農業気象
Online ISSN : 1881-0136
Print ISSN : 0021-8588
ISSN-L : 0021-8588
特集号: 農業気象
60 巻, 6 号
第6回大気汚染と地球環境変化に対する植物の反応に関する国際シンポジウム
選択された号の論文の32件中1~32を表示しています
序文
  • Kenji Omasa, Isamu Nouchi, Eiji Goto, Kazuo Oki, Yo Shimizu
    2005 年 60 巻 6 号 論文ID: Preface
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     The 6th International Symposium on Plant Responses to Air Pollution and Global Changes was held in Tbukuba Center for Institutes and EPOCHAL TSUKUBA, 'Isukuba, Japan, October 19-22, 2004. This symposium in Japan has been proposed by the late Alan R. Wellburn, who was in the past one of the major moderators of this symposia series. The aim of the symposium is to bring together scientists of various disciplines, who are actively involved in research on the impacts of gaseous air pollutants and global change on plant functioning and growth from molecular to ecosystem scales. The previous symposia were held in Oxford, UK, 1982 (1st), in Munich, Germany, l987 (2nd), in Blacksburg, USA, 1992 (3rd), in Egmond aan Zee, The Netherlands, 1997 (4th) and in Pulawy, Poland, 2001 (5th).
     This special issue is one of three issues (a volume published in Springer and special issues of Phyton and Journal of Agricultural Meteorology) and contains a selection of contributed papers to the symposium. The papers were peer reviewed under session or topic editors. The publication has been executed with a grant from the Commemorative Organization for the Japan World Exposition('70).
APGC特集号論文
  • Yasuhiro TAKO, Takashi TANI, Ryuji ARAI, Go HONDA, Osam KOMATSUBARA, M ...
    2005 年 60 巻 6 号 p. 1099-1104
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     “Closed Ecology Experiment Facilities”(CEEF) were constructed at the Institute for Environmental Sciences in Japan to conduct stable carbon isotope tracer experiments for improvement of prediction models on dynamics of radioactive carbon in the environment. A model closed ecosystem including two people, two goats and crops (150 m2), is to be established for four months yearly from 2005 to 2009 in the CEEF. In the experiment conducted under closed conditions in 2003, rice, soybean, peanut and safflower were cultivated sequentially in the closed “Plant Module”(PM) of the CEEF. Transplanting (or seeding) and harvest of each crop at regular intervals were maintained during 28 days, and flows of CO2, O2 and carbon to and from the crops were analyzed. Gas exchange rate and carbon balance of six female goats were determined in a gastight chamber during three or four days using an open-flow measurement system, Human habitation tests in the CEEF lasting five days were conducted under ventilated condition in 2003. Gas exchange of people was calculated using equations predicting gas exchange rate from energy consumption estimated from time records of activity, age and body weight, and respiration quotient (RQ = CO2/O2) measured during experiments conducted outside the CEEF. Total CO2 and O2 exchange for two goats and two men was estimated to be 62 and 71% of those of crops, respectively. It was deduced from the estimation that carbon balances of these three ecosystem components will be equivalent in the long-term. Water balance of crops was also measured or estimated for the 28-day cultivation period. Water balance of animals was also measured or estimated based on closed holding experiments. Water balance of human was measured during the five-day habitation study. The flows of water for the crops, animals and human in the CEEF system were estimated for the most part successfully, although small inconsistence exist.
  • Makoto WAITANABE, Tetsushi YONEKURA, Yukie HONDA, Masatoshi YOSHIDOME, ...
    2005 年 60 巻 6 号 p. 1105-1108
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     The effects of O3 and /or chronic mild water stress on photosynthetic characteristics and leaf antioxidative systems of Fagus crenata seedlings were investigated. The seedlings were exposed to charcoal-filtered air or 60 nmol mol-1 O3 for two growing seasons. In each gas treatment, the seedlings were received 250 ml (well-watered) or 175 ml (water-stressed) of water at 3-day intervals during the growth period. The O3 significantly reduced net photosynthetic rate, Rubisco concentration and chlorophyll concentration without stomatal closure, and significantly increased ascorbate concentration in the leaves of the seedlings. On the other hand, the water stress significantly reduced net photosynthetic rate and stomatal diffusive conductance to water vapor without significant reductions in the concentrations of Rubisco and chlorophyll, and significantly increased glutathione concentration in the leaves of the seedlings. Significant antagonistic effects of O3 and water stress were detected on net photosynthetic rate of the seedlings in September and October. In conclusion, because chronic mild water stress induces not only stomatal closure, but also increase of leaf glutathione concentration, the extent of the negative effects of O3 on net photosynthesis of Fagus crenata is less under the water-stressed condition than under the well-watered condition.
