Filters








33 Hits in 1.7 sec

Uptake of O3 by various street trees

Yasumi FUJINUMA, Akio FURUKAWA, Tsumugu TOTSUKA, Tadayoshi TAZAKI
1987 Environment Control in Biology  
Potted eleven street tree species (Aucuba japonica, Cinnamomum camphora, Daphniphyllum macropodum, Ginkgo biloba, Hedera rhombea, Ligustrum japonicum, Pasania edulis, Prunus yedoensis, Quercus acutissima, Rhododendron oomurasaki, Zelkova serrata) were treated with various concentrations of O3 to investigate the heritable differences in the capacity of O3 uptake. The rates of net photosynthesis and transpiration, and stomatal density were determined for every tree species. Some species showed a
more » ... inear relationship between O3 concentration and the uptake rate of O3, while other species did not. The analysis using a gas phase diffusive conductance indicated that the nonlineality was assumed to be resulted from the stomatal closure. Concerning those nine tree species which showed the linear increase in O3 uptake rate with O3 concentration, the rate of O3 uptake was ranked as follows: P. yedoensis=H. rhombea>Z. serrata=Q. acutissima>C. camphora=D. macropodum-G. biloba>A. japonica=R. oomurasaki. Those tree species with higher uptake rates of O3 were not characterized with higher stomatal frequency but with higher gas phase conductance for water vapor. This result suggested that the heritable differences in the rates of O3 uptake are determined by the interspecific differences in stomatal conductances.
doi:10.2525/ecb1963.25.31 fatcat:4mjwdervcjdwhmxux2kvcrn25q

Effect of ozone on stomatal conductance in sunflower leaves: Age-dependent inhibition

Yasumi FUJINUMA, Akio FURUKAWA, Ichiro AIGA
1988 Environment Control in Biology  
The effects of 03 on visible injury and stomatal conductance for water vapor transfer were determined during the leaf development of sunflower plant (Helianthus annuus L . cv. Russian Mammoth). The stomatal frequency and conductance were also measured during the leaf development. The foliar necrosis induced by the exposure to O3 was influenced by the leaf age. With increasing leaf age , the foliar necrosis increased from young to mature leaves, then decreased in senescent leaves. The effect on
more » ... tomatal conductance was also influenced. The inhibition of stomatal conductance on the pretreatment value basis decreased from young to senescent leaves . The degree of foliar necrosis had no linear relationship to the calculated uptake rate of 03 suggesting that the agedependent foliar sensitivity to 03 could not be determined by the amount of O3 incorporated into leaves but by the detoxicating capacity of absorbed O3 in the leaf.
doi:10.2525/ecb1963.26.83 fatcat:fnngh3jynjdmtapyoptxvyjo6y

Carbon dioxide exchange of a larch forest after a typhoon disturbance

Tomohito Sano, Takashi Hirano, Naishen Liang, Ryuichi Hirata, Yasumi Fujinuma
2010 Forest Ecology and Management  
A typhoon event catastrophically destroyed a 45-year-old Japanese larch plantation in southern Hokkaido, northern Japan in September 2004, and about 90% of trees were blown down. Vegetation was measured to investigate its regeneration process and CO 2 flux, or net ecosystem production (NEP), was measured in 2006-2008 using an automated chamber system to investigate the effects of typhoon disturbance on the ecosystem carbon balance. Annual maximum aboveground biomass (AGB) increased from 2.7 Mg
more » ... a -1 in 2006 to 4.0 Mg ha -1 in 2007, whereas no change occurred in annual maximum leaf area index (LAI), which was 3.7 m 2 m -2 in 2006 and 3.9 m 2 m -2 in 2007. Red raspberry (Rubus idaeus) had become dominant within 2 years after the typhoon disturbance, and came to account for about 60% and 50% of AGB and LAI, respectively. In comparison with CO 2 fluxes measured by the eddy covariance technique in 2001-2003, for 4.5 months during the growing season, the sum of gross primary production (GPP) decreased on average by 739 gC m -2 (64%) after the disturbance, whereas ecosystem respiration (RE) decreased by 501 gC m -2 (51%). As a result, NEP decreased from 159 ± 57 gC m -2 to -80 ± 30 gC m -2 , which shows that the ecosystem shifted from a carbon sink to a source. Seasonal variation in RE was strongly correlated to soil temperature. The interannual variation in the seasonal trend of RE was small. Light-saturated GPP (P max ) decreased from 30-45 μmol m -2 s -1 to 8-12 μmol m -2 s -1 during the summer season through the disturbance because of large reduction in LAI.
doi:10.1016/j.foreco.2010.09.026 fatcat:knb56ajex5dk5b7rlecjyoy5ia

