48 research outputs found
A comparative method for evaluating ecosystem services from the viewpoint of public works
Nature-based solutions (NbS), such as the implementation of environmental conservation and restoration as public works projects, require accurate and cost-effective assessments of the values related to the projects. The values should represent collective ecosystem services, individual services such as food provision and water purification, and other intangible services. To comprehensively assess such services, we proposed a novel method, which we call the comparative evaluation method. Our method is able to assess the value of each service category of an NbS project from a single questionnaire survey. Survey participants are asked to compare values of multiple services having anchoring prices. Our method determines the permissible economic value of environmental public works (PEP) in response to the quantity of service. The questionnaire results used for analysis are limited to those from respondents who made their PEP evaluation on the basis of their consideration of the appropriate expenditure of taxes. In addition, the method controls for the effect of the satisfaction that a person experiences from doing good deeds to reduce an overestimation of the values of services. Moreover, PEPs are not influenced by the respondent's annual income, age, sex, or educational background, and are based on personal values. Applying this new method, we surveyed residents of the watersheds of Tokyo Bay and Osaka Bay and evaluated nine ecosystem services. Overall, our new method is shown to be an effective method for evaluating the ecosystem services of NbS projects from the viewpoint of public works
Green port structures and their ecosystem services in highly urbanized Japanese bays
Green port structures (i.e. green infrastructure in ports and harbors) featuring habitats for marine organisms have been promoted in Japan as part of a comprehensive policy to reduce the environmental impact of ports and carry out habitat conservation, restoration, and creation. In this study, we evaluated the ecosystem services provided by green port structures in two highly urbanized bays (Tokyo Bay and Osaka Bay) in Japan. Our results show that the provision of some ecosystem services can be limited by circumstances particular to ports and other areas with restricted access. In the case of green port structures that have strong usage restrictions, for example, cultural services can only be provided if relevant authorities are prepared to conduct public events while ensuring participant safety. On the other hand, green port structures with weak usage restrictions are often equipped with incidental facilities such as parking lots and restrooms; these facilities can enhance the provision of cultural services (e.g. recreation and environmental education). Green port structures in highly urbanized bays often have usage restrictions, but their proximity to large populations means that they can potentially provide numerous ecosystem services. However, our study shows that appropriate management goals, such as protecting species and ensuring healthy habitats, are needed to maintain the value of these services in highly urbanized and eutrophic bays
Migratory movements of rhinoceros auklets in the northwestern Pacific: connecting seasonal productivities
Spatial and temporal variability in marine biological productivity may drive heterogeneity in seasonal resources available for marine animals in temperate waters. Migratory seabirds are expected to adjust their annual cycle of breeding activities and migratory movements to exploit seasonally available resources efficiently. We studied the movement and trophic position of rhinoceros auklets Cerorhinca monocerata breeding at Teuri Island, Japan Sea, during the nonbreeding and early breeding periods over 2 yr. After breeding, the auklets moved northward from the colony to the Sea of Okhotsk, where phytoplankton blooms enhanced biological productivity in autumn. The birds then moved southward to the southwestern Japan Sea (~1470 km from the colony), where major epipelagic fish and squid concentrations have been reported in winter. Stable isotope analyses suggest that the auklets fed on higher-trophic level prey, including fish and/or squid during the autumn and winter nonbreeding periods. The auklets moved northward and returned to the colony in mid-March. During the early breeding period, the birds foraged close to the colony (~380 km) on lower-trophic level prey including fish and/or krill, which were available during the spring phytoplankton bloom. The timing of the return migration does not match with the northward migration of warm-water anchovy, a profitable prey during summer, but may be related to timing the chick-rearing period to correspond with anchovy arrival. We suggest that rhinoceros auklets follow spatial and seasonal changes in prey availability by a distinctive ‘3-step’ migration (first northward, second southward, third northward) in the temperate marine system of the northwestern Pacific
Variable and complex food web structures revealed by exploring missing trophic links between birds and biofilm.Ecol.Lett
