Vytautas Magnus University, Studentų Str. 11, LT-53361 Akademija, Kaunas District, Lithuania.
Institute of Journalism and Communication, Chinese Academy of Social Sciences, Beijing 100732, China.
Sci Total Environ. 2020 Apr 20;714:136850. doi: 10.1016/j.scitotenv.2020.136850. Epub 2020 Jan 21.
The carbon footprint for organic and conventional crop farming systems was assessed in Kaunas district (Central Lithuania) using the Life Cycle Analysis (LCA). Data from field experiments were applied to define the effects of the organic and conventional crop farming systems. Both manure and mineral fertilizers were applied to the conventional and only manure in the organic rotations. The closed chamber method was employed to calculate carbon footprints of emitted and absorbed CO fluxes. The carbon flows in different agro-ecosystems were also analysed by the estimation of the biomass and leaf area index. The carbon footprints per hectare obtained for the organic farming systems were significantly lower than those obtained for the conventional ones. These results imply that the analysis of the whole crop rotation based on the LCA remains an important issue for analysis of the effects of farming. The introduction of ley and maize into the both organic (OF) and conventional farming (CF) systems resulted in the highest sank of C rates from the atmosphere that has been accumulated in highest net ecosystem production (NEP). The estimates of the carbon footprint indicate the capability of crops to sequester atmospheric carbon in biomass. Nonetheless, out of the crops considered, only ley featured the positive carbon balance and the lowest environmental impact due to the lowest CO emissions and LCA indices in both farming systems. The results imply that reasonable crop-mix within the crop rotation schemes may lead to reduction of CO emissions (i.e. their environmental impact) and mitigation of the climate change. However, the differences between the carbon footprint for the OF and CF agroecosystems were insignificant in general.
采用生命周期分析（LCA）方法，对立陶宛考纳斯地区（立陶宛中部）的有机和常规作物种植系统的碳足迹进行了评估。田间试验数据用于定义有机和常规作物种植系统的影响。常规种植系统中既施用了粪肥又施用了矿物肥料，而有机种植系统中仅施用了粪肥。采用密闭室法计算了排放和吸收 CO 通量的碳足迹。还通过估计生物质和叶面积指数来分析不同农业生态系统中的碳流。有机耕作系统的每公顷碳足迹明显低于常规耕作系统的碳足迹。这些结果表明，基于 LCA 对整个作物轮作的分析仍然是分析耕作影响的一个重要问题。在有机（OF）和常规耕作（CF）系统中引入休耕和玉米，导致从大气中吸收的 C 速率最高，在最高净生态系统生产（NEP）中积累。碳足迹的估计表明了作物在生物量中固存大气碳的能力。尽管如此，在所考虑的作物中，只有休耕由于在两个耕作系统中 CO 排放量最低和 LCA 指数最低，表现出正的碳平衡和最低的环境影响。这些结果表明，在作物轮作方案中合理的作物组合可能会减少 CO 排放（即其环境影响），并缓解气候变化。然而，一般来说，OF 和 CF 农业生态系统的碳足迹之间的差异并不显著。
