Assessing the effectiveness of biodegradable mulching film in vineyard: a case study in Southern Italy

In recent decades, intensive agronomic practices, combined with the growing impacts of climate change, have created a harmful synergy for the environment, leading to significant soil degradation and a subsequent decline in the quality of agri-food products. The wine sector is no exception and is particularly affected due to the need to balance grape quality, adapt vine cultivars, and secure the future incomes of farmers.

A key element in future climate simulations is a significant and widespread decrease in rainfall during the grapevine growing cycle at Italian latitudes.

In this context, with the support of Next Generation EU funds, efforts are being made to promote the transition from a linear economic model—characterized by the traditional cycle of extraction, production, consumption, and disposal—to a circular economy model centred on the three Rs: Reuse, Reduce, and Recycle. This concept can be completely applied in the agricultural sector by maximizing the use of resources. Waste products from transformation processes can be reintroduced into the agricultural system in various forms.

The aim of this work based on the use of biodegradable mulching film in viticulture, embraces these aspects by proposing an agronomic solution with the following benefits: i) preserve the soil water content during the vine cultivation by applying a biodegradable mulching film obtained from the waste of the winemaking process; ii) reduce at the same time the soil pollution caused by plastic materials.

To obtain the biofilm, grape pomace (GP) was dried and milled using a grinding machine. Cellulose Acetate (CA) and GP composites were prepared by using a melt mixing method. GP was first added to CA in amounts such that the final concentrations of GP were 10% and 30% wt. The obtained biofilms were then cut and used as mulching films in pots with grape plants in experimental trials. A comparison of pots with biofilm at different concentrations of GP was made with the control (no biofilm) and also with conventional PVC film. The monitoring concerned young grapevine plants of the Aglianico cultivar. The experimental trial was conducted during the season 2024. The plants were cultivated in 25x25 cm pots under outdoor environmental conditions filled with soil sampled up to a depth of 20 cm from a local wine farm.

The soil water content and temperature were monitored through the use of sensors connected to a datalogger for saving data with hourly time step timing, and biometric parameters were measured during the the growth cycle; finally, the LAI index was estimated for each of the theses examined. The weather data were also collected by means of meteorological station near the experimental field. The results in terms of temperatures and water content in pots, showed differences between the different biofilm treatments: the 10% had a very similar behaviour compared to the classic PVC mulch film, while the 30% biofilm treatment had slightly lower performances compared to the 10% and PVC treatments. This is a very promising result for water conservation, beneficial for the optimal growth of vines.