Genetic differentiation of Coregonus muksun in natural populations and broodstocks of fish rearing farms “Forvat” and “Sobsky” in relation to the problem of restoring the species population in Western Siberia

With regard to the problem of restoring the muksun (Coregonus muksun) population in Western Siberia by means of artificial regeneration, the genetic differentiation of natural populations and broodstocks of fish rearing farms “Forvat” and “Sobsky” was studied. Eighty-four sequences of mtDNA (3,006 bp) containing the highly polymorphic genes ND1 and ND2 were analysed. The differences between the populations of Western and Eastern Siberia were revealed. These findings must be taken into account when attempting to restore the species population in each particular region. The genetic closeness of the muksun from fish rearing farms “Forvat” and “Sobsky” with muksun from the Ob-Taz basin gives grounds for using these broodstocks for seeding the Ob and Taz rivers.

SEMEADURA DIRETA DE PATA-DE-VACA (Bauhinia ungulata L.) COM SEMENTES PRÉ-GERMINADAS PARA RESTAURAÇÃO FLORESTAL

Este estudo teve o objetivo de avaliar a estratégia de uso de sementes pré-germinadas de pata-de-vaca (Bauhinia ungulata L.) na semeadura direta para restauração florestal. Os tratamentos testados foram: T1= Plantio de mudas em tubetes (Testemunha); T2 = Semeadura direta sem pré-germinação; T3 = Semeadura direta com pré-germinação; T4 = Semeadura direta sem pré-germinação e hidrogel; e T5 = Semeadura direta com pré-germinação e hidrogel. O experimento foi instalado em blocos ao acaso com quatro repetições de 10 mudas ou pontos de sementes semeadas. Aos 100 e 210 dias de instalação do experimento foram feitas as seguintes avaliações: taxa de sobrevivência (Ts); altura total (Ht); diâmetro do colo (Dc); e número de folhas (Nf). A Ts e o crescimento morfológico de B. ungulata regeneradas pelo plantio de mudas não foram superadas pelas estratégias de semeaduras diretas utilizadas, mas a técnica demostrou ser promissora para futuros testes com outras espécies arbustivas e arbóreas de interesse à restauração florestal. Palavras-chave: área degradada; regeneração florestal; regeneração artificial. Direct seeding of pata-de-vaca (Bauhinia ungulata L.) with pre-germinated seeds for forest restoration ABSTRACT: This study aimed to evaluate the seed use strategy of using pre-germinated seeds of Bauhinia ungulata L. in direct sowing for forest restoration. The treatments tested were: T1 = Planting seedlings in tubes (Witness); T2 = Direct sowing without pre-germination; T3 = Direct sowing with pre-germination; T4 = Direct sowing without pre-germination and hydrogel; and T5 = Direct sowing with pre-germination and hydrogel. The experiment was installed in randomized blocks with four replications of 10 seedlings or points of seed sown. At 100 and 210 days after installation of the experiment, the following assessments were made: survival rate (Ts); total height (Ht); diameter (Dc); and number of leaves (Nf). The Ts and the morphological growth of B. ungulata regenerated by planting seedlings were not overcome by the direct seeding strategies used, but the technique proved to be promising for future tests with other shrub and tree species of interest to forest restoration. Keywords: degraded area; forest regeneration; artificial regeneration.

A short review on studies on work productivity of mechanical tree planting

Reforestation can be carried out using natural regeneration or artificial regeneration. There are vari-ous methods for the artificial regeneration, including manual planting, mechanical planting and aerial/or ground seeding. This article aimed to review the current reports on the productivity of mechanical planting to provide a summary of productivity rates for the planting machines. According to the review’s results, mechanical planting productivity may vary from 143 to 475 seedlings per productive machine hours depending on the machine type, environment (such as surfaces obstacles and stoniness) and the operator experience. Employing skilled operators and selecting suitable worksites can help increasing the work productivity. Integrating and optimising the whole planting chain, from the nursery to the plant-ing phase, can assist also with reducing the cost and improving the productivity. As mechanical planting machines get more widely adopted in different countries, their overall efficiency will improve over time.

