48 research outputs found
Optimal stomatal behaviour around the world
This is the author accepted manuscript. The final version is available from Springer Nature via the DOI in this recordStomatal conductance (g s) is a key land-surface attribute as it links transpiration, the dominant component of global land evapotranspiration, and photosynthesis, the driving force of the global carbon cycle. Despite the pivotal role of g s in predictions of global water and carbon cycle changes, a global-scale database and an associated globally applicable model of g s that allow predictions of stomatal behaviour are lacking. Here, we present a database of globally distributed g s obtained in the field for a wide range of plant functional types (PFTs) and biomes. We find that stomatal behaviour differs among PFTs according to their marginal carbon cost of water use, as predicted by the theory underpinning the optimal stomatal model and the leaf and wood economics spectrum. We also demonstrate a global relationship with climate. These findings provide a robust theoretical framework for understanding and predicting the behaviour of g s across biomes and across PFTs that can be applied to regional, continental and global-scale modelling of ecosystem productivity, energy balance and ecohydrological processes in a future changing climate.This research was supported by the Australian Research Council (ARC MIA Discovery Project 1433500-2012-14). A.R. was financially supported in part by The Next-Generation Ecosystem Experiments (NGEE-Arctic) project, which is supported by the Office of Biological and Environmental Research in the Department of Energy, Office of Science, and through the United States Department of Energy contract No. DE-AC02-98CH10886 to Brookhaven National Laboratory. M.O.d.B. acknowledges that the Brassica data were obtained within a research project financed by the Belgian Science Policy (OFFQ, contract number SD/AF/02) and coordinated by K. Vandermeiren at the Open-Top Chamber research facilities of CODA-CERVA (Tervuren, Belgium)
Protecting new markets: quantifying the risks to new carbon markets from invasive species and prioritising areas for immediate action
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Para grass management and costing trial within Kakadu National Park
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Predicting the occurrence of riparian woody species to inform environmental water policies in an Australian tropical river
River flows are commonly altered by water resource development, with changes to the natural flow regime potentially impacting riparian vegetation. Increasingly, water resource managers seek to design policy to maintain healthy riparian ecosystems. Models that make explicit the relationship between hydrological variables and vegetation can be used by managers to assess vegetation response under different water management scenarios. We determined the potential impact of water-takeon the spatial distribution of woody riparian plant species in the lower Fitzroy River, in north-western Australia, an area under pressure to increase water resource development. We undertook a plant survey and developed and applied a joint species distribution model to determine the likelihood of occurrence for 26 woody riparian plant species, mapped species occurrence and assessed the change in species distribution under two water-take scenarios. We found that the duration of inundation from flood flows was a strong predictor of species occurrence in our joint species distribution model. We identified species associated with wetter environments, as indicated by their effect size for the inundation metric. Under the 300-Gl water-take scenario we found little change (<2%) in species occurrence, but under the 600-Gl scenario a decline between 5% and 7.4% was predicted for eight species associated with wetter habitats. This decline was generally confined to a localised area. Our approach highlights the usefulness of predictive modelling to identify species most likely to be impacted by water-take, and the benefit of linking modelling to spatial mapping because it can highlight areas where change is likely to occur. This information can assist management to protect ecologically and culturally important species.No Full Tex
