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2-Methylisoborneol (2-MIB) is a common off-flavor metabolite, and it has a very low odor threshold value. 2-MIB is produced by a variety of cyanobacteria and heterotrophic bacteria. In this study, Dolichospermum spiroides (Anabaena spiroides, FACHB 498) and Planktothrix sp. (FACHB 1371) were investigated. The influence of high temperature (27, 35 and 40 °C) and dissolved inorganic carbon (DIC, 18.4, 27.5 and 36.7 mg/L) on the two 2-MIB-producing cyanobacteria were simulated to study the effect of climate change on 2-MIB production. DIC had an effect on 2-MIB production by Planktothrix sp. The results showed that the highest DIC concentration (36.7 mg/L) led to the fastest algal growth, which increased 2-MIB production by Planktothrix sp. However, 40 °C killed all the cyanobacteria. The higher temperature (35 °C) shortened the lifecycle of the two cyanobacteria because it moved forward their logarithmic phase compared to 27 °C. The 2-MIB-producing potential of Dolichospermum spiroides may increase at 35 °C. The Dolichospermum spiroides results showed that the fluorescence intensity and the concentration of extracellular 2-MIB were highly correlated (r² ≥ 0.90). At 35 °C, there was a stronger correlation between extracellular dissolved organic matters' (DOMs, fulvic acid (P3 (r² = 0.90)), humic acid (P4 (r² = 0.92)) and the soluble microbial metabolites' (P5 (r² = 0.71)) fluorescence peak intensities and 2-MIB concentration. The Dolichospermum sproides 2-MIB-producing potential was affected by extracellular humus. The Planktothrix sp. 2-MIB-producing potential declined in general over the growth period. In addition, temperature had no significant effect on the Planktothrix sp. 2-MIB-producing potential and the extracellular 2-MIB component. [ABSTRACT FROM AUTHOR]

In environments that are hostile to Global Navigation Satellites Systems (GNSS), the precision achieved by a mobile light detection and ranging (LiDAR) system (MLS) can deteriorate into the sub-meter or even the meter range due to errors in the positioning and orientation system (POS). This paper proposes a novel least squares collocation (LSC)-based method to improve the accuracy of the MLS in these hostile environments. Through a thorough consideration of the characteristics of POS errors, the proposed LSC-based method effectively corrects these errors using LiDAR control points, thereby improving the accuracy of the MLS. This method is also applied to the calibration of misalignment between the laser scanner and the POS. Several datasets from different scenarios have been adopted in order to evaluate the effectiveness of the proposed method. The results from experiments indicate that this method would represent a significant improvement in terms of the accuracy of the MLS in environments that are essentially hostile to GNSS and is also effective regarding the calibration of misalignment. [ABSTRACT FROM AUTHOR]