿素施用对稻田CH4排放的影响取决于这3个方面影响因素的相对强弱[13]。

免耕能够有效减少稻田CH4排放。一方面，免耕减少土壤扰动，增强土壤通气性，加强气体交换，降低土壤还原程度，不利于产CH4菌生长和保持活性，从而降低CH4的产生与排放[68-69]；另一方面，免耕条件下土壤的原有结构得到很好的保护，CH4氧化菌的生存环境得以维持，CH4的氧化加剧，CH4排放大量降低[73]。

采用稻田养鸭、稻田养鱼等复合种养模式能够显著减少稻田CH4排放。只有在严格厌氧条件下，产CH4菌才能保持活性，作用于产CH4基质产生CH4。在稻-鸭复合生态系统中，由于鸭子的活动，扰动水体，使稻田土壤中气体的交换加快，水中氧气含量增加；鸭子以田间浮游生物为食，减少了水体溶氧的消耗，土壤氧化还原电位升高，产CH4细菌数量减少活性减弱，减少了CH4的产生，土壤产生的CH4被较快地氧化，从而降低CH4的排放量[22]。

本研究选取湖南省作为典型的双季稻区进行研究，能够获取的大田试验数据较少。耕作措施、复合种养、稻作制度因产量数据较少未能对单位产量CH4排放量这一指标进行研究。灌溉方式会是影响CH4排放的重要因素，但由于在湖南省进行的灌溉试验较少，无法获取足够的数据对进行研究。

4 结 论

1）在湖南省双季稻田中，双季稻CH4排放占全年CH4排放大于90%，晚稻CH4排放显著大于早稻。

2）复合种养、免耕会影响厌氧环境的形成，降低CH4排放；冬季种植绿肥会通过提供大量产CH4基质促进CH4排放，对早稻季CH4排放的促进作用明显大于晚稻季。

3）施氮肥会显著增加水稻产量，对CH4排放无明显影响，因此显著降低单位产量CH4排放；施有机肥、秸秆还田会显著增加稻田CH4排放量，增加单位产量CH4排放。

4）免耕、复合种养和适量施氮肥可作为湖南省双季稻田有效的温室气体减排措施。

[1] Intergovernmental Panel on Climate Change(IPCC). Climate Change 2014-Mitigation of Climate Change. Contribution of Working Group III to the Fifth Assessment Report of the IPCC Synthesis report of the IPCC[M]. Cambridge: Cambridge University Press, 2014.

[2] Intergovernmental Panel on Climate Change (IPCC). Climate Change 2013-The Physical Science Basis Contribution of Working Group to the Fifth Assessment Report of the IPCC[M]. Cambridge: Cambridge University Press, 2013.

[3] 中国国家统计局. 年度分省数据[EB/OL]. (2017-02-28)[2018-10-21]. http: //data. stats. gov. cn/easyquery. htm?cn=E0103&zb=A0D0Q®=430000&sj=2016.

[4] Wassmann R, Lantin R S, Neue H U, et al. Characterization of methane emissions from rice fields in Asia. III. Mitigation options and future research needs[J]. Nutrient Cycling in Agroecosystems, 2000, 58(1/2/3): 23－36.

[5] Lu W F, Chen W, Duan B W, et al. Methane emissions and mitigation options in irrigated rice fields in southeast China[J]. Nutrient Cycling in Agroecosystems, 2000, 58(1/2/3): 65－73.

[6] Lal R. Sequestering carbon and increasing productivity by conservation agriculture[J]. Journal of Soil and Water Conservation, 2015, 70(3): 55－62.

