Eriophorum vaginatum is a tussock-forming sedge that contributes significantly to the structure and primary productivity of moist acidic tussock tundra. Locally adapted populations (ecotypes) have been identified across the geographical distribution of E. vaginatum; however, little is known about how their growth and phenology differ over the course of a growing season. The growing season is sh...

Little is known about the ability of trees to recover hydraulic conductance (k) within a growing season by regrowth or refilling of embolized conduits. Recovery of k lost to drought or other causes would prevent chronic reductions in gas exchange and productivity. To test recovery ability we conducted a 2-year experiment (2014-15) on a cohort of aspen ramets (Populus tremuloides, Michx.). Whole...

In boreal forests, fire is an important part of the ecosystem that greatly influences soil respiration, which in turn affects the carbon balance. Wildfire can have a significant effect on soil respiration and it depends on the fire severity and environmental factors (soil temperature and snow water equivalent) after fire disturbance. In this study, we quantified post-fire soil respiration durin...

The impact of elevated atmospheric CO2 on belowground plant growth is poorly understood relative to its effects on aboveground growth. We carried out a study of the seasonal dynamics of gross root production and death to determine how elevated CO2 affected the dynamics of net and gross root production through a full growing season. We quantified gross root production and root loss from sequenti...

[1] MODIS-based leaf area index (LAI) and normalized difference vegetation index (NDVI) are used to examine detailed information regarding actual growing season and total annual production for various regions. Overall, MODIS LAI has larger variability and demonstrates more information regarding the evolution and structure of the seasonal vegetation characteristics. In contrast, the NDVI saturat...

Alpine and northern treelines are primarily controlled by low temperatures. However, little is known about the impact of low soil temperature on tree transpiration at treelines. We aim to test the hypothesis that in cold-limited forests, the main limiting factors for tree transpiration switch from low soil temperature before summer solstice to atmospheric evaporative demand after summer solstic...