Institute of Forest Science (INIA-CSIC), Crta. De La Coruña km 7.5, E-28040 Madrid, Spain; Sustainable Forest Management Group, University of Santiago De Compostela (USC), C/Benigno Ledo s/n, E-27002 Lugo, Spain.
Institute of Forest Science (INIA-CSIC), Crta. De La Coruña km 7.5, E-28040 Madrid, Spain.
J Environ Manage. 2023 Dec 1;347:119062. doi: 10.1016/j.jenvman.2023.119062. Epub 2023 Sep 30.
Poplar short rotation coppice (SRC) systems are important for biomass production and for short-to medium-term carbon (C) sequestration, contributing to a low-carbon bioeconomy and thus helping to mitigate global warming. The productivity and profitability of these plantations are, however, challenged under restrictive irrigation associated with climate change. This study compares the above- and below-ground C sequestration potential and economic viability of a 12-year plantation cycle (4 rotations of 3 years each) under Mediterranean conditions with optimum irrigation (T1) and 50% irrigation reduction (T2), analysing other promising biomass uses in the form of bioproducts. A total of 138 trees of the highly productive hybrid ('AF2') in a SRC-trial were sampled monthly (first rotation). Additionally, data from an extensive poplar plantation network (30 sites) was used to complete data for the plantation cycle. The average C content for above- and below-ground biomass was 17.04 Mg C ha yr (T1), falling by 24% in T2. The net present value (NPV) in T1 (6461 € ha) was 52% lower under T2 conditions. Extra payments for C sequestration increased the NPV to 8023 for T1 and 4331 € ha for T2. Roots represent an important C storage in the soil, accumulating 29.9 Mg C ha (T1) and 22.8 Mg C ha (T2) by the end of the cycle in our study. The mitigation potential is strongly fortified when the share of bioproducts in biomass end-use increases. Assuming a distribution of 50% bioenergy and 50% bioproducts, emission were reduced between -114 Mg CO ha (T1) and -88 Mg CO ha (T2) compared to BAU until end of the century. This scenario plays a crucial sink-effect role by storing C contained in biomass, which is not immediately released into the atmosphere.
杨树短轮伐期（SRC）系统对于生物质生产和短期到中期的碳（C）封存非常重要，有助于低碳生物经济，从而有助于缓解全球变暖。然而，在与气候变化相关的限制灌溉下，这些人工林的生产力和盈利能力受到挑战。本研究比较了在优化灌溉（T1）和 50%灌溉减少（T2）条件下，在 12 年种植周期（4 个 3 年的轮伐期）中，地中海条件下的地上和地下 C 封存潜力和经济可行性，并分析了以生物制品形式存在的其他有前途的生物质用途。在一个 SRC 试验中，总共对 138 棵高生产力杂交种（'AF2'）的树木进行了每月（第一轮）采样。此外，还利用了广泛的杨树种植网络（30 个地点）的数据来完成种植周期的数据。地上和地下生物量的平均 C 含量为 17.04 Mg C ha yr（T1），在 T2 下下降了 24%。在 T2 条件下，T1 的净现值（NPV）（6461 欧元 ha）降低了 52%。额外的 C 封存付款将 NPV 提高到 T1 为 8023 欧元 ha，T2 为 4331 欧元 ha。根系是土壤中重要的 C 储存库，在本研究结束时积累了 29.9 Mg C ha（T1）和 22.8 Mg C ha（T2）。当生物质最终用途中的生物制品份额增加时，缓解潜力会得到加强。假设生物能源和生物制品各占 50%，与 BAU 相比，到本世纪末，排放减少了-114 Mg CO ha（T1）至-88 Mg CO ha（T2）。在本研究中，这种情景通过储存生物质中包含的 C 发挥了至关重要的汇效应作用，这些 C 不会立即释放到大气中。
