摘要
通过大田试验,在湖北省武穴市花桥镇设置不同再生稻栽培模式:常规人工插秧模式CK与2个机插秧优化栽培模式OM1、OM2,探究不同栽培模式下稻田甲烷(CH4)和氧化亚氮(N2O)排放、碳足迹以及净生态系统经济效益,为再生稻低碳丰产栽培提供理论依据。结果显示,栽培模式显著影响CH4排放,但对N2O排放影响不显著;OM2模式CH4周年累积排放量相比CK和OM1模式分别降低43.5%和26.3%;栽培模式显著影响水稻产量与碳足迹;与CK、OM1模式相比,OM2模式头季产量显著增加15.2%与5.8%;再生季产量显著提高44.2%和34.7%;优化模式OM2相对于CK与OM1显著降低了碳足迹,降幅分别为40.0%和24.0%;OM2模式净生态系统经济效益最高为20 768 CNY/h
农业生态系统是大气CH4和N2O的重要排放
再生稻是一种高效轻简化的栽培方
本研究于2020年10月至2021年10月进行,试验点位于湖北省黄冈市武穴市花桥镇郑公塔村(115°28′E,29°48′N),海拔为20.1 m,亚热带季风性湿润气候,年均温为18.6 ℃,年均降雨量为1 140.8 mm。水稻种植方式为移栽,供试水稻品种为丰两优香1号(Oryza sativa L.)。试验点土壤为泥沙田、潴育型水稻土,为第四纪红土沉积物发育,试验前土壤基本性状:有机碳 18.15 g/kg,全氮 1.33 g/kg,总磷为1.33 g/kg,总钾为3.23 g/kg,铵态氮 7.98 mg/kg,硝态氮 4.37 mg/kg,速效磷为9.85 mg/kg, 速效钾为85.35 mg/kg。
本试验采用完全随机区组设计,设常规栽培模式(CK)和2个优化栽培模式(OM1和OM2)。每个模式3次重复,小区面积为40
各模式均于3月底育秧,4月底进行移栽,CK为人工插秧,优化模式为机插秧,栽插行株距分别为30 、13 cm,每穴3株。各模式头季施肥量均为N 180 kg/h
对于CK,全生育期所需氮磷钾由尿素(46%)、过磷酸钙(12% P2O5)、氯化钾(60% K2O)提供,其中头季氮肥按基肥∶分蘖肥∶穗肥=5∶3∶2比例施用,磷、钾肥作为基肥一次性施用;对于再生季,在头季稻齐穗后15~20 d施用催芽肥,并于收割留桩后7 d结合复水施用促苗肥,氮磷钾施用量为催芽肥的一半。头季采用常规灌溉的水分管理方式,即苗期田间水位保持在3~5 cm,在分蘖盛期排水晒田1周以控制无效分蘖,之后复水保持水稻在3~5 cm,头季水稻收获前 10 d 排水晒干。对于再生季,头季稻收割留桩后7 d复水,保持浅水层3~5 cm,收获(8月23日)前1周排水晒干。
与CK 相比,OM1模式主要从肥料管理、水分灌溉、头季留茬高度等方面进行优化。OM1模式头季所需氮磷钾由缓释肥(15% N、7% P2O5、10% K2O,贵州天宝丰原生态农业科技有限公司,贵州贵阳)、过磷酸钙、氯化钾提供,且作为基肥一次性施入;再生季肥料施用与CK一致。OM1模式头季采用干湿交替灌溉方式。利用TEN90张力计(托普云农科技股份有限公司,浙江杭州)监测田间水势,在水稻移栽后田间水位保持在3~5 cm,水稻返青后,当田间水势达到-15 kPa时复水到3~5 cm,之后如此往复。而再生季采用与CK一样的浅水灌溉方式。头季稻收获后, OM1模式与CK一样,其再生季留茬高度为20 cm,且秸秆粉碎覆盖于稻桩之间。
OM2模式相对于CK主要从肥水管理、水分灌溉、头季秸秆处理、头季留茬高度、冬季绿肥种植等方面优化。OM2模式头季氮肥施用比例与CK一致,磷、钾肥作为基肥一次性施用;其中50%氮肥和全部的磷、钾肥通过半自动深施肥机(台州农乐塑料有限公司,浙江台州)作为基肥施入耕层10 cm,其余50%氮肥作为追肥表面撒施。OM2模式与OM1模式相同,其头季采用干湿交替灌溉方式,再生季采用浅水灌溉方式。头季稻收获后, OM2模式留茬高度为40 cm,其头季秸秆粉碎覆盖于稻桩之间,并喷施30 kg/h
1)温室气体。稻田温室气体CH4和N2O采用静态暗箱-气相色谱
F = ρ×h×dc/dt×273/(273+t) | (1) |
2)碳足迹。本研究分析不同再生稻栽培模式下作物从播种到收获整个生产过程中直接与间接的温室气体排放特征。直接温室气体排放为CH4和N2O排放。间接温室气体排放为冬季和稻季整年的农资投入(机械用柴油、种子、化肥、农膜、农药等)所产生,即每项农资产品从原材料的开采、运输、加工、制造所产生的温室气体排放总量。各项农资投入的间接排放引用了由亿科环境科技研发的包含中国本地化的生命周期基础数据库(Chinese life cycle database, CLCD)的生命周期评价软件 eBalance v3.1中的温室气体排放因子。本研究定义头季与再生季产生的稻谷为产品,定量评价不同再生稻栽培模式下每产生1 kg产品的碳足迹。具体单位产量碳足迹由公式(
CF= | (2) |
=+ | (3) |
= | (4) |
=×265+×28 | (5) |
式(
3)经济效益。经济效益为两季水稻产量收益减去生产成本。水稻产量的测定是在水稻成熟后选取4
净生态系统经济效益(net ecosystem economic benefit,NEEB)通过公式(
