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Epigeous fungal fruiting has important impacts on fungal reproduction and ecosystem function. Forest disturbances, such as timber harvest, impact moisture, host availability, and substrate availability, which in turn may drive changes in fungal fruiting patterns and community structure. We surveyed mushrooms in 0.4 ha patch cuts (18 months post-harvest) and adjacent intact hardwood forest in northern New Hampshire, USA, to document the effects of timber harvest on summer fruiting richness, biomass, diversity, and community structure of ectomycorrhizal, parasitic, and saprobic mushroom taxa. Fungal fruiting richness, diversity, and community heterogeneity were greater in intact forests than patch cuts. Among functional groups, ectomycorrhizal fruiting richness, diversity, and biomass were greater in unharvested areas than in the patch cuts, but parasitic and saprobic fruiting did not differ statistically between the two forest conditions. Our findings suggest that timber harvest simplifies fungal fruiting communities shortly after harvest, in particular triggering declines in ectomycorrhizal taxa which are important symbionts facilitating tree establishment and regeneration. Multi-aged silvicultural practices that maintain mature forest conditions adjacent to and throughout harvested areas through deliberate retention of overstory trees and downed woody material may promote fungal fruiting diversity in regenerating stands. Key words: ectomycorrhizal fungi, epigeous sporocarp, fungal fruiting body, forest disturbance, fungal diversity. La fructification des champignons epiges a des repercussions importantes sur la reproduction des champignons et la fonction de l'ecosysteme. Les perturbations de la foret, telles que la recolte de bois, ont un impact sur l'humidite ainsi que la disponibilite des hotes et du substrat, ce qui en retour peut amener des changements dans les patrons de fructification des champignons et la structure de la communaute. Nous avons inventorie les champignons dans des coupes par trouees de 0,4 ha (18 mois apres la recolte) et dans des forets feuillues adjacentes intactes dans le nord du New Hampshire, aux Etats-Unis, pour documenter les effets de la recolte de bois sur la diversite, la biomasse et la richesse des fructifications durant l'ete ainsi que sur la structure de la communaute des taxons de champignons ectomycorhiziens, parasites et saprobies. La richesse et la diversite des fructifications fongiques ainsi que l'heterogeneite des communautes etaient plus elevees dans les forets intactes que dans les coupes par trouees. Parmi les groupes fonctionnels, la richesse, la diversite et la biomasse des fructifications des champignons ectomycorhiziens etaient plus elevees dans les zones non recoltees que dans les coupes par trouees. Par contre, dans les deux situations la fructification des champignons parasites ou saprobies n'etait pas significativement differente. Nos resultats indiquent que la recolte de bois simplifie les fructifications des communautes fongiques peu de temps apres la recolte, surtout en provoquant le declin des taxons ectomycorhiziens, lesquels sont des symbiotes importants qui facilitent la regeneration et l'etablissement des arbres. Les pratiques sylvicoles inequiennes qui maintiennent les conditions de la foret mature adjacente aux zones recoltees et parmi ces zones par la retention deliberee d'arbres dominants et de materiel ligneux au sol, peuvent promouvoir la diversite des fructifications fongiques dans les peuplements en regeneration. [Traduit par la Redaction] Mots-cles : champignons ectomycorhiziens, sporocarpe epige, fructification fongique, perturbation de la foret, diversite fongique., Introduction Epigeous fungal sporocarps (mushrooms) play a critical role in fungal reproduction (Brown and Casselton 2001) and have secondary impacts on food webs (e.g., Orledge and Reynolds 2005), forest health [...]

In this work we used a Zeppelin NT equipped with six sensor setups, each composed of four different low-cost electrochemical sensors (ECS) to measure nitrogen oxides (NO and NO2), carbon monoxide, and Ox (NO2 + O3) in Germany. Additionally, a MIRO MGA laser absorption spectrometer was installed as a reference device for in-flight evaluation of the ECS. We report the influence of temperature on the NO and NO2 sensor outputs, but also find a shorter time scale (1 s) dependence of the sensors on the relative humidity gradient. To account for these dependencies, we developed a correction method that is independent of the reference instrument. After applying this correction to all individual sensors, we compare the sensor setups with each other and to the reference device. For the intercomparison of all six setups we find good agreements with R² ≥ 0.8, but different precisions for each sensor in the range of 1.45 to 6.32 ppb. The comparison to the reference device results in an R² of 0.88 and a slope of 0.92 for NOx (NO + NO2). Furthermore, the average noise (1 σ) of the NO and NO2 sensors reduces significantly from 6.25 ppb and 7.1 ppb to 1.95 ppb and 3.32 ppb, respectively. Finally, we highlight the potential use of ECS in airborne applications, by identifying different pollution sources related to industrial and traffic emissions during multiple commercial and targeted Zeppelin flights in spring 2020. These results are a first milestone towards the quality-assured use of low-cost sensors in airborne settings without a reference device, e.g., on unmanned aerial vehicles (UAVs). [ABSTRACT FROM AUTHOR]