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Plasticulture is a technique widely affirmed throughout Europe and the rest of the world that employs plastic material for protecting agricultural cultivations, e.g., soil mulching, low/middle tunnel covering, and greenhouse farming. Because of their effects on the sustainability of agricultural production, these materials present serious environmental drawbacks. Even if plastic recycling is a consolidated technical solution, several obstacles hinder the mechanical recycling of film used in plasticulture. Mostly, the degradation of its mechanical characteristics, due to aging and simultaneous contamination with agrochemicals used for fighting plant disease and ensuring crop health, plays a major hampering role. In the present paper, the results of laboratory tests on agricultural PE-LD plastic film for greenhouse covering, artificially aged for different lengths of time and treated with two different agrochemicals (fungicide and anti-aphid), are presented. The contamination with agrochemicals resulted in a considerable reduction in mechanical properties throughout the usage phase even if in samples that underwent twofold spraying, slower degradative kinetics were observed. In conclusion, based also on the measured changes in the Carbonyl Index value, it is doubtful that this plastic film would be included in a mechanical recycling process.

Plastic films used for crop protection have reached notable consumption all over Europe, as well as in the rest of the world. This phenomenon however poses a serious environmental problem connected with the impact on the sustainability of agricultural production and relevant plastic footprint. Mechanical recycling of agricultural plastics is a common technique, but limited by many factors, as the loss of mechanical properties of plastic film. This phenomenon, due to its ageing after being exposed to natural weather conditions, plays a crucial role, especially when aggravated by contamination with agrochemicals ordinarily used for crop health and pest management. This article reports the result of some laboratory tests on agricultural plastic film, artificially aged for different periods and contaminated with two different agrochemicals (anti-aphid or fungicide). These results show that the impact of agrochemicals on plastic film is considerable, since it worsens the ageing process of the plastic film, conducting a more rapid reduction in its mechanical properties—mostly, a faster reduction in the elongation at break below 50% of the corresponding value of the virgin plastic film. This phenomenon, other than reducing the working life of the plastic film, gives it a low potential for being transformed into a closed-loop recycled material when entering the recycling stage. The increase in the value of the detected Carbonyl Index (CI) confirms the tendency of the material to degrade rapidly when in contact with agrochemicals, hence indicating that it may be impossible to mechanically recycle it.

Plastic pollution, largely perceived by the public as a major risk factor that strongly impacts sea life and preservation, has an even higher negative impact on terrestrial ecosystems. Indeed, quantitative data about plastic contamination on agricultural soils are progressively emerging in alarming ways. One of the main contributors to this pollution involves the mismanagement of agricultural plastic waste (APW), i.e., the residues from plastic material used to improve the productivity of agricultural crops, such as greenhouse covers, mulching films, irrigation pipes, etc. Wrong management of agricultural plastics during and after their working lives may pollute the agricultural soil and aquifers by releasing macro-, micro-, and nanoplastics, which could also enter into the human food chain. In this study, we aimed to develop a methodology for the spatial quantification of agricultural plastics to achieve sustainable post-consumer management. Through an inductive approach, based on statistical data from the agricultural census of the administrative areas of the Italian provinces, an agricultural plastic coefficient (APC) was proposed, implemented, and spatialized in a GIS environment, to produce a database of APW for each type of crop. The proposed methodology can be exported to other countries. It represents valuable support that could realize, in integration with other tools, an atlas of agricultural plastics, which may be a starting point to plan strategies and actions targeted to the reduction of the plastic footprint of agriculture.

In arid climates, the optical properties of plastic-covered greenhouses deteriorate very quickly. To examine the effect of greenhouse shape and orientation on the degradation rate of cover optical properties, four greenhouse prototypes were constructed in two shapes (duo-pitched roof and tunnel), covered with a 200 µm thick low-density polyethylene film. Two types were oriented in the North–South direction, the other two in the East–West direction, and all were exposed for one year to an arid climate. Samples were taken from the different surfaces of each cover for testing. The total transmittance (Ts) and reflectance (Rs) of the samples were measured and averaged to obtain the whole cover properties (T and R). Measurements were carried out periodically every 30 days for the four prototypes. The degradation behavior of the optical properties of each cover surface (Ts, Rs) and the whole cover (T, R) was investigated for the four film covers during the exposure time. Results show that the degradation rate of Ts depends on the surface location and the cover orientation. Among the different surfaces of the four prototype covers, the maximum difference in the Ts value between the E and N surfaces for the tunnel cover oriented in the N–S direction was 15.5%. Although the variation of the Ts value among the different cover surfaces was found, the time dependences of the whole cover transmittance (T) for the four covers tested were almost similar. Accordingly, the shape and orientation of the small size greenhouses did not significantly affect the degradation rate of the cover optical properties. In the four covers tested, the reduction in the global solar radiation transmittance (T) was 27–31% after one-year exposure compared to the new film. Nonlinear correlation was developed to predict the degradation rate of the cover transmittance as a function of the accumulated solar irradiance.

In recent decades, the construction industry has advanced in its use of natural green resources, such as vegetable fibers (e.g., flax, hemp, jute, etc.) added in concrete mixtures, to create building materials that are both economically and environmentally sustainable. The pricing, low energy cost, and environmental sustainability of these natural fibers are driving this interest. The quantity of fibers and the ratio of fiber length to its transverse diameter (aspect ratio) are critical characteristics that have a decisive impact on concrete’s mechanical qualities. The influence of the aspect ratio of Arundo donax fibers on the tensile characteristics of concrete blocks was specifically investigated in this study. These fibers were collected from the outer section of the stem of this plant, which grows commonly in Mediterranean locations, but that is also found all over the world. Experiments were carried out on cylindrical concrete blocks with a constant amount of fiber (1 percent by weight) and different aspect ratios: 30, 50, and 70 (mm/mm) respectively, to assess their tensile strength, even when compared with concrete blocks without any fiber addition. Tensile tests on Arundo donax fibers were also conducted, with the aim to contribute to the analysis of their interaction with cementitious matrices, and to assess differences between the various compositions. The results showed a direct impact of the aspect ratio on the final tensile strength of concrete blocks, with higher aspect ratios producing superior tensile properties.

The agricultural sector has benefitted over the last century from several factors that have led to an exponential increase in its productive efficiency. The increasing use of new materials, such as plastics, has been one of the most important factors, as they have allowed for increased production in a simpler and more economical way. Various polymer types are used in different phases of the agricultural production cycle, but when their use is incorrectly managed, it can lead to different environmental impacts. In this study, an applied and simplified methodology to manage agricultural plastics monitoring and planning is proposed. The techniques used are based on quantification through the use of different datasets (orthophotos and satellite images) of the areas covered by plastics used for crop protection. The study area chosen is a part of the Ionian Coast of Southern Italy, which includes the most important municipalities of the Basilicata Region for fruit and vegetable production. The use of geographical techniques and observation methodologies, developed in an open-source GIS environment, enabled accurate location of about 2000 hectares of agricultural land covered by plastics, as well as identification of the areas most susceptible to the accumulation of plastic waste. The techniques and the model implemented, due to its simplicity of use and reliability, can be applied by different local authorities in order to realize an Atlas of agricultural plastics, which would be applied for continuous monitoring, thereby enabling the upscaling of future social and ecological impact assessments, identification of new policy impacts, market searches, etc.