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Pubblicazioni Scientifiche
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Pubblicazioni per anno
Application of k-nearest neighbor on multispectral images to estimate forest parameters; Aplicação de k-nearest neighbor em imagens multispectrais para a estimativa de parâmetros florestais
Giongo
,
Marcos Vinicius
,
Chiavetta
,
U.
,
Soares Koehler
,
Henrique Soares
,
Machado
,
S. A.
,
Kirchner
,
Flávio Felipe
Mostra abstract
Natural resources management requires several parameters estimate in order to support the identification of the best alternatives to forest areas management. In particular, forest ecosystems require a complex and increasing set of descriptive information, where forest inventories put up important information, however not in a continuous spatial way. Lately, several scientific researches have been focusing on establishing methodologies to relate data from field to those obtained from multispectral images. Modeling these relations can extend the estimates of forest inventory data to not sampled areas. This research evaluated performance of non-parametric analysis using the K-Nearest Neighbor (k-NN) on SPOT 5 images. It evaluated the results obtained from the spatialization of some forest attributes in a forest area located at Molise, Italy. Among several methodologies for spatial distance calculations, the use of multiregressive non-parametric distances revealed the best results. Density and number of species on the ground revealed a Pearson correlation coefficient of = 0.58 as compared to data obtained from multispectral images, lightly lower than the obtained for basal area and volume, which were = 0.62 and 0.71, respectively.
Assessment of potential bioenergy from coppice forests trough the integration of remote sensing and field surveys
Lasserre
,
Bruno
,
Chirici
,
Gherardo
,
Chiavetta
,
U.
,
Garfì
,
Vittorio
,
Tognetti
,
Roberto
,
Drigo
,
Rudi
,
Di Martino
,
P.
,
Marchetti
,
Marco
remote sensing
forest inventory
sustainable forest management
coppice
firewood biomass
k-nearest neighbours
Mostra abstract
A spatially explicit knowledge of forest resources is essential to support the sustainable use of wood as a fuel for producing energy (firewood).This paper describes the integrated use of remotely sensed data and sample based forest inventories to derive a biomass map for coppice forest, resulted estimated potential biomass available is contrasted with local domestic consumptions at the municipality level. The test was carried out in an environmentally and socially homogeneous district of Apennine Mountains (Alto Molise, south-central Italy) coupling multispectral high resolution Landsat 7 ETM+ satellite imagery and a local forest inventory trough the application of the non-parametric estimation procedure k-Nearest Neighbours (k-NN). Several forest management scenarios were applied in order to evaluate their impact on the potential availability of firewood from coppice forests.The paper introduces data and methods used and presents the achieved results both in terms of the accuracy of the biomass map produced by k-NN and of the relationship between the potential availability and demand for firewood.These results demonstrated that k-NN is able to estimate the biomass of coppice forest in the test area with an accuracy level comparable with recent similar application of k-NN carried out in Boreal regions (RMSE of 25.6%).The application of different forest management scenarios have a significant impact on local estimated firewood balance between potential supply from coppice forests and demand for domestic consumption, depending of the scenarios the net balance changed up to 84%. © 2010 Elsevier Ltd.