Remote Sensing of Ecosystem Structure: Fusing Passive and Active Remotely Sensed Data to Characterize a Deltaic Wetland Landscape

Daniel Peters,Robert Skelly,K Olaf Niemann

doi:10.3390/rs12223819

Daniel Peters, Robert Skelly + Show 1 more

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https://doi.org/10.3390/rs12223819

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Abstract

A project was constructed to integrate remotely sensed data from multiple sensors and platforms to characterize range of ecosystem characteristics in the Peace–Athabasca Delta in Northern Alberta, Canada. The objective of this project was to provide a framework for the processing of multisensor data to extract ecosystem information describing complex deltaic wetland environments. The data used in this study was based on a passive satellite-based earth observation multispectral sensor (Sentinel-2) and airborne discrete light detection and ranging (LiDAR). The data processing strategy adopted here allowed us to employ a data mining approach to grouping of the input variables into ecologically meaningful clusters. Using this approach, we described not only the reflective characteristics of the cover, but also ascribe vertical and horizontal structure, thereby differentiating spectrally similar, but ecologically distinct, ground features. This methodology provides a framework for assessing the impact of ecosystems on radiance, as measured by Earth observing systems, where it forms the basis for sampling and analysis. This final point will be the focus of future work.

Highlights

The importance of wetlands, and associated ecological complexes, has been well-documented internationally (e.g., References [1,2,3])
Initial work to map the distribution of various vegetation/ecological complexes in the Peace–Athabasca Delta (PAD) was presented by the PAD-PG [53] based on 1970 air photos
Töyrä and Pietroniro [40] working with LANDSAT Thematic Mapper data (30 m spatial resolution), and its enhanced spectral band set over the original LANDSAT data, RADARSAT C-band microwave data, and a detailed light detection and ranging (LiDAR)-derived digital elevation model (DEM), were unable to expand significantly on the cover classes that could be resolved in prior work

Summary

Introduction

The importance of wetlands, and associated ecological complexes, has been well-documented internationally (e.g., References [1,2,3]). Given their importance, the Ramsar Convention on Wetlands came into force in 1975, certified by UNESCO in 1994, with the mission of “conservation and wise use of all wetlands through local and national actions and international cooperation, as a contribution towards achieving sustainable development throughout the world” [4]. The prominence of wetlands in the geomorphological, pedological, hydrological, and ecological continuum from well-drained upland to open-water environments have been extensively documented [5] and recognized in classification frameworks (e.g., References [6,7]). Important are the effects of climate on water balances and permafrost degradation, plus forest fires, and their role in changing lowland and the upland forest composition as they affect both the timing and magnitude of flows in fluvial systems, as well as the quality of waters that impact a particular wetland (e.g., References [13,14,15,16])

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