巻号一覧
66 巻 (2010)
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66 巻, 4 号
選択された号の論文の10件中1～10を表示しています
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研究論文（英文）
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中野 聡史, 小南 靖弘, 大野 智史, 横山 宏太郎2010 年 66 巻 4 号 p. 207-216
発行日: 2010/03/10
公開日: 2011/04/04
ジャーナル フリー昼間よりも夜間のフェーン風の遭遇が水稲の白穂被害を大きくすることが知られている。しかし他の作物においては夜間のフェーン風の影響を調査した例が見られない。そこで本研究では，夜間のフェーン風がダイズの茎内流量と気孔コンダクタンスに及ぼす影響を調べた。茎内流量は蒸散量とほぼ一致する量であると考えられており，茎熱収支法を用いて測定した。茎内流量センサーのゲージ係数はフェーンが発生する前後の日の値から決定した。気孔コンダクタンスは茎内流量と気象データから計算した。フェーン発生時の夜間はフェーンが発生していない夜間よりも茎内流量が大きく，平均茎内流量は2007年で4.3 g h-1，2008年で4.0 g h-1となった。また夜間の積算茎内流量は昼間の値に対して2007年は10.5％，2008年は7.0％となった。ただ両年における夜間の茎内流量の増加の仕方は異なっており，2007年は大気飽差が0.7 kPa以上になると大気飽差の増加にしたがって直線的に増加したが，2008年では大気飽差が0.8 kPaを超えると急激に増加した。このような茎内流量の大気飽差に対する反応の違いは気孔コンダクタンスの違いによるものと推察され，気孔コンダクタンスの違いは2007年と2008年の土壌水分の違いに起因すると考えられた。抄録全体を表示PDF形式でダウンロード (956K) -
松田 怜, 鈴木 克己, 中野 有加, 佐々木 英和, 高市 益行2010 年 66 巻 4 号 p. 217-226
発行日: 2010/03/10
公開日: 2011/04/04
[早期公開] 公開日: 2010/09/30ジャーナル フリーCO2施用しない条件下で検討された，トマトのロックウール養液栽培における作物吸水量にもとづいた養分量管理の日施用法が，作物の成育や養分要求量が変化するCO2施用条件下にも適用できるか否かについて，慣行の培養液電気伝導度（EC）にもとづくかけ流し式管理と比較することで検証した。また量管理の日施用には，新規に開発した量管理コントローラ親機および子機のプロトタイプによる自動量管理システムを用いた。量管理処理区は，3日間の平均吸水量あたりの養分施用量を，CO2施用しない条件下で最適とされる養分施用量の0.5倍（S区），1.0倍（M区），および1.5倍（L区）の3処理区とした。栽培試験は高軒高温室において2009年10月から2010年2月にかけて行った。栽培期間中の積算総果実収量は慣行のEC管理区において最も高く，次いでL区，M区，S区の順に高かった。他方，積算正常果収量はEC管理区，L区，M区との間に有意な差はみられず，S区においてのみ有意に低かった。量管理処理区における果実乾物率や果実糖度は，EC管理区におけるそれらと同程度かあるいは高かった。量管理処理区において栽培期間中に培養液として使用した無機成分量はEC管理区よりも少なく，S区，M区，およびL区においてそれぞれEC管理区の10，24，および42％であった。量管理3処理区における無機成分利用効率（無機成分使用量あたりの積算正常果収量）はいずれもEC管理区におけるそれより高かった。以上より，養分量管理の日施用法はCO2施用条件下においても収量や収穫物品質を低下させることなく養分使用量を削減しうることがわかった。本研究の条件下では，正常果収量はL区の方がM区よりも幾分高かったことから，正常果収量をわずかでも高めたい場合にはL区が，また無機成分利用効率を高めたい場合にはM区が，それぞれ適しているものと判断された。抄録全体を表示PDF形式でダウンロード (793K) -
Tadaaki URANO, Mitsuru HIROTA, Byambakhuu ISHGALDAN, Sheng-Gong LI, Ju ...2010 年 66 巻 4 号 p. 227-236
発行日: 2010/03/10
公開日: 2011/04/04
[早期公開] 公開日: 2010/11/02ジャーナル フリーWe examined the effects of grazing on aboveground biomass (AGB), vegetation constitution, and gross primary productivity (GPP) at midday in midsummer on a Mongolian steppe with mixed vegetation consisting of C3 and C4 plants. A grazed area (GA) and a nongrazed area (NGA) created by an exclosure were established in 2002 on land with a history of conventional grazing management. AGB of the mixed C3-C4 vegetation was determined in the GA and NGA from 2003 to 2006. Nongrazing resulted in increased AGB and a decreased ratio of C4 AGB to total AGB. In 2003 and 2006 a dynamic closed-chamber method was used to measure midday GPP; there was no significant difference between the GA and NGA in either year. Partitioning analysis of midday GPP to C3 and C4 photosynthesis indicated that exclosure exerted little influence on the midday GPP in midsummer, because the enhancement of GPP by increased AGB was offset by the reduced AGB of C4 plants.抄録全体を表示PDF形式でダウンロード (767K)
研究論文
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武田 知己, 小熊 宏之, 石濱 史子, 竹中 明夫2010 年 66 巻 4 号 p. 237-244
発行日: 2010/03/10
公開日: 2011/04/04
