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Scots pine, as one of the dominant European tree species in the temperate zone, is experiencing intensified water deficits, especially in north-western and central Poland, where it suffers from frequent droughts and generally low precipitation. This work investigates drought impact on forest functioning, by analysing ecosystem transpiration under normal as well as dry conditions. Therefore, eddy covariance (EC) and sap flow measurements (using the thermal heat balance, THB, method) were combined to estimate transpiration (T) in two different-aged Scots pine (Pinus sylvestris) stands in north-western Poland: Mezyk (ME; 26 years old) and Tuczno (TU; 67 years old). Transpiration (T) estimates regarding EC measurements were derived from gross primary productivity (GPP) fluxes and vapour pressure deficit (VPD) dependence, considering their common relationship with stomatal activity. In 2019, the year following severe drought in Poland and Europe in general, total annual transpiration estimated based on sap flow measurements (TSF) was significantly lower than EC-derived transpiration (TEC) at both sites. The total ratio of TSF/TEC for the growing season (March–August) was 0.64 and 0.41 at ME and TU, respectively. We thus speculate that the understory, which was more abundant in TU than in ME, and which could only be observed by the EC system, may be responsible for the observed discrepancies. Bigger differences between TSF and TEC occurred under dry and wet conditions, while both were fairly similar under moderate conditions. The analysis of the relationships between TSF and soil water content (SWC) at depth of 10 cm revealed that there is a thresholds (SWC ~ 3.5%) at which TSF starts to decrease sharply, presumably due to stomatal closure. However, the decrease in GPP fluxes at the same time was less pronounced, indicating the impact of additional non-stomatal factor on water conductivity. We generally conclude that care should be taken if the conclusion of the occurrence of drought stress of some plants is derived from a bulk evapotranspiration flux, as it is commonly done with EC measurements averaging over the whole ecosystem. Our results also support the notion that non-stomatal water losses are an important element during extreme dry conditions, and that these may appear not only when stomata are already closed. [ABSTRACT FROM AUTHOR]

Digit ratio is a morphological feature regarded as a biomarker of the balance of sex hormones during early development. The exposure of embryos to a set of sex hormones and the mutual relations between those hormones cause the emergence of individual morphological and/or behavioural characteristics as well as differences between sexes. We have thus hypothesised that differences in one of these morphological traits—digit ratio—may be a proxy representing a tendency towards tail autotomy. The aim of this study is to investigate the digit ratio (2D:3D, 2D:4D, 3D:4D) of the sand lizard, Lacerta agilis, Lacertidae, a species characterised by well‐developed sexual dimorphism, whereby females are larger than males. We also tested associations between patterns in digit ratio and caudal autotomy, a common defensive mechanism among lizards. To our knowledge, the relationship between a tendency towards autotomy and digit ratio pattern has never been researched. To date, studies on autotomy have mainly focused on the consequences, costs or evolutionary background of tail loss. Hence, researchers examined mostly the frequency of autotomy in the context of predatory pressure or habitat conditions, omitting an individual's behavioural tendency to shed its tail. However, behavioural traits can affect an individual's exposure to predator attack and consequently the need to use an anti‐predator strategy. Thus, following this logic, dropping the tail may be the result of the lizard's intraspecific personality characteristics, resulting from the effect of hormones on behaviour or innate traits. Therefore, we suggest that the inclusion of autotomy as a factor explaining observed digit ratio patterns and their variability between taxa has great potential. We used computerised measurements of photographed limbs to determine the length of digits. We found that the digit ratios for all four limbs were significantly lower in females than in males, excluding the 3D:4D ratio for the right hindlimbs. Therefore, the results confirmed the pattern already observed for most lizards. The novel element in our study is the detection of the relationship between a tendency towards caudal autotomy and digit ratio. Individuals with a tendency towards autotomy have a higher 2D:4D ratio in the right forelimbs and a lower 2D:3D ratio in the right hindlimbs. Obtained results suggest that these morphological characteristics are most likely related to intraspecific differences (between bold and shy individuals) which consequently may determine an individual's reaction or susceptibility to be a prey and escape behaviour. Thus, our results are probably the first attempt to link digit ratio to the susceptibility of lizards to tail autotomy. [ABSTRACT FROM AUTHOR]

