Growth patterns of Scots pine (Pinus sylvestris L.) under the current regional pollution load in Lithuania

IF (2014): 1.269The hypothesis that trees have grown more rapidly in recent years as a consequence of climate warming and the reduced pollution was tested in Scots pine (Pinus sylvestris L.) forests in Lithuania. A hundred of the largest, dominant pine trees, with a diameter at breast height exceeding 50 cm, were selected in three experimental, over-mature stands located in different parts of the country (north-eastern, western and sea coast). Results confirmed that the annual increment of the trees analyzed has increased since 1980. The causes of such faster growth were higher air temperatures during the winter and, to a lesser extent, higher temperatures from May through August. The effect of precipitation was negligible. Using data on acidifying pollutants collected in last 30 years, a significant effect of the reduced SO2 concentration and sulphur deposition, as well as of the increased ammonia deposition, on the enhanced annual increment in the tree basal area was detected. Multiple regression analysis revealed that meteorological parameters can explain up to 50% of the observed variation in the increase of growth rate for Scots pine in Lithuania, while the variation in the concentration of acidifying pollutants accounted for an additional 30%. However, the pollution data set did not cover a timespan long enough (20-30 years) to clearly distinguish between the effect of the reduced pollution in recent years and the increased temperatures due to global warming as the driving factor of the enhanced growth observed for dominant pine trees in Lithanian forestsAplinkos tyrimų centrasAplinkotyros katedraValstybinis mokslinių tyrimų institutas Fizinių ir technologijos mokslų centrasVytauto Didžiojo universitetasŽemės ūkio akademij

N deposition, balance and benefit in the forest ecosystem of main landscape types of Lithuania

Sulphur emissions have declined in Europe by 67% since the early 1980s due to enactment of strict pollution control strategies, whereas nitrogen emissions have remained fairly constant. Consequently, the effect and benefits of nitrogen deposition remain among the most relevant ecological issues. The presented data reveal the trends of nitrate and ammonium concentrations in the air, their wet deposition and concentrations in soil water, ground and runoff water as well as the trends of different components of forest biota in areas where integrated monitoring stations have been operating since 1994. Data on nitrogen concentrations in the soil, ground and surface waters were analysed in relation to air nitrogen concentrations and their deposition. Changes in tree crown defoliation, and abundance, and diversity of the soil micro-arthropods, stream macro-invertebrates and small mammals were analysed in relation to concentrations of N compounds in studied substances in an effort to estimate N deposition benefits in forest ecosystems. N balance in areas studied revealed that the amount of nitrogen inflow into the system was very high in comparison with its elimination from the catchments. Approximately 1000 N kg/km(2) in LT01 and 600 N kg/km(2) in LT03 are accumulated in the investigated ecosystems per year. But, the relationship between condition of the conifers and air N compounds and their deposition was more significant than between N concentrations in soil and groundwater. N concentration in the studied substances resulted in more significant changes in abundance of soil micro-arthropods, stream macro-invertebrates and small mammals than in their diversityVytauto Didžiojo universitetasŽemės ūkio akademij

Present cement dust pollution still effects Scots pine (Pinus sylvestris L.)

Up-to-date field studies and monitoring document cement pollution impact on forests (Farmer, 2002). In Lithuania, since the 1990s, reduced level of emissions in a cement factory (CF) caused further adverse changes in the surrounding forests and some disturbances were registered in the ongoing decade. The present study was aimed to evaluate whether present level of pollution caused by the cement factory affects nutrition and general vitality of Scots pine (Pinus sylvestris L.) growing along 10 km transect. Sites near the CF differed in the amounts of aerial sulfur dioxide up to 9 times. The highest total deposition of calcium, potassium and sulphur reached 4.9 kg Ca ha-1 month-1 (creating 12-24 times differences between sites), 0.9 kg K ha-1 month-1 and 2.0 kg S ha–1 month–1 respectively and bark acidity (pH) of the transect pines ranged between 6.5 and 5.1. The concentration of 29 elements (N, P, Ca, Mg, Mn, Fe, Zn, B, Cu, Co, Mo, Al, Sr, Ba, Ti, Ni, Cr, Pb, V, Ag, Zr, La, Li, Nb, Y, Ga, Sc, Sn, Yb) were determined in the soil samples and 23 elements (C,N, K, P, Ca, S, Mg, Mn, Fe, Zn, B, Cu, Co, Mo, Al, Sr, Ba, Ti, Ni, Cr, Pb, V, Ag) in the needles of pine. In addition, on the surface of the needles Ca and some other elements were analysed. Significant differences between the stands were found according to the concentration of most elements. The highest concentrations of some nutritional elements – Fe, Mg, Mo, Cu and nonessential elements – Al, Ti, Sr, Ba, Cr, Pb, V, Ag were found in the needles of pines growing in the most polluted site. Relations between the cement dust, the needle, needle surface and soil elemental concentrations are discussed. Elevated concentrations of non-essential elements in the needles of pines growing in the most polluted area around the factory might be a reason of the worst condition of the treesChemijos institutasVytauto Didžiojo universitetasŽemės ūkio akademij