In-situ soil warming in Hopland, CA. LBNL_TES_SFA_Hopland

We investigated the microbial community responses to in situ warming at different soil depths in a Mediterranean grassland. The primary objective was to determine the if soil microbial activity increased and taxonomy changed with short-term warming across the soil profile. To this end we used Illumina sequencing of 16S ribosomal RNA and ITS2 genes to reveal the variations in microbial community composition and structure, determined carbon use efficiency and extracellular soil enzyme activity to assess microbial activity in organic and mineral soil horizons. Analysis showed that the microbial composition, diversity and abundance were resilient to higher (+4°C ambient) soil temperatures. Microbial activity and carbon use efficiency, on the other hand, increased with soil warming.

本研究针对地中海草原中不同土壤深度的原位增温（in situ warming）场景，探究了微生物群落的响应规律。本研究的核心目标为明确：在整个土壤剖面（soil profile）范围内，短期增温是否会提升土壤微生物活性并改变微生物分类学组成。为此，本研究通过对16S核糖体RNA（16S ribosomal RNA）与ITS2基因开展Illumina测序，解析了微生物群落组成与结构的变化；同时测定碳利用效率与胞外土壤酶活性，以评估有机土壤层与矿质土壤层中的微生物活性。分析结果表明，微生物群落的组成、多样性及丰度对（较环境温度升高4℃的）土壤增温具有耐受性，未出现显著改变。与之相对的是，微生物活性与碳利用效率则随土壤增温显著提升。