Plastics in Agriculture

Center for Refining and Petrochemicais Research institute King Fahd University of Petroleum and Minerals Dhahran, Saudi Arabia 

Agriculture, horticulture, and related areas of plastics applications consume 2,250,000 tons/year of plastics worldwide. 

Plastics and the Environment, Edited by Anthony L. Andiady. ISBN 0-471-09520-6 2003 John Wiley Sons, Inc. 

Linear low-density polyethylene (LDPE) is the most important polymer, followed by (high-density polyethylene) HDPE. According to Gemaud, western Europe consumes 570,000 tons/year of agricultural LDPE, of which 350,000 tons have been used in films and tubings. 

The European Union (EU) countries use 160,000 tons in transparent crop covering, 148,000 tons in black silage film, 60,000 in transparent mulch films, and around 33,000 in stretch films [44]. 

Mulch (soil cover) is used in arid and semiarid zones to conserve water used in irrigation (Li et al, 2008). Plastic mulch is lightweight and nonporous and is a good thermal insulator, serving the role particularly well (Liu et al., 2009). The polyethylene (LDPE) and PVC films keep the soil temperature high during cold season and reduce the evaporation of soil water (Li et al., 2013) allowing economical drip 

FIGURE 5.3 Plastic films used as mulch in agriculture. 

TABLE 5.5 Greenhouse Glazing Materials and their Characteristics 

Source Data from Both (2008) and Eugene A. Scales Associates, Inc. (2003). The higher the R-value, the better the material is as thermal insulation. Photosynthetically active radiation. 

FIGURE 5.4 Main uses of plastics in building applications. Source Drawn from data in Cousins (2012). 

Musk melons (per 7 plants) New Brunswick/Bare ground Mulched 62.73 92.64 47 

In addition to the large quantities of black plastic hay-wrap referred to above, which are discarded in the fields and farmyard, very large amounts of polyethylene and polypropylene are used in agricultural packaging of feedstuffs and fertiliser sacks. In spite of the fact that some of this is recycled and farmers find secondary uses for some of it, much of it finds its way into rivers and ditches where it degrades very slowly. This is the environmental down-side of plastics packaging. 

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Davos, 14th-18th March 1994, paper 69. 8(13) PLASTICS IN AGRICULTURAL APPLICATIONS MECHANICAL RECYCLING VS ENERGY RECOVERY Fernandez A P ANAIP... 

Polymers, J.C. Gamaud, International Committee for Plastics in Agriculture. 

Applications of plastics in agriculture and horticulture and technical and environmental requirements for products used in these sectors are examined. Italian standards relating to the use of plastics in these applications are reviewed, and statistics are presented for Italian, West European and world consumption of plastics in agriculture in 1995. 

Transition metal prooxidants cause problems during both the manufacture and use of plastics products. Firstly they catalyse rheological changes in the polymer during processing and reduce shelf-life before use. Secondly it is difficult to control the induction time to photooxidation. It will be seen below that control of peroxidation is essential to the application of degradable plastics in agriculture. 

Table 5.1 Usage of plastics in agriculture (%of otal consumption )...

States in 1990 is shown in Table 7-4. Other countries use more plastics in agriculture. 

In conclusion, a solution to waste treatment by self-degradation of plastics has not been favored at least for the packaging industry. However, it has been successfully implemented for selected controlled-life plastics in agriculture (mulching). It is also a possible solution for marine debris, plastics in release control of fertilizers and pesticizers, biomedical applications, and diapers. Converting to polymers which are soluble in selected solvents may also permit some special treatment. 

P. Dilara and D. Briassovlis, in Proceedings of the International Congress for Plastics in Agriculture (CIPA), Tel Aviv, Israel, 9-15, March, 1997. 

DN. Buttrey, Plastics in Agriculture and Horticulture, Platics Today , 47, ICl, Welwyn Garden.City, UK, 1974... 

P.Dubios, Plastics in Agriculture , Appl Sci Publ, London, 1978... 

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