Proportion and Correlates of Children in the US-Affiliated Pacific Region Meeting Sleep, Screen Time, and Physical Activity Guidelines.

INTRODUCTION: Limited data on 24-hour movement behaviors of children aged 5-8 years exist globally. We describe the prevalence and sociodemographic associations of meeting physical activity (PA), sedentary recreational screen time (ST), and sleep guidelines among children from 11 jurisdictions in the US-Affiliated Pacific region. METHODS: Cross-sectional representative data from 1192 children aged 5-8 years living in the US-Affiliated Pacific region were drawn from the baseline 2012-2014 Children's Healthy Living Program. Sleep and moderate- to vigorous-intensity PA were calculated from accelerometry. ST and sociodemographic data were collected from caregiver surveys. The percentage of children meeting the Asia-Pacific 24-hour movement guidelines for PA (≥60 min/d of moderate- to vigorous-intensity PA), sleep (≥9 and ≤ 11 h/d) and ST (≤2 h/d) were calculated. Generalized linear mixed models were used to examine associations with adiposity and sociodemographic variables. RESULTS: Twenty-seven percent (95% confidence interval, 24.6-30.0) of children met integrated guidelines; 98% (96.2-98.0) met PA, 78% (75.4-80.0) met sleep, and 35% (32.6-38.0) met ST guidelines. Females (adjusted odds ratio = 1.40 [95% confidence interval, 1.03-1.91]) and those living in lower-middle-income jurisdictions (2.29 [1.49-3.54]) were more likely to meet ST guidelines. Overweight children (0.62 [0.40-0.96]), those aged 8 years (0.39 [0.22-0.69]), and children with caregivers of an education level of high school or beyond (0.44 [0.29-0.68]) were less likely to achieve ST guidelines. Children from midrange annual household incomes were less likely to meet combined guidelines (0.60 [0.39-0.92]). CONCLUSIONS: Three-quarters of children are not meeting integrated Asia-Pacific 24-hour movement guidelines. Future strategies for reducing ST and increasing integrated guidelines compliance are needed.

Measuring the immeasurable: A structural equation modeling approach to assessing soil health.

Soil health is recognized as an important ecosystem property sensitive to human impact. As a concept, soil health cannot be directly measured, and so assessment and modeling efforts largely rely upon key biological, chemical, and physical indicators. Efforts to develop an overall soil health index are largely lacking due to significant statistical challenges and the necessity for regional calibration. Taken from the field of educational research, structural equation modeling (SEM) is an attractive approach to enhance the reliability and validity of soil health scoring. Therefore, SEM may be utilized to advance research efforts to understand management practices impacts on soil health. Our objectives were to develop a robust scoring function that (i) captures the concept of soil health and latent variables, (ii) adjusts scores by inherent soil properties and legacy of intensive land use to adequately reflect our regional conditions and contemporary land management, and (iii) meets the diverse practitioner needs. Through this process, we refined our minimum dataset of soil health indicators and reconceptualized soil health indicators into functional properties. Our results support the development of a robust single level or a multilevel SEM model-depending on the practitioner's goals-that accounts for repeated sampling or pseudoreplication. While the SEM scoring functions were highly related to the conventional scoring approach, SEM outperformed the conventional methods in terms of its wider distribution of scores-and thus enhanced discriminatory power on the lower and higher range of scores. We also confirmed that the SEM scoring function that includes adjustments for mineralogy and legacy of intensive land use successfully differentiates among contemporary management practices and land use. Therefore, we have confidence that the tool is reliable and appropriate to further examine more nuanced impacts of land use change and management practices within a given land use across time and space covering a diversity of soils. (300 words).

Edaphic controls of soil organic carbon in tropical agricultural landscapes.

Predicting soil organic carbon (SOC) is problematic in tropical soils because mechanisms of SOC (de)stabilization are not resolved. We aimed to identify such storage mechanisms in a tropical soil landscape constrained by 100 years of similar soil inputs and agricultural disturbance under the production of sugarcane, a C4 grass and bioenergy feedstock. We measured soil physicochemical parameters, SOC concentration, and SOC dynamics by soil horizon to one meter to identify soil parameters that can predict SOC outcomes. Applying correlative analyses, linear mixed model (LMM) regression, model selection by AICc, and hierarchical clustering we found that slow moving SOC was related to many soil parameters, while the fastest moving SOC was only related to soil surface charge. Our models explained 78-79%, 51-57%, 7-8% of variance in SOC concentration, slow pool decay, and fast pool decay, respectively. Top SOC predictors were roots, the ratio of organo-complexed iron (Fe) to aluminum (Al), water stable aggregates (WSagg), and cation exchange capacity (CEC). Using hierarchical clustering we also assessed SOC predictors across gradients of depth and rainfall with strong reductions in Roots, SOC, and slow pool decay associated with increasing depth, while increased rainfall was associated with increased Clay and WSagg and reduced CEC in surface soils. Increased negative surface charge, water stable aggregation, organo-Fe complexation, and root inputs were key SOC protection mechanisms despite high soil disturbance. Further development of these relationships is expected to improve understanding of SOC storage mechanisms and outcomes in similar tropical agricultural soils globally.

