Linking ecosystem and geomorphic processes to understand the large-scale dynamics of tropical mountains mediated by landsliding

山体滑坡是全球山区环境变化的重要因素。虽然滑坡背后的基本地质过程相对广为人知，但越来越多的证据表明，生态系统过程的生物组成部分起着重要的作用，但在很大程度上尚未得到充分研究。特别是植物的根和茎生物量——两个重要的生态系统属性——可能以复杂的方式影响山坡的稳定性。该项目调查了危地马拉东部山脉拉斯米纳斯山脉的土壤肥力、气候、生态系统属性和边坡稳定性之间的关系。之所以选择这个研究区域，是因为它受到周期性滑坡的影响，并且有相当多的研究历史。该项目首次整合了基本的生态系统概念，以更好地了解地貌和山体滑坡的演变，表明植被生物量在根和芽之间的划分至关重要。这是一个高度跨学科的项目，也将有助于妇女和未被充分代表的少数民族参与研究和推广，建立国际合作，并提供新知识的传播，这些知识将为广泛的利益相关者和学者感兴趣，包括那些对地形演变，生态系统和景观发展，碳循环和滑坡灾害地区可持续管理感兴趣的人。在之前工作的基础上，该项目利用了拉斯米纳斯山脉不同的岩性和不同的气候条件，来测试从不同岩性继承的土壤肥力的变化会影响根和芽之间生物量的分配，从而影响边坡稳定性、土壤发育，并最终导致滑坡。然而，气候条件的变化可能改变观测到的影响的大小和方向。这项工作围绕三个具体目标和相应的假设进行：1)研究影响边坡稳定性的土壤肥力和植被属性之间的关系；2)研究不同母质下滑坡土壤发育轨迹的差异；3)评估不同土壤肥力和植被动态对滑坡的相互作用。这些目标将结合地理信息系统和遥感数据、实地考察、树木年轮研究、生物地球化学和地质年代学分析以及建模来实现。

Landslides are an important agent of change in mountain settings worldwide. Although the basic geological processes underlying landslides are relatively well known, increasing evidence indicates that the living components of ecosystem processes play an important, but largely understudied, role. In particular, plant root and shoot biomass - two important ecosystem attributes - are likely to influence the stability of hill slopes in complex ways. This project investigates the relationships between soil fertility, climate, ecosystem attributes, and slope stability in the Sierra de Las Minas, a mountain range in eastern Guatemala. This study area was selected because it is subject to periodic landslides and has a considerable history of previous research. The project integrates for the first time basic ecosystem concepts to better understand the evolution of landforms and landslides, suggesting that the division of vegetation biomass between roots and shoots is critically important. This is a highly interdisciplinary project that also will contribute to the engagement of women and underrepresented minorities in research and outreach, forge international collaborations, and provide for the dissemination of new knowledge that will be of interest to a wide range of stakeholders and scholars, including those interested in landform evolution, ecosystem and landscape development, carbon cycling, and sustainable management of regions subjected to landslide hazard.Building upon previous work, this project takes advantage of the diverse lithologies and contrasting climates found in the Sierra de Las Minas, to test the overall hypothesis that variation in soil fertility inherited from different lithologies influences the partitioning of biomass between roots and shoots with consequences for slope stability, soil development, and ultimately landslide regimes. Variation in climatic conditions, however, may change the magnitude and direction of the observed effects. The work is organized around three specific goals and corresponding hypotheses: 1) examine the relationship between soil fertility and vegetation attributes that influence slope stability, 2) investigate differences in soil development trajectories in landslides underlain by different parent materials, and 3) evaluate the interactions between different soil fertilities and vegetation dynamics on landslides. These goals will be developed using a combination of geographic information systems and remotely sensed data, fieldwork, tree-ring studies, biogeochemical and geochronological analyses, and modeling.