Search

人工衛星等の宇宙のデータを使って地球の課題を解決するハッカソンイベントNASA InternationalSpace Apps Challenge (SpaceApps)が，2012 年より毎年開催されている．2020 年の年初より始まった新型コロナウイルス感染症 (COVID-19) の拡大を背景とし，宇宙データを使ったCOVID-19対策を行うバーチャルハッカソンイベントSpaceApps COVID-19 Challengeが急遽企画され，2020 年5 月に開催された．イベントはオンラインでの開催となり，日本では，日本地域の参加者向けに過去のSpaceAppsのオーガナイザが中心となってイベントのサポートを行った．本稿では，SpaceApps COVID-19 Challengeの開催の背景と概要，オンラインツールを活用した開催支援方法，結果と課題についてまとめる．, The NASA International Space Apps Challenge (SpaceApps) has been held annually since 2012. Space Apps is a hackathon event that utilizes satellite data to solve global issues. In response to the expansion of COVID-19, the SpaceApps COVID-19 was urgently held in May 2020. This COVID-19 event is a virtual hackathon event for COVID-19 countermeasures utilizing satellite data. In Japan, the organizers of past SpaceApps events played a role in supporting this COVID-19 event for participants in the Japanese region. This paper summarizes the background and outline, the supporting method with online tools, and the outcomes and the concerns of the SpaceApps COVID-19 challenge in the Japanese region., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA2030022006, レポート番号: JAXA-RR-20-010

乾燥地植物において夜明け前から早朝にかけて葉面上に発生する露を葉から吸収しうるのかを明らかにするため，中国半乾燥地原産の常緑針葉樹Juniperus sabinaを対象としてその鱗片葉に水を与え，前後の重量変化から吸水量を推定する実験を行った。葉の水ポテンシャルと気孔開閉が様々な葉に対し，霧吹きで水を噴霧あるいは全体を沈水して水を与えた結果，吸水前の葉の水ポテンシャルや気孔開閉などの条件に関わらず，ほぼすべての実験において葉からの吸水が確認され，吸水量は水を噴霧した葉よりも全体を沈水させた葉の方が多かった。これらのことから，葉表面から葉内への水ポテンシャル勾配を駆動力としない，気孔開口部以外の孔辺細胞やクチクラ層を経路とした吸水が行われていることが示唆された。したがって，J.sabinaは気孔を閉じている夜明け前に葉面上の露を利用可能であると考えられた。

Irregular drought has been reported to trigger general flowering (GF) in lowland tropical rain forests in Southeast Asia. We hypothesized that the interspecific differences in water uptake depth may influence the flowering frequency and timing in GF among tree species. We compared the flowering peaks between high- and low-frequency flowering trees based on the phenology data during 1993-2011. As expected, the flowering peak of high-frequency flowering species preceded that of low-frequency species. The soil water sources of the dipterocarp trees were assessed using oxygen stable isotope composition (δ18O) with snap- and sequence-shot methods. Although both an unclear vertical profile of soil water δ18O and the short sampling term made it difficult to estimate the water uptake depth using either method, δ18O of dipterocarp trees is likely influenced by flowering frequency. However, an accurate estimation of vertical pattern of soil water use by tropical trees will be required to fully test this hypothesis., This proceeding is a compilation of findings and progress activities of research collaboration between the Forest Department Sarawak (FDS) and the Japan Research Consortium for Tropical Forests in Sarawak (JRCTS). To highlight the research findings, An International Symposium entitled "Frontier in Tropical Forest Research: Progress in Joint Projects between the Forest Department Sarawak and the Japan Research Consortium for Tropical Forests in Sarawak" was ii held in Kuching, Sarawak on 21-22 September 2015.

Established mangrove forests along the coastal area of the Arabian Peninsula and African side of the Red Sea are uniquely different from mangrove forests in other parts of the world because of their low biodiversity and harsh habitat of arid and highly saline conditions. Therefore mangrove forests in this area appear in patchy and scattered patterns at mouths of wadi or in sheltered lagoons with rare and irregular flooding. Most of them are pure forests of Avicennia marina, occasionally mixed with Rhizophora mucronata in the southern part of the Red Sea. In this study, we analyze the forest structure of A. marina and discuss the regeneration strategy and the forest dynamics of this unique mangrove species. Three experimental plots of 1000 to 2000 trees/ha were selected from north to south along the Red Sea coast. The highest tree size (6.8m) suggested severe effects of the high salinity of the Red Sea (3.2 to 4.9%) on tree growth. Dense mantle vegetation had developed at the forest edge facing the open sea to protect the forest interior against strong waves and wind. Tree growth was also prevented by severe drought on the landside edge of the forest. All the forests had a dense seedling bank throughout the forest floor, with a very high rate of turnover and regeneration, which seldom occurred in other forests.

2章 個体・環境の測定 3, 光合成活動に影響を与える要因の一つである葉の蒸散特性の評価法として，ガスチャンバー（同化箱）法による解析と重量法による解析がある．これらの解析は蒸散に関する種特性を評価する上で有効である．, Gas chamber methods and gravimetric methods of dehydration from leaves can provide evaluation of transpiration properties, which are the factors affecting photosynthesis. These analyses would be suitable to evaluate inter-specific differences in transpiration properties in plant species.