Soil carbon stocks vary across geomorphic settings in Australian temperate tidal marsh ecosystems

Tidal marshes rank among the ecosystems with the highest capacity to sequester and store organic carbon (Corg) on earth. To inform conservation of coastal vegetated ecosystems for climate change mitigation, this study investigated the factors driving variability in carbon storage. We estimated soil Corg stocks in tidal marshes across temperate Western Australia and assessed differences among geomorphic settings (marine and fluvial deltas, and mid-estuary) and vegetation type (Sarcocornia quinqueflora and Juncus kraussii) linked to soil biogeochemistry. Soil Corg stocks within fluvial and mid-estuary settings were significantly higher (209 ± 14 and 211 ± 20 Mg Corg ha−1, respectively; 1-m-thick soils) than in marine counterparts (156 ± 12 Mg Corg ha−1), which can be partially explained by higher preservation of soil Corg in fluvial and mid-estuary settings rich in fine-grained ( \u3c 0.063 mm) sediments (49 ± 3% and 47 ± 4%, respectively) compared to marine settings (23 ± 4%). Soil Corg stocks were not significantly different between S. quinqueflora and J. kraussii marshes (185 ± 13 and 202 ± 13 Mg Corg ha−1, respectively). The higher contribution of tidal marsh plus supratidal vegetation in fluvial (80%) and intermediate (76%) compared to marine (57%) settings further explains differences in soil Corg stocks. The estimated soil Corg stocks in temperate Western Australia’s tidal marshes (57 Tg Corg within ~ 3000 km2 extent) correspond to about 2% of worldwide tidal marsh soil Corg stocks. The results obtained identify global drivers of soil Corg storage in tidal marshes and can be used to target hot spots for climate change mitigation based on tidal marsh conservation

Incidence of insulin-requiring diabetes in the US military

The aim of the study was to determine age- and race-related, and overall incidence rates of insulin-requiring diabetes in adults in the US military. Electronic records for admissions to US military and Tricare hospitals during 1990–2005 and visits to military clinics during 2000–2005 were identified using the Career History Archival Medical and Personnel System at the Naval Health Research Center, San Diego, CA, USA. Population data were obtained from the Defense Manpower Data Center and Defense Medical Epidemiology Database. In men there were 2,918 new cases of insulin-requiring diabetes in 20,427,038 person-years at ages 18–44 years (median age 28 years) for a total age-adjusted incidence rate of 17.5 per 100,000 person-years (95% CI 16.4–18.6). Incidence rates were twice as high in black men as in white men (31.5 vs 14.5 per 100,000, p < 0.001). In women there were 414 new cases in 3,285,000 person-years at ages 18–44 years (median age 27 years), for a total age-adjusted incidence rate of 13.6 per 100,000 (95% CI 12.4–14.9). Incidence rates were twice as high in black women as in white women (21.8 vs 9.7 per 100,000, p < 0.001). In a regression model, incidence of insulin-requiring diabetes peaked annually in the winter–spring season (OR 1.46, p < 0.01). Race and seasonal differences persisted in the multivariate analysis. Differences in incidence rates by race and season suggest a need for further research into possible reasons, including the possibility of a contribution from vitamin D deficiency. Cohort studies using prediagnostic serum 25-hydroxyvitamin D should be conducted to further evaluate this relationship

