Xinshe District (Taichung) is the most important bag-cultured mushrooms production area for oyster and shiitake mushrooms due to its suitable climate and environment. The annual production is as high as 2,700 tons, accounting for more than half of the total output in Taiwan. Therefore, Xinshe is also known as the "Hometown of mushrooms." In the past, used bag-cultured materials were not properly recycled and disposed of, resulting in environmental problems such as littering, on-site burial, or burning. Today, used mushroom bag-cultured materials are recycled by licensed recycling facility to reuse the mushroom sawdust, which is rich in organic matter.

Taiwan Seed Improvement and Propagation Station (TSIPS) embraces the concept of co-prosperity with the local agricultural industry and the policy of agricultural net zero by 2040. It is committed to building a low-carbon and sustainable circular field. The TSIPS annually produces 40 hectares of corn seeds to meet domestic planting needs. In addition to certified seeds, 10-20% of corn cobs are also produced, which are good filling media for mushroom cultivation. This can reduce the number of trees that need to be cut down and imported materials for mushroom bags. In addition, the corn seed cultivation field has also been tested using a new compound fertilizer developed by a cooperative factory that blends mushroom bags and livestock manure. The preliminary test results showed that the yield is good, which can further expand the use of agricultural surplus resources. Finally, mushroom sawdust can be granulated alone or mixed with tree branches and corn dregs to press biomass fuel pellets. This type of biofuel emits carbon dioxide when burned, which is balanced with the carbon dioxide absorbed by plant growth. Therefore, it is considered to be zero-emission and is a green and clean renewable energy. The TSIPS has realized the sustainable agricultural circular production field of mushroom cultivation, used bag materials recycling, and crop production through the integration of three industries in Xinshe District, and reduced carbon dioxide emissions during the production process. In the first year of the trial, it is estimated that 2,560 tons of residual materials have been successfully recycled and more than 1 ton of carbon dioxide emissions have been reduced.

The carbon emissions of the agricultural sector in Taiwan account for less than 3%, but it is the best solution to reduce carbon emissions in line with the current emphasis on "nature-based solution". Through the adjustment of production methods with the integration of industries, it can effectively respond to the development and utilization of large-scale agricultural surplus resources such as used bag materials, fruit tree branches, livestock manure, and plant dregs in the region. In the future, it will continue to expand the scale of the trial and establish a commercial operating model to promote it to other mushroom production areas. Through scientific measurement methods, it is estimated that the environmental benefits of gradually reducing carbon dioxide emissions can be realized, and the participation of agricultural net zero emission reduction will be enhanced.

Fig. 1、Mushroom Substrate Cultivation and Corn Seed Recycling Production System

Fig. 2 Mushroom sawdust recycling and reprocessing organic compound fertilizer and corn dregs pressing biomass fuel pellets