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| Titel |
Multifractal characteristics of NDVI maps in space and time in the Community of Madrid (Spain) |
| VerfasserIn |
Juan J. Martin Sotoca, Antonio Saá-Requejo, Juan B. Grau, Ana M. Tarquis |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250113925
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| Publikation (Nr.) |
 EGU/EGU2015-14967.pdf |
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| Zusammenfassung |
| Satellite information has contributed to improve our understanding of the spatial variability
of hydro-climatic and ecological processes. Vegetation activity is tightly coupled
with climate, hydro-ecological fluxes, and terrain dynamics in river basins at a
wide range of space–time scales (Scheuring and Riedi, 1994). Indices of vegetation
activity are constructed using satellite information of reflectance of the relevant
spectral bands which enhance the contribution of vegetation being Normalized
Difference Vegetation Index (NDVI) widely used. How can we study such a complex
system?
Multifractals and fractals are related techniques mainly used in physics to characterize the
scaling behaviour of a system; they differ in that fractals look at the geometry of
presence/absence patterns, while multifractals look at the arrangement of quantities such as
population or biomass densities (Saravia et al., 2012). Scaling laws are an emergent
general feature of ecological systems; they reflect constraints in their organization
that can provide tracks about the underlying mechanisms (Solé and Bascompte,
2006).
In this work, we have applied these techniques to study the spatial pattern through one
year of NDVI maps. A rectangular area that includes the Community of Madrid and part of
the surroundings, consisting of 300 x 280 pixels with a resolution of 500 x 500 m2 has been
selected and monthly NDVI maps analyzed using the multifractal spectrum and the map of
singularities (Cheng and Agterberg, 1996). The results show a cyclical pattern in the
multifractal behaviour and singularity points related to river basin networks (Martín-Sotoca,
2014).
References
Cheng, Q. and Agterberg, F.P. (1996). Multifractal modeling and spatial statistics. Math.
Geol. Vol 28, 1–16.
Martín-Sotoca, J.J. (2014) Estructura Espacial de la Sequía en Pastos y sus Aplicaciones
en el Seguro Agrario. Master Thesis, UPM (In Spanish).
Saravia LA, Giorgi A, Momo F.: Multifractal growth in periphyton communities. Oikos.
2012;121(11):1810–1820 10.1111/j.1600-0706.2011.20423.x
Scheuring, I., Riedi, R.H., 1994. Application of multifractals to the analysis of vegetation
pattern. J. Veg. Sci. 5, 489–496.
Solé RV, Bascompte J.: Self-organization in complex ecosystems. Princeton University
Press,2006.
Acknowledgements
First author acknowledges the Research Grant obtained from CEIGRAM in 2014 |
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