Figure 1.
Effects of warming on air and soil temperature.
Average percent increase in mean daily air temperature (25 cm above-ground, filled circles, solid line) and soil temperature (5 cm depth, open circles, dashed line) in warmig quadrates throughout the plant senescence process in 2011. Mean ± SD, n = 3.
Figure 2.
Effects of warming on chlorophyll concentration during the leaf senescence.
Decline in chlorophyll concentration for E. regelii (A), D. caeruleum (B), S. mussotii (C) and E. nutans (D) in warming and control quadrates during the leaf senescence in 2011. Error bars are SE (n = 3). Asterisks indicate significant differences for each collection in warming and control quadrates: ** indicate P<0.01; * indicates P<0.05.
Figure 3.
Effects of warming on N concentration during the plant senescence.
N loss in leaves (the left column) and culms (the right column) for E. regelii (A, B), S. mussotii (C, D), D. caeruleum (E, F) and E. nutans (G, H) during the plant senescence in autumn, 2011. Error bars are SE (n = 3). Asterisks indicate significant differences for each collection in warming and control quadrates: *** indicate P<0.001; * indicates P<0.05.
Figure 4.
TNC (Total non-structural carbohydrate) concentration in roots.
Accumulations of TNC measured (A, for E. regelii, S. mussotii, D. caeruleum and E. nutans) by the end of plant senescence in 2011 and (B, for D. caeruleum and E. nutans) in the beginning of spring in 2012. Error bars are SE (n = 3). Asterisks indicate significant differences (P<0.05) between warmed and control treaments. NS means not significant (P>0.05).
Figure 5.
Individual plant above-ground biomass in 2012.
Individual plant above-ground biomass for D. caeruleum and E. nutans (g, means ± SE, n = 8) measured (A) in the beginning of spring and (B) in late summer, 2012. Asterisks indicate significant differences (P<0.05) between warmed and control quadrates. NS means not significant (P>0.05).
Table 1.
Phenological parameters for D. caeruleum and E. nutans in warmed and control quadrates.