日本リモートセンシング学会誌
Online ISSN : 1883-1184
Print ISSN : 0289-7911
ISSN-L : 0289-7911
22 巻 , 5 号
選択された号の論文の12件中1~12を表示しています
  • 山形 与志樹, 小熊 宏之, 関根 秀真, 土田 聡
    2002 年 22 巻 5 号 p. 494-509
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    The carbon sink issues under the Kyoto Protocol had been negotiated intensively since COP3 until the agreement at COPT. Although, one of the largest carbon sink activities (3.9%) are allowed for Japan to achieve the reduction target (6%), there are still many issues need to be addressed regarding the implementation, such as additional forest management, development of the carbon accounting system etc. Especially, regarding the monitoring of the carbon sink activities, the Kyoto Protocol mandates each countries to report in a transparent and verifiable manner. In this regard, it is expected that the remote sensing techniques play a major role in establishing the carbon sink assessment system to meet the need of the Kyoto Protocol and beyond. This report review the international agreement associated with the carbon sink article, the cutting edge methods for the carbon sink assessment, and the related international research activities.
  • 沖 一雄, 小熊 宏之
    2002 年 22 巻 5 号 p. 510-516
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    A method for estimating the canopy coverage of, forest by remote sensing techniques has been required. To illustrate, the Kyoto protocol adopted in 1997 has shown that it is important to calculate CO2 absorption of the forest. To calculate CO2, it is necessary to accurately estimate the canopy area of specific forest. Therefore, remote sensing techniques, which can observe wide ranges periodically, have been expected to estimate canopy coverage of specific forest.
    In this paper, we propose an improved matched filter method for estimating canopy coverage of alder trees in a forest located in the Kushiro mire using remotely sensed imagery. The conventional matched filter method has been problem for estimating specific vegetation, because there are the effects of various vegetations within a single pixel. However, the canopy coverage of alder trees in the Kushiro was able to be estimated by the proposed method which removes the effects of other vegetation.
  • 関根 秀真, 山形 与志樹, 小熊 宏之
    2002 年 22 巻 5 号 p. 517-530
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    The Kyoto Protocol allows some carbon sequestration by vegetation sinks to be offset against CO2 emissions. The sink projects under Joint Implementation (JI) and Clean Development Mechanism (CDM) are indispensable to achieve the emissions target of our country (-6% from the 1990 total).
    In order to make the sink project successful, an evaluation of forestation and a monitoring and a verification of the carbon sink are critical factors. In this report, the impact study of forestation business in Green Triangle region of Australia was implemented by using multi-temporal Landsat/TM and ETM+ data. Green Triangle region is one of the potential areas of sink project for afforesttaion and reforestation of Article 3.3 clause of the Kyoto Protocol. The evaluation approach of the forest area based on the definition of the Kyoto Protocol was discussed for these areas.
    Furthermore, we examined the practical use of satellite remote sensing technology for Kyoto Protocol by organizing the necessary condition of the sink and defining a process and items needed for monitoring.
  • 米 康充, 小熊 宏之, 山形 与志樹
    2002 年 22 巻 5 号 p. 531-543
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    Todevelop a monitoring system for carbon sinks under the Kyoto Protocol, a method of forest stand measurement using Airborne Lidar sensor is examined. A canopy DSM (Digital Surface Model) was constructed from first pulse of the lidar data, and the DTM (Digital Terrain Model) was constructed from the last pulse of the lidar data. The tree height surface was made from the difference of the canopy DSM and DTM. Crowns of trees were extracted from the tree height surface by the Watershed method. Numbers of stand trees were counted from the crowns. Tree heights were measured from height surface within the crown. Stem volumes of trees were calculated from the relationship between tree height and stem volume, from a yield-density effect curve, and from an aerial photographical analysis table. Carbon weights were calculated by using the relationship between the stem volumes and dry weights and the coefficient of carbon inclusion.
    The results are : 1) The measurement error of tree height of Larix leptolepis stand was less than about 0.3 m (accuracy) and 1.0 m (precision). The precision of the measurement was assumed to be originated from the precision of truth data ; 2) the extracted crowns of trees were canopy trees, not understory trees, and the number of extracted crown had a tendency to be underestimated ; 3) stem volumes and carbon weights were underestimated by using the relationship between the tree heights and stem volumes and the yield-density effect curve. Using aerial photographical analysis table, however, yielded better results.
    The next steps of this study will be 1) to develop of a method of the extraction technique from the lidar points with more accuracies, and 2) to develop of a method of aerial photographical analysis to estimate carbon weights for wide areas.