  • Kazuyuki KUCHITSU, Yasuhiro KADOTA, Takamitsu KURUSU
    2005 年 60 巻 6 号 p. 1109-1111
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Ion fluxes including Ca2+ and production of reactive oxygen species (ROS) are induced at the early step of defense signaling triggered by both biotic and abiotic (environmental) stresses. To reveal the molecular mechanisms and physiological roles of the plasma membrane Ca2+ influx, a family of putative voltage-gated Ca2+ permeable channels, the TPC1 family, were identified from various plant species. The rice gene, OsTPC1, rescued the Ca2+ uptake activity and growth rate of a yeast mutant defective in Ca2+ uptake. OsTPC1 overexpressing cells showed hypersensitivity to excess Ca2+ but higher growth rate under Ca2+ limitation, while growth of the transposon-insertional mutant (Ostpc1) cells was less sensitive to extracellular free Ca2+ concentration, suggesting that OsTPC1 has Ca2+ transport activity across the plasma membrane. Knockdown/knockout of the TPC1 family resulted in inhibition of [Ca2+]cyt rise in response to a pathogenic elicitor, as well as suppression of the elicitor-induced programmed cell death and defense-related gene expression. These results suggest that the TPC1 family is involved in elicitor-induced Ca2+ mobilization, and have crucial roles in stress-induced signal transduction pathways in plants.
  • Masazumi KAYAMA, Ali M. QUORESHI, Yoshinori KITAHASHI, Yasunori NAKAGA ...
    2005 年 60 巻 6 号 p. 1113-1115
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     The growth of two spruce species (Picea abies (L.) Karst., and Picea glehnii Masters) planted along roadsides is often reduced by salt stresses. To analyze the toxicity of deicing salts, we measured needle lifespan, and the concentration of chlorophyll, sodium, and chlorine of the two spruce species at damaged and healthy sites. In the needles of P. abies large amounts of sodium and chlorine were detected, especially in winter. Chlorophyll concentration in needles of P. abies decreased, and needle shedding accelerated. By contrast, in P. glehnii no difference was found in the concentration of sodium, chlorine, and chlorophyll, and in survivorship of needles between summer and winter. Therefore, we concluded that effect of salt spray was larger for the site of P. abies than that of P. glehnii.
  • Daisuke YASUTAKE, Masaharu KITANO, Kota HIDAKA, Wenjun HE, Tetsuo KOBA ...
    2005 年 60 巻 6 号 p. 1117-1120
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     A new method for evaluating rate of tanspirational water loss from the crop field was proposed and examined on the basis of rise in leaf temperature caused by application of abscisic acid (ABA) to plants. ABA is a plant honnone which induces stomatal closure and depression of transpiration without any change in turgidity and spectrum characteristics of leaves. By measuring the rise in leaf temperature after ABA application, transpiration rate in the crop field can be estimated by the following equation:
     EL=CpρGEΔTL/λn
    where ΔTL is the rise in leaf temperature after ABA application, n is the coefficient of transpiration depression by ABA application, GE is the conductance for sensible heat transfer, Cpρ is the volumetric heat capacity of air and λ is the latent heat for vaporization. ΔTL and GE can be measured by the micrometeorological Observation using a thermography and anemometers, respectively, and n can be evaluated by using the ABA treated plants. Validity of this evaluation method was demonstrated in the preliminary experiments.
  • Hideyuki MATSUMURA, Chikako MIKAMI, Yasuko SAKAI, Kazutaka MURAYAMA, T ...
    2005 年 60 巻 6 号 p. 1121-1124
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Two-year-old Betula platyphylla Sukatchev var. japonica, three-year-old Betula ermanii Cham., four-year-old Fagus crenata Blume, two-year-old Pinus densiflora Sieb. Et Zucc. And Cryptomeria japonica D. Don seedling were exposed to ambient or elevated ozone (O3) and carbon dioxide (CO2) during two growing seasons (from 12 July to 31 October in 2002 and from 26 March to 31 October in 2003) in Gunma, Japan. Ten open-top chambers were used for five different treatments: filtered air, ambient air (1.0x ambient O3), elevated O3 (1.5x ambient), elevated CO2 (1.5x ambient), and elevated O3 and CO2 combined. At ambient CO2 concentration, growth of all five tree species examined significantly decreased with increasing level of O3. On the other hand, growth of all five tree species in elevated CO2 treatment significantly increased as compared with ambient air treatment. Significant interactions between O3 and CO2 treatment could not be found on the growth parameters of B. ermanii, F. crenata, P. densiflora and C. japonica but on that of B. platyphylla. Elevated CO2 effect on O3- induced growth depression was counteractive on B. platyphylla while not on the other four tree species. Results indicate that responses to elevated O3 and CO2 of growth are species specific.
