Screen Time and Socioemotional and Behavioural Difficulties Among Indigenous Children in Canada: Temps d'écran et difficultés socio-émotionnelles et comportementales chez les enfants autochtones du Canada.

OBJECTIVES: To describe screen time levels and determine their association with socioemotional and behavioural difficulties among preschool-aged First Nations, Métis, and Inuit children. METHOD: Data were taken from the Aboriginal Children's Survey, a nationally representative survey of 2-5-year-old Indigenous children in Canada. Socioemotional and behavioural difficulties were defined using parent/guardian reports on the Strengths and Difficulties Questionnaire. Multiple linear regression analyses were conducted separately for First Nations, Métis, and Inuit participants, and statistically adjusted for child age, child sex, and parent/guardian education. Statistical significance was set at P < 0.002 to adjust for multiple comparisons. RESULTS: Of these 2-5-year-old children (mean [M] = 3.57 years) 3,085 were First Nations (53.5%), 2,430 Métis (39.2%), and 990 Inuit (7.3%). Screen time exposure was high among First Nations (M = 2 h and 58 min/day, standard deviation [SD] = 1.89), Métis (M = 2 h and 50 min [SD = 1.83]), and Inuit children (M = 3 h and 25 min [SD = 2.20]), with 79.7% exceeding recommended guidelines (>1 h/day). After adjusting for confounders, screen time was associated with more socioemotional and behavioural difficulties among First Nations (total difficulties ß = 0.15 [95% CI, 0.12 to 0.19]) and Métis (ß = 0.16 [95% CI, 0.12 to 0.20]) but not Inuit children (ß = 0.12 [95% CI, 0.01 to 0.23]). CONCLUSIONS: Screen time exposure is high among Indigenous children in Canada, and is associated with more socioemotional and behavioural difficulties among First Nations and Métis children. Contributing factors could include enduring colonialism that resulted in family dissolution, lack of positive parental role models, and disproportionate socioeconomic disadvantage. Predictors of poor well-being should continue to be identified to develop targets for intervention to optimize the health and development of Indigenous children.

Mental Health Challenges Among First Nations Adolescents Living Off-Reserve in Ontario, Canada.

Limited data exist on the mental health challenges facing First Nations adolescents and the factors that modify these difficulties. The current study compared levels of common mental health challenges among 112 off-reserve First Nations and 3334 non-First Nations adolescents (12-17 years old) and examined the impact of maternal psychological distress on these mental health challenges. First Nations adolescents self-reported higher symptoms of conduct, oppositional-defiant, attention-deficit hyperactivity, major depressive, social phobia, generalized anxiety, and separation anxiety disorders and all associations remained statistically significant after adjusting for covariates. Moderation analyses found that increasing levels of maternal distress were associated more strongly with symptoms of oppositional defiant, attention-deficit hyperactivity, major depressive, and generalized anxiety disorders in First Nations adolescents. Future work aimed at improving the mental health of First Nations youth that focus on supporting these adolescents, and their mothers in particular, could result in substantial benefits.

Systematic Review and Meta-analysis: First Nations, Inuit, and Métis Youth Mental Health.

OBJECTIVE: The ongoing effects of colonialism disproportionately place Indigenous youth at risk for mental health challenges. This meta-analysis examined lifetime and past-year prevalence estimates of mental health challenges among First Nations, Inuit, and Métis youth in Canada. METHOD: Five electronic databases were searched from their inceptions until June 17, 2021. Studies were included if they assessed mental health challenges among First Nations, Inuit, and/or Métis youth (≤18 years old). Risk of bias was assessed using the Newcastle-Ottawa Scale. RESULTS: A total of 28 articles were eligible. Sixteen studies contained data on First Nations, 2 on Inuit, one on Métis, and 10 aggregated Indigenous participants. Among First Nations participants, pooled prevalence estimates for past-year suicidality (8.9%), mood and/or anxiety (<2.9%), attention-deficit/hyperactivity (2.9%), oppositional defiant (8.8%), and conduct (12.8%) disorder diagnoses were identified. Limited studies containing Inuit, Métis, and aggregated Indigenous participants also found high levels of disruptive disorder symptoms. Data were very limited for lifetime prevalence estimates. Studies assessed to have a moderate or high methodological risk of bias (k = 19) or using measures that are not yet culturally validated (k = 25) may contribute to inaccuracies in prevalence estimates. CONCLUSION: Existing data suggest that Indigenous youth have a low prevalence of mental health challenges, with the exception of disruptive behaviors. Future studies should use culturally validated tools and partner with Indigenous communities to ensure optimal identification of mental health challenges.

