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Shoot morphology and leaf gas exchange of Fagus sylvatica as a function of light in Slovenian natural beech forests

100%

Cater M.

Dendrobiology

2010

tom 64

Five plots with young beech trees of the same age (13–15 years) were established to study the threshold, where plagiotropic growth becomes evident as the consequence of the reduced light intensity. Trees were equally distributed along the light gradient and were divided according to light conditions (Indirect Site Factor, ISF) into three groups of stand conditions: close canopy stand (ISF<20), edge (2025). Morphological and physiological responses of young beech were studied between managed and old growth forest and between different forest complexes (Pohorje and Kocevje region) on natural beech sites. Criteria for the plagiotrophic growth was the relation between tree length and tree height (l/h) under various light conditions. Under controlled conditions (temperature, flow and CO2 concentration, RH, light intensity) light saturation curves of leaf net photosynthesis were measured on same trees to compare both responses between different light categories and different plots within comparable light conditions. Our study confirmed different thresholds for morphologic response between two forest complexes as well as between old growth and managed forest. Results were in accordance with physiological responses: the value of limiting light for a plagiotropic response was lower in Kocevje (17% ISF) than on Pohorje (25% ISF).

A 13-year change in ground-layer vegetation of Carpathian beech forests

80%

Lysik M.

Polish Journal of Ecology

2009

tom 57

nr 1

47-61

13 year changes in the ground vegetation of natural beech forest were studied in the Babia Góra National Park (South Poland) and compared with the results of similar study in the Ojców National Park published previously (Łysik 2008). In 1-ha permanent research plot homogeneous vegetation patches of the size at least 1m², that differed from neighbouring patches in species composition and/or species share (patch types) were specified and mapped. After intersecting two (for years 1991 and 2004) numerical maps a synthetic map, used then as a basis for evaluating the ground vegetation changes, was created. Changes in each patch and dynamics of each species were derived using adequate formulas. Shannon-Wiener and evenness indices were measured for both years. Comparison of species composition and structure of the herb layer in 1991 and 2004 gives evidence of a highly dynamic nature of the ground layer. On 27% of investigated area vegetation were totally different than 13 years before, while less than 3% of the study area stayed unchanged. On the rest of the area changes of diverse intensity occurred. However, the mean over-plot intensity of changes was about 65% (calculated according to formula 1). Plant cover decreased by about 20%, but at the same time increases were noticed in species number and patch types. There was a significant increase in the area covered by grasses and ferns at the expense of Rubus idaeus L., which used to be a dominant species in 1991. Moreover, cover share of all species become more evenly distributed in comparison with situation 13 years before (evenness index increased from 0.49 to 0.68). The most dynamic species were those associated with decaying stumps and downed logs. These results suggest that, in natural beech forests, overstory dynamics or other mechanisms (like competition with natural recruitment of trees) make the dominance of any species in ground-layer not longer than a decade.

Ograniczanie wyników

1 Dendrobiology

1 Polish Journal of Ecology

1 Cater M.

1 Lysik M.

1 2010

1 2009

Wyniki wyszukiwania

Shoot morphology and leaf gas exchange of Fagus sylvatica as a function of light in Slovenian natural beech forests

A 13-year change in ground-layer vegetation of Carpathian beech forests