Final Report Summary - AGROBIOFILM (Development of enhanced biodegradable films for agricultural activities)
Executive Summary:
The consortium behind this project – a group of European SME suppliers and users of agricultural plastics – wishes to address a major market opportunity through the development and performance demonstration of mulch films able to fulfil the three main following requirements: to be environmentally friendly (i.e; biodegradable in soil without containing a high content in fossil carbon); to be compliant with common farming methods; and to match or improve crops performance as expected in the case of conventional plastic films. Specifically, the consortium wants to enhance mulch films based on biodegradable raw materials, which will be customized to specific crops and regions, with a possible positive effect on crop yield and quality, pests and/or disease control, soil preparation and fertilization. Special attention is dedicated to the integration of all the knowledge acquired through a full life-cycle analysis and a performance/cost-efficiency validation. The goal of this project is to use a very recent Mater-Bi® formulation characterised by a higher content in renewable feedstocks as compared to the other biodegradable mulch films currently used, the Novamont’s Mater-Bi® CF04P grade, in order to customize enhanced biodegradable mulch films (BMF) that should be more competitive at both the technical and the economic point-of-view by optimising the processing conditions. The CF04P raw-material is chemically aliphatic/aromatic co-polyester with a starch matrix. Although the use of starch-based polymers is widely reported in literature, and object of thorough research, the novelty of this new polymer formulation brings new questions needing to be answered through extensive research on its application to agriculture purposes. This grade will thus be compared with other biodegradable polymers that are already in use for agricultural purposes, and particularly with the Novamont’s Mater-Bi® NF grade. The NF and the CF grades share the same matrix (starch), but the NF grade is composed at more than 50% of synthetic polyesters (biodegradable but from fossil carbon origin) while CF offers a much more sustainable since it is composed of renewable raw-materials from vegetable oils) and economic solution. The agronomic performance of these biodegradable mulch films was assessed through field experiments conducted on four selected crops known to need specific requirements in terms of film properties and life time: peppers, melons, strawberries and vines.
The objective of this study is to provide effective solutions to convertors that can be used to standardize mulch film production with highly sustainable raw materials throughout Europe. These standardization needs to be done across multidisciplinary areas, such as polymer science, polymer extrusion (blown film), agronomical science, regulatory affairs for new biodegradation standards, as well as throughout European fields in order to fully understand this new polymer, from renewable raw materials origins, and adapt its production either to different crop or to the wide European fields characteristics.
AGROBIOFILM project will significantly promote the uptake of highly productive and environmentally friendly farming practices among end-users, who are currently facing a number of competitive challenges threatening the economic stability of the sector. The project will also increase the competitiveness of the participating SME manufacturers by providing them with a state-of-the-art platform to develop competitive biodegradable mulch films, and therefore widening the applicability of their biodegradable products to new markets.
The concept of biodegradable mulch films is itself not new. There are several suppliers claiming the biodegradability of their films, often misleading end-users, because their final products are not complying with the adequate standards or fail to achieve its objectives.
The novelty of AGROBIOFILM exists in the product-oriented methodology with a bottom-up approach (from farmer to mulch film producer) towards end-users needs.
Due to the perceived prohibitive price and the increasing performance indicators of existing products, the reality is that major consumers of mulch films in Europe are still using PE films and thus, generate an enormous quantity of plastic waste, despite possible alternative solutions. By covering film customization, from crop selection to the formulation step until the final performance indicators, where state-of-the-art results on high-tech mulch films will be integrated, the consortium aims to overcome all technical and scientific barriers for end-user adoption. Moreover, the exhaustive analysis plan enable the widening of mulch film application, as is the case of the tests in vineyards, where the films are not currently used. AGROBIOFILM is a vertical integrated project, involving stakeholders across the project. In fact, this project goes beyond polymer science and lab standards for biodegradability merging it with agronomic sciences to an extent and with a methodology, which to our knowledge has never been applied. Our project goes from extrusion industry to biodegradation on soil analysis, complemented with a complete Life Cycle Assessment, with a deep involvement of end-users in the project implementation, allowing using the specific management practices of real farmers.
