Uwarunkowania przyrostu radialnego wybranych gatunków drzew z Wyżyny Kieleckiej w świetle analiz dendroklimatologicznych
AbstractThe study provides a characterisation of the short-term tree-ring growth behaviour of four forest tree species: silver fir (Abies alba Mill. — ABAL), Scots pine (Pines sylvestris L. — PISY), Norway spruce (Picea abies L. Karst. — PCAB) and European larch (Larbc decidua Mill. — LADE) on the Kielecka Upland, and attempts at defining its determinants. The research covered 80 subpopulations (sites) of those species (20 per species) selected from 80-100-year-old stands growing under various soil and climatic conditions. On each site, increment cores were sampled from 25-30 trees belonging to the highest classes of Kraft (one per tree), from the southern sector of trunk, at a height of 1.3 m above ground level. The widths of annual tree-rings were measured at the same height. The short-term annual ring growth responses of trees in the years 1951-2001 were characterised using two indicators: yearly sensitivity and yearly frequency. The former describes the relative year-to-year change in tree-ring widths (radial growth dynamics), the latter shows the relative number of trees which increased their ring widths in a given year compared to a previous year (radial growth frequency). In the first part of the work, the radial growth behaviour of the subpopulations of four tree species was characterised on the basis of yearly sensitivity series, and the causative factors were searched for. The second part of the work investigated the sensitivity and frequency chronologies constructed for each of the tree subpopulations. The main factors considered as a causal explanation of particular radial growth responses were three climatic elements, i.e. air temperature, precipitation and sunshine; also air pollution and other random events were taken into account. The short-term radial growth responses of trees were species-specific and mainly depended on the climatic factor. The differentiation in the short-term radial growth rhythm among the species appeared to be higher that the spatial variation within a given species. Sensitivity series and sensitivity and frequency chronologies proved to be efficient means for highlighting the species-specific radial growth features, and for identifying the factors that contributed to the tree-ring growth responses described by those series. In this way, the sensitivity of trees of the four species to the three climatic elements was shown. An analysis of one subpopulation for each species revealed that it exhibited most of the climate-radial growth relationships characteristic of the whole population in the Kielecka Upland region. However, due to the high spatial variability of these relationships, such studies should be extended to a greater number of subpopulations. The data on the above relationships were obtained on the basis of a set of regional chronologies for each species. Then, an attempt was made to identify the tree species of individual subpopulations. Because of the high variability in radial growth rhythm between subpopulations, both the correlation coefficient and the convergence coefficient appeared to be ineffective in deciding whether a given tree series should be included in the site chronology, and a site chronology in the regional chronology; they did not allow a reliable identification of tree species on the basis of their site series and chronologies, either. In the two former cases, the coefficients of correlation and convergence between series and a site chronology, and between site chronologies and a regional chronology proved to be a more effective tool. In the latter case, cluster analysis was the most efficient way of species identification. When identifying trees on the basis of their sensitivity series, it was necessary to consider many (20) trees originating from various sites. Similarly, when identifying tree species of a given subpopulation on the basis of its chronology of sensitivity or frequency, the regional set of either chronology should have consisted of at least 10 site chronologies built of at least 20 series and aged 50 or more years. A great similarity in the site chronologies of a given species and those of its frequency made it possible to construct regional chronologies of both kinds for the tree species studied. The latter chronologies constituted regional standards that described qualitatively and quantitatively the radial growth responses of trees of those species in the Kielecka Upland region, and did not contain any local, random deviation of some trees or whole populations from the general pattern. A high similarity in the site chronologies of sensitivity or frequency between subpopulations within a species provided evidence to suggest that the trees of a given species exhibit a very similar radial growth rhythm in the region. In turn, a relatively high similarity in the regional chronologies of species indicated that there exist some factors that have a similar influence on the radial growth behaviour of trees from different species. The latter chronologies were then used to develop regional models of climate—radial growth relationships for individual species, using correlation and multiple regression (response function) methods. In order to test the dendroclimatic quality and representativeness of site chronologies, three important indicators were calculated, such as mean coefficient of correlation between sensitivity series (rme„,), Expressed Population Signal (EPS) and Signal-to-Noise Ratio (SNR), and the pattern of site chronologies was compared with that of the regional chronology. It was found that achieving high values of the indicators for subpopulations did not necessarily imply that all significant relationships between climate and radial growth, typical of a given tree species in the region, would be