Evaluation of Siberian Stone Pine Plantations at the End of the First Age Class

The 40-year-old plantations of Siberian stone pine laid out as a permanent seed plot have been studied. The research purpose is to study the integrity, state and main forest inventory parameters of the Siberian stone pine plantations on the southern line of the species range at the end of first age class; to determine the role of natural renewal of trees and shrubs on the development of the Siberian stone pine plantations; to improve process solutions for efficient renewal of high-value biological resources. The research uses the methods generally accepted in forestry, forest science and forest inventory. It is found that the integrity of Siberian stone pine on the site is about 31 % (678 pcs/ha), wherein 406 pcs/ha are without damage to the trunk. Only about 25 % of Siberian stone pine trees grow under low shade, the rest of them are constantly shaded by natural renewal and have varying degrees of suppression. No generative organs were found in 44-year-old Siberian stone pine trees. At the initial stage of plantations growth, the main factor negatively affecting the integrity and state of trees is the damaging of Siberian stone pine by moose. Traditional improvement thinning with leaving stumps that produce many shoots of deciduous species attracts moose to the site in winter, where they use young growth of deciduous species and the covered with needles part of Siberian stone pine as forage. Subsequently, in the absence of tending, natural renewal negatively affects the Siberian stone pine trees, inhibiting growth and formation. It is necessary to remove the negative influence in the mixed biocenosis in order to prevent further deterioration of the Siberian stone pine state. This requires completely different technological solutions for forestry activities such as ringing or injection of trees of natural renewal, causing drying at the root, which significantly reduces or eliminates the emergence of deciduous young growth. This will decrease the attractiveness of the site for moose and minimize their impact on Siberian stone pine. The clear drying of surrounding trees will enhance the illumination of Siberian stone pine crowns and improve their soil nutrition, ensuring good root, trunk, and crown growth and accelerating the beginning of the formation of generative organs. These technical solutions can be used throughout the forest zone for the artificial cultivation of the high-value species – Siberian stone pine. For citation: Terekhov G.G., Andreeva E.M., Stetsenko S.K. Evaluation of Siberian Stone Pine Plantations at the End of the First Age Class. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 6, pp. 56–68. DOI: 10.37482/0536-1036-2021-6-56-68

Nutrient Deficiency Affects the Growth and Nitrate Concentration of Hydroponic Radish

In hydroponics, a continuous supply of mineral nutrients is essential for plant growth. However, constitutive nutrient-rich conditions also increase the nitrate content in the plants, which can be harmful to human health. Here, we investigated the effect of nutrient deficiency on the growth and component composition of hydroponic radish by changing the timing of nutrient removal from the hydroponic solution. Radish plants that were 14 days old were transferred to four different nutrient conditions for 14 days: nutrient deficiency for 14 days (WW), full nutrient for 14 days (NN), nutrient deficiency for the last 7 days (NW), and nutrient deficiency for the first 7 days (WN). After the treatments, the NW plants had similar taproot growth to NN plants. In contrast, the WN plants significantly reduced taproot growth. The WW plants reduced the shoot and taproot weight and their water contents. The nitrate content in the taproots was reduced in the NW and WW plants. The WW plants contained lower total phenol and higher ascorbic acid and sugar contents. These results suggest that the uptake of nutrient minerals at the young growth stage is important for the growth of radish taproot. Nutrient deficiency management can be one of the most effective tools for regulating radish growth and composition.

Natural regeneration features of broad-leaved species under the canopy of coniferous stands in forest-steppe conditions

The age structure of the undergrowth was studied using the technique of constructing the age spectra of the adoles-cent population, which revealed the regularities of the natural pine recovery process. The aim of the study was to conduct a comparative analysis of the broad-leaved species renewal under the coniferous (pine) plantations canopy in forest-steppe conditions using the example of the Belgorod region. The research was carried out on 21 test areas using standard silvicultural techniques to assess natural regeneration effectiveness. Quercus robur L. and Ulmus laevis Pall. prevail among deciduous species in the second layer. Tilia cordata Miill, Fraxinus excelsior L., Acer platanoides L., Acer compestre L. reach less than 12%. (Betula pendula Ehrh., Populus tremula L.). The average number of young growth does not exceed 2000-2500 trees per hectare where the ones of medium height prevail (50%) and small height trees reach 22%. In the considered pine stands, Quercus robur L. young growth occurs more often. There is a growth that appeared from dormant buds at the root neck after the death of the seed unit. Units of normal vitality are found only among young growth younger than 5 years old or in communities with a disturbed stand structure.

