The Impact of Air Pollution on the Growth of Scots Pine Stands in Poland on the Basis of Dendrochronological Analyses

The aim of this study was to evaluate Scots pine stand degradation caused by the pollutants emitted from Zakłądy Azotowe Puławy, one of the biggest polluters of the environment in Poland for over 25 years (1966–1990). To assess the pollution stress in trees, we chose the dendrochronological analysis We outlined three directions for our research: (i) the spatio-temporal distribution of the growth response of trees to the stress associated with air pollution; (ii) the direct and indirect effects of air pollution which may have influenced the growth response of trees; and (iii) the role of local factors, both environmental and technological, in shaping the growth response of trees. Eight Scots pine stands were selected for study, seven plots located in different damage zones and a reference plot in an undamaged stand. We found that pollutant emission caused disturbances of incremental dynamics and long-term strong reduction of growth. A significant decrease in growth was observed for the majority of investigated trees (75%) from 1966 (start of factory) to the end of the 1990s. The zone of destruction extended primarily in easterly and southern directions, from the pollution source, associated with the prevailing winds of the region. At the end of the 1990s, the decreasing trend stopped and the wider tree-rings could be observed. This situation was related to a radical reduction in ammonia emissions and an improvement in environmental conditions. However, the growth of damaged trees due to the weakened health condition is lower than the growth of Scots pine on the reference plot and trees are more sensitive to stressful climatic conditions, especially to drought

Meteorological conditions of the occurrence of wind damage on August 11-12, 2017 in the forests of central-western Poland

Climate change, which was particularly marked at the turn of the 20th and 21st centuries, was accompanied by unfavourable weather phenomena. One of whose effects cannot be prevented is hurricane. Much of the most devastating storms (e.g. Kyrill in January 2007, Carmen in November 2010), which crossed over Poland, was associated with low pressure systems. The occurrence of high wind speeds in the cold season is a natural feature of Polish climate. Hurricanes in the summer are generally characterized by more complicated origin. The cause of the damage at this time of year may be squall fronts and tornados (e.g. July 4th, 2002 – Puszcza Piska; July 20th, 2007 – Częstochowa region). An important issue is to develop a category of winds for the forest district, which can have destructive effect on the stands. Current research shows that gusty winds exceeding 11 m/s may cause first damage to the trees, while blows with velocity exceeding 30 m/s result in severe damage. Knowing and monitoring the mechanisms that leads to strong winds, assessing their impact, and managing risk in the context of their effects is one of the important elements of a forest management strategy. On August 11th, 2017, after the influx of hot tropic air, much cooler polar air began to flow from the west. In the afternoon and evening storm cell and supercell began to form in the south−west of the country. Later on, they moved in the north direction forming a squall line. With a Mesoscale Convective System (MCS) moving to the north, there was a gusty wind exceeding 40 m/s in some places. A gust of wind occurred around 18.30 (EET) in Dolny Śląsk (SW Poland) and after about 2 hours in Pomerania (N Poland). The pressure tendency during the transition reached 4−5 hPa. In the northern part of the country, gusts of wind were the largest and occurred several times in 2−3 hours. The system was accompanied by heavy precipitations, which in north Poland determine more than 60% of the average monthly rainfall. The effect of moving MCS was the damage of almost 80 thousand hectares of forests in Poland, which of more than 39 thousand hectares were classified to complete restoration

