The response of litter decomposition to extreme drought modified by plant species, plant part, and soil depth in a temperate grassland.

Plant litter decomposition is a key ecosystem process in carbon and nutrient cycling, and is heavily affected by changing climate. While the direct effects of drought on decomposition are widely studied, in order to better predict the overall drought effect, indirect effects associated with various drought-induced changes in ecosystems should also be quantified. We studied the effect of an extreme (5-month) experimental drought on decomposition, and if this effect varies with two dominant perennial grasses, plant parts (leaves vs.

Field experiments underestimate aboveground biomass response to drought.

Researchers use both experiments and observations to study the impacts of climate change on ecosystems, but results from these contrasting approaches have not been systematically compared for droughts. Using a meta-analysis and accounting for potential confounding factors, we demonstrate that aboveground biomass responded only about half as much to experimentally imposed drought events as to natural droughts. Our findings indicate that experimental results may underestimate climate change impacts and highlight the need to integrate results across approaches.

Experimental drought indirectly enhances the individual performance and the abundance of an invasive annual weed.

During environmental change, invasive species may be favored by increased resource input or reduced resource use of the resident community. Plasticity in certain plant traits of invasive species may be one possible mechanism behind their ability to quickly exploit unused resources. We tested whether rainfall manipulations (severe drought, moderate drought, watering) alter the growth and reproductive success of the invasive annual Conyza canadensis, and if it translates into a change in the abundance of the species in a semiarid perennial grassland in Central Hungary.

Within-generation and transgenerational plasticity in growth and regeneration of a subordinate annual grass in a rainfall experiment.

Precipitation changes may induce shifts in plant species or life form dominance in ecosystems, making some previously subordinate species abundant. The plasticity of certain plant functional traits of these expanding subordinate species may be one possible mechanism behind their success. In this study, we tested if the subordinate winter annual grass Secale sylvestre shows plasticity in growth and reproduction in response to altered environment associated with field-scale rainfall manipulations (severe drought, moderate drought, and watering) in a semiarid grassland, and whether the maternal environment influences offspring germination or growth in a subsequent pot experiment.