The use of open‐top chambers in forests for evaluating warming effects on herbaceous understorey plants

Abstract

Open-top chambers (OTCs) are widely used experimental warming devices in open-field ecosystems such as tundra and alpine heath. However, knowledge of their performance in temperate deciduous forest ecosystems is largely lacking. The application of OTCs in forests might become important in the future since the effects of climate warming on growth, reproduction, and future distribution of understorey forest herbs have rarely been investigated. Therefore, polycarbonate OTCs covered with (OTCs+GF) and without permeable polypropylene GardenFleece (OTCs-GF) were installed in a temperate deciduous forest to create an experimental warming gradient. Short-term responses in phenology, growth, and reproduction of a model understorey forest herb (Anemone nemorosa L.) to OTC installation were determined. In a second growing season, an in-depth study of multiple abiotic conditions inside OTCs-GF was performed. Both OTCs+GF and OTCs-GF raised air and soil temperature in a realistic manner (ca. +0.4A degrees C to +1.15A degrees C), but OTCs-GF only in the leafless period (up to +1.5A degrees C monthly average soil temperature). The early flowering forest herb A. nemorosa also showed a clear phenotypic response to OTC installation. Based on these facts and the large ecological drawbacks associated with OTCs+GF (mostly in connection with a higher relative air humidity and a lower light quantity) and very modest abiotic changes in OTCs-GF, we encourage the use of OTCs-GF in deciduous forest ecosystems for evaluating climate-warming effects on early flowering understorey forest herbs. There is also a potential to use this warming method on later flowering species, but this needs further research

Reproductive system of a mixed-mating plant responds to climate perturbation by increased selfing

“…This above result differs from recent work on another V. praemorsa subspecies that did not demonstrate reproductive assurance [33]; however, we accounted for possible alternative explanations for our observed responses. In the field, climate chambers can potentially act as herbivore exclosures for deer or insects [34], but we saw no difference in herbivory. Climate chambers can also exclude pollinators, and undoubtedly visitation was constrained, but we detected no difference in pollen limitation.…”

Differential responses of ecosystem respiration components to experimental warming in a meadow grassland on the Tibetan Plateau

“…The OTCs used in the current study were similar to those described in other studies (Dabros and Fyles, 2010;De Frenne et al, 2010). The OTCs were made of 6 mm thick solar transmitting material; they were conical in shape, 40 cm in height, and covered an area of 2.01 m 2 at the ground.…”

Examination of Surface Temperature Modification by Open-Top Chambers along Moisture and Latitudinal Gradients in Arctic Alaska Using Thermal Infrared Photography

“…Passive warming [1][2][3][4][5][6][7]. Previous warming studies using OTCs have been directed toward analyzing specific species responses [8], radiation dynamics [9], plant phenology [10], snow regime shifts [11], and trace gas exchange [12,13] to name a few.…”

“…Previous warming studies using OTCs have been directed toward analyzing specific species responses [8], radiation dynamics [9], plant phenology [10], snow regime shifts [11], and trace gas exchange [12,13] to name a few. Studies have spanned multiple locations to include gradients; DeFrenne et al [5,6] examined transplants of forest understory species along a latitudinal gradient, and Oberbauer et al [13] studied ecosystem CO 2 fluxes in response to latitudinal and moisture gradients. Meta-analyses of many sites combined have quantified the impacts of passive warming treatments on tundra vegetation and indicate a warming climate in high latitudes and high elevations is changing plant communities and ecosystem function [14,15].…”