Spectral monitoring of a system for the rehabilitation of burned soils based on inoculation with cyanobacteria and microalgae

• Type: Chapter or Part of a Book
• Date: 2022

Authors

Gonçalves, J (Author) Other; Marcos, B (Author) Other; Silva, MBd (Author) Other; Conceição, I (Author) Other; Pissarra, J (Author) Other; Roque, J (Author) Other; Paula Tamagnini (Author) FCUP; Melo, P (Author) FCUP; Pereira, R (Author) Other; Honrado, J (Author) Other

Book

Title: Advances in Forest Fire Research 2022

Pages: 381-384

ISBN: 9789892622989

Electronic ISBN: 9789892622972

Other information

Authenticus ID: P-00Y-5QR

DOI: 10.14195/978-989-26-2298-9_60

Abstract (EN): <jats:p>Inocula containing photosynthetic microorganisms such as cyanobacteria and microalgae can promote the formation of biocrusts, improving the soil properties and allowing ecosystem recovery. The GreenRehab project aims to develop a low-cost, eco-friendly, and easy-to-implement system to rehabilitate burned soils and protocols to evaluate the success of an ecosystem after-fire recovery. For this purpose, native cyanobacteria and microalgae were isolated from soil/biocrusts and tested, with selected strains being cultivated on a large scale. To evaluate the performance of the proposed rehabilitation system (based on the inoculation of native cyanobacteria and microalgae), we analyzed spectral data scanned from a portable visible/near-infrared spectrometer that indirectly estimates top-soil photosynthetic activity. Several spectral indices based on the normalized difference combination of spectral bands were calculated and compared for their ability to assess photosynthetic activity over time. Results showed that treatments with microalgae and cyanobacteria effectively enhanced photosynthetic activity, with Trichocoleus stimulating soil rehabilitation the most. Moreover, the best performing normalized difference index was the one combining the 660 nm and 860 nm wavelengths. Parallelly, very-high resolution imagery obtained from a UAV equipped with a multispectral camera is currently being tested to assess the performance of different inocula previously selected from microcosm experiments in environmental conditions closer to real ones found in post-fire scenarios. Preliminary results led us to develop an integrated protocol for image acquisition, radiometric calibration and photogrammetric post-processing. This allowed us to characterize baseline conditions in the test area, including geomorphology, vegetation and portray fine-scale patterns in greenness and photosynthetic activity. Overall, spectral measurements and indices from portable spectrometers and UAVs open the possibility of assessing which treatments exploited in the GreenRehab project effectively enhance soil rehabilitation and recovery from frequent fires. Such innovation may translate into other 'real-world' applications in ecology, forestry, and agronomy fields.</jats:p>

Language: English

Type (Professor's evaluation): Scientific