Effects of artificially varying amounts of rainfall on two semi-natural grassland types

0382545 - ÚVGZ 2014 RIV NL eng J - Journal Article
Holub, Petr - Fabšičová, Martina - Tůma, I. - Záhora, J. - Fiala, Karel
Effects of artificially varying amounts of rainfall on two semi-natural grassland types.
Journal of Vegetation Science. Roč. 24, č. 3 (2013), s. 518-529. ISSN 1100-9233. E-ISSN 1654-1103
R&D Projects: GA ČR(CZ) GA526/06/0556; GA MZe QJ1220007; GA MŠMT(CZ) ED1.1.00/02.0073; GA MŠMT(CZ) LM2010007
Institutional support: RVO:67179843 ; RVO:67985939
Keywords : Above-ground net primary productivity * Climate change * Grasses * Irrigation * Precipitation * Rainout shelters * Species diversity
Subject RIV: EH - Ecology, Behaviour; EF - Botanics (BU-J)
Impact factor: 3.372, year: 2013

Question Is a lowland grassland community with a lower amount of ambient precipitation and a high abundance of subdominant species more sensitive to altered rainfall input in comparison with mountain grassland with higher ambient precipitation and a low abundance of subdominant species? Location (1) Lowland Festuca grassland characterized by dry acidophilous vegetation, low mean annual precipitation and high species richness, and (2) mountain Nardus grassland with high mean annual precipitation and low species richness in the Eastern Czech Republic. Methods We conducted a manipulative experiment with rainout shelters and gravity irrigation systems. We simulated three levels of precipitation input (50%, 100% and 150%) and examined the treatment effects on above-ground net primary productivity (ANPP) of the main plant functional groups (grasses, forbs, legumes, shrubs and mosses) and on plant species composition over three consecutive years. Results Altered rainfall input had a significant effect on total live ANPP in the drier, lowland grassland community, while no pronounced effect was observed in the mountain grassland characterized by higher ambient precipitation. In the lowland grassland, changes in total ANPP resulted primarily from enhanced growth of subdominant non-N-fixing forbs in response to the direct effect of higher artificial rainfall input and an indirect effect of reduced competition with grasses in drier treatments. Conclusions Wetter, species-poor mountain grasslands will probably show smaller changes in response to expected climate changes in ANPP, species number and abundance than lowland grasslands, characterized by dry acidophilous vegetation, with higher species richness and higher abundance of subordinate species.
Permanent Link: http://hdl.handle.net/11104/0212741