Meta-ecosystems and biological energy transport from ocean to coast: the ecological importance of herring migration

Ecosystems are not closed, but receive resource subsidies from other ecosystems. Energy, material and organisms are moved between systems by physical vectors, but migrating animals also transport resources between systems. We report on large scale energy transport from ocean to coast by a migrating fish population, the Norwegian spring-spawning (NSS) herring Clupea harengus. We observe a rapid body mass increase during parts of the annual, oceanic feeding migration and we use a bioenergetics model to quantify energy consumption. The model predicts strong seasonal variation in food consumption with a marked peak in late May to July. The copepod Calanus finmarchicus is the most important prey and 23×10⁶ tonnes (wet weight) of C. finmarchicus is consumed annually. The annual consumption-biomass ratio is 5.2. During the feeding migration 17% of consumed energy is converted to body mass. The biomass transported to the coast and left as reproductive output is estimated from gonad weight and is about 1.3×10⁶ tonnes for the current population. This transport is to our knowledge the world’s largest flux of energy caused by a single population. We demonstrate marked temporal variation in transport during the last century and discuss the effects of NSS herring in the ocean, as a major consumer, and at the coast, where eggs and larvae are important for coastal predators. In particular, we suggest that the rapid decline of lobster Homarus gammarus landings in Western Norway during the 1960s was related to the collapse of NSS herring. We also discuss spatial variation in energy transport caused by changed migration patterns. Both climate and fisheries probably triggered historical changes in the migration patterns of NSS herring. New migration routes emerge at the level of individuals, which in turn determines where resources are gathered and delivered, and therefore, how meta-ecosystems function.     

Arctic Geese Tune Migration to a Warming Climate but Still Suffer from a Phenological Mismatch

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Income inequality and depression: a systematic review and meta‐analysis of the association and a scoping review of mechanisms

Most countries have witnessed a dramatic increase of income inequality in the past three decades. This paper addresses the question of whether income inequality is associated with the population prevalence of depression and, if so, the potential mechanisms and pathways which may explain this association. Our systematic review included 26 studies, mostly from high‐income countries. Nearly two‐thirds of all studies and five out of six longitudinal studies reported a statistically significant positive relationship between income inequality and risk of depression; only one study reported a statistically significant negative relationship. Twelve studies were included in a meta‐analysis with dichotomized inequality groupings. The pooled risk ratio was 1.19 (95% CI: 1.07‐1.31), demonstrating greater risk of depression in populations with higher income inequality relative to populations with lower inequality. Multiple studies reported subgroup effects, including greater impacts of income inequality among women and low‐income populations. We propose an ecological framework, with mechanisms operating at the national level (the neo‐material hypothesis), neighbourhood level (the social capital and the social comparison hypotheses) and individual level (psychological stress and social defeat hypotheses) to explain this association. We conclude that policy makers should actively promote actions to reduce income inequality, such as progressive taxation policies and a basic universal income. Mental health professionals should champion such policies, as well as promote the delivery of interventions which target the pathways and proximal determinants, such as building life skills in adolescents and provision of psychological therapies and packages of care with demonstrated effectiveness for settings of poverty and high income inequality.     

Random size‐assortative mating despite size‐dependent fecundity in a Neotropical amphibian with explosive reproduction

Sexual selection theory predicts that, when body size is correlated with fecundity, there should be fitness advantages for mate choice of the largest females. Moreover, because larger males are expected to monopolise the largest females, this should result in an assortative mating based on body size. Although such patterns could be expected in both explosive and prolonged breeders, non‐assortative mating should be more widespread in species under time constraints. However, patterns of sexual selection are largely unexplored in explosive breeding species, and contrasting patterns have been found previously. We expect that the active choice of partners may be particularly risky when the time period during which sexual partners are available is severely limited. Therefore, to avoid missing an entire reproductive act, males and females should pair irrespective of traits, such as body size. We tested this hypothesis by investigating the mating patterns of the Pacific horned toad, Ceratophrys stolzmanni, a short‐lived fossorial species inhabiting Neotropical dry forests. This species is particularly adequate to test our prediction because it reproduces explosively over the course of a single night per year. Although the number of eggs laid was proportional to the size of females, and individuals of both sexes showed variation in body size, there was no assortative mating based either on size, body condition or age of mates. Egg size was not influenced by either female size or clutch size. The larger body size of females compared to males is likely due to fecundity selection, that is, the selective pressure that enhances reproductive output. Although we cannot dismiss the possibility that individuals could select their partners based on other criteria than those related to size or age, the results fit well our prediction, showing that the explosive breeding makes improbable an active choice of partners in both sexes and therefore favours a random mating pattern.     

Transracial adoption: white American adoptive mothers’ constructions of social capital in raising their adopted children

In the field of adoption and child welfare, there is ongoing debate and discussion about how white adoptive parents in transracial families construct personal and social relationships and networks to promote cultural belonging and identity development in their children. In spite of this however, there is, to date, no research study that has sought to apply the notion of social capital to understand transracial adoptive families. With its exploration of how white American adoptive mothers construct social capital in raising their transracially adopted children, this paper seeks to contribute to the literature on social capital and families in general, and social capital and transracial families in particular. By drawing upon a qualitative study involving white adoptive mothers’ discursive practices, and multiplex constructions of intersectionality, the paper seeks to offer rich theoretical and empirical insights into social capital and transracial adoption to contribute to the literature in this area.     

