CREAF, Edifici C, Campus UAB, 08193 Cerdanyola del Vallès, Barcelona, Spain; ICTA, Edifici ICTA-ICP, Carrer de les Columnes s/n, Campus UAB, 08193 Cerdanyola del Vallès, Barcelona, Spain.
ICTA, Edifici ICTA-ICP, Carrer de les Columnes s/n, Campus UAB, 08193 Cerdanyola del Vallès, Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, 08010 Barcelona, Spain.
Sci Total Environ. 2019 Apr 10;660:1522-1532. doi: 10.1016/j.scitotenv.2019.01.101. Epub 2019 Jan 14.
Biochar is a high carbon material resulting from biomass pyrolysis that, when applied to croplands, can increase soil carbon and soil water retention. Both effects are of critical importance in semi-arid regions, where carbon decline and desertification are the main drivers of soil degradation. Since most environmental services provided by soil are mediated by belowground biota, effects of biochar on soil microbial and invertebrate communities must be evaluated under field conditions before its agricultural application can be recommended. We tested maize biochar for its mid-term effect on soil microbes and micro-arthropods of a Mediterranean vineyard. We applied biochar to three field plots with neutral sandy loam soils at a dose of 5 Mg ha. During two years, we monitored the abundance of functional groups of soil micro-arthropods and estimated the biomass of soil microbial groups. We also analyzed the δC value of microbial PLFA biomarkers to determine biochar-C utilization by each microbial group taking advantage of the δC natural abundance differences between the applied biochar and the soil. Biochar addition significantly reduced soil microbial biomass but did not alter the functional microbial diversity nor the abundance or biodiversity of soil micro-arthropods. The contribution of biochar-C to the diet of most microbial groups was very low through the monitoring period. However, two gram-negative bacterial groups increased their biochar-derived carbon uptake under extreme soil dryness, which suggests that biochar-C might help soil microbes to overcome the food shortage caused by drought. The decrease in microbial biomass observed in our experiment and the concomitant decrease of SOM mineralization could contribute to the carbon sequestration potential of Mediterranean soils after biochar addition.
生物炭是生物质热解产生的一种高碳物质，如果将其应用于农田，可以增加土壤中的碳含量并提高土壤的保水能力。这两种效果在半干旱地区都非常重要，因为在这些地区，碳衰减和沙漠化是土壤退化的主要驱动因素。由于土壤提供的大多数环境服务都受到地下生物群的调节，因此在推荐生物炭在农业中的应用之前，必须在田间条件下评估生物炭对土壤微生物和无脊椎动物群落的影响。我们测试了玉米生物炭对地中海葡萄园土壤微生物和小型节肢动物的中期影响。我们将生物炭以 5 Mg ha 的剂量应用于三个中性沙壤土的田间小区。在两年的时间里，我们监测了土壤小型节肢动物功能群的丰度，并估计了土壤微生物群的生物量。我们还分析了微生物 PLFA 生物标志物的 δC 值，以确定每个微生物群对施加生物炭的碳利用情况，利用施加的生物炭和土壤之间 δC 自然丰度的差异。生物炭的添加显著降低了土壤微生物生物量，但没有改变功能微生物多样性，也没有改变土壤小型节肢动物的丰度或生物多样性。在监测期间，生物炭-C 对大多数微生物群的饮食贡献非常低。然而，在极端土壤干燥条件下，两个革兰氏阴性细菌群增加了它们对生物炭衍生碳的吸收，这表明生物炭-C 可能有助于土壤微生物克服干旱引起的食物短缺。我们实验中观察到的微生物生物量减少以及 SOM 矿化的相应减少可能有助于生物炭添加后地中海土壤的碳封存潜力。
