|Phase II (2019-'21)|
II P1: FIRE Induced Element Cycling
II P6: Bio-Geomorphology
II P7: Biota, fracture, thresholds
II P11: DeepES - Weathering Geochemistry
II P13: DeepES - Geophysical Imaging
II P14: DeepES - Microbial activity
II P15: DeepES - Geomicrobiology
II A2: Bioweath
|Phase I (2016-'18)|
I P2: Coupled Modelling
I P3: Biofilms & Weathering
I P5: Crustweathering
I P6: Root Carbon
I P7: Paleoclimate
I P9: Sediment Transport
I P10: Phosphorus solubilization
I P11: Green & Grey world
I P12: Biogenic Weathering
I A3: Carbon & Nutrient Fluxes
Investigator Names and Contact Info:
Chilean Collaborators Involved:
PhD 5a: mSecco
supervisor: H. Wittmann-Oelze, co-supervisors: D. Sachse, P. Frings, A. Bernhardt
PhD 5b: pSecco
supervisor: A. Bernhardt, co-supervisors: D. Sachse, P. Frings, H. Wittmann-Oelze
supervisor: A. Bernhardt, Co-supervisor: H. Wittmann-Oelze
Understanding landscape response to climate change is a central problem in the geosciences today, as substantial future changes in precipitation patterns and intensity are expected. Here we aim to investigate these responses by taking advantage of the unique vegetation and hydrological gradient along the Chilean continental margin and the climatic change over the last 20.000 years recorded in marine sedimentary archives off-shore.
Specifically, this project seeks to identify the cascade of changes in weathering, erosion, and sediment export following the large hydrologic and vegetation changes along the Chilean coast from the Last Glacial Maximum (LGM) to present. We will use state-of-the-art tools, e.g. compound distribution, and compound-specific carbon and hydrogen isotope composition of leaf wax n-alkanes as indicators for vegetation type and hydrology, Lithium stable isotopes to constrain weathering intensity, and meteoric cosmogenic 10Beryllium (10Be) to stable 9Be (10Be/9Be) ratios to quantify weathering and erosion rates. In detail, this project will:
a) Identify how present-day climate, vegetation, weathering, and erosion vary along the Chilean margin and how they are recorded in inorganic and organic geochemical proxies. This aim requires establishing how modern gradients in hydrology, vegetation, weathering, and erosion are recorded in the proxies and thus the analysis of suspended sediment material from modern rivers draining the Chilean ranges and the analysis of marine surface sediment. This will lead to a calibration of the proxies, as well as an assessment of their fidelity in marine surface sediments by a comparison of the core tops with the modern river data.
b) Reconstruct the temporal development of climate, vegetation, weathering, erosion, and sediment export since the LGM along the Chilean margin. To achieve this aim, we will analyze three marine sediment cores covering the time period from the LGM (ca. 20.000 years ago) to today with inorganic and organic proxies.
3) Identify the temporal leads and lags between climate, vegetation, weathering, erosion and sediment export, and analyze and mechanistically understand spatio- temporal patterns and their differences in the studied regions (i.e. arid, semi-arid, humid). We will compare lead and lag-time patterns between the key proxies along three study sites of the Chilean climate gradient to understand drivers of these lags and the feedbacks between climate, vegetation, weathering, erosion, and sediment export to the ocean.
This proposal is a first-time proposal and newly established within EarthShape phase 2.