  • Takeshi IZUTA, Kengo TOMINAGA, Maiko WATANABE, Hideyuki MATSUMURA, Yos ...
    2005 年 60 巻 6 号 p. 1125-1128
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Two-year-old seedlings of Castanopsis cuspidata, Lithocarpus edulis, Quercus glauca and Quercus acuta were grown for two growing seasons in brown forest soil treated with N as NH4NO3 solution at a rate of 0 (N-0), 10 (N-10), 50 (N-50), 100 (N-100) or 300 (N-300) kg ha-1 year-1. Whole-plant dry mass of C. cuspidate and Q. glauca were significantly reduced by the N-100 and N-300 treatments, and by the N-300 treatment, respectively. In L. edulis seedlings, whole-plant dry mass was significantly increased by the N-50 treatment, while it was significantly reduced by the N-300 treatment. Whole-plant dry mass of Q. acuta seedlings increased with increasing amounts of N added to the soil. In C. cuspidate, L. edulis and Q. glauca seedlings, whole-plant dry mass was negatively correlated with the ratio of Mn concentration to Mg concentration (Mn/Mg) in the leaves. In conclusion, there is great difference in the sensitivity to N load among the four evergreen broad-leaved tree species, C. cuspidata being tolerant to high N load, and the concentration ratio of Mn/Mg in the leaves is a useful indicator for evaluating the negative effects of N load on the growth of Japanese evergreen broad-leaved trees.
  • Yasuomi IBARAKI, Junko YAMAGUCHI
    2005 年 60 巻 6 号 p. 1129-1132
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     To develop methods to measure intracellular pH in an attached leaf non-destructively and to construct the pH map when the leaf responds to environment factors, ways of loading fluorescent ion probes into attached leaf cells were tested. Tested fluorescent pH probes included 5-Carboxyfluorescein Diacetate, a ratiometric probe SNARF-1/AM, and a probe for the apoplast FITC-Dextran. Fluorescence of an intact leaf was imaged by a CCD camera attached with a stereomicroscope or by a confbcal laser scanning microscope. Chlorophyll fluorescence analysis and leaf temperature measurements were conducted for evaluating the intensity of leaf damage by introducing the probes. As a result of testing several plant species, it was observed that the feasibility of loading the probes into attached leaf cells depended on species. In the case of species whose cells were easily loaded with the probes, submerging the attached leaf in the probe solution at room temperature for a few hours leaded to bright fluorescence in guard cells, epidermal cells and mesophyll cells. As there was no change in leaf temperature and photochemical efficiency by introducing the probes, it was suspected that no leaf damage was occurred. Path ways through which fluorescent probes can enter into attached leaf cells were also discussed from analysis of the changes in fluorescence distribution patterns in the leaf and from a comparison of the loading results under light and dark conditions.
  • Noriko TAKAHASHI, Kenji KURATA
    2005 年 60 巻 6 号 p. 1133-1135
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Rice yield is sensitive to water stress at the flowering stage, and it is particularly important to study the water status of the panicle due to their sensitivity to water stress. In the panicle, water loss is primarily controlled through the cuticle layer, which contains silica. This suggests that the main role of silica is to suppress transpiration from the leaves. Under ambient atmospheric carbon dioxide concentrations ([CO2]), the role of silica is thus known, but it is unclear how elevated [CO2] affects the role of silica in transpiration.
     We studied the effects of elevated [CO2] (700 µmol mol-1) on transpiration from the rice panicle, and investigated the combined effects of elevated [CO2] and the presence of silica in the culture solution on transpiration from the rice panicle during the flowering stage. Rice plants were grown hydroponically in two artificially illuminated chambers. The transpiration from the rice panicle was measured using the “temperature wave method”. The transpiration from rice panicles decreased under elevated [CO2] and addition of silica to the culture solution reduced transpiration from the panicle regardless of [CO2]. This result suggested that silica may thus contribute to conserving water content in the rice panicle under elevated [CO2].
  • Ryuji TAKEDA, Yoshimasa IKUMA, Sadayoshi MATSUMOTO, Sadao KOMEMUSHI, A ...
    2005 年 60 巻 6 号 p. 1137-1140
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants found in air, sea and river water and soil. Sources of PAHs are thought to include diesel, fossil fuels and power plants. Some PAHs are known to be carcinogenic and mutagenic. Phytoremediation of PAHs is defined as the use of plants and their associated bacteria to remediate contaminated soil. These processes occur on rhizosphere. Plants excrete exudate associated with bacterial activity.