• Beech undergrowth increases the loads of alkaline cations in Scots pine stand. • Increased acidification of the 0–15 cm soil layer was observed in Scots pine with beech. • Lower ALK and ANCaq of soil water (15–60 cm) was found in solid Scots pine stand. The aim of the presented research was to assess the changes in selected ecochemical indices along the vertical precipitation profile - rainwater passing through the tree canopy and penetrating the topsoil. Two Scots pine stands were selected for this comparison (at one of them beech undergrowth was introduced), located at the Tuczno research site near the existed eddy covariance tower. The concentration of basic cations and anions in the collected water samples was measured and the following indices were calculated: Acid Neutralising Capacity (ANC aq), Alkalinity (ALK), Basic Cation Saturation (BS%) and Calcium to Aluminum ratio (Ca/Al). Additionally, Dry Deposition Factor (DDF) and Canopy Exchange for potassium, calcium, and magnesium cations were estimated (CE_K+, CE_Ca2+and CE_Mg2+, respectively). Observed changes in these variables values in throughfall (TF), as compared to bulk precipitation, at both pine stands during the investigated period 2013–2015 indicate that rainwater was enriched with almost all analyzed ions after passing through the canopy. Moreover, the mean annual deposition of all elements in throughfall was higher in the pine stand with beech undergrowth (SP + Bch) than at the plot with Scots pine only (SP). The average value of the DDF index was almost 3 times higher in the pine stand with beech undergrowth than at solely pine stand. Along with the depth in the soil profile, the ANC aq and ALK decreased. The main conclusion was that introduction of beech undergrowth in the pine stand most likely resulted in the accumulation of more organic matter and thus a slower decomposition rate, as suggested by an increase in acidification of the topsoil (0–15 cm). However, such an effect was not visible in the deeper layers. Higher values of ALK, ANC aq , and pH value under pine stand with beech undergrowth indicate positive effect of beech undergrowth in pine stands. [ABSTRACT FROM AUTHOR]

Carbon and water dynamics of disturbed forest sites differ significantly from the mature stand. Stand-replacing phenomena as windthrow do not only alter forests' ability to sequester carbon but also affects water vapor exchange with the atmosphere due to the great reduction of evapotranspiration. The choice of reforestation technique at these vulnerable post-windthrow sites turns out to be crucial regarding not only net CO2 emissions changes in time but also the young plantation resistance to the water stress conditions. In this study we have compared results of already 6 years of continuous, real-time measurements at two windthrow forest sites in Trzebciny Forest District in northwest Poland. The main objective of this study was to determine how two completely different reforestation techniques in windthrow areas impact net ecosystem production (NEP) of this Scots pine forest ecosystem under similar meteorological and soil conditions. These two techniques were: conventional (Tlen I site- uprooted stumps pulled out and removed from the site followed by ploughing), and non-conventional (Tlen II site- all stumps left on the site to decompose with no ploughing). At both sites we measured carbon dioxide (CO2) and water (H2O) fluxes using the eddy covariance (EC) technique. Our results indicate that both sites became significant carbon (C) sources after the windthrow (up to 575 56 g C m-2 y-1 in the first year, Tlen I). However, the Tlen I (conventional technique) lost over 30% less C than Tlen II during the 2015-2016 observation period. In the next two years (2017-2018) the decrease in net C emission was several times greater at Tlen I than at Tlen II. Moreover, the annual net ecosystem production (NEP) at conventionally reforested windthrow site reached C neutrality (NEP = 0) six years after windthrow, while the non-conventionally managed area was still a significant C source. So far then, the currently widely applied conventional reforestation technique in wind-disturbed Polish forest appeared to be more effective in decreasing C losses than a technique that leaves stumps to decompose and avoids ploughing. During the study period there were two relatively wet years (2016 and 2017) which allowed both Scots pine plantations to grow and develop very well. Although, the occurrence of summer drought in 2015 affected the non-conventionally reforested treatment, while at the site which had been ploughed, there was no sign of water stress. It comes from the fact that furrows, where organic matter lays upside-down on the previous soil cover, served well as a retention agent, supplying young trees with water at the times of its shortage. Similar effect was visible also in spring 2018. The results from both study areas were also compared with CO2 and H2O fluxes from the mature pine stand (Tuczno site) - the closest analogue to the pre-storm stands from the Tlen I and Tlen II sites. Presented studied gives an insight into the carbon and water dynamics at differently managed wind-disturbed forest sites, stressing out the differences in coping with water stress. [ABSTRACT FROM AUTHOR]

