RESUMEN
Water use efficiency (WUE) of five dominant tree species (Pinus koraiensis, Fraxinus mandshurica, Acer mono, Quercus mongolica, and Tilia amurensis) was estimated using the stable carbon isotope method in a broadleaved Korean pine forest in Changbai Mountains. Leaf carbon (C), nitrogen (N), and phosphorus (P) contents were measured to analyze nutrient utilization of the dominant species. The relationship between WUE and leaf nutrient contents was systematically assessed. WUE was different due to the variations of micrometeorological factors at different locations in the canopy. The four broadleaved tree species showed upper layer > middle layer > lower layer, while P. koraiensis showed upper layer > lower layer > middle layer. WUE of evergreen coniferous P. koraiensis was higher than that of two broadleaved species with diffuse-porous wood (T. amurensis and A. mono) and lower than that of two broadleaved species with ring-porous wood (F. mandshurica and Q. mongolica). The compound-leaved species (F. mandshurica) had the highest WUE. The WUE of new leaves was significantly higher than old leaves in P. koraiensis. The carbon content and C/N of the old and new leaves of evergreen coniferous P. koraiensis were significantly higher than those of the other four broadleaved tree species, while nitrogen content and N/P were significantly lower than those of the four broadleaved tree species. P content of old leaves of P. koraiensis was significantly lower than that of the four broadleaved tree species. P content of new leaves of current year was not significantly different from that of the broadleaved tree species. The WUE of five tree species had a poor correlation with leaf C content, but a positive correlation with leaf N content. The WUE of evergreen coniferous and deciduous broadleaved tree species was correlated with leaf P content but in opposite direction.
Asunto(s)
Pinus , Árboles , China , Bosques , Nutrientes , Hojas de la Planta , República de Corea , AguaRESUMEN
Water use efficiency (WUE) is an objective indicator of plant water use, the research of which is helpful to understand the carbon-water coupling mechanism in terrestrial ecosystems. We investigated WUE of dominant tree species in the succession series of broad-leaved Korean pine forests in Changbai Mountain (middle-aged poplar-birch secondary forest, mature poplar-birch secondary forest, broad-leaved Korean pine forest) by using stable carbon isotope technology. The WUE of three forests under different succession stages decreased in order of broad-leaved Korean pine forest > middle-aged poplar-birch secondary forest > mature poplar-birch secondary forest. In addition, the same tree species had different WUE in different forest stands. The WUE of Populus davidiana and Betula platyphylla in the middle-aged poplar-birch secondary forest was higher than that in mature poplar-birch secondary forest. The WUE of Fraxinus mandshurica in broad-leaved Korean pine forest was much higher than that in middle-aged poplar-birch secondary forest. The WUE of Acer mono and Quercus mongolica in broad-leaved Korean pine forest was higher than that in mature poplar-birch secondary forest. The dominant tree species had different WUE as for wood types which generally presented ring-porous wood species>diffuse-porous wood species. There were different seasonal trends during the growing season among the dominant species in the broad-leaved Korean pine forest. The WUE of Fraxinus mandshurica, Acer mono, Quercus mongolica and Tilia amurensis showed first decreasing and then increasing, while that of Pinus koraiensis was opposite. The WUE of the broad-leaved Korean pine forest was negatively correlated with temperature in the growing season. The different WUE was one of the strategies for dominant species in the broad-leaved Korean pine forest in Changbai Mountains to adapt to the community succession and respond to climate and environmental change.