     The relationship of vegetation to PAH concentration was investigated. Two and 3 rings of PAHs, showed high volatility and were not related to vegetation. However, areas with extensive vegetation had lower concentrations of 4 to 6 rings of PAHs.
     Plant responses of pyrene were investigated by superoxide dismutase (SOD) activity. Some plants were collected from sampling spots and steeped in pyrene dissolved in water or distilled water. Most plants showed greater increase in SOD activity when placed in pyrene dissolved in water than when placed distilled water. Especially, Artemisia princeps showed a high level of SOD activity (68.3%). This finding suggested that the substances with high SOD activity participated in degradation of PAHs.
  • Mika EGUCHI, Satoshi YOSHIDA, Jiro CHIKUSHI
    2005 年 60 巻 6 号 p. 1141-1143
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     For an examination of application to trichloroethylene (TCE) phytoremediation in various plant species suitable for wide area in the world, we examined efficiency of a method of screening plant species for ability of TCE phytoremediation, by investigating possibility of TCE degradation in Populus cells of suspension culture. The callus derived from a leaf of Populus nigra var. Italica was grown in MS medium of suspension culture, and TCE was added into the medium. Viability of the Populus cells did not depressed even in the TCE-added medium. At a few days after the TCE treatment, n-hexane extracts of the treated cells and the medium were qualitatively analysed by a gas chromatograph-mass spectrometer, and trichloroethanol (TCOH; an intermediate of TCE in an aerobic bio-degradation) was detected. The intermediate was also detected even when the cells were crushed and then treated TCE, and the degradation ceased by boiling the cell-crushed solution. This fact suggests that TCE in the medium in the Populus suspension culture is degraded through a certain enzyme process of the living cells. Thus, this experimental procedure can be applicable to screening of the useful plant species for TCE phytoremediation.
  • Takashi OYABU, Ayako SAWADA, Hiroyuki KURODA, Tomoaki HASHIMOTO, Takay ...
    2005 年 60 巻 6 号 p. 1145-1148
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     The capabilities of golden pothos and peace lily for air-pollutants were examined. In the experiment, these subjects were installed in an experimental chamber of 300 liters respectively and the purification characteristics were monitored by a tin oxide gas sensor. The responding characteristic of the sensor means a plant purification capability (Pa). And the full-width at a half maximum (tw) of the characteristic was used to evaluate the Pa.
     The Pas of golden pothos and peace lily for toluene and xylene were nearly constant even if the concentrations were changed. The capabilities of golden pothos and peace lily for fromaldehyde became higher as the concentration became higher. Relationship between the tw and molecular weight of the pollutants showed a linear characteristic. It was understood that the purification capability became lower as the molecular weight of the pollutant was larger.
     Plants were also set in a real environment. Total Volatile Organic Compounds (TVOC) and odor grades were measured to examine purification effect of plants. Removal rate for TVOC was 74% and that of odor was 68%. It was confirmed that plants had high purification capability for both of VOCs and odor even in the real environment.
  • Atsushi KUME, Kaneyuki NAKANE, Hiroshi SAKUGAWA
    2005 年 60 巻 6 号 p. 1149-1152
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     This study reconsidered the cause of forest decline of Japanese red pine (Pinus densiflora Sieb. et Zucc.) in the Seto lnland Sea area, western Japan. Although the decline in pine forests was attributed to pine-wood nematode infection, the stress of air pollution was also shown to have negative physiological effects on pine needles. Secondary pollutants related to NOx accumulate in the moming dew then liquid-phase free radicals (・OH) from by photochemical reactions on the needle surface. The stress of polluted dew induces faster needle senescence and defective needle gas exchange. The influence of atmospheric O3 and SO2 was not significant.
     Understory vegetation also had negative physiological effects on the overstory pine needles through competition of roots for water and nutrients. Abandonment of management accelerates growth of understory vegetation causing decline of P. densiflora plantations. Each of these stresses was shown to independently and significantly reduce needle photosynthesis, which consequently seemed to reduce pine resistance to pathogens.
     In many cases, air pollution and progressing succession have not been considered as important causes of P. densiflora decline. Careful on-site atmospheric chemical and eco-physiological measurements are therefore important for accurate evaluations of the conditions of pine growth and the causes of decline.
  • Choong Hwa LEE, Seung-Woo LEE, Eun-Young KIM, Jin-Heon JEONG, Hyun-Je ...
