ID: 57802
Title: Effect of pH and hydraulic retention time on fermentation product distribution and subsequent treatment in microbial electrolysis cell
Author: Krishnan Vijayaraghavan, Steve Van Ginkel, Cesar I Torres, Hyung-Sool Lee, Prathap Prameswaran, Chen Zhou and Bruce E Rittmann
Editor: P K Bhattacharya
Year: 2012
Publisher: TERI - The Energy and Resource Institute, Vol 11, No 3, Septermber 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: TIDEE - TERI Information Digest on Energy and Environment
Keywords: Fermentation, Microbial electrolytic cell, Volatile fatty acid, Hydrogen
Abstract: The objectives of this study are to examine the effect of reactor pH on fermentation product distribution using anaerobic sequencing batch reactors and to evaluate the subsequent conversion of the products to H2 in an MEC. The fermentation experiments were conducted using milk as substrate at varying fermentation pH namely 4 to 7, in order to verify the volatile fatty acid distribution. The fermented liquor served as a substrate in microbial electrolysis cell.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57801
Title: Effects of acid treatment on qualities of used lubricating oil
Author: Vineet Katiyar and Sattar Husain
Editor: P K Bhattacharya
Year: 2012
Publisher: TERI - The Energy and Resource Institute, Vol 11, No 3, Septermber 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: TIDEE - TERI Information Digest on Energy and Environment
Keywords: Lubricating oil, environmental problem viscosity index
Abstract: Lubricating oil requirement is increasing day by day with the establishment of new industries, increase in number of vehicular transports, and mechanization of agriculture. The generated used oil can be considered as a source of pollution or as a resource, dependign on the methods of utilization and management. Used lubricating oil has been reclaimed by treatment with commercial sulphuric acid followed by adsorption on kieselguhr. A maximum yield 70% of reclaimed oil at acid-oil ratio of 14:100 with addition of 15% (w/v) kieselguhr has been obtained. In this paper, an attempt has been made to discuss composition of used lubricating oil and various facts about hazardous nature of used oils. This will enhance more awareness about environmental impacts of hydrocarbon industries to the science community.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57800
Title: Studies on bacterial biodegradation of Benzonitrile
Author: Ajane V H and S M Dharmadhikari
Editor: P K Bhattacharya
Year: 2012
Publisher: TERI - The Energy and Resource Institute, Vol 11, No 3, Septermber 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: TIDEE - TERI Information Digest on Energy and Environment
Keywords: Benzonitrile, Benzamide, biodegradation, benzonitrilase, bacteria
Abstract: Despite the widespread use of herbicides containing nitrile groups, comparatively little is known about the microbial metabolism of nitriles adn in particular the mechanism of cleavage of the cyanide bond by microorganisms. Soil samples were collected from different areas like agricultural land and areas surrounding pharmaceutical industries. By adaptation and acclimatization, 60 bacterial cultures were isolated. All isolates were capable of growing on mineral medium containing benzonitrile as sole source of carbon and nitrogen. Out of these 60 isolates, 17 bacterial strains were screened based on maximum production of ammonia. Secondary screening was carried out based on benzonitrile biodegradation at various pH. Three strains were selected showing maximum biodegradation in terms of ammonia production at basic, acidic, and alkaline pH, strain C8 at pH7 (7.78 ?mole), strain S14 at pH 9 (5.45 ?mole), and strain S15 at pH 4 (10.31?mole). The presence of nitrilase was confirmed qualitatively by detecting nonoccurrence of benzamide during hydrolysis. In both strains, the enzyme activity was found to be maximum in cell supernatant as compared to cell lyzate. The strain S15 was used further for optimization of growth parameters. The intact cells of S15 was showing maximum benzonitrile biodegradation at pH 4 and temperature 300C. The presence of casein as a nitrogen source and fructose as a carbon source were found to enhance the benzonitrile hydrolysis.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57799
Title: Estimating the fundamental matrix under pure translation and radial distortion0
Author: Carsten Steger
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Uncalibrated stereo, Fundamental matrix, Radial distortion, Division model, minimal solver, overdetermined solver
Abstract: Four algorithm for estimating the fundamental matrix and radial distortion for the case that the images are related by a pure cameral translation are proposed. This restricted class of motions is important in robotics and industrial applications. It is assumed that the radial distortions can be modeled by the division model. First, a linear 3-pint minimal solver is derived, which is essential to drive a RANSAC alogrithm. The minimal solver is then extended to an overdetermined linear solver, which is essential to compute starting vlaues for the third algorithms, a Gold Standard solver that returns the maximum likelihood estimate fundamental matrix and radial distortion. The three algorithms are combined into a RANSAC algorithm that determines the fundamental matrix and radial distortion automatically. An experimental evaluation determines the characteristics of the algorithms and shows the high accuracy, precision, and robustness that can be achieved. Furthermore, the evaluation shows that using algorithms that determine the fundamental matrix and radial distortion for general camera motions are not a viable alternative for the case of pure camera translations because they are significantly slower and less robust than the algorithms proposed here.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57798
Title: Conventional and fuzzy comparisons of large scale land cover products: Application to CORINE, GLC2000, MODIS and GlobCover in Europe
Author: A Perez-Hoyos, F J Garcia-Haro, J San-Miguel-Ayanz
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: GlobCover, Fuzzy comparison, LCCS, CORINE, GLC2000, MODISLC
Abstract: One of the major drawbacks of land cover products is the lack of interoperability among them. Since their development was driven by different national or international initiatives, they were developed for different purposes and hold diverse technical characteristics. Thus, comparison among products and quality monitoring is necessary in assessing their usefulness. This paper provides a methodology to compare global land cover maps that allows for differences in legend definitions among products.
