Biodegradable plastics could reduce nitrogen pollution in agriculture

By 2050, the world's population is expected to grow to around 10 billion. This increase will require us to produce food for about 1.8 billion more people. However, we face a challenge. There is less land available for agriculture due to urban development, and we must avoid cutting down more forests for farms. Using large amounts of synthetic nitrogen fertilizers can harm the environment. These fertilizers contribute to greenhouse gas emissions, soil acidification, and loss of biodiversity. They also create excess nutrients that can lead to harmful algal blooms in waterways, affecting marine life, especially around sensitive ecosystems like the Great Barrier Reef. Additionally, nitrogen pollution can lead to serious health problems, such as respiratory diseases and cancers. Farmers often find it hard to reduce fertilizer use because it could decrease their crop yields and income. One proposed solution is to coat fertilizers with plastic to slow the release of nitrogen, which could reduce waste. However, this creates another problem. The plastic breaks down into microplastics that contaminate water and soil, entering the food chain and affecting human health. In Australia, there are no regulations on the use of plastic-coated fertilizers, which are widely available. The United Nations is working towards a global treaty to combat plastic pollution, highlighting the need for safer alternatives that can lessen nitrogen pollution while still increasing agricultural output. Researchers in Australia have been developing biodegradable plastic coatings, or bioplastics, to address this issue. Recent studies showed that certain bioplastics could be broken down by native soil microbes. These microbes converted the bioplastics into harmless substances under typical agricultural conditions, and the degradation did not harm their populations. Some of these soil microbes also help produce essential nutrients for plants. The researchers are now planning further tests to see how effective these bioplastics are for fertilizer delivery in real-world settings, including commercial viability for farmers. Future research will explore how to customize the thickness of bioplastic coatings to match the release rate of fertilizers with the growth patterns of crops. By overcoming these challenges, the goal is to enhance sustainable food production while ensuring the health of people and the planet.