An interdisciplinary approach has been developed for a comprehensive study of the restoration (increase) of the tree-line border. In essence, the approach is a detailed scheme in eleven steps, which can have universal application in the study of processes in the tree-line border in all mountains in ...

The Macedonain pine (Pinus peuce Griseb.) is one of the main species in the subalpine forests on the Balkan Peninsula. Given the forecasted increase of temperatures in the next decades there are worries about the health status and distribution of many species, including the currently dominant...

Kniazevska kultura is among the oldest large-scale plantations (1893) in Bulgaria. It provides the opportunity to analyze the long-term growth of local and introduced coniferous tree species and use the conclusions to select optimal species for future plantings. Our results show consistent good...

Review has been made of forest-biological and climatic investigations in ecological stations of the Forest Research institute, BAS, in Rila and Stara planina Mts., which are included in the European network of stations for long-period investigations in forest ecosystems and landscapes of EU...

The coefficients of accumulation of certain macro- and microelements in Abies alba have been determined. Soil conditions were Rendzinas - soil without exchangeable acidity and Dystric Cambisols - soil with exchangeable acidity. The coefficients have been calculated using exchangeable forms of...

On the northwestern slopes of the Rila Mountain 17 representative Norway spruce trees were investigated by dendrochronological analysis. A chronology of the radial growth in millimeters and indices for the period 1915-2000 within a range of 85 years was established. During the period of...

A chronology of the radial growth in millimeters is build up and indexes for the common beach (Fagus sylvatica L.) with length of the row up to 178 years in Berkovitsa Balkan Mountain are determined. The periods of increased and reduced growth are determined. For the period 1824-2002 three cycles...

This climatological study deals with a preliminary assessment on the radiation regime in the region of Sakar. The meteorological information for the district concerns an 11-years period (1980-1990). The annual course and space distribution of air temperature, total and effective solar radiation as...

Twelve trees of both Pinus silvestris L. and Pinus nigra Arold from the region of the "Borino Forestry Station in the West Rhodopes have been tested. The cultivations are situated at a distance of about 2 km apart and though some of the components of the ecological conditions are similar, the two...

Multiple-regression analysis was applied to determine the effect of 25 factors on the radial increment of sample trees of Pinus sylvestris over the period 1888-1987. The trees were in a stand about 100 years old at 1400-1500 m altitude in Bulgaria. A mean chronology was established, and the...