Global maps of soil temperature.

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km <sup>2</sup> resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km <sup>2</sup> pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

Global maps of soil temperature

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world\u27s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

Conductivity test for Scots pine (Pinus sylvestris L.) and Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) seeds vitality assessment

The level of damage to the cell membranes is a sign of aging of the seeds and a decrease in their viability. Conductometric seed testing method indirectly utilizes uncontrolled leakage of ions from seeds with damaged cell membranes to assess their viability. This involves the use of an electrical conductivity of the aqueous solution, in which seeds are soaked. The research was conducted in the years 2011−2014 and aimed at developing the methodology of evaluation of Scots pine and Douglas fir seeds by conductivity test. The aim of the study was to determine the relationship between electrolyte leakage and germination capacity of Scots pine and Douglas fir seeds. 402 samples of Scots pine seed and 90 specimens of Douglas fir seed from all over Poland were tested. The research material was both freshly harvested and stored. Scots pine seeds were obtained in the years 2008−2014, while Douglas fir – 2003−2013 as well as ones stored in the refrigerator for 15 years. Conductivity test and standard seed germination procedure of the analyzed species were used. For both Scots pine and Douglas fir, we noted that, as the electrolyte leakage rate increased, the germination capacity of the seed decreased. So we decided to test whether the vitality of the seeds was determined by means of a conductivity test. The best−fit regression model was determined and the mean expected germination capacity in the viability classes was calculated. 95% confidence intervals for the regression function were also determined. Evaluation of the viability of the seeds by means of the conductometric method is especially useful for seeds requiring a long stratification period (e.g. Douglas fir to determine the potential loss of their vitality. Although the ISTA seed evaluation rules do not require conductivity test for evaluating the seeds of Scots pine and Douglas fir, it may be applicable in situations where it is necessary to perform a rapid assessment of viability before spring sowing

Comparative analysis of database access technology

The paper’s subject is comparative analysis of database access technologies. It presents the evolution of the discussed technologies, which are divided into the following categories: single-platform and multi-platform technologies. Sample programs showing the use of programming interfaces, used for initiating and establishing connections with databases and performing simple operations on them. A database diagram, which was used for measuring efficiency of selected technologies as well as testing plan and concept, system and hardware parameters, tested queries and the program skeleton that was used for measuring the efficiency of selected technologies, were presented. The results were grouped according to 4 query types and 3 operating systems. A description was attached to each graph. Conclusions were provided for query tests for each of the operating systems. Finally, the most efficient technologies were discussed, potential causes of increase or decrease in efficiency were presented, and the results were summarized

Variability of the selected traits of Picea abies (L.) Karst. cones and seeds depending on their location in the crown

The objective of the study was to determine whether differences exist between the selected characteristics of Norway spruce cones and seeds depending on their location in the crown. The study was performed in two spruce tree stands growing under mountainous conditions (the Beskidy Mountains, southern Poland). In winter 2015, the cones were collected from 60 standing trees located in the two selected seed stands – Ujsoły and Rycerka. From each tree, the cones were collected from three crown zones: top, central and bottom differing in terms of light conditions. Two characteristics of the cones and six characteristics of the seeds were analysed. To determine quantitative and qualitative traits of seeds standard methods for seed testing were applied. Significant differences between the populations were determined for cone weight and fraction of full seeds, weight of 1000 seeds and germination capacity. The crown zones differed significantly in terms of fraction of cones in the parts of the crown and mass of one cone as well as weight of 1000 seeds, germination energy and germination capacity. Moreover, a significant intra−population variation was observed for a majority of the analysed characteristics (fraction of full seeds, weight of one cone, weight of 1000 seeds, germination energy, and germination capacity). However, no statistically significant interaction between population and crown zone was observed. A significantly lower contribution of cones in the bottom zone of the crown may affect the economic viability of the commercial harvest. On the other hand some of the important seeds traits (e.g. weight of 1000 seeds, germination energy and germination capacity) were significantly better in the bottom and central part of the crown than in the top zone. There are no justified circumstances (both qualitative and quantitative) to perform the cone harvest only from the top zone of the crown