[早期公開] 公開日: 2010/11/02ジャーナル フリーInformation on the ground surface can now be acquired easily and highly accurately using digital aerial photographs. A digital canopy model (DCM), which is calculated by subtracting a digital terrain model (DTM) from a digital surface model (DSM) of the vegetation, provides useful information for studies of wild animal habitats and plant species distributions. However, DCMs have been used mainly for forests, and their validity for herbaceous plants requires further verification. In this study, we used the ADS40 airborne digital sensor to clarify the relationship between a DCM and the height of herbaceous species. Our study area was the Watarase wetland in the northern Kanto Plain, central Japan. Suitable habitats for the many rare plants found in this wetland are maintained by controlled burning in early spring. We acquired three DSMs: just after the controlled burn in April 2006; in August 2006, when the vegetation height peaked; and in April 2007, also just after the controlled burn. We calculated the DCM based on the difference between the August DSM and a DTM developed by using the minimum height values from the two April DSMs. We also performed a field survey during the August DSM acquisition, during which we measured the height of the uppermost leaves with a measuring pole at 16 measurement points and estimated the vegetation structure from photosynthetic photon flux density (PPFD) profiles measured with quantum sensors at each point. The calculated DCM height correlated very well to the height of the uppermost leaves (r2 = 0.96), although it was about 100 cm lower. In contrast, the DCM and the height of maximum intercepted PPFD were highly correlated (r2 = 0.97) and showed a 1:1 relationship.抄録全体を表示PDF形式でダウンロード (1268K) -
黒瀬 義孝2010 年 66 巻 4 号 p. 245-253
発行日: 2010/03/10
公開日: 2011/04/04
ジャーナル フリーUsing the air infiltration characteristics of a porous cup we developed a prototype measuring device that determines the degree of dryness of the soil (simple soil moisture measuring system). This simple soil moisture measuring system consists of a porous cup, a transparent polyvinyl-chloride pipe, and a silicon stopper. When the soil is drier than the air entry value of the porous cup, air enters into the polyvinyl-chloride pipe, which was made airtight by filling up water, via the porous cup. This air is pulled back through the negative pressure inside the polyvinyl-chloride pipe, and the water level inside the polyvinyl-chloride pipe drops. The drier the soil the more the water level inside the polyvinyl-chloride pipe drops. The simple soil moisture measuring system determines the degree of the dryness of the soil by using the drop of the water level inside the polyvinyl-chloride pipe as a marker.抄録全体を表示PDF形式でダウンロード (832K) -
脇山 恭行, 大原 源二, 丸山 篤志2010 年 66 巻 4 号 p. 255-267
発行日: 2010/03/10
公開日: 2011/04/04
ジャーナル フリーData were analyzed to develop a model for predicting the incidence of immature rice kernels with white portions of the Hinohikari cultivar. The coefficient of determination (r2) between the incidence of white-based rice kernels and mean air temperature for 20 days after heading was high. Therefore, fitting a curve between these two parameters is a viable means of developing a prediction model for the incidence of white-based rice kernels. Milky white rice kernels are caused by high temperatures that accelerate the respiration rate of the rice plant, a lack of solar radiation, over-dense rice grains per m2 and low leaf blade nitrogen content, as well as heat that induces some ripening damage. Using these determinants, the following evaluation indicator was proposed:
DMG = SR × α × RUE/Gr