[7] 唐海明，肖小平，孙继民，等. 种植不同冬季作物对稻田甲烷、氧化亚氮排放和土壤微生物的影响[J]. 生态环境学报，2014，23(5)：736－742. Tang Haiming, Xiao Xiaoping, Sun Jimin, et al. Effects of different winter covering crops cultivation on methane and nitrous oxide emission fluxes and soil microorganism in double-cropping paddy field[J]. Ecology and Environment Sciences, 2014, 23(5): 736－742. (in Chinese with English abstract)

[8] 伍芬琳，张海林，李琳，等. 保护性耕作下双季稻农田甲烷排放特征及温室效应[J]. 中国农业科学，2008，41(9)：2703－2709. Wu Fenlin, Zhang Hailin, Li Lin, et al. Characteristics of CH4emission and greenhouse effects in double paddy soil with conservation tillage[J]. Scientia Agricultura Sinica, 2008, 41(9): 2703－2709. (in Chinese with English abstract)

[9] Zhao Xin, Liu Shengli, Pu Chao, et al. Methane and nitrous oxide emissions under no-till farming in China: A meta-analysis[J]. Global Change Biology, 2016, 22(4): 1372－1384.

[10] 展茗，曹凑贵，汪金平，等. 复合稻田生态系统温室气体交换及其综合增温潜势[J]. 生态学报，2008，28(11)：5461－5468. Zhan Ming, Cao Cougui, Wang Jinping, et al. Green house gases exchange of integrated paddy yield and their comprehensive global warming potentials[J]. Acta Ecologica Sinica, 2008, 28(11): 5461－5468. (in Chinese with English abstract)

[11] Shang Qingyin, Yang Xiuxia, Gao Cuimin, et al. Net annual global warming potential and greenhouse gas intensity in chinese double rice-cropping systems: A 3-year field measurement in long-term fertilizer experiments[J]. Global Change Biology, 2011, 17(6): 2196－2210.

[12] Dong Haibo, Yao Zhisheng, Zheng Xunhua, et al. Effect of ammonium-based, non-sulfate fertilizers on CH4emissions from a paddy field with a typical Chinese water management regime[J]. Atmospheric Environment, 2011, 45(5): 1095－1101.

[13] Schimel Joshua. Rice, microbes and methane[J]. Nature, 2000, 403(6768): 375－377.

[14] 秦晓波，李玉娥，刘克樱，等. 长期施肥对湖南稻田甲烷排放的影响[J]. 中国农业气象，2006，42(1)：19－22. Qin Xiaobo, Li Yu'e, Liu Keying, et al. The effect of lone-term fertilization treatment on methane emission from rice fields in Hunan[J]. Chinese Journal of Agrometeorology, 2006, 42(1): 19－22. (in Chinese with English abstract)

[15] Gurevitch Jessica, Koricheva Julia, Nakagawa Shinichi, et al. Meta-analysis and the science of research synthesis[J]. Nature, 2018, 555(7695): 175－182.

[16] 白小琳，张海林，陈阜，等. 耕作措施对双季稻田CH4与N2O排放的影响[J]. 农业工程学报，2010，26(1)：282－289. Bai Xiaolin, Zhang Hailin, Chen Fu, et al. Tillage effects on CH4and N2O emission from double cropping paddy field[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2010, 26(1): 282－289. (in Chinese with English abstract)

[17] Zhang Hailin, Bai Xiaolin, Xue Jianfu, et al. Emissions of CH4and N2O under different tillage systems from double-cropped paddy fields in southern china[J]. Plos One, 2013, 8(6): e65277.

[18] 肖小平，伍芬琳，黄风球，等. 不同稻草还田方式对稻田温室气体排放影响研究[J]. 农业现代化研究，2007，28(5)：629－632. Xiao Xiaoping, Wu Fenlin, Huang Fengqiu, et al. Greenhouse air emission under different pattern of rice－straw returned to field in double rice area[J]. Research of Agricultural Modernization, 2007, 28(5): 629－632. (in Chinese with English abstract)

[19] Chen Zhongdu, Chen Fu, Zhang Hailin, et al. Effects of nitrogen application rates on net annual global warming potential and greenhouse gas intensity in double-rice cropping systems of the southern china[J]. Environmental Science and Pollution Research, 2016, 23(24): 24781－24795.

[20] Tang Haiming, Xiao Xiaoping, Wang Ke, et al. Methane and nitrous oxide emissions as affected by long-term fertilizer management from double-cropping paddy fields in southern china[J]. The Journal of Agricultural Science, 2016, 154(8): 1378－1391.

