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Adaptative strategy of leaf traits to drought conditions: Quercus aliena var. acuteserrata forest (The Qinling Mts. China)

100%

Wang M., Wan P., Chai Y., Guo Y., Zhang X., Yue M.

Polish Journal of Ecology

2015

tom 63

nr 1

In a climax community where all species are sharing relatively similar and stable habitat, there are differences in leaf traits between deciduous trees and shrubs and dominant species and companion species, especially in leaf lifespan (LLs). What are the differences of relationships among leaf traits between deciduous trees and shrubs? What are the mechanisms of this phenomenon? Here, we presented a one-year observation and recorded the LLs followed a modified method in a Quercus aliena var. acuteserrata forest in the north slope of the Qinling Mountains, China. We found that (i) Different species in the same stand performed quite differently in their LLs (P <0.005). Average LLs of shrubs was slightly longer (P = 0.05) than that of deciduous trees. (ii) LLs showed a significant negative correlation with specific leaf area (SLA) and leaf nitrogen content (LNC) (P <0.05) in deciduous trees, however, a significant positive correlation with LNC and leaf carbon content (LCC) (P <0.05) was detected in shrubs. (iii) The comparison of the traits between dominant and companion species in arbor layer and shrub layer showed that there was no significant difference in LLs, LCC and LNC, except SLA in arbor layer. Our study indicated that the amount of light, at the community scale, might be a main factor determining the LLs of wood plants in deciduous forest. The difference between trees and shrubs in relationships among leaf traits suggests that deciduous trees and shrubs may take different strategies to adapt to the environment. SLA is likely to be a marker trait to distinguish dominant and companion species in arbor layer of deciduous broad leaved forest.

Forest patch dynamics initiated by disturbance: distribution pattern of Larix chinensis (Bessen) patches along the altitudinal gradient in relation to light and temperature conditions (Qinling Mts. China)

80%

Duan R.-Y., Huang M.-Y., Wang X.-A.

Polish Journal of Ecology

2013

tom 61

nr 2

According to the theory of forest growth cycle, forest communities are dynamic mosaic systems composed of patches in different development stages. On basis of measurement of the four patch types [gap phase (G), building phase (B), mature phase (M) and degenerate phase (D)], the distribution pattern of different patch types and heterogeneity of the light and temperature along an altitudinal gradient were analyzed. The study forests were located in Larix chinensis forests in the Taibai Natural Reserve, and the whole forest was divided into three transects, i.e. low altitude (2900–3000 m a.s.l.), middle altitude (3100–3200 m a.s.l.) and high altitude (3300–3400 m a.s.l.). The implications of environmental heterogeneity on species coexistence and maintenance of species diversity were discussed in this paper. Our results were as follows: (1) In different elevation gradient, the proportions of the four patch types were different. Compared with low elevation and high elevation, in middle elevation, the proportions of gap phase and building phase were obviously lower; while the proportions of mature phase and degenerate phase were noticeably higher. In different elevation gradient, the distribution pattern of the four patch types was changed to some extent. (2) The daily change patterns of light and temperature in different patch types in forest cycle were different. The light intensity was much greater in gap phase than in the other three phases. The light intensity and its amplitude of changes in different patch types followed the order of G>D>B≥M. Air temperature in different patch types followed the order of G>B>D≥M. The amplitude of diurnal temperature changes in air and soil surface followed the order of G>D>B>M. (3) With elevation increasing, light intensity, the biggest air temperature, biggest soil temperature and temperature difference in four patch phase increased significantly, and average air temperature and average soil temperature significantly decreased. The spatio-temporal heterogeneity of ecological factors in different patch types in forest cycle provided a basis to maintain the coexistence of different species with different characteristics within forest community.

Recruitment pattern of tree populations along an altitudinal gradient: Larix chinensis Beissn in Qinling Mountains [China]

80%

Duan R. Y., Wang X.-A., Tu Y.-B., Huang M.-Y., Wang C., Zhu Z.-H., Guo H.

Polish Journal of Ecology

2009

tom 57

nr 3

451-459

Larix chinensis Beissn is an endangered plant found only in the Qinling Mountains, Shaanxi, northwestern China. It is densely distributed in the alpine and subalpine belt on their highest peak Taibai Mountain. Age structure studies along a montane altitudinal gradient would be helpful in understanding the limiting factors on the regeneration of natural forests. The forest was divided into three transects, i.e., lower limit (2900–3000 m), mid-altitude (3100–3200 m) and upper limit (3300–3400 m). The age structures differed across altitude classes. The age structure in the low altitude transect was closed to bell-shaped and characterized by the dominance of adult trees. A reverse-J shape age structure was found in the mid-altitude transect. Multi-modal age distribution was found in the high altitude transect, and was caused by lack of young seedlings and saplings. This suggests that different limiting factors play important roles in shaping the age structure and forest regeneration at different altitudes. In the low altitude, light availability was probably the most important limiting factor. In the mid-altitudinal transect, density dependent intraspecific competition between trees likely controlled regeneration of L. chinensis. We suggest that limiting climatic factors, e.g. temperature, play an important role in determining the age structure of L. chinensis populations in highaltitude areas.

Ograniczanie wyników

3 Polish Journal of Ecology

2 Huang M.-Y.

2 Wang X.-A.

1 Chai Y.

1 Duan R. Y.

1 Duan R.-Y.

1 Guo H.

1 Guo Y.

1 Tu Y.-B.

1 Wan P.

1 Wang C.

1 Wang M.

1 Yue M.

1 Zhang X.

1 Zhu Z.-H.

1 2015

1 2013

1 2009

Wyniki wyszukiwania

Adaptative strategy of leaf traits to drought conditions: Quercus aliena var. acuteserrata forest (The Qinling Mts. China)

Forest patch dynamics initiated by disturbance: distribution pattern of Larix chinensis (Bessen) patches along the altitudinal gradient in relation to light and temperature conditions (Qinling Mts. China)

Recruitment pattern of tree populations along an altitudinal gradient: Larix chinensis Beissn in Qinling Mountains [China]