Belowground Dynamics in a California Blue Oak Woodland: Production, Mortality and Decomposition of Oak and Grass Roots

9509879加州蓝橡树林地的地下动态：橡树和草根的生产、死亡和分解为植物获取养分和水分，并提供结构支持。根也会生长、死亡和分解，使它们成为生态系统碳和养分循环的一部分。虽然根具有非常重要的生态系统功能，但它们位于地下的位置使得研究它们变得困难。因此，与植物的其他部分相比，关于根的数据更少。本研究项目关注根系动态，并提出以下问题：(1)细根的生长、死亡和分解在空间和季节上是如何变化的？(2)橡树和牧草是以有限的竞争共存，还是为了水分和养分而竞争，特别是在每年的夏季干旱期间？这些问题将通过测量季节性土壤水分和温度、土壤呼吸和根系动态来回答。橡树菌根是某些真菌和植物根之间的有益伙伴关系，将被研究。由于蓝橡树和一年生草本植物有不同类型的菌根，这项研究还将检查菌根类型是否会影响植物吸收水分和养分的程度。这项研究将有助于进一步维护加州的蓝橡树林地，并了解菌根如何改变植物的竞争。

9509879 BLEDSOE Belowground Dynamics in a California Blue Oak Woodland: Production, Mortality and Decomposition of Oak and Grass Roots Roots acquire nutrients and water for plants, as well as providing structural support. Roots also grow, die, and decompose, making them part of ecosystem carbon and nutrient cycles. Although roots have very important ecosystem functions, their belowground location makes them difficult to study. Consequently, less data exist for roots than other parts of plants. This research project focuses on root dynamics and asks these questions: (1) How does fine roots growth, death, and decomposition vary spatially and seasonally? (2) Do oaks and grasses coexist with limited competition or do they compete for water and nutrients, especially during annual summer drought? These questions will be answered by measuring seasonal soil water and temperature, soil respiration, and root dynamics. Oak mycorrhizae, a beneficial partnership between certain fungi and plant roots, will be studied. Because blue oaks and annual grasses have different types of mycorrhizae, the research also will examine whether mycorrhizal types affect how well the plants take up water and nutrients. This research will help further maintenance of California's blue oak woodlands and understanding how mycorrhizae alter plant competition.