Drivers of soil respiration in response to nitrogen addition in a Mediterranean mountain forests

We investigated the effects of soil N enrichment on soil respiration in the ecotone between Scots pine and Pyrenean oak forests (Mediterranean mountain, Central Spain) and whether these effects were mediated by changes on selected soil chemical and biological properties. Two N deposition rates were simulated –10 (medium) and 40 kg N ha^-1 a^-1 (high)– over the background deposition (control), in two neighbouring forests in which tree species (oak or pine) shapes soil stoichiometry and microbial communities. Manipulation of N deposition rates was carried out at three-month intervals throughout three years. Soil respiration was monitored during 2014-2017 time period, and soil samples were collected annually.<br>Results published in Fernández-Alonso et al., 2021 - Biogeochemistry. https://doi.org/10.1007/s10533-021-00827-2

本研究以西班牙中部地中海山地的苏格兰松（Scots pine）与比利牛斯栎（Pyrenean oak）林生态交错带为研究对象，探究土壤氮富集对土壤呼吸（soil respiration）的影响，以及该效应是否通过选定的土壤化学与生物学属性变化介导。
本研究以背景氮沉降为对照组，模拟设置了两种氮沉降梯度：10 kg N·ha⁻¹·a⁻¹（中氮）与40 kg N·ha⁻¹·a⁻¹（高氮）；实验设置于两片相邻森林中，二者的优势树种分别为栎树与松树，其树种特征可塑造土壤化学计量比（soil stoichiometry）与微生物群落（microbial communities）结构。
本研究以三个月为间隔开展氮沉降操控实验，实验持续时长共计三年。土壤呼吸监测时段为2014至2017年，土壤样品每年采集一次。
本研究结果已发表于Fernández-Alonso等（2021）发表于《Biogeochemistry（生物地球化学）》的论文，DOI：10.1007/s10533-021-00827-2