Paleoecological and historical data as an important tool in ecosystem management.

In recent decades, it has been observed that most forest fires in Europe were caused by people. Extreme droughts, which are more often prolonged, can increase the risk of forest fires, not only in southern Europe but also, in Central Europe. Nonetheless, catastrophic fire events are not well recognized in the Central European Lowlands (CEL), where large forest complexes are located. Knowledge of past fire activity in this part of Europe is scarce, although several fires have occurred in this area during the previous millennia. Large coniferous forest monocultures located in the CEL are highly susceptible to fires and other disturbances. Here, we present a case study from the Tuchola Pinewoods (TP; northern Poland), where large pine monocultures are present. The main aim of this study is to document the potential effects past land management has on modern day disturbance regimes using state-of-the-art paleoecological data, historical documents and cartographic materials. We then present a protocol that will help forest managers utilize long-term paleoecological records. Based on paleoecological investigations, historical documents, and cartographic materials, our results show that, in the past 300 years, the TP witnessed not only disastrous fires and but also windfalls by tornados and insect outbreaks. A change in management from Polish to Prussian/German in the 18th century led to the transformation of mixed forests into Scots pine monocultures with the purpose to allow better economic use of the forest. Those administrative decisions led to an ecosystem highly susceptible to disturbances. This article provides a critical review of past forest management as well as future research directions related to the impacts of fire risk on land management and ecosystem services: (a) habitat composition and structure (biodiversity); (b) natural water management; and (c) mitigation of climate changes. Designated forest conditions, management, and future fire risk are a controversial and highly debated topic of forest management by Forestry Units. More research will allow the gathering of reliable information pertinent to management practices with regard to the current fire risks. It is necessary to develop a dialog between scientists and managers to reduce the risk of fires in projected climate change.

Shore zone in protection of water quality in agricultural landscape-the Msciwojów Reservoir, southwestern Poland.

Shore zones are transition areas (ecotones) between aquatic and terrestrial ecosystems. Their function in the environment is crucial because they serve as buffer zones that capture pollutants and slow down erosion of reservoir and watercourse banks provided that they are managed properly. Research on a shore zone was conducted at the Msciwojów retention reservoir with an innovative water self-purification system. After several years of its operation, an increased phosphate concentration in the main part of the reservoir was reported. The mapping of the terrain's surface and modeling of hydrological processes in the direct catchment area of the said reservoir were done using the digital elevation model (DEM). The DEM was created from LiDAR data obtained in 2012 by airborne laser scanning. Analyses of the surface runoff led to identification of surface runoff transport pathways, along which the eroded material from cultivated fields is discharged directly to the reservoir. Surface runoff transport pathways gather the eroded material from a maximum area of 45,000 m(2) in the western part of the direct catchment and 40,000 m(2) in the eastern part of it. Due to the reservoir management negligence, the riparian zone designed for the Msciwojów Reservoir no longer exists. The percentage of the natural shore that undergoes erosion processes is over 54. The said processes and fluctuations of the water level in the reservoir, as well as degradation of the shore zone caused by human activity, bring about limited plant development in the littoral zone, which in turn lowers the reservoir's resistance to degradation.

Measured and predicted freeze-thaw days frequencies in climate change conditions in central Poland.

The rate of progression of geomorphological phenomena is greatly influenced by freeze-thaw processes. In the face of air temperature increasing over the past few decades, a question of the future impact of these processes arises, notably in the temperate and cold climate zones. Using the mean, maximum and minimum daily air temperature data in the period 1951-2018 obtained from three weather stations located in the vicinity of Jeziorsko reservoir (central Poland), we have determined the mathematical correlation, described with a polynomial function, between the mean monthly air temperature and the monthly number of freeze-thaw days (FTD). A freeze-thaw day is a day when the maximum air temperature is above 0 °C while the minimum air temperature equals or is below this threshold. The number of FTDs within the study area averaged 64-71 and demonstrated a downward trend of 2-4 FTDs/10 years. The study period (1951-2018), includes a clearly marked distinct sub-period (1991-2018), when the reservoir was in operation, which experienced 58-68 FTDs. Considering the assumed rise in temperature, one should expect a further, though slightly slower, decline in the future number of FTDs. Depending on the accepted model of the temperature increase, which for the area of Poland (Central Europe) in the perspective of 30 years oscillates between +1.1 to +1.3 °C, the number of FTDs within the study area is expected to decline by -4.5 to -5.3 FTD, i.e. 6-7% and 5.4-5.5 FTD i.e. 8-9% respectively.

The role of freeze-thaw action in dam reservoir cliff degradation assessed by terrestrial laser scanning: A case study of Jeziorsko Reservoir (central Poland).

Cliff recession is a combined result of wave action in the shore zone and geomorphological processes in the transformed cliff. As several processes usually take place simultaneously or consecutively, so distinguishing between the impact of each one of them individually on cliff erosion is impossible. Jeziorsko Reservoir is characterized by large fluctuations of water level in the annual cycle (several metres), hence in winter, when the water level in the reservoir is the lowest, the exposed cliff is not directly influenced by wave erosion. Sediments resulting from freeze-thaw action are accumulated at the bluff toe. However, in early spring, when freeze-thaw processes are continued, the water level in the reservoir is elevated, reaching the bluff toe. Wave erosion in that period causes removal of the material accumulated at the bluff toe and, consequently, cliff degradation. These processes interact. In 2015, the normal water level in the reservoir was lowered by 0.5 m leaving the bluff toe unaffected by wave erosion also in spring and summer months. These conditions enabled us to distinguish between the effects inflicted by freeze-thaw action and other sub-aerial geomorphological processes and wave erosion on cliff recession. This paper summarizes a series of detailed terrestrial laser scanning (TLS) measurements of morphological changes in an active cliff developing in coherent deposits in the temperate zone, resulting from freeze-thaw processes. Field research was conducted in 2014-2015 and 2018. The results of this study indicate that in coherent deposits in the temperate zone freeze-thaw action plays an important role among sub-aerial geomorphological processes such as wetting and drying of the surface sediments, linear erosion or mass movements causing cliff recession.