Project Context and Objectives:
The overall objective of AGROBIOFILM is to develop biodegradable mulch films with performances demonstrated and validated scientifically during the effective duration of the project – 30 months - with the objective to extend their application at both a broader scale and a wider range of end-users (horticulture, vineyards and other perennial crops). The properties of this innovative starch-based mulch is improved as compared to these of already existing mulch films (made either of polyethylene or of biodegradable polymers such as older Mater-Bi formulations):
1-As compared to PE mulch films, its better adapted to the farmer’s needs since customised according to a targeted crop with the objective to match mulch life cycle with horticultural crops life cycle;
2-As compared to biodegradable mulch films already existing, are more efficient to modulate light transmission and reflectance due to colours additives that will be added to the CF04P raw material; besides black, the planned mulch colours to be tested are transparent, white/black, silver/white/black and green;
3-As compared to biodegradable mulch films already existing, present lower values of water vapour permeability, as consequence of additive incorporation in the industrial processing.
4-As compared to PE and other biodegradable mulch films, are more eco-friendly owing to their lower content in fossil carbon with a biodegradable behaviour compatible with different soil quality (horticulture/vineyard) and type of exposition as related to the farming practice used (burying in soil after harvest or let at the soil surface);
5-As compared to other biodegradable mulch films, Agrobiofilm mulch are targeted for a more economically and energetically competitiveness due to an initial lower price of the raw material, a reduced film thickness, and also the incorporation of scraps and optimised specific processing conditions;
6-At the agronomic point of view, proved to be at least as efficient as the already existing mulch films based on PE and other biodegradable polymers (weed control, water saving, pest & diseases control, yield, quality, earliness of harvest).
Main objective of AGROBIOFILM project is to overcome the scientific and technical barriers that currently prevent biodegradable plastics from becoming a viable substitute for PE films. Additionally, the new CF04P based BMFs must reach, at least, same results reported in literature for NF grade based BMFs.
At the beginning of the project, the main barriers were identified as:
1. The manufacture of the BMFs: the processing parameters need to be optimized to ensure the production of good quality films. Indeed, the quality of the films may significantly vary depending on the additives introduced in the formulations to match the specific needs of the targeted crops (in terms of life span, water permeability, biodegradability pattern, etc.;
2. The application of the BMFs in the field: setting the films in the field uses the same equipment as traditional plastic but requires different operating procedures. The degree of contact between the mulch film and the soil (thermal contact resistance) greatly affects its performance and stretching strength must be adapted according to the films thickness, otherwise risking the rip/stretch of the film, which would no longer be efficient since earlier degradation could occur;
3.The short life time of the existing biodegradable films. Indeed, “Commercial Mater-Bi® films are available for crops with a cycle between 2 and 6 months” (Guerrini, personal communication, 2011). In fact, biodegradable mulch films (BMF) haven’t yet been widely tested or applied to crops with long cycles (such as vines) on a systematic and scientific basis;
4.The higher water vapour permeability of BMFs in comparison with PE films, leading to either a higher water infiltration in soil from rain and dew or higher water evaporation from the soil, especially during hot seasons;
5.The potential existence of sides effects of the biodegradable films on the crops: creation of favourable conditions for the development of diseases and pests affecting the crops, dirty marks on the harvested fruits or vegetables due to the adhesion of film pieces, etc.;
5.The biodegradation of the mulch films: whatever the crop, the climate and the soil type, a total biodegradation has to be guaranteed in a suitable period of time (to be determined for a given crop);
6.The environmental liability of the products : it has to be proved through a long term analysis of the products life cycle.
Since the beginning it was clear that overcome these barries implies a detailed study on:
1. Biodegradable mulch film optimization tailor made for usage in specific targeted regions and crops with respect to crop yield (in terms of quality and quantity);
2. The ability to reduce or fully eliminate the use of herbicides, especially on crops where bare soil is the common practice (e.g. vineyards);
3. The possibility to reduce water consumption
4. Its effect on pests and diseases control.
Project Results:
Agrobiofilm project was dedicated to 2 major type of agricultural crops: Horticultural crops (normally annual crops) and Perennial crops (eg, Vines).
Results from Horticulture trials:
Along AGROBIOFILM project development, in Portugal and Spain, a total of 36 Agrobiofilm modalities with different colours, thicknesses and formulations were tested and compared with 4 PE modalities, 5 NF grade modalities and bare soil modality - in real field conditions (short and long cycle crops), pilot and laboratorial scale – with the goal of finding the most suitable solution for each crop performance.
The air temperature, relative humidity, rainfall and solar radiation were typical, when comparing to the data from the last decade. According to this, the performance of Agrobiofilms can be applied to regions where the edapho-climatic conditions are similar.