Two different approaches were considered for map comparison, a Boolean approach and a new methodology based on fuzzy set theory in which the Land Cover Classification System (LCCS) acted as a general bridging system. The fuzzy approach let us reconcile legends in terms of a set of nine selected attributes. The methodology is illustrated over Europe using four different land cover products: CORINE, GLC2000, MODIS land cover (MODISLC) and GlobCover.
Overall accuracies between datasets based on a generalized nomenclature ranged from 35% (GlobCover-MODISLC) to 57% (CORINE-GLC2000). A further assessmetn based on a flexible Boolean comparison allowed us to minimize part of the uncertainty introduced by ambiguity of legends, resulting in an overall increase of agreement of around 10% in absolute terms. Reduction of positional errors produced an agreement increase of around 5%. The fuzzy approach allowed us to examine certian criteria used in classification systems to better understand the causes of discrepancies among datasets and express them in terms of relevant land attributes, irrespective of class names. This method served to highlight the consistency of the land cover maps under consideration, especially for datasets that showed higher divergences. In particular, it allows the identification of areas that are very close in land attributes, even when a Boolean comparison shows them as different.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57797
Title: Assessment of hyperspectral MIVIS sensor capability for heterogeneous landscape classification
Author: Giovanni Forzieri, Gabriele Moser, Filippo Catani
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Hyperspectral, MIVIS, classification, feature reduction, complex land covers/ uses
Abstract: The potential and limitations of the hyperspectral remote sensing MIVIS sensor (Multispectral Infrared Visible Imaging Spectrometer) in classifying heterogeneous landscapes are explored in this study. In order to quantify the discriminant information derived from selected MIVIS subsets we classified a monitored scenario by progressively invreasing the feature space dimensionality. The hyperspectral subsets are defiend through teh Sequential Forward Selection algorithm, while mapping processes have been performed through the Maximum Likelihood, Spectral Angle Mapper and Spectral Information Divergence classifiers. Impacts of spectral bands on the overall classification accuracies and single land cover-scale reliability, as well as possible dimensionality effects (Hughes phenomenon) are investigated. The analysis is tested on a 20- km stretch of the Marecchia River (Emilia Romagna, Italy) by using MIVIS data acquired in autumn 2009 and 2010 for a 17-class mapping including complex urban/rural areas. For the considered dataset, the MIVIS sensor showed an equipment failure; of the nominal 102-band MIVIs dataset, only the first 24 bands, spanning within the 0.441 - 1.319 ?m spectral range. were exploitable. Nevertheless, the available information provided valuable discriminant contributions in land cover mapping (Maximum Likelihood Overall Accuracy ~ 85%) with encouraging reliability on mixed forests, croplands, and no-vegetated floodplain patterns, whereas riparian vegetation and urban zones exhibited low classification accuracies. The relationship between the space dimensionality and the minimum training - set size that is necessary to achieve a given inter-class separability has also been experimentally investigated by progressively under-sampling the original training set. The maximum under-sampling factor that by progressively under-sampling the original training set. The maximum under-sampling factor that avoided a decrease in the overall accuracy turned out to be, at maximum, 15 for the considered data set.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57796
Title: Hyperspectral shape-based unmixing to improve intra- and interclass variability for forest and agro-ecosytem monitoring
Author: Laurent Tits, Wanda De Keersmaecker, Ben Somers, Gregory P Asner, Jamshid Farifteh, Pol Coppin
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Hyperspectral, Spectral unmixing, Shape-based metrics, agriculture, forestry, virtual reality
Abstract: The monitoring of forests and agro-ecosystems often requires the use of a spectral mixture model to provide detailed infomration on spatial and temporal variations in vegetation cover. Two key issues in the mapping of vegetation cover in complex ecosytems are the high spectral similarity (i.e. low interclass variability) between the high spectral varaibility among different vegetation species (i.e. high intravariability) as they impede the performance of the Root Mean Square Error (RMSE) criterion, traditionally used in Spectral Mixture Analysis (SMA) to optimise the fit between modelled and measured mixed signal. Shape-based objective functions have been proposed as an alternative. Experiments, based on ray-tracing simulations, indeed demonstrated the added value of implementing shape-based error metrics in unmixing of vegetation in (i) reducing the effects of intra-class endmember variability ( ?fRMSE ? 0.21 vs ?fSAM? 0.10) and (ii) highlilghting the subtle spectral differences among similar endmembers (?fRMSE ? 0.61 vs ?fSAM? 0.43). Shape -based unmixing as such as the potential to become an alterantive to the traditional but CPU intensive MESMA approach. Simulated data results presented in this study show a significant increase in fraction estimate accuracy for shape-based unmixing over MESMA (?fMESMA ? 0.15 vs ?fsSMA,SAM ? 0.10) and subsequently confirmed using three different real hyperspectral data sets.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57795
