Plasticulture (plastic in agriculture) in Australia uses an estimated 90,800 tonnes of plastics in agriculture each year but only 7% is recycled. Plastic is used in every kind of agriculture and horticulture around the world today. Some sources of plastic waste produced by farms include:
- plastic mulch film
- plastic wrap
- product containers
- planting containers
- crop tunnels
Costs to remove and dispose of plasticulture waste can be high. Farmers are tempted to burn or bury plastic waste. However, plastic residue in soil can decrease soil porosity and air circulation, change microbial communities, and potentially lower farmland fertility. Fragments of plastic film may release potentially carcinogenic phthalate acid esters into the soil, where they can be taken up in vegetables and pose a human health risk when the food is consumed. Film fragments left in fields can also accumulate pesticides and other toxins applied to crops. Plastic items, fragments, and microplastics enter soil, air, and waterways and can eventually end up in the ocean.
While it has been estimated that in 2014 there were over 250,000 tonnes of plastic floating out at sea, a 2020 study found this figure could be hugely underestimated by several hundreds of thousands to a few million metric tons. Plastic also accumulates on beaches and inshore waters where it degrades further only to be released again out to sea. Thus, there is a time lag between when plastic leaves land and later reaches the deeper ocean. Tangaroa Blue Foundation Database alone has recorded over 1250 tonnes and 15.5 million items of marine debris on Australia’s beaches and Islands. Most of this is plastic with hard plastic bits and pieces at number one and soft plastic film in the top ten.
The Great Barrier Reef Marine Park Authority lists plastic marine debris as one of the major threats to the reef and suggests action by community, industry and government to choose sustainable options, minimise waste and undertake stewardship activities. Plastic is life-threatening for marine species. Impacts include entanglement, ingestion, toxic exposure, disease and death. Marine debris negatively affects all species of sea turtle and more than half of all known species of marine mammal and seabirds. Plastic waste increases the risk of coral disease outbreaks and consequent damage to reefs, as well as the loss of fisheries and coastal protection. Microplastics are consumed by coral posing further risks to coral health.
The Reef Guardian Program is a hands-on, community-based approach that includes schools, local government, fishers, farmers and graziers who have pledged to make a real difference to the health and resilience of the Reef.
Farmers can reduce contamination of our soil, water, food and air, by:
- Reducing plastic use
- Responsible disposal
- Keeping plastics out of soil and waterways
- Use biodegradable and compostable alternatives
- Practice dry farming and alternative irrigation techniques