Trends in the length of the thermal growing season in the north-eastern Poland

In the context of climate change and global warming, a growing number of studies reported lengthening of the growing season for most of the Northern Hemisphere, which is associated with increase of air temperature. Evidences of the increase of the growing season length were noted through satellite data and phonological and meteorological observations. This article presents the studies on the temporal and spatial tendencies in the thermal growing season (TGS) length in north−eastern Poland in 1951−2015. The analyses were conducted using long−term and homogeneity daily data sets from 13 meteorological stations (fig. 1). The dates of beginning and end of the TGS were determined by Huculak−Makowiec method. Trends in the TGS length as well as start and end dates were analysed for the whole study period as well as for successive 30−years periods: 1951−1980, 1961−1990, 1971−2000 and 1981−2010. The results show a general increase of the length of the TGS in the north−eastern Poland in 1951−2015 period, however, there are spatial and temporal differences in TGS evolution. In the western and central part of the region, the growing season in the past 65 years became ca. 20 days longer, while in the eastern part the lengthening of TGS was weaker and amounted to 7−10 days. Most of this change is due to earlier onset of the TGS in spring (average for the western part =2.1 days/10 years, while for the eastern one – 1.2 days/10 years). The observed trends and tendencies show spatial and temporal variability in TGS evolution. Trends in parameters of TGS, calculated for 30−years period, varied directionally and spatially with no significant trends before 1980. In the period 1981−2010 the growing season was longer than in the previous years, the largest increases were found in the central part of the region (1.2 days/year), while the smallest in the south−eastern part (0.5 day/year). Since the 1980s the frequency of long growing seasons increased. A particularly large and steady increase of TGS occurred over the first 15 years of the 21st century. Length as well as start and end dates of the TGS displayed large inter−annual and decadal variability with tendencies for increased range of variability

Air humidity on the clear-cut and the gap

The aim of the study was to determine the spatial variation of vapour pressure (e), relative humidity (f) and vapour pressure deficit (Δ) on the clear−cut and gap as well as to compare the spatial distribution of air humidity conditions on both areas. The research was carried out in Rogów Forest Experimental Station (51.827023°N, 19.922315°E) on a clear−cut with a width of 60 m and on a gap of an ellipsoid shape (40×70 m). The measurements were carried out in two series: spring−summer, i.e. in the period when the height of the sun during the day conditioned inflow of direct solar radiation to any surface (May−August 2006), and autumn, i.e. when direct radiation was limited by neighbouring stands (October−November 2006). We found the modest spatial diversification of vapour pressure that, on average, amounted to 0.4 and 0.2 hPa in the clear−cut and gap, respectively, in spring−summer period as well as 0.3 and 0.7 hPa, respectively, in the autumn. The major impact of the clear−cut and gap location was marked in relative humidity and humidity deficit. Differences in relative humidity on the clear−cut amounted averagely to 3.7 and on the gap 12.7%, whereas the humidity deficit equalled 0.3 and 5.4 hPa, respectively. Particularly large diversification of relativity humidity and vapour pressure deficit was in spring−summer period in the situation of heat waves. In that weather conditions in sun−filled clear−cut and gap parts, the relativity humidity fall to about 17%, whereas vapour pressure deficit increased to about 60 hPa. In the same clear−cut and gap parts the occurrence of dry days was more frequent that in other places. It was noticed that in the positions located in sun−filled clear−cut and gap parts (z4, g3), the diurnal vapour pressure course was very similar to the one observed in the forest, whereas the course of the relativity humidity and vapour pressure deficit was significantly different. That is mainly involved with the extreme thermal conditions in this parts of the studied areas. The least beneficial humidity conditions for plants growth occurred in the north−east parts of clear−cut and gap, that’s why it necessary to take particular note of these locations when undertaking the silvicultural treatments

Air temperature anomalies in experimental forests in Rogów in 1924–2015

Meteorological measurements, that aim to monitor weather and climate conditions to aid research in changing forest ecosystems, have been conducted in the Warsaw University of Life Sciences’ experimental forests in Rogów since 1924. Based on the long-term air temperature measurements, it can be demonstrated that in the years 1924–2015, anomalously cold months have occurred less often (ca. 3.2%) than anomalously warm months (ca. 4.5%). During the last 20 years, only two anomalously cold months were recorded (November 1998, December 2010), whereas anomalously warm months occurred frequently (May 2002, July 1999, 2002, 2006, 2010, 2012, 2014, August 2002, 2015, September 1999, 2006, October 2000, 2001). We hypothesised that the more frequent anomalously warm months would constitute a trend in increasing the air temperature for particular months between 1924–2015, but surprisingly, a statistically significant trend was observed for all winter (XII–II) and spring months (III–IV) as well as the end of summer (VIII)

The Impact of Long-Term Fertilisation of Potato Starch Wastewater on the Growth of Scots Pines: A Retrospective Analysis

