LTREB: Long-term Detrital Controls on Soil Organic Matter Stabilization

土壤有机质（SOM）所含的碳比植物生物量和大气的总和还要多。尽管其在全球生命支持系统中发挥着重要作用，但调控SOM积累、稳定和周转的生物、化学和物理过程之间的相互作用尚不清楚。1997年在H.J.安德鲁斯森林开始的DIRT（碎屑输入和清除处理）实验是一项长达数十年的实验，该实验将植物凋落物输入西部针叶林的大片土地。这个实验旨在解决这样的问题：是什么控制了森林土壤中碳的长期储存？SOM的哪些化学和物理组分最稳定？添加碎屑能增加土壤碳储量吗？还是最大储量完全由气候和土壤矿物学决定？通过跟踪未来几十年土壤碳的变化，我们将直接解决这些长期问题。DIRT实验具有数十年的实验性质，非常适合探索植物碎屑质量和数量在决定SOM积累中的作用，这是当前生态系统模型中一个重要的未知因素。此外，本研究侧重于本科生荣誉学生的研究训练，本实验将被纳入俄勒冈州立大学所有荣誉环境科学学生必修的荣誉生态学课程。该实验的数据和土壤将通过安德鲁斯LTER网站提供给全球的研究人员。在未来的几十年里，研究人员、学生和气候建模者都可以使用这个实验。

Soil organic matter (SOM) contains more carbon than plant biomass and the atmosphere combined. Despite its important role in the global life support system, interactions among biological, chemical, and physical processes regulating SOM accumulation, stabilization, and turnover are poorly understood. The DIRT (Detrital Inputs and Removal Treatments) experiment, started at the H.J. Andrews Forest in 1997, is a multi-decade experiment that manipulates plant-litter inputs to large plots in a western coniferous forest. This experiment is designed to address such questions as: what controls the long-term storage of carbon in forest soils? What chemical and physical fractions of SOM are most stable? Can added inputs of detritus increase soil carbon storage, or is maximum storage determined exclusively by climate and soil mineralogy? By following changes in soil carbon in the DIRT plots over the next few decades, we will address these long-term questions directly.The multi-decade, experimental nature of the DIRT experiment is uniquely suited to explore the role of plant detrital quality and quantity in determining SOM accumulation, which is a significant unknown factor in current ecosystem models. In addition, this research focuses on research training of undergraduate Honors students, and this experiment will be incorporated into an Honors Ecology course required of all Honors Environmental Science students at Oregon State University. Both data and soils from this experiment will be made available to researchers across the globe through the Andrews LTER web site. This experiment will be available to researchers, students and climate modelers for decades to come.