Experimental Examination of Vegetative Propagation Methods of Nothofagus antarctica (G. Forst.) Oerst. for Restoration of Fire-Damaged Forest in Torres del Paine National Park, Chile

Nothofagus antarctica (Antarctic beech) is one of the main woody plants in the temperate deciduous forests and anti-boreal forests of the southern hemisphere. Since colonization of the Andean-Patagonian region by European settlers, however, stands of this species have been severely affected by fires caused by human activities, considerably reducing their area. To restore these forests to their area occupied before the fires, it is necessary to use artificial regeneration, relying on production of transplants in forest nurseries. Due to the low capacity for seed propagation, we focus on possibilities of producing seedlings by vegetative propagation. In a trial, we collected cuttings during three sets of dates, and attempted to root them using three combinations of substrate and ten combinations of stimulators. Using the most favorable combination of collection period, substrate and stimulator tested resulted in rooting of 23% of the cuttings, which exceeds the documented germination rates for this species.

The study of parent-regeneration relationships for wild cherry (Prunus avium L.) in Hyrcanian forests

The regeneration of forest trees is affected by the presence, dispersion pattern and specifications of parent trees. These effects were investigated and modelled in hardwood forests in the north of Iran. To do so, at first, fifty plots, each with a total area of 0.1 ha, were identified. Four subplots with a radius of two meters were then stabilized in each plot. The height and the root collar diameter of all the cherry seedlings were measured. Likewise, the diameter, basal area, and distance from the plot centre were appraised in the parent trees. The correlation and regression analyses were performed to evaluate the effects and to construct the models, respectively. The results showed that there was a positive and significant relationship between the presence, abundance, mean diameter, and total basal area of parent trees and the presence and abundance of seedlings. The logistic regression showed that the models based on the mean diameter of parent trees and abundance of parent trees could significantly predict the presence of regeneration. Only in 10% of the sample plots was the regeneration recorded without the presence of a parent tree. Due to the small number of established seedlings, while maintaining the existing parent trees, especially large trees, it is necessary to consider the proper management methods to promote and protect their regeneration. We recommend completing the natural regeneration of wild cherry by artificial regeneration and creating well-dimensioned canopy gaps.

Genetic comparison of planted and natural Quercus robur stands in Russia

Genetic diversity and the optimal genetic composition are essential for the adaptability and adaptation of tree populations. Artificial regeneration of stands might reduce the genetic diversity and increase family structures if the seeds were collected from a limited number of mother trees. We did a genetic inventory in 12 pedunculate oak stands in Russia using a set of 366 nuclear gene markers (361 SNPs, 5 Indels) in order to look for differences in the genetic composition among natural and artificial stands. Our results did not reveal any systematic differences among both types of stands. However, we found two extreme cases of limited genetic diversity and increased proportion of full-sibs and half-sibs in urban man-made stands. The implications for the forestry and gene conservation programs were discussed.

Germination of Dracaena cinnabari Balf.f. Seeds under Controlled Temperature Conditions

Research highlights: This study is focused on the germination of Dracaena cinnabari seeds in order to discover the possibility of natural and artificial regeneration of this species. Background and Objectives: This study aimed to determine the optimal temperature for D. cinnabari seed germination, e.g., the temperature at which the germination percentage and germination rate (vitality) are the highest. The objectives of this study are to: (1) determine the optimal temperature for the germination of D. cinnabari seeds, (2) compare the suitability of different seed collection methods, and (3) compare the germination parameters of seeds that were collected from different localities. The results of this study will contribute to obtaining the highest number of seedlings from limited seed material for reforestation of the most endangered localities of D. cinnabari species. Materials and methods: Four seed sections were employed. These sections were directly collected from either the fruits of a cut panicle or the ground and were obtained from different localities that differ in altitude. The seeds were tested in a greenhouse while using Petri dishes at three different temperatures—22, 26, and 30 °C—with four replicates of 25 seeds of each section. ANOVA and the t-test were employed for data analysis. Results: The highest germination percentages (GPs) were achieved at 26 °C and 30 °C, which were 84.6% and 82.5%, respectively. The ANOVA and t-test results showed that the germination index (GI) of the species was relatively higher at a temperature of 30 °C relative to that at other temperatures in the study. Although seeds that were collected from the tree achieved a higher GP, the t-test result showed no significant differences in the GI of D. cinnabari seeds that were collected from the ground and from the tree (p > 0.05). Overall, the findings of this study show that temperature has substantial influence on the germination of seeds of D. cinnabari. Therefore, we recommend a temperature of 30 °C to facilitate the germination of D. cinnabari, as it achieved the highest GI at this temperature relative to that at the other temperatures (22 °C, 26 °C) applied in this study.

