巻号一覧
70 巻 (2014)
- 4 号 p. 171-
- 3 号 p. 133-
- 2 号 p. 73-
- 1 号 p. 1-
70 巻, 1 号
選択された号の論文の5件中1～5を表示しています
- |<
- <
- 1
- >
- >|
Full Papers
-
Hirakazu SEKI, Shiro KIYOSE, Shoko SAKIDA2014 年 70 巻 1 号 p. 1-11
発行日: 2014年
公開日: 2014/03/12
ジャーナル フリーWe performed experiments using a small, laboratory-scale apparatus for validating a system of recovery, accumulation, and utilization of the heat generated by bamboo chip biodegradation. This system is based on the effective use of biomass resources and is needed to support industrial progress in low population regions such as Noto, Ishikawa Prefecture, Japan. This paper is the first attempt at quantifying the use of heat to warm an aquaculture pond. Although conduction is the main heat transfer mechanism in the bamboo chip pile, physical models of heat conduction are mathematically complex. Therefore, we considered the heat conduction effects concentrated around the heat extraction pipe embedded in the bamboo chip pile, and obtained relatively simple analytical solutions for the temperature in the bamboo chip pile, water reservoir for heat accumulation, and conceptual fishpond (i.e., a heat utilization subsystem). Based on the experiment's results and the simplified model, we discussed the validity of the comprehensible heat transfer model and the feasibility of the proposed system.抄録全体を表示PDF形式でダウンロード (873K) -
Masashi OKADA, Toshichika IIZUMI, Masayuki YOKOZAWA2014 年 70 巻 1 号 p. 13-23
発行日: 2014年
公開日: 2014/03/12
ジャーナル フリーThis study is a global assessment of the performance of two empirical models for estimating daily global solar radiation (SR) in the present-day climate, as well as the applicability of these models for near-future climates. One empirical model is used to estimate SR from a diurnal temperature range (DTR) and is called the DTR-SR model, while the other is used to estimate SR from relative humidity (RH) and is called the RH-SR model. Using data from the reanalysis and atmosphere-ocean coupled global climate model (GCM) known as MIROC4, we found that the DTR-SR model operates more accurately over land than the RH-SR model, though the RH-SR model outperformed the DTR-SR model over the ocean. Based on an assessment using data from the decadal prediction performed by the GCM, the DTR-SR model could be applied to estimate GCM-simulated SR in altered climates until the year 2035 considered in this study, given the comparatively limited performance of the model during the winter and in arid and semi-arid regions. This suggests that the DTR-SR model is likely useful for data imputation if GCM-simulated SR data are unavailable.抄録全体を表示PDF形式でダウンロード (1510K) -
Akemi TANAKA, Tomonori SATO, Manabu NEMOTO, Yasuhiro YAMANAKA2014 年 70 巻 1 号 p. 25-40
発行日: 2014年
公開日: 2014/03/12
ジャーナル フリーIn Hokkaido, in northern Japan, rice yields are frequently affected by cool summers in the present climate. Recently, several studies have noted the possibility that cool summer damage may not be reduced even with global warming due to earlier rice phenology. We examined the changes in the range of rice sterility associated with rising temperatures focusing on inter-annual variation in temperature. By raising daily mean and daily maximum temperatures uniformly, we calculated the sterility rate of the Kirara397 variety locally planted in Hokkaido. Generally, long-term mean rice sterility decreases with rising temperatures. However, in each year and with each transplanting date, rice sterility remains identical to the present or even worsens in some cases. We called those cases “accelerated cool summer damage” (ACSD). In the cases of rising temperature, the growth rate is accelerated, and the period of vulnerability to low temperatures become earlier. When the temperature during the earlier period of vulnerability is equal to or less than that during the original period of vulnerability in the present, ACSD occurs. Future rice sterility that induces cool summer damage may remain even if the temperatures rise associated with global warming, since the increase in temperature during the period of vulnerability is smaller than the range of inter-annual variation in temperature. We also found that there is a possibility that extremely high rice sterility is increased in a warmer climate if the range of inter-annual variation in temperature expands. This finding suggests that rice sterility may be increased by the inter-annual variation in temperature, even if the long-term mean sterility decreases as the temperature rises.抄録全体を表示PDF形式でダウンロード (1622K) -
Makoto OOBA, Kiichiro HAYASHI, Takashi MACHIMURA, Takanori MATSUI2014 年 70 巻 1 号 p. 41-54
発行日: 2014年
公開日: 2014/03/12
ジャーナル フリーA quantitative assessment of carbon circulation was carried out between forest ecosystems and human society on a city scale from multiple aspects. A biogeochemical forest model that had been developed for the evaluation of ecosystem services (carbon sequestration, nitrogen leaching, water runoff, and wood biomass provisioning) was used for simulation under several forest management scenarios. From the perspective of trade-offs between the practice and cost of management, the management and production costs of each scenario were calculated using a forestry cost model. Management scenarios were prepared with a business-as-usual (BAU) approach, management plans proposed by local forest administrators, and the authors that promote management and forest conversion into natural (secondary) forest. From the results, carbon sequestration under active forest management was two or four times larger than that under the BAU scenario in 2100. Volumetric cost of the wood biomass production depended on the schedule of forest management (thinning and rotation length).
For an understanding of these results about carbon circulation from the models, we also investigated carbon demands from human society, such as wood consumption for construction and paper products. The production of wood was somewhat lower than the demand from the wood industry. However, promoting production according to the scenarios applied in the study was effective for meeting supply and demand. The carbon sequestration by the forest in Toyota City was one twenty-fifth of the carbon emissions from energy consumption in the city.
Finally, increased production of wood biomass that considers ecological and economic effects can be sufficient to satisfy the demand for wood biomass for the activities of human society.抄録全体を表示PDF形式でダウンロード (1091K) -
Naru TAKAYAMA, Koji KAWAMURA, Haruhiko YAMAMOTO, Shohei NOBORI, Yosuke ...2014 年 70 巻 1 号 p. 55-67
発行日: 2014年
公開日: 2014/03/12
[早期公開] 公開日: 2014/01/31ジャーナル フリーIn this study, wall greening with vines was constructed using a simple net on a south wall, and the water consumption of the plants was evaluated. A model to estimate the water requirement for wall greening was proposed in which weather conditions and plant growth were considered as explanatory variables. From August 20, 2011 to October 2, 2011, the mean daily water consumption was 18.4 mm, the estimated total water consumption was 1.8 m3 and the mean leaf area per unit of ground (LAIg) was 11.0. We defined the ratio of water consumption to the maximum value as the standard ratio of water consumption, and estimated the daily standard water consumption rate with our model that uses several climatological factors and LAIg as explanatory variables. The mean absolute error for the estimation was 6.1 %, suggesting that the water consumption of the wall greening could be evaluated quantitatively through investigation of the water balance of plants.抄録全体を表示PDF形式でダウンロード (1218K)
- |<
- <
- 1
- >
- >|