  • 洲濱 智幸
    2002 年 22 巻 5 号 p. 544-549
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    Integrated monitoring systems for forest biomass are necessary to estimate carbon stock changes in a forest area. This paper introduces airborne remote sensing technology to estimate the forest biomass and overview the development of aircraft platform for multiple sensors.
    Although no specific forestration guidelines have been decided to utilize a cost-effective approach to ensure carbon dioxide emission curbing targets, technology development to detect carbon stock change should be carried out as priority strategy. This will bring the business opportunity, and also will contribute to global warming countermeasures.
  • 大政 謙次, 浦野 豊, 小熊 宏之, 藤沼 康実
    2002 年 22 巻 5 号 p. 550-557
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    In natural woody conditions, measuring tree position and diameter at breast height (DBH) of each Larix leptolepis by a portable scanning lidar is not easy because the tree is covered with not only their own thick branches but also other plants such as small broad-leaved trees, vines, epiphytes and quite tall ferns. Therefore, new methods for mapping tree position of Larix leptolepis woods and estimating the DBH using the range data of measurable tree parts obtained by a portable scanning lidar with high spatial resolution were examined. Furthermore, biomass of the trees was estimated from the DBH.
    Using the range data measured by the portable scanning lidar that was set at a point in the woods, each tree position was mapped. Within the area of the angle of 170 degrees horizontally and 10m from the lidar, the number of measurable trees was 14 (100% of all trees in the area), within the area of 15m the number was 24 (83%), within the area of 20m the number was 29 (66%), and within the area of 30m the number was 44 (45%). Then the DBH of each tree was estimated in error of RMSE=7.3mm from the trunk diameter measured at a certain height of the tree using Eq. (1), where the coefficient k (h) had been obtained beforehand. Also, the biomass (fresh, dry and carbon weight) of each tree was estimated from the DBH using a quadratic equation (R2=0.96) correlated between DBH and biomass above ground. Furthermore, the biomass per square meter was estimated in error of 2.7% within the area of 30m from the lidar. The fresh weight and the carbon weight were obtained from the dry weight multiplied by 1.7 and 0.45 respectively.
  • 尾西 恭亮, 六川 修一, 加藤 俶史
    2002 年 22 巻 5 号 p. 558-570
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    One of the serious problems of the Kyoto Protocol is that we have no effective method to estimate the carbon stock of the subsurface. To solve this problem, we propose the application of ground-penetrating radar (GPR) to the subsurface soil survey. As a result, it is shown that GPR can detect the soil horizons, stones and roots. The fluctuations of the soil horizons in the forest are clealy indicated as the reflection pattern of the microwaves. Considering the fact that the physical, chemical, and biological characteristics of each soil layer is almost unique, GPR results can be used to estimate the carbon stock in soil by combining with the vertical soil sample survey at one site. Then as a trial, we demonstrate to estimate the carbon content fixed in soil layers based on the soil samples and GPR survey data. we also compare this result with the carbon stock for the flat horizon case. The advantages of GPR usage for this object are not only the reduction of uncertainty and the cost, but also the environmental friendliness of survey manner. Finally, we summarize the adaptabilities of various antennas having different predominant frequencies for the shallow subsurface zone.
  • 小林 史歩, 六川 修一, 山形 与志樹, 小熊 宏之
    2002 年 22 巻 5 号 p. 571-587
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    In this article, our object is to predict biochemical contents (chlorophyll, water, nitrogen, lignin and cellulose) of larch needles from their spectral characteristics, because larch tree is a kind of important trees as sink for CO2. We firstly tested whether conifer leaf Model LIBERTY, which was constructed on jack pine and slash pine needles by Dawson et al., (1998), can predict quasi-infinite reflectance for larch needles from biochemical contents or not. And we established the way to predict respectively biochemical contents from global absorption coefficient, because LIBERTY Inversion model, which was constructed by Dawson et al., can predict just global absorption coefficient for cells from quasi-infinite reflectance. In conclusion, we could predict respectively biochemical contents from quasi-infinite reflectance for larch needles, and we suggested that there is the probability to predict them more accuracy, if 1) we modify LIBERTY model more suitable for larch needles, 2) incorporate carotenoid absorption coefficient into the model 3) get more data sets for larch needles and so on.
  • 小熊 宏之, 土田 聡, 藤沼 康実
    2002 年 22 巻 5 号 p. 588-597
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    The hyper-spectral reflectance factor over the forest canopy is expected to obtain the information, which is related to the health condition, leaf biochemical contents ratio and photosynthetic activity. A hyper spectral digital camera system was developed in order to automatically take the hyper-spectral images of the forest in the daytime. This paper describes the outline of this camera system and initial result of acquired images of Tomakomai Flux research site. Spectral diffraction camera and autorotation stage and mainly constitute this system.
