2006
Holeksa, J.; Barć, A.; Hyla, A.; Krawczyk, B.
Changes in coarse woody debris of a West Carpathian subalpine spruce forest over ten years Journal Article
In: Polish Botanical Studies, vol. 22, pp. 231-240, 2006, ISSN: 08670730, (3).
@article{2-s2.0-38349001036,
title = {Changes in coarse woody debris of a West Carpathian subalpine spruce forest over ten years},
author = { J. Holeksa and A. Barć and A. Hyla and B. Krawczyk},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-38349001036&partnerID=40&md5=e82a2c917f03a16d94776def640417a3},
issn = {08670730},
year = {2006},
date = {2006-01-01},
journal = {Polish Botanical Studies},
volume = {22},
pages = {231-240},
abstract = {Changes in the amount and structure of coarse woody debris (CWD) from 1993 to 2003 as well as the characteristics and spatial distribution of trees that died during two periods (1986-1993; 1996-2003) were studied in a large tract (14.4 ha) of West Carpathian subalpine spruce forest. All dead trees, both snags and logs, were measured and mapped in 1993 and 2003. The amount of CWD increased by 11% in respect of number of dead trees (from 201 to 224 trees h-1) and by 29% in respect of volume (from 133 to 172 m3 ha-1) during 10 years. Thus the input of snags and logs was not balanced by the recent disappearance of old ones. The rate of tree decay expressed as number of trees dropped in recent decades from 4.2 trees ha-1 year-1 before 1993 to 3.1 trees ha-1 year-1 after 1993. The size of dying trees increased considerably, however, and the rate of tree decay expressed as volume increased from 3.7 m3 ha-1 year-1 before 1993 to 5.1 m3 ha-1 yea-1 after 1993. In both periods, most trees died standing and the fewest were uprooted. Before 1993, thinning intensity was highest among thin trees and lowest among trees of average dimensions. After 1993, thinning intensity was similar for all diameter classes. Spruces that died both before and after 1993 were distributed in clumps, but the spatial relations between trees that died standing and were broken or uprooted changed. Snags and logs of trees that died in 1986-1993 were randomly mixed, whereas those appearing after 1993 were strongly associated spatially. The shift in the mortality pattern reflects a shift in causal factors of tree death: from competition for light to wind and insect pests. These changes accompanied a gradual decrease in stand density.},
note = {3},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Changes in the amount and structure of coarse woody debris (CWD) from 1993 to 2003 as well as the characteristics and spatial distribution of trees that died during two periods (1986-1993; 1996-2003) were studied in a large tract (14.4 ha) of West Carpathian subalpine spruce forest. All dead trees, both snags and logs, were measured and mapped in 1993 and 2003. The amount of CWD increased by 11% in respect of number of dead trees (from 201 to 224 trees h-1) and by 29% in respect of volume (from 133 to 172 m3 ha-1) during 10 years. Thus the input of snags and logs was not balanced by the recent disappearance of old ones. The rate of tree decay expressed as number of trees dropped in recent decades from 4.2 trees ha-1 year-1 before 1993 to 3.1 trees ha-1 year-1 after 1993. The size of dying trees increased considerably, however, and the rate of tree decay expressed as volume increased from 3.7 m3 ha-1 year-1 before 1993 to 5.1 m3 ha-1 yea-1 after 1993. In both periods, most trees died standing and the fewest were uprooted. Before 1993, thinning intensity was highest among thin trees and lowest among trees of average dimensions. After 1993, thinning intensity was similar for all diameter classes. Spruces that died both before and after 1993 were distributed in clumps, but the spatial relations between trees that died standing and were broken or uprooted changed. Snags and logs of trees that died in 1986-1993 were randomly mixed, whereas those appearing after 1993 were strongly associated spatially. The shift in the mortality pattern reflects a shift in causal factors of tree death: from competition for light to wind and insect pests. These changes accompanied a gradual decrease in stand density.
2005
Holeksa, J.; Woźniak, G.
In: Phytocoenologia, vol. 35, no. 1, pp. 1-18, 2005, ISSN: 0340269X, (25).
@article{2-s2.0-33646105161,
title = {Biased vegetation patterns and detection of vegetation changes using phytosociological databases. A case study in the forests of the Babia Góra National Park (the West Carpathians, Poland)},
author = { J. Holeksa and G. Woźniak},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-33646105161&doi=10.1127%2f0340-269X%2f2005%2f0035-0001&partnerID=40&md5=5491f5ee75352ea9efac720d97904717},
doi = {10.1127/0340-269X/2005/0035-0001},
issn = {0340269X},
year = {2005},
date = {2005-01-01},
journal = {Phytocoenologia},
volume = {35},
number = {1},
pages = {1-18},
publisher = {Gebruder Borntraeger Verlagsbuchhandlung},
abstract = {A huge number of phytosociological relevés, which have been collected in Europe during the last century, seems to be a useful point of reference for analyses of temporal changes in vegetation. The high degree of subjectivity during data collection, however, makes difficult the comparison between data sets collected at different time by different authors. Being aware of this we attempted to reveal 30-year changes in strictly protected old-growth mountain forests. We compared two sets of relevés: A subjective phytosociological sample collected in the 60s and a systematic random one from the 90s of the XX century. Standard phytosociological data gave distinct vegetation units with transitional patches poorly represented. This was observed both in the gradient between beech and coniferous forests in the montane belt and in the altitudinal gradient including two forests belts. On the contrary, the random sample did not indicate discontinuity in any of these gradients. We suggest that in spite of better representation of rare plant communities, in the subjective sample a considerable part of vegetation variability was omitted to emphasize differences between associations. Most species positively distinguishing syntaxa were more frequent in the subjective sample because of preferential sampling in patches with a high number of such species. There were few diagnostic species with higher frequency in the random sample or with similar frequencies in both samples. Such results were interpreted as an evidence of spreading of these species. Comparisons between samples revealed the expansion of heliophilous species typical for communities of Betulo-Adenostyletea and dramatic regeneration decline of Abies alba, Acer pseudoplatanus and Picea abies. © 2005 Gebrüder Borntraeger.},
note = {25},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
A huge number of phytosociological relevés, which have been collected in Europe during the last century, seems to be a useful point of reference for analyses of temporal changes in vegetation. The high degree of subjectivity during data collection, however, makes difficult the comparison between data sets collected at different time by different authors. Being aware of this we attempted to reveal 30-year changes in strictly protected old-growth mountain forests. We compared two sets of relevés: A subjective phytosociological sample collected in the 60s and a systematic random one from the 90s of the XX century. Standard phytosociological data gave distinct vegetation units with transitional patches poorly represented. This was observed both in the gradient between beech and coniferous forests in the montane belt and in the altitudinal gradient including two forests belts. On the contrary, the random sample did not indicate discontinuity in any of these gradients. We suggest that in spite of better representation of rare plant communities, in the subjective sample a considerable part of vegetation variability was omitted to emphasize differences between associations. Most species positively distinguishing syntaxa were more frequent in the subjective sample because of preferential sampling in patches with a high number of such species. There were few diagnostic species with higher frequency in the random sample or with similar frequencies in both samples. Such results were interpreted as an evidence of spreading of these species. Comparisons between samples revealed the expansion of heliophilous species typical for communities of Betulo-Adenostyletea and dramatic regeneration decline of Abies alba, Acer pseudoplatanus and Picea abies. © 2005 Gebrüder Borntraeger.