The mechanical properties of the different Agrobiofilms were assessed visually and were considered adequate to common agricultural practices, since they remained in good condition throughout the cycles under the meteorological conditions, not compromising the crop development. However, as seen in muskmelon 3rd cycle, Agrobiofilms from 11 to 15 µm are not adequate to be used in fields with history of high infestations of Cyperus rotundus L. since this weed is highly resistant to herbicides and it leads to films tearing.
From the soil monitoring and in relation to physical and chemical characteristics all the parameters analysed after Agrobiofilms incorporation, showed no differences induced by mulches biodegradation along the monitoring period. In relation to temperature and WVC, it was seen that in open field conditions, the soil under biodegradable mulches tend to have a lower temperature and a higher humidity. Nevertheless, in the case of greenhouses, the water volume content and temperature of the soil depended on the type of film, grouping these in Agrobiofilms with a very similar or even higher content than PE and others with lower content. The influence of these biodegradable mulches in the water volume content in the soil must be deeper studied in order to assess if these films lead to water saving in irrigation, in open field condition. Regarding the complementary study of interaction between mulches and soil disinfection, the results from the analysis of pathogens and chloropicrin in soil and germination test after disinfection, suggested that the different films (PE and Agrobiofilms) had a similar behaviour to the applied product.
Combining all the results from soil monitoring, crop yield, pests and diseases and mulch performance in muskmelon, the Agrobiofilm with the best results was Agrobiofilm 15 µm black 100 % virgin and it is the one that we would recommend for this crop and theses edapho-climatic conditions or in similar ones.
For bell-pepper production, the mulch choice must be done accordingly to the objective. The range of Agrobiofilms tested in bell-pepper, allowed us to identify which mulch is more adequate for each of these objectives. Concerning production, best results were obtained in Agrobiofilm 12 µm black 100 % virgin and Agrobiofilm 17 µm black with recycled materials. Concerning quality parameters they revealed that the best results were obtained with Agrobiofilm 17 µm black 100 % virgin and Agrobiofilm 17 µm silver/black 100 % virgin. However, for industrial processing the film selected is Agrobiofilm 17 µm black 100% virgin, since the quality parameter pulp thickness has a great importance.
For the bell-pepper crop, the challenge was to adapt the use of mulch films to mechanical harvest once it is not the traditional practice. As in other crops where mechanical harvest was introduced (e.g. processing tomato), PE mulching is not used since interferes with harvest implement. In this case it is interesting to point out that Agrobiofilm 12 µm black 100 % virgin, had a very good performance (both in production and mechanical properties – initially in good conditions and sufficiently degraded at harvest time) and it could be economically very promising.
For strawberry, in Portugal and especially in open field, and according to all the parameters monitored, Agrobiofilm 18 µm black 100 % virgin had the best performance among all the modalities tested and it would be the mulch selected for this crop under these edapho-climatic conditions or in similar ones.
In Spain, in greenhouses, from all the parameters monitored along the project and from all the mulches tested, we can propose a range of biomulch films that can be suitable to Andaluzia edapho-climatic conditions or identical ones: Agrobiofilm 18 µm black with recycled materials, Agrobiofilm 20 µm silver/black 100 % virgin, Agrobiofilm 18 µm black 100 % virgin and Agrobiofilm 20 µm black with recycled materials. Attending to soil characteristics, we think that the mulches with higher thickness are more adequate to soils with higher content of sand.
In relation to the mulches with additives, Agrobiofilm 20 µm black 100 % virgin with 20 % filler can be commercially very interesting since it had good agronomic results and the cost could be significantly lower to the end user.
The results of respirometric tests confirm that the rate of biodegradation of Agrobiofilms is correlated with soil organic matter content. The biodegradation results are very encouraging since it is expected that around 90 % of biodegradation could be achieved in less than one year, in soils with loamy texture and O.M.=2.5 % or similar. More tests should be made to verify the biodegradation behaviour in soils representatives of the regions most adequate for the use of mulch in Portugal and Spain.
As a global conclusion and taking into account all the results obtained along this project, we can say, with a high level of confidence, that Agrobiofilm mulches are viable substitutes to PE, in Portugal, Spain and other countries with similar edapho-climatic conditions and agricultural practices.
Perennial crops (Vines)
From the observations made in both trials 1 and 2 from 2010 to 2012, it can be concluded that all the biodegradable mulch films tested in the project are unable to remain intact in the field more than 5 months under Mediterranean climate conditions. Films deterioration is related to their high sensitivity toward UV, which can be considered as the major ageing factor for mulch films in conditions of use. This statement is consistent with previous results who also observed a similar early deterioration of Mater-Bi® mulching films (NF grade) in vineyards in Tuscany (Italy).