[21] 唐海明，肖小平，汤文光，等. 长期施肥对双季稻田甲烷排放和关键功能微生物的影响[J]. 生态学报，2017，37(22)：7668－7678. Tang Haiming, Xiao Xiaoping, Tang Wenguang, et al. Effects of long－term fertilizer treatments on CH4fluxes and key functional microorganisms in a double－cropping paddy field[J]. Acta Ecologica Sinica, 2017, 37(22): 7668－7678. (in Chinese with English abstract)

[22] 向平安，黄璜，甘德欣，等. 免耕稻－鸭生态种养技术的环境经济学分析[J]. 生态学报，2005，25(8)：1981－1986. Xiang Ping'an, Huang Huang, Gan Dexin, et al. An environmental economics analysis of a rice-duck ecological management technique with no－tillage[J]. Acta Ecologica Sinica, 2005, 25(8): 1981－1986. (in Chinese with English abstract)

[23] 甘德欣，黄璜，蒋廷杰，等. 免耕稻-鸭复合系统减少甲烷排放及其机理研究[J]. 农村生态环境，2005，21(2)：1－6. Gan Dexin, Huang Huang, Jiang Tingjie, et al. Decrease in CH4emission and its mechanism in no-tillage rice-duck complex system[J]. Journal of Ecology and Rural Environment, 2005, 21(2): 1－6. (in Chinese with English abstract)

[24] Ji Xionghui, Wu Jiamei, Peng Hua, et al. The effect of rice straw incorporation into paddy soil on carbon sequestration and emissions in the double cropping rice system[J]. Journal of the Science of Food and Agriculture, 2012, 92(5): 1038－1045.

[25] 吴家梅，纪雄辉，彭华，等. 南方双季稻田稻草还田的碳汇效应[J]. 应用生态学报，2011，22(12)：3196－3202. Wu Jiamei, Ji Xionghui, Peng Hua, et al. Carbon sequestration effects of rice straw return in double season paddy field in Southern China. [J]. Chinese Journal of Applied Ecology, 2011, 22(12): 3196－3202. (in Chinese with English abstract)

[26] 秦晓波，李玉娥，刘克樱，等. 不同施肥处理稻田甲烷和氧化亚氮排放特征[J]. 农业工程学报，2006，22(7)：143－148. Qin Xiaobo, Li Yu'e, Liu Keying, et al. Methane and nitrous oxide emission from paddy field under different fertilization treatments[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2006, 22(7): 143－148. (in Chinese with English abstract)

[27] 秦晓波，李玉娥，刘克樱，等. 不同施肥处理对稻田氧化亚氮排放的影响[J]. 中国农业气象，2006，27(4)：273－276.

Qin Xiaobo, Li Yu'e, Liu Keying, et al. Effects of different fertilization treatments on N2O emission from rice fields in Hunan Province[J]. Chinese Journal of Agrometeorology, 2006, 27(4): 273－276. (in Chinese with English abstract)

[28] 傅志强，黄璜，廖晓兰，等. 养鸭数量对CH4排放的影响[J].生态学报，2008，28(5)：2107－2114. Fu Zhiqiang, Huang Huang, Liao Xiaolan, et al. The effect of ducks on CH4emission from paddy soil: mechanism research in the rice-duck ecosystem[J]. Acta Ecologica Sinica, 2008, 28(5): 2107－2114. (in Chinese with English abstract)

[29] 王华，黄璜，杨志辉，等. 湿地稻－鸭复合生态系统综合效益研究[J]. 农村生态环境，2003，19(4)：23－26. Wang Hua, Huang Huang, Yang Zhihui, et al. Integrated benefits of paddy rice－duck complex ecosystem[J]. Rural Eco－Environment, 2003, 19(4): 23－26. (in Chinese with English abstract)

