Spartina alterniflora, a halophytic plant native to the east coast of North America and the Gulf of Mexico, grows in river estuaries and tidal flats, forming large colonies. Given that the invasion of this species often has substantial detrimental effects on local ecosystems, including the survival of benthic animals and native plants, it needs to be appropriately managed. Since 2009, S. alterniflora has been spreading into the Ohno River, which flows into in the inner region of the Yatsushiro Sea. As the Ohno River environment has obstructed access to dredging machines and thus restricted the removal of S. alterniflora, colonies of this plant have rapidly proliferated. To characterize its spreading patterns in this river, we quantified chronological changes in the area covered by S. alterniflora colonies based on a comparison of aerial photographs. The colonies were found to be distributed primarily in the intertidal zone of the Ohno River. Although the number and area of S. alterniflora colonies have increased markedly along the river estuary up to 2 km upstream, these colonies are rarely found in the upper reaches of the tidal zone, which could be attributable to the fact that large stands of Phragmites australis reed cover extensive parts of the habitat in the upper part of the intertidal zone. Nevertheless, there remain areas in the intertidal zone that are potentially suitable for further growth of S. alterniflora (i.e., bare fields), indicating that it will continue to expand its distribution along the Ohno River in the future. Continuous monitoring of the Ohno River and neighboring rivers will facilitate the early detection of this spread and thereby minimize the costs of controlling S. alterniflora growth.

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 Migratory birds are considered as vectors of infectious diseases, owing to their potential for transmitting pathogens over large distances. The populations of barn swallow (Hirundo rustica) migrate from Southeast Asia to the Japanese mainland during spring and migrate back to Southeast Asia during autumn. This migratory population is estimated to comprise approximately hundreds to thousands of individuals per year. However, to date, not much is known about the gastrointestinal microbiota of the barn swallow. In this study, we characterized the fecal bacterial community in barn swallow. Using 16S rRNA gene metagenomic sequencing analysis, we examined the presence and composition of potentially pathogenic bacteria in the fecal samples, which were collected during spring season from Osaka. The number (±S.D.) of total bacteria was approximately 2.1(±3.4)×10⁸ per gram of feces. In most samples, the bacterial community composition was dominated by families, such as Enterobacteriaceae, Pseudomonadaceae, Mycoplasmataceae, Enterococcaceae, Streptococcaceae, and Alcaligenaceae. However, no relationship was found between the bacterial community composition and geographical area in the fecal samples. Potentially pathogenic bacteria were detected at the rate of >0.1%, which included Pseudomonas spp., Escherichia/Shigella spp., Enterobacter spp., Yersinia spp., Mycoplasma spp., Enterococcus spp., Achromobacter spp., and Serratia spp. Our results suggested that barn swallow is instrumental in the transmission of these genera over large distances.

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Egg-spawning and browsing behavour of an archiannelid, Saccocirrus uchidai, were studied at a mediolittoral habitat in Oshoro, Hokkaido, north Japan. During the breeding season, May to July, in 1980 and 1981, it was occasionally observed that a number of worms came out from the interstices among coarse Shelly sands, then they spawned eggs or fed over the sediment. Timing, position and abundance for the occurrence of these behavioral phenomena displayed over the sediment were studied together with their under-sediment movement (aggregation and migration). Besides the above, the motions of egg-spawning worms were closely observed in the laboratory condition.

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北海道内で繁殖する魚食性猛禽類であるミサゴ Pandion haliaetus 成鳥と雛（各n＝1）の羽を別々に採集し，総水銀濃度を測定した．2008年に北海道北部の豊富町で採集したミサゴ成鳥の羽は5.17 µg/gであり，2016年に北海道西部の神恵内村で採集したミサゴ雛（約5週齢の死体）の羽の水銀濃度（乾重量）は1.84 µg/gであった．この結果は，これまでに日本国内外で報告されている水銀濃度値の範囲内であった．日本におけるミサゴの水銀蓄積については情報が乏しいことから，その実態解明には今後もさらなる調査を行う必要がある．

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ハイブッシュブルーベリーの'Weymouth'と'Northland'並びにラビットアイブルーベリーの'Tifblue'を供試し,温室搬入時期,GA処理および人工受粉が果粒の収穫時期,収量並びに果粒形質に及ぼす影響について検討した. 実験1. 温室搬入時期が開花,収穫時期および結果率に及ぼす影響 3品種とも,温室搬入時期が早いほど開花が早く,収穫時期も早くなった.ただし,'Weymouth'と'Northland'では,1月18日区と2月1日区では差が生じなかった.また自然受粉の温室搬入各区の結果率は露地区に比較し低かった. 実験2. 人工受粉およびGA処理が収穫時期,結果率並びに果粒形質に及ぼす影響 'Northland'と'Tifblue'の両品種とも,人工受粉区は露地区に比べて収穫日が早く,結果率も高く,また果粒の肥大が優れ,収量も多かった.この傾向は温室搬入時期に関係なく認められた.GA処理も結果率を高めたが,人工受粉区と比較し,収穫日が遅延し,果粒の肥大が劣った. 以上の結果から,山陰地方では2月上旬以降の促成栽培が可能と考えられ,その場合,訪花昆虫の利用や人工受粉等の栽培技術の導入が必要である.

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「労働の地理学」は，従来の経済地理学が企業や資本の視座に立脚していたことへの反省から，労働者の行為主体性を正当に評価するべきことを主張し，企業や資本の視座から労働者の視座へと，経済地理学のポジショナリティを転換することを目指している．資本によるフレキシブルな労働力の活用は，労働者にとってはリスクとみなされる．エンプロイアビリティは個人に帰すことのできない地理的多様性を持った状況依存的な概念として再認識され，失業や不安定雇用の原因を労働者のスキル不足に求め，労働市場への参入を動機づけようとするワークフェアの概念は，その妥当性を問われることになる．
「労働の地理学」において，労働市場は本質的に地理的多様性を持ち，社会的に調整されたアリーナであると認識される．「労働の地理学」は空間スケールを所与のものとみなさず，労働者を含めた諸主体の相互作用によって空間スケールが生み出され，それがより上位／下位の空間スケールと接合している態様を分析するのである．

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