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The amount of precipitation around the Sagami River estuary in autumn 2020 was 38% of that in autumn 2019 and this was expected to reduce the inflow of river-ater to the estuary. To estimate the effects of the decreased precipitation, the abiotic and biotic envi-ronments were measured in the estuary in January 2021 and were compared with those in De-cember 2019. The reduced precipitation clearly affected the abiotic environment. The coastal water-mass derived from river water, which was observed in December 2019, was not observed in this study. The open sea water-mass covered the estuary and the salinities measured in this study were ca. 0.4‰ higher than those of December 2019. The reduced precipitation also affected the biotic environment. The phytoplankton biomass was significantly lower and the accumulation of phytoplankton on the seafloor was not observed in this study. Corresponding to the lower biomass, the surface densities of the dominant diatom species (Skeletonema costa-tum complex) in this study decreased to ca. 40% of those in December 2019, although decreases in cell density were not observed in the dominant haptophyte species (Gephyrocapsa oceanica). The effects of lower precipitation varied from species to species, resulting in significant chang-es in the species composition of phytoplankton communities. This study showed that decreased precipitation has a marked impact not only on abiotic environments in the estuary but also on biotic ones. ; 原著 ; 2020年度 神奈川大学総合理学研究所共同研究助成論文

To obtain breeding materials for biomass crops, genetic resources of Miscanthus spp. were collected from the mountainous area of the Chubu region in October 2021. Twenty-one accessions were collected from the Gifu, Toyama, and Ishikawa prefectures, where naturally occurring Miscanthus spp. populations are found on roadsides and forests. ; 2021年11月に中部地方の山間地において，バイオマス利用を目的とする植物の育種素材としてススキ属（Miscanthus spp.）遺伝資源の探索収集を行った．岐阜，富山および石川の各県において，路傍や山林に自生していた集団を合計21点収集した． ; Figure 1点, Table 1点, Photo 22点

To obtain breeding materials for crop production, genetic resources of Miscanthus sacchariflorus were collected along the main rivers around the Tokai, Kinki, and Koshin regions in November 2020. A total of 19 clones were collected from the Aichi, Gifu, Nagano, Yamanashi, and Shiga prefectures, where naturally occurring M. sacchariflorus populations were found on riversides and riverbeds. ; 2020 年11 月に東海，近畿，甲信地方の主要河川において，バイオマス利用を目的とする植物の育種素材としてオギ（Miscanthus sacchariflorus）遺伝資源の探索収集を行った．愛知，岐阜，長野，山梨，滋賀の各県において，合計19 点を収集し，いずれも河川敷や川沿いにおいて自生集団が認められた． ; Figure 1点, Table 1点, Photo 19点

The physical and chemical conditions in the Sagami River estuary were measured during the high-temperature summer season of 2021, and the results were correlated with the distribution of phytoplankton. The results showed that thermal stratification was clearly observed from the mouth of the river to 5000 m offshore, and that saline stratification was observed in the thin surface layer from the mouth of the river to 2000 m offshore due to the inflow of fresh water from the Sagami River. The low-salinity water contains high concentrations of nitrate, which corresponds to the relatively high biomass of phytoplankton, mainly in the surface layer at 1500 m offshore. Relatively high concentrations of unconsumed phosphate remained in this water mass, indicating that phytoplankton growth in this region may be ratelimited by nitrogen nutrients. This study suggested the structure of the phytoplankton community in this high-temperature season to predict the structure after global warming in the future, and showed that measurements with improved spatial resolution were able to detect water mass structures in this area that were missed by normal resolution measurements. ; 原著2021年度神奈川大学総合理学研究所共同研究助成論文