Heritability estimates for wood stiffness and its related near-infrared spectral bands in sugi (Cryptomeria japonica) clones

2015 ◽  
Vol 20 (1) ◽  
pp. 206-212 ◽  
Author(s):  
Takaaki Fujimoto ◽  
Keisuke Chiyoda ◽  
Kazuho Yamaguchi ◽  
Keiya Isoda
2015 ◽  
Vol 45 (8) ◽  
pp. 1077-1085 ◽  
Author(s):  
Nea Kuusinen ◽  
Pauline Stenberg ◽  
Erkki Tomppo ◽  
Pierre Bernier ◽  
Frank Berninger

Inherent variability in the spectral properties of boreal forests complicates the retrieval of canopy properties such as canopy leaf area index from satellite images. Understanding the drivers of this variability could help provide better estimates of desired canopy cover properties. Field plot data from the Finnish National Forest Inventory and Landsat thematic mapper (TM) images were used to investigate the variation in canopy and understory reflectance during stand development in coniferous boreal forests. Spectral data for each plot were obtained from the Landsat pixel within which the plot center coordinates fell. Nonlinear unmixing was used to estimate the bidirectional reflectance factors (BRFs) of the “sunlit understory” and “canopy and shaded ground” components by site fertility and stand development classes. A forest albedo model was used to estimate the contribution of diffuse radiation reflected downwards from the canopy to the sunlit understory component. The sunlit understory BRF in the near-infrared spectral band decreased as the site fertility decreased and the forest matured, whereas the sunlit understory BRFs in the red and shortwave-infrared spectral bands concurrently increased. The BRFs of the canopy and shaded ground component decreased slightly during stand development, mostly in the near-infrared spectral band. Adding the diffuse contribution to the sunlit understory component changed the estimated component BRFs only a little (0.1%–1.7%) compared with those obtained using a linear mixing assumption. This effect was largest in the near-infrared spectral band and smallest in the red spectral band. For Norway spruce plots, the measured and estimated forest variables were well correlated with the BRFs in all of the studied spectral bands, but for the Scots pine plots, the correlations were notably weaker. Results show a greater importance of the fraction of visible sunlit understory on forest reflectance in Scots pine than in Norway spruce forests.


Geophysics ◽  
1987 ◽  
Vol 52 (7) ◽  
pp. 924-930 ◽  
Author(s):  
M. Dennis Krohn ◽  
Stephen P. Altaner

Diagnostic near‐infrared spectral features have been identified for minerals with ammonium [Formula: see text] bound in the crystal structure. Spectral bands near 2.12, 2.02, and 1.56 μm are characteristic of synthetic and natural [Formula: see text] minerals. Laboratory spectra of [Formula: see text] minerals are distinct from spectra of OH‐bearing minerals and have diagnostic shifts in band position among different mineral types. [Formula: see text] minerals were detected at several mineralized hot‐spring deposits in the western U.S. by means of hand‐held and airborne instruments. Near‐infrared detection of [Formula: see text] minerals may provide useful information for prospecting for certain ore deposits and may provide a better understanding of the nitrogen cycle within geologic environments.


2011 ◽  
Vol 83 (4) ◽  
pp. 1231-1242 ◽  
Author(s):  
Sílvia N. M. Yanagi ◽  
Marcos H. Costa

This study evaluates the sensitivity of the surface albedo simulated by the Integrated Biosphere Simulator (IBIS) to a set of Amazonian tropical rainforest canopy architectural and optical parameters. The parameters tested in this study are the orientation and reflectance of the leaves of upper and lower canopies in the visible (VIS) and near-infrared (NIR) spectral bands. The results are evaluated against albedo measurements taken above the K34 site at the INPA (Instituto Nacional de Pesquisas da Amazônia) Cuieiras Biological Reserve. The sensitivity analysis indicates a strong response to the upper canopy leaves orientation (x up) and to the reflectivity in the near-infrared spectral band (rNIR,up), a smaller sensitivity to the reflectivity in the visible spectral band (rVIS,up) and no sensitivity at all to the lower canopy parameters, which is consistent with the canopy structure. The combination of parameters that minimized the Root Mean Square Error and mean relative error are Xup = 0.86, rVIS,up = 0.062 and rNIR,up = 0.275. The parameterizations performed resulted in successful simulations of tropical rainforest albedo by IBIS, indicating its potential to simulate the canopy radiative transfer for narrow spectral bands and permitting close comparison with remote sensing products.


