Line positions and intensities of the ν1{\nu}_1 band of 12^{12}CH3_3I using mid-infrared optical frequency comb Fourier transform spectroscopy

We present a new spectral analysis of the ${\nu}_1$ and ${\nu}_3$+${\nu}_1$-${\nu}_3$ bands of $^{12}$CH$_3$I around 2971 cm$^{-1}$ based on a high-resolution spectrum spanning from 2800 cm$^{-1}$ to 3160 cm$^{-1}$, measured using an optical frequency comb Fourier transform spectrometer. From this spectrum, we previously assigned the ${\nu}_4$ and ${\nu}_3$+${\nu}_4$-${\nu}_3$ bands around 3060 cm$^{-1}$ using PGOPHER, and the line list was incorporated in the HITRAN database. Here, we treat the two fundamental bands, ${\nu}_1$ and ${\nu}_4$, together with the perturbing states, 2${\nu}_2$+${\nu}_3$ and ${\nu}_2$+2${\nu}_6$$^{\pm2}$, as a four-level system connected via Coriolis and Fermi interactions. A similar four-level system is assumed to connect the ${\nu}_3$+${\nu}_1$-${\nu}_3$ and ${\nu}_3$+${\nu}_4$-${\nu}_3$ hot bands, which appear due to the population of the low-lying ${\nu}_3$ state at room temperature, with the 2${\nu}_2$+2${\nu}_3$ and ${\nu}_2$+${\nu}_3$-${\nu}_6$$^{\pm2}$ perturbing states. This treatment provides a good global agreement of the simulated spectra with experiment, and hence accurate line lists and band parameters of the four connected vibrational states in each system. Overall, we assign 4665 transitions in the fundamental band system, with an average error of 0.00071 cm$^{-1}$, a factor of two better than earlier work on the ${\nu}_1$ band using conventional Fourier transform infrared spectroscopy. The ${\nu}_1$ band shows hyperfine splitting, resolvable for transitions with J $\le$ 2 x K. Finally, the spectral intensities of 65 lines of the ${\nu}_1$ band and 7 lines of the ${\nu}_3$+${\nu}_1$-${\nu}_3$ band are reported for the first time using the Voigt line shape as a model in multispectral fitting

Occurrence of flat bugs (Heteroptera: Aradidae) in burned and unburned forests

The goal of this study was to determine the effect of fire on flat bug diversity and abundance in coniferous and mixed forests in interior Alaska. Eighty individuals, of which 78 in the burned areas and two in the control areas, of six aradid species were collected: Aradus abbas (Bergroth), A. funestus (Bergroth), A. lugubris (Fallén), A. signaticornis (Sahlberg), A. tuberculifer (Kirby) and Aneurus simplex (Uhler). Generally, all flat bug species were more abundant in the burned areas than in control areas with statistically significant differences for four of the six species and for pooled nymphs. Habitat preferences and potential mechanisms connecting mycophagy and pyrophagy are discussed

Short-term effects of continuous cover forestry on forest biomass production and biodiversity: Applying single-tree selection in forests dominated by Picea abies

The rotation forestry system provides high biomass production, but could also have a negative impact on species sensitive to disturbance. Continuous cover forestry (CCF) could contribute to solving these conflicting goals, but its feasibility in nutrient limited boreal forests is yet unresolved. In a unique experiment, we simultaneously assessed the short-term effect of single-tree selection on both biomass production and biodiversity (vascular plants, bryophytes, wood-inhabiting fungi), and tested fertilization as a way to mediate growth-biodiversity trade-offs. We found that unharvested stands and stands subjected to single-tree selection had a similar species assemblage of vascular plants, bryophytes, and wood-inhabiting fungi. Fertilization increased growth by 37% and induced shifts in two understory species (favoring the grass Avenella flexuosa and disfavoring the bryophyte Hylocomium splendens). We conclude that single-tree selection may become a useful tool to enhance biodiversity in managed forests

Line Positions and Intensities of the {\nu}4_4 Band of Methyl Iodide Using Mid-Infrared Optical Frequency Comb Fourier Transform Spectroscopy

We use optical frequency comb Fourier transform spectroscopy to measure high-resolution spectra of iodomethane, CH$_3$I in the C-H stretch region from 2800 to 3160 cm$^{-1}$. The fast-scanning Fourier transform spectrometer with auto-balanced detection is based on a difference frequency generation comb with repetition rate, f$_{rep}$, of 125 MHz. A series of spectra with sample point spacing equal to f$_{rep}$ are measured at different f$_{rep}$ settings and interleaved to yield sampling point spacing of 11 MHz. Iodomethane is introduced into a 76 m long multipass absorption cell by its vapor pressure at room temperature. The measured spectrum contains three main ro-vibrational features: the parallel vibrational overtone and combination bands centered around 2850 cm$^{-1}$, the symmetric stretch ${\nu}_1$ band centered at 2971 cm$^{-1}$, and the asymmetric stretch ${\nu}_4$ band centered at 3060 cm$^{-1}$. The spectra of the ${\nu}_4$ band and the nearby ${\nu}_3$+${\nu}_4$-${\nu}_3$ hot band are simulated using PGOPHER and a new assignment of these bands is presented. The resolved ro-vibrational structures are used in a least square fit together with the microwave data to provide the upper state parameters. We assign 2603 transitions to the ${\nu}_4$ band with standard deviation (observed - calculated) of 0.00034 cm$^{-1}$, and 831 transitions to the ${\nu}_3$+${\nu}_4$-${\nu}_3$ hot band with standard deviation of 0.00084 cm$^{-1}$. The hyperfine splittings due to the ${^{127}}$I nuclear quadrupole moment are observed for transitions with J$\leq$2xK. Finally, intensities of 157 isolated transitions in the ${\nu}_4$ band are reported for the first time using the Voigt line shape as a model in multispectral fitting

Long-term yield and biodiversity in stands managed with the selection system and the rotation forestry system: A qualitative review

There is an increasing interest in implementing Continuous Cover Forestry (CCF) as a tool to mitigate negative effects of the traditional rotation forestry system on biodiversity. However, the effects of CCF on forest growth and yield and on biodiversity is still poorly known. In this qualitative review, we compare biodiversity and longterm yield between the selection system, which is a type of CCF practiced in full-storied forests, and the traditional rotation forestry system. We specifically focus on forests dominated by Picea abies, which is a tree species of high economic relevance. Our literature search resulted in 17 publications on stand growth and yield and 21 publications on biodiversity. A majority of simulation studies found a higher long-term yield in the rotation forestry system, but it is challenging to conclude which system is the most productive. The magnitude of the difference in yield between systems, and how it varies across different environmental conditions, remains to be determined. For biodiversity, comparisons of species assemblage and individual species were only made to certain phases of the rotation cycle (recent clearcuts and middle-aged stands). Nevertheless, two aspects can be highlighted: i) the species assemblage in clearcuts differ substantially from stands managed with the selection system. Some of these effects may however be short lasting as examplified by studies on beetle assamblages showing that middle-aged rotation forestry stands become more similar to stands managed with the selection system, ii) the selection system maintains a similar species assemblage as the uncut control during the first years after cutting. In conclusion, management with the selection system may come with a loss in long-term stand yield, but much of the species assemblage is maintained after logging. We recommend future studies to specifically focus on long-term effects on biodiversity - in particular on species of conservation concern. There is also a need to establish a long-term research infrastructure to further develop the field