where SR is solar radiation, α the absorptance of solar radiation by the community of rice plants, RUE the radiation use efficiency and Gr the number of rice grains per m2. RUE could be influenced by air temperature and leaf blade nitrogen content. The relationship between air temperature and RUE was investigated considering the leaf color, which represents the leaf blade nitrogen content of the Koshihikari cultivar. RUE decreased with increasing air temperature and a high leaf color kept RUE high. The equations of the relationship between RUE and air temperature, and the leaf color value, express the influence of high temperature and leaf color on dry matter production. DMG of Hinohikari was successfully calculated by the same equation with an additional parameter. DMGHN for Hinohikari was plotted for the incidence of milky white rice kernels. The coefficient of determination between milky white rice kernels and DMGHN was high (r2 = 0.65). The following model used to predict the incidence of milky white rice kernels was obtained:
IMWK = 52.3 exp(-599.9 × DMGHN)
where IMWK was the incidence of milky white rice kernels (%).抄録全体を表示PDF形式でダウンロード (1139K) -
朝倉 利員, 杉浦 裕義, 阪本 大輔, 杉浦 俊彦, 弦間 洋2010 年 66 巻 4 号 p. 269-277
発行日: 2010/03/10
公開日: 2011/04/04
ジャーナル フリーFull bloom dates of the ‘Someiyoshino’ flowering cherry (Prunus×yedoensis Matsum.) and hourly temperature data at 46 observatories across Japan were used to develop a universal model for predicting the phenology without site specific calibration. The prediction model consisted of three sub models for endodormancy and ecodormancy stages respectively, as well as their transient dormancy stage. The chill unit model of the endodormancy stage was expressed as a concave-low parabolic equation with a maximum chill unit value of 1.0 optimal temperature. In ecodormancy, the effective temperature curve for bud growth to accumulate the growing degree hours (GDH) was expressed as a sigmoid function at temperatures exceeding 0℃. Usually temperatures below 0℃ are excluded for GDH accumulation; however, in this model a positive constant was included assuming the promotive effects on bud growth under successively higher temperatures. Since the transition from endodormancy to ecodormancy should be a gradual response, the GDH was weighted by another sigmoid curve of growth competence which determined the growth ability of buds to forcing temperatures. The growth competence was zero during the initial stage of endodormacny and started gradually climbing before the end of endodormancy. The model parameters were evaluated by examining the deviation of accumulated GDH and RMSE between the observed and predicted dates. First, the model was fitted to different climate sites, Aomori and Fukuoka, and then tested at other sites nationwide. The selected model required an accumulated chill unit of 1450 for endodormancy completion with an effective temperature range from -6 to 14℃, and then the accumulated development of 6000 GDH to reach full bloom. The model, based on hourly temperature data only, succeeded in expressing the trends of full bloom dates for almost all sites except for southern Kyushu region, with the RMSE between observed and predicted dates of 2.33 days.抄録全体を表示PDF形式でダウンロード (3575K) -
清水 庸, 大政 謙次2010 年 66 巻 4 号 p. 279-288
発行日: 2010/03/10
公開日: 2011/04/04
