Microbial Agents Promoted to Reduce Use of Chemical Fertilizers and Non-Point Source Pollution

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In response to Europe’s new green policy “Farm to Fork”, the EPA is urging farmers to use environment-friendly pest control technology and cut down the use of agrochemicals and antibiotics. Not only will doing so help cut down on the cost, it will also increase the yields and profits, reduce water body pollution, and improve reservoir water quality.

The EPA explained that excessive use of agrochemicals is one of reasons non-point source pollution occurs in water bodies. Research shows that only 20-50% of spread fertilizers are absorbed by crops, while the rest causes soil deterioration. The leftover fertilizers are also washed by storms into water bodies and cause excessive growth of algae, upsetting the biological equilibrium in the water. Particularly, pollution from nutrients like nitrogen and phosphate can lead to eutrophication in reservoirs and water sources. Furthermore, insecticides and herbicides are toxic, either acutely or chronically, to aquatic organisms.

The EPA mentioned that agricultural non-point source pollution is mainly controlled through source control or structural best management practices (BMPs). Structural BMPs like manmade wetlands, grassed swales, and vegetated buffers, as well as multi-soil layering are able to intercept rainstorm water at the early stage and reduce the amount of fertilizers and pesticides that enter water bodies. However, source control, which involves reducing the use of fertilizers and pesticides or more reasonable use of them, is more effective. But farmers might worry that reducing fertilization lowers crop yield and be reluctant to take this approach. Therefore, promoting innovative green pest control technologies to encourage farmers to reduce the use of agrochemicals will not only lower the cost of fertilizers and pesticides, it will also increase crop yields and reduce water body pollution at the same time.

Microbial agents are more environment-friendly and able to increase soil absorption of both chemical and organic fertilizers, leading to more fertile soils and less dependency on chemical fertilizers. On 3 June 2011, the Council of Agriculture (COA) announced a list of Microorganisms Identified as Safe Microbial Fertilizer Species, based on which fertilizer enterprises are able to register microbial fertilizers. To date, 18 enterprises have registered 57 brands of microbial fertilizers. Since 2017, microbial fertilizers have been covered by government subsidy programs, with up to NT$5,000/acre. Moreover, the COA has been actively carrying out programs that utilize environment-friendly agricultural resources and commissioning relevant organizations to assist in promoting agricultural microorganisms such as photosynthetic bacteria.

There have been successful examples of organic farming utilizing microbial agents: lemons from Jen Shin Organic Farm, dragon fruits from Rainbow Jade Eco-Farm, guavas from Diving Coach Guava Farm, and wax apples from Chuan Chi Education and Leisure Farm. By mixing microbial agents with fertilizers, these farms have reduced fertilizer use by 32-88%, saved on the cost of fertilizers and pesticides by 29-88%, and produced higher quality crops with a 20-67% yield increase, all leading to much higher profits.

Annual use of chemical fertilizers in Taiwan roughly amounts to 1 million metric tons. With the successful experiences above, use of microbial agents in 30% of total farmlands can result in lowering use of fertilizers by 100,000 to 260,000 metric tons and saving on costs by NT$950 million to NT$2.47 billion. It will also greatly benefit the protection of water quality in water bodies and reservoirs. For instance, use of microbial agents in 80% of total farmlands can possibly turn the eutrophication status of Shihmen Reservoir from mesotrophic at the current moment to oligotrophic.

Responding to the call of Europe’s new green policy “Farm to Fork”, the EPA is striving to reduce the use of agrochemicals and antibiotics by continuing to develop green pest control technologies. The EPA will also collaborate with relevant organizations to encourage farmers to use less chemical fertilizers to reduce non-point source pollution and endeavor to establish an environment-friendly agriculture.

Excerpt from Environmental Policy Monthly, 23 (8)

Source:
Environmental Protection Administration, R.O.C.(Taiwan)
Updated:
2020-10-29
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