[30] 荣湘民，袁正平，胡瑞芝，等. 稻作制有机肥地下水位对稻田甲烷排放的影响[J]. 农业环境保护，2001，20(6)：394－397. Rong Xiangmin, Yuan Zhengping, Hu Ruizhi, et al. Effects of rice-based cropping system, organic manure and groundwater level on methane emission from rice fields[J]. Journal of Agro-Environment Science, 2001, 20(6): 394－397. (in Chinese with English abstract)

[31] 魏甲彬，周玲红，徐华勤，等. 南方种养结合模式对冬季稻田净碳交换和不同土层活性碳氮转化的影响[J]. 草业学报，2017，26(7)：138－146. Wei Jiabin, Zhou Linghong, Xu Huaqin, et al. Effects of forage planting and chickens on net carbon exchange and transformation of soil active carbon and nitrogen at different layers in paddy fields in South China in winter[J]. Acta Prataculturae Sinica, 2017, 26(7): 138－146. (in Chinese with English abstract)

[32] 周玲红，魏甲彬，成小琳，等. 南方冬季种养结合模式对双季稻田CH4和CO2排放的影响[J]. 生态与农村环境学报，2018，34(5)：433－440. Zhou Linghong, Wei Jiabin, Cheng Xiaolin, et al. Effects of winter green manure crops with and without chicken grazing on CH4and CO2emissions in a double－crop rice paddy field in South China[J]. Journal of Ecology and Rural Environment, 2018, 34(5): 433－440. (in Chinese with English abstract)

[33] Wang Cong, Shen Jianlin, Tang Hong, et al. Greenhouse gas emissions in response to straw incorporation, water management and their interaction in a paddy field in subtropical central china[J]. Archives of Agronomy and Soil Science, 2016, 63(2): 171－184.

[34] Yang X, Shang Q, Wu P, et al. Methane emissions from double rice agriculture under long-term fertilizing systems in Hunan, China[J]. Agriculture, Ecosystems & Environment, 2010, 137(3/4): 308－316.

[35] 李晶，王明星，陈德章. 水稻田甲烷的减排方法研究及评价[J]. 大气科学，1998，22(3)：99－107. Li Jing, Wang Mingxing, Chen Dezhang. Studies on mitigation methods of methane emission from rice paddies[J]. Chinese Journal of Atmospheric Sciences, 1998, 22(3): 99－107. (in Chinese with English abstract)

[36] Wu Xiaohong, Wang Wei, Xie Xiaoli, et al. Effects of rice straw mulching on N2O emissions and maize productivity in a rain-fed upland[J]. Environmental Science and Pollution Research, 2018, 25(7): 6407－6413.

[37] Wu Xiaohong, Wang Wei, Xie Xiaoli, et al. Response of N2O emission to straw retention under two contrasting paddy water conditions: A field experiment over rice–rice-fallow rotation[J]. Paddy and Water Environment, 2018, 16(1): 199－205.

[38] Wang Wei, Wu Xiaohong, Chen Anlei, et al. Mitigating effects of ex situ application of rice straw on CH4and N2O emissions from paddy-upland coexisting system[J]. Scientific Reports, 2016, 6(1):1－8.

[39] Tang Haiming, Xiao Xiaoping, Tang Wenguang, et al. Effects of winter covering crop residue incorporation on CH4and N2O emission from double-cropped paddy fields in southern china[J]. Environmental Science and Pollution Research, 2015, 22(16): 12689－12698.

[40] Tang Haiming, Xiao Xiaoping, Tang Wenguang, et al. Effects of winter cover crops straws incorporation on CH4and N2O emission from double-cropping paddy fields in southern china[J]. Plos One, 2014, 9(10): e108322.