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

UAV AND GIS BASED TOOL FOR COLLECTION AND PROPAGATION OF SEEDS MATERIAL – FIRST RESULTS

Seed management carried out by The State Forests National Forest Holding is an integral part of rational forest management. Seed collection takes place mainly from stands belonging to first category of forest reproductive material, which is the largest seed base in Poland. In smaller amount, seeds are collected in selective objects of highest forest reproductive material category (selected seed stands, seed orchards). The previous estimation methods of seed crop were based on visual assessment of cones in the stands for their harvest. Following the rules of FRM transfer is additional difficulty of rational seed management which limits the possibility of the use of planting material in Poland. Statements concerning forecast of seed crop and monitoring of seed quality is based on annual reports from the State Forest Service. Forest Research Institute is responsible for preparing and publishing above-mentioned statements. A small extent of its automatization and optimization is a large disadvantage of this procedure. In order to make this process more effective web-based GIS application was designed. Its main performance will give a possibility to upload present-day information on seed efficiency, their spatial pattern and availability. Currently this system is under preparation. As a result, the project team will get a possibility to increase participation of seed material collected from selected seed base and to share good practices on this issue in more efficient way. In the future this will make it possible to obtain greater genetic gain of selection strategy. Additionally, first results presented in literature showed possible use of unmanned aerial system/vehicle (UAS/V) for supporting of seed crop forecast procedure

Structure and dynamics of uneven−aged, Scots pine−dominated, old−growth stands in Kaliszki and Sieraków strict reserves in Kampinos National Park. Part 2. Tree mortality and recruitment processes and their effects on tree diameter distributions

Two fundamental demographic processes (tree recruitment and mortality) are analyzed for forest stands growing on permanent study plots located in strictly protected Scots pine−dominated, old−growth stands of Kampinos National Park (central Poland). The major implications of the observed demographic trends for the general shape of tree size distributions are determined, as well. During the past ca 30 years, in the stands sampled, there was a pronounced lack of balance between mortality and recruitment processes. Mortality rate was eight times higher than recruitment rate. Eventually, there was a net significant decline in population density, observed for all major tree species, including Scots pine, pedunculate oak, silver and downy birch, and black alder. As mortality processes affected mainly smaller trees, there was also a significant deterioration of the general demographic status of most important tree species. This effect was shown by the change of the overall shape of diameter distributions over the study period: from reverse J−shaped to flat curves running nearly parallel to X−axis. The values of recruitment rates were markedly lower, and the values of mortality rates – significantly higher, than analogous values characterizing comparable forests (e.g., those obtained for the natural stands of Białowieża National Park). Low recruitment rates, as obtained for Kampinos stands, suggest that presently, in the local, Scots pine−dominated, old−growth stands, the general conditions for forest regeneration and for maintaining a long−term demographic stability are unfavorable. Most probably, the regeneration of this type of forest has an episodic, ‘wave−like’ character and corresponds to the ‘catastrophic’ model, according to which the successful regeneration of current dominants (especially Scots pine, silver and downy birch, black alder) must be preceded by a stand−initiating (stand−replacing) disturbance, leading to total or partial, but heavy, destruction of the currently existing stand. At the moment, it would be difficult to predict, however, if and when such a disturbance will affect the stands under investigation. Thus, we predict that in the nearest future at least, the state of overall demographic unbalance will continue or even increase

Structure and dynamics of uneven−aged Scots pine−dominated old−growth stands in Kaliszki and Sieraków strict protection areas in the Kampinos National Park. Part 1. Species composition, tree density and basal area

The paper describes changes, which took place over the last 30 years in old−growth forest stands occupying two permanent research plots, established in the Kaliszki and Sieraków strict protection areas in the Kampinos National Park (central Poland). Both plots have a form of ecological transects. The Kaliszki plot is 20 m wide and 700 m long (1.40 ha), while the Sieraków plot (total area of 2.56 ha) consists of two parts: main (40×460 m) and side (40×180 m) transect. In the Kaliszki plot, the stand measurements were conducted in 1993, 2007, and 2017, while in the Sieraków plot – in 1989, 1994, 2006, and 2017. For every tree with breast height diameter (DBH) 5 cm, species identity, DBH and spatial coordinates were determined. Starting from the second census, all trees which had died (‘losses’), as well as trees which exceeded the DBH threshold (‘gains’) since the previous record were noted, as well. The major tree species occurring on sample plots are Scots pine (Pinus sylvestris), pedunculate oak (Quercus robur), silver and downy birch (Betula sp.), and black alder (Alnus glutinosa). During the study period, the overall tree density declined by ca. 50%. The diminishing trends occurred for all dominant tree species. In contrast to major, dominant tree species, the demographic status of a group of minor tree species (lime, hornbeam and maple) was much more stable. One may even speak about some expansion in this case. Particularly, hornbeam density increased rapidly in the period 2006−2017 in some areas of the main transect located in the Sieraków plot. The future studies will show if this tendency will be maintained and will include other regions of sample plots. Assuming a lack of significant disturbances, one may expect that the stands growing on research plots will rather slowly change in the nearest future. Most dynamics will have a quantitative and not qualitative character. One may anticipate, for example, a growing role of pedunculate oak at the expense of Scots pine, however, considering that the two species are rather long−living, they will probably for a long time keep their dominant roles in the stand canopies