Historically, forested riparian buffers have been created to provide protection for aquatic organisms and aquatic ecosystem functions. Increasingly, new and existing riparian buffers are being used also to meet terrestrial conservation requirements. To test the effectiveness of riparian buffers for conserving terrestrial fauna, we conducted a meta-analysis using published data from 397 comparisons of species abundance in riparian buffers and unharvested (reference) riparian sites. The response of terrestrial species to riparian buffers was not consistent between taxonomic groups; bird and arthropod abundances were significantly greater in buffers relative to unharvested areas, whereas amphibian abundance decreased. Edge-preferring species were more abundant in buffer sites than reference sites, whereas species associated with interior habitat were not significantly different in abundance. The degree of buffer effect on animal abundance was unrelated to buffer width; wider buffers did not result in greater similarity between reference and buffer sites. However, responses to buffer treatment were more variable in buffers <50 m wide, a commonly prescribed width in many management plans. Our results indicate that current buffer prescriptions do not maintain most terrestrial organisms in buffer strips at levels comparable to undisturbed sites.

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Okinawa, Japan is known for its high marine biodiversity, yet little work has been performed on examining impacts of numerous large-scale coastal development projects on its marine ecosystems. Here, we examine apparent impacts of the construction of the Kaichu-Doro causeway, which was built over 40 years ago. The causeway is a 4.75 km long embankment that divides a large tidal flat and has only two points of water exchange along its entire length. We employed quadrats, transects, sampling, visual surveys, and microbial community analyses combined with environmental, water quality data, and 1m cores, at five stations of two paired sites each (one on each side of Kaichu-Doro) to investigate how the environment and biota have changed since the Kaichu-Doro was built. Results indicate reduction in water flow, and site S1 was particularly heavily impacted by poor water quality, with low diversity and disturbed biotic communities.

In this paper, we propose a navigation method of multiple AUVs and give a performance analysis on position estimation for a wide area survey. The key idea of the proposed method is alternating roles of the AUVs between Moving and Measuring Role (MMR) and Landmark Role (LR). AUVs in the MMR move based on the AUVs in the LR. On the other hand, AUVs in the LR keep their positions on the seabed to act as landmarks for the moving AUVs. By alternating their roles, the two groups of AUVs can observe in a wide area while maintaining a good position estimate.AUV position is estimated by mutual acoustic measurements of relative distance among AUVs and direction among them. These position measurements are fused with other on-board sensors such as Doppler velocity logger (DVL), fiber optic gyro (FOG) and depth sensor by particle filter for a robust position estimate against sensor noises and lack of measurements.We verified the performance of the method through navigation simulation based on the performance of sensors obtained during various experiments performed in a pool environment and at sea. In the simulation, the proposed method achieved a positioning error considerably smaller than dead reckoning and conventional navigation methods of a single AUV. In the proposed method, each AUV also achieved state estimation, suppressing deviation from its true position and heading due to alternating roles and evaluating outliers of positioning measurements by particle filter. Therefore, the proposed method is suitable for a wide area survey without sensor drifts and deviation from true state compared with conventional navigation methods.