Global dataset on seagrass meadow structure, biomass and production

Seagrass meadows provide valuable socio-ecological ecosystem services, including a key role in climate change mitigation and adaption. Understanding the natural history of seagrass meadows across environmental gradients is crucial to deciphering the role of seagrasses in the global ocean. In this data collation, spatial and temporal patterns in seagrass meadow structure, biomass and production data are presented as a function of biotic and abiotic habitat characteristics. The biological traits compiled include measures of meadow structure (e.g. percent cover and shoot density), biomass (e.g. above-ground biomass) and production (e.g. shoot production). Categorical factors include bioregion, geotype (coastal or estuarine), genera and year of sampling. This dataset contains data extracted from peer-reviewed publications published between 1975 and 2020 based on a Web of Science search and includes 11 data variables across 12 seagrass genera. The dataset excludes data from mesocosm and field experiments, contains 14271 data points extracted from 390 publications and is publicly available on the PANGAEA® data repository (10.1594/PANGAEA.929968; Strydom et al., 2021). The top five most studied genera are Zostera, Thalassia, Cymodocea, Halodule and Halophila (84 % of data), and the least studied genera are Phyllospadix, Amphibolis and Thalassodendron (2.3 % of data). The data hotspot bioregion is the Tropical Indo-Pacific (25 % of data) followed by the Tropical Atlantic (21 %), whereas data for the other four bioregions are evenly spread (ranging between 13 and 15 % of total data within each bioregion). From the data compiled, 57 % related to seagrass biomass and 33 % to seagrass structure, while the least number of data were related to seagrass production (11 % of data). This data collation can inform several research fields beyond seagrass ecology, such as the development of nature-based solutions for climate change mitigation, which include readership interested in blue carbon, engineering, fisheries, global change, conservation and policy

Eco-engineering urban infrastructure for marine and coastal biodiversity: which interventions have the greatest ecological benefit?

Along urbanised coastlines, urban infrastructure is increasingly becoming the dominant habitat. These structures are often poor surrogates for natural habitats, and a diversity of eco-engineering approaches have been trialled to enhance their biodiversity, with varying success. We undertook a quantitative meta-analysis and qualitative review of 109 studies to compare the efficacy of common eco-engineering approaches (e.g. increasing texture, crevices, pits, holes, elevations and habitat-forming taxa) in enhancing the biodiversity of key functional groups of organisms, across a variety of habitat settings and spatial scales. All interventions, with one exception, increased the abundance or number of species of one or more of the functional groups considered. Nevertheless, the magnitude of effect varied markedly among groups and habitat settings. In the intertidal, interventions that provided moisture and shade had the greatest effect on the richness of sessile and mobile organisms, while water-retaining features had the greatest effect on the richness of fish. In contrast, in the subtidal, small-scale depressions which provide refuge to new recruits from predators and other environmental stressors such as waves, had higher abundances of sessile organisms while elevated structures had higher numbers and abundances of fish. The taxa that responded most positively to eco-engineering in the intertidal were those whose body size most closely matched the dimensions of the resulting intervention. Synthesis and applications. The efficacy of eco-engineering interventions varies among habitat settings and functional groups. This indicates the importance of developing site-specific approaches that match the target taxa and dominant stressors. Furthermore, because different types of intervention are effective at enhancing different groups of organisms, ideally a range of approaches should be applied simultaneously to maximise niche diversity

Heterogeneous tidal marsh soil organic carbon accumulation among and within temperate estuaries in Australia

The scarcity of data on tidal marsh soil accumulation rates (SAR) and soil organic carbon accumulation rates (CAR) globally precludes a comprehensive assessment of the role of tidal marshes in climate change mitigation and adaptation. Particularly few data exist from the southern hemisphere and for Australia in particular, which contains ~24% of globally recognised tidal marsh extent. Here we estimate SAR and CAR over the last 70 years using 210Pb-based geochronologies in temperate estuarine tidal marsh ecosystems in southern Western Australia (WA). Specifically, we assessed tidal marsh ecosystems situated in two geomorphic settings (marine vs. fluvial deltas) within 10 wave-dominated, barrier estuaries. Overall, average SAR (1.1 ± 0.3 mm yr−1) and CAR (32 ± 9 g m−2 yr−1) estimates were 5-fold lower than global mean estimates. Furthermore, we showed that hotspots of soil organic carbon stocks are not indicative of current hotspots for CAR. The lack of significant differences (P \u3e 0.05) in SAR, CAR, and excess 210Pb inventories between marine and fluvial settings can be explained by the high heterogeneity among and within estuaries throughout the region. The relative stability of recent and Holocene relative sea-levels in WA likely explains the limited CAR potential in tidal marshes under relatively stable sea-level conditions. However, further research exploring interactions among biotic and abiotic factors within estuaries is required to shed more light on the small spatial-scale variability in SAR and CAR across tidal marsh ecosystems in WA and elsewhere. This study provides baseline estimates for the inclusion of tidal marshes in national carbon inventories, identifies hotspots for the development of blue carbon projects, and supports the use of site-specific assessments opposed to regional means for estimating blue carbon resources