The behavior of metallic components in the forest

Kunito HIRAJIMA, Motohiro HAMAYA, Takuya TOBISAWA, Tatsuya FUKAZAWA, Harukuni TACHIBANA, Karibu FUKUZAWA, Hideaki SHIBATA, Mutsu NOMURA, Kentarou TAKAGI, Yasumi FUJINUMA
2005 Proceedings of the Symposium on Global Environment  
doi:10.2208/proge.13.317 fatcat:qnymbs6wwbaldp4ag7y5q2kyye

Effects of low concentrations of Ozone (O3) on the growth of several woody plants

Hideyuki Shimizu, Yasumi Fujinuma, Kenzo Kubota, Tsumugu Totsuka, Kenji Omasa
1993 Journal of Agricultural Meteorology  
Fujinuma,K. Kubota, T. cedar without any visible damages (Table 1 ).  ... 
doi:10.2480/agrmet.48.723 fatcat:zihtuyqu3rb2zgjxz4eunzjx7y

A COMPARATIVE ANALYSIS OF THE UNIT ENERGY CONSUMPTION IN THE COMMERCIAL SECTOR

Yujiro HIRANO, Yutaka TONOOKA, Toshiharu IKAGA, Yukihiro KIKEGAWA, Yasumi FUJINUMA, Yoshiyuki SHIMODA
2008 Journal of Environmental Engineering (Transactions of AIJ)  
FUJINUMA and Yoshiyuki SHIMODA This paper describes the results of a literature survey and comparative analysis of unit energy consumption data in the commercial sector.  ...  COMPARATIVE ANALYSIS OF THE UNIT ENERGY CONSUMPTION IN THE COMMERCIAL SECTOR �� ���*, �� �**, ��� ��***, �����****, �� ��*****, �� ��****** Yujiro HIRANO, Yutaka TONOOKA, Toshiharu IKAGA, Yukihiro KIKEGAWA, Yasumi  ... 
doi:10.3130/aije.73.1331 fatcat:ztqv7kcrtbdhxmulg3n6amddiu

Ground-based millimeter-wave observations of ozone in the upper stratosphere and mesosphere over Tsukuba

Tomoo Nagahama, Hideaki Nakane, Yasumi Fujinuma, Mariko Ninomiya, Hideo Ogawa, Yasuo Fukui
1999 Earth, Planets and Space  
We present ground-based millimeter-wave observations of the upper stratospheric and mesospheric ozone, conducted at the National Institute for Environmental Studies (NIES) in Tsukuba, Japan (36 • N, 140 • E). The measurements were started in October 1995. The millimeter-wave radiometer used for the present study is equipped with the superconductor-insulator-superconductor (SIS) mixer receiver and the acousto-optical spectrometer (AOS). Vertical profiles of ozone mixing ratio from 20 to 80 km
more » ... e retrieved from the observed ozone spectra for 23 months from October 1996 to August 1998 by using the weighted-damped least squares algorithm adopted for differential emission. Vertical resolution is estimated to be 14 km from the averaging kernels. The total random error on the retrieval is estimated to range from 3 to 13% in summer, and from 2 to 9% in winter, respectively, between 38 and 76 km in altitude. The ozone number density at 38 km with the radiometer which was convolved with the vertical resolution of the lidar agrees well with that of the lidar within a systematic difference of 1%, indicating that the millimeter-wave data at 38 km are validated by the lidar measurements. Annual and semi-annual variations are clearly seen at 50 and 76 km, respectively, in the time series of the ozone mixing ratio observed during 23 months. The annual variation at 50 km is consistent with that in the climatological models. The semi-annual variation at 76 km observed in this work is similar to that of the Solar Mesospheric Explorer (SME) data, except that the ozone mixing ratio in spring measured with SME is about 1.7 times larger than that in autumn while those with the radiometer are almost same.
doi:10.1186/bf03351602 fatcat:jsui23neg5cppbvkvyleirbxbu

Measurement of 3-D Structure of Japanese Larch (Larix kaempferi Sarg.) by Laser Scanner
レーザスキャナを用いたカラマツ群落の三次元構造の測定

