Organizer: Shota Nishijima (National Research Institute of Fisheries Science) and Misako Matsuba (Japan Agency for Marine-Earth Science and Technology)
企画者：西嶋翔太（中央水産研究所）・松葉史紗子（海洋研究開発機構）
10月7日｜14:00〜16:00 ｜B会場
We spend our lives receiving various benefits from oceans. A wide variety of fishes and shellfishes provides important protein sources to us. Many people enjoy recreational fishing and diving in coral reefs. Although we may pay less consciousness in our daily lives, seagrass beds in coastal areas play a role in absorbing carbon dioxide emitted from human and industry activities, which contributes to the mitigation of global warming. These are all marine ecosystem services that support and enrich our lives, but their sustainability is now threatened by anthropogenic impacts such as overexploitation and environmental change.
In this symposium, we will introduce the latest knowledge of the evaluation and management of marine ecosystem services to recognize their values and discuss future prospects. Presenters of this symposium will give a talk on provisioning, regulating and supporting services, and their integrated relationships. We welcome to discuss among our participants toward conservation and sustainable use of marine ecosystem services.
Shota Nishijima (National Research Institute of Fisheries Science)
Malin Pinsky (Rutgers, The State University of New Jersey)
The same ecological and evolutionary processes operate in marine and terrestrial environments, and yet ocean life thrives in a fluid environment that is dramatically different from what we experience in air. The ocean is, in effect, a 1.3 sextillion liter water bath with muted thermal variation through time and space and limited oxygen. In this talk, I will trace what I see as some of the important consequences for fish and fisheries, including a number of striking contrasts and similarities to patterns on land. Most marine animals have evolved narrow thermal tolerances and live close to their upper thermal limits, which makes them surprisingly sensitive to even small changes in temperature. I will show that fish and other marine animals have responded rapidly and often quite predictably to temperature change and temperature trends, across time-scales from seasons to decades. Finally, I will link these rapid ocean changes to their impacts on fisheries and on people. The tight feedbacks and lagged responses between fisheries and ocean dynamics create both immediate impacts and complex dynamics that can complicate management efforts. The magnitude and extent of climate impacts on fisheries imply the need for a new era of climate-ready management more fully informed by environmental dynamics and long-term trends.
*Momoko Ichinokawa and Hiroshi Okamura (National Research Institute of Fisheries Science)
In Japanese fisheries stock management, target stock abundance level based on maximum sustainable yield (MSY) has not been estimated or utilized owing to historical critiques on MSY concept itself. However, in response to worldwide accumulation of successful practices on stock rebuilding with explicit management targets based on MSY, Fisheries Agency declared a new management policy to incorporate management target based on MSY or MSY proxies into its management objectives in June, 2018. This presentation introduces estimates of MSY reference points for Japanese major fisheries stocks and compared the average stock status with those in the world’s other regions. We found that the status of Japanese domestic fisheries stocks is comparable with the worst among the other world’s regions with well-developed management systems. However, this fact concurrently means that Japanese fisheries have a great potential to increase their yields and profits in future by introducing appropriate stock management to rebuild our fisheries stocks. We also approximately estimated the extent of the “great potential” under different ecological assumptions and harvesting strategies and examined whether such increase of total yield is feasible in context of marine ecosystem function.
*Hirotada Moki1, Akio Sohma2, Hisashi Shibuki3, Kenji Toyoda3, Anirban Akhand1, Kenta Watanabe1, Tatsuki Tokoro1,4, Tomomi Inoue5, Hiroya Yamano5, Masayuki Banno1, Yasuyuki Nakagawa1,6, Hiroyuki Matsuda7 and Tomohiro Kuawe1 (1.Port and Airport Research Institute, 2.Osaka City University, 3.Mizuho Information)
Coastal ecosystems can play a role in climate change mitigation through effects such as CO2 absorption. Japanese coastal ecosystems can be especially effective because Japan has sixth length of coastal line in the world. The utilization of numerical models is the one of the appropriate way to accurately quantify and predict the roles. The mitigation effects can be facilitated by CO2 uptake by net primary producers such as seagrasses, seaweed, mangroves and zooxanthella in coral reef. In this study, we applied a new ecosystem model that incorporates the biogeochemical processes of seagrass and seaweed meadows, tidal flats, lagoons, mangroves and coral reefs. We simulated CO2 fluxes between air and the ecosystems in the representative coastal areas in Japan. In the future prediction, we selected two scenarios of representative concentration pathways, low emission (RCP2.6) and high emission (RCP8.5), adopted in IPCC 5th Assessment Report and compared the model results in 2010 and 2100. We used output of HadGEM2-ES from CMIP5 models as the boundary condition for air and offshore sea. Our model results showed that the seaweeds absorbed CO2 more than other ecosystems in the whole vegetated areas. We will also present the result of carbon cost in each ecosystems calculated using J-credit.
Misako Matsuba (Japan Agency for Marine-Earth Science and Technology)
Marine and coastal ecosystems have provided us with cultural ecosystem services such as beach recreation, recreational fishing, and aesthetic or spiritual spots. Cultural ecosystem services have attracted attention in recent years from the viewpoint of improving psychological well-beings of residents as well as providing economic values through sightseeing and recreation. Seascape, particularly for coastal zone is likely to face intensive development for human use due to alluvial plain. However, quantitative evaluation of cultural ecosystem services provided by seascape is not enough. In this research, I compared the relationship between the characteristics of the coastal landscape such as land use type around the coast and population density, and each cultural service type (ex. beach recreation, aesthetic sites). As a result, beach recreation sites had not only plain sandy landscapes but more accommodation facilities in the surroundings, whereas scenic spots were not necessarily located in environments with lots of accommodation facilities. In addition, the scenic spots tended to be the locations for endangered water species to inhabit. Each type of marine and coastal cultural services that people enjoy was related to different characteristics of seascape, suggesting the responses to environmental changes may be different among services.