Psychopathology in the Offspring of Indigenous Parents with Mental Health Challenges: A Systematic Review: Psychopathologie des descendants de parents autochtones ayant des problèmes de santé mentale: Une revue systématique.

OBJECTIVE: Parental psychopathology is a significant risk factor for mental health challenges in offspring, but the nature and magnitude of this link in Indigenous Peoples is not well understood. This systematic review examined the emotional and behavioral functioning of the offspring of Indigenous parents with mental health challenges. METHOD: We searched MEDLINE, EMBASE, PsycINFO, CINAHL, and Web of Science from their inceptions until April 2020. Studies were included if they included assessments of emotional, behavioral, or other psychological outcomes in the offspring of Indigenous parents with a mental health challenge. RESULTS: The 14 studies eligible for review were focused on parental substance misuse (n = 8), maternal internalizing (i.e., depression, anxiety) issues (n = 5), and poor overall parental mental health (n = 4). In 11 studies, parental substance misuse, depression, and/or overall mental health challenges were associated with 2 to 4 times the odds of offspring externalizing and internalizing behaviors as compared to offspring of Indigenous parents without mental health challenges. CONCLUSION: The findings suggest higher risks of mental health challenges among offspring of Indigenous parents with psychiatric difficulties than among Indigenous children of parents without similar difficulties. Knowledge of these phenomena would be improved by the use of larger, more representative samples, culturally appropriate measures, and the engagement of Indigenous communities. Future studies should be focused on both risk and resilience mechanisms so that cycles of transmission can be interrupted and resources aimed at detection, prevention, and treatment optimally allocated.

Organic pollutants, heavy metals and toxicity in oil spill impacted salt marsh sediment cores, Staten Island, New York City, USA.

Sediment cores from Staten Island's salt marsh contain multiple historical oil spill events that impact ecological health. Microtox solid phase bioassay indicated moderate to high toxicity. Multiple spikes of TPH (6524 to 9586 mg/kg) and Σ16 PAH (15.5 to 18.9 mg/kg) were co-incident with known oil spills. A high TPH background of 400-700 mg/kg was attributed to diffuse sources. Depth-profiled metals Cu (1243 mg/kg), Zn (1814 mg/kg), Pb (1140 mg/kg), Ni (109 mg/kg), Hg (7 mg/kg), Cd 15 (mg/kg) exceeded sediment quality guidelines confirming adverse biological effects. Changes in Pb206/207 suggested three metal contaminant sources and diatom assemblages responded to two contamination events. Organic and metal contamination in Saw Mill Creek Marsh may harm sensitive biota, we recommend caution in the management of the 20-50 cm sediment interval because disturbance could lead to remobilisation of pre-existing legacy contamination into the waterway.

A 2000-year sediment record reveals rapidly changing sedimentation and land use since the 1960s in the Upper Mara-Serengeti Ecosystem.

The Mara River basin is a trans-boundary basin of international importance. It forms the headwaters of the Nile River and serves as the primary dry season water source for an estimated 1.1 million rural people and the largest remaining overland migration of 1.4 million wildebeest in the Serengeti-Mara Ecosystem. Changes throughout the basin are impacting the quantity and quality of the Mara River, yet the historical context of environmental conditions in the basin is not well known. We collected sediment cores throughout the wetland at the mouth of the Mara River, and we used isotopic dating methods and a suite of analyses to examine historical patterns of sediment quantity and source, mercury contamination, and carbon and nutrient loading. Our results show that ecological conditions in the Mara River basin were fairly stable over paleoecological time scales (2000-1000 years before present), but there has been a period of rapid change in the basin over the last 250 years, particularly since the 1960s. A shift in the source and quantity of sediments in the river began in the late 1700s and became much more pronounced in the 1950s and 1960s, coincident with increasing mercury concentrations. The quantity of sediment from the Upper Mara increased, particularly since 1960, but the proportion of total sediment from this region decreased as the Talek and Middle Mara portions of the basin began producing more sediment. The decadal oscillation in sediment accumulation was congruent with known periods of extreme precipitation events. Carbon and nitrogen loading also increased since the 1960s, and the shift in the isotopic ratio of nitrogen provides evidence for increased anthropogenic loading. Altogether, these data likely reflect patterns of change also experienced in other basins throughout East Africa.

Nitrogen and carbon concentrations and stable isotope ratios: Data from a 15N tracer study in short-form Spartina alterniflora and Distichlis spicata.

