Application of a Panel Data Quantile-Regression Model to the Dynamics of Carbon Sequestration in Pinus kesiya var. langbianensis Natural Forests

Even though studies on forest carbon storage are relatively mature, dynamic changes in carbon sequestration have been insufficiently researched. Therefore, we used panel data from 81 Pinus kesiya var. langbianensis forest sample plots measured on three occasions to build an ordinary regression model and a quantile-regression model to estimate carbon sequestration over time. In the models, the average carbon reserve of the natural forests was taken as the dependent variable and the average diameter at breast height (DBH), crown density, and altitude as independent variables. The effects of the DBH and crown density on the average carbon storage differed considerably among different age groups and with time, while the effect of altitude had a relatively insignificant influence. Compared with the ordinary model, the quantile-regression model was more accurate in residual and predictive analyses and removed large errors generated by the ordinary model in fitting for young-aged and over-mature forests. We are the first to introduce panel-data-based modeling to forestry research, and it appears to provide a new solution to better grasp change laws for forest carbon sequestration.

Analysis of the vitality of the Agathis dammara tree at Situ Gunung Resort, Gunung Gede Pangrango National Park

Vitality is the vigor value of the trees in responding to environmental conditions. Determined vitality value was by calculating tree damage and crown condition. The Agathis dammara tree is a native Indonesian plant in the Situ Gunung Resort, Gunung Gede Pangrango National Park (TNGGP). This study aims to determine the vitality and value of the health status of Agathis dammara trees at Situ Gunung Resort, TNGGP. The research location is in the utilization zone at the Situ Gunung Resort, TNGGP, covering an area of 700 haBuilt observation plots based on the Forest Health Monitoring (FHM) cluster plot design as many as nine cluster plots. They have calculated tree damage based on the location where found the damage was in the FHM method. Calculated condition canopy based on five parameters visual crown. Assessment of tree health status uses a forest health assessment information system. The results showed that the location where found the most damage was at the root and lower stem (code 2) as many as 67 trees, dominated by liana damage (code 20) as many as 43 trees, with an average damage level of 35%. The live crown ratio 20-35%, crown density 25-50%, foliage transparency 50-70%, crown diameter 2.5-10 m, and dieback 0-5%. The value of the health status of the Agathis dammara tree has a value of 1.69-2.44. Thus, these conditions illustrate that the vitality and value of the health status of Agathis dammara trees at Situ Gunung Resort, TNGGP are in the medium criteria and category.

Distribution and habitat use of the endangered Siberian flying squirrel Pteromys volans (Rodentia: Sciuridae)

Background Understanding the habitat characteristics of the endangered Siberian flying squirrel Pteromys volans is the first step in conserving and managing the forests it requires for nesting, gliding, and feeding. Therefore, in the present study, we characterized the habitats of P. volans using GIS analysis of 411 forest sites in South Korea where fecal droppings were found. Results Fecal signs of P. volans were found in various regions in South Korea, including the Baekdudaegan Mountains. GIS analysis with six environmental layers (vegetation type, wood-age class, diameter at breast height [DBH], crown density, elevation, and distance from stream) revealed that fecal signs of P. volans were more frequently found in broad-leaved deciduous forests (42%) located 200–399 m above sea level (43.1%) and 0–199 m from the nearest stream (53%), with 5th class wood-age (35.3%), middle size class DBH (51.1%), and high crown density (71%). Conclusions The present study provides information on the biotic and abiotic characteristics of P. volans habitats. In South Korea, the fecal droppings of P. volans were found predominantly old deciduous broadleaf forests. Further studies are needed to reveal whether the more frequent occurrence of P. volans dropping in broadleaf forests may be due to a particular preference of this species for the forests or to a simple reflection of the area of the broadleaf forests occupying a much larger area than other forest types in Korea.

Above-ground carbon storage in Pinus pumila along an alpine altitude in Khingan Mountains, Inner Mongolia of China

The carbon (C) cycle in alpine ecosystems is sensitive to climate change, but information about the C storage in its undergrowth is scarce. In October 2017, a total of 6231 Pinus pumila (Pall.) Regel trees were investigated for above-ground growth and density in 60 sub-plots (10×10 m) from 12 stands (50 × 50 m) along the altitudinal gradient (800-1500 m a.s.l.) in Great Khingan Mountains, Inner Mongolia, Northeast China. Sites were characterized by different crown densities (CDs) from 20% to 90%. Height and root-collar diameter (RCD) were higher in stands with CDs of 40-70% than CDs of 20-30%. Stem density (SD) and crown area (CA) had a positive correlation with altitude and CD. Equations from local shrub models were used to adapt the allometric growth models for estimation. There were variations in estimated above-ground C density depending on the model and the involvement of the canopy area. Above-ground C storage in P. pumila individuals ranged from 0.05-2.46 kg tree-1, which corresponds to C storage density ranged from 0.17-37-ton ha-1. The C density in P. pumila increased with crown density instead of stem density along increasing altitudinal gradients and increasing RCD. Hence, the crown density and diameter of a P. pumila plant can be used to predict the above-ground C density of its natural population.

Soil enzyme activity in the dry valley phytocenoses under the influence of Acer negundo L.

The activity of hydrolytic enzymes in the soil of dry valley phytocenoses under the influence of ash-leaved maple was investigated. The research objects were selected taking into account the ranking of plantations by crown density. Soil samples were collected depending on the horizontal differentiation of communities in the undercrown and outer zones of phytogenic fields. An increase in the enzyme activity during the period of active tree growth among experimental and control samples was established. Among the enzymes, invertase demonstrated the highest activity, while protease and phosphatase were characterised by medium activity. An increased invertase activity was found in the trees with a high crown density as compared to the trees of other groups. The obtained data can be used as diagnostic indicators of soil condition for monitoring natural ecosystems.

Fruiting of macromycetes in artificial plantations of Pinus sylvestris L. on the waste dump of the Kedrovsky open-cast coal mine

The quantitative registration of macromycete fruiting bodies was performed during two field seasons in the pine plantations of recultivated waste dump (experimental area) and in the pine forests on zonal soils (control area). The average quantity of carpophore macromycetes on the experimental area during two years of research exceeded ones on the control area by 41%. The field season of 2020 was characterized by significantly increased productivity of fungi in the studied areas; two peaks of mass fruiting of macromycetes were registrate. The maximum frequency of fruiting bodies of higher fungi was discovered in the autumn peak of mass fruiting mediated mainly by fair appearance of symbiotrophic fungi. Both studied areas in the different years of research were characterized by oppositely processes providing the distribution of carpophore macromycetes in pine plantations with different crown density (sparse, