Remote sensing for resources development and environmental management: Remote sensing for resources development and environmental management

Damen, M. C. J.

Bibliographic data

Multivolume work

Persistent identifier:: 856342815

Title:: Remote sensing for resources development and environmental management

Sub title:: proceedings of the 7th international Symposium, Enschede, 25 - 29 August 1986

Year of publication:: 1986

Place of publication:: Rotterdam; Boston

Publisher of the original:: A. A. Balkema

Identifier (digital):: 856342815

Language:: English

Additional Notes:: Volume 1-3 erschienen von 1986-1988

Editor:: Damen, M. C. J.

Document type:: Multivolume work

Volume

Persistent identifier:: 856343064

Title:: Remote sensing for resources development and environmental management

Sub title:: proceedings of the 7th international Symposium, Enschede, 25 - 29 August 1986

Scope:: XV, 547 Seiten

Year of publication:: 1986

Place of publication:: Rotterdam; Boston

Publisher of the original:: A. A. Balkema

Identifier (digital):: 856343064

Illustration:: Illustrationen, Diagramme

Signature of the source:: ZS 312(26,7,1)

Language:: English

Usage licence:: Attribution 4.0 International (CC BY 4.0)

Editor:: Damen, M. C. J.

Publisher of the digital copy:: Technische Informationsbibliothek Hannover

Place of publication of the digital copy:: Hannover

Year of publication of the original:: 2016

Document type:: Volume

Collection:: Earth sciences

Chapter

Title:: 3 Spectral signatures of objects. Chairman: G. Guyot, Liaison: N. J. J. Bunnik

Document type:: Multivolume work

Structure type:: Chapter

Chapter

Title:: Spectral and botanical classification of grasslands: Auxois example. C. M. Girard

Document type:: Multivolume work

Structure type:: Chapter

3.2 Reflectance data In order to characterize more fully and to compare more easily seasonal(phenological) variations of agro-ecologmcal units, we used reflectance data. A PCA performed on the ISCO measurements showed that the more useful wavelengths were: 550 nm (green) 675 nm (red), 850 and 1400 nm (near infra-red). The first two wavelengths are inversely correlated with chlorophyll a, and chlorophyll (a+b)/ carote noid respectively (Gates and all 1965, Knipling 1970) while the third is correlated with internal struc ture of leaves, and the last to water content(Gates 1970) . Variations of reflectance in red and near infra-red are linked with phenological and coverage variations of plants(Figure 2). Red low near IR high Plants with high chlorophyll content Red high near IR low Plants with less chlorophyll: dying or maturing A R% Red low near IR low * * R nIR Plants with high chlorophyll content but low coverage: soil showing Red high near IR high Plants with high chlorophyll and other pigment content: flowering. Figure 2. Variations of reflectance in red and near infra-red in relation with phenological and coverage varia tions of plants The reflectance values at each period, for each wave length of each agro-ecological unit was obtained by Calculating the mean of reflectance values of the different stations belonging to this agro-ecological unit. A PCA of the reflectance values in the 4 wavelengths at the 4 periods, for the 8 agro-ecological units enabled to draw a model of spectral behaviour through time (Figure 3). unit 1 : heliophilous and calcicolous grasslands and grazed rangelands on shallow soils with exces sive drainage. unit 2:grazed grasslands on steep èlope, shallow soil dry. unit 3 : grazed grasslands on slope, more or less shal low soil, dry. unit 4:grazed grasslands on middle or (bottom of slope deep, moist soil. unit 5:grazed grasslands on middle or bottom of slope deep, humid soil. unit 6:grazed grasslands on bottom of slope, deep, very humid soil. unit 7: grazed grasslands on bottom of valleys, or slope bogs on deep muddy soils. unit 8: grazed grasslands on bottom of valleys, or slope bogs on very muddy soils. Figure 3.Radiometric behaviour model for the 8 agro- ecological units according to red and near infra-red from PCA. This spectral behaviour of each unit varies accor ding to the nature, percent cover and phenological stages of the 26 more abundant species. According to its agro-ecological characteristics, each unit shows a more or less important ! .chlorophvll content and a long or short chlorophvllian activitv period. For example, chlorophyIlian activity period of helio philous and calcicolous grasslands and grazed range- lands on shallow soils with excessive drainage is short (May, June), while it is long(April till June) for grazed grasslands on middle or bottom of slope on deep, moist soils. This model has been tested with the three stations already used to validate the model for phytosociolo- gical relevés analysis. These stations are clustered respectively to units

Access restriction

Copyright

fullscreen: Remote sensing for resources development and environmental management (Volume 1)

Multivolume work

Volume

Chapter

Chapter

Table of contents

Cite and reuse

Volume

Chapter

Image

Image fragment

Citation links

Citation recommendation