Tree identity and diversity directly affect soil moisture and temperature but not soil carbon ten years after planting

1. Soil C is the largest C pool in forest ecosystems that contributes to C sequestration and mitigates climate change. Tree diversity enhances forest productivity, so diversifying the tree species composition, notably in managed forests, could increase the quantity of organic matter being transferred to soils, and alter other soil properties relevant to the C cycle. 2. A ten-year-old tree diversity experiment was used to study the effects of tree identity and diversity (functional and taxonomic) on soils. Surface (0-10 cm) mineral soil was repeatedly measured for soil C concentration, C:N ratio, pH, moisture and temperature in twenty-four tree species mixtures and twelve corresponding monocultures (replicated in four blocks). 3. Soil pH, moisture and temperature responded to tree diversity and identity. Greater productivity in above- and below-ground tree components did not increase soil C concentration. Soil pH increased and soil moisture decreased with functional diversity, more...1. 土壤碳（Soil C）是森林生态系统中最大的碳库，可通过碳固存助力减缓气候变化。树木多样性可提升森林生产力，因此优化树种组成（尤其在人工经营林中）能够增加向土壤输入的有机质总量，并改变其他与碳循环相关的土壤理化性质。 2. 本研究依托一项为期十年的树木多样性野外试验，探究树种特异性与多样性（含功能多样性与分类学多样性）对土壤的影响。研究针对24个树种混交林与12个对应的单优纯林，对其0-10 cm表层矿质土壤的土壤碳浓度、碳氮比（C:N ratio）、pH值、含水率及温度进行了多次测定，试验设置4个重复区组。 3. 土壤pH值、含水率与温度均对树木多样性及树种特异性产生响应。树木地上与地下生物量组分的更高生产力并未提升土壤碳浓度。随着功能多样性提升，土壤pH值升高而土壤含水率降低，more...