ВІКОВА СТРУКТУРА ПІДРОСТУ CARPINUS BETULUS L. У КУЛЬТУРФІТОЦЕНОЗАХ НАЦІОНАЛЬНОГО ДЕНДРОЛОГІЧНОГО ПАРКУ «СОФІЇВКА» НАН УКРАЇНИ

The issue of preserving the dendrological structure in historical parks requires the implementation of a number of agronomic measures aimed at ensuring the decorative and durability of plant communities. The plants of Carpinus betulus L. are included in the vast majority of deciduous plantations of the National Dendrological Park «Sofiyivka» of NASU, form the stands with the participation of Quercus robur L., Acer platanoides L., Acer campestre L. and Fraxinus excelsior L. The question of self-recovery of C. betulus plants in the park is relevant in connection with natural waste and active reduction of its viability identified over the past 10 years. The analysis of the success of natural regeneration of aboriginal plants in the cultural phytocenoses of the National Dendrological Park «Sofiyivka» of NASU has been conducted. As a result of the survey of the dendrological structure, viability of the young growth of the main structure-forming species under the stand was revealed. The prospects of replacing senile plants of C. betulus with the younger generation have been outlined. The young growth of C. betulus is 4.5% of the total number of viable undergrowth in the test plots, which is significantly less compared to A. platanoides – 64.5 % and A. campestre – 20. 7%. There is a sufficient number of viable virginile and young generative plants of C. betulus, which in future is able to form a stand. Prospects for natural regeneration of plants of the C. betulus species are average, similar in quantitative and age characteristics to plants of the Fraxinus excelsior L. The number of virginile plants is 0.5 %, and young generative – 0.1 %, compared with A. platanoides and A. campestre, the results are more than 10 times lower for virginile and 2 times – for young generative plants, which indicates a weak competitiveness of the young growth of C. betulus. Artificial phytocenoses with the participation of C. betulus are one of a few self-regenerating species in the park, as aboriginal species have a higher adaptive potential and are capable of successful renewal. Control over the ratio of species and quantitative composition of undergrowth, timely rational sanitary and landscape felling will create optimal conditions for growth and development of the young growth of C. betulus. Regular removal of aggressive plants of A. platanoides, A. campestre and F. excelsior will help preserve the existing structure of the stand in the historic part of the NDP «Sofiyivka».

The Aging, Transformative Self

The transformative self is not just for the young. This chapter focuses on the aging self and how the person who has a transformative self interprets growth throughout the adult years. The chapter starts by debunking the popular belief—in both popular culture and academic psychology, despite the research evidence—that growth is just for the young. Research shows that older adults hold at least as many growth-oriented concerns as decline-oriented concerns, both in their memories and in their goals. However, growth is not a Pollyanna concept; eudaimonic growth is not easy. The chapter shows what young growth versus mature growth sounds like in personal narratives. Young and mature growth are examined in terms of concerns for self-identity, relational intimacy, and generative concern for future generations—and then in relation to well-being and wisdom.

Modeling specific gravity and diameter inside bark of western hemlock and Sitka spruce growing in southeast Alaska

Western hemlock and Sitka spruce are two commercially important species in Alaska with harvests beginning to focus on naturally regenerated young-growth. We developed within-tree models of ring specific gravity (SG) and diameter inside bark (DIB) for young-growth western hemlock and Sitka spruce. Eight even-aged stands (age < 75 years) in southeast Alaska were felled and disks collected from multiple height levels; 128 trees and 451 disks were collected for western hemlock, and 217 trees and 952 disks were collected for Sitka spruce. Radial strips were prepared and scanned using X-ray densitometry. We fitted non-linear mixed-effects models to the data, with cambial age, height within tree, and dominance class used as explanatory variables. The R2 values (fixed effects only) for the SG models were 0.48 and 0.42 for western hemlock and Sitka spruce, respectively. The corresponding fit indices for the DIB models were 0.86 and 0.85 percent for western hemlock and Sitka spruce, respectively. Tree maps depicting the within tree variation in SG showed more variability in Sitka spruce than in western hemlock. The wood and growth properties of young-growth trees in Alaska will continue to become more important as the U.S. Forest Service transitions away from harvesting old-growth trees.

Typological structure and age composition of beach stands in the mountainous Crimea

The features of the typological structure, age composition and territorial distribution of beech stands in the Mountainous Crimea were studied. It is shown that nowadays beech forests grow in the range of altitudes from 400-500 to 1300-1400 m above sea level on an area of 34.9 thousand hectares, which is 13.4% of the forested territory of the peninsula. The age structure of beech stands is characterized by the cyclical process of renewal of indigenous stands, which is determined by the implementation of favorable natural factors - the level of seed yield and weather conditions during the formation of seed renewal generation, the frequency of which is 40-50 years. Based on the analysis of the ecological spectrum of the species composition of the grass layer, it is established that the forest growing conditions in the beech stands in the central part of the Main Ridge of the Crimean Mountains should be characterized as fresh sudubravas and beech forests. The density of beech young growth in ecotopes in this area varies from 0.5 to 4 thousand pieces per 1 ha. In areas where the light regime improves, the young trees grow in the form of small bunches, often forming groups of young plants around the trunks of adult trees. Using satellite images of the Landsat 8 space sensing system, it was revealed that at present, in the central part of the beech forests of the Mountainous Crimea, significant areas are completely devoid of forest vegetation, or are covered with sparse woodlands, in the phytocenotic structure of which herbaceous plants predominate.

