CANOPY HEIGHT MODELS TO MONITOR AREAS UNDER DEGRADATION IN MIXED OMBROPHILE

ABSTRACT This research was aimed at providing a study of digital elevation models from Airborne Laser Scanner (ALS) data. The goal was to improve the forest monitoring, or more specifically, arboreal canopy monitoring, which contains the most elevated vegetation of the forest. It is also described as the surface above the canopy top. The region of rain forest between the states of São Paulo and Paraná in Brazil was analyzed. The proposed method employs the ALS system that provides information related to different vegetative cover bedding, to analyze it and reach to estimate for the most elevated stage. The methodology is based on differentiating the identified surfaces in the original set of data. It uses these surfaces with a raster, which was obtained from an interpolation of different sets of points from the surfaces of interest. The raster structure, unlike vector data, allows for processes linked to the digital processing of images. It enables implementation of digital filters over the data. The method helped in reducing the influence of errors during classification and achieving the theoretical surface. The results revealed a coherent relationship with anthropogenic influence such as the introduction of exotic vegetation. We concluded that arboreal vegetation could be an index of conservation for environmental registration and licensing organizations.

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A glacier inventory for South Tyrol, Italy, based on airborne laser-scanner data

Annals of Glaciology ◽

10.3189/172756410790595903 ◽

2009 ◽

Vol 50 (53) ◽

pp. 46-52 ◽

Cited By ~ 49

Author(s):

Christoph Knoll ◽

Hanns Kerschner

Keyword(s):

Laser Scanner ◽

Glacier Area ◽

Scanner Data ◽

Equilibrium Line Altitude ◽

Glacier Inventory ◽

New Approach ◽

Airborne Laser Scanner ◽

South Tyrol ◽

Airborne Laser ◽

Digital Elevation

AbstractA new approach to glacier inventory, based on airborne laser-scanner data, has been applied to South Tyrol, Italy: it yields highly accurate results with a minimum of human supervision. Earlier inventories, from 1983 and 1997, are used to compare changes in area, volume and equilibrium-line altitude. A reduction of 32% was observed in glacier area from 1983 to 2006. Volume change, derived from the 1997 and 2006 digital elevation models, was –1.037 km3, and an ELA rise of 54 m, to almost 3000 m a.s.l., was calculated for this period. Losses vary widely for individual glaciers, but have accelerated for all South Tyrolean glaciers since the first inventory in 1983.

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Airborne Laser Scanner: principles of operation, recent uses in Brazil and regulatory issue from laws and parameters in Brazil and in the USA

Journal of Hyperspectral Remote Sensing ◽

10.29150/jhrs.v6.7.p338-353 ◽

2016 ◽

Vol 6 (7) ◽

pp. 338

Author(s):

Carlos Henrique Sopchaki ◽

Tony Vinicius Moreira Sampaio

Keyword(s):

Digital Elevation Model ◽

Spatial Resolution ◽

Laser Scanner ◽

Airborne Laser Scanner ◽

Regulatory Issue ◽

Regulatory Documents ◽

Airborne Laser ◽

Digital Elevation ◽

The Usa ◽

Elevation Model

DEM generated from LIDAR are being increasingly used in various fields of science. Thus, this article presents a review of the operation of the LIDAR and makes a survey of some recent research using that product in Brazil in order to identify methodologies for assigning spatial resolution of the survey and also the DEM. Also has been approached issue of standards and legislation for assigning spatial resolution both for the survey conducted via Airborne Laser Scanner, as for the Digital Elevation Model generated from the survey. The results showed that in Brazil, there is no standardized procedure with regard to the allocation of spatial resolution and is no shortage of laws and norms that regulate the activity in the country, unlike other countries with several regulatory documents in this area.

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UNCERTAINTY IN LANDSLIDES VOLUME ESTIMATION USING DEMs GENERATED BY AIRBORNE LASER SCANNER AND PHOTOGRAMMETRY DATA

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-3-w4-397-2018 ◽

2018 ◽

Vol XLII-3/W4 ◽

pp. 397-404 ◽

Cited By ~ 3

Author(s):

C. Parente ◽

M. Pepe

Keyword(s):

Remote Sensing ◽

Laser Scanner ◽

Volume Estimation ◽

Engineering Project ◽

Airborne Laser Scanner ◽

Airborne Laser ◽

Digital Elevation ◽

Volumetric Accuracy ◽

Elevation Model

<p><strong>Abstract.</strong> The purpose of this paper is to identify an approach able to estimate the uncertainty related to the measure of terrain volume generated after a landslide. The survey of the area interested of landslide can be performed by Photogrammetry &amp; Remote Sensing (PaRS) techniques. Indeed, depending on the method and technology used for the survey, a different level of accuracy is achievable. The estimate of the quantity of the terrain implicated in the landslide influences the type of geological and geotechnical approach, the civil engineering project on the area and of consequence, the costs to sustain for a community. According to the experiences and recommendations reported in the ASPRS guidelines, an example of the approach used to estimate volumetric accuracy concerning one of the most important landslide in Europe is shown in this paper. In this case study, the dataset is constituted by a Digital Elevation Model (DEM) obtained by photogrammetric (stereo-images) method (pre-landslide) and another by Airborne Laser Scanner (after-landslide). By the comparisons of Airborne Laser Scanner (ALS) and photogrammetry DEMs obtained from successive surveys, it has been possible to produce maps of differences and of consequence, to calculate the volume of the terrain (eroded or accumulated). In order to calculate the uncertainty of volume, a procedure that takes in account even the different accuracy achievable in the vegetation area is explained and discussed.</p>

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Estimation of Vegetation-Induced Flow Resistance for Hydraulic Computations Using Airborne Laser Scanning Data

Water ◽

10.3390/w13131864 ◽

2021 ◽

Vol 13 (13) ◽

pp. 1864

Author(s):

Peter Mewis

Keyword(s):

Laser Scanning ◽

Flow Resistance ◽

Laser Scanner ◽

Airborne Laser Scanning ◽

Density Parameter ◽

Vegetation Density ◽

Airborne Laser Scanner ◽

Airborne Laser ◽

Bed Roughness ◽

Available Information

The effect of vegetation in hydraulic computations can be significant. This effect is important for flood computations. Today, the necessary terrain information for flood computations is obtained by airborne laser scanning techniques. The quality and density of the airborne laser scanning information allows for more extensive use of these data in flow computations. In this paper, known methods are improved and combined into a new simple and objective procedure to estimate the hydraulic resistance of vegetation on the flow in the field. State-of-the-art airborne laser scanner information is explored to estimate the vegetation density. The laser scanning information provides the base for the calculation of the vegetation density parameter ωp using the Beer–Lambert law. In a second step, the vegetation density is employed in a flow model to appropriately account for vegetation resistance. The use of this vegetation parameter is superior to the common method of accounting for the vegetation resistance in the bed resistance parameter for bed roughness. The proposed procedure utilizes newly available information and is demonstrated in an example. The obtained values fit very well with the values obtained in the literature. Moreover, the obtained information is very detailed. In the results, the effect of vegetation is estimated objectively without the assignment of typical values. Moreover, a more structured flow field is computed with the flood around denser vegetation, such as groups of bushes. A further thorough study based on observed flow resistance is needed.

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