Tomomi TAKEDA, Hiroyuki OGUMA, Yasumichi YONE, Yasumi FUJINUMA
2005 Journal of Agricultural Meteorology  
In this study, in order to measure the three-dimensional structure of forest, a new technique using a laser scanner was developed in a five-year-old Japanese larch community with a tree height of about / m grown at the experimental field of the National Institute for Environmental Studies. The Japanese larch community was divided into cubic cells, and plant area density (PAD) was calculated for each cubic cell from the gap fraction, which is the probability that a laser beam passes through a
more » ... ic cell. Leaf area density (LAD) was estimated from the di#erence between PAD measured in November ,**and wood area density (WAD) measured in March ,**.. Average plant inclination angle (APIA) and average leaf inclination angle (ALIA) were also calculated. In order to verify a measuring method with a laser scanner, a comparison with the vertical distribution of LAD measured by the stratified clipping method was conducted. Although PAD measured with the laser scanner overestimated LAD measured by the stratified clipping method by a factor of two (r , ῒ*.32), the relation of + : + was found by LAD measured with the laser scanner and measured by the stratified clipping method (r , ῒ*.3.). The vertical distribution of LAD had a peak from + m to , m, and was well in agreement with the vertical distribution measured by the stratified clipping method. The three-dimensional distribution of LAD showed not only vertical distribution but also horizontal heterogeneity of canopy. ALIA calculated as an average of canopy was /1./ degrees. In conclusion, the method with the laser scanner was able to measure the three-dimensional structure of forest.
doi:10.2480/agrmet.61.39 fatcat:avg6ukl3cvcuxedehw4qn6h37u

Monitoring of the Vegetation Index Distribution in the South and Southeast Asian Region with NOAA AVHRR Satellite Images

Suehiro Otoma, Yoshifumi Yasuoka, Tadakuni Miyazaki, Akira Shimizu, Yasumi Fujinuma
1997 Journal of Agricultural Meteorology  
Fujinuma 3.3. Geometric correction The data from the seven bands obtained from the radiometric correction described above were then geometrically corrected .  ... 
doi:10.2480/agrmet.52.563 fatcat:7kuufe5wpndoxhffrhnm6b7auq

Influence of Elevated Air Temperature on the Relationship between Photochemical Reflectance Index (PRI) and Photosynthetic Light Use Efficiency of Poplar Leaves

Tatsuro NAKAJI, Hiroyuki OGUMA, Yasumi FUJINUMA
2005 Journal of Agricultural Meteorology  
doi:10.2480/agrmet.989 fatcat:gn73gltmijfojcznqzjqrwv7g4

Performance of optical indirect methods to assess the change in leaf area index of a larch plantation through thinning

Tomohito SANO, Takashi HIRANO, Tomomi TAKEDA, Yasumi FUJINUMA
2012 Journal of Agricultural Meteorology  
Materials and Methods Study Site This study was conducted at the Tomakomai Flux Research Site (TFRS) (Fujinuma et al., 2001) in Tomakomai National Forest (42°44´N, 141°31´E; elevation 140 m), Hokkaido  ... 
doi:10.2480/agrmet.68.1.5 fatcat:kdn4fydeafh7xdvzjwwanf3nri

Ground-Based Millimeter-Wave Radiometer for Measuring the Stratospheric Ozone over Rikubetsu, Japan

Tomoo NAGAHAMA, Hideaki NAKANE, Yasumi FUJINUMA, Atsushi MORIHIRA, Akira MIZUNO, Hideo OGAWA, Yasuo FUKUI
2007 Journal of the Meteorological Society of Japan  
A millimeter-wave radiometer was installed at Rikubetsu, Japan (43.5 N, 143.8 E) in March 1999, to monitor the vertical distribution of ozone and temporal ozone variations in the stratosphere. Since November 1999, we have been monitoring vertical profiles of the ozone mixing ratio in the altitude range from 22 to 60 km, with measurements at 2-km altitude intervals. The systematic error was estimated to be 10%-15% positive above 28 km, and the total random error to be 5%-21%. Comparisons of the
more » ... ikubetsu radiometer data with ozone sondes at Sapporo, and HALOE show that the ozone-mixing-ratio data, between 22 and 32 km, agree within the calculated 10% systematic error. On ( 2007, Meteorological Society of Japan temporary ozone decreases of 37% and 15% at 22 and 30 km were found, respectively, when the potential vorticity at 550 K and 800 K increased. Suggesting that the ozone decrease may have been due to the arrival of a different airmass. During this event, the temporal variation of the ozone mixing ratio was clearly detected with small scatter, indicating that the Rikubetsu radiometer measurements have sufficient precision and time resolution to detect such short-term variations of stratospheric ozone.
doi:10.2151/jmsj.85.495 fatcat:hoticgbdrfaqjn6by5d7tl5hie

