不同覆盖时期和覆盖方式对旱地冬小麦经济和环境效应的影响

doi:10.3864/j.issn.0578-1752.2021.03.014

摘要/Abstract

摘要：

【目的】明确不同覆盖时期（夏闲期和周年覆盖）以及不同覆盖方式（垄沟覆盖、全膜覆盖和秸秆覆盖）对旱地冬小麦产量、经济效益和温室气体排放的影响,为选择适合当地小麦生产的高产、高效和环境友好型覆盖措施提供科学依据。【方法】于2017—2019年2个小麦生长季在黄土高原典型旱作区陕西省永寿县开展大田试验,试验设6个处理,采用裂区设计。不同覆盖时期为主区,设置夏闲期覆盖和周年覆盖（生育期覆盖+夏闲期覆盖）2个处理,不同覆盖方式为副区,分别为垄膜沟秸秆全地面覆盖、全膜覆盖以及秸秆全地面覆盖3个处理。研究分析小麦产量、土壤蓄水量、生育期耗水量、水分利用效率、经济利润以及温室气体排放强度。【结果】与夏闲期覆盖相比,周年覆盖2季平均增产9.5%,周年秸秆覆盖平均产量较周年垄覆沟播处理高出622 kg·hm^-2,而与全膜穴播处理没有显著差异;周年覆盖生育期耗水量和水分利用效率较夏闲期覆盖分别提高5.6%和4.0%;周年覆盖可显著提高冬小麦经济效益,较夏闲期覆盖年平均净利润提高17.8%,周年覆盖中秸秆覆盖平均净利润>全膜穴播>垄覆沟播;同时,周年覆盖2季平均温室气体排放强度较夏闲期覆盖降低11.0%,差异达显著水平。其中,以周年秸秆覆盖的温室气体排放强度最低。【结论】与夏闲期覆盖相比,周年覆盖措施能够提高水分利用效率和生育期耗水量从而提高冬小麦产量和经济效益,同时减少温室气体排放强度。其中,周年秸秆覆盖措施具有较好的经济效益和最低的温室气体排放强度,适宜在黄土旱塬区冬小麦生产中推广应用。

关键词: 夏闲期覆盖, 周年覆盖, 旱地冬小麦, 产量, 经济效益, 温室气体排放强度

Abstract:

【Objective】 The objective of this study was to clarify the effects of different mulching periods (mulching during the summer fallow and the year-round mulching) and different mulching practices (ridge-furrow plastic mulching, whole field plastic mulching and straw mulching) on winter wheat yield, economic return and greenhouse gas emissions in dryland. 【Method】 The experiment was carried out from 2017 to 2019 in Yongshou Country, Shaanxi Province, which was a typical rainfed farming area of the Loess Plateau. The split plot design was employed with main plot of different mulching periods (mulching during the summer fallow and mulching over the year), and sub-plot of different mulching practices (ridge-furrow plastic mulching, whole field plastic mulching and straw mulching). Wheat yield, soil water storage and evapotranspiration during the winter wheat growing season and water use efficiency, economic profit and greenhouse gas emission intensity were analyzed. 【Result】 Compare to mulching practices during the summer fallow, the average yield of year-round mulching practices was increased by 9.5%. The average yield of annual straw mulching was 622 kg·hm^-2 higher than that of annual ridge-furrow plastic mulching, but there was no significant difference between the year-round straw mulching and year-round plastic film mulching. Compare to mulching practices during the summer fallow, the year-round mulching practices increased the evapotranspiration during the winter wheat growing season and water use efficiency by 5.6% and 4.0%, respectively. Compared to mulching practices during the summer fallow, the year-round mulching practices significantly increased the economic return of winter wheat by 17.8%, and the average net economic return was straw mulching>plastic film mulching>ridge-furrow plastic mulching among the year-round mulching practices. Moreover, compared to mulching practices during the summer fallow, the average greenhouse gas emission intensity of year-round mulching practices decreased of 11.0%, and the difference was significant. The lowest greenhouse gas emission intensity was in annual straw mulching. 【Conclusion】 Compared to mulching practices during the summer fallow, the year-round mulching practices could improve water use efficiency and evapotranspiration during the winter wheat growing season, thus improving the yield and economic returns of winter wheat, while reducing the intensity of greenhouse gas emissions. In all practices, the annual straw mulching had the best economic return and the lowest intensity of greenhouse gas emissions, which was suitable for popularization and application in dryland winter wheat production areas.

Key words: mulching during the summer fallow, the year-round mulching, dryland winter wheat, yield, economic return, the intensity of greenhouse gas emissions

毛安然,赵护兵,杨慧敏,王涛,陈秀文,梁文娟. 不同覆盖时期和覆盖方式对旱地冬小麦经济和环境效应的影响[J]. 中国农业科学, 2021, 54(3): 608-618.

MAO AnRan,ZHAO HuBing,YANG HuiMin,WANG Tao,CHEN XiuWen,LIANG WenJuan. Effects of Different Mulching Periods and Mulching Practices on Economic Return and Environment[J]. Scientia Agricultura Sinica, 2021, 54(3): 608-618.

