Salt Marsh Response to Inlet Switch-Induced Increases in Tidal Inundation

There is widespread concern that rapidly rising sea levels may drown salt marshes by exceeding the rate at which these important ecosystems can build elevation. A significant fraction of marshes reside within backbarrier estuaries, yet little attention has been paid to how changes in inlet geometry influences estuarine tides and marshes. In 1898, a coastal storm eroded a new inlet through the barrier beach that fronts the North-South Rivers Estuary in Massachusetts, USA. The new inlet shortened the North River by 5.6 km and lengthened the South River channel by the same amount. Modern measurements of tidal attenuation suggest that channel shortening abruptly increased mean high tide along the North River by at least 30 cm. Foraminifera communities within North River marsh sediments indicated an environmental change from infrequent to frequent inundation at the time of the 1898 switch in inlet location, which supports this hypothesis. Increased mineral sediment deposition after the inlet switch played a dominant role in allowing marshes along the North River channel to adjust to greater inundation. Following the inlet switch, sediment accreted in North River marshes at 2–5 times the rate of sea level rise (SLR). The North River channel widened by an average of 18% relative to pre-1898 conditions to accommodate the increased tidal prism. The role of mineral sediment accretion in making this marsh resilient to an abrupt increase in inundation depth highlights the importance of maintaining adequate sediment supplies in coastal regions as SLR accelerates

Temporal and Spatial Variations in Microplastic Concentrations in Small Headwater Basins in the Southern Blue Ridge Mountains, North Carolina, USA

Microplastics (MPs) are ubiquitous contaminants of emerging concern that require additional study in freshwater streams. We examined the spatial-temporal variations in MP concentrations and characteristics within two headwater basins in the Southern Appalachian Mountains of western North Carolina over ~1 year. Atmospheric samples were also collected to determine the significance of atmospheric MP deposition to these relatively small streams. MP concentrations in both basins were within the upper quartile of those reported globally, reaching maximum values of 65.1 MPs/L. Approximately 90% of MPs were fibers. MP composition was dominated by polystyrene, polyamides, and polyethylene terephthalate. Spatially, concentrations were highly variable and increased with development, indicating anthropogenic inputs from urbanized areas. MP concentrations were also elevated in forested tributary subbasins with limited anthropogenic activity, suggesting atmospheric deposition was an important MPs source. Significant atmospheric inputs are supported by high atmospheric depositional rates (ranging between 7.6 and 449.8 MPs/m2/day across our study sites) and similarities in morphology, color, and composition between atmospheric and water samples. Temporally, MP concentrations during storm events increased, decreased, or remained the same in comparison to base flows, depending on the site. The observed spatial and temporal variations in concentrations appear to be related to the complex interplay between precipitation and runoff intensities, channel transport characteristics, and MP source locations and contributions

Exchange Flows in Tributary Creeks Enhance Dispersion by Tidal Trapping

Abstract The North River estuary (Massachusetts, USA) is a tidal marsh creek network where tidal dispersion processes dominate the salt balance. A field study using moorings, shipboard measurements, and drone surveys was conducted to characterize and quantify tidal trapping due to tributary creeks. During flood tide, saltwater propagates up the main channel and gets “trapped” in the creeks. The creeks inherit an axial salinity gradient from the time-varying salinity at their boundary with the main channel, but it is stronger than the salinity gradient of the main channel because of relatively weaker currents. The stronger salinity gradient drives a baroclinic circulation that stratifies the creeks, while the main channel remains well-mixed. Because of the creeks’ shorter geometries, tidal currents in the creeks lead those in the main channel; therefore, the creeks never fill with the saltiest water which passes the main channel junction. This velocity phase difference is enhanced by the exchange flow in the creeks, which fast-tracks the fresher surface layer in the creeks back to the main channel. Through ebb tide, the relatively fresh creek outflows introduce a negative salinity anomaly into the main channel, where it is advected downstream by the tide. Using high-resolution measurements, we empirically determine the salinity anomaly in the main channel resulting from its exchange with the creeks to calculate a dispersion rate due to trapping. Our dispersion rate is larger than theoretical estimates that neglect the exchange flow in the creeks. Trapping contributes more than half the landward salt flux in this region

Socioecology shapes child and adolescent time allocation in twelve hunter-gatherer and mixed-subsistence forager societies