In spite of the early deterioration of the biodegradable material, mulching has a noticeable positive effect onto the vine growth starting from the first growing season and enabling one year earlier production with significantly higher fruiting yields at the first harvest (August 2011, September 2012) in comparison with un-mulched vines. During the three growing seasons after planting, vines initially grown with biodegradable films (whatever the film composition; Mater-Bi®, PPC/PBAT or PLA/PBAT and thicknesses; 25, 40 or 70micron) and PE mulches were both more vigorous and productive than un-mulched ones, with a similar behaviour in terms of vegetative growth and production. In addition, root development appears to be favoured in the case of the biodegradable mulch treatment compared to PE and bare soil treatments. Thus, despite the early loss of integrity of all the biodegradable mulch films tested, which occurred before the end of the first crop cycle, it is worth noting that the mulch-enhanced effect on vine growth is still noticeable during the second and third crop cycles.
This suggests that the presence of mulch film at the critical early stage of growth would be as efficient as a permanent mulching, i.e. it allows the plant to grow fast enough to reach economically significant fruiting production, in contrast with un-mulched vines. Based on those results, the long-term stability of PE appears excessive, the material lifespan required for mulching application in the case of vineyard being probably around 4-5 months.
Regarding the becoming of the biodegradable mulch films after usage, field observations together with burying tests carried out in field indicate that their soil assimilation is slow but possible mainly due to the film physical degradation induced by UV light. Biodegradation tests (through respirometric measurements) undertaken in parallel at laboratory scale according to the NFU 52-001 standard enable to validate the ability of Mater-Bi® (CF04P grade) films to biodegrade in less than 2 years.
The present study shows that in spite of their early loss in integrity, biodegradable mulch films such as Mater-Bi® (CF04P grade) constitute an environmentally friendly alternative to the currently used polyethylene film. Indeed, they fulfil the requirements of vineyard mulching and its correlated farming practices i.e. remain intact in the field long enough to provide its expected positive effects on the crop, and biodegrade at the topsoil afterwards. At the economical point of view, even if more expensive than PE (about three times more), the cost of Mater-Bi® mulch film (40micron thick) is largely compensated by the return from sale of the earlier harvest without considering savings related to man-work require to remove PE film residues at the end of the crop.
The environmental performance of Agrobiofilm versus alternatives was evaluated using life cycle assessment (LCA) as a tool. Impact categories considered were global warming (GWP), non-renewable energy use (NRE), eutrophication (EP) aquatic and terrestrial, and respiratory inorgan-ics. As shown in the table, the LCA conducted for bell pepper shows that the environmental perfor-mance of the crop produced with the use of either PE much film or Agrobiofilm was improved from that produced without the use of the films.
The comparison between the use of Agrobiofilm and the use of PE in the three annual crop pro-duction systems, showed that the advantage of Agrobiofilm over PE is a reasonable reduction in non-renewable energy use, whereas very little or no advantage is found regarding the other impact categories (global warming, eutrophication and respiratory inorganics).
For vineyards, a perennial crop, the assessment was based on the first two years production. It shows that there is an improvement in eutrophication when applying mulch films to soil as op-posed to leaving the soil bare, whereas no improvement is found regarding the other impact cate-gories. This was due to a markedly higher grape yields when using much film in particular that the first harvest could take place one year earlier than with bare soils. The environmental impact of using Agrobiofilm or PE will depend very much on how the two films impact on the yield in the longer time perspective. Worth mentioning is that biodegradable mulch films seems to stimulate a better root development of vines (with more vigorous and deeper roots), which might improve the persistence of the grape yield over the coming years of production. If this will be the case, this would lead to a superior environmental performance of the ABF over the PE on a per kg grape basis.
Potential Impact:
The purpose of dissemination activities throughout the project was firstly to raise awareness for the potential farmland environmental pollution across Europe caused by the extensive use of plastic in agriculture activities year after year. Secondly, the objective was to inform that new products, such as biodegradable & compostable plastics, are valid alternative solutions, guaranteeing produce quality and yield output, by naturally controlling pest and diseases thus reducing the usage of harmful chemicals and in compliance with EU regulations. Finally, it was important to keep Agrobiofilm project in the limelight and at the same time to keep the different stakeholders informed of work in progress.
Our current objective is to disseminate project results and to hopefully build success stories for each analyzed crop that can be used as solid case studies, generating more interest and to be a starting point for further developments.
