Within the framework of the PAPILLONS project, researchers at IMDEA Water (Madrid, Spain) have set up a runoff and infiltration experiment to investigate the fate of microplastics (MPs) in agricultural soils.
The experiment aims to analyse the transport of agricultural MPs through runoff, sub-surface runoff and within the soil, towards groundwater. Additionally, the assay will explore the effect of crops on MP mobility and the potential release of chemical additives into the water.
The experiment
In mid-February, six stainless steel modified Pinson collectors with an area of 2 m2 were installed at IMDEA Water imposing a slope of 5°. All of them were filled with soil and the uppermost 4 cm were mixed with MPs from biodegradable mulching films provided by NIVA. Barley (Fandaga variety) was planted only in three Pinson collectors whereas the rest of collectors were left with bare soil. An irrigation system was specifically designed to ensure the best growing conditions.
The experiment will last for approximately 5 months, until the barley harvest. Throughout the experimental run, samples of run-off water from rainfall and irrigation, infiltration water – collected through by drainage pipes at different depths – and interstitial water from soil will be periodically collected. After the barley harvest, soil samples from cultivated and bare soil collectors will be taken for detecting MP contents at different depths. Samples for MP and chemical additive determinations will be analized at SYKE and UCT, respectively. Obtained results will provide insights into MP and associated additives transport in a simulated agricultural scenario.
This research activity is part of the Task 2.3. MNP and additives transport to groundwater, surface water, air and uptake by biota and crop (part of the Cross-Cutting Theme 3) of the PAPILLONS research project.
Image 1. Six stainless steel modified Pinson collectors installed at IMDEA Water.
Image 2. Barley leaves 15 days after planting.
Image 3. Modified Pinson collector with taps to collect runoff and infiltration water (at 10 and 30 cm depths).
Image 4. Spreading of the barley seeds over the soil.
(Photos taken by Cynthia Rieckhof Rivas, 2023)