Various aquatic ecosystems suffer from soil erosion and runoff, exacerbated by climate change. In addition to the loss of productive topsoil, this is detrimental to e.g. fishing communities and economies that depend on the marine ecosystem. While buffers along agricultural lands have been known to reduce this runoff, productive farmland would have to be given up for this cause.


Greenbelts can be designed to be ecologically and economically productive. Developing products that utilize their annual growth, for example, means that the buffer strip remains untilled, absorbing and reducing runoff, while also generating revenue. Guaranteeing this purchase can help to gain understanding from cooperating farmers and the interest of additional farmers while also funding continued conservation activities.

One of the impacts of climate change is increased soil erosion due to a combination of factors such as increases in the amount and intensity of rainfall, drought, winds, and other abnormal weather events. Erosion is detrimental, not only as the loss of productive soil, but also because the runoff of sediment and other pollutants is harmful to downstream aquatic ecosystems. Outcomes such as eutrophication due to runoff of agricultural fertilizers, or degradation of coral habitat due to runoff of fine sediments, also impact the human communities and economies that depend on these marine ecosystems.

Setting buffer zones around agricultural fields and waterways has been known to reduce such runoff. These untilled, vegetated greenbelts can physically block sediments and absorb the runoff, ameliorating the amount and quality of the water runoff. However, this practice often came at a price to farmers, who are asked to set aside farmland where they had previously grown profitable crops. In the case below, conservation work addressed this conundrum by developing an economically viable greenbelt.


Product development with a “gettou” greenbelt in Shiraho village

SINCE 2007

15 years

Shiraho village of Ishigaki, Okinawa in Japan is an agricultural and fishing community with a traditional “coral reef culture” linked to the abundant coral in the area. However, the erosion of fine soil matter of the area due to development projects and agricultural tilling has exacerbated due to the impacts of climate change. Once in the water, such particles block the sunlight and inhibit photosynthesis in the coral colonies, choking their breatheway.

Shiraho Sakana waku umi Hozen Kyogikai (Conservation association of Shiraho’s Sea of Fish)” works to protect and pass on Shiraho’s coral reef as the village’s communal asset. In addition to water quality monitoring, the organization, with WWF Japan, began installing greenbelts to buffer agricultural lands, known as the primary source of sediment runoff in the region. Native species such as “gettou” ginger and plantain that develop intricate root systems are planted around the fields of cooperating farmers, oftentimes with the participation of students and volunteers. The roots hold the soil in place and block runoff from the fields, while the planting activities provide opportunities for environmental education and community building.

Credit: Masahito Kamimura


In further collaboration with villagers of the “Shiraho Sunday Market” that produces and sells nature-based, local products, the group then developed the first products that utilize the greenbelt. These activities have since been handed over to Natsupana, a nonprofit organization established in 2012 for Shiraho’s sustainable development.

Credit: Aya Yoshida


Products that utilize the greenbelt gettou also helped with the economic viability of the project. The annual growth in leaves and flowers are harvested, purchased, and sold as teas and room sprays.  Farmers who volunteer their peripheral land for the greenbelt can be guaranteed that the plant growth would be purchased, reducing the need for tilling and other agricultural activities with potential impacts on terrestrial and marine ecosystems. Proceeds of the product sales fund further conservation activities and garner understanding and further interest in the community.