TY - CPAPER
ID - apan2003
AU - Apan, Armando
AU - Held, Alex
AU - Phinn, Stuart
AU - Markley, John
TI - Formulation and assessment of narrow-band vegetation indices from EO-1 hyperion imagery for discriminating sugarcane disease
UR - http://eprints.usq.edu.au/8061/
PR - Spatial Sciences Institute
T2 - 2003 Spatial Sciences Institute Conference: Spatial Knowledge Without Boundaries (SSC2003)
CY - Canberra, Australia
PY - 2003
SP - 1-13
N1 - No evidence of copyright restrictions.
AB - The increasing commercial availability of hyperspectral image data promotes growing interests in the development of application-specific narrow-band spectral vegetation indices (SVIs). However, the selection of the optimum SVIs for a particular purpose is not straightforward, due to the wide choice of band combinations and transformations, combined with specific application purposes and conditions. Thus, the aim of this study was to develop an approach for formulating and assessing narrow-band vegetation indices, particularly those from EO-1 Hyperion imagery. The focus of SVI development was for discriminating sugarcane areas affected by 'orange rust' (Puccinia kuehnii) disease in Mackay, Queensland, Australia. After a series of pre-processing and post-atmospheric correction techniques, an empirical-statistical approach to SVI development was designed and implemented. This included the following components: a) selection of sample pixels of diseased and nondiseased areas, b) visual examination of spectral plots to identify bands of maximum spectral separability, c)generation of SVIs, d) use of multiple discriminant function analysis, and e) result interpretation and validation. From the forty existing and newly developed vegetation indices, the output discriminant function (i.e. a linear combination of three indices) attained a classification accuracy of 96.9% for the hold-out sample pixels. The statistical analyses also produced a list of function coefficients and correlation rankings that indicate the predictive potential of each SVI. The newly formulated 'Disease-Water Stress Indices' (DSWI) produced the highest correlations. The approach designed for this study provided a systematic framework in the formulation and assessment of SVIs for sugarcane disease detection.
KW - hyperspectral remote sensing, spectral vegetation indices, sugarcane disease, Hyperion
ER -
TY - JOUR
ID - aparicio2004
AU - Aparicio, N.
AU - Villegas, D.
AU - Royo, C.
AU - Casadesus, J.
AU - Araus, J. L.
TI - Effect of sensor view angle on the assessment of agronomic traits by ground level hyper-spectral reflectance measurements in durum wheat under contrasting Mediterranean conditions
UR - http://dx.doi.org/10.1080/0143116031000116967
DO - 10.1080/0143116031000116967
T2 - International Journal of Remote Sensing
PY - 2004
DA - 2004/03/01
SN - 0143-1161
VL - 25
IS - 6
SP - 1131-1152
AB - The objective of this work is to study the effect of changing the sensor view angle on spectral reflectance indices and their relationships with yield and other agronomic traits. Canopy reflectance spectra of 25 durum wheat genotypes were measured with a field spectroradiometer at two view angles, nadir and 30°, from anthesis to maturity in two years and two water regimes. Nine spectral reflectance indices were calculated from reflectance measurements for correlation with yield and several agronomic traits. At off-nadir position more reflected radiation was collected, associated with the reflective characteristics of stems. The performance of the indices predicting the yield and the agronomic traits varied as a function of sensor view angle, and were moreover affected by leaf area index (LAI) value. At high LAI, simple ratio (SR) and normalized difference vegetation index (NDVI), calculated at off-nadir position, were better predictors of traits related to the density of stems and poorer predictors of traits related to green area. On the other hand, at low LAI the indices normalized pigment chlorophyll index (NPCI) and water index (WI) were better predictors of yield and all the other traits when the sensor view angle was at nadir, whereas no differences due to sensor angle were accounted for the other three indices. The different performance of indices at low and high LAI is discussed.
ER -
TY - JOUR
ID - ceccato2002
AU - Ceccato, Pietro
AU - Gobron, Nadine
AU - Flasse, Stéphane
AU - Pinty, Bernard
AU - Tarantola, Stefano
TI - Designing a spectral index to estimate vegetation water content from remote sensing data: Part 1: Theoretical approach
UR - http://www.sciencedirect.com/science/article/pii/S0034425702000378
DO - 10.1016/s0034-4257(02)00037-8
T2 - Remote Sensing of Environment
PY - 2002
SN - 0034-4257
VL - 82
IS - 2â3
SP - 188-197
AB - This paper describes the methodology used to create a spectral index to retrieve vegetation water content from remotely sensed data in the solar spectrum domain. A global sensitivity analysis (GSA) using radiative transfer models is used to understand and quantify vegetation water content effects on the signal measured at three levels: leaf, canopy, and atmosphere. An index is then created that optimises retrieval of vegetation water content (in terms of water quantity per unit area at canopy level) and minimises perturbing effects of geophysical and atmospheric effects. The new index, optimised for the new SPOT-VEGETATION sensor, is presented as an example. Limitations and robustness of the index are also discussed.