A key issue distinguishing prominent evolutionary models of human life history is whether prolonged childhood evolved to facilitate learning in a skill- and strength-intensive foraging niche requiring high levels of cooperation. Considering the diversity of environments humans inhabit, children’s activities should also reflect local social and ecological opportunities and constraints. To better understand our species’ developmental plasticity, the present paper compiled a time allocation dataset for children and adolescents from twelve hunter-gatherer and mixed-subsistence forager societies (n = 690; 3–18 years; 52% girls). We investigated how environmental factors, local ecological risk, and men and women’s relative energetic contributions were associated with cross-cultural variation in child and adolescent time allocation to childcare, food production, domestic work, and play. Annual precipitation, annual mean temperature, and net primary productivity were not strongly associated with child and adolescent activity budgets. Increased risk of encounters with dangerous animals and dehydration negatively predicted time allocation to childcare and domestic work, but not food production. Gender differences in child and adolescent activity budgets were stronger in societies where men made greater direct contributions to food production than women. We interpret these findings as suggesting that children and their caregivers adjust their activities to facilitate the early acquisition of knowledge which helps children safely cooperate with adults in a range of social and ecological environments. These findings compel us to consider how childhood may have also evolved to facilitate flexible participation in productive activities in early life

The Associations of Dyadic Coping and Relationship Satisfaction Vary between and within Nations: A 35-Nation Study

Objective: Theories about how couples help each other to cope with stress, such as the systemic transactional model of dyadic coping, suggest that the cultural context in which couples live influences how their coping behavior affects their relationship satisfaction. In contrast to the theoretical assumptions, a recent meta-analysis provides evidence that neither culture, nor gender, influences the association between dyadic coping and relationship satisfaction, at least based on their samples of couples living in North America and West Europe. Thus, it is an open questions whether the theoretical assumptions of cultural influences are false or whether cultural influences on couple behavior just occur in cultures outside of the Western world. Method: In order to examine the cultural influence, using a sample of married individuals N = 7973) from 35 nations, we used multilevel modeling to test whether the positive association between dyadic coping and relationship satisfaction varies across nations and whether gender might moderate the association. Results: Results reveal that the association between dyadic coping and relationship satisfaction varies between nations. In addition, results show that in some nations the association is higher for men and in other nations it is higher for women. Conclusions: Cultural and gender differences across the globe influence how couples' coping behavior affects relationship outcomes. This crucial finding indicates that couple relationship education programs and interventions need to be culturally adapted, as skill trainings such as dyadic coping lead to differential effects on relationship satisfaction based on the culture in which couples live

The Associations of Dyadic Coping and Relationship Satisfaction Vary between and within Nations: A 35-Nation Study

Objective: Theories about how couples help each other to cope with stress, such as the systemic transactional model of dyadic coping, suggest that the cultural context in which couples live influences how their coping behavior affects their relationship satisfaction. In contrast to the theoretical assumptions, a recent meta-analysis provides evidence that neither culture, nor gender, influences the association between dyadic coping and relationship satisfaction, at least based on their samples of couples living in North America and West Europe. Thus, it is an open questions whether the theoretical assumptions of cultural influences are false or whether cultural influences on couple behavior just occur in cultures outside of the Western world

Corrigendum: The Associations of Dyadic Coping and Relationship Satisfaction Vary between and within Nations: A 35-Nation Study

A corrigendum on: The Associations of Dyadic Coping and Relationship Satisfaction Vary between and within Nations: A 35-Nation Study by Hilpert, P., Randall, A. K., Sorokowski, P., Atkins, D. C., Sorokowska, A., Ahmadi, K., et al. (2016). Front. Psychol. 7:1106. doi: 10.3389/fpsyg.2016.01106 Due to an oversight, the name of the author “Ahmad M. Alghraibeh” was incorrectly spelled as “Ahmad M. Aghraibeh.” The correct version is shown above. The authors apologize for this oversight. This error does not affect the scientific conclusions of the article in any way. The original article has been updated.[This corrects the article on p. 1106 in vol. 7, PMID: 27551269.]

The Associations of Dyadic Coping and Relationship Satisfaction Vary between and within Nations: A 35-Nation Study

Stress that spills over into one's intimate relationship (Repetti, 1989) can increase negative behavior between partners (Repetti, 1989; Schulz et al., 2004), which in turn can negatively affect relationship outcomes, such as satisfaction (Karney and Bradbury, 1995; Randall and Bodenmann, 2016). This negative stress spillover process may, however, be mitigated if couples help each other cope with the experienced stress (i.e., dyadic coping). Although theoretical assumptions, such as the systematic-transactional model of stress and dyadic coping (Bodenmann, 2005), suggest that the association between coping behavior and relationship satisfaction is determined by cultural influences (e.g., gender roles), findings from a recent meta-analysis shows that this association is stable across nations and gender (Falconier et al., 2015). Despite the significant findings, the samples used in the meta-analysis nearly exclusively relied on couples living in Western culture (Falconier et al., 2015), which leaves an unanswered question about how culture may affect the association between dyadic coping and relationship satisfaction. The goal of the current paper was to examine the cultural influence in dyadic coping processes based on 7973 married individuals across 35 nations