Natural methyl chloride (CH3Cl) and methyl bromide (CH3Br) emissions from coastal marsh ecosystems may constitute a significant proportion of stratospheric chlorine and bromine, which catalyze ozone depletion. Current inventories involve substantial uncertainties associated with upscaling plot-scale footprints (i.e., ≤1 m2). Here we present net ecosystem flux measurements of methyl halides from a brackish tidal marsh on the west coast of the United States between April 2016 and June 2017 using the relaxed eddy accumulation method. The measurement footprint encompasses a large part of the studied tidal marsh, including roughly 20 vascular plant species, open water, and soil surfaces. On the annual scale, ecosystem methyl halide emissions showed the strongest relationships to temperature and the growth cycle of halophyte vegetation, whereas on diurnal time scales, fluxes correlated the most with evapotranspiration. The maximum seasonal emissions occurred during the flowering season of Lepidium latifolium (perennial pepperweed), one of the most abundant halophytes on site. The maximum hourly emissions of 111 μg CH3Cl · m−2 s· hr−1 and 38 μg CH3Br · m−2 · hr−1 were observed during a heat wave in early June. Annually integrated emissions were 135 mg/m2 for CH3Cl and 21 mg/m2 for CH3Br, scaling up to 621 and 96 kg over the entire marsh. We provide a global salt marsh emission inventory that takes into account the spatial distribution of salt marshes in different climate zones, yielding a global salt marsh source of 31 Gg/year CH3Cl (range: 10 to 77) and 3 Gg/year CH3Br (range: 1 to 8).

Background

The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry.

Methods and results

A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up.

Conclusion

Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: https://www.clinicaltrials.gov. Unique identifier: NCT01090362.