hide
Free keywords:
-
Abstract:
Croplands are vital ecosystems for human well-being and provide important ecosystem services such
as crop yields, retention of nitrogen and carbon storage. On large (regional to global)-scale levels, assessment
of how these different services will vary in space and time, especially in response to cropland management, are
scarce. We explore cropland management alternatives and the effect these can have on future C and N pools
and fluxes using the land-use-enabled dynamic vegetation model LPJ-GUESS (Lund–Potsdam–Jena General
Ecosystem Simulator). Simulated crop production, cropland carbon storage, carbon sequestration and nitrogen
leaching from croplands are evaluated and discussed. Compared to the version of LPJ-GUESS that does not
include land-use dynamics, estimates of soil carbon stocks and nitrogen leaching from terrestrial to aquatic
ecosystems were improved.
Our model experiments allow us to investigate trade-offs between these ecosystem services that can be provided
from agricultural fields. These trade-offs are evaluated for current land use and climate and further explored
for future conditions within the two future climate change scenarios, RCP (Representative Concentration Pathway)
2.6 and 8.5. Our results show that the potential for carbon sequestration due to typical cropland management
practices such as no-till management and cover crops proposed in previous studies is not realised, globally or
over larger climatic regions. Our results highlight important considerations to be made when modelling C–N interactions
in agricultural ecosystems under future environmental change and the effects these have on terrestrial
biogeochemical cycles.