Title: Temporal characteristics of thermal satellite images for urban heat stress and heat island mapping
Author: Janet E Nichol, To Pui Hang
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Thermal, Satellite, urban , climate
Abstract: The reconstruction of urban climate is still challenging to climatologists in spite of over five decades of research including direct data measurement and model building. Methods for measuring and monitoring urban climate have strengths and weaknesses depending on the application. The mapping of patterns of urban heat stress over a city is not useful if the patterns depited apply only to the time of data acquisition. Since thermal satellite sensors can now provide detailed termperature data covering whole cities and beyond, their adoption in urban planning depnds on demonstrating their relevance to commonly prevailing conditions. This research investigates and presents a methodology based on four summertime ASTER thermal satellite images of Hong Kong for urban heat stress mapping at detailed level. It demonstrates taht satellite images obtained under certain climatic conditions, and accompanied by adequate ' in situ ' ground data, can provide a basis for an operational heat stress mapping system. The temporal limitation of thermal satellite imges is examined for both day and nightime images by comparison of image-derived air temperatures with ground data representing extended periods and other hot days and nights outside the image acquisition times. The nighttime images were found to be more representative of air temperature at other times than the daytime images, due to a more stable boundary layer, with lower wind speeds and temperature inversion at night. The nighttime images showed high and significant correlations with ground level air temperatures for an average 13-h period surrounding the image time 10.42 pm, from 6 pm to 4-8 am the next day. Additionally they were highly and significantly correlated with ground air temperature distributions on 93% of all hot summer nights in the same years. Therefore the nighttime images can be considered representative of a commonly occurring summer nighttime situation in Hong Kong, and can be used to determine the locations of areas where temperatures commonly exceed hot weather warning thresholds. Notably, the images were better able than climate stations to represent areas in the urbanized kowloon Peninsula and several smaller satellite towns which exceeded hot weather warning thresholds. Many areas exceeded the thresholds, even when no hot weather warning was in force, due to the unrepresentative location of climate stations. The images were also more able than climate stations to indicate the hottest and coolest areas over the Hong Kong territory, thereby enabling measurement of the magnitude and extent of the urban heat island.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57794
Title: Matching of straight line segments from aerial stereo images of urban areas
Author: Ali Ozgun Ok, Jan Dirk Wegner, Christian Heipke, Franz Rottensteiner, Uwe Soergel, Vedat Toprak
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Image matching, Line segment matching, Stereo images, Aerial imagery, Urban areas
Abstract: Reliable extraction of corresponding straight lines in overlapping images can be used for different purposes such as 3D object extraction, image registration, automated triangulation, etc. In this study, a new approach for the matching of straight line features from stereo aerial images is presented. Initial correspondences between stereo images are generated using a pair-wise stereo matching approach, which involves a total of seven relational constraints. The final straight line correspondences between the stereo images are established in a line-to-line matching stage. the optimal settings for the parameters guiding the matching phase are determined after analysing the probability density functions (PDFs). The proposed approach is tested on 30 image patches of two different urban areas, and as a result, very successful and promising stereo line matching performances are achieved. Besides, the comparison of the results of teh proposed approach with the results of one of the state-of-the-art stereo matching approaches proves the superiority and potential of the proposed approach.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57793
Title: Combined rigorous-generic direct orthorectification procedure for IRS-p6 sensors
Author: Meisam Yousefzadeh, Barat Mojaradi
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Direct georeferencing, Orthoimage, Pushbroom, Ancillary data, DEM, Google Earth
