Global Change Biology：中国畜禽粪便代替合成肥料对作物生产的影响的meta分析

中国农业大学资源与环境学院侯勇副教授团队利用143项研究结果对中国畜禽粪便替代化肥对作物产量等要素的影响进行了meta分析，相关成果发表于Global Change Biology（IF=8.88）。

Abstract

Recycling of livestock manure to agricultural land may reduce the use of synthetic fertilizer and thereby enhance the sustainability of food production. However, the effects of substitution of fertilizer by manure on crop yield, nitrogen use efficiency (NUE), and emissions of ammonia (NH₃), nitrous oxide (N₂O) and methane (CH₄) as function of soil and manure properties, experimental duration and application strategies have not been quantified systematically and convincingly yet. Here, we present a meta‐analysis of these effects using results of 143 published studies in China. Results indicate that the partial substitution of synthetic fertilizers by manure significantly increased the yield by 6.6% and 3.3% for upland crop and paddy rice, respectively, but full substitution significantly decreased yields (by 9.6% and 4.1%). The response of crop yields to manure substitution varied with soil pH and experimental durations, with relatively large positive responses in acidic soils and long‐term experiments. NUE increased significantly at a moderate ratio (<40%) of substitution. Ammonia emissions were significantly lower with full substitution (62‐77%), but not with partial substitution. Emissions of CH₄ from paddy rice significantly increased with substitution ratio, and varied by application rates and manure types, but N₂O emissions decreased. The substitution ratio did not significantly influence N₂O emissions from upland soils, and a relative scarcity of data on certain manure characteristic was found to hamper identification of the mechanisms. We derived overall mean N₂O emission factors (EF) of 0.56% and 0.17%, as well as NH₃ EFs of 11.1% and 6.5% for the manure N applied to upland and paddy soils, respectively. Our study shows that partial substitution of fertilizer by manure can increase crop yields, and decrease emissions of NH₃ and N₂O, but depending on site‐specific conditions. Manure addition to paddy rice soils is recommended only if abatement strategies for CH₄ emissions are also implemented.

将畜禽粪便循环利用到农田中，可以减少合成肥料的使用，从而提高粮食生产的可持续性。但不同土壤、肥料性质、试验持续时间和施用方式下畜禽粪便替代化肥对作物产量、氮素利用效率(NUE)以及氨(NH₃)、一氧化二氮(N₂O)和甲烷(CH₄)的排放的影响，尚未有系统和可靠的量化模型。本研究利用143项来自中国的研究结果对这些影响要素进行了meta分析。结果表明，畜禽粪便部分替代化肥将旱作作物和水稻产量显著提高了6.6%和3.3%，但完全替代化肥会使产量显著降低9.6%和4.1%。作物产量对肥料替代的响应随土壤pH值和试验时间的变化而变化，在酸性土壤和长期试验中表现出较大的正向响应。NUE在中等替代比例(<40%)下显著增加。完全替代(62%~77%)情况下氨的排放显著降低，部分替代则没有。水稻CH₄的排放随着替代比例的增加而显著增加，且随施肥量和肥料类型的不同而变化；N₂O的排放随替代比例增加而有所下降。替代比例对旱作土壤N₂O的排放没有显著影响；某些相关的肥料特性的数据相对缺乏，阻碍了影响机理的确定。施用于旱作土壤和水稻土壤的氮肥总平均N₂O排放因子（EF）分别为0.56%和0.17%，NH₃分别为11.1%和6.5%。研究结果表明，畜禽粪便部分替代化肥可以增加作物产量，减少NH₃和N₂O的排放，但也取决于具体的农田条件。建议仅在实施减少CH₄排放的战略时在水稻土壤中使用畜禽粪便代替化肥。