NEEB=水稻收益 - 生产成本 - GWP成本 | (6) |
GWP成本=GWP×碳价 | (7) |
式(
1)CH4排放通量变化。不同再生稻栽培模式冬季CH4排放通量为-0.11~0.33 mg/(

图1 不同再生稻栽培模式CH4排放通量的周年变化
Fig.1 Annual changes in CH4 emission fluxes under different cultivation modes of ratooning rice
2)N2O排放通量变化。各模式N2O排放通量冬季高于稻季,均在氮肥施用后出现峰值(

图2 不同再生稻栽培模式N2O排放通量的周年变化
Fig.2 Annual changes in N2O emission flux under different cultivation modes of ratooning rice
3)CH4和N2O累计排放量变化特征。栽培模式显著影响CH4的累计排放量,而对N2O的累计排放量的影响不显著(
模式 Modes | 冬季休闲 Winter fallow season | 头季 First rice season | 再生季 Ratooning rice season | 周年 Total | ||||
---|---|---|---|---|---|---|---|---|
CH4 | N2O | CH4 | N2O | CH4 | N2O | CH4 | N2O | |
CK | 8.1±1.9a | 2.06±0.52b | 235±13a | 1.30±0.53a | 65±13a | 0.72±0.11a | 308±28a | 4.08±0.76a |
OM1 | 9.4±1.1a | 1.96±0.49b | 175 ±11b | 1.12±0.38a | 51±11a | 0.56±0.05a | 236±10b | 3.64±0.64a |
OM2 | 6.1±1.5a | 3.40±0.59a | 111±16c | 0.95±0.58a | 58±13a | 0.59±0.11a | 174±29c | 4.94±0.49a |
注: 同列不同字母表示在5%水平上存在显著差异(P<0.05)。Note: Different letters in a row mean significant differences at the level of 5% (P<0.05).
如
农资投入Agricultural inputs | CK | OM1 | OM2 |
---|---|---|---|
柴油 Diesel fuel | 282.1 | 335.0 | 440.8 |
氮肥 N fertilizer | 534.7 | 482.0 | 596.7 |
磷肥 P fertilizer | 256.7 | 256.7 | 330.1 |
钾肥 K fertilizer | 185.3 | 185.3 | 214.5 |
有机肥 Organic fertilizer | 163.5 | 163.5 | |
除草剂 Herbicide | 23.6 | 19.1 | 30.1 |
杀虫剂 Herbicde | 23.0 | 23.0 | 23.0 |
杀菌剂 Fungicde | 12.7 | 12.7 | 12.7 |
农膜 Film | 136.3 | 22.7 | 22.7 |
秧盘 Tray | 454.4 | 454.4 | |
种子 Seed | 120.6 | 120.6 | 127.3 |
人工 Labor | 48.2 | 19.8 | 30.1 |
合计 Total | 1 623.2 | 2 094.6 | 2 445.7 |
各模式周年温室气体排放为8 611~11 329 kg CO2-eq /(h
项目 Items | CK | OM1 | OM2 |
---|---|---|---|
间接温室气体排放/( kg CO2-eq/(h Indirect greenhouse gas emissions | 1 623.2±0c | 2 094.6±0b | 2 445.7±0a |
CH4排放/( kg CO2-eq/(h CH4 emissions | 8 622±787a | 6 600±270b | 4 879±801c |
N2O排放/( kg CO2-eq/(h N2O emissions | 1 084±164a | 967±170a | 1 309±130a |
水稻产量/(kg/h Rice yield | 11 940±562c | 12 916±295b | 15 030±514a |
碳足迹/( kg CO2-eq/(h Carbon footprint | 0.95±0.09a | 0.75±0.04b | 0.57±0.05c |
注: 同行不同字母表示在5%水平上存在显著差异(P<0.05)。下同。Note: Different letters in a line mean significant differences at the level of 5% (P<0.05).The same as follows.
