2007
Semi-dry grasslands along a climatic gradient across Central Europe: Vegetation classification with validation
ILLYÉS, Eszter, Milan CHYTRÝ, Zoltán BOTTA-DUKÁT, Ute JANDT, Monika JANIŠOVÁ et. al.Základní údaje
Originální název
Semi-dry grasslands along a climatic gradient across Central Europe: Vegetation classification with validation
Název česky
Semi-dry grasslands along a climatic gradient across Central Europe: Vegetation classification with validation
Autoři
ILLYÉS, Eszter (348 Maďarsko), Milan CHYTRÝ (203 Česká republika, garant), Zoltán BOTTA-DUKÁT (348 Maďarsko), Ute JANDT (276 Německo), Monika JANIŠOVÁ (703 Slovensko), Iveta ŠKODOVÁ (703 Slovensko), Wolfgang WILLNER (40 Rakousko) a Ondřej HÁJEK (203 Česká republika)
Vydání
Journal of Vegetation Science, Uppsala, Opulus Press, 2007, 1100-9233
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10600 1.6 Biological sciences
Stát vydavatele
Švédsko
Utajení
není předmětem státního či obchodního tajemství
Odkazy
Impakt faktor
Impact factor: 2.251
Kód RIV
RIV/00216224:14310/07:00020869
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000250089400008
Klíčová slova anglicky
Austria; Bromion; Cirsio-Brachypodion; Czech Republic; Germany; Hungary; Phytosociology; Romania; Slovakia; Training and test data sets; Vegetation database
Štítky
Příznaky
Mezinárodní význam, Recenzováno
Změněno: 30. 1. 2008 18:23, prof. RNDr. Milan Chytrý, Ph.D.
V originále
Question: What is the variation in species composition of Central European semi-dry grasslands? Can we apply a training-and-test validation approach for identifying phytosociological associations which are floristically well defined in a broad geographic comparison; can we separate them from earlier described associations with only a local validity? Location: A 1200 km long transect running along a gradient of increasing continentality from central Germany via Czech Republic, Slovakia, NE Austria, Hungary to NW Romania. Methods: Relevés with > 25% cover of Brachypodium pinnatum and/or Bromus erectus were geographically selected from a larger database. They were randomly split into two data sets, TRAINING and TEST, each with 422 relevés. Cluster analysis was performed for each data set on scores from significant principal coordinates. Different partitions of the TRAINING data set were validated on the TEST data set, using a new method based on the comparison of % frequencies of species occurrence in clusters. Clusters were characterized by statistically defined groups of diagnostic species and values of climatic variables. Results: Species composition changed along the NW-SE gradient and valid clusters were geographically well separated. Optimal partition level was at 11 clusters, six being valid: two clusters Germany and the Czech Republic corresponded to the Bromion erecti; two clusters from the Czech Republic and Hungary to the Cirsio-Brachypodion, and two clusters were transitional between these two alliances. Conclusion: The training-and-test validation method used in this paper proved to be efficient for discriminating between robust clusters, which are appropriate candidates for inclusion in the national or regional syntaxonomic overviews, and weak clusters, which are specific to the particular classification of the given data set.
Česky
Byla popsána diverzita trávníků s dominancí druhů Brachypodium pinnatum a Bromus erectus ve střední Evropě. Současně byla testována nová metoda validace klasifikace vegetace vytvořené pomocí shlukové analýzy.
Návaznosti
GA206/05/0020, projekt VaV |
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MSM0021622416, záměr |
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