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Abstract Atacama Large Millimeter/submillimeter Array (ALMA) data toward QSO J1851+0035 (l= 33.°498,b= +0.°194) were used to study absorption lines by Galactic molecular gas. We detected 17 species (CO,13CO, C18O, HCO+, H13CO+, HCO, H2CO, C2H,c-C3H,c-C3H2, CN, HCN, HNC, CS, SO, SiO, and C) and set upper limits to 18 species as reference values for chemical models. About 20 independent velocity components at 4.7–10.9 kpc from the Galactic center were identified. Their column density and excitation temperature estimated from the absorption study, as well as the CO intensity distributions obtained from the FUGIN survey, indicate that the components withτ≲1 correspond to diffuse clouds or cloud outer edges. Simultaneous multiple-Gaussian fitting of COJ= 1–0 andJ= 2–1 absorption lines shows that these are composed of narrow- and broad-line components. The kinetic temperature empirically expected from the high HCN/HNC isomer ratio (≳4) reaches ≳40 K and the corresponding thermal width accounts for the line widths of the narrow-line components. CN-bearing molecules and hydrocarbons have tight and linear correlations within the groups. The CO/HCO+abundance ratio showed a dispersion as large as 3 orders of magnitude with a smaller ratio in a smallerN(HCO+) (or lowerAV) range. Some of the velocity components are detected in single-dish CO emission and ALMA HCO+absorption but without corresponding ALMA CO absorption. This may be explained by the mixture of clumpy CO emitters not resolved with the ∼1 pc single-dish beam surrounded by extended components with a very low CO/HCO+abundance ratio (i.e., CO-poor gas).
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Intraspecific Diversity in Thermal Performance Determines Phytoplankton Ecological Niche
ABSTRACT Temperature has a primary influence on phytoplankton physiology and ecology. We grew 12 strains ofGephyrocapsa huxleyiisolated from different‐temperature regions for ~45 generations (2 months) and characterised acclimated thermal response curves across a temperature range. Even with similar temperature optima and overlapping cell size, strain growth rates varied between 0.45 and 1 day−1. Thermal niche widths varied from 16.7°C to 24.8°C, suggesting that strains use distinct thermal response mechanisms. We investigated the implications of this thermal intraspecific diversity using an ocean ecosystem simulation resolving phytoplankton thermal phenotypes. Model analogues of thermal ‘generalists’ and ‘specialists’ resulted in a distinctive global biogeography of thermal niche widths with a nonlinear latitudinal pattern. We leveraged model output to predict ranges of the 12 lab‐reared strains and demonstrated how this approach could broadly refine geographic range predictions. Our combination of observations and modelled biogeography highlights the capacity of diverse groups to survive temperature shifts.
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- PAR ID:
- 10572638
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Ecology Letters
- Volume:
- 28
- Issue:
- 1
- ISSN:
- 1461-023X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1111/ele.70055
