As the conservation of biodiversity also helps preserve the benefits of the ecosystem that are reaped by humans, it is an important part of Japan's key national strategy. Also in port and harbor operations, protection of biodiversity is one of the most crucial goals, and it is expected that biodiversity will be maintained and enhanced through the restoration of intertidal flats, seagrass beds, etc. However, the concept of biodiversity is abstract yet complex. Therefore, in order to decide policies on future projects and evaluate completed projects effectively, it is necessary to find some methods through which we can clearly define what biodiversity means.

In this study, we focus on diversity indices as one of the means of defining biodiversity and aim to develop evaluation criteria that can be used to assess how various types of environmental consideration in port and harbor operations might contribute to conserving biodiversity.

As this will be the last fiscal year of this particular research item, we have organized the research findings from the past three years. We decided that the main objective of this research project is to standardize diversity indices, which are highly dependent on the extent of sampling efforts made by observers, using simple methods that are scientifically error-free yet useful enough for practical application. More specifically, we organized views on how to factor in the extent of sampling efforts made by observers, used data obtained from actual sea areas, and identified the types of diversity indices that would be suitable for port and harbor operations. Going forward, we plan to organize the findings from this research and promote the dissemination of related technical knowledge among engineers involved in port and harbor operations, while continuously developing technology and techniques that are more clearly geared toward protecting biodiversity in port and harbor operations.