Growth and Productivity of Non-Indigenous Woody Species in the Middle Urals

Climate warming has been recorded over the last decades. The air temperature in Yekaterinburg has been rising since the 1930s. Temperatures dropped sharply in 1940–1949, then rose sharply and fell again, especially in 1967–1968, when many large introduced species considered to be adapted died: Phellodendron amurense Rupr. and Pseudotsuga taxifolia (Lindl.) Britt. Due to the cyclical nature of weather conditions, it was necessary to assess the features of adaptation and state of the introduced plants in recent years. Snowless autumn and winter, temperatures above zero in early spring are unfavourable for many species, especially or conifers. Thus, in 2014 much snow fell on October 16 and melted in 2 weeks, temperatures below zero did not afford plants to prepare for the winter; in March 2015 the temperature rose up to +10 °C while the ground temperature was below zero for a long time. As a result of physiological dryness 100 % of specimens of variegated forms of northern white cedar Thuja occidentalis L. `Ellwangeriana Aurea`, `Ericoides` died. In other forms the leafage died to the snow cover level and recovered after abundant rains: `Aurea spicata`, `Gold Pearl`, `Golden Globe`, `Lutescens`, `Semperaurea` and `Wareana Lutescens`. Due to a steady increase in the sum of positive temperatures and reaching a certain age, many conifer species entered the fruiting stage and gave self-seeding: Pinus peuce Grieseb, Pinus strobus L., Picea canadensis (Mill.) Britt. et al., Picea pungens Engelm., Pseudotsuga taxifolia (Lindl.) Britt., and Abies sachalinensis (F. Schmidt) Mast. In the warmest year of 2016, the latter gave an abundant yield – red-brown cones with protruding seed scales; a strong wind dropped them all. They remained under the snow for the winter and did not crumble (probably, the fruits were unripe), so Abies sachalinensis was mistaken for Keteleeria fortunei (A. Murray bis) Carrière), which has cones that do not crumble. Unusual flowering was observed in Crataegus oxyacantha L. `Rosea Plena`, Mespilus germanica L., Syringa reflexa C.K.Schneid, Hamamelis virginiana L. With the rise in average annual temperatures, the number of years with abnormal weather conditions increased and the condition of some plants deteriorated. For citation: Semkina L.A., Tishkina E.A. Growth and Productivity of Non-Indigenous Woody Species in the Middle Urals. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 6, pp. 100–109. DOI: 10.37482/0536-1036-2021-6-100-109

Genetic Dissection of Growth and Eco-Physiological Traits Associated with Altitudinal Adaptation in Sakhalin Fir (Abies sachalinensis) Based on QTL Mapping

(1) Background: The genetic basis of local adaptation in conifers remains poorly understood because of limited research evidence and the lack of suitable genetic materials. Sakhalin fir (Abies sachalinensis) is an ideal organism for elucidating the genetic basis of local adaptation because its altitudinal adaptation has been demonstrated, and suitable materials for its linkage mapping are available. (2) Method: We constructed P336 and P236 linkage maps based on 486 and 516 single nucleotide polymorphisms, respectively, that were derived from double digest restriction site-associated DNA sequences. We measured the growth and eco-physiological traits associated with morphology, phenology, and photosynthesis, which are considered important drivers of altitudinal adaptation. (3) Results: The quantitative trait loci (QTLs) for growth traits, phenology, needle morphology, and photosynthetic traits were subsequently detected. Similar to previous studies on conifers, most traits were controlled by multiple QTLs with small or moderate effects. Notably, we detected that one QTL for the crown area might be a type-A response regulator, a nuclear protein responsible for the cytokinin-induced shoot elongation. (4) Conclusion: The QTLs detected in this study include potentially important genomic regions linked to altitudinal adaptation in Sakhalin fir.

