Innovative cropping systems under extreme rainfall events - Zimbabwe

Objective

The main objective of this long-term experiment is to test the agronomic and environmental performances of innovative cropping systems under extreme rainfall events, combining field monitoring and soil-crop modelling.

Description

The experiment has been established in October 2022 on 1.4 ha at the University of Zimbabwe Farm (UZF). Three main treatments repeated three times were established: - Reduced rainfall (-30%) - Normal rainfall - Extreme rainfall events (100 mm/24h) The reduced rainfall treatments are achieved with a rainfall exclusion system, with transparent gutters covering about 30% of the surface The extreme rainfall events are obtained with an irrigation system installed at the site. Several events per season are simulated, some after top dressing applications, others at critical phenological stages (grain filling…). The date of these events varies one year from another. The idea is to create events such as leaching, runoff or waterlogging. Within these 3 rainfall treatments, 10 cropping systems are tested in a split-plot design. The experiment therefore comprises 90 plots: - Bare soil - Maize - Maize + N - Maize + Mulch - Maize + N + Mulch - Maize (100%) + cowpea (50%) intercropping - Maize (100%) + cowpea (50%) intercropping + N - Maize (50%) + cowpea (50%) intercropping - Maize (50%) + cowpea (50%) intercropping + 50% N - Cowpea The mulch is made of maize residues from the previous season applied at 6 t DM/ha. Mineral nitrogen (N) fertilizer is applied at 80 kgN/ha/yr. A weather station has been installed in November 2022, as well as soil temperature and moisture sensors at different depths (1, 5, 15 cm). Static chambers have been installed to monitor emissions of greenhouse gases. Quadrats have been installed to monitor mulch decomposition. Crop phenology is monitored on a weekly basis. Regular measurements of crop height and leaf area index (LAI) are done, as well as soil sampling for mineral nitrogen dynamics. Access tubes will be installed to monitor soil water dynamics. In October 2023, sensors to monitor the energy balance of the systems (albedo, heat fluxes) will be installed. Every year, crop biomass, crop yield and yield components at harvest at measured.

Data Access Statement

Available to collaborators only

Data license

Don't know

Data policy

Don't know

Organizations

People

Dr Rémi CARDINAEL

principal investigator

CIRAD

Agroecology and sustainable intensification of annual crops

 remi.cardinael@cirad.fr

Prof Regis Chikowo

principal investigator

University of Zimbabwe

Department of Plant Production Sciences and Technologies

 regischikowo@yahoo.co.uk