Differences in herbivory among woody species can greatly affect the functioning of forest ecosystems, particularly in species-rich (sub)tropical regions. However, the relative importance of the different plant traits which determine herbivore damage remains unclear. Defence traits can have strong effects on herbivory, but rarely studied geographical range characteristics could complement these effects through evolutionary associations with herbivores. Herein, we use a large number of morphological, chemical, phylogenetic and biogeographical characteristics to analyse interspecific differences in herbivory on tree saplings in subtropical China. Unexpectedly, we found no significant effects of chemical defence traits. Rather, herbivory was related to the plants' leaf morphology, local abundance and climatic niche characteristics, which together explained 70% of the interspecific variation in herbivory in phylogenetic regression. Our study indicates that besides defence traits and apparency to herbivores, previously neglected measures of large-scale geographical host distribution are important factors influencing local herbivory patterns among plant species.

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The reaction of terbuthylazine (TBA) with OH radicals was investigated in an aerosol smog chamber (2400 L). TBA was adsorbed well below a monolayer on silicon dioxide as inert carrier. OH radicals were produced from hydrogen peroxide, ozone, and nitrogen dioxide. The OH concentrations span a region of 10 5 e c OH /cm -3 e 10 7 and were monitored by the consumption of butane, 2,2dimethylbutane, pentafluorobenzene, 2,2,4,4-tetramethylbutane, and toluene as reference compounds. The OH rate constant of TBA obtained from nine smog chamber runs at T ) 300 K on the aerosol is k OH (TBA) ) (1.1 ( 0.2) × 10 -11 cm 3 s -1 . Beside the OH reaction, a loss path not initiated by OH radicals was found (k ) (1.9 ( 0.5) × 10 -5 s -1 ), which can be explained only in part by loss processes observed in the dark. Using the OH rate constant determined on the aerosol as an estimate for the corresponding OH reaction in the environment, a half-life of about 1 day (with OH concentrations of 5-10 × 10 5 cm -3 ) is obtained. Using the UV spectrum of TBA in hexane or in aqueous solution and known sunlight intensities a negligible loss by direct irradiation can be estimated. Furthermore, the ozone reactivity at T ) 300 K was measured to be negligible, too (k O3 (TBA) e 5 × 10 -19 cm 3 s -1 ). Hence, abiotic degradation of TBA in the environment (and assumed for all other chlorotriazines) is mainly attributed to OH radicals in the atmosphere. The main product of the OH radical reaction found on the aerosol is the corresponding acetyl-TBA, in addition to the des-alkylation product desethyl-TBA. τ )1

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Environmental context. Polyfluoroalkyl compounds, widely used chemicals in consumer and industrial products, are global pollutants in the environment. Transport mechanisms and environmental pathways of these compounds, however, are not yet fully understood. We show that a wastewater treatment plant can be an important source for polyfluoroalkyl compounds to the atmosphere where they have the potential to be transported long distances.Abstract. An air sampling campaign was conducted at a wastewater treatment plant (WWTP) to investigate air concentrations and particle-gas partitioning of polyfluoroalkyl compounds (PFCs). Samples were collected at an aeration tank and a secondary clarifier using both active high volume samplers and passive samplers comprising sorbentimpregnated polyurethane foam (SIP) disks. Water to air transport of PFCs was believed to be enhanced at the aeration tank owing to aerosol-mediated transport caused by surface turbulence induced by aeration. Mean air concentrations of target PFCs at the aeration tank were enriched relative to the secondary clarifier by factors of ,19, ,4 and ,3 for P fluorotelomer alcohols (FTOHs) (11 000 v. 590 pg m À3