由
模式 Modes | 头季 First rice season | 再生季 Ratooning rice season | 周年 Annual |
---|---|---|---|
CK | 7 528±316b | 4 412±247b | 11 940±562c |
OM1 | 8 194±280 | 4 722±148b | 12 916±295b |
OM2 | 8 670±216a | 6 361±254a | 15 030±514a |
注: 同列不同字母表示在5%水平上存在显著差异(P<0.05)。Note:Different letters in the same row mean significant differences at the level of 5% (P<0.05).
由
模式 Modes | 产量收入 Rice income | 生产支出 Production costs | GWP 支出 | NEEB |
---|---|---|---|---|
CK | 29 849±1 405c |
14 381± 0c |
430± 41a | 15 038±1 410b |
OM1 | 32 289±737b |
15 750± 0b |
337± 21bc | 16 202±737b |
OM2 | 37 575±1 284 |
16 529± 0a |
277± 35c | 20 768±1 269a |
本研究结果表明,再生稻稻田CH4排放通量呈现明显季节性变化规律,稻季明显高于冬季,同时头季明显高于再生季(
本研究结果表明,OM2和OM1模式头季稻田CH4排放显著低于CK(
各模式N2O排放均在氮肥施用后产生峰值(
水稻生产投入的农资(化肥、农药、农膜和柴油等)被大量消耗亦会造成大量的碳排
本研究中各栽培模式碳足迹介于0.57~0.95 kg CO2-eq/(kg·a)。OM2模式碳足迹最小,OM1次之,CK最大(
本研究结果表明,优化模式头季稻产量显著高于常规模式(
NEEB是生产支出、增温潜势以及水稻产量的综合作用结
参考文献 References
叶兴庆,程郁,张玉梅,等.我国农业活动温室气体减排的情景模拟、主要路径及政策措施[J].农业经济问题,2022,43(2):4-16.YE X Q,CHENG Y,ZHANG Y M,et al.Scenario simulation,main paths and policy measures of greenhouse gas emission reduction of agricultural activities in China[J].Issues in agricultural economy,2022,43(2):4-16 (in Chinese with English abstract). [百度学术]
OITA A,SHIBATA H,SHINDO J.Nitrogen footprint:a novel indicator to quantify nitrogen loss to the environment[J].Journal of life cycle assessment(Japan),2018,14(2):120-133. [百度学术]
FANG K, HEIJUNGS R, DE SNOO G R.Theoretical exploration for the combination of the ecological,energy,carbon,and water footprints:overview of a footprint family[J].Ecological indicators,2014,36:508-518. [百度学术]
李成芳,胡红青,曹凑贵,等.中国再生稻田土壤培肥途径的研究与实践[J].湖北农业科学,2017,56(14):2666-2669,2721.LI C F,HU H Q,CAO C G,et al.Research and practice on improvement of ratoon rice soil fertility in China[J].Hubei agricultural sciences,2017,56(14):2666-2669,2721 (in Chinese with English abstract). [百度学术]
徐富贤, 袁驰, 王学春, 等. 不同杂交中稻品种在川南再生稻区的两季产量及头季稻米品质差异[J].中国生态农业学报(中英文),2020,28(7):990-998.XU F X, YUAN C, WANG X C, et al. Differences in the two-crop yields and main-crop rice qualities among different hybrid mid-season rice varieties in the ratooning rice region of southern Sichuan, China[J]. Chinese journal of eco-agriculture,2020,28(7): 990-998(in Chinese with English abstract). [百度学术]
王肖凤,汪吴凯,夏方招,等.水分管理对再生稻稻米品质的影响[J].华中农业大学学报,2021,40(2):103-111.WANG X F,WANG W K,XIA F Z,et al.Effects of water management on grain quality of ratooning rice[J].Journal of Huazhong Agricultural University,2021,40(2):103-111 (in Chinese with English abstract). [百度学术]
王兴,赵鑫,王钰乔,等.中国水稻生产的碳足迹分析[J].资源科学,2017,39(4):713-722.WANG X,ZHAO X,WANG Y Q,et al.Assessment of the carbon footprint of rice production in China[J].Resources science,2017,39(4):713-722 (in Chinese with English abstract). [百度学术]
张传红,韩露,谢佳男,等.江苏省主要农作物碳足迹动态及其构成研究[J].南京信息工程大学学报(自然科学版),2022,14(1):110-119.ZHANG C H,HAN L,XIE J N,et al.Carbon footprint dynamics and composition assessment of major crops production in Jiangsu Province[J].Journal of Nanjing University of Information Science & Technology (natural science edition),2022,14(1):110-119 (in Chinese with English abstract). [百度学术]
SUN M, ZHAN M, ZHAO M, et al. Maize and rice double cropping benefits carbon footprint and soil carbon budget in paddy field[J/OL]. Field crops research,2019, 243:107620[2022-06-16].https://doi.org/10.1016/j.fcr.2019.107620. [百度学术]