[41] 唐海明，汤文光，帅细强，等. 不同冬季覆盖作物对稻田甲烷和氧化亚氮排放的影响[J]. 应用生态学报，2010，21(12)：3191－3199. Tang Haiming, Tang Wenguang, Shuai Xiqiang, et al. Effects of winter cover crop on methane and nitrous oxide emission from paddy field[J]. Chinese Journal of Applied Ecology, 2010, 21(12): 3191－3199. (in Chinese with English abstract)

[42] 唐海明，肖小平，帅细强，等. 双季稻田种植不同冬季作物对甲烷和氧化亚氮排放的影响[J]. 生态学报，2012，32(5)：1481－1489. Tang Haiming, Xiao Xiaoping, Shuai Xiqiang, et al. Effects of different winter covering crops cultivation on methane (CH4) and nitrous oxide (N2O) emission fluxes from double-cropping paddy field. [J]. Acta Ecologica Sinica, 2012, 32(5): 1481－1489. (in Chinese with English abstract)

[43] 唐海明，肖小平，汤文光，等. 双季稻区冬季覆盖作物残茬还田对稻田甲烷和氧化亚氮排放的影响[J]. 作物学报，2011，37(9)：1666－1675. Tang Haiming, Xiao Xiaoping, Tang Wenguang, et al. Effects of straw recycling of winter covering crop on methane and nitrous oxide emissions in paddy field[J]. Acta Agronomica Sinica, 2011, 37(9): 1666－1675. (in Chinese with English abstract)

[44] 彭华，纪雄辉，吴家梅，等. 生物黑炭还田对晚稻CH4和N2O综合减排影响研究[J]. 生态环境学报，2011，20(11)：1620－1625. Peng Hua, Ji Xionghui, Wu Jiamei, et al. Integrated effect of decreasing CH4and N2O emission by Biochar incorported to paddy field on late rice[J]. Ecology and Environmental Sciences, 2011, 20(11): 1620－1625. (in Chinese with English abstract)

[45] 彭华，纪雄辉，吴家梅，等. 不同稻草还田模式下双季稻田周年CH4排放特征及温室效应[J]. 农业环境科学学报，2015，34(3)：585－591. Peng Hua, Ji Xionghui, Wu Jiamei, et al. Annual CH4emission and greenhouse effects in double cropping rice fields with different rice straw returning methods[J]. Journal of Agro-Environment Science, 2015, 34(3): 585－591. (in Chinese with English abstract)

[46] 霍莲杰，纪雄辉，吴家梅，等. 有机肥施用对稻田甲烷排放的影响及模拟研究[J]. 农业环境科学学报，2013，32(10)：2084－2092. Huo Lianjie, Ji Xionghui, Wu Jiamei, et al. The effect of organic manures application on methane emission and its simulation in paddy fields[J]. Journal of Agro-Environment Science, 2013, 32(10): 2084－2092. (in Chinese with English abstract)

[47] 秦晓波，李玉娥，万运帆，等. 耕作方式和稻草还田对双季稻田CH4和N2O排放的影响[J]. 农业工程学报，2014，30(11)：216-224. Qin Xiaobo, Li Yu'e, Wan Yunfan, et al. Effect of tillage and rice residue return on CH4and N2O emission from double rice field.[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2014, 30(11): 216-224. (in Chinese with English abstract)

[48] 秦晓波，李玉娥，万运帆，等. 免耕条件下稻草还田方式对温室气体排放强度的影响[J]. 农业工程学报，2012，28(6)：210－216. Qin Xiaobo, Li Yu'e, Wan Yunfan, et al. Effects of straw mulching on greenhouse gas intensity under on-tillage conditions[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2012, 28(6): 210－216. (in Chinese with English abstract)

[49] 侯晓莉，李玉娥，万运帆，等. 不同稻秆处理方式下双季稻温室气体排放通量研究[J]. 中国环境科学，2012，32(5)：803－809. Hou Xiaoli, Li Yu'e, Wan Yunfan, et al. Greenhouse gases emission from paddy fields under different rice straw treatments[J]. China Environmental Science, 2012, 32(5): 803－809. (in Chinese with English abstract)

[50] 石生伟，李玉娥，李明德，等. 不同施肥处理下双季稻田CH4和N2O排放的全年观测研究[J]. 大气科学，2011，35(4)：707－720. Shi Shengwei, Li Yu'e, Li Mingde, et al. Annual CH4and N2O emissions from double rice cropping systems under various fertilizer regimes in Hunan province, China[J]. Chinese Journal of Atmospheric Sciences, 2011, 35(4): 707－720. (in Chinese with English abstract)