ER -
TY - JOUR
ID - datt1999
AU - Datt, Bisun
TI - Remote Sensing of Water Content in Eucalyptus Leaves
DO - http://dx.doi.org/10.1071/BT98042
T2 - Australian Journal of Botany
PY - 1999
VL - 47
IS - 6
SP - 909-923
AB - The spectral reflectance of leaves from several Eucalyptus species was measured over the 400â2500 nm wavelengths with a laboratory spectroradiometer. The relationship of reflectance with the gravimetric water content and equivalent water thickness (EWT) of the leaves was analysed. The results showed that EWT was strongly correlated with reflectance in several wavelength regions. No significant correlations could be obtained between reflectance and gravimetric water content. It was also possible to confirm theoretically that reflectance changes of leaves could be directly linked to changes in EWT but not to changes in gravimetric water content. Several existing reflectance indices were evaluated for estimation of leaf water content and some new indices were developed and tested. Two semi-empirical indices developed in this study, (R850 - R2218)/(R850 - R1928) and (R850 - R1788)/(R850 - R1928), were found to show significantly stronger correlations with EWT than all other indices tested. It was also shown that these new indices were least sensitive to the effects of radiation scatter. The indices (R850 - R2218)/(R850 - R1928) and (R850 - R1788)/(R850 - R1928) are therefore proposed as two new indices for the remote estimation of vegetation water content.
ER -
TY - JOUR
ID - penuelas1993
AU - Penuelas, J.
AU - Filella, I.
AU - Biel, C.
AU - Serrano, L.
AU - Save, R.
TI - The reflectance at the 950â970 nm region as an indicator of plant water status
UR - http://dx.doi.org/10.1080/01431169308954010
DO - 10.1080/01431169308954010
PR - Taylor & Francis
T2 - International Journal of Remote Sensing
PY - 1993
SN - 0143-1161
VL - 14
IS - 10
SP - 1887-1905
AB - We present new remote sensing indices of plant water status: the ratio between the reflectance at 970 nm, one of the water absorption bands, and the reflectance at a reference wavelength, 900 nm (R970/R9000; the first derivative minimum in this near-infrared region (dNIRminimum ) and the wavelength where this minimum is found ( ?NIRminimum). In order to evaluate them, we carried out three experiments. Daily irrigated gerbera plants were allowed to dry until almost wilting and then daily irrigation was restarted; pepper and bean plants were grown for four months submitted to two different irrigation treatments; and bean detached leaves were submitted to progressive dehydration whereas pressure-volume curves were being carried out. In gerbera plants, the trough about 950?970 nm decreased as the drought was increasing. Therefore, the R970/R900 index and the dNIRminimum closely tracked the changes in relative water content (RWC), leaf water potential, stomatal conductance and the foliage-air temperature differences. The ?dNIRminimum tracked even better these changes in gerberas. However, these water status indices began to be significant when the water stress was already well developed, at RWC smaller than 85 per cent. The same happened to detached leaves of beans which did not present differences above ?1·55 MPa water potential. Beans and peppers growing at soil matric potentials larger than ?0·04 MPa presented higher R970/R900 values than those growing at soil matric potentials only larger than ?0·01 MPa. In all the cases, the maximum response of these indices was found in the varieties or the species that lost cell wall elasticity in response to drought stress. This could indicate an important structural component in these indices changes. Relative water content itself seemed to be, however, the most important factor as shown by the highest correlation coefficients with these spectral indices. These spectral signals were more evident at canopy level than at leaf level. They seem to be useful as water status indicators at ground level, especially when there are not important changes of LAI and when plants wholly cover the soil.
ER -
TY - JOUR
ID - penuelas1997
AU - Penuelas, J.
AU - Pinol, J.
AU - Ogaya, R.
AU - Filella, I.