Comparisons of gap-filling methods for carbon flux dataset: A combination of a genetic algorithm and an artificial neural network

Makoto Ooba, Takashi Hirano, Jun-Ichi Mogami, Ryuichi Hirata, Yasumi Fujinuma
2006 Ecological Modelling  
Artificial neural network (ANN) Gap-filling Genetic algorithm (GA) Larch forest Net ecosystem exchange (NEE) a b s t r a c t In many cases of field measurements, missing data of net ecosystem CO 2 exchange (NEE) constitute a quarter to almost half of all data. Those omissions result from accidents of instruments, unfavorable weather, and quality-control screening. Accurate gap-filling methods are needed for interpolating these missing data. This study evaluated the performance of interpolation
more » ... ethods for gap-filling of NEE data: a conventional method with empirical equations of bioreaction whose parameters were estimated using nonlinear regression (NR) methods, an artificial neural network (ANN) method, and an automated ANN method (genetic neural network, GNN). In the GNN method, parameters of an ANN model, such as initial weight matrixes and input-data-selections, were determined automatically using a genetic algorithm (GA). A tested dataset was observed in a Japanese larch plantation in northern Japan for 5 months from May to September 2002. The available dataset was divided into two subsets to train and validate the models. Averaged coefficients of determination (r 2 ) of ANN models between observed and estimated values of NEE were almost identical to that of the NR method (r 2 = 0.86). The performance of the GNN method (r 2 = 0.88, averaged value) was somewhat better than those of the two methods. Using the GNN method, the mean daily NEE was estimated at −0.29 mol m −2 d −1 for the 5-month period using ANNs, thereby showing better performance. The mean daily NEE, which was reported previously, was compatible with that from the NR method (−0.23 mol m −2 d −1 ). From those results, it was concluded that the proposed GNN method offers better performance for gap-filling and high availability because of the obviated need for specialization of ecological or physiological mechanisms. (M. Ooba). depict the current and future global biospheric environments. International and interdisciplinary efforts (e.g., FLUXNET and regional observation networks) might achieve exact maps of terrestrial carbon cycles including some elucidations of a 0304-3800/$ -see front matter
doi:10.1016/j.ecolmodel.2006.06.006 fatcat:ktxqphgqyzbcjlz7e3grdqidgy

Direct Purification of Outflow from Rice Cultivation Fields
水田排水の直接的浄化の試み

Yasuhumi MORI, Taro TSUBOYA, Takuya NIIMURA, Yasumi FUJINUMA
1998 Transactions of The Japanese Society of Irrigation, Drainage and Reclamation Engineering  
Fig.1 試 験 水 田 Rice cultivation fields for experiment Taro TSUBOYA**, Takuya NIIMURA*** and Yasumi FUJINUMA* * National Institute for Environmental Studies (16-2 Onogawa, Tsukuba, Ibaraki 305-0053, JAPAN  ... 
doi:10.11408/jsidre1965.1998.197 fatcat:i3wpi7vicrdo7apk7tj2ebeg7i

Ammonia Emission from a Young Larch Ecosystem Afforested after Clear-Cutting of a Pristine Forest in Northernmost Japan

Kentaro Hayashi, Kentaro Takagi, Izumi Noguchi, Karibu Fukuzawa, Hiroyuki Takahashi, Tatsuya Fukazawa, Hideaki Shibata, Yasumi Fujinuma
2008 Water, Air and Soil Pollution  
The present study aimed to elucidate the atmosphere-forest exchange of ammoniacal nitrogen (NH X -N) at a young larch ecosystem. NH X -N exchanges were measured at a remote site in northernmost Japan where 4-year-old larches were growing after a pristine forest had been clear-cut and subsequent dense dwarf bamboo (Sasa) had been strip-cut. The site was a clean area for atmospheric ammonia with mean concentrations of 0.38 and 0.11 μg N m −3 in snowless and snow seasons, respectively. However,
more » ... re was a general net emission of NH X -N. The annual estimated emission of NH X -N of 4.8 kg N ha −1 year −1 exceeded the annual wet deposition of 2.4 kg N ha −1 year −1 , but the weekly exchange fluxes may have been underestimated by 28-60%. The main cause of the ammonia loss from the young larch ecosystem was probably enhanced nitrogen supply stimulated by the cutting of the pristine forest and Sasa, in particular, the Sasa.
doi:10.1007/s11270-008-9891-9 fatcat:goddo5oicneytl6x6sdm5f3i3m
« Previous Showing results 1 — 15 out of 33 results