Department of Soil Sciences, Research Institute of Organic Agriculture (FiBL), Ackerstrasse, CH-5070, Frick, Switzerland.
Organic Farming with focus on Sustainable Soil Use, Institute of Crop Science and Breeding II, Justus-Liebig University Giessen, 35394, Giessen, Germany.
Sci Rep. 2019 Feb 8;9(1):1702. doi: 10.1038/s41598-018-38207-w.
Agricultural practices contribute considerably to emissions of greenhouse gases. So far, knowledge on the impact of organic compared to non-organic farming on soil-derived nitrous oxide (NO) and methane (CH) emissions is limited. We investigated NO and CH fluxes with manual chambers during 571 days in a grass-clover- silage maize - green manure cropping sequence in the long-term field trial "DOK" in Switzerland. We compared two organic farming systems - biodynamic (BIODYN) and bioorganic (BIOORG) - with two non-organic systems - solely mineral fertilisation (CONMIN) and mixed farming including farmyard manure (CONFYM) - all reflecting Swiss farming practices-together with an unfertilised control (NOFERT). We observed a 40.2% reduction of NO emissions per hectare for organic compared to non-organic systems. In contrast to current knowledge, yield-scaled cumulated NO emissions under silage maize were similar between organic and non-organic systems. Cumulated on area scale we recorded under silage maize a modest CH uptake for BIODYN and CONMIN and high CH emissions for CONFYM. We found that, in addition to N input, quality properties such as pH, soil organic carbon and microbial biomass significantly affected NO emissions. This study showed that organic farming systems can be a viable measure contributing to greenhouse gas mitigation in the agricultural sector.
农业实践对温室气体排放有很大的贡献。到目前为止，关于有机农业与非有机农业对土壤衍生的一氧化二氮（NO）和甲烷（CH）排放影响的知识有限。我们在瑞士长期的“DOK”田间试验中，使用手动气室在 571 天内调查了草地三叶草青贮玉米-绿肥轮作中 NO 和 CH 的通量。我们比较了两种有机农业系统——生物动力学（BIODYN）和生物有机（BIOORG）——与两种非有机系统——仅矿物施肥（CONMIN）和包括厩肥的混合农业（CONFYM）——所有这些都反映了瑞士的农业实践，以及未施肥对照（NOFERT）。我们发现，与非有机系统相比，有机系统每公顷的 NO 排放量减少了 40.2%。与当前的知识相反，青贮玉米下的产量标准化累积 NO 排放量在有机和非有机系统之间相似。在青贮玉米下，我们在区域尺度上记录到 BIODYN 和 CONMIN 适度的 CH 吸收和 CONFYM 较高的 CH 排放。我们发现，除了 N 输入外，质量特性如 pH 值、土壤有机碳和微生物生物量对 NO 排放有显著影响。这项研究表明，有机农业系统可以成为减少农业部门温室气体排放的可行措施。
