Climatic Aridity Shapes Post-Fire Interactions between Ceanothus spp. and Douglas-Fir (Pseudotsuga menziesii) across the Klamath Mountains

Climate change is leading to increased drought intensity and fire frequency, creating early-successional landscapes with novel disturbance–recovery dynamics. In the Klamath Mountains of northwestern California and southwestern Oregon, early-successional interactions between nitrogen (N)-fixing shrubs (Ceanothus spp.) and long-lived conifers (Douglas-fir) are especially important determinants of forest development. We sampled post-fire vegetation and soil biogeochemistry in 57 plots along gradients of time since fire (7–28 years) and climatic water deficit (aridity). We found that Ceanothus biomass increased, and Douglas-fir biomass decreased with increasing aridity. High aridity and Ceanothus biomass interacted with lower soil C:N more than either factor alone. Ceanothus biomass was initially high after fire and declined with time, suggesting a large initial pulse of N-fixation that could enhance N availability for establishing Douglas-fir. We conclude that future increases in aridity and wildfire frequency will likely limit post-fire Douglas-fir establishment, though Ceanothus may ameliorate some of these impacts through benefits to microclimate and soils. Results from this study contribute to our understanding of the effects of climate change and wildfires on interspecific interactions and forest dynamics. Management seeking to accelerate forest recovery after high-severity fire should emphasize early-successional conifer establishment while maintaining N-fixing shrubs to enhance soil fertility.

Unveiling the recovery dynamics of Walleye after the invisible collapse

Walleye (Sander vitreus) populations in Alberta, Canada collapsed by the mid-1990s and were a case study in the paper Canada’s Recreational Fisheries: The Invisible Collapse? Here we fit age-structured population dynamics models to data from a landscape-scale monitoring program to assess Walleye population status and reconstruct recruitment dynamics following the invisible collapse. Assessments indicated that populations featured low F_msy values of approximately 0.2-0.3 under conservative assumptions for the stock-recruitment relationship but that many populations were lightly exploited during 2000-2018. Recruitment reconstructions showed that recovery from collapse in 33/55 lakes was driven in part by large positive recruitment anomalies that occurred during 1998-2002. Additionally, 15/55 lakes demonstrated cyclic recruitment dynamics. Both the recruitment anomalies and cyclic fluctuations could be due to environmental effect(s) and(or) cannibalism, and experimentation may be necessary to resolve this uncertainty. These findings contribute new information on the recovery dynamics of Walleye following the invisible collapse, and demonstrate the effectiveness of coupling traditional fisheries science models with broad-scale monitoring data to improve understanding of population dynamics and sustainability across landscapes.

PSYCHOTHERAPY OF SLEEP DISORDERS: A TRANSDIAGNOSTIC APPROACH

This article actualises the issues of sleep disruption, awareness of youth about the importance of sleep for human body, highlights essential notions and research into the field of sleep disorders among adolescents carried out by us aiming to analyse the quality of sleep in the time of the global pandemic, occurence of nightmares and level of knowledge about the significance of sleep for human body. Insufficiency of awareness about the value of sleep, facing stress choosing to study at night, work at nighttime, leisure time at night among youth cause serious problems with health in the future. This article contains a survey of a vast array of research that give evidence of importance of sleep for human health, European recommendations on the sleep disorders treatment methods, descriptions of short medical cases, suggested by us new directions in medicine and psychology, which are developing, for solving problems in treating sleep disorders, studies carried out be us, best practises, sleep diary according to transdiagnostic approach for diagnostics and observation of recovery dynamics, methods of self-diagnosis and self-regulation etc. In conclusion, this material is a big step for increasing competencies of specialists in various directions who work with sleep disorders in medicine and psychology. Sleep disorders that are not of organic origin and require a separate or individual diagnostic protocol, night diagnosis (night diagnosis is what happens to a person at night), choice of therapies and therapeutic project for the treatment of post-traumatic sleep disorders and nightmares are described. A brief overview of our proposed new direction in medicine and psychology of somnotherapy, which is only developing in Ukraine and abroad. The term “somnotherapy” is proposed to mean not only a new direction in the treatment of sleep disorders and nightmares, but also a method of sleep treatment. As part of the new direction of “somnotherapy”, the article presents our proposed protocol of primary intervention for the treatment of sleep disorders, the algorithm of cooperation between a doctor and a psychologist-somnotherapist (patient / client route). We consider the results of the study to be a big step to increase the competence of specialists in various fields working with sleep disorders in medicine and psychology.