    The camera has been installed in the top of the tower of the 25 m heights. The image acquisition is carried out from 8a.m. to 6p.m. in the 2-hour interval. This system covers the wavelength range from approximately 520 nm to 850 nm with a spectral resolution of 5nm. In 2001, the observation was carried out between September to the end of November.
  • 土田 聡, 小熊 宏之
    2002 年 22 巻 5 号 p. 598-611
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    A prototype fisheye camera is a hemispheric radiometer that was developed as a proto-flight model for the hot spot observation in canopy reflectance. This camera consists of the CCD camera and the fisheye lens that can measure the surface radiation with high resolution in instantaneous field of view in a short time. The averaged image calculated from a large number of the images measured in a short time shows detailed characteristics of surface reflectance in hot spot. This paper describes the design, calibration, and first measurements, which were carried out in visible and near infrared region at the Tomakomai flux research site, of the prototype fisheye camera.
  • 小林 秀樹, 松永 恒雄, 梅干 野晁
    2002 年 22 巻 5 号 p. 612-624
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    本研究では,まずTOMS/PAR法の基礎検討により,Ruvに対するRsの影響と,標高の変化に伴うPARclearの変化が無視できないことを指摘し,改良TOMS/PAR法を提案した。また,TOMS/PAR法と改良TOMS/PAR法でのPAR推定精度の違いを気象庁の観測値を用いて検証し,後者の場合,より妥当なPAR推定値が得られる事が確認できた。
    さらにMODISのFPARプロダクトとTOMS/PAR法及び改良TOMS/PAR法によるPAR推定値を用いてAPARを算出し,APAR推定誤差がNPP推定誤差に与える影響を評価した。その結果,ランダム誤差は最大で年間NPPの4%程度,バイアス誤差が4-6%(MODIS/FPAR+改良TOMS/PAR法),8-9%(MODIS/FPAR+TOMS/PAR法)であった。これらの検討から,TOMS/PAR法,改良TOMS/PAR法ともに,既往研究における年間NPPのモデル間のCVよりは小さく,現在のAPAR推定値は全球NPP推定値の算出に対して十分な精度を持っていることが示された。しかし,年間NPPの全球推定にあたって,不確実性を低減させるためには,様々な地表面の紫外線反射率の影響を受けにくい改良TOMS/PAR法を用いた方がより信頼できる値を得られる。
  • 市井 和仁, 松井 洋平, 村上 和隆, 山口 靖, 小川 克郎
    2002 年 22 巻 5 号 p. 625-636
    発行日: 2002/12/31
    公開日: 2009/05/22
    ジャーナル フリー
    これまで大気CO2濃度の予測等に用いられてきたシンプルモデルは,生物圏における炭素循環素過程の経年変動データが不足していたために,生物圏に関して十分な検証が行われていなかった。本研究では,過去20年程度のAVHRRデータを利用して全球NPPの変動を解析し,一方では炭素一エネルギー循環結合モデルを構築し,両アプローチの相互検証を行った上で信頼性を確認した上で,将来予測を行った。
    過去のNPPトレンドに関して,気候フィードバックを考慮したモデルでは,考慮しないモデルに比較して,衛星データの結果により近い結果を示した。従って,気候フィードバック効果を導入したことは,妥当であったと結論付けられる。しかし,衛星データから算出されたNPPのトレンドは,モデルから求めた値よりも依然として大きな値である。気候フィードバック効果を考慮したモデルと比較しても2.5倍の開きがあるので,双手法のさらなる改善が必要である。衛星データについては,不十分な大気補正や地表面BRDF補正等の様々なデータ品質の改善が必要である。4-SCEMについては,過去の大気CO2との不一致の改善や,窒素による肥沃化効果,水分条件の考慮等が必要である。
    将来のCO2濃度や気温の予測の結果,ISAM等他のモデルと比較して,2100年時点で大きな違いは見られなかった。しかし,NPP等の生物圏プロセスについても検証を行うことにより生物圏についても簡単ながら議論ができるようになり,モデルの精度向上と改善へとっながった。
    リモートセンシングデータは,過去20年以上にわたって高い時間・空間分解能の地表面等の情報を与えてくれる唯一のデータである。現段階では,衛星データを用いて生物圏等の経年変動や長期トレンドをモニタリングするためには,依然としてノイズが大きく精度が十分でないため,補正等によるS/N比の向上が非常に重要である。現在の地球環境の将来予測モデルでは,生物圏炭素収支の経年変動データが不足しているために,生物圏モデルに十分な制約を与えていない。今後,リモートセンシング等によるより精度の高いグローバルモニタリングにより,モデルにより強い制約を与え,さらには,大気CO2濃度や気温,各炭素循環プロセスにっいて,より正確な将来予測を行うことが可能となる。
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