TI - Estimation of plant water concentration by the reflectance Water Index WI (R900/R970)
UR - http://dx.doi.org/10.1080/014311697217396
DO - 10.1080/014311697217396
T2 - International Journal of Remote Sensing
PY - 1997
DA - 1997/09/01
SN - 0143-1161
VL - 18
IS - 13
SP - 2869-2875
AB - Abstract Water Index WI (R900/R970) was used for the estimation of plant water concentration (PWC) by ground-based, reflectance measurements. Reflectance and PWC were measured for adult plants growing in the field throughout an annual cycle and in potted seedlings submitted to progressive desiccation. The species studied were characteristicly Mediterranean: Pinus halepensis, Quercus ilex, Quercus coccifera, Arbutus unedo, Cistus albidus, Cistus monspeliensis, Phillyrea angustifolia, Pistacia lentiscus and Brachypodium retusum . WI was significantly correlated with PWC when all the species were considered together, and with almost all the species considered individually, especially when a wider range of PWC was obtained by extreme dessication of experimental plants. The correlations increased when normalizing WI by NDVI. The wavelength of the trough corresponding to water absorption band tended to shift from 970-980 nm to lower wavelengths 930-950 nm with decreasing PWCs. Infrared measurement of plant temperature and T leaf - T air provided worse assessment of PWC. A simple radiometer measuring plant reflectance at 680, 900, and 970nm could speed up the measurement of PWC, and be useful in wildfire risk evaluation and drought assessment.
ER -
TY - JOUR
ID - pe_uelas1998
AU - Peñuelas, J.
AU - Filella, I.
TI - Visible and near-infrared reflectance techniques for diagnosing plant physiological status
UR - http://dx.doi.org/10.1016/S1360-1385(98)01213-8
DO - 10.1016/S1360-1385(98)01213-8
T2 - Trends in Plant Science
PY - 1998
SN - 13601385
VL - 3
IS - 4
SP - 151-156
ER -
TY - JOUR
ID - pinter2003
AU - Pinter, P. J.
AU - Hatfield, J. L.
AU - Schepers, J. S.
AU - Barnes, E. M.
AU - Moran, M. S.
AU - Daughtry, C. S. T.
AU - Upchurch, D. R.
TI - Remote sensing for crop management
UR - ://WOS:000221193400006
T2 - Photogrammetric Engineering and Remote Sensing
PY - 2003
DA - Jun
SN - 0099-1112
VL - 69
IS - 6
SP - 647-664
N1 - ISI Document Delivery No.: 817RA
Times Cited: 88
Cited Reference Count: 256
Pinter, PJ Hatfield, JL Schepers, JS Barnes, EM Moran, MS Daughtry, CST Upchurch, DR
Amer soc photogrammetry
Bethesda
AB - Scientists with the Agricultural Research Service (ARS) and various government agencies and private institutions have provided a great deal of fundamental information relating spectral reflectance and thermal emittance properties of soils and crops to their agronomic and biophysical characteristics. This knowledge has facilitated the development and use of various remote sensing methods for non-destructive monitoring of plant growth and development and for the detection of many environmental stresses which limit plant productivity. Coupled with rapid advances in computing and position-locating technologies, remote sensing from ground-, air-, and space-based platforms is now capable of providing detailed spatial and temporal information on plant response to their local environment that is needed for site specific agricultural management approaches. This manuscript, which emphasizes contributions by ARS researchers, reviews the biophysical basis of remote sensing; examines approaches that have been developed, refined, and tested for management of water, nutrients, and pests in agricultural crops; and assesses the role of remote sensing in yield prediction. It concludes with a discussion of challenges facing remote sensing in the future.
KW - water-stress index
KW - spectral-biophysical data
KW - soil heat-flux
KW - infrared
KW - aerial photography
KW - laser-induced fluorescence
KW - constant leaf
KW - temperature
KW - adjusted vegetation index
KW - surface-energy balance
KW - clover-seed production
KW - gossypium-hirsutum l
ER -
TY - JOUR
ID - pu2008
AU - Pu, Ruiliang
AU - Gong, Peng
AU - Yu, Qian
TI - Comparative Analysis of EO-1 ALI and Hyperion, and Landsat ETM+ Data for Mapping Forest Crown Closure and Leaf Area Index
UR - http://www.mdpi.com/1424-8220/8/6/3744/
T2 - Sensors
PY - 2008
SN - 1424-8220
VL - 8
IS - 6
SP - 3744-3766
ER -
TY - JOUR
ID - royo2003
AU - Royo, C.
AU - Aparicio, N.
AU - Villegas, D.
AU - Casadesus, J.
AU - Monneveux, P.
AU - Araus, J. L.
TI - Usefulness of spectral reflectance indices as durum wheat yield predictors under contrasting Mediterranean conditions
UR - http://dx.doi.org/10.1080/0143116031000150059
DO - 10.1080/0143116031000150059
T2 - International Journal of Remote Sensing
PY - 2003
DA - 2003/01/01
SN - 0143-1161
VL - 24
IS - 22
SP - 4403-4419
ER -
TY - JOUR
ID - strachan2002
AU - Strachan, Ian B.