Huge amounts of carbon being sequestered in forest ecosystems make them an important land carbon sink at the global scale. Their ability to withdraw carbon dioxide (CO 2 ) from the atmosphere, whose concentration is gradually increasing due to anthropogenic emissions, renders them important natural climate-mitigation solutions. The urgent need for transition from high to zero net emission on country, continental, and global scales, to slow down the warming to an acceptable level, calls for the analysis of different economic sectors' roles in reaching that ambitious goal. Here, we examine changes in CO 2 emission and sequestration rates during recent decades focusing on the coal-dominated energy sector and Land Use, Land-Use Change, and Forestry (LULUCF) as well as wood production at the country level. The main purpose of the presented study is to examine the potential of storing carbon in standing forest biomass and wood products in Poland as well as the impact of disturbances. The ratio of LULUCF absorption of CO 2 to its emission in Poland has ranged from about 1% in 1992 to over 15% in 2005. From a climate-change mitigation point of view, the main challenge is how to maximize the rate and the duration of CO 2 withdrawal from the atmosphere by its storage in forest biomass and wood products. Enhancing carbon sequestration and storage in forest biomass, via sustainable and smart forestry, is considered to be a nature-based climate solution. However, not only forests but also wood-processing industries should be included as important contributors to climate-change mitigation, since harvested wood products substitute materials like concrete, metal, and plastic, which have a higher carbon footprint. The energy perspective of the paper embraces two aspects. First, CO 2 sequestration in forests and subsequently in harvested wood products, is an effective strategy to offset a part of national CO 2 emissions, resulting largely from fossil fuel burning for energy-production purposes. Second, wood as biomass is a renewable energy source itself, which played an important role in sustaining energy security for many individual citizens of Poland during the unusual conditions of winter 2022/2023, with a scarce coal supply. [ABSTRACT FROM AUTHOR]

[Display omitted] • New approach for LST-VI scatterplot usage in forest moisture condition monitoring. • Change spatial heterogeneity necessity for temporal variability in TVDI calculation. • Model produces moisture indices maps which are directly comparable with each other. • All calculations performed in Python 3 using open source libraries, • No auxiliary data are necessary. Land Surface Temperature (LST) against Vegetation Index (VI) scatterplot is a base concept of Temperature Vegetation Dryness Index (TVDI) which is a widely used drought index taking into account evaporation over heterogenic area. The main advantage of using TVDI is that it reflects rather a soil moisture conditions than volumetric soil moisture itself. This is particularly useful when the aim of conducting research is to assess water availability for plants rather than volumetric soil moisture at some depth. Results that have been obtained so far using indices based on LST-VI scatterplot proved their effectiveness in meadows, pastures or crops but were not satisfactory enough over forest areas. An important limitation of using TVDI is a need to collect LST and VI data from heterogenic areas, to provide different soil moisture conditions which is often difficult to ensure. In this paper, we proposed a new approach to the TVDI calculation method in which we use temporal variability of soil moisture conditions (shown in different satellite images of the same area) instead of their spatial heterogeneity. Calculations were conducted over the forest area in Tuczno Poland. To calculate the temporal TVDI model 4 Landsat 8 OLI/TIRS scenes were used, and calculation was performed in Python 3 using open-source packages. The average moisture conditions of each chosen scene were validated using field data, namely evapotranspiration determined from an eddy covariance. [ABSTRACT FROM AUTHOR]

Simple Summary: Alcohol consumption is quite common in the bird world. Using scientific literature and Internet resources (available because of the rising popularity of social media), we investigate which species and sources of ethanol are most frequently used by captive and wild birds. Moreover, it was possible with the internet videos to discriminate between intentional and unintentional ingestion. This information may be helpful in choosing appropriate species for future laboratory studies about ethanol metabolism in birds and their behaviour. Ethanol is a natural by-product of the fermentation process of fruit sugars and is occasionally consumed by fruit-eating and tree sap drinking birds. Information on this form of alcohol consumption features in the scientific literature. However, as pets or as wild animals living close to humans in urban habitats, birds have increasing possibilities to consume alcohol from beverages, such as beer, wine or spirits. Some observations have been discussed in a light-hearted manner in mass media and social media, but without any generalization of why some bird species drink the beverages intentionally or unintentionally provided by humans. To check which species and in what circumstances birds drink alcohol and how this is evaluated by humans, we reviewed the scientific literature and analysed videos from YouTube. In total we found and analysed 8 scientific papers and 179 YouTube videos, from which we identified at least 55 species (in some cases not all birds were identified to species level), 11 in the scientific literature and 47 in videos. The distribution of these species over the avian phylogenetic tree suggests that the origin of this convergent behaviour is mainly by human influence. The two data sources differed in the species covered. Videos typically presented interactions of birds with human-provided alcoholic beverages, and were dominated by two groups of intelligent birds: parrots and corvids. The popularity of YouTube videos for a particular species was positively correlated with the general popularity of the species as measured by the number of hits (results listed) on Google. Human responses to the videos were generally very positive and we analysed how the responses were influenced by factors derived from viewing the videos. Moreover, YouTube videos also provide information on at least 47 new bird species not previously mentioned as using alcohol, and our results suggest that parrots in particular can be potentially good candidates for future restricted laboratory studies on the effect of ethanol on birds and their relationship with humans. [ABSTRACT FROM AUTHOR]