Ten Years of Provenance Trials and Application of Multivariate Random Forests Predicted the Most Preferable Seed Source for Silviculture of Abies sachalinensis in Hokkaido, Japan

Research highlights: Using 10-year tree height data obtained after planting from the range-wide provenance trials of Abies sachalinensis, we constructed multivariate random forests (MRF), a machine learning algorithm, with climatic variables. The constructed MRF enabled prediction of the optimum seed source to achieve good performance in terms of height growth at every planting site on a fine scale. Background and objectives: Because forest tree species are adapted to the local environment, local seeds are empirically considered as the best sources for planting. However, in some cases, local seed sources show lower performance in height growth than that showed by non-local seed sources. Tree improvement programs aim to identify seed sources for obtaining high-quality timber products by performing provenance trials. Materials and methods: Range-wide provenance trials for one of the most important silvicultural species, Abies sachalinensis, were established in 1980 at nine transplanting experimental sites. We constructed an MRF to estimate the responses of tree height at 10 years after planting at eight climatic variables at 1 km × 1 km resolution. The model was applied for prediction of tree height throughout Hokkaido Island. Results: Our model showed that four environmental variables were major factors affecting height growth—winter solar radiation, warmth index, maximum snow depth, and spring solar radiation. A tree height prediction map revealed that local seeds showed the best performance except in the southernmost region and several parts of northern regions. Moreover, the map of optimum seed provenance suggested that deployment of distant seed sources can outperform local sources in the southernmost and northern regions. Conclusions: We predicted that local seeds showed optimum growth, whereas non-local seeds had the potential to outperform local seeds in some regions. Several deployment options were proposed to improve tree growth.

Geographical Gradients of Genetic Diversity and Differentiation among the Southernmost Marginal Populations of Abies sachalinensis Revealed by EST-SSR Polymorphism

Research Highlights: We detected the longitudinal gradients of genetic diversity parameters, such as the number of alleles, effective number of alleles, heterozygosity, and inbreeding coefficient, and found that these might be attributable to climatic conditions, such as temperature and snow depth. Background and Objectives: Genetic diversity among local populations of a plant species at its distributional margin has long been of interest in ecological genetics. Populations at the distribution center grow well in favorable conditions, but those at the range margins are exposed to unfavorable environments, and the environmental conditions at establishment sites might reflect the genetic diversity of local populations. This is known as the central-marginal hypothesis in which marginal populations show lower genetic variation and higher differentiation than in central populations. In addition, genetic variation in a local population is influenced by phylogenetic constraints and the population history of selection under environmental constraints. In this study, we investigated this hypothesis in relation to Abies sachalinensis, a major conifer species in Hokkaido. Materials and Methods: A total of 1189 trees from 25 natural populations were analyzed using 19 EST-SSR loci. Results: The eastern populations, namely, those in the species distribution center, showed greater genetic diversity than did the western peripheral populations. Another important finding is that the southwestern marginal populations were genetically differentiated from the other populations. Conclusions: These differences might be due to genetic drift in the small and isolated populations at the range margin. Therefore, our results indicated that the central-marginal hypothesis held true for the southernmost A. sachalinensis populations in Hokkaido.

Growth of Abies sachalinensis Along an Urban Gradient Affected by Environmental Pollution in Sapporo, Japan

Urban tree growth is often affected by reduced water availability, higher temperatures, small and compacted planting pits, as well as high nutrient and pollution inputs. Despite these hindering growth conditions, recent studies found a surprisingly better growth of urban trees compared to trees at rural sites, and an enhanced growth of trees in recent times. We compared urban versus rural growing Sakhalin fir (Abies sachalinensis (F. Schmidt) Mast.) trees in Sapporo, northern Japan and analyzed the growth differences between growing sites and the effects of environmental pollution (NO2, NOX, SO2 and OX) on tree growth. Tree growth was assessed by a dendrochronological study across a gradient from urban to rural sites and related to high detailed environmental pollution data with mixed model approaches and regression analyses. A higher growth of urban trees compared to rural trees was found, along with an overall accelerated growth rate of A. sachalinensis trees over time. Moreover, environmental pollution seems to positively affect tree growth, though with the exception of oxides OX which had strong negative correlations with growth. In conclusion, higher temperatures, changed soil nutrient status, higher risks of water-logging, increased oxide concentrations, as well as higher age negatively affected the growth of rural trees. The future growth of urban A. sachalinensis will provide more insights as to whether the results were induced by environmental pollution and climate or biased on a higher age of rural trees. Nevertheless, the results clearly indicate that environmental pollution, especially in terms of NO2 and NOX poses no threat to urban tree growth in Sapporo.