[51] 吴家梅，纪雄辉，霍莲杰，等. 稻田土壤氧化态有机碳组分变化及其与甲烷排放的关联性[J]. 生态学报，2013，33(15)：4599－4607. Wu Jiamei, Ji Xionghui, Huo Lianjie, et al. Fraction changes of oxidation organic carbon in paddy soil and its correlation with CH4emission fluxes[J]. Acta Ecologica Sinica, 2013, 33(15): 4599－4607. (in Chinese with English abstract)

[52] 吴家梅，纪雄辉，彭华，等. 不同种类有机肥施用对一季稻田CH4排放的影响[J]. 农业环境科学学报，2011，30(8)：1688－1694. Wu Jiamei, Ji Xionghui, Peng Hua, et al. The effect of different organic manures treatments on methane emission from single－cropping paddy fields[J]. Journal of Agro－Environment Science, 2011, 30(8): 1688－1694. (in Chinese with English abstract)

[53] 吴家梅，纪雄辉，彭华，等. 不同有机肥对稻田温室气体排放及产量的影响[J]. 农业工程学报，2018，34(4)：162－169. Wu Jiamei, Ji Xionghui, Peng Hua, et al. Effects of different organic fertilizers on greenhouse gas emissions and yield in paddy soils[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2018, 34(4): 162－169. (in Chinese with English abstract)

[54] 傅志强，龙攀，刘依依，等. 水氮组合模式对双季稻甲烷和氧化亚氮排放的影响[J]. 环境科学，2015，36(9)：3365－3372. Fu Zhiqiang, Long Pan, Liu Yiyi, et al. Effects of water and nitrogenous fertilizer coupling on CH4and N2O emission from double-season rice paddy field[J]. Environmental Science, 2015, 36(9): 3365－3372. (in Chinese with English abstract)

[55] 石生伟，李玉娥，万运帆，等. 不同氮、磷肥用量下双季稻田的CH4和N2O排放[J]. 环境科学，2011，32(7)：1899－1907. Shi Shengwei, Li Yu'e, Wan Yunfan, et al. Observation for CH4and N2O emissions under different rates of nitrogen and phosphate fertilization in double rice fields[J]. Environmental Science, 2011, 32(7): 1899－1907. (in Chinese with English abstract)

[56] 石生伟，李玉娥，秦晓波，等. 不同施肥处理对红壤晚稻田CH4排放的影响[J]. 生态与农村环境学报，2010，26(2)：103－108. Shi Shengwei, Li Yu'e, Qin Xiaobo, et al. CH4emission from late rice field of red clay soil under different fertilization treatments[J]. Journal of Ecology and Rural Environment, 2010, 26(2): 103－108. (in Chinese with English abstract)

[57] 石生伟，李玉娥，秦晓波，等. 晚稻期间秸秆还田对早稻田CH4和N2O排放以及产量的影响[J]. 土壤通报，2011，42(2)：336－341. Shi Shengwei, Li Yu'e, Qin Xiaobo, et al. Effect of rice straw incorporation of later rice season on CH4and N2O emission and grain yield from following early rice field[J]. Chinese Journal of Soil Science, 2011, 42(2): 336－341. (in Chinese with English abstract)

[58] Chen Dan, Wang Cong, Shen Jianlin, et al. Response of CH4emissions to straw and biochar applications in double-rice cropping systems: Insights from observations and modeling[J]. Environmental Pollution, 2018, 235: 95－103.

[59] Liu Jieyun, Shen Jianlin, Li Yong, et al. Effects of biochar amendment on the net greenhouse gas emission and greenhouse gas intensity in a Chinese double rice cropping system[J]. European Journal of Soil Biology, 2014, 65: 30－39.

[60] Shen Jianlin, Tang Hong, Liu Jieyun, et al. Contrasting effects of straw and straw-derived biochar amendments on greenhouse gas emissions within double rice cropping systems[J]. Agriculture, Ecosystems & Environment, 2014, 188: 264－274.