We present four datasets that provide information on primary production, nitrogen (N) uptake and allocation in two salt marsh grasses, short-form Spartina alterniflora and Distichlis spicata. These four datasets were generated during a month-long stable isotope (15N) tracer study described in the companion manuscript (Hill et al., 2018). They include an allometry dataset containing mass and height data for individual plants harvested from Colt State Park, Bristol, Rhode Island and used to nondestructively estimate plant masses. A second dataset contains weekly stem height measurements collected over the course of the 15N tracer study. Also included are high resolution data from 49 vegetated compartments (leaves, stems, fine/coarse roots, rhizomes) and bulk sediment depth intervals, reporting the mass, carbon and N concentrations, and stable isotope ratios measured following the harvest of cores over time. Additionally, we provide a complementary dataset with estimates of microbial removal from potential and ambient denitrification enzyme assays. These data, along with source code used in their analysis, are compiled in the NitrogenUptake2016 R package available from the Comprehensive R Archive Network.

Nitrogen uptake and allocation estimates for Spartina alterniflora and Distichlis spicata.

Salt marshes have the potential to intercept nitrogen that could otherwise impact coastal water quality. Salt marsh plants play a central role in nutrient interception by retaining N in above- and belowground tissues. We examine N uptake and allocation in two dominant salt marsh plants, short-form Spartina alterniflora and Distichlis spicata. Nitrogen uptake was measured using 15N tracer experiments conducted over a four-week period, supplemented with stem-level growth rates, primary production, and microbial denitrification assays. By varying experiment duration, we identify the importance of a rarely-measured aspect of experimental design in 15N tracer studies. Experiment duration had a greater impact on quantitative N uptake estimates than primary production or stem-level relative growth rates. Rapid initial scavenging of added 15N caused apparent nitrogen uptake rates to decline by a factor of two as experiment duration increased from one week to one month, although each experiment shared the qualitative conclusion that Distichlis roots scavenged N approximately twice as rapidly as Spartina. We estimate total N uptake into above- and belowground tissues as 154 and 277 mg N·m-2·d-1 for Spartina and Distichlis, respectively. Driving this pattern were higher N content in Distichlis leaves and belowground tissue and strong differences in primary production; Spartina and Distichlis produced 8.8 and 14.7 g biomass·m-2·d-1. Denitrification potentials were similar in sediment associated with both species, but the strong species-specific difference in N uptake suggests that Distichlis-dominated marshes are likely to intercept more N from coastal waters than are short-form Spartina marshes. The data and source code for this manuscript are available as an R package from https://github.com/troyhill/NitrogenUptake2016.

Effects of seasonality and environmental gradients on Spartina alterniflora allometry and primary production.

Predictions of how salt marsh primary production and carbon storage will respond to environmental change can be improved through detailed datasets documenting responses to real-world environmental variation. To address a shortage of detailed studies of natural variation, we examined drivers of Spartina alterniflora stem allometry and productivity in seven marshes across three regions in southern Louisiana. Live-stem allometry varied spatially and seasonally, generally with short stems weighing more (and tall stems weighing less) in the summer and fall, differences that persist even after correcting for flowering. Strong predictive relationships exist between allometry parameters representing emergent stem mass and mass accumulation rates, suggesting that S. alterniflora populations navigate a trade-off between larger mass at emergence and faster rates of biomass accumulation. Aboveground production and belowground production were calculated using five and four approaches, respectively. End-of-season aboveground biomass was a poor proxy for increment-based production measures. Aboveground production (Smalley) ranged from 390 to 3,350 g m-2 year-1 across all marshes and years. Belowground production (max-min) was on average three times higher than aboveground; total production ranged from 1,400 to 8,500 g m-2 year-1. Above- and belowground production were both positively correlated with dissolved nutrient concentrations and negatively correlated to salinity. SYNTHESIS: Interannual variation in water quality is sufficient to drive above- and belowground productivity. The positive relationship between nutrients and belowground production indicates that inputs of nutrients and freshwater may increase salt marsh carbon storage and ecosystem resilience to sea level rise.

Soil warming, carbon-nitrogen interactions, and forest carbon budgets.

Soil warming has the potential to alter both soil and plant processes that affect carbon storage in forest ecosystems. We have quantified these effects in a large, long-term (7-y) soil-warming study in a deciduous forest in New England. Soil warming has resulted in carbon losses from the soil and stimulated carbon gains in the woody tissue of trees. The warming-enhanced decay of soil organic matter also released enough additional inorganic nitrogen into the soil solution to support the observed increases in plant carbon storage. Although soil warming has resulted in a cumulative net loss of carbon from a New England forest relative to a control area over the 7-y study, the annual net losses generally decreased over time as plant carbon storage increased. In the seventh year, warming-induced soil carbon losses were almost totally compensated for by plant carbon gains in response to warming. We attribute the plant gains primarily to warming-induced increases in nitrogen availability. This study underscores the importance of incorporating carbon-nitrogen interactions in atmosphere-ocean-land earth system models to accurately simulate land feedbacks to the climate system.