TanDEM-X for Large-Area Modeling of Urban Vegetation Height: Evidence from Berlin, Germany

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing

Johannes Schreyer¹  Christian Geis²  Tobia Lakes³ 

[1] Geoinformation Science Laboratory, Department of Geography, Humboldt-Universität zu Berlin, Berlin, Germany;German Remote Sensing Data Center, Geo-Risks, and Civil Security, German Aerospace Center (DLR), We&x00DF;ling, Germany;

关键词: Digital elevation model (DEM);    digital terrain model (DTM);    morphological filters (MFs);    normalized digital surface model (nDSM);    Tandem-X;    trees;   

DOI  :  10.1109/JSTARS.2015.2508660

来源: DOAJ

【 摘 要 】

Large-area urban ecology studies often miss information on vertical parameters of vegetation, even though they represent important constituting properties of complex urban ecosystems. The new globally available digital elevation model (DEM) of the spaceborne TanDEM-X mission has an unprecedented spatial resolution (12 × 12 m) that allows us to derive such relevant information. So far, suitable approaches using a TanDEM-X DEM for the derivation of a normalized canopy model (nCM) are largely absent. Therefore, this paper aims to obtain digital terrain models (DTMs) for the subsequent computation of two nCMs for urban-like vegetation (e.g., street trees) and forest-like vegetation (e.g., parks), respectively, in Berlin, Germany, using a TanDEM-X DEM and a vegetation mask derived from UltraCam-X data. Initial comparisons between morphological DTM-filter confirm the superior performance of a novel disaggregated progressive morphological filter (DPMF). For improved assessment of a DTM for urban-like vegetation, a modified DPMF and image enhancement methods were applied. For forest-like vegetation, an interpolation and a weighted DPMF approach were compared. Finally, all DTMs were used for nCM calculation. The nCM for urban-like vegetation revealed a mean height of 4.17 m compared to 9.61 m of a validation nCM. For forest-like vegetation, the mean height for the nCM of the weighted filtering approach (9.16 m) produced the best results (validation nCM: 13.55 m). It is concluded that an nCM from TanDEM-X can capture vegetation heights in their appropriate dimension, which can be beneficial for automated height-related vegetation analysis such as comparisons of vegetation carbon storage between several cities.

【 授权许可】

Unknown