[61] Liu Yinglie, Zhou Ziqiang, Zhang Xiaoxu, et al. Net global warming potential and greenhouse gas intensity from the double rice system with integrated soil–crop system management: A three-year field study[J]. Atmospheric Environment, 2015, 116: 92－101.

[62] 李波，荣湘民，谢桂先，等. 有机无机肥配施条件下稻田系统温室气体交换及综合温室效应分析[J]. 水土保持学报，2013, 27(6)：298－304. Li Bo, Rong Xiangmin, Xie Guixian, et al. Effect of combined application of organic and inorganic fertilizers on greenhouse gases exchange and comprehensive global warming potential in paddy fields[J]. Journal of Soil and Water Conservation, 2013, 27(6): 298－304. (in Chinese with English abstract)

[63] 李波，荣湘民，谢桂先，等. 不同有机无机肥配施对双季稻田CH4排放的影响[J]. 生态环境学报，2013，22(2)：276－282. Li Bo, Rong Xiangmin, Xie Guixian, et al. Effect of combined application with organic and inorganic fertilizers on methane emission in double-cropping paddy fields[J]. Ecology and Environmental Sciences, 2013, 22(2): 276－282. (in Chinese with English abstract)

[64] 刘小燕，黄璜，杨治平，等. 稻鸭鱼共栖生态系统CH4排放规律研究[J]. 生态环境，2006，15(2)：265－269. Liu Xiaoyan, Huang Huang, Yang Zhiping, et al. Methane emission from rice-duck-fish complex ecosystem[J]. 2006, 15(2): 265－269. (in Chinese with English abstract)

[65] Xu Heshui, Zhu Bo, Liu Jingna, et al. Azolla planting reduces methane emission and nitrogen fertilizer application in double rice cropping system in southern china[J]. Agronomy for Sustainable Development, 2017, 37(4):1－9.

[66] Hedges Larry V, Gurevitch Jessica, Curtis Peter S. The meta-analysis of response ratios in experiment ecology[J]. Ecology, 1999, 80(4): 1150－1156.

[67] Pittelkow Cameron M, Linquist Bruce A, Lundy Mark E, et al. When does no-till yield more? A global meta-analysis[J]. Field Crops Research, 2015, 183: 156－168.

[68] 全孝飞，颜晓元，王书伟，等. 长期施用有机物料对稻田生态系统服务功能的影响[J]. 农业环境科学学报，2017，36(7)：1406－1415. Quan Xiaofei, Yan Xiaoyuan, Wang Shuwei, et al. Effects of long-term application of organic materials on the ecosystem services of paddy fields.[J]. Journal of Agro-Environment Science, 2017, 36(7): 1406－1415. (in Chinese with English abstract)

[69] Yan Xiaoyuan, Yagi Kazuyuki, Akiyama Hiroko, et al. Statistical analysis of the major variables controlling methane emission from rice fields[J]. Global Change Biology, 2005, 11(7): 1131－1141.

[70] 朱波，易丽霞，胡跃高，等. 黑麦草鲜草翻压还田对双季稻CH4与N2O排放的影响[J]. 农业工程学报，2011，27(12)：241－245. Zhu Bo, Yi Lixia, Hu Yuegao, et al. Effects of ryegrass incorporation on CH4and N2O emission from double rice paddy soil.[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2011, 27(12): 241－245. (in Chinese with English abstract)

[71] 陈冠雄，黄国宏，黄斌，等. 稻田CH4和N2O的排放及养萍和施肥的影响[J]. 应用生态学报，1995，6(4)：378－382. Chen Guanxiong, Huang Guohong, Huang Bin, et al. CH4and N2O emission from a rice field and effect of Azolla and fertilization on them[J]. Chinese Journal of Applied Ecology, 1995, 6(4): 378－382. (in Chinese with English abstract)

[72] Cai Zucong, Xing Guangxi, Yan Xiaoyuan, et al. Methane and nitrous oxide emissions from rice paddy fields as affected by nitrogen fertilisers and water management[J]. Plant and Soil, 1997, 196(1): 7－14.

