Baltic Forestry

The genetic and environmental variance of radial increment in Scots pine of south-eastern Baltic provenances in response to weather extremes

Roberts Matisons, Oskars Krišāns, Diāna Jansone, Āris Jansons, Pauls Zeltiņš — Fri, 02 Feb 2024 00:00:00 +0200

Intensification of weather anomalies, particularly those related to temperature in warming winters and moisture availability, have been identified as the major emerging climatic threats to forest ecosystems in the hemiboreal zone. Considering the large-scale nature of the threats, assisted migration and tree breeding appear as the most promising means for mitigating the climatic risks. However, for successful implementation of such means, information on the genetic control over the weather sensitivity of trees is needed. Local genetic adaptations of populations occur to maximize competitiveness and survival, while the differences in phenotypic plasticity, implying varying genotype by environmental interactions, can be utilized for the acquisition of locally targeted reproductive material. To gain initial (rough) estimates of genetic control and phenotypic plasticity of growth responses to weather anomalies, a set of seven native eastern Baltic provenances differing by productivity in five trials in Latvia and northern Germany were studied. Tree-ring widths were measured for 10–15 trees per provenance per trial. Relative growth changes and pointer year values were calculated to link changes in increment with weather anomalies and to estimate heritability on an annual basis by the methods of quantitative genetics. During the analysed period (1987–2017), four to seven trial- and provenance-specific pointer years (common relative growth changes) were estimated, which were mainly triggered by co-occurring anomalies in moisture availability and winter thermal regime. This implied resilience of the studied trees to singular weather anomalies, suggesting their adaptability. Furthermore, the heritability estimates peaked one to two years after the pointer years, implying that growth recovery and hence resilience rather than resistance was genetically controlled. Still, local variability of pointer years and heritability estimates portrayed explicit phenotypic plasticity of responses, implying the potential for breeding to locally improve weather tolerance of growth.

Keywords: Pinus sylvestris; local adaptation; phenotypic plasticity; growth recovery; tree-ring width; pointer years

Semi-mechanized planting of saplings: pivotal results on the efficiency of a new method

Wed, 10 Apr 2024 00:00:00 +0300

Large clear-cut areas as a consequence of drought and bark beetle infestations necessitate extensive replanting efforts in German forests, leading to an increased interest in efficient planting systems. In addition to manual planting, mechanized and semi-mechanized systems utilizing surplus forest machine capacities available after completion of salvage logging operations are likely required for timely reforestation of the clear-cut areas. A semi-mechanized system utilizing a standard forwarder with a grapple-actuated soil borer for both, the transport of planting material and the preparation of planting pits, combined with two workers carrying out manual planting, was investigated in a time-and-motion study. The frequency method was used after video recording of a planting operation that covered an area of approximately 1.2 hectares. A total of 815 alder saplings (Alnus glutinosa L.) with heights of 1.2–1.5 m were planted. Observed productivity was 93 saplings per system work hour (SWH). With additional placement of stakes for stabilizing the plants, the productivity decreased to 42 saplings per SWH. While directly comparable results were not found in the literature, available productivity figures of purely manual planting systems do not suggest an increased productivity of this semi-mechanized system. Considering ergonomics, however, forwarder utilization provides reduced workload not only in plant hole preparation but also with material transport and clearing of planting spots. Both the ergonomic aspects of the system and, in particular, the suitability of the soil borer for different soil textures should be further investigated.

Keywords: time studies; forwarder; stand regeneration; windthrow; forest operations

Effect of sowing density on performance and biometric features of pedunculate oak

Maria Hauke-Kowalska, Winicjusz Kasprzyk — Wed, 13 Mar 2024 00:00:00 +0200

Sowing density is one of the most important factors influencing seedling quality. In forest nurseries, to ensure full seeding, it is recommended to obtain approximately 200 seedlings from 1 m² (ZHL 2012). The aim of the study was to assess the effect of sowing density on sowing efficiency and the morphological features of pedunculate oak seedlings. Acorns were sown directly by broadcast seeding on 20 test plots, each 4 m in length, in four replications. The following variants were used:
- 250 acorns capable of germination totaling 341 acorns per 1 linear meter (0.9 m²);
- 300 acorns capable of germination totaling 410 acorns per 1 linear meter (0.9 m²);
- 350 acorns capable of germination totaling 478 acorns per 1 linear meter (0.9 m²);
- 400 acorns capable of germination totaling 546 acorns per 1 linear meter (0.9 m²);
- 450 acorns capable of germination totaling 614 acorns per 1 linear meter (0.9 m²).

At the end of the growing season, seedlings were counted per 1 m (0.9 m²) in the central part of each plot. Sowing efficiency was determined as a percentage of seedling yield from the sown seeds. For laboratory analysis, 30 seedlings from each plot (600 in total) were collected. Based on biometric features like shoot height, root collar diameter, and dry weights of shoots, roots, and leaves, quality indicators such as the sturdiness quotient (SQ) and the Dickson quality index (DQI) were calculated.

