The Faculty of Agriculture, Universitas Gadjah Mada (Faperta UGM), once again presented an international guest lecture as part of a workshop entitled “Land Use and Management Changes and Organic Rice Farming in Shonai, Japan.” The event featured Prof. Weiguo Cheng from Yamagata University, Japan, as the keynote speaker.
The lecture was held at the Prof. Harjono Danoesastro Auditorium on Thursday, March 12, 2026, from 08.00 to 09.45 WIB. A total of 313 participants attended the event, including students, researchers, academics, and representatives from the Agrotechnology Innovation Center (PIAT) UGM who share an interest in sustainable agriculture and land management.
In his presentation, Prof. Cheng outlined the long-term research journey on organic rice farming conducted at the Yamagata University Farm, Takasaka, which has been ongoing since 2007. This research focuses on innovations in weeding methods to sustain organic rice productivity. Experimental findings revealed that:
- Weeding frequency significantly affects yield. Eight times weeding (8WF) produced the highest rice ear biomass, though not significantly different from six times weeding (6WF).
- Two times weeding (2WF) already enhanced nitrogen (N) uptake in rice compared to weeds, but more intensive weeding (8WF) significantly improved N uptake and rice growth.
- More frequent weeding reduced weed biomass while increasing rice biomass and N uptake, up to threefold compared to plots without weeding.
These findings highlight the importance of innovation in weed management to support organic rice productivity while maintaining agricultural ecosystem sustainability. In addition, Prof. Cheng introduced a second research project focusing on the long-term impacts of organic rice farming on Japanese Andosols. Key results include:
- Carbon (C) and nitrogen (N) stocks, as well as their mineralization potentials, are higher under organic farming systems compared to conventional methods.
- During the first 4 – 5 years, the effects of organic farming were not significant, marking a transition period.
- Significant changes in carbon decomposition and nitrogen mineralization potentials emerged after 8 – 9 years.
- C and N stocks showed clear differences only after more than 12 years of continuous organic farming practices.
These results demonstrate that organic farming not only influences rice productivity but also contributes substantially to long-term soil health. Consequently, the research reinforces the argument that organic farming is a sustainable strategy to preserve agricultural ecosystems while advancing the achievement of the Sustainable Development Goals (SDGs).
The Faculty of Agriculture UGM emphasized that this event not only strengthens international academic networks but also provides new insights for the academic community in developing environmentally friendly agricultural systems. The guest lecture series directly supports several SDG targets, including SDG 4: Quality Education, SDG 15: Life on Land, and SDG 17: Partnerships for the Goals.
Author: Beny Nabila Happy Fauziah
Editor: Tantriani
Documentation: Media Unit, Faculty of Agriculture UGM