The dataset consists of ACi (net CO2 assimilation rate, A, versus calculated substomatal CO2 concentration, Ci) curve data from an ozone experiment during which Trifolium repens and Lolium perenne were exposed as both monocultures and two-species mixtures to an episodic rural ozone regime in large, well-watered containers within solardomes for 12 weeks. Treatments were elevated ozone (AOT40 (Accumulated Ozone Threshold exposure of 40 parts per billion) of 12.86 ppm h) or control conditions (AOT40 of 0.02 ppm h). ACi curves were carried out mid-way and at the end of the exposure period using a Portable Photosynthesis System, CIRAS (PP-Systems) to calculate the photosynthetic parameters Jmax (maximum rate of photosynthetic electron transport) and Vcmax (maximum rate of Rubisco carboxylase activity). The observed decreases in photosynthetic efficiency and capacity in elevated ozone indicate that the ability of such ubiquitous vegetation to act as a sink for atmospheric carbon may be reduced in future climates. The experiment was carried out at the CEH Bangor Air Pollution Facility. This work was funded by the Centre for Ecology & Hydrology Integrating Fund Initiative. Full details about this dataset can be found at https://doi.org/10.5285/f14b9056-ccc0-4887-812e-c004f613a138

The data are biomass and ozone-injury data for white clover (Trifolium repens). Dataset concerns a 2014 study on the effects of Jasmonic acid/cutting in modulating the response of clover to ozone. A short-term (4-week) ozone-exposure experiment was conducted in 2014 to investigate the interactive effects of cutting on ozone-induced responses in white clover (Trifolium repens). A strong interaction was found in root biomass and root nodule biomass in cut white clover plants in a high ozone background (45-67 parts per billion (ppb) treatment mean), suggesting ozone-impacts on root nodule biomass occur through limitation of carbon availability. The work was carried out as part of a NERC funded PhD. Full details about this dataset can be found at https://doi.org/10.5285/10c6df00-c7ef-444b-951f-33a2c0072bec

The dataset consists of proportions of ozone injured or senesced leaves from a study which investigated how the presence of competing species in a community affects these two common responses to ozone. Monocultures and mixtures of Trifolium repens and Lolium perenne were grown in large containers and were exposed in solardomes to either a rural episodic ozone profile (AOT40 (Accumulated Ozone Threshold exposure of 40 parts per billion) of 12.86 ppm h) or control conditions (AOT40 of 0.02 ppm h) for 12 weeks. The proportion of ozone-injured or senesced leaves was determined in different regions of the canopy, the upper canopy (>14cm high), the canopy edge and the inner canopy, by separating injured/senesced leaves from healthy leaves. The experiment was carried out at the CEH Bangor Air Pollution Facility. This work was funded by the Centre for Ecology & Hydrology Integrating Fund Initiative Full details about this dataset can be found at https://doi.org/10.5285/bc4d0325-b67b-4fff-a14b-6e06edf397bd

The data are biomass measurements from an ozone exposure experiment, during which Trifolium repens and Lolium perenne were exposed as both monocultures and two-species mixtures to an episodic rural ozone regime in large, well-watered containers within solardomes for 12 weeks. Treatments were elevated ozone (AOT40 (Accumulated Ozone Threshold exposure of 40 parts per billion) of 12.86 ppm h) or control conditions (AOT40 of 0.02 ppm h). Measurements were dry weight, with a cutting height of 7cm above soil level. The distribution of plant material within the canopy was determined by separating material growing in the upper canopy (>14cm) from the canopy edge and the inner canopy for both species. The experiments were carried out in the CEH Bangor Air Pollution Facility. Work was funded by the Centre for Ecology & Hydrology Integrating Fund Initiative. The observed decreases in photosynthetic efficiency and capacity in elevated ozone indicate that the ability of such ubiquitous vegetation to act as a sink for atmospheric carbon may be reduced in future climates. Full details about this dataset can be found at https://doi.org/10.5285/5de90f7a-dec9-4bd5-af52-d0873a09d25d

This dataset contains RGB photographs acquired from drone surveys. There are 741 harvest plots from 38 surveys at 36 sites around the world. Each site was approximately 1 ha in area. Included with the photographic images are the coordinates of ground control markers, biomass, taxonomic and location data for harvest plots and ancillary metadata. The observations can be used to obtain allometric size-biomass models. This work was supported by the Natural Environment Research Council award number NE/R00062X/1 as part of the project 'Do dryland ecosystems control variability and recent trends in the land CO2 sink?' Full details about this dataset can be found at https://doi.org/10.5285/1ec13364-cbc6-4ab5-a147-45a103853424