Organic matter cycling along geochemical, geomorphic, and disturbance gradients in forest and cropland of the African Tropics – project TropSOC database version 1.0
Authors: Doetterl Sebastian , Asifiwe Rodrigue K. , Baert Geert , Bamba Fernando , Bauters Marijn , Boeckx Pascal , Bukombe Benjamin , Cadisch Georg , Cooper Matthew , Cizungu Landry N. , Hoyt Alison , Kabaseke Clovis , Kalbitz Karsten , Kidinda Laurent , Maier Annina , Mainka Moritz , Mayrock Julia , Muhindo Daniel , Mujinya Basile B. , Mukotanyi Serge M. , Nabahungu Leon , Reichenbach Mario , Rewald Boris , Six Johan , Stegmann Anna , Summerauer Laura , Unseld Robin , Vanlauwe Bernard , Van Oost Kristof , Verheyen Kris , Vogel Cordula , Wilken Florian , Fiener Peter 
Published: August 2021

Abstract. The African Tropics are hotspots of modern-day land use change and are, at
the same time, of great relevance for the cycling of carbon (C) and
nutrients between plants, soils, and the atmosphere. However, the
consequences of land conversion on biogeochemical cycles are still largely
unknown as they are not studied in a landscape context that defines the
geomorphic, geochemical, and pedological framework in which biological
processes take place. Thus, the response of tropical soils to disturbance by
erosion and land conversion is one of the great uncertainties in assessing
the carrying capacity of tropical landscapes to grow food for future
generations and in predicting greenhouse gas fluxes from soils to the
atmosphere and, hence, future earth system dynamics. Here we describe version 1.0 of an open-access database created as part of
the project “Tropical soil organic carbon dynamics along erosional
disturbance gradients in relation to variability in soil geochemistry and
land use” (TropSOC). TropSOC v1.0 (Doetterl et al., 2021,
https://doi.org/10.5880/fidgeo.2021.009) contains spatially and temporally
explicit data on soil, vegetation, environmental properties, and land
management collected from 136 pristine tropical forest and cropland plots
between 2017 and 2020 as part of monitoring and sampling campaigns
in the eastern Congo Basin and the East African Rift Valley system. The
results of several laboratory experiments focusing on soil microbial
activity, C cycling, and C stabilization in soils complement the dataset to
deliver one of the first landscape-scale datasets to study the linkages and
feedbacks between geology, geomorphology, and pedogenesis as controls on
biogeochemical cycles in a variety of natural and managed systems in the
African Tropics. The hierarchical and interdisciplinary structure of the TropSOC database
allows linking of a wide range of parameters and observations on soil and
vegetation dynamics along with other supporting information that may also be
measured at one or more levels of the hierarchy. TropSOC's data mark a
significant contribution to improve our understanding of the fate of
biogeochemical cycles in dynamic and diverse tropical African
(agro-)ecosystems. TropSOC v1.0 can be accessed through the Supplement
provided as part of this paper or as a separate download via
the websites of the Congo Biogeochemistry Observatory and GFZ Data Services
where version updates to the database will be provided as the project
develops.