    2005 年 60 巻 6 号 p. 1153-1156
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Although a large area of forest damage due to acid deposition have not yet been found in South Korea, but some of local tree declines have been frequently reported especially for Pinus densiflora (Japanese red pine), the most common coniferous tree. In the present study, we evaluated the effects of acid deposition on forest, results of ambient SO2, acid load, soil pH and tree decline monitored from 1988 to 2001 in urban, industrial and mountainous area along the gradient of atmospheric pollution were compared. During the study period, annual mean SO2 concentrations in urban area averaged 13ppb with a maximum of 31ppb, 1989 and industrial and mountainous area averaged 14ppb and 6ppb, respectively. Annual mean acid loads were 0.09 and 0.11 kmol H+ ha-1 in urban and industrial area, significantly comparable with 0.03 kmol H+ ha-1 in mountainous. The surface soil of the red pine forest in urban and industrial area was acidified (pH 4.1-4.3), whereas pH 5.4 in mountainous area. On the other hand, based on defoliation and discoloration measured in l996 and 2001, decline degree of the pine trees in two polluted areas was higher than that in mountainous area. The data indicate that the combined effects of high air pollution and acid deposition-induced soil acidification (possibly Ca deficit and Al toxicity) could adversely influence the Japanese red pine.
  • Brenden E. McNEIL, Jane M. READ, Charles T. DRISCOLL
    2005 年 60 巻 6 号 p. 1157-1160
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     The concentration of nitrogen in leaves, or fbliar N, can be remotely measured from space-borne hyperspectral remote sensing instruments, and is theorized to be the best indicator of an ecosystem’s N status, or ability to retain inputs of N from atmospheric deposition. However, interpretation of foliar N measurements becomes increasingly complicated at broad scales due to its poorly-understood variability through space and time. We present an approach that minimized temporal variability in order to identify controls on the spatial variation in foliar N within diverse forested ecosystems along a two-fold N deposition gradient within the 2.5 million hectare Adirondack Park, NY. As an example of results obtained with this approach, we discuss the highly significant, positive relationships observed between foliar N and N deposition in five of seven major Adirondack forest species. From these relationships, we conclude that regional gradients of N deposition can explain a large part of the spatial variation in foliar N, but their ability to do so is species dependent. A species’ foliar N response to N deposition may be determined by its functional group and its position along a spectrum of shade tolerance.
  • Jun-ichi MOGAMI, Takashi HIRANO, Ryuichi HIRATA, Satoshi KITAOKA, Taka ...
    2005 年 60 巻 6 号 p. 1161-1163
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     The field experiment was conducted in a larch forest to investigate temporal and spatial variations in photosynthetic photon flux density (PPFD) on the forest floor (PPFDf) and the phenological pattern of PPFDf. PPFD was measured at seven points on the forest floor at height of 1 m and at one point above the canopy (PPFDc) at 10 Hz from 18 April to 30 September in 2002. PPFDf was expressed as %PPFD, which is the percentage of PPFDc. %PPFD decreased as PPFDc increased and became almost constant over PPFDc of 500 µmol m-2 s-1 throughout the measurement period. The relationship was well fitted by a rectangular hyperbola. Temporal and spatial variations in %PPFD increased exponentially with PPFDc and increased with LAI.
  • Takuya FUJII, Kenji KURATA, Kazuhiro FUJIWARA, Keiko OHASHI, Takeki EM ...
    2005 年 60 巻 6 号 p. 1165-1167
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Effects of frequency and time of mowing and/or uprooting on the average plant numbers per square meters (plant density) and plant height of Goldenrods (Solidago altissima L.) were investigated. In total eight treatments were tested: M5 (mowing in May), M10M5 (mowing in Oct. in the previous year and in May), M11M5 (mowing in Nov. in the previous year and May), M3M5 (mowing in March and May), U10M5 (uprooting in Oct. in the previous year and mowing in May), U11M5 (uprooting in Nov. in the previous year and mowing in May), U3M5 (uprooting in March and mowing in May), U5 (uprooting in May). The average plant density and plant height were measured in August. The results indicated that there were no statistically significant differences in the plant density among the treatments, except for M5 (the largest), suggesting that the plant density was not much affected by the time of mowing and/or uprooting. On the contrary, the plant height was more affected by the weeding methods (mowing or uprooting) and the time of weeding. The results also suggested that treatments including uprooting were more effective in reducing the plant height than mowing-only treatments. The most effective treatment among those tested was U10M5. Among mowing-only treatments, M10M5 was the most effective.