[73] Zhao Xin, Pu Chao, Ma Shoutian, et al. Management-induced greenhouse gases emission mitigation in global rice production[J]. Science of The Total Environment, 2019, 649: 1299－1306.

Influencing factors of CH4emissions from double cropping paddy fields in Hunan Province, China based on Meta-analysis

Li Shuaishuai, Zhang Xiongzhi, Liu Bingyang, Zhao Xin, Zhang Hailin※

(,,,,100193,)

Warming climate has been a global concern. Methane is an important greenhouse gas. Double rice cropping system in Hunan province contributes a large proportion of the national rice production. In this study, we studied the effect of agricultural managements of rice on methane emissions from double cropping paddy fields in Hunan Province, China based on Meta-analysis method. Only studies designed as side-by-side paired field experiments were included in this study. Field management practices, treatments, and controls were described in detail in each study, and the location of the experiment was provided. If seasonal accumulative CH4emission fluxes were not directly provided, these values were calculated by multiplying time and mean CH4emissions by the measurement period. A total of 53 published peer-reviewed papers published before 2018were obtained by reference retrieval. From them, 840 groups of data were drawn. The management measures included crop rotation, symbiosis ecosystem, tillage, nitrogen fertilizer input, organic manure and residue retention. The control and treatment groups were fallow versus winter crops, paddy-rice system versus rice-duck and rice-fish systems, conventional versus no tillage, no fertilizer-N input versus fertilizer-N input, no manure input versus fertilizer-N and manure input, and fertilizer-N input versus residue retention. Natural log of response ratio was used as the effect size in the random effect meta-analysis. Results showed that CH4emissions from both early and late rice accounted for 97.9% of annual CH4emissions, and more CH4emissions from late rice was observed than that for early rice. In the double rice cropping system, adding winter crops could significantly increase CH4emissions from double rice season by 43.88% (< 0.05) compared to winter fallow. Moreover, the increase in methane emissions from early rice was significantly higher than that from late rice. Symbiosis ecosystem of rice (i.e., with ducks or fishes) and adopting no-till significantly decreased CH4emissions by 37.02% and 26.84% (< 0.05), respectively. The decrease in the emission from early rice field was much higher than that from late rice field. As for yield-scaled emission, application of N fertilizer decreased yield-scaled CH4emissions by 40.01% (< 0.05) mainly due to the yields increased by 73.87% (< 0.05). Additionally, organic fertilizer application and residue retention increased 68.11% and 71.80% (< 0.05) of yield-scaled CH4emissions without impacting the rice yield. The results suggested adopting symbiosis ecosystem rice production or no-till along with optimized N input is conducive to balancing rice yield and CH4emissions from fields with double rice cropping system in Hunan province.

methane; tillage; fertilizers; double cropping rice field; Meta-analysis

2018-12-24

2019-05-28

国家重点研发计划项目（2016YFD0300201）。

李帅帅，主要从事农田生态研究。Email：lishuaishuai3514@cau.edu.cn

张海林，博士，教授，主要从事保护性农业与农田生态研究。Email：hailin@cau.edu.cn

10.11975/j.issn.1002-6819.2019.12.015

Q178.51+6；S964.2

A

1002-6819(2019)-12-0124-09

李帅帅，张雄智，刘冰洋，赵 鑫，张海林. Meta分析湖南省双季稻田甲烷排放影响因素[J]. 农业工程学报，2019，35(12)：124－132. doi：10.11975/j.issn.1002-6819.2019.12.015 http://www.tcsae.org

Li Shuaishuai, Zhang Xiongzhi, Liu Bingyang, Zhao Xin, Zhang Hailin. Influencing factors of CH4emissions from double cropping paddy fields in Hunan Province, China based on Meta-analysis[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2019, 35(12): 124－132. (in Chinese with English abstract) doi：10.11975/j.issn.1002-6819.2019.12.015 http://www.tcsae.org