Caring and Curing

This collection of essays takes the reader from the early 19th century struggle between female midwives and male physicians right up to the late 20th century emergence of professionally trained women physicians vying for a place in the medical hierarchy. The bitter conflict for control of birthing and other aspects of domestic health care between female lay healers, particularly midwives, and the emerging male-dominated medical profession is examined from new perspectives.For Michael Moher and Toby Gelfan

Plasma 25-hydroxyvitamin D concentration and risk of type 2 diabetes and pre-diabetes: 12-year cohort study

<div><p>Background</p><p>It has been reported that higher plasma 25-hydroxyvitamin D is associated with lower risk of type 2 diabetes. However the results to date have been mixed and no adequate data based on a cohort are available for the high end of the normal range, above approximately 32 ng/ml or 80 nmol/L.</p><p>Methods</p><p>We performed a cohort study of 903 adults who were known to be free of diabetes or pre-diabetes during a 1997–1999 visit to a NIH Lipid Research Centers clinic. Plasma 25(OH)D was measured at Visit 8 in 1977–1979. The mean age was 74 years. The visit also included fasting plasma glucose and oral glucose tolerance testing.</p><p>Follow-up continued through 2009.</p><p>Results</p><p>There were 47 cases of diabetes and 337 cases of pre-diabetes. Higher 25(OH)D concentrations (> 30 ng/ml) were associated with lower hazard ratios (HR) for diabetes: 30–39 ng/ml or 75–98 nmol/L: HR = 0.31, 95% CI = 0.14–0.70; for 40–49 ng/ml or 100–122 nmol/L: HR = 0.29, CI = 0.12–0.68; for > 50 ng/ml or 125 nmol/L: HR = 0.19, CI = 0.06–0.56. All HRs are compared to < 30 ng/ml or 75 nmol/L. There was an inverse dose-response gradient between 25(OH)D concentration and risk of diabetes with a <i>p</i> for trend of 0.005. Each 10 ng/mL or 25 nmol/L higher 25(OH)D concentration was associated with a HR of 0.64, CI = 0.48–0.86. 25(OH)D concentrations were more weakly inversely associated with pre-diabetes risk, and the trend was not significant.</p><p>Conclusion</p><p>Further research is needed on whether high 25(OH)D might prevent type 2 diabetes or transition of prediabetes to diabetes.</p></div

Hazard ratios with 95% confidence intervals of type 2 diabetes incidence by categories of plasma 25(OH)D concentration adjusted for different combinations of confounding factors for diabetes, Rancho Bernardo cohort, 1997–2009.

<p>Hazard ratios with 95% confidence intervals of type 2 diabetes incidence by categories of plasma 25(OH)D concentration adjusted for different combinations of confounding factors for diabetes, Rancho Bernardo cohort, 1997–2009.</p

Hazard ratios with 95% confidence intervals of type 2 diabetes incidence by categories of plasma vitamin D metabolite concentrations by use of calcium supplements, Rancho Bernardo cohort, 1997–2009.

<p>Hazard ratios with 95% confidence intervals of type 2 diabetes incidence by categories of plasma vitamin D metabolite concentrations by use of calcium supplements, Rancho Bernardo cohort, 1997–2009.</p