ZHANG Z S, GUO L J, LIU T Q, et al. Effects of tillage practices and straw returning methods on greenhouse gas emissions and net ecosystem economic budget in rice-wheat cropping systems in central China[J]. Atmospheric environment, 2015, 122 (2):636-644. [百度学术]
ZHENG X H,WANG M X,WANG Y S,et al.Comparison of manual and automatic methods for measurement of methane emission from rice paddy fields[J].Advances in atmospheric sciences,1998,15(4):569-579. [百度学术]
LI C F, ZHANG Z S, GUO L J, et al.Emissions of CH4 and CO2 from double rice cropping systems under varying tillage and seeding methods[J].Atmospheric environment,2013,80:438-444. [百度学术]
GAN Y T, LIANG C, WANG X Y,et al.Lowering carbon footprint of durum wheat by diversifying cropping systems[J].Field crops research,2011,122(3):199-206. [百度学术]
DUNFIELD P,KNOWLES R,DUMONT R,et al.Methane production and consumption in temperate and subarctic peat soils:response to temperature and pH[J].Soil biology and biochemistry,1993,25(3):321-326. [百度学术]
邓桥江,曹凑贵,李成芳.不同再生稻栽培模式对稻田温室气体排放和产量的影响[J].农业环境科学学报,2019,38(6):1373-1380.DENG Q J,CAO C G,LI C F.Effects of different ratooning cultivation modes on greenhouse gas emissions and grain yields in paddy fields[J].Journal of agro-environment science,2019,38(6):1373-1380 (in Chinese with English abstract). [百度学术]
SULTANA N,ZHAO J,ZHENG Y,et al.Stable isotope probing of active methane oxidizers in rice field soils from cold regions[J].Biology and fertility of soils,2019,55(3):243-250. [百度学术]
林文雄,陈鸿飞,张志兴,等.再生稻产量形成的生理生态特性与关键栽培技术的研究与展望[J].中国生态农业学报(中英文),2015,23(4):392-401.LIN W X,CHEN H F,ZHANG Z X,et al.Research and prospect on physio-ecological properties of ratoon rice yield formation and its key cultivation technology[J].Chinese journal of eco-agriculture,2015,23(4):392-401 (in Chinese with English abstract). [百度学术]
FAN D J,LIU T Q,SHENG F,et al.Nitrogen deep placement mitigates methane emissions by regulating methanogens and methanotrophs in no-tillage paddy fields[J].Biology and fertility of soils,2020,56(5):711-727. [百度学术]
LINQUIST B A,ADVIENTO-BORBE M A,PITTELKOW C M,et al.Fertilizer management practices and greenhouse gas emissions from rice systems:a quantitative review and analysis[J].Field crops research,2012,135:10-21. [百度学术]
SONG K F,ZHANG G B,YU H Y,et al.Methane and nitrous oxide emissions from a ratoon paddy field in Sichuan Province,China[J].European journal of soil science,2021,72(3):1478-1491. [百度学术]
IPCC. Climate change 2013:the physical science basis[M]. Cambridge and New York:Cambridge University Press, 2013. [百度学术]
LIU T Q, LI S H, GUO L G, et al. Advantages of nitrogen fertilizer deep placement in greenhouse gas emissions and net ecosystem economic benefits from no-tillage paddy fields[J/OL]. Journal of cleaner production, 2020:121322[2022-06-16].https://doi.org/10.1016/j.jclepro.2020.121322. [百度学术]
陈松文,刘天奇,曹凑贵,等.水稻生产碳中和现状及低碳稻作技术策略[J].华中农业大学学报,2021,40(3):3-12.CHEN S W,LIU T Q,CAO C G,et al.Situation of carbon neutrality in rice production and techniques for low-carbon rice farming[J].Journal of Huazhong Agricultural University,2021,40(3):3-12 (in Chinese with English abstract). [百度学术]
