Ecología del paisaje básica

Presentación del tema: "Ecología del paisaje básica"— Transcripción de la presentación:

1 Ecología del paisaje básica
Paisajes Neutrales Ecología del paisaje básica

2 Guia Qrule Neighborhood Analysis Enter map type to be analyzed: <I> Input existing map file <R> Generate a random map (with replacement) <S> Generate a simple random map <C> Generate a curdled (hierarchical) map <M> Generate a multifractal random map <G> Generate a multifractal random map with a gradient s Map choice: s Enter the number of map rows and columns Rows Columns Enter a negative random number seed Random number seed: Enter the neighborhood rule 1—nearest neighbor (N_nb = 4) 2—next nearest neighbor (N_nb = 8) 3—3rd nearest neighbor (N_nb = 12) 4—user defined 1 Rule choice is: 1 Enter the number of map classes Map classes = 1 Type in the 0th probability Type in the 1th probability. p(0) = p(1) = Enter the number of replications

3 Guía Qrule Enter the number of replications 10 N_Reps = 10 Create an output maps? N = None G = generated map S = cluster Size map I = cluster ID map B = both n Map output choice = N Perform map analysis? <L>acunarity, <R>ule, or <A>ll? r Analysis method: R Visualize map simulations <Y,N>

4 Archivos que produce Qrule
Nombre tipo Descripción rulerun.log G log file of program input and simulation results patch_cfd.dat patch size frequency distribution for each map and habitat type. Output includes mean patch size, edge, radius mean square, and fractal for each patch size. ‘Idfile’ output map with each patch uniquely identified ‘sizefile’ name of output map with the patch sizes uniquely labeled ‘outfile’ name of output map with habitat types uniquely labeled ‘mapfile’ I name of input map file for analysis by RULE assmat.dat matrix of neighbor association frequencies for each map arcgrid.map single map with header for input to ArcGrid for visualization and display lacun.dat output of lacunarity results

5 Analisis que realiza Qrule sobre el paisaje creado
Total clusters Total number of clusters on the map Total edges Total edge of all clusters Sav size Area weighted average cluster size. If Si is the size of the ith cluster, then Sav=Σ Si2 / S. S_Freq Total number of sites of current habitat type. P, the fraction of sites of the current habitat type, are estimated as P S_Freq / (nr * nc), where nr and nc are the number of rows and number of columns of the map, respectively. Cor_len Average mean squared radii of all clusters Perc/freq Frequency (percent of all maps) with a cluster large enough to span the dimensions of the map Largest cluster size Size of largest cluster (total number of grid units making up the largest cluster) Largest cluster edge Number of edges of largest cluster sites adjacent to a different habitat type Largest cluster fractal Fractal index of largest cluster estimated as ln(L.C.edge) / ln(average diameter of the cluster) Largest cluster_rms Mean squared radius of largest cluster (also known as the radius of gyration,). If ri is the ith of s sites in the cluster, then L.C._rms=Σ (ri rj)2 / s2. Diffuse sites of size s will have a larger L.C._rms than more compact sites.

6 Analisis que realiza Qrule sobre el paisaje creado
Percolación Cambios en conectividad en paisajes estructurados Flujos a través de parches (cluster) interconectados Ocurrencia de parches que ocupan una alta proporción del paisaje cuando el tipo de cobertura sobrepasa una probabilidad p

7 Analisis que realiza Qrule sobre el paisaje creado
Pc para la continuidad de los pastos de sabana es del 55-62% Percolación (un parche que conecta la mayor parte del paisaje) tiene una alta probabilidad de generarse a esta probabilidad Relación sabanas-bosques mantenidas por un proceso neutral de propagación de fuego

8 Niveles y H fractal Brownian motion in one dimension is produced by creating a series of steps, Xt, whose distance from the previous step (Xt + 1 − Xt) is randomly determined from a Gaussian distribution. A 3-dimensional map may be produced by allowing steps to occur in both the X and Y directions with the random displacements recorded as elevation The “fractal” of fractional Brownian motion is controlled by two parameters: The variance σ2 H correlation between successive steps Correlación entre puntos a distancia d determinada por C(d) = 22H-1 − 1 D=3-H

9 Lagunaridad Distribución de tamaño de los fragmentos Mandelbrot (1983)
Los objetos son mas lagunares si los tamaños de los fragmentos estan distribuidos sobre un rango amplio

10 Lagunaridad

11 Lagunaridad

12 Lagunaridad #lagunaridad plot(lacun.frag[,3],lacun.frag[,4])
points(lacun.frag[,3],lacun.frag[,4],col=lacun.frag[,1]) title("Lagunaridad vs número de pixeles")

13 Información de los parches
Patch_cfd.dat Calculated frecuency distribution para parches Frecuencias de mean patch size Edge radius mean square fractal dimension

14 Información de los parches
plot(patch[,3],patch[,5],xlab="size class",ylab="edge") points(patch[,3],patch[,5],col=patch[,1]) title("Tamaño de parche vs borde")

15 Información de los parches
Patch_cfd.dat Cummulative frecuency distribution para parches map number cover type size class Cumulative frequency patch Edges Radius fractal index