Development of the Norway spruce (Picea abies /L./ Karst.) stand established by various spacings and affected by abiotic harmful factors and ungulate game

The paper presents the results of 30-year research on silviculture-production relationships in a 50-years-old Norway spruce stand (a small-pole stage) originated from artificial regeneration in a mountain forest. The stand was established in four different spacing variants: (i) 1.5 × 1.0 m, (ii) 2.5 × 1.0 m, (iii) 2.5 × 1.5 m, and (iv) 2.5 × 2.5 m. At each spacing, three management methods were investigated: geometric (schematic) intervention, mixed selective intervention, and control (no intervention). The development of the stand was disturbed by repeated snow breaks, rime and ungulate game damage. As a result of these harmful factors, the number of trees has declined markedly, especially in the last decade. This was also confirmed by an insufficient number of target trees in all trial variants. The analysis of quantitative production showed different results in some parameters. We found the most favourable results for the mixed selective method of tending. The 2.5 × 1.5 m spacing with an initial number of 2 667 trees per hectare or the spacing with an even lower number of plants was found to be appropriate under the given conditions.

Assessment of Tree Species for Fuelwood Consumption in Northern Guinea Savannah Eco-region: A Case Study of Selected Local Government Areas of Katsina State, Nigeria

Evaluation of preferred tree species for fuelwood consumption in selected local overnment area of Katsina State was studied. Random sampling techniques was used to administer thirty (30) questionnaire in each of the four (4) selected local government areas to make a total of one hundred and twenty (120) questionnaires. One hundred (100) were retrieved. The result revealed that Isoberlinia doka was the most preferred (24%) tree species for fuel consumption because of its high fire retaining capacity, low smoke and low moisture holding capacity while Cassia species and Odina barteri were the least (3% each). The major (70%) source of fuel wood supply to the market was from the forest. Funtua local government consumed more Fuelwood/head/year (64.06t/person/year) than all the other selected local government areas, while Sabuwa had the least (38.64 t/person/year). Fuelwood was the major (33%) energy source while gas (2%) was the least. Socio economic characteristics of the respondents were also examined. The percentage of male was 68%, while that of their female counterpart was 32%. Majority (50%) are married with many (35%) having 7-8 house hold size. 37% of the respondents had primary education while 26% had no formal education and majority (42%) were farmers. However, it is recommended that there is need for artificial regeneration of tree species exploited in form of woodlots, community forest plantation for continuous supply of wood on a sustainable bases and also other alternative sources of energy such as kerosene stove, gas cooker, solar etc should be encouraged and subsidized to the general populace to reduce the pressure on forest reserve.

Effect of climatic factors on forest succession in the forest-steppe zone of the Republic of Tatarstan

The paper analyzes the effect of climatic factors on forest succession in the forest-steppe zone of the Republic of Tatarstan. A reliable relationship was revealed between a decrease of the oak forested area and extremely low frosts in 1939–1940, 1941–1942 and 1978–1979, and a decrease in the area of birch after the 2010 drought. Birch and oak are replaced by maple, linden and aspen. Insignificant amount of young trees and the predominance of ripe and overripe plantations of oak and birch will lead to the continuation of forest succession in the forest-steppe zone. Impossibility of reverse succession at this stage by natural rehabilitation is associated with the biological characteristics of these species. Oak and birch forest rehabilitation is only possible with measures to promote natural or artificial regeneration with due regard to the biological characteristics of tree species.