Abstract Food webs are comprised of a network of trophic interactions and are essential to elucidating ecosystem processes and functions. However, the presence of unknown, but critical networks hampers understanding of complex and dynamic food webs in nature. Here, we empirically demonstrate a missing link, both critical and variable, by revealing that direct predator-prey relationships between shorebirds and biofilm are widespread and mediated by multiple ecological and evolutionary determinants. Food source mixing models and energy budget estimates indicate that the strength of the missing linkage is dependent on predator traits (body mass and foraging action rate) and the environment that determines food density. Morphological analyses, showing that smaller bodied species possess more developed feeding apparatus to consume biofilm, suggest that the linkage is also phylogenetically dependent and affords a compelling re-interpretation of niche differentiation. We contend that exploring missing links is a necessity for revealing true network structure and dynamics
Method for the quantitative evaluation of ecosystem services in coastal regions
Wetlands, tidal flats, seaweed beds, and coral reefs are valuable not only as habitats for many species, but also as places where people interact with the sea. Unfortunately, these areas have declined in recent years, so environmental improvement projects to conserve and restore them are being carried out across the world. In this study, we propose a method for quantifying ecosystem services, that is, useful for the proper maintenance and management of artificial tidal flats, a type of environmental improvement project. With this method, a conceptual model of the relationship between each service and related environmental factors in natural and social systems was created, and the relationships between services and environmental factors were clarified. The state of the environmental factors affecting each service was quantified, and the state of those factors was reflected in the evaluation value of the service. As a result, the method can identify which environmental factors need to be improved and if the goal is to increase the value of the targeted tidal flat. The method demonstrates an effective approach in environmental conservation for the restoration and preservation of coastal areas
Species traits and geomorphic setting as drivers of global soil carbon stocks in seagrass meadows
Unidad de excelencia María de Maeztu CEX2019-000940-MOur knowledge of the factors that can influence the stock of organic carbon (OC) that is stored in the soil of seagrass meadows is evolving, and several causal effects have been used to explain the variation of stocks observed at local to national scales. To gain a global-scale appreciation of the drivers that cause variation in soil OC stocks, we compiled data on published species-specific traits and OC stocks from monospecific and mixed meadows at multiple geomorphological settings. Species identity was recognized as an influential driver of soil OC stocks, despite their large intraspecific variation. The most important seagrass species traits associated with OC stocks were the number of leaves per seagrass shoot, belowground biomass, leaf lifespan, aboveground biomass, leaf lignin, leaf breaking force and leaf OC plus the coastal geomorphology of the area, particularly for lagoon environments. A revised estimate of the global average soil OC stock to 20 cm depth of 15.4 Mg C ha−1 is lower than previously reported. The largest stocks were still recorded in Mediterranean seagrass meadows. Our results specifically identify Posidonia oceanica from the Mediterranean and, more generally, large and persistent species as key in providing climate regulation services, and as priority species for conservation for this specific ecosystem service
Structure of marine ecosystem under fast sea-ice: insight from stable-isotope analysis
第3回極域科学シンポジウム/第34回極域生物シンポジウム 11月26日(月) 統計数理研究所 3階セミナー
Seasonal change in the diet of Adélie Penguins: insight from stable-isotope analysis
第2回極域科学シンポジウム/第33回極域生物シンポジウム 11月17日(木) 統計数理研究所 3階リフレッシュフロ
The Future of Blue Carbon Science
The term Blue Carbon (BC) was first coined a decade ago to describe the disproportionately large contribution of coastal vegetated ecosystems to global carbon sequestration. The role of BC in climate change mitigation and adaptation has now reached international prominence. To help prioritise future research, we assembled leading experts in the field to agree upon the top-ten pending questions in BC science. Understanding how climate change affects carbon accumulation in mature BC ecosystems and during their restoration was a high priority. Controversial questions included the role of carbonate and macroalgae in BC cycling, and the degree to which greenhouse gases are released following disturbance of BC ecosystems. Scientists seek improved precision of the extent of BC ecosystems; techniques to determine BC provenance; understanding of the factors that influence sequestration in BC ecosystems, with the corresponding value of BC; and the management actions that are effective in enhancing this value. Overall this overview provides a comprehensive road map for the coming decades on future research in BC science
サシツ ヒガタ ニ オケル テイセイ ビセイブツ ノ エイヨウエン ジュンカン ニ ハタス ヤクワリ
京都大学0048新制・論文博士博士(農学)乙第10818号論農博第2396号新制||農||835(附属図書館)学位論文||H13||N3600(農学部図書室)UT51-2001-R797(主査)教授 中原 紘之, 教授 坂本 亘, 教授 内田 有恆学位規則第4条第2項該当Doctor of Agricultural ScienceKyoto UniversityDA