  • Fulu TAO, Masayuki YOKOZAWA
    2005 年 60 巻 6 号 p. 1169-1174
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Climate change and soil degradation are two major, and interrelated global environmental challenges for water resources and agricultural production in China in the coming decades. In the present study, we used a crop-specific water balance model and sets of updated datasets to assess the interactive impacts of climate change and soil degradation on agricultural water resources and agricultural production in China. The results show that both climate change and soil degradation would have major influences on agricultural production in China in the 2020s. Under combined impacts of climate change and soil degradation, soil moisture deficit would increase in north and northeast China by more than 20 mm generally. Yield index would decrease by more than 5% in north, northeast and southwest China. Climate change would dominate the general change pattern, however at some local regions where soil degradation became a problem, the impacts of soil degradation would be at the same order as those by climate change. From 2001 to 2080, in the North China Plain, there would be an obvious warming trend. Precipitation will fluctuate during the period. Yield index and water deficit also fluctuate during the period. Water resources will became severe during several periods in the region, which however depend on scenarios. Since climate change is likely to interact with other global changes, including population growth and migration, economic growth, urbanization, and changes in land use and resource degradation, more integrated process-based model should be developed in further studies to capture feedback mechanisms and social economic effects more effectively.
  • Yutaka URANO, Kenji OMASA
    2005 年 60 巻 6 号 p. 1175-1177
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Estimation of carbon sinks in forest is important to understand global climatic changes such as global warming. The amount of carbon sinks is often explained by biomass, which can be calculated by DBH (Diameter at Breast Height) of each tree. However, measuring exact DBH of standing trees by existing methods is tedious and takes longer time. Hence, studies have been carrying on developing the methodology to measure DBH and biomass.
     In this study, a ground-based remote sensing technique to measure tree stem diameters and biomass in forest has been developed using portable imaging lidar data. Forty 60-year-old Japanese cedars (Cryptomeria japonica) in a study site of 400 m2 were measured to estimate DBH and biomass (carbon weight).
     As a result, each DBH of 31 trees (other 9 are in dead angle) was measured with RMSE (Root Mean Square Error) of 6.1 mm. The biomass of individual tree was calculated with RMSE of 11.5 kgC. Total biomass in entire study site including 9 trees in dead angle was estimated by percent method within the error of 3%. It can therefore be concluded that the methodology using a lidar can efficiently replace existing methods to measure DBH and carbon sinks with high accuracy.
  • Kotaro TAKAYAMA, Kenji OMASA
    2005 年 60 巻 6 号 p. 1179-1181
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     The effects of Basta, a commercially available foliar-application type herbicide, on a in situ Phaseolus vulgaris L. leaf was analysed with the chlorophyll fluorescence and thermal imaging system. The images of photosynthetic electron transport activity in photosystem II (ΦPSII) and leaf temperature across a leaf surface were obtained before and after the herbicide treatment. At 30 min after the treatment, ΦPSII began to decease in several sites within the treated region although the leaf temperature did not change. At 60 min after the treatment, the leaf temperature gradually increased at the sites whereΦPSII had markedly decreased. Those results showed that theΦPSII primarily decreased and the leaf temperature increased after the Basta treatment. This suggests that Basta initially inhibited the photosynthetic electron transport activity and the inhibition caused the stomatal closure. This study demonstrated that the early detection and detailed analysis of the physiological damage caused by herbicide are possible using the chlorophyll fluorescence and thermal imaging system.
  • Aki YAMANISHI, Atsushi TSUNEKAWA, Yutaka KIYOHARA, Takashi KAMUO, Hiro ...
    2005 年 60 巻 6 号 p. 1183-1188
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Mt. Oyama on Miyake Island, in the Izu Islands of Japan, erupted in 2000. Indigenous plants and animals were badly affected by the volcanic deposits and gases. We analyzed satellite images to estimate vegetation cover and to assess long-term vegetation damage on the island. We then classified changes in vegetation cover between l995 and 2003 and compared the classification with field survey data.
     We compared fractional vegetation cover (fC) interpreted from aerial photographs with cover estimated from remote sensing data to select the best equation for estimating fC. The following equation best estimates vegetation cover on Miyake Island:
     fC=[(NDVI-NDVImin)/(NDVImax-NDVImin)]2 × 100%
    where NDVI is the Normalized Difference Vegetation Index, and NDVImin and NDVImax are the minimum and maximum values.
     We estimated vegetation cover on Miyake Island using this equation and by analyzing 8 satellite images from 1995 to 2003. The main phases of volcanic activity occurred from July to August 2000, when almost all vegetation was damaged, mainly by volcanic ash. On the foothills of the mountain, vegetation damaged by volcanic ash gradually recovered. However, damage has spread along the eastern part of the mountain since autumn 2000, probably owing to the volcanic gases emitted since September 2000.
     Vegetation cover was classified from 6 satellite images from 2000 to 2003. Vegetation was classified into 6 classes based on the change of vegetation cover. The state of vegetation damage in each area corresponded well with the results of the field survey. In almost all areas, species composition changed after the eruption. The classification map will provide basic data for conservation efforts and recovery.