established. The regional chronologies of individual species formed a basis for constructing a multi-species chronology. The course of the latter, however, appeared to he dominated by fir, pine and spruce, making it necessary to validate the climate—growth relationships obtained on its basis by contrasting them with the results from individual species chronologies. Of the tree species studied on the Kielecka Upland, spruce and fir showed the most uniform short-term responses of radial growth both within and among subpopulations in the period 1951-2001. Pine was poorest in either respect. Larch behaved uniformly within subpopulations, but not in the whole region. The results indicate that the radial growth of fir and spruce is more sensitive to environmental factors, including climate. This was also confirmed by the largest number of signature years in the two species. Direct correlation and multiple regression (response function) analyses of the climate-radial growth relationships showed that pine and larch are highly sensitive to the climatic factor as well. Fir displayed highest sensitivity to air temperature and lowest to precipitation. Pine, being also highly sensitive to temperature, showed lowest sensitivity to sunshine. By contrast, sunshine and precipitation were the most important factors affecting the radial growth of larch, whereas air temperature had the smallest influence. While the responses of the subpopulations of the three species were highly stable, the subpopulations of spruce showed the widest spatial variability, the proportions of those with highest sensitivity to temperature, precipitation or sunshine being similar. Air temperature in the months of the year in which a tree-ring was formed did not differ from that in the previous year in the effect on the radial growth behaviour of the four tree species. For precipitation, the same was true in the case of pine and larch, whereas the growth responses of spruce were more affected by current than previous year's values. Fir showed an opposite pattern. The effect of previous year's sunshine was much stronger than that of sunshine in the year of tree-ring formation for all the species. Subpopulations of the four tree species usually showed significant negative relationships to the air temperature and sunshine of previous year's September, and for spruce and larch also to precipitation of the same month. Almost all subpopulations exhibited positive relationships with the temperature of March and February (except larch), and many of those with the precipitation of June and July of the year of tree-ring formation. The radial growth responses of all the species were the most strongly determined by the air temperature of current year's March. As follows from an analysis of the principal components of site chronologies, the climatic elements that had similar effects on the radial growth behaviour of trees in the four species were the air temperature of March, June and September and the precipitation and sunshine of September of the previous year, and the air temperature of February and March and the precipitation of June of the year of tree-ring formation. Hence, the factor deciding about a similarity in the radial growth rhythm between trees of the species studied was composed of numerous meteorological elements from various seasons of the two years. Similarly, species chronologies were affected by such meteorological elements as the air temperature, precipitation and sunshine of spring and the precipitation of September of the year preceding the formation of a tree-ring as well as the temperature of February, the temperature and sunshine of August, and the precipitation of September of the current year. The results obtained by statistical methods were confirmed by an analysis of climatic conditions in signature years. A massive increase in the radial increment of trees was noted in cases where a previous year had a cold long winter and cool wet cloudy summer and autumn, and a current year had a warm short winter, a sunny dry spring and a wet summer. Apart from signature years, there were very frequent years in which trees showed a low uniformity of radial growth responses accompanied by a low mean dynamics of radial growth. This may be attributed to the average weather conditions occurring in seasons important for the radial growth of trees, among other things. The universality of the yearly sensitivity indicator, used in the work, lies in the fact that it can easily be calculated on the basis of tree-ring width series or chronologies. In this way, one always obtains an identical series or chronology of sensitivity, which makes it possible to conduct more objective comparative studies. Yearly sensitivity may be used for both analysing climate-radial growth responses and determining signature years. The regional chronologies of sensitivity and frequency for four tree species and the regional multi-species chronologies provided a basis for constructing a dendrochronological calendar for the Kielecka Upland. By applying the calendar, it was possible to track the changes that occurred in the similarity of the radial growth behaviour of trees in various species over the years under the influence of various environmental factors, especially the climatic factor.
|Other language title versions||Determinants of radial growth in some tree species on Kielecka Upland in light of dendroclimatological analyses|
|Publisher||Uniwersytet Rolniczy im. Hugona Kołłątaja w Krakowie, MNiSW |
|Publishing place (Publisher address)||Kraków|
|Book series /Journal (in case of Journal special issue)||Zeszyty Naukowe Uniwersytetu Rolniczego im. Hugona Kołłątaja w Krakowie. Rozprawy, ISSN 1899-3486, (0 pkt)|
|Publication size in sheets||13|
|Score||= 25.0, 27-07-2017, BookNotMainLanguagesAuthor|
|Citation count*||12 (2015-11-16)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.