We will be using a variety of tools and communication platforms in order to spread the message to a wide target audience, identified below as stakeholders, and possibly turn some into champions of this new solution and hopefully our brand.
The message should be in accordance to Agrobiofim’s value proposition which is: “to offer a product that substitutes conventional Polyethylene mulch films by biodegradable & composting mulch films, customized to specific crops and region, with no loss in quality and produce yield output, by naturally controlling pests thus allowing farmers to reduce the usage of harmful chemicals, and in the end it will naturally soil composts in compliance to EU regulations without further costs and environmental impacts.”
Throughout the entire project we engaged with our stakeholders by using a multiplicity of tools and platforms, but which can be summarized as follows:
Internal audiences: 600 hrs of skype meetings; the agrobiofilm.eu web page; 5 group meetings (3 in Portugal, 1 in France and 1 in Denmark).
External audiences: 68 articles published in the press (25 in Spain, 41 in Portugal and 2 in France, 42 in specialized media, 26 in national media); 3 radio programs (2 in Spain - one in a national station and the other in a regional station broadcast to the South of Spain) and one 43-minute piece broadcasted in a national Portuguese station; TV airtime, totaling 9 minutes of national broadcast - 2 in Spain (http://www.youtube.com/watch?v=b_ruhPAmI-Y)- 2 in Portugal(http://www.rtp.pt/play/p140/e23054/radar-de-negocios; http://www.agrobiofilm.eu/pt/recorte_de_imprensa/244); 5 Master thesis diuscussed and approuved in Instituto Superior de Agronomia (ISA) – Portugal on bio plastics.
Regarding internation conferences/congress: SILVEX, invited speaker both at Ramiran 2010 (http://www.ramiran.net/doc10/RAMIRAN%20FINAL%20PROGRAMME_2010.pdf) and 28th International Horticultural Congress - IHC Lisboa 2010); ISA, invited speaker both at Sardinia 2011 (http://www.sardiniasymposium.it/sardinia-symposium-edition2011.aspx) and 2nd Symposium on Horticulture in Europe (https://colloque4.inra.fr/she2012); UM2-IATE/SILVEX invited speaker at GiESCO 2013 (http://www.fc.up.pt/giesco2013/PROGRAMA_FINAL.pdf).
At this stage, for the next months several activities are already confirmed:
•Aug 2013 – ISA and ADESVA participation with 3 poster communication at the VII Congreso Ibérico de Agroingeniería y de Ciencias Hortícolas (http://www.sechaging-madrid2013.org/);
•Oct 2013 – UM2-IATE participation in the BIOPOL 2013 as invited speaker (http://www.biopol-conf.org/);
•Sept 2013 – An interview with Profs. Antonio Monteiro and Elizabeth Duarte, unveiling major Agrobiofilm project results will be published at most widespread Portuguese VIDA RURAL (http://www.vidarural.pt/news.aspx?menuid=8&eid=7475);
•Sept 2013 - To publish a paper in the Technical/Scientific Agricultural magazine AGROTEC (http://agrotec.pt/?cat=42);
•Sept 2013 – To held a TV interview together with the stakeholder MONLIZ (http://sicnoticias.sapo.pt/programas/economiaverde/ ). Part of the program will be recorded at the commercial farm using Agrobiofilm silver/black in pepper.
•Sept 2013 – To distribute a project handbook “Development of enhanced biodegradable mulching films for Mediterranean horticulture and viticulture”, in 4 languages that will be distributed- given to a pre-selected stakeholder audience;
•To distribute the book for free in the project web page;
•To distribute the DVD with project main results and case studies targeted to farmers cooperatives and Producers organizations;
•To keep a continuous communication activity by delivering regular articles in regional and national press to attract the attention of general audience;
•To organize meetings for different levels of stakeholders to promote international networking and knowledge sharing about product development. Prepare brochures, flyers and other printed materials to reinforce the message;
Agrobiofilm® name and logo are already registered and will be used as commercial name for the Southern Europe market. The name visibility achieved throughout the project reaching different stakeholders, mainly trough a widespread of disseminations activities, is an important asset that should be used and will help in commercialising our products.
Regarding economic impact in the 3 SMEs (BIOBAG, SILVEX, ICSE), and in hard numbers the SME’s objective for the next 5 years is to have a joint turnover of M€56.458 with a total profit of M€8.688 proportionally divided according to RTD invoiced project share.
List of Websites:
www.agrobiofilm.eu