Sowing efficiency at the end of the vegetation season ranged between 39.68% and 50.12% and was not statistically significant. The research revealed that sowing density influenced seedling biometric characteristics. Pearson’s correlation coefficients showed significant negative correlations between the number of seedlings obtained in an experimental plot and the dry weight of the root, number and dry mass of leaves, as well as the DQI. The seedlings from all sowing variants complied with the binding Polish standard, outlined in the Regulation of the Minister for the Environment of 18 February 2004 (Ministerstwo Środowiska 2004) by over 96%.

Keywords: seeding density, sowing rate, seedling quality, sowing performance, sturdiness quotient (SQ), Dickson quality index (DQI), Quercus robur L.

Invertebrates occurring in fruiting bodies of the pathogenic tinder fungus, Fomes fomentarius (Polyporales), in the different types of Polish protected forests

Wed, 07 Feb 2024 00:00:00 +0200

Bracket fungi are usually considered as a cause of economic losses, while they also offer specific microhabitats and have an impact on biodiversity. However, to date this topic has not been sufficiently studied. The aim of this article is to show how the diversity of invertebrate communities, viz. spiders, harvestmen (Araneae, Opiliones), pseudoscorpions (Pseudoscorpionida), two groups of mites (Mesostigmata and Oribatida), springtails (Collembola), and insects (Insecta), inhabiting fruiting bodies of the tinder fungus, Fomes fomentarius, depend on specific characteristics of forests. Samples were collected in three locations: the Białowieża National Park (BNP) characterised by a high degree of forest naturalness, the Bieszczady National Park (BdNP), which was transformed by human, but has been undergoing naturalisation for several decades, and the Karkonosze National Park affected by a large-scale forest dieback in the 1980s and which for years has been under strong tourist pressure. A total of 20 fruiting bodies of F. fomentarius were collected at each location. In total, 9,821 individuals of invertebrates belonging to 204 species were extracted. The most numerous group was Oribatida (6,595 individuals classified to 106 species), while the most numerous species was Carabodes femoralis (5,216 individuals). The study sites differed in the number of species (the highest one was observed in the BdNP, 115, and the lowest one in the KNP, 88) and number of individuals (the highest one was observed in BdNP, 4,285, and the lowest one in BNP, 1,595), as well as the number of individuals per species (the highest one was observed in the BdNP, 37.26 individuals per 1 species, and the lowest in the BNP, 15.79 individuals per 1 species). A NMDS analysis revealed that the inner distribution of the samples in each of the locations was similar in the case of mountain national parks (BdNP and KNP), while the invertebrate groupings from the BNP and KNP differed the most between one another. The multilevel pattern analysis showed different, specific invertebrate species for each study sites, e.g. Carabodes subarcticus for the BNP, Friesea mirabilis for the BdNP, Oribatella calcarata for the KNP and Dendrolaelaps pini for both mountain national parks. This study shows the uniqueness of invertebrate communities inhabiting fruiting bodies of F. fomentarius and confirms the positive role of this pathogenic fungus in shaping biodiversity.

Keywords: arthropods; bracket fungi; polypores; anthropopressure; natural forest

A Methodology for verifying/determining the boundaries of Game Management Regions: a case study of the Regional Directorate of the State Forests in Lublin (Poland)

Maciej Wójcik, Katarzyna Tajchman, Malwina Michalik-Śnieżek, Vladimir Hanzal — Wed, 13 Mar 2024 00:00:00 +0200

Wildlife management is an integral part of forest management, and game animals should be considered an essential part of the forest ecosystem and agroecosystems in which the flow of energy changed fundamentally during the 20^th century due to the use of fertilisers, pesticides, and modern technologies. An approximately four-fold increase in the production of crops brought with it an increase in the number of ungulates in the world. The tasks of foresters and hunters in wildlife management include creating the best suitable living conditions for animals and mitigating conflicts between forest animals and human activities. This necessitates the creation and implementation of modern land units called Game Management Regions (GMRs) in Poland. This concept was defined in the Polish Hunting Law primarily for managing big game populations. The aim of the GMRs is to ensure year-long management of game populations within their respective ranges. Long-term Hunting Management Plans were developed for each GMR, serving as the basis for adopting management directions, and achieving the desired state of the game population as recorded in the multi-year plan (typically spanning ten years).
However, experiences and the current situation reveal several weaknesses in the functioning of these divisions, including rapid changes in the environment, particularly the emergence of barriers like highways and new buildings. This research aimed to develop a method for determining or verifying the boundaries of the GMRs based on objective criteria as a case study hosted by the Regional Directorate of State Forests in Lublin. During the conducted analysis we examined data provided by the Regional Directorate of State Forests (RDSF) in Lublin, including information on the current density of red deer (Cervus elaphus), forest cover, forest patch fragmentation, categories of hunting districts, ecological corridors, as well as existing, under-construction and planned highways and expressways.
The boundaries of the GMRs were determined by aggregating hunting districts with similar characteristics using GIS software while considering ecological barriers. The analysis results indicated the need to establish 12 divisions instead of 8, with significant deviations from the previous delimitation. The obtained results underscore the necessity of verifying the boundaries of the GMRs nationwide.

Keywords: large-scale game management; big game; Game Management Region; hunting plans