Abstract: The accessibility of global data, such as the digital elevation model (DEM), and the development of global visualisations allow promising new methods for minimising the distortion in the online generation of rough orthorectified products to be developed. Direct georeferencing (DG) has attracted a considerable amount of attention in the applications of pushbrrom raw images in orthorectification or mono-plotting using ancillary satellite data. This study builds on recent DG Studies to achieve an "orthoimage" from raw data and to determine potential mapping errors due to the DG procedure. Thus, this paper focuses on establishing a simple method for mitigating the misalignments of space -borne imageries to be used in direct orthorectification. Towards this goal, instead fo image resectioning, affine transformation in different coordinate systems is employed in the orthorectification algorithm to compensate for the systematic DG errors. For a given point, the elevation corresponding to the obtained planimetric coordinate is extracted using available topographic maps and global DEMs, such as SRTM ' s and ASTER ' s DEMs. As a result, parameters no longer need to be updated, as in the conventional orthophoto generation methods. To evaluate the proposed procedures, experiments were conducted over three different IRS-p6 sensors in five datasets with different swath widths and tilt angles. The obtained results also demonstrate that the geographic coordinate system and a simple 2D affine transformation can efficiently correct misalignments.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57792
Title: LiDAR-Landsat data fusion for large-area assessment of urban land cover: Balancing spatial resolution, data volume and mapping accuracy
Author: Kunwar K Singh, John B Vogler, Douglas A Shoemaker, Ross K Meentemeyer
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: LiDAR, Landsat, Fusion, land cover, large-area assessment, mapping accuracy, managed clearings
Abstract: The structural characteristics of Light Detection and Ranging (LiDAR) data are increasingly used to classify urban environments at fine scales, but have been underutilized for distinguishing heterogeneous land covers over large urban regions due to high cost, limited spectral information, and the computations difficulties posed by inherently large data volumes. Here we explore tradeoffs between potential gains in mapping accuracy with computational costs by integrating structural and intensity surface models extracted from LiDAR data with Landsat Thematic Mapper (TM) imagery and evaluating the degree to which TM, LiDAR, and LiDAR-TM fusion dat discriminated land covers in the rapidly urbanizing region of Charlotte, North Carolina, USA. Using supervised maximum likelihood (ML) and classification tree (CT) methods, we classified TM data at 30 m adn LiDAR data and LiDAR-TM fusions at 1m, 5 m, 10 m, 15 m and 30 m resolutions. We assessed the relative contributions of LiDAR structural and intensity surface models to classification map accuracy and identified optimal spatial resolution of LiDAR surface models for large-area assessments of urban land cover. ML classification of 1m LiDAR-TM fusions using both structural and intensity surface models increased total accuracy by 32% compared to LiDAR alone and by 8% over TM at 30 m. Fusion data using all LiDAR surface models improved class discrimination of spectrally similar forest, farmland, and managed clearings and produced the heighest total accuracies at 1 m, 5m, and 10 m resolutions (87.2%, 86.3% and 85.4%, respectively). At all resolutions of fusion data and using either ML or CT classifier, the relative contribution of the LiDAR structural surface models (canopy height and normalized digital surface model) to classification accuracy is greater than the intensity surface. Our evaluation of tradeoffs between data volume and thematic map accuracy for this study system suggests that a spatial resolution of 5 m for LiDAR surface models best balances classification performance and the computational challenges posed by large-area assessments of land cover.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57791
Title: Range camera self-calibration with scattering compensation
Author: Derek D Lichti, Xiaojuan Qi, Tanvir Ahmed
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Range camera, Geometric self-calibration, error modelling, scattering compensation
Abstract: Time-of-flight range camera data are prone to the scattering bias caused by multiple internal reflections of light received from a highly reflective object in the camera ' s foreground that induce a phase shift in the light received from background targets. The corresponding range bias can have serious implications on the quality of data of captured scenes as well as the geometric self-calibration of range cameras. In order to minimise the impact of the scattering range biases, the calibration must be performed over a planar target field rather than a more desirable 3D target field. This significantly impacts the quality of the rangefinder offset parameter estimation due to its high correlation with the camera perspective centre position. In this contribution a new model to compensate for scattering-indcued range errors is proposed that allows range camera self-calibration to be conducted over a 3D target field. Developed from experimental observations of scattering behaviour under specific scene conditions, it comprises four new additional parameters that are estimated in the self-calibrating bundle adjustment. The results of experiments conducted on five range camera datasets demonstrate the model ' s efficacy in compensating for the scattering error without compromising model fidelity. It is further demonstrated that it actually reduces the rangefinder offset-perspective centre correlation and its use with a 3D target field is the preferred method for calibration narrow field-of-view range cameras.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57790