The article discusses the impact of the application of potato starch wastewater as a fertiliser on the growth responses of Scots pines at the Forest Wastewater Treatment Plant (FWTP) in Iława. More specifically, our study sought to determine the direction, extent, and duration of changes in the trees’ growth responses caused by the application of fertiliser and the influence of climatic conditions on secondary growth in the trees to which the fertiliser had been applied. As part of the study, the extent of and changes in the growth responses were determined with reference to annual ring widths and earlywood and latewood widths using dendrochronological methods. The research was carried out in four pine stands: two stands of different ages (80 and 110 years) located within the FWTP site and two control stands of corresponding ages located outside that area. Core samples were collected from 12 trees in each stand. We found a two-way impact of potato starch wastewater on secondary growth in the trees under study, with a stimulatory effect (27%–30%) in the first decade of fertiliser application followed in the subsequent years by a strong reduction in growth (30%–45%, depending on the age of the trees). The trends of these changes could be seen in both the overall annual ring widths and the widths of earlywood and latewood. The direction of the changes was the same for trees of different ages, although age was found to have affected the extent and duration of the stimulatory or inhibitory effect. Over the entire period during which the fertiliser was applied, changes occurred in the structure of the wood as manifested in the increased share of earlywood. The sprinkler application of potato starch wastewater and the accompanying irrigation caused a shift in dendroclimatic relationships in comparison to the control plots. Surface irrigation and the resulting changes in water balance reduced the drought susceptibility of the pines under study. At the same time, however, trees weakened by the excessive concentration of toxic nitrates became more sensitive to temperature conditions in winter. The results confirm that the implementation of substances containing significant amounts of organic nitrogen and potassium into forest ecosystems may impair the vigour of trees, reduce stand productivity, cause an imbalance in the ecosystem and may consequently lead to forest degradation

The Impact of Long-Term Fertilisation of Potato Starch Wastewater on the Growth of Scots Pines: A Retrospective Analysis

The article discusses the impact of the application of potato starch wastewater as a fertiliser on the growth responses of Scots pines at the Forest Wastewater Treatment Plant (FWTP) in Iława. More specifically, our study sought to determine the direction, extent, and duration of changes in the trees’ growth responses caused by the application of fertiliser and the influence of climatic conditions on secondary growth in the trees to which the fertiliser had been applied. As part of the study, the extent of and changes in the growth responses were determined with reference to annual ring widths and earlywood and latewood widths using dendrochronological methods. The research was carried out in four pine stands: two stands of different ages (80 and 110 years) located within the FWTP site and two control stands of corresponding ages located outside that area. Core samples were collected from 12 trees in each stand. We found a two-way impact of potato starch wastewater on secondary growth in the trees under study, with a stimulatory effect (27%–30%) in the first decade of fertiliser application followed in the subsequent years by a strong reduction in growth (30%–45%, depending on the age of the trees). The trends of these changes could be seen in both the overall annual ring widths and the widths of earlywood and latewood. The direction of the changes was the same for trees of different ages, although age was found to have affected the extent and duration of the stimulatory or inhibitory effect. Over the entire period during which the fertiliser was applied, changes occurred in the structure of the wood as manifested in the increased share of earlywood. The sprinkler application of potato starch wastewater and the accompanying irrigation caused a shift in dendroclimatic relationships in comparison to the control plots. Surface irrigation and the resulting changes in water balance reduced the drought susceptibility of the pines under study. At the same time, however, trees weakened by the excessive concentration of toxic nitrates became more sensitive to temperature conditions in winter. The results confirm that the implementation of substances containing significant amounts of organic nitrogen and potassium into forest ecosystems may impair the vigour of trees, reduce stand productivity, cause an imbalance in the ecosystem and may consequently lead to forest degradation

Variation of radial growth of four Norway spruce provenances in central Poland

The purpose of this study was to determine the growth variability of four provenances of Picea abies on experimental plots in the Wyszków Forest District, central Poland. The experiment was established as a system of random blocks with four repetitions per block. We selected 48 trees from each provenance and the increment cores were colected from sample trees. Standard measurements of the width of annual increments were performed using the WinDendro software. Raw data was then indexed and subject to dendroclimatic analyses based on the average monthly temperatures and precipitation of the period from 1969 to 2012. Furthermore, the COFECHA software was used to check the consistency of the data and to determine the pointer years. High data consistency as well as growth variability of particular provenances in response to climatic conditions were observed. The results obtained here will allow for an improved selection of populations best suited for growing in the climate of central Poland