通用选择指数原理

本文在对各类种畜评定方法探讨的基础上,提出了通用选择指数概念,对各类评定方法在理论上加以综合,推导出统一的计算公式,并编制出相应的计算程序。为充分利用种畜各种信息,特别是为在多信息来源需作约束、最宜选择时的种畜评定,提供了行之有效的计算方法。避免了在实际应用时对各类评定方法的独立探讨以及因多种计算体系导致应用上的混乱。此外,本文还得出了有关选择理论的三个结论,并改正了文献[2]中的失误之处。     

Capital in the American carbon,energy, and material footprint

Stocks of fixed capital play a vital role in fulfilling basic human needs and facilitating industrial production. Their build‐up requires great quantities of energy and materials, and generates greenhouse gas emissions and other pollution. Capital stocks influence economic production and environmental pollution through their construction and over subsequent decades through their use. We perform an environmental footprint analysis of total consumption, capital investment, and capital consumption in the United States for 2007 and 2012. In 2012, capital consumption accounted for 13%, 19%, and 40% of total carbon, energy, and material footprints, respectively. Housing, federal defense, state and local government education and other services (including household consumption of roads), personal transport fuels, and hospitals are the consumption sectors with largest capital footprints. These sectors provide fundamental needs of shelter, transport, education, and health, underlying the importance of capital services. Endogenizing capital causes the biggest proportional increase to footprints of sectors with low environmental multipliers. This work builds upon existing input‐output models of production and consumption in the United States, and provides a capital‐inclusive database of carbon, energy, and material footprints and multipliers for 2007 and 2012. This article met the requirements for a gold – gold JIE data openness badge described at http://jie.click/badges .     

Application of a fluoride selective electrode to the stoichiometric analysis of lithium carbonate for nuclear purposes

An improved version of a potentiometric method for the determination of lithium has been applied to the accurate, high precision analysis of lithium carbonate, a raw material for the solid-state synthesis of lithium metazirconate (Li₂ZrO₃). This is one of the most promising tritium breeders in fusion reactors. The analytical procedure consisted of a decomposition of the sample in hydrochloric acid followed by evaporation to dryness. The residual lithium chloride was then dissolved in ethanol and titrated with ammonium fluoride in water-ethanol (1 + 1). A lanthanum fluoride solid-state ion-selective electrode was used as end point detector. By increasing the analyte concentration and by dissolving the titrant in the mixed solvent, more accurate results were achieved with respect to the older procedure. A comparison of the results obtained by this method and those obtained by ion-exchange showed no significant difference (P = 0.05). The precision in terms of relative standard deviation was 0.3-0.4%.     

What is the appropriate timescale for measuring costs of reproduction in a `capital breeder' such as the aspic viper?

Before we can quantify the degree to which reproductive activities constitute a cost (i.e., depress an organism's probable future reproductive output), we need to determine the timescale over which such costs are paid. This is straightforward for species that acquire and expend resources simultaneously (income breeders), but more problematical for organisms that gather resources over a long period and then expend them in a brief reproductive phase (capital breeders). Most snakes are capital breeders; for example, female aspic vipers (Vipera aspis) in central western France exhibit a 2- to 3-year reproductive cycle, with females amassing energy reserves for one or more years prior to the year in which they become pregnant. We use long-term mark-recapture data on free-living vipers to quantify the appropriate timescale for studies of reproductive costs. Annual survival rates of female vipers varied significantly during their cycle, such that estimates of survival costs based only on years when the females were ‘reproductive’ (i.e., produced offspring) substantially underestimated the true costs of reproduction. High mortality in the year after reproducing was apparently linked to reproductive output; low energy reserves (poor body condition) after parturition were associated with low survival rates in the following year. Thus, measures of cost need to consider the timescale over which resources are gathered as well as that over which they are expended in reproductive activities. Also, the timescale of measurement needs to continue long enough into the post-reproductive period to detect delayed effects of reproductive ‘decisions’. This revised version was published online in July 2006 with corrections to the Cover Date.     

Use of Industrial By‐Products in Urban Roadway Infrastructure

Incorporating the beneficial use of industrial by‐products into the industrial ecology of an urban region as a substitute or supplement for natural aggregate can potentially reduce life cycle impacts. This article specifically looks at the utilization of industrial by‐products (IBPs) (coal ash, foundry sand, and foundry slag) as aggregate for roadway sub‐base construction for the Pittsburgh, Pennsylvania, urban region. The scenarios compare the use of virgin aggregate with the use of a combination of both virgin and IBP aggregate, where the aggregate material is selected based on proximity to the construction site and allows for minimization of transportation impacts. The results indicate that the use of IBPs to supplement virgin aggregate on a regional level has the potential of reducing impacts related to energy use, global warming potential, and emissions of nitrogen oxides (NO_x), sulfur dioxide (SO₂), carbon monoxide (CO), PM₁₀ (particulate matter—10 microns), mercury (Hg), and lead (Pb). Regional management of industrial by‐products would allow for the incorporation of these materials into the industrial ecology of a region and reduce impacts from the disposal of the IBP materials and the extraction of virgin materials and minimize the impacts from transportation. The combination of reduced economic and environmental costs provides a strong argument for state transportation agencies to develop symbiotic relationships with large IBP producers in their regions to minimize impacts associated with roadway construction and maintenance—with the additional benefit of improved management of these materials.