Distribution drivers and physiological responses in geothermal bryophyte communities

Area of Science:

• Ecology
• Physiology
• Plant Science

Background:

• Understanding community structure requires defining the role of ecological niches.
• Few studies integrate predictive modeling with physiological measures for plant distributions.

Purpose of the Study:

• To predict distribution drivers for geothermal bryophyte communities using field surveys and statistical modeling.
• To correlate species-specific effects of relative humidity on distribution with physiological characters through drying and rewetting experiments.

Main Methods:

• Field surveys and statistical modeling were used to predict distribution drivers in geothermal bryophyte communities.
• Laboratory drying and rewetting experiments tested the link between predicted relative humidity effects and physiological responses.

Main Results:

• Temperature, light, and relative humidity significantly affected the distribution of the three most common geothermal bryophytes.
• Aulacomnium palustre, sensitive to humidity, showed stress and poor recovery after drying, aligning with model predictions.
• Campylopus introflexus, not humidity-dependent in models, maintained physiological efficiency after drying and rewetting.

Conclusions:

• Species-specific environmental stressors, particularly relative humidity, tightly constrain geothermal bryophyte ecological niches.
• Drying tolerance tests in bryophytes corresponded with model predictions of relative humidity's importance as a distribution driver.