Remote Sensing Modeling Of Vegetation Phylogenetic Diversity Spatial Variation
Abstract
O.V. Zhukov, D.S. Ganzha, Y.Y. Dubinina
The features of the plant community phylogenetic organization of the Dnipro arena within the nature reserve "Dnieper-Orelsky» and the regularities of its spatial variation involving remote sensing of the earth's surface data have been stated. Materials have been collected in the period of 2012-2016 within a nature reserve. Research polygon is within the first terrace (arena) of the river Dnieper valley. The sandy steppe, meadow, forest and marsh communities in the river Protoch floodplain and beam Orlova, as well as artificial pine plantations have been found as being present within research polygon. The vegetation description has been carried out on sites 10×10 m (100 m2). Total 94 descriptions of the geobotanical sample have been made. Data on plant phylogeny have been obtained by Phylomatic service. Phylogenetic diversity of the communities has been assessed by indices Feith, Simpson and Shannon. Phylogenetic analysis has been performed by means of a double principal coordinate analysis (DPCo). Earth remote sensing data in the public domain have been obtained from EarthExplorer. Vegetation index have been calculated by images from the Sentinel satellites. Digital elevation model has been constructed with the Shuttle Radar Topography Mission (SRTM) data. At the points in space where the geobotanical samples were collected, the value of spatial predictors has been extracted (vegetation indices and geomorphological indicators derivated from DEM). A multiple linear regression analysis has been conducted between the values of the axes obtained by DPCoA and environment predictors. The kernel-based machine regression has been used for modeling spatial patterns of dependent variables. The vegetation cover has been found to be represented by 189 species within the investigated polygon. Abundance Phylogenetic Deviation (APD) for the investigated metacommunity has been evaluated to –0.53 which is statistically significantly different from random alternatives (p = 0.001). APD negative value indicates that phylogenetic organization of the investigated metacommunity is overdispersed. Permutation procedure have allowed to establish that the DPCoA-axes eigenvalues obtained from the real phylogenetic tree was significantly higher than their own number for the random phylogenetic trees for the first seven axes. This indicates that the first seven axes are useful for additional information on metacommunity ordination structure. The axes 1, 2, 3 and 6 largely have been found to be labeled by vegetation index. This means that decryption of satellite images may be interpreted in terms of recent phylogenetic features of vegetation. Axis 4 and 7 have marked by geomorphological predictors. Axis 5 to some extent independent of the predictors considered as a reflection of digression-demutation vegetation caused by anthropogenic impacts.
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