10:45 〜 12:15
[AOS17-P11] Material cycle model of land-based oyster farming as a model case for ecosystem cycle forecasting technology
キーワード：物質循環、海洋生態系、栄養塩、植物プランクトン
In recent years, the effect of human activities such as agriculture and aquaculture on marine ecosystems and biodiversity have been receiving heightened attention. For example, aquaculture has been observed to cause environmental deterioration in coastal areas due to the release of excrement and leftover feed from farmed fish into the surrounding environment. In contrast, there have also been cases where human activities such as the creation of seaweed beds and artificial tidelands has been shown to have a positive effect on marine ecosystems. However, further studies are needed to accurately quantify and forecast these effects.
In order to further examine these effects, we are developing ecosystem cycle forecasting technology to model and forecast changes in key components of marine ecosystems. We build on an existing model to track cycling of nutrients and waste materials derived from human activities through marine ecosystems, and simulate quantitative changes in organisms and nutrients in the ecosystem model.
In this presentation, we introduce a material cycle model for land-based oyster farming. In the land-based oyster farm targeted in this study, phytoplankton are cultured in closed containers to use as oyster feed. These phytoplankton are then fed to oysters in water tanks, generating wastewater containing leftover phytoplankton, excess nutrients (nitrogen and phosphorus) and detritus. To track the cycle of the materials in these closed water tanks, we modified a standard NPZD model (Soetaert and Herman, 2009) to contain four variables: nutrients, phytoplankton, oysters, and detritus. We conducted a comparative evaluation of simulation results and measured data. As a next step, we are planning to develop a marine ecosystem model that can simulate the impact of wastewater flowing into the ocean instead of a closed environment.
In the near future, we will expand the model scope to target human activities in primary industries such as fishery and agriculture, as well as marine development. This work will allow forecasting of future responses of marine ecosystems to human activities. We also hope to use this technology to identify potential human activities that can have positive effects on marine ecosystems encourage conservation of marine biodiversity.
In order to further examine these effects, we are developing ecosystem cycle forecasting technology to model and forecast changes in key components of marine ecosystems. We build on an existing model to track cycling of nutrients and waste materials derived from human activities through marine ecosystems, and simulate quantitative changes in organisms and nutrients in the ecosystem model.
In this presentation, we introduce a material cycle model for land-based oyster farming. In the land-based oyster farm targeted in this study, phytoplankton are cultured in closed containers to use as oyster feed. These phytoplankton are then fed to oysters in water tanks, generating wastewater containing leftover phytoplankton, excess nutrients (nitrogen and phosphorus) and detritus. To track the cycle of the materials in these closed water tanks, we modified a standard NPZD model (Soetaert and Herman, 2009) to contain four variables: nutrients, phytoplankton, oysters, and detritus. We conducted a comparative evaluation of simulation results and measured data. As a next step, we are planning to develop a marine ecosystem model that can simulate the impact of wastewater flowing into the ocean instead of a closed environment.
In the near future, we will expand the model scope to target human activities in primary industries such as fishery and agriculture, as well as marine development. This work will allow forecasting of future responses of marine ecosystems to human activities. We also hope to use this technology to identify potential human activities that can have positive effects on marine ecosystems encourage conservation of marine biodiversity.