Combined use of LiDAR data and multispectral earth observation imagery for wetland habitat mapping

International audiencetAlthough wetlands play a key role in controlling flooding and nonpoint source pollution, sequesteringcarbon and providing an abundance of ecological services, the inventory and characterization of wetlandhabitats are most often limited to small areas. This explains why the understanding of their ecologicalfunctioning is still insufficient for a reliable functional assessment on areas larger than a few hectares.While LiDAR data and multispectral Earth Observation (EO) images are often used separately to mapwetland habitats, their combined use is currently being assessed for different habitat types. The aim ofthis study is to evaluate the combination of multispectral and multiseasonal imagery and LiDAR data toprecisely map the distribution of wetland habitats. The image classification was performed combiningan object-based approach and decision-tree modeling. Four multispectral images with high (SPOT-5)and very high spatial resolution (Quickbird, KOMPSAT-2, aerial photographs) were classified separately.Another classification was then applied integrating summer and winter multispectral image data andthree layers derived from LiDAR data: vegetation height, microtopography and intensity return. Thecomparison of classification results shows that some habitats are better identified on the winter image andothers on the summer image (overall accuracies = 58.5 and 57.6%). They also point out that classificationaccuracy is highly improved (overall accuracy = 86.5%) when combining LiDAR data and multispectralimages. Moreover, this study highlights the advantage of integrating vegetation height, microtopographyand intensity parameters in the classification process. This article demonstrates that information providedby the synergetic use of multispectral images and LiDAR data can help in wetland functional assessment© 2014 Elsevier B.V. All rights reserved