dataset_Chomeletal2022_natcom.xlsx

We quantify how grassland management modifies the transfer of recent photosynthates and soil nitrogen through plants and soil food webs during a post-drought period in a controlled field experiment, using <em>in situ</em> 13C and 15N pulse-labelling in intensively and extensively managed fields. For this we simulated summer drought using rainfall shelters on paired extensively and intensively managed mesotrophic grasslands across three geographically distinct locations in northern England with similar soils, vegetation and topographical conditions. In both control and drought plots, plant communities and soil food web (microorganisms and mesofauna) biomass and composition were determined. To simultaneously investigate the short-term allocation of N and recently assimilated C below-ground during a post-drought period, we pulse-labelled plants with 13C-CO2, and soil with 15N-NO3 at the end of the simulated drought. We traced the incorporation of 13C and 15N into plant shoot and roots, microbial biomarkers, soil mesofauna trophic groups and soil CO2 and N2O fluxes over a 20-day post-drought period.

本研究依托一项受控野外实验，通过在集约化管理与粗放管理样地中开展原位（in situ）13C与15N脉冲标记（pulse-labelling），量化了干旱后时期草地管理对植物与土壤食物网（soil food web）转运近期光合产物及土壤氮素过程的调控效应。为此，我们在英格兰北部3个土壤、植被与地形条件均相似的地理独立样点，针对配对设置的集约化与粗放管理中营养型草地（mesotrophic grasslands），利用防雨棚模拟夏季干旱。在对照组样地与干旱处理组样地中，我们均测定了植物群落、土壤食物网（包含微生物与中型土壤动物（mesofauna））的生物量与群落组成。为同步探究干旱后时期氮素与新近同化碳的地下短期分配过程，我们于模拟干旱结束时，分别以13C-CO2对植物进行脉冲标记、以15N-NO3对土壤进行脉冲标记。我们在为期20天的干旱后监测周期内，追踪了13C与15N在植物地上部分与根系、微生物生物标记物（microbial biomarkers）、土壤中型土壤动物营养类群以及土壤CO2与N2O通量中的整合与分布过程。