ジャーナル フリーThe flowering of the Japanese apricot (Prunus mume Sieb. et Zucc.), which is representative of phenological events in winter, is widely observed in Japan. Shifts in the flowering date are related to climate change such as global warming and the urban heat island effect. In the present study, we analyzed trends in the flowering date of the Japanese apricot to clarify temporal and spatial variation from 1961 to 2007 using statistical methods. Phenological and meteorological data were recorded by the Japan Meteorological Agency at 34 meteorological stations in Japan. By linear regression analysis of the flowering date (expressed as the day of the year, DOY) against the year, mean trends of this parameter were shown to be significantly negative (i.e. advancing flowering) at 15 stations (44% of the total), with no significant positive trends. Comparison of the mean flowering dates in the 2000s with those in the four subintervals (the 1960s-1990s) indicated that the number of stations showing significant negative trends decreased from the 1960s to the 1990s. In a few phenological stations, the flowering date was delayed. The first principal component of the trends accounted for 55% of the variation in the flowering date for the period 1961 to 2007 at 34 stations and reflected chronological progression in the flowering. In particular, a recent trend since the mid-1990s contributed to advancing trends during the period 1961-2007. From the mid-1980s, the flowering date was delayed at the Owase station and several stations in south-eastern Japan, located in warm areas. Conversely, a few stations in cold regions indicated that recent flowering dates were earlier than those in the 1970s and 1980s, in addition to the trends shown by the first principal component.抄録全体を表示PDF形式でダウンロード (1431K) -
斎藤 琢, 玉川 一郎, 村岡 裕由, 小泉 博2010 年 66 巻 4 号 p. 289-298
発行日: 2010/03/10
公開日: 2011/04/04
[早期公開] 公開日: 2010/09/30ジャーナル フリーThis study evaluated heat storage flux or released flux due to biotic activity (SC) in forests. First, as a case study, we investigated diurnal pattern of SC over an evergreen coniferous forest via a three-year continuous eddy-covariance CO2 flux measurement. We clarified that (1) in some case, SC reached over 15% of total heat storage flux during the snow-free period (May-October), (2) SC was 4.3 W m-2 on average and reached 4.9-7.0% of average sensible and latent heat fluxes during the snow-free period. Second, we estimated SC by using net ecosystem exchange over several forest ecosystems as reported by previous studies. During the snow-free period over several forest ecosystems, the maximum Sc and daily amplitude exceed 3-12 and 4-17 W m-2 respectively. Those values were comparable to those of the latent heat storage flux in the air layer from the ground surface to the level of eddy-covariance measurement over several forest ecosystems as shown by previous reports. Our findings suggest that SC cannot be always ignored. We would need to examine whether SC can be ignored based on the circumstances of the targeted research.抄録全体を表示PDF形式でダウンロード (823K)
短 報
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宮沢 佳恵, 岡田 益己2010 年 66 巻 4 号 p. 299-304
発行日: 2010/03/10
公開日: 2011/04/04
ジャーナル フリーThe authors investigated the effects of CO2 concentration and temperature on the eating quality of komatsuna (Brassica rapa var. peruviridis). The komatsuna was grown in two temperature-gradient chambers at three temperature levels averaging 18.9, 21.9, and 23.0°C. One of the chambers was used to produce an elevated ambient atmospheric CO2 concentration of 200 ppm. Among the six sensory quality factors evaluated by a ten-member panel, the sweetness rating and overall rating were significantly lower in samples grown under elevated CO2 compared to those grown under ambient CO2, regardless of the temperature regime. It is possible that the taste and nutritional quality of leafy vegetables could decline in future CO2 concentrations.抄録全体を表示PDF形式でダウンロード (796K)
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