巻号一覧
50 巻 (1994)
- 3-4 号 p. 177-
- 2 号 p. 97-
- 1 号 p. 1-
50 巻, 2 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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毛 光伶, 蔵田 憲次1994 年 50 巻 2 号 p. 97-100
発行日: 1994/09/10
公開日: 2010/02/25
ジャーナル フリーEffect of rowcovers made of non-woven fabrics on wind profiles above vegetation model was studied in a wind tunnel. Three kinds of covering materials were placed directly on the wooden cylinder vegetation model. Two wind profiles of 0.46ms-1 and 0.92ms-1 at the height 45cm were created and parameters related to turbulent diffusion of momentum were calculated. Above the cover made of split fibers, turbulent diffusion was promoted, while that was suppressed above two kinds of spunbonded fibers compared to the case in which canopy was not covered. However, the change of the turbulent diffusion resistance by the covers was restricted to the range of 75-175%.抄録全体を表示PDF形式でダウンロード (483K) -
近藤 純正, 大岡 浩明1994 年 50 巻 2 号 p. 101-107
発行日: 1994/09/10
公開日: 2010/02/25
ジャーナル フリーObservations of evaporation from bare soils (sand and loam) were carried out for a long term by using lysimeters. The decrease in evaporation from sand is larger than that from loam in drying processes after rainfall. The multilayer soil model (Kondo, 1993; 1994b; Kondo and Saigusa, 1994) simulates well the present observation of evaporation. Total amount of observed evaporation for a period of 416 days is 583mm, and that of calculated evaporation is 616mm. In the model the surface heat budget and diffusion of water vapor in the soil pores are taken into consideration.抄録全体を表示PDF形式でダウンロード (807K) -
木村 和義, 有吉 美智代1994 年 50 巻 2 号 p. 109-113
発行日: 1994/09/10
公開日: 2010/02/25
ジャーナル フリー植物体内成分に対する雨濡れの影響を明らかにするため, 降雨日を想定した弱い日射条件 (61W/m2) で, 5日間の降雨処理によるインゲンマメ植物の生体重, 乾物重および可溶性糖, デンプン, 窒素含量の変化について検討した。
1) 降雨処理により植物体の乾物重, 可溶性糖, デンプン, 窒素含量は減少した。降雨処理を受けた植物の乾物重は無処理植物の78%, 可溶性糖含量は72%, デンプン含量は57%, 窒素含量は83%の値に減少した。乾物重, 可溶性糖, デンプン含量の低下は地上部 (葉, 茎) において根よりも顕著であった。窒素含量の低下の程度は少ないが, 根が葉, 茎よりも減少した。
2) 5日間の降雨処理期間中の可溶性糖, デンプン, 窒素含量の増加率は無処理植物よりも少なくなったが, 特に茎のデンプン含量は減少が著しく, 降雨処理開始時の約1/2の値になった。
3) 本実験の結果から, 植物体の雨濡れは糖類の含量に著しく影響を与え, 特に葉, 茎のデンプン含量の低下をもたらすことが明らかになった。
本研究の経費の一部は文部省科学研究費補助金 (一般研究C 課題番号63560249) によった。抄録全体を表示PDF形式でダウンロード (597K) -
川方 俊和, 矢島 正晴1994 年 50 巻 2 号 p. 115-120
発行日: 1994/09/10
公開日: 2010/02/25
ジャーナル フリーThis study was conducted to develop a simple model of leaf dry weight and top dry weight of rice (Oryza sativa L.) plants. Rice variety “Nipponbare” was sown five times at one-month interval from April through August, 1992, and was transplanted in a paddy field at National Institute of Agro-Environmental Sciences (NIAES), Tsukuba, Japan about three weeks after the sowing. Plants samples were taken every two weeks to measure biomass and leaf area. Photon flux densities upon and below the rice canopies were measured to calculate light interception by the rice plants. Incident shortwave radiation and air temperature were recorded at the NIAES weather monitoring station. The data on biomass, light interception and the weather variables were used to develop the model. In the model, total leaf dry weight was described by a combination of exponential and linear functions of accumulated air temperature, and the dead leaf dry weight was expressed as a linear function of accumulated air temperature. Leaf dry weight was defined as the difference between the total and dead leaf dry weight, and was used to calculate light interception. Top dry weight was estimated as the product of the intercepted shortwave radiation and the radiation-use-efficiency (RUE). The model fitted rather well to the observation of the leaf dry weight, but it overestimated top dry weight with a constant RUE throughout the growing season. To correct the overestimation, the total leaf dry weight was further divided into active leaf dry weight and the senescent leaf dry weight, among which only the active leaf dry weight was used to calculate the light interception. The leaf senescence was assumed to be a function of accumulated air temperature. The revised model gave a good fit with regard to the top dry weight, and may be useful to represent crop production.抄録全体を表示PDF形式でダウンロード (834K) -
細野 達夫, 野内 勇1994 年 50 巻 2 号 p. 121-127
発行日: 1994/09/10
公開日: 2010/02/25
ジャーナル フリーEight species of crop were exposed to simulated acid rain (SO42-: NO3-: Cl-=2:1:2, equivalent ratio) at pH 5.6 (control), 3.0, 2.7 and 2.5 throughout their entire growing periods. Plant were subjected to acid rain treatment three times a week, for one hour with 7-13mm of precipitation at a time. Simulated acid rain at pH 3.0 or below produced foliar visible injury on leaves of all the tested plants in this study. Injury degree of the foliar visible symptoms was varied among plant species. In addition, injury degrees were different among leaf positions: injury was severer in lower lesf position, particularly cotyledons and primary leaves, than upper one. In many cases in this study, foliar visible injury was severer at the early stages of growth than the later stages. Dry weight of rice plants exposed to simulated acid rain at pH below 3.0 was reduced compared with pH 5.6 at early stage of growth. At the middle to late growth stage, however, acid rain treatment did not affect the growth of rice plants. The relationship between pH of simulated acid rain and yield loss in each crop suggested that acid rain at pH 3.0 or less acidity would not cause yield reduction at any crop. In the lower pH range less than 3.0, yield loss acidity in simulated acid rain varied among plant species. The yield of rice was not reduced even at pH 2.5.抄録全体を表示PDF形式でダウンロード (925K) -
観測と理解日本農業気象学会局地気象研究部会1994 年 50 巻 2 号 p. 129-133
発行日: 1994/09/10
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (776K) -
後藤 英司1994 年 50 巻 2 号 p. 135-139
発行日: 1994/09/10
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (674K) -
林 真紀夫1994 年 50 巻 2 号 p. 141-144
発行日: 1994/09/10
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (694K) -
清野 豁1994 年 50 巻 2 号 p. 145-148
発行日: 1994/09/10
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (659K) -
耕地気象改善研究部会1994 年 50 巻 2 号 p. 149-151
発行日: 1994/09/10
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (436K)
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