TY - JOUR AU - V.G. Onipchenko AU - O.V. Blinkova AU - A.A. Zakharov AU - M.A. Abzeeva PY - 2001/12/01 Y2 - 2024/03/28 TI - Dynamics of two contrasted alpine communities in the Causasus: resuffs of 14-years permanent plot observations JF - Oecologia Montana JA - OM VL - 10 IS - 1-2 SE - Standard articles DO - UR - http://om.vuvb.uniza.sk/index.php/OM/article/view/125 AB - Fluctuation and successional dynamics were studied in alpine lichen heath (ALH, winter snow free community) and snowbed community (SBC) in the Teberda Reserve, the Northwest Caucasus. Shoot numbers of each species were counted on 80 permanent plots for 14 years. Mean temporal variation coefficients were significantly bigger for generative shoot numbers than for total shoot numbers in both communities. All studied ALH species had coefficients of variation for total shoot number of less than 60%, but 5 of 20 species in SBC exceeded this value. A significant positive correlation coefficient was obtained between spatial and temporal variation for combined data and for total shoot numbers in SBC. As a whole, dominants were more stable than less abundant species in both communities. Most of the species in SBC showed positive correlations with each other (Festuca ovina, Carum meifolium, Pedicularis nordmanniana, Luzula multiflora, Anthoxanthum odoratum, Corydalis conorhiza, Gentiana pyrenaica, Festuca brunnescens, Phleum alpinum). Several species of ALH and SBC showed a significant linear trend for the period of observation. A positive trend (significant increase of shoot number) was found in 8 species in SBC, but Catabrosella variegata demonstrated a significant decrease in population density. Many fewer (5 from 19 studied species) ALH species showed an increase in shoot numbers. Only Trifolium polyphyllum decreased population density in ALH. Increased abundance of meadow species may be connected with global climatic changes or with a long-term response to the ending of grazing. According to autocorrelation analysis all species can be divided into two groups. The first group (most of the species in both communities) included species without any significant correlation coefficient for all temporal lags. The other group included species that had significant positive correlation coefficients for lag 1 year. More species from SBC demonstrated such conservative dynamics. ER -