Metoda modelowania potencjalnych zdolności produkcyjnych świerka w górach
AbstractThe aim of the research was to develop a statistical model describing the potential productivity of Norway spruce in the West Beskid Mountains (Beskidy Zachodnie; southwestern Poland). The research used the experimental material coming from 387 sample plots located in the West Beskid Mts. and the data from a stem analysis of 95 spruces. The first stage of the study was to develop a systematic-error-free system of site index curves. The local system of site index curves worked out using the stem analysis data was then employed to calculate the site indices for spruces from specific sample plots. At the next stage, a regression model, called a geocentric model, was developed. This model describes the site index of stands as a function of variables characterising the topography of the terrain (height above sea level, exposure, slope, size of the mountain massif, topographical indices) and the type of soil parent rock (12 main types were identified in the research area). It was found that height above sea level is the variable which explains the largest portion (around 60%) of the variability of the site index of spruce stands. The highest recorded site index, approximating 45 m, was noted for the range between 600 and 750 m a.s.l. The value of the index gradually decreases with the increasing altitude, by ca. 3.41 m on average per 100 m increase in height a.s.l. The site index shows also a clear correlation with the type of soil parent rock. Compared to spruces growing on the Lower Godula beds, those from the Lackie beds reach a 5.4 m on average higher site index, followed by spruces from the Magura beds (+4.69 m), colluvial beds (+4.21 m), sub-Magura beds (+4.21 m), biotite beds (+4.08 m), hieroglyphic sandstones (+3.45 m), Ropianka beds (+3.33 m), Pasierbiec sandstones (+3.08 m), Upper Istebna sandstones (+2.87 m), Upper Godula beds (+1.74 m), and Lower Istebna beds (+ 1.14 m). The potential productivity of Norway spruce depends also on exposure, slope, size of the mountain massif, and situation of the plot on the slope. The relationship between the site index and the environmental factors can be used to assess the precision of site index models and to make provisional corrections to the models. If the site index of stands remains correlated with their age after removal of the known environmental factors, this suggests that the models are ill-fitted to the local conditions. Based on this, it is possible to correct the course of site index curves in such a way as to mirror the local pattern of the height growth of stands. Geocentric site index models may be used in forest management when defining its future directions, especially when taking decisions on the species composition of stands. Besides, models of this type can be applied in forest inventory, and in analyses concerning carbon sequestration in mountain areas. They would also be used as a tool (with some modifications to explanatory variables) for forecasting the effect of climatic changes on the productivity of stands in mountains.
|Other language title versions||A method for modelling the potential productivity of Norway spruce in mountains|
|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||7.5|
|Citation count*||7 (2016-04-12)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.