Chris Neill and Kelly Holzworth graciously put together a blog post for the study that is now posted on the Ecosystems Center homepage. The Arctic LTER site that is managed by scientists at Ecosystems Center was the only arctic tundra site used in the study, included ~20 species of C3 herbs, evergreen shrubs, and deciduous shrubs, which fleshed out many PFT categories for the study. The Arctic plants had the highest rates of respiration per area when measured at the same temperature, which is to be expected.
More here: http://www.mbl.edu/ecosystems/global-study-of-tundra-to-desert-plants-shows-leaves-respond-to-warming-in-remarkably-similar-ways/
Very excited to announce that my paper on the temperature response of respiration in leaves is now out in PNAS
In brief, high-resolution temperature response curves (over 750 total) were measured in 231 dominant and common plant species from around the globe. We assessed which competing temperature response model best represented how respiration fluxes respond to warming, and found a second order polynomial was the most representative across a wide temperature range. Following that, we grouped species by biome and plant functional type, and found across these groupings, which are often applied in terrestrial biosphere models to estimate carbon fluxes, there were no significant differences in the shape parameters of the curve. In short, all these plants respond to short-term warming in a similar way across biomes and PFTs. We then applied this new model, our "global polynomial model" to the JULES terrestrial biosphere model to assess how it impacted how plant R was modeled compared to the traditional Q10=2 framework. Our model showed decreased leaf R in cold sites and in temperate sites at cold times of year.
The paper is receiving attention from the press as well. Some clippings below:
Also got some unexpected reddit coverage!
The author team is comprised of 19 authors (10 different nationalities) representing 12 institutions located in 6 countries; fieldwork occurred in 18 sites in Australia, Peru, Sweden, US, French Guiana, and Costa Rica, and was funded by US, Australian, UK govts. Proud to be part of this diverse team, work with excellent, supportive scientists, and analyze and present data that can hopefully simplify/improve how carbon fluxes are modeled in different ecosystems around the world.
Over multiple growing seasons, the B4Warmed experiment in Minnesota has warmed seedlings of evergreen and deciduous plants representing the northern-edge of southern-ranged species and the southern-edge of northern-ranged species. I was fortunate to work with the B4Warmed team for two summers in 2014 and 2013 taking measurements on the high-resolution short-term temperature response of dark respiration in leaves of these species (in ambient and warmed conditions). This week in Nature, Reich et al. describe their observations of acclimation in boreal and temperate forest species that are grown under this long-term elevated temperatures, and translate this acclimation impact into reduced carbon loss from respiration. They measured an incredible amount of R-T response curves, and found consistent patterns of acclimation - hopefully given much needed multi-species long-term support for including acclimation of R into larger-scale models.
I briefly discussed this paper and it's impact with a journalist, and the article was published in Science News: http://www.sciencemag.org/news/2016/03/some-trees-could-help-fight-climate-change
I was very nervous to talk to the press, since each experiment has it's own objective, and scaling beyond those objectives and context can be difficult. For instance, I am unfamiliar with how many DGVM models are run - the specific equations can vary and have their own set of parameters, to which acclimation may or may not be a large factor in how carbon is accounted. Recent articles by Slot et al. and Vanderwel et al. show consistent acclimation across a broad range of plant functional types and groups, using a range of datasets. Identifying these trends of acclimation within `10 species, very definitively as in Reich et al. or across many studies and published values (as in the Slot and Vanderwel papers) - are both highly useful, but these studies do not directly address the impact of acclimation on future land surface temperatures via model tests. Lombardozzi et al. recently aimed to incorporate acclimation into such models, and based on these new papers, and others, hopefully we can hone in on how to best quantitatively capture this response. And in the meantime, I'll still be nervous speaking to press about 'conclusions' since, in science, everything is a work in progress by definition.