Title: Automated planimetric quality control in high accuracy airborne laser scanning surveys
Author: George Vosselman
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Laser scanning, Mapping, quality analysis, point cloud, feature extraction
Abstract: With the increasing point densities of airborne laser scanning surveys, the applications of the generated point clouds have evolved from the production of digital terrain models to 3D modelling of a wide variety of objects. Likewise in quality control procedures criteria for height accuracy are extended with measures to describe the planimetric accuracy. This paper introduces a measure for the potential accuracy of outlining objects in a point cloud. It describes how this accuracy can be varified with the use of ridge lines of gable roofs in strip overlaps. Because of the high accuracy of modern laser scanning surveys, the influence of roof tiles onto the estimation of ridge lines is explicitly modelled. New selection criteria are introduced that allow an automated, reliable and accurate extractin of ridge lines from point clouds. The applicability of the procedure is demonstrated in a pilot project in an area covering 100, 000 ha with around 20 billion points.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57789
Title: A simple method to recover the latency time of tactical grade IMU systems
Author: Nicolas Seube, Alan Picard, Mathieu Rondeau
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: LiDAR, Inertial measurement unit, Time-tagging, Latency, Calibration
Abstract: This paper investigates the problem of latency estimation between an IMU (Inertial Measurement Unit) and a LiDAR (Light Detection And Ranging). The latency is due to the IMU itself, but also to the acquisition software and hardware configuration, which is generally set-up by survey systems users. We propose a method for latency estimation, and we show that this method meets the accuracy requirements of most LiDAR survey applications. We present test results of our method on various acquistion systems and hardware configuration which demonstrate that it is able to identify very accurately the total IMU-LiDAR latency through a simple procedure. The principle of the method is to put the LiDAR-IMU in rotational motions, thanks to a rotating table. By scanning a spherical target at different angular velocities, we can observe position shifts of the targets center from which we derive an estimate the IMU-LiDAR latency. The method we propose works without absolute positioning and is therefore not sensitive to nonmodeled errors coming from GPS geolocated data. We show that in estimating accurately the LiDAr-IMU latency, we can optimize the configuration of a mobile LiDAR survey system in order ot enhance its robustness with respect to high motion dynamics of the survey platform.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None
ID: 57788
Title: Forest variable estimation using a high-resolution digital surface model
Author: J Jarnstedt, A Pekkarinen, S Tuominen, C Ginzler, M Holopainen, R Viitala
Editor: George Vosselman
Year: 2012
Publisher: Elsevier, Vol 74, November 2012
Source: Centre for Ecological Sciences
Reference: None
Subject: ISPRS Journal of Photogrammetry and Remote Sensing
Keywords: Photogrammetric surface model, canopy height model, Airborne laser scanning, forest inventory
Abstract: Airborne laser scanning is today considered the most accurate remote sensing method for forest inventory. The main advantage of laser scanning is the three-dimensional data. Three-dimensional canopy surface models can also be derived by means of digital aerial photogrammetry on the basis of optical remote sensing imagery. The photogrammetric surface models require high-resolution aerial images with stereo coverage. In this study, both a canopy height model derived from a photogrammetric digital surface model adn laser point data were tested in estimation of sample-plot-level forest attributes. The attributes tested include diameter, mean and dominant height, basal area, and volume of growing stock. The results indicate that the laser data give higher accuracy for the estimated forest variables than does the photogrammetric canopy height model. The stand dominant height was the most accurately estimated variable from both data sources and showed the smallest difference between the laser data and photogrammetric canopy height models. The performance of the photogrammetric model was poorest in estimation of basal area and volume of growing stock.
Location: TE 12, Biologicalsciences Building, IISc
Literature cited 1: None
Literature cited 2: None