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链接本文: https://www.chinaagrisci.com/CN/10.3864/j.issn.0578-1752.2021.03.014

https://www.chinaagrisci.com/CN/Y2021/V54/I3/608

图/表 6

图1

表1

田间试验设计"

主处理 Main plot	副处理 Subplot	收获后地表处理 Surface treatment after the harvest	播前 Before seeding	播种 Sowing
夏闲期 Summer fallow period	垄沟覆盖RM+FS	上季小麦收获后翻地起垄,垄上覆膜,沟内覆盖当季收获的秸秆,垄宽35 cm,沟宽30 cm The plot was plowed after the last wheat harvest, 35 cm-wide ridges and 30 cm-wide furrows were created, plastic mulch was placed on top of the ridge and wheat straw from the harvest crop was placed in the furrow	下季小麦播前移走覆盖物,施肥旋耕 The plastic film and wheat straw was manually removed from the plot before the next wheat seeding, after which the plot was applied basal fertilizer and plowed	常规平作,行宽20 cm Conventional flatten culture with 20 cm spacing between rows
	全膜覆盖 PM	上季小麦收获后翻地,地膜全地面覆盖,膜上覆土1 cm The plot was plowed after the last wheat harvest, the whole soil surface was mulched with plastic film and evenly covered with 1 cm of soil	下季小麦播前移走覆盖物,施肥旋耕 The plastic film was manually removed from the plot before the next wheat seeding, after which the plot was applied basal fertilizer and plowed	常规平作,行宽20 cm Conventional flatten culture with 20 cm spacing between rows
	秸秆覆盖 SM	麦秆全地面覆盖,覆盖量10 t·hm^-2 Wheat straw (10 t·hm^-2) was applied over the whole soil surface during the summer fallow	下季小麦播前移走覆盖物,施肥旋耕 The wheat straw was manually removed from the plot before the next wheat seeding, after which the plot was applied basal fertilizer and plowed	常规平作,行宽20 cm Conventional flatten culture with 20 cm spacing between rows
周年 Year- round	垄覆沟播 RM+FS	上季小麦收获后,沟内覆盖当季收获的秸秆,保留覆盖处理至夏闲期结束 Wheat straw from the harvest crop was placed in the furrow after the last wheat harvest and mulching treatment was retained until the end of the summer fallow	下季小麦播前移走覆盖物,施肥旋耕后起垄覆盖,垄宽35 cm,沟宽30 cm The plastic film and wheat straw was manually removed from the plot before seeding, after which the plot was applied basal fertilizer and plowed, 35 cm-wide ridges and 30 cm-wide furrows were created before the next wheat seeding. Plastic mulch is placed on top of the ridge	沟内种2行小麦,小麦行距20 cm,小麦行和地膜相距5 cm The wheat was manually planted in each furrow in two rows 20 cm spacing, ensuring that the wheat was 5 cm away from each ridge
	全膜穴播 PM	上季小麦收获后,保留覆盖处理至夏闲期结束 Mulching treatment was retained after the last wheat harvest until the end of the summer fallow	下季小麦播前移走覆盖物,施肥旋耕后地膜全地面覆盖,膜上覆土1 cm The plastic film was manually removed from the plot before the next wheat seeding, after which the plot was applied basal fertilizer and plowed, The whole soil surface was mulched with plastic film and evenly covered with 1 cm of soil	小麦行距20 cm,株距12 cm,每穴播10粒左右 The wheat was manually sown in shallow holes with 20 cm spacing between rows and 12 cm spacing within rows
	秸秆覆盖 SM	上季小麦收获后,保留覆盖处理至夏闲期结束 Mulching treatment was retained after the last wheat harvest until the end of the summer fallow	下季小麦播前移走覆盖物,施肥旋耕 The wheat straw was manually removed from the plot before the next wheat seeding, after which the plot was applied basal fertilizer and plowed	常规平作,行宽20 cm,播后麦草全地面覆盖,覆盖量10 t·hm^-2 Conventional flatten culture with 20 cm spacing between rows. Wheat straw (10 t·hm^-2) was applied after seeding

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年份 Year	覆盖时期 Mulching period	覆盖方式 Mulching practice	播前蓄水量 Soil water storage before seeding (mm)	收获后蓄水量 Soil water storage after the harvest (mm)	生育期总耗水 Evapotranspiration,ET (mm)	水分利用效率 Water use efficiency (kg·hm^-2·mm^-1)
2017—2018	夏闲期 Summer fallow period	RM+FS	388.45a	297.43a	395.22b	12.64a
		PM	438.28a	310.00a	432.47ab	12.04a
		SM	464.58a	310.78a	458.00a	13.25a
		均值Mean	430.44A	306.07A	428.56A	12.64A
	周年 Year-round	RM+FS	388.45a	316.96a	601.11a	12.87a
		PM	438.28a	301.31a	441.16b	10.66a
		SM	464.58a	295.17a	473.61b	10.74a
		均值Mean	430.44A	304.48A	505.30A	11.42A
2018—2019	夏闲期 Summer fallow period	RM+FS	483.92b	335.00a	294.82b	15.94a
		PM	497.87ab	335.86a	307.92ab	15.45a
		SM	521.52a	341.09a	326.33a	15.42a
		均值Mean	501.10A	337.31A	309.69A	15.60A
	周年 Year-round	RM+FS	497.37a	306.56a	336.71a	16.13a
		PM	504.38a	287.46a	362.82a	19.07a
		SM	527.82a	325.85a	347.87a	18.67a
		均值Mean	509.86A	306.62A	349.13A	17.96A
两年平均 Average	夏闲期 Summer fallow period	RM+FS	436.18b	316.21a	345.02b	14.29a
		PM	468.07ab	322.93a	370.19ab	13.75a
		SM	493.05a	325.94a	392.16a	14.34a
		均值Mean	465.77A	321.69A	369.13B	14.12B
	周年 Year-round	RM+FS	442.91b	311.76a	356.20b	14.50a
		PM	471.33ab	294.39a	401.99a	14.87a
		SM	496.20a	310.51a	410.74a	14.71a
		均值Mean	470.15A	305.55A	389.65A	14.69A