姜振辉, 杨旭, 刘益珍, 等. 春玉米-晚稻与早稻-晚稻种植模式碳足迹比较[J].生态学报,2019,39(21):8091-8099.JIANG Z H, YANG X, LIU Y Z, et al. Comparison of carbon footprint between spring maize-late rice and early rice-late rice cropping system[J].Acta ecologica sinica,2019,39(21):8091-8099(in Chinese with English abstract). [百度学术]
林志敏,李洲,翁佩莹,等.再生稻田温室气体排放特征及碳足迹[J].应用生态学报,2022,33(5):1340-1351.LIN Z M,LI Z,WENG P Y,et al.Field greenhouse gas emission characteristics and carbon footprint of ratoon rice[J].Chinese journal of applied ecology,2022,33(5):1340-1351 (in Chinese with English abstract). [百度学术]
XUE J F, PU C, LIU S L, et al. Carbon and nitrogen footprint of double rice production in Southern China.[J].Ecological indicators,2016,64:249-257. [百度学术]
ANSARI M A , CHOUDHURY B U, LAYEK B U, et al. Green manuring and crop residue management: effect on soil organic carbon stock, aggregation, and system productivity in the foothills of Eastern Himalaya (India)[J/OL]. Soil and tillage research,2022,218:105318[2022-06-16].https://doi.org/10.1016/j.still.2022.105318. [百度学术]
CHEN J N,ZHANG R C,CAO F B,et al.Critical yield factors for achieving high grain yield in early-season rice grown under mechanical transplanting conditions[J].Phyton,2020,89(4):1043-1057. [百度学术]
RAMASAMY S, BERGE H, PURUSHOTHAMAN S. Yield formation in rice in response to drainage and nitrogen application[J]. Field crops research,1997,51(1/2):65-82. [百度学术]
ZHANG H,XUE Y G,WANG Z Q,et al.An alternate wetting and moderate soil drying regime improves root and shoot growth in rice[J].Crop science,2009,49(6):2246-2260. [百度学术]
李桂花,张雪凌,周吉祥,等.长期秸秆还田下有机无机配施及微量元素和缓释肥的施用对双季稻产量和肥料利用率的影响[J].中国土壤与肥料,2021(6):149-155.LI G H,ZHANG X L,ZHOU J X,et al.Impact of manure incorporation,microelements and slow release fertilizer application on double rice yield and fertilizer use efficiency under long-term straw return condition[J].Soil and fertilizer sciences in China,2021(6):149-155 (in Chinese with English abstract). [百度学术]
CAO X C, YUAN L, LIU X X. Benefits of controlled-release/stable fertilizers plus biochar for rice grain yield and nitrogen utilization under alternating wet and dry irrigation[J/OL]. European journal of agronomy,2021,129:126338[2022-06-16].https://doi.org/10.1016/j.eja.2021.126338. [百度学术]
ZHAO C, HUANG H, QIAN Z H, et al. Effect of side deep placement of nitrogen on yield and nitrogen use efficiency of single season late japonica rice[J]. Journal of integrative agriculture, 2021,20(6):1487-1502. [百度学术]
高菊生,徐明岗,董春华,等.长期稻-稻-绿肥轮作对水稻产量及土壤肥力的影响[J].作物学报,2013,39(2):343-349.GAO J S,XU M G,DONG C H,et al.Effects of long-term rice-rice-green manure cropping rotation on rice yield and soil fertility[J].Acta agronomica sinica,2013,39(2):343-349 (in Chinese with English abstract). [百度学术]
胡启良,杨滨娟,刘宁,等.绿肥混播下不同施氮量对水稻产量、土壤碳氮和微生物群落的影响[J].华中农业大学学报,2022,41(6):16-26.HU Q L,YANG B J,LIU N,et al.Effects of application rates of nitrogen on rice yield, carbon and nitrogen, microbial community in soil under mixed sowing of green manure[J].Journal of Huazhong Agricultural University,2022,41(6):16-26(in Chinese with English abstract). [百度学术]
XU Y, LIANG L Q, WANG B R, et al. Conversion from double-season rice to ratoon rice paddy fields reduces carbon footprint and enhances net ecosystem economic benefit[J/OL]. The science of the total environment,2021,813:152550[2022-06-16].https://doi.org/10.1016/j.scitotenv.2021.152550. [百度学术]