AU - Pattey, Elizabeth
AU - Boisvert, Johanne B.
TI - Impact of nitrogen and environmental conditions on corn as detected by hyperspectral reflectance
DO - 10.1016/s0034-4257(01)00299-1
T2 - Remote Sensing of Environment
PY - 2002
SN - 0034-4257
VL - 80
IS - 2
SP - 213-224
AB - Indices derived from hyperspectral reflectance spectra have the potential to be used as indicators of environmental stress in crops. This study uses canopy-scale, ground-based measurements of hyperspectral reflectance to demonstrate the temporal patterns in corn development under imposed fertility (N rate) and environmental (water availability) stresses. In 1998, two large areas in a 30-ha corn (Zea mays, L.) field near Ottawa, Canada (45°18′N, 75°44′W) were supplied with 99 and 17 kg N ha−1, while the balance of the field received the recommended rate of 155 kg N ha−1. Reflectance measurements were taken nine times using a portable spectroradiometer at georeferenced locations within these areas. Individual reflectance-based indices demonstrated the relative differences between application rates and identified both nitrogen and water stresses at various times in the growing season. No single index was able to describe the status of the corn crop throughout the season. Canonical discriminant analysis provided accurate classification of samples by N rate during early, mid, and late season conditions with overall success rates of 70%, 88%, and 93%, respectively. A shift in importance from green-based derivatives to red-based derivatives was noted from mid to late season and attributed to the natural reduction in green pigments as the crop entered senescence. Canopy-scale photochemical reflectance index (PRI) was shown to be correlated with canopy radiation use efficiency (RUE). Mid-season water stress affected the relationship. Multiple years of data are required to demonstrate robust relationships between hyperspectral indices and corn ecophysiological status because of the interaction between environmental and nutrient stresses. Identifying areas of fields sensitive to weather-induced stresses will allow better management of N application. Timing the collection of hyperspectral image data at early and late vegetative phase could enhance precision agriculture by allowing supplemental nutrient application, identifying stress patterns and aid in yield forecasting.
KW - Hyperspectral reflectance
KW - Precision agriculture
KW - Stress detection
KW - Corn field
KW - Radiation use efficiency
KW - Chlorophyll
KW - Leaf area index
KW - Crop water content
ER -
TY - JOUR
ID - underwood2003
AU - Underwood, Emma
AU - Ustin, Susan
AU - DiPietro, Deanne
TI - Mapping nonnative plants using hyperspectral imagery
UR - http://www.sciencedirect.com/science/article/pii/S0034425703000968
DO - 10.1016/s0034-4257(03)00096-8
T2 - Remote Sensing of Environment
PY - 2003
SN - 0034-4257
VL - 86
IS - 2
SP - 150-161
AB - Nonnative plant species are causing enormous ecological and environmental impacts from local to global scale. Remote sensing images have had mixed success in providing spatial information on land cover characteristics to land managers that increase effective management of invasions into native habitats. However, there has been limited evaluation of the use of hyperspectral data and processing techniques for mapping specific invasive species based on their spectral characteristics. This research evaluated three different methods of processing hyperspectral imagery: minimum noise fraction (MNF), continuum removal, and band ratio indices for mapping iceplant (Carpobrotus edulis) and jubata grass (Cortaderia jubata) in California's coastal habitat. Validation with field sampling data showed high mapping accuracies for all methods for identifying presence or absence of iceplant (97%), with the MNF procedure producing the highest accuracy (55%) when the classes were divided into four different densities of iceplant.
KW - AVIRIS
KW - Hyperspectral
KW - Invasive plants
KW - Nonnative plants
KW - Iceplant
KW - Carpobrotus edulis
KW - Jubata grass
KW - Cortaderia jubata
KW - Mapping
ER -
TY - JOUR
ID - zarco-tejada_p_j_sepulcre-cant_2007
AU - Zarco-Tejada P.J.
AU - Sepulcre-Cantó, G.
TI - REMOTE SENSING OF VEGETATION BIOPHYSICAL PARAMETERS FOR DETECTING STRESS CONDITION AND LAND COVER CHANGES
T2 - Estudios de la Zona No Saturada del Suelo
PY - 2007
VL - 8
ER -
TY - ELEC
ID - idb
AU - Henrich, V.
AU - Krauss, G.
AU - Götze, C.
AU - Sandow, C.
TI - The IndexDatabase
UR - https://www.indexdatabase.de/
CY - Bonn
PY - 2011
DA - 2011
ER -