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The ground flora stratum affects stand structure, resource acquisition, nutrient cycling, and taxonomic richness in forest ecosystems. Disturbances such as thinning and prescribed fire alter forest understory growing conditions that generally increase ground flora cover and richness. We studied annual changes in ground flora assemblages over three growing seasons after fire in thinned and frequently burned (3-year rotation) Pinus-Quercus stands. Our results corroborated trends from other studies that indicated greater ground flora richness and cover after thinning and burning compared with thin-only treatments. We also found that the stratum experienced relatively rapid succession between growing seasons that complimented the tolerance succession model. Forbs had reduced cover and richness from increasingly difficult growing conditions over time and were replaced by woody plants, shrubs, and seedlings. This likely occurred from changing competition dynamics that favored quick growth in the first growing season and long-term investment in vertical growth in the third growing season. The successful regeneration pathways also fit ground flora regeneration models and added a unique pathway to strengthen the predictive power of these models. As many stand management goals are focused towards improving biodiversity, prescribed fire and thinning may be used to increase understory richness in Pinus-Quercus stands.Résumé : La strate composée de la flore du sol influence la structure du peuplement, l'acquisition des ressources, le recyclage des nutriments et la richesse taxonomique dans les écosystèmes forestiers. Les perturbations, telles que l'éclaircie et le brûlage dirigé, modifient les conditions de croissance dans le sous-bois des forêts et augmentent généralement la richesse et le couvert de la flore du sol. Nous avons étudié les variations annuelles dans les assemblages de la flore du sol pendant trois saisons de croissance après feu dans des peuplements éclaircis et fréquemment brûlés (à tous les 3 ans) de pin et de chêne (Pinus et Quercus, respectivement). Nos résultats corroborent les tendances rapportées dans d'autres études indiquant que la richesse et le couvert de la flore du sol augmentent après une éclaircie et un brûlage comparativement à une éclaircie seule. Nous avons également trouvé que la strate connaissait une succession relativement rapide entre les saisons de croissance, ce qui va dans le sens du modèle de succession basé sur la tolérance. Le couvert et la richesse des plantes herbacées non graminoïdes ont diminué avec le temps à cause des conditions de croissance de plus en plus difficiles et elles étaient remplacées par des plantes ligneuses, des arbustes et des semis. Cela est survenu vraisemblablement à cause du changement dans la dynamique de la compétition qui a favorisé une croissance rapide durant la première saison de croissance et un investissement à long terme dans la croissance verticale durant la troisième saison de croissance. Les trajectoires qui favorisent la régénération correspon...

Light is the most common limiting factor in forest plant communities, influencing species composition, stand structure, and stand productivity in closed canopy stands. Stand vertical light structure is relatively simple under a closed canopy because most light is captured by overstory trees. However, wind disturbance events create canopy openings from local to landscape scales that increase understory light intensity and vertical light structural complexity. We studied the effects of an EF-1 tornado on horizontal and vertical (i.e. three-dimensional) light structure within a Quercus stand to determine how light structure changed with increasing disturbance severity. We used a two-tiered method to collect photosynthetic photon flux density at 4.67 m and 1.37 m above the forest floor to construct three-dimensional light structure across a canopy disturbance severity gradient to see if light intensity varied with increasing tornado damage. Results indicate that increased canopy disturbance closer to the tornado track increased light penetration and light structure heterogeneity at lower forest strata. Increased light intensity correlated with increased sapling density that was more randomly distributed across the plot and had shifted light capture higher in the stand structure. Light penetration through the overstory was most strongly correlated with decreased stem density in the two most important tree species (based on relative dominance and relative density) in the stand, Quercus alba L. (r =-0.31) and Ostrya virginiana (Mill.) K. Koch (r =-0.27, p \ 0.01), and indicated that understory light penetration was most affected by these two species. As managers are increasingly interested in patterning silvicultural entries on natural disturbances, they must understand residual stand and light structures that occur after natural disturbance events. By providing spatial light data that quantifies light structure post-disturbance, managers can use these results to improve planning required for long-term management. The study also provides comparisons with anthropogenic disturbances to the midstory that may offer useful comparisons to natural analogs for future silvicultural consideration.

Studies of the North American native wetland plant Phragmites australis (Cav.) Trin. ex Steud. subsp. americanus Saltonst., P.M. Peterson & Soreng have been hindered by chlorosistissue yellowing due to reduced chlorophyll productionwhile grown in controlled conditions, resulting in reduced growth. This study tested the effects of reduced iron [Fe(II)] and magnesium [Mg(II)], both important nutrients for chlorophyll production, on photosynthetic performance and growth of North American Phragmites, a plant of interest for wetland restoration and management. Plants were exposed to five treatments in a 13-week greenhouse experiment. Four of the treatments consisted of a factorial arrangement of Fe(II) and Mg(II) treatments (0.

Nostalgia has endured a negative societal perception since its inception, which influences how it is deployed in ecological restoration. However, the emotion has undergone a paradigmatic shift over the past 15 years with new quantitative psychological research providing insight into complex and oftentimes positive effects. In particular, personal nostalgia can increase social connectedness, optimism, self‐esteem, inspiration, openness, creativity, and charitable giving. Here, we view ecological nostalgia, which we define as a desire to return a degraded ecosystem to a past state that complements bittersweet memories of a better ecological period, as an accompanying motivator for applied ecological restoration. However, some restoration ecology circles presently reject the connection with nostalgia, which excludes potential benefits for restoration practices. We provide a survey of recent psychological nostalgia research to critique and reevaluate the stigma surrounding nostalgia in restoration. By doing so, we are optimistic that more informed views of nostalgia will be adopted by the restoration community to cautiously embrace a connection that can help motivate ecological restoration activities.