Рубрики:
DEPENDENT ENERGY-DISSIPATION
XANTHOPHYLL CYCLE
ALPINE-TREELINE
LOW-TEMPERATURE
SNOW GUM
SEEDLINGS
GROWTH
PLANTS
LIGHT
PHOTOSYNTHESIS
Кл.слова (ненормированные):
environmental stress -- excitation pressure -- Pinus sylvestris -- Siberia -- xanthophyll cycle
DEPENDENT ENERGY-DISSIPATION
XANTHOPHYLL CYCLE
ALPINE-TREELINE
LOW-TEMPERATURE
SNOW GUM
SEEDLINGS
GROWTH
PLANTS
LIGHT
PHOTOSYNTHESIS
Кл.слова (ненормированные):
environmental stress -- excitation pressure -- Pinus sylvestris -- Siberia -- xanthophyll cycle
Аннотация: Regeneration patterns of Pinus sylvestris L. juveniles in central Siberian glades were studied in relation to cold-induced photoinhibition. Spatial distribution of seedlings in different height classes revealed higher seedling densities beneath the canopy than beyond the canopy, and significantly higher densities of seedlings < 50 cm tall on the north side of the trees. These patterns coincided with differences in light conditions. Compared with plants on the north side of canopy trees (north-exposed), photosynthetic photon flux (PPF) received by plants on the south side of canopy trees (south-exposed) was always higher, making south-exposed plants more susceptible to photoinhibition, especially on cool mornings. Chlorophyll fluorescence data revealed lower photochemical efficiency and increased non-photochemical quenching of small (20-50 cm in height), south-exposed seedlings from spring to early autumn, indicating increased excitation pressure on photosynthesis. Maximum rate of oxygen evolution was less in south-exposed plants than in north-exposed plants. Increased pools of xanthophyll cycle pigments and formation of the photoprotective zeaxanthin provided further evidence for the higher susceptibility to photoinhibition of south-exposed seedlings. A linear mixed model analysis explained many of the physiological differences observed in seedlings according to height class and aspect with early morning temperature and PPF as predictors. The link between photoinhibition and differential distribution of seedlings by height class suggests that photoinhibition, together with other environmental stresses, decreases the survival of small, south-exposed P sylvestris seedlings, thereby significantly affecting the regeneration pattern of central Siberian pine glades.
Полный текст,
WOS,
Scopus
Держатели документа:
Univ Wageningen & Res Ctr, Forest Ecol & Forest Management Grp, NL-6700 AH Wageningen, Netherlands
Princeton Univ, Dept Ecol & Evolutionary Biol, Princeton, NJ 08544 USA
Russian Acad Sci, Inst Forest, Siberian Branch, Krasnoyarsk 660036, Russia
Max Planck Inst Biogeochem, D-07745 Jena, Germany
Доп.точки доступа:
Slot, M...; Wirth, C...; Schumacher, J...; Mohren, GMJ; Shibistova, O...; Lloyd, J...; Ensminger, I...