1994 ◽  
Vol 143 ◽  
pp. 70-71
Author(s):  
Gerard Thuillier ◽  
Michel Herse ◽  
Dietrich Labs ◽  
Paul C. Simon ◽  
Didier Gillotay ◽  
...  

For the ATLAS and EURECA missions, we have used two identical instruments to measure the absolute solar spectral irradiance from 180 to 3200 nm. These instruments are calibrated by use of a blackbody and a set of lamp standards. The measurements are carried out with 1 nm bandpass up to 800 nm and 20 nm above. The instruments and calibration procedures are described by Thuillier et al. (1981). The platform capability of instruments retrieval after measurements allows a post-flight calibration which is essential for accurate measurements. The main results obtained up to now are:- In the UV, the ATLAS-1 and EURECA-1 solar spectral irradiance are consistent with the SpaceLab 1 data obtained in 1983 (Labs et al. 1987). Figure 1 shows the ATLAS 1 and SL 1 spectra. The origin of the existing differences is presently under investigation.- In the visible domain, our measurements agree with the solar spectrum from Neckel & Labs (1984) within a few percent difference at certain wavelength.- In the IR domain, the preliminary processing shows a spectrum close to the one obtained by Thekaekara (1974).


Baltica ◽  
2016 ◽  
Vol 29 (1) ◽  
pp. 3-18 ◽  
Author(s):  
Marcin Kulawiak

During the blooming season, algal colonies can, in extreme cases, cover up to 200 000 square kilometres of the Baltic Sea water surface. Because the position and shape of the blooms may significantly change in a very short time due to the influence of wind and waves, regular monitoring of the blooms’ development is necessary. Currently, the desired monitoring frequency may only be achieved by means of remote sensing. The article presents a novel method of AVHRR data processing for the purpose of detection of algal blooms in the Baltic Sea. Instead of analysing the value of spectral reflectance of the algae, the algorithm analyses the frequency distribution of normalized difference in reflectance between the visible and near-infrared spectral bands. The proposed method has been implemented and tested as part of an operational Geographic Information System.


2019 ◽  
Vol 39 (1) ◽  
pp. 116-126
Author(s):  
Qian Lu ◽  
Shijie Wang ◽  
Xiaoyong Bai ◽  
Fang Liu ◽  
Shiqi Tian ◽  
...  

Geophysics ◽  
1981 ◽  
Vol 46 (3) ◽  
pp. 316-321 ◽  
Author(s):  
Graham R. Hunt ◽  
Russell C. Evarts

Visible and near‐infrared (0.35 to 2.5 μm) bidirectional reflection spectra were recorded for a suite of particulate samples from mineralogically well‐characterized serpenatinized ultramafic rocks. The reflection spectra typically exhibit well‐defined minima due to electronic and vibrational processes in the individual mineral constituents. The contrast of near‐infrared spectral features of primary magnesian silicate minerals and secondary hydrous‐serpentine group minerals can be used to indicate the degree of serpentinization of the rock, provided less than about 1 percent of finely divided magnetite is present. The effect of magnetite, apparent in rocks with more than 50 percent serpentine, is to reduce the overall reflectance and the contrast of spectral bands. Near‐infrared spectrometry is potentially a rapid and reliable technique for detecting the highly serpentinized rocks which constitute target areas for asbestos exploration.


JETP Letters ◽  
2020 ◽  
Vol 112 (1) ◽  
pp. 31-36
Author(s):  
V. I. Kukushkin ◽  
V. E. Kirpichev ◽  
E. N. Morozova ◽  
V. V. Solov’ev ◽  
Ya. V. Fedotova ◽  
...  

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