DNA-Stable Isotope Probing Shotgun Metagenomics Reveals the Resilience of Active Microbial Communities to Biochar Amendment in Oxisol Soil.

The functions and interactions of individual microbial populations and their genes in agricultural soils amended with biochar remain elusive but are crucial for a deeper understanding of nutrient cycling and carbon (C) sequestration. In this study, we coupled DNA stable isotope probing (SIP) with shotgun metagenomics in order to target the active community in microcosms which contained soil collected from biochar-amended and control plots under napiergrass cultivation. Our analyses revealed that the active community was composed of high-abundant and low-abundant populations, including Actinobacteria, Proteobacteria, Gemmatimonadetes, and Acidobacteria. Although biochar did not significantly shift the active taxonomic and functional communities, we found that the narG (nitrate reductase) gene was significantly more abundant in the control metagenomes. Interestingly, putative denitrifier genomes generally encoded one gene or a partial denitrification pathway, suggesting denitrification is typically carried out by an assembly of different populations within this Oxisol soil. Altogether, these findings indicate that the impact of biochar on the active soil microbial community are transient in nature. As such, the addition of biochar to soils appears to be a promising strategy for the long-term C sequestration in agricultural soils, does not impart lasting effects on the microbial functional community, and thus mitigates un-intended microbial community shifts that may lead to fertilizer loss through increased N cycling.

Biochar Properties Influencing Greenhouse Gas Emissions in Tropical Soils Differing in Texture and Mineralogy.

The ability of biochar applications to alter greenhouse gases (GHGs) (CO, CH, and NO) has been attracting research interest. However, inconsistent published results necessitate further exploration of potential influencing factors, including biochar properties, biochar rates, soil textures and mineralogy, and their interactions. Two short-term laboratory incubations were conducted to evaluate the effects of different biochars: a biochar with low ash (2.4%) and high-volatile matter (VM) (35.8%) contents produced under low-temperature (350°C) traditional kiln and a biochar with high ash (3.9%) and low-VM (14.7%) contents produced with a high-temperature (800°C) Flash Carbonization reactor and different biochar rates (0, 2, and 4% w/w) on the GHG emissions in a loamy-sand Ultisol and a silty-clay-loam Oxisol. In the coarse-textured, low-buffer Ultisol, cumulative CO and CH emissions increased with increasing VM content of biochars; however, CO emission sharply decreased at 83 µg VM g soil. In the fine-textured, high-buffer Oxisol, there were significant positive effects of VM content on cumulative CO emission without suppression effects. Regarding cumulative NO emission, there were significant positive effects in the Mn-rich Oxisol. Ash-induced increases in soil pH had negative effects on all studied GHG emissions. Possible mechanisms include the roles biochar VM played as microbial substrates, a source of toxic compounds and complexing agents reducing the toxicity of soil aluminum and manganese, and the role of biochar ash in increasing soil pH affecting GHG emissions in these two contrasting soils.

Children's Healthy Living Program (CHL) Indigenous Workforce Training to Prevent Childhood Obesity in the Underserved U.S. Affiliated Pacific Region.

The U.S. Affiliated Pacific Region (USAPR) is an underserved region with high rates of obesity-related, non-communicable diseases and a low proportion of trained obesity prevention professionals, especially indigenous professionals. The Children's Healthy Living Training Program was developed to enhance the USAPR's capacity to address childhood obesity prevention.

Nutrient concentrations within and below root zones from applied chicken manure in selected Hawaiian soils.

The objective of this study was to evaluate the effects of chicken manure (CM) application rates on nutrient concentrations within and below the root zone of sweet corn (Zea mays L. subsp. mays) under Hawaiian conditions. The research was conducted in leeward (Poamoho) and windward (Waimanalo) areas of Oahu, Hawaii, where contrasts exist in both climatic and soil conditions. Suction cup were used to collect soil solutions from 30 and 60 cm depths. Soil solutions were collected six times during the growing season at each location and analyzed for different nutrients (N, P, K, Ca, Mg, Na, Fe, Mn, Zn, and Cu), nitrate-nitrogen (NO(3)-N), ammonium-nitrogen (NH(4)-N), electrical conductivity (EC), and pH. Analysis showed that CM rates significantly affected the concentration of macro-nutrients below the root zone at Poamoho and within the root zone at Waimanalo. In general, nutrient concentration increased with the increasing rates of CM application. There was a significant effect of CM on micro-nutrients except below the root zone at Poamoho. CM significantly affected NO(3)-N concentration within the root zone for 15, 60 days after planting (DAP) at Poamoho, and 16, 28 DAP at Waimanalo. The effect was also significant on total nitrogen (N) concentration in the root zone across the two growing seasons at Waimanalo. There was a highly significant correlation between total N and NO(3)-N, and EC within and below the root zone.