Rapid bacterial and fungal successional dynamics in first year after chaparral wildfire.

The rise in wildfire frequency and severity across the globe has increased interest in secondary succession. However, despite the role of soil microbial communities in controlling biogeochemical cycling and their role in the regeneration of post-fire vegetation, the lack of measurements immediately post-fire and at high temporal resolution has limited understanding of microbial secondary succession. To fill this knowledge gap, we sampled soils at 17, 25, 34, 67, 95, 131, 187, 286, and 376 days after a southern California wildfire in fire-adapted chaparral shrublands. We assessed bacterial and fungal biomass with qPCR of 16S and 18S and richness and composition with Illumina MiSeq sequencing of 16S and ITS2 amplicons. Fire severely reduced bacterial biomass by 47%, bacterial richness by 46%, fungal biomass by 86%, and fungal richness by 68%. The burned bacterial and fungal communities experienced rapid succession, with 5-6 compositional turnover periods. Analogous to plants, turnover was driven by "fire-loving" pyrophilous microbes, many of which have been previously found in forests worldwide and changed markedly in abundance over time. Fungal secondary succession was initiated by the Basidiomycete yeast Geminibasidium, which traded off against the filamentous Ascomycetes Pyronema, Aspergillus, and Penicillium. For bacteria, the Proteobacteria Massilia dominated all year, but the Firmicute Bacillus and Proteobacteria Noviherbaspirillum increased in abundance over time. Our high-resolution temporal sampling allowed us to capture post-fire microbial secondary successional dynamics and suggest that putative tradeoffs in thermotolerance, colonization, and competition among dominant pyrophilous microbes control microbial succession with possible implications for ecosystem function.

The Development, Preliminary Validation, and Clinical Application of the Quick Parenting Assessment.

To prevent diseases, efforts are needed to determine how to address Adverse Childhood Experiences (ACEs), including parenting behaviors. The objective of this study, conducted in Nashville TN in 2017, was to initiate testing the psychometric properties of two new Adverse Childhood Experiences (ACEs) screening tools, the Quick Parenting Assessment (QPA) and Other Childhood Stressors (OCS). In a clinic serving low-income families, caregivers of children ages 2-10 completed assessments of parenting (QPA), other stressors (OCS), child behavior problems ((Strength and Difficulties Questionnaire (SDQ)), and Attitudes Toward Spanking (ATS). The QPA takes 1 min to complete and assesses for healthy and unhealthy parenting behaviors. Seventy-five percent of eligible participants completed the survey (N=558). A reduced 10-item QPA yielded a Cronbach's alpha of 0.79 and, in 4-10-year-olds, was associated with high SDQ conduct, hyperactivity, and total difficulties scores (r=0.44, 0.48, and 0.47; all p< 0.001). Children with QPAs of >4 were nine times more likely than those children with scores of ≤2 to have behavior problems (OR=8.93, 95% CI = 3.74-21.32). Elevated QPAs were associated with the ATS (r=0.47, p < .001). The OCS was also associated with high SDQ total difficulties scores (r=0.28, p< 0.001). Two pediatric ACEs screening tools, the QPA and the OCS, have promising psychometric properties. The findings suggest that parenting behaviors may play an outsized role in the pathogenesis of outcomes associated with ACEs. We discuss the clinical application of QPA at our institution and the theoretical potential for this instrument to reduce the rates of short- and long-term health problems.