Vegetation control on long-term to short-term landscape evolution from thermochronology and remote sensing

热年代学和遥感对长期到短期景观演变的植被控制

• 批准号: 408246671
• 负责人: Professor Dr. Jörg Bendix
• 金额: --
• 依托单位: Arbeitsgruppe Geologie und Geodynamik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/408246671?language=en
• 关键词: Vegetation; control; long; term; short

This proposal outlines a project that follows the aims of the SPP "EarthShape" by investigating the role of biota for Earth’s shaping processes. This study aims to (i) test the primary assumption of EarthShape that all primary areas share a similar long-term tectonic (rock uplift) history, and (ii) reveal the impact of biota and geomorphologic expression on erosion and sediment transport over millennial timescales along a distinct climate and ecological gradient in the Chilean coastal range. A current assumption of EarthShape is that all four primary areas share the same tectonic (rock uplift) history, and consequently observed lateral variations in topography and surface processes are solely triggered by climate and biota. Tectonic studies and pilot thermochronological data presented in this proposal suggest that this may not be true – which means that there could be a latitudinal gradient in tectonic forcing, thereby biasing any conclusions about biota-topography-erosion relations. We will apply bedrock low-temperature thermochronology (apatite (UTh)/ He and fission track method) and thermal-kinematic modelling (PECUBE) to reconstruct the Myr-scale tectonic (rock uplift) history of all four primary areas investigated in EarthShape. Results are highly relevant for observational as well as modelling studies investigating large-scale tectonic-climate-biota interactions and landscape evolution (cf. phase II EarthShape proposals: PIs Ehlers and Hickler, Schaller and van der Kruk, Mutz and Niedermeyer). Detrital (tracer) thermochronology will be applied to all primary areas of EarthShape to identify the driving forces of millennial Earth surface processes, such as the links between vegetation cover, geomorphic expression, erosion and sediment transport. This is done by statistically relating the detrital age distributions measured in river sand to the source areas in analysed catchments. Geomorphic and biota metrics will be derived from various remote sensing data. Geomorphic erosion factors will be calculated from digital elevation models (ASTER, LiDAR), whereas vegetation erosion factors will be derived from analysing multispectral satellite data (Sentinel, Landsat) combined with field work. Resulting relative erosion maps will be combined with cosmogenic-nuclide erosion rates (e.g. EarthShape phase I+II, PIs Schereler et al., Schaller and van der Kruk) to derive high-resolution millennial erosion rate maps for all primary areas of EarthShape. We expect that this innovative multi-disciplinary approach (combining thermochronology and remote sensing data) will advance our understanding of tectonic-climate-biota landscape dynamics.

该提案概述了一个遵循最高人民检察院“地球形状”目标的项目，即调查生物区系在地球形成过程中的作用。本研究的目的是（一）测试地球形状的主要假设，即所有主要地区都有一个类似的长期构造（岩石隆起）的历史，（二）揭示生物群和地貌表达的侵蚀和沉积物输送的影响超过千年的时间尺度沿着在智利沿海地区的一个独特的气候和生态梯度。目前对地球形态的假设是，所有四个主要区域都有相同的构造（岩石隆起）历史，因此观察到的地形和表面过程的横向变化完全是由气候和生物群触发的。本提案中提出的构造研究和试点热年代学数据表明，这可能不是真的-这意味着可能有一个纬度梯度的构造作用力，从而偏见的生物群-地形-侵蚀关系的任何结论。我们将应用基岩低温热年代学（磷灰石（UTh）/ He和裂变径迹方法）和热运动学建模（PECUBE）来重建EarthShape中调查的所有四个主要区域的Myr规模构造（岩石隆起）历史。这些结果与观测和建模研究高度相关，这些研究调查了大规模的构造-气候-生物群相互作用和景观演化（参见第二阶段的地球形状建议：PI Ehlers和Hickler，Switcher和货车der Kruk，Mutz和Niedermeyer）。碎屑（示踪）热年代学将应用于EarthShape的所有主要领域，以确定千年地球表面过程的驱动力，如植被覆盖、地貌表现、侵蚀和沉积物迁移之间的联系。这是通过统计相关的碎屑年龄分布测量河砂的源区分析集水区。将从各种遥感数据中得出地貌和生物区系指标。地貌侵蚀因素将从数字高程模型（ASTER、LiDAR）计算，而植被侵蚀因素将从分析多谱段卫星数据（Sentinel、Landsat）并结合实地工作得出。由此产生的相对侵蚀图将与宇宙成因核素侵蚀率相结合（例如，EarthShape阶段I+II，PI Schereler等人，Szier和货车der Kruk），以获得地球形状的所有主要领域的高分辨率千年侵蚀率地图。我们期望这种创新的多学科方法（结合热年代学和遥感数据）将促进我们对构造-气候-生物景观动态的理解。