  • Hardy PFANZ, Volker TANK, Dominik VODNIK
    2005 年 60 巻 6 号 p. 1189-1192
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Plants growing within mofette fields (CO2 emitting gas vents) show specific adaptations according to their extreme habitat. The closer they grow to the gas emitting vents and the higher the concentration of the escaping CO2 gas, the smaller the actual height and the total biomass of the plants. For some species a concomitant decrease in total chlorophyll was found. Additionally, photosynthesis as measured using CO2 gas-exchange and fluorescence clearly followed the same rule, being higher at the margins of the area and lower close to the vents. As fluorescence can be detected via remote sensors, chlorophyll fluorescence may be used to detect physiological changes from remote. In addition an abiotic thermal parameter may help in recognizing mofettes in the field. As the flux of escaping CO2 gas from the soil may influence the soil temperature at and around the vent openings the application of infrared thermovision systems may be used to confirm their existence or detect unknown ones. The emerging gas dampens the temperature fluctuations of the soil imposed by the weather: it will cool the soil, when the gas is cooler than the undisturbed surface and it will warm the soil when the gas is warmer. Subtraction of multi-temporal IR images and setting temperature difference thresholds in difference images allows to disclose this effect and thus to detect the vents as well as their spatial extension.
  • Hardy PFANZ, Guido ASCHAN, Stephan KERKIEN, Bohumir LOMSKY, Christiane ...
    2005 年 60 巻 6 号 p. 1193-1195
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Gaseous air pollutants penetrate stomata in leaves and lenticels in stems, thus reaching the mesophyllic or parenchymal interior of the organs. As inner bark tissues in young limbs are able to perform photosynthesis, the effects of different air pollutants to chlorenchymal photosynthesis were examined. Short time exposure to selected air pollutants was studied in the aqueous phase and the inhibitory concentrations were compared between leaf, stem, bark and proper wood photosynthesis. Peridermal tissues proved to be effective barriers for pollutant diffusion. Photosynthetic cells of the proper wood seemed to be most tolerant, a fact that needs further studies.
  • Maria del Carmen MLDES, Minoru INAMURA
    2005 年 60 巻 6 号 p. 1197-1200
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     We present a practical multidimensional framework for obtaining a super-resolution image from a subpixel shifted sequence through the reduction of noise followed by a recursive back-projection algorithm.
     The noise-reduction stage, for thermal patterns, uses the multi-observation for identifying the fixed pattern noise. As an alternative, we present a neighborhood classification method that identifies the type and degree of the fixed noise that is subtracted from the image. In the case of radar and ultrasonic images, the multiplicative speckle noise is reduced with a filter that adaptively calculates the size of the filtering window and performs a median filter only considering the pixels with similar values inside the window.
     The super-resolution technique performs the downsampling of the pre-processed image sequences followed by a back-projection algorithm. Different evaluation methods demonstrate the accuracy and quality of the results. Finally, we propose a multireflecting system adapted to the camera, provided with a rotational scanning as a hardware solution for the data acquisition stage.
  • Maria del Carmen VAIDES, Minoru INAMURA
    2005 年 60 巻 6 号 p. 1201-1205
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     We evaluate the results of the application of several filters already known, modified by means of adding adaptive mechanisms based on the statistical properties of the noise. We also demonstrate that some adaptive and/or recursive filters designed for reducing the speckle noise can be improved with a two-stages filtering process. The conventional filters that have served as basis for our study are tabulated and the results are evaluated.
  • Tsutomu AWADU, Kazuo OKI, Kenji OMASA
    2005 年 60 巻 6 号 p. 1207-1210
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     In previous research a singular value decomposing method with some restraint conditions was used to estimate unknown endmembers and coverage in agricultural land. However, it is limited to the ideal case I which observed spectra don’t include noise. Hence it is necessary to verify the feasibility of this method to spectra obtained from agricultural area.
     In agricultural area, two cases are assumed: observed spectra have a large and a small deviation. If observed spectra have a large deviation, it is more difficult to estimate endmembers. However estimating endmembers is possible using the singular value decomposing method even if observed spectra have a large one. Consequently, it is showed that this method is applicable to even real agricultural land.
     Additionally, a new index of plant characteristic was proposed. NDVI (Normalized Difference Vegetation Index) has used in evaluating plant characteristic as usual, however it is affected by coverage significantly. Some researches have reported that NDVI expresses the plant characteristic when the influence of coverage can be neglected. In this study, the influence of coverage was removed to express degree of plant activity numerically.