Structure of young growth of pine in various ecotopes of the Trans-Urals region

Рассмотрены результаты исследования пространственной и возрастной структуры подроста сосны на гарях-вырубках и вырубках сосняка брусничникового Среднего Урала. Показано, что подрост сосны на гарях-вырубках, по сравнению с вырубками, отличается значительно меньшей величиной диаметра на середине высоты ствола, но отличается существенно более высокими темпами роста в высоту. Относительная высота у подроста на гарях-вырубках на 31,5–37,3% выше, чем у подроста на вырубках. Связано это со значительно более высокой густотой подроста на гарях-вырубках, по сравнению с вырубками. Установлено, что большая часть возобновления сосны как на гарях-вырубках, так и на вырубках, была сосредоточена в районах примыкания трех сторон леса. С уменьшением источников обсеменения (примыкание двух сторон леса) густота подроста заметно снижалась. В свою очередь, на открытых участках на гарях-вырубках и вырубках численность подроста была наименьшей. Подрост сосны отличается регулярным (случайным) с переходом к рассеянному (равномерному) типом размещения на гарях-вырубках. На вырубках основной тип размещения – групповой. На гарях-вырубках основная часть деревьев относилась к возобновлению, появившемуся на 2–3-й год после пожаров и последующей вырубки. Возобновление, появившееся как на следующий год, так и на 4–5-й год после удаления древостоя, было незначительным. На 6-й год после пожара и вырубки возобновление полностью прекратилось. На вырубках основная часть деревьев относилась к возобновлению, появившемуся на 4–5-й год после вырубки. Однако, хотя и в значительно меньшей степени, возобновление сосны на вырубках имело место и в последующие годы. Закономерность изменения возрастной структуры подроста для гарей-вырубок хорошо аппроксимируется полиномиальным уравнением 4-го порядка, а на вырубках – 5-го порядка. The results of study of spatial and age structure of pine on slash-cutover and cutover of young growth of pine of cowberry-shrub pine forest of the Trans-Urals region are considered. It has been shown that the undergrowth of pine on slash-cutover in comparison with cutting differs by a significantly smaller diameter at the middle of the trunk height, but differs by a significantly higher growth rate in height. The relative height of the undergrowth on the slash-cutover was 31.5–37.3% higher than that of the undergrowth on the cutover. This is due to the significantly higher density of undergrowth on slash-cutover compared to cutover. It has been established that most of the resumption as pine on both slash-cutover and cutover was concentrated in the areas adjacent to three sides of the forest. With a decrease in sources of insemination (adjoining two sides of the forest), the density of undergrowth decreased markedly. In turn, in open areas on slash-cutover and cutover, the number of undergrowth was the smallest. The young growth of pine is characterized by a regular (random) with a transition to a scattered (uniform) type of placement on the slash-cutovers. In cutovers, the main placement type is group. On slash-cutovers, the main part of the trees belonged to the resumption, which appeared for 2–3 years after fires and subsequent felling. The resumption, which appeared both for the next year and for 4–5 years after the removal of the woodland, was insignificant. For 6-year after the fire and felling, the resumption completely ceased. On cutovers, the main part of the trees belonged to the resumption, which appeared for 4–5 years after felling. However, although to a much lesser extent, the resumption of pine on the cutovers, took place in subsequent years. The pattern of change in the age structure of undergrowth for cut-offs is well approximated by the polynomial equation of the 4th order, and on the cut-offs of the 5th order.

A JUVENILE METATARSAL OF CF. DASPLETOSAURUS TOROSUS: IMPLICATIONS FOR ONTOGENY IN TYRANNOSAURID THEROPODS

A well preserved, but isolated metatarsal III of a tyrannosaurid dinosaur, originating probably from the Dinosaur Park Formation of Alberta, Canada, is tentatively referred to Daspletosaurus torosus. The size of the specimen suggests that it likely comes from a large juvenile, since the width of the distal end is about 63 % of that of a much larger individual. The morphology of the specimen supports the recently suggested hypotheses that apomorphies of tyrannosaurid taxa may have developed at young growth stages, and that juveniles of albertosaurines and tyrannosaurines may be easier to distinguish from one another than previously thought. Additionally, the specimen reported here is important in that it provides an addition to the very poor juvenile fossil record of Daspletosaurus.