Meta分析有机肥施用对中国北方农田土壤CO2排放的影响

Meta-analysis on farmland soil CO2 emission in Northern China affected by organic fertilizer

为了探明中国北方地区不同气候类型、施肥措施、有机肥类型和试验年限下,有机肥施用(单施有机肥、有机无机肥配施)对生育期农田土壤CO2排放量的影响,该研究以不施肥、施用无机肥分别作为对照,根据已发表的相关田间试验数据,采用Meta分析方法,定量研究有机肥、有机肥配施无机肥对农田土壤CO2排放量的影响。结果表明:与不施肥、施用无机肥相比,有机肥施用总体上显著提高了农田土壤CO2排放量,分别提高了50.6%和36.3%;有机肥施用下,农田土壤CO2排放量依次减少的顺序为:单施有机肥、有机无机配施、无机肥+有机肥+缓释肥;采用有机肥+无机肥+缓释肥配施,土壤CO2排放量未显著增加;相比牛粪、猪粪和商品有机肥,鸡粪类有机肥对土壤CO2排放正效应最大;有机肥施用下,灰漠土农田土壤CO2排放量相对高;农田土壤CO2排放量与年均气温正相关,与年均降水量负相关。从环境的角度考虑,建议在中国北方采用无机肥+有机肥+缓释肥配施技术,不建议鸡粪大量施用及在灰漠土农田大量施用有机肥。该研究成果可为有机肥替代部分化肥在中国北方地区的推广应用提供参考。

This paper was aimed to investigate the effects of organic fertilizer application(single application of organic fertilizer and organic-inorganic fertilizer combination)on the CO2 emission in farmland soil during crop growth period,under different climate types,fertilization measures,organic fertilizer types and experiment years in Northern China.Non-fertilizer and inorganic fertilizer application were used as control treatments.Based on the published data of relevant experiment and the Meta-analysis method,the quantitative effects on application of organic fertilizer and organic-inorganic fertilizer combination on CO2 emission in farmland soil were studied.A total of 534 measurements were obtained including 89 pairs of data from 21 literatures.The experiments lasted from 1980 to 2017.The effects were determined by effect size by Meta-analysis method.The important factors affecting CO2 emission were selected by finding out those with important values higher than 0.8.The results showed that the organic fertilizer application significantly generally increased the CO2 emission in farmland soil than the non-fertilizer and inorganic fertilizer application,with an increment of 50.6%and 36.3%,respectively.No publication bias was found because the fail-safe number was far higher than the critical values by the fail-safe method.There was not significantly different among regions(P>0.05).Under the application of organic fertilizer,the CO2 emission of farmland soil decreased successively in the following order:single application of organic fertilizer,organic-inorganic fertilizer combination,and combined application of inorganic fertilizer,organic fertilizer and slow-release fertilizer.Soil CO2 emission did not significantly increase under the combined application of organic fertilizer,inorganic fertilizer and slow-release fertilizer.Compared with non-fertilizer,cow manure,pig manure and commercial organic manure,chicken manure had the greatest positive effects on soil CO2 emission.Under the application of organic fertilizer,the CO2 emission of farmland soil in gray desert was relatively high.The CO2 emission of farmland soil was positively correlated with the annual average temperature and negatively correlated with the annual average precipitation.The annual average temperature and annual average precipitation could explain about 11%-16%and 10%-12%change in effect size of CO2 emission,respectively.From the perspective of environment,it was suggested to apply the combined application of inorganic fertilizer,organic fertilizer and slow-release fertilizer in Northern China.Meanwhile,the chicken manure should not be applied in large quantities and organic fertilizer should not be used in grey desert farmland.The results of this study can provide valuable information for the popularization and application of organic fertilizer replacing partial chemical fertilizer in Northern China.