This series introduces people (person or group) with outstanding achievements in mangrove-related fields.
Activities can be scientific findings, practical field procedures, photos, short stories, discovery of new or rare species/hybrids, etc.

Please recommend someone or yourself to the ISME Secretariat for selection by the Editorial Board.

New Findings!
Diazotrophic communities of nitrogen fixation in rhizospheres of Rhizophora stylosa

Outline: The soils of tidal flats, on which mangroves grow, are often depleted in nitrogen because the nitrogen-containing litter is washed offshore during ebb tides. Under such site conditions, it remains unclear how mangrove plants acquire the nitrogen required to support their vigorous growth. The present paper (Inoue et al., 2020) discovered that the rhizospheres of mangrove trees dominated by Rhizophora stylosa accumulate diazotrophic communities having high soil nitrogenase activities. As trees grow and develop greater root biomass, the diazotrophic communities perform greater nitrogen fixation, which is pertinent for plant growth. The mutualistic relationship between mangrove roots and diazotrophs seems to benefit the mangroves by enabling them to establish and colonize open tidal flats. This study on R. stylosa was conducted in the northern part of Iriomote Island, one of the southernmost islands of Japan.

Reference: Tomomi Inoue1, Ayako Shimono2, Yasuaki Akaji1, Shigeyuki Baba3, Akio Takenaka1 & Hung Tuck Chan3. Mangrove–diazotroph relationships at the root, tree and forest scales: diazotrophic communities create high soil nitrogenase activities in Rhizophora stylosa rhizospheres. Annals of Botany 2020; 125(1): 131–144 (Editor’s Choice). 1National Institute for Environmental Studies (NIES), 16-2 Onogawa Tsukuba, Ibaraki 305-8506, Japan. 2Department of Biology, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan. 3International Society for Mangrove Ecosystems (ISME), University of the Ryukyus, Nishihara, Okinawa 903-0129, Japan.

Lead author: Dr Tomomi Inoue is a Senior Researcher of the Center for Environmental Biology and Ecosystem Studies, at the National Institute for Environmental Studies, Tsukuba, Japan. Dr Inoue has six publications in 2019 and has 188 citations in Google Scholar. She is also a Life Member of the International Society for Mangrove Ecosystems (ISME) with Headquarters in Okinawa, Japan, and the Project Leader of Tropical Coastal Ecosystems Portal (TroCEP URL:, a website that provides information on tropical coastal ecosystems with world distribution maps, plant species lists and ecosystem functions.