Plant identity control on soil food web structure and C transfers under perennial bioenergy plantations
Plant identity control on soil food web structure and C transfers under perennial bioenergy plantations
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DOI：
10.1016/j.soilbio.2019.107603
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发表时间：
2019-11
影响因子：
9.7
通讯作者：
M. Briones;D. Elias;H. Grant;N. McNamara
中科院分区：
文献类型：
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作者：
M. Briones;D. Elias;H. Grant;N. McNamara
为了满足市场能源需求，整个欧洲正在增加从可耕作种植制度向多年生生物能源作物的转变，但我们对这种土地利用变化如何影响地下多样性和碳分配的了解仍然有限。在这里，我们评估了英国生物能源商业种植园从耕地转变为杂草和短轮作科比斯(SRC)柳树对蚯蚓群落结构和丰度的影响。在同一地点，我们随后在两个生物能源种植园进行了现场13CO2脉冲追逐标记实验，以追踪最近光合作用同化的碳进入根、土壤、土壤微生物(PLFA)和蚯蚓群落的命运。结果表明，一年生作物改种为旱地和柳树两种多年生生物能源作物后，土壤蚯蚓丰度和生物量严重下降。与芒属相比，SRC柳树具有更高的微生物生物量，而芒属为功能更多样化的蚯蚓群落提供了更好的栖息地。在支持细菌捕食者在土壤食物链中的活动的情况下，不稳定的C化合物向土壤库的转移较快，而在SRC柳树人工林下，则以真菌驱动的碎屑分解过程为主。综上所述，这些发现表明，土地转化中的植物特性不仅对土壤群落的丰富度和结构有很大影响，而且还影响到哪些基础资源(根分泌物、死有机物或微生物衍生化合物)优先被消耗，并最终影响到这些不同碳库的动员速度。
Conversion from arable cropping systems to perennial bioenergy crops is increasing across Europe to meet market energy demands, but our understanding of how this land use change is affecting below-ground diversity and C allocation remains limited. Here, we assessed the impact of conversion from arable cropland toMiscanthusand Short Rotation Coppice (SRC) willow in UK bioenergy commercial plantations on earthworm community structure and abundance. At this same location we then conducted an in-situ13CO2pulse-chase labelling experiment in the two bioenergy plantations to trace the fate of recently photosynthetically assimilated carbon into roots, bulk soil, soil microbial (PLFA) and earthworm communities. Results showed that land conversion from annual arable crops to bothMiscanthusand SRC willow perennial bioenergy crops led to severe reductions of soil earthworm abundance and biomass. SRC willow had higher microbial biomass relative toMiscanthus, whereasMiscanthusprovided a better habitat for a more functionally diverse earthworm community. Transfer of labile C compounds to soil pools was faster underMiscanthus supporting activity of bacterial grazers in the soil food chain, whereas a fungal-driven detrital decomposition processes dominated under SRC willow plantations. Taken together, these findings indicate that plant identity in land conversions have a strong influence not only on the abundance and structure of soil communities but also on which basal resources (root exudates, dead organic matter or microbial derived compounds) are preferentially consumed, and ultimately on the rates of mobilisation of these different C pools.