  • Shin NAGAI, Kazuhito ICHII, Hiroshi MORIMOTO
    2005 年 60 巻 6 号 p. 1211-1214
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     Carbon cycle of tropical ecosystems may respond from climate variations related to El Nino-Southern Oscillation (ENSO). Although models and atmospheric studies have demonstrated the relationship, few studies have been conducted using direct observations on large spatial scales. In the present study, the interannual variations associated with ENSO period in the satellite-based Normalized Difference Vegetation Index (NDVI) data over low latitudinal zones (30゚N to 30゚S) from 1981 to 2000 were analyzed using Singular Spectrum Analysis (SSA), which is an effective method to extract the variations from short-term noisy time-series data.
     The NDVI variations over tropical rainforest are characterized by a high proportion of variances explained by ENSO time-scale mode, although the original NDVI data also contained the seasonal variations. In addition, these variations show a high correlation with Southern Oscillation Index (SOI) variation.
     We concluded that the long-term satellite observation also shows the impact of ENSO-related climate variations on terrestrial vegetation activities.
  • Shan LU, Kazuo OKI, Kenji OMASA
    2005 年 60 巻 6 号 p. 1215-1218
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     A method for mapping snow cover using Advanced Very High Resolution Radiometer (AVHRR)/Normalized Difference Vegetation Index (NDVI) 10-day composite data was developed at the continental scale. The 10-day AVHRR/NDVI composite data and snow depth data of AmeDas (Automated Meteorological Data Acquisition System) in l999 were compared to extract the snow cover land surface by determining NDVI threshold values. Initially, one threshold value was applied to all overJapan. However, the results showed inaccuracies in snow map for the different land cover effects the NDVI values greatly. To improve the estimation accuracy, classifying the land cover into 5 categories was conducted. The snow maps derived from different threshold values for different land cover categories instead of one threshold value for all over Japan showed better accuracy. The areas where the accuracy of mapping got better are in the forest area such as alpine vegetation and urban area especially around Kanto.
  • Kazuo OKI, Ikuro KATO, Kenji OMASA
    2005 年 60 巻 6 号 p. 1219-1221
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     In this paper, snow depth in Kushiro area, the largest wetland in Japan, was estimated using L-Band SAR imagery. The SAR imagery can be used to observe land condition regardless of the weather condition. The accuracy of SAR however, is affected by topography or surface roughness. To remove the effects of topography or surface roughness, we applied the principal component analysis (PCA) to the SAR imagery. As a result, it was found that the proposed method could effectively estimate snow depth using SAR imagery because one principal component image of SAR calculated by PCA include the snow depth information without the effects of topography or surface roughness.
  • Tomohiro HAJIMA, Yo SHIMIZU, Yoshitaka FUJITA, Kenji OMASA
    2005 年 60 巻 6 号 p. 1223-1225
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     The Bio-Geographical and GeoChemical model (BGGC) is a process-based mathematical model that can be used to assess future impacts of climate change on the distribution and functioning of terrestrial ecosystems. This model can simulate the cycling and fluxes of carbon and nitrogen in vegetation, soils and exchanges with atmosphere, as well as estimate potential distribution of natural vegetations. One of the strengths of the BGGC model is to estimate net primary production (NPP) under scenarios where nitrogen is limiting. This is accomplished by a material cycling module that can simulate processes of vegetation competition due to nitrogen limitation. The objective of this study was to use BGGC model under various climate change scenarios to test its applicability in evaluating changes in NPP with limiting nitrogen availability across the diverse geographical regions of Japan.
     Results of simulation showed that nitrogen interacts with elevated CO2 and temperature, decreasing NPP with increasing nitrogen limitations. The terrestrial ecosystem was generally predicted to be a net sink for carbon but it could be over-estimated without the nitrogen limiting the photosynthesis.
  • Akira NASU, Yo SHIMIZU, Kenji OMASA
    2005 年 60 巻 6 号 p. 1227-1229
    発行日: 2005年
    公開日: 2016/12/30
    ジャーナル フリー
     This study was conducted to verify the relationship between the shifts in plant phenology and changes in air temperature over a 40-year (1961-2001) period in Japan. Daily mean air temperature and annual phenological data (1961-2001) from 101 meteorological stations of the Japan Meteorological Agency were used in this study. The phenological data consists of both springtime phases such as flowering and full flowering, autumn phases such as leaf coloring and leaf fall of trees.
     We considered influences of daily temperature being just closed to the date of phenological events, therefore the anomalies of daily mean air temperature between 1961 and 2001 were used. The length of periods during which air temperature affects phenological events was determined by maximization of the correlation coefficients between the cumulated anomalies prior to the date of each phenological event and to the data of each phenological event from 1961 to 2001 by the linear regression.
     From the 16 types of plant phenology, the lalgest was 0.88 for Prunus yedoensis Matsum. flowering. The length of periods with maximum correlation coefficient differed from plant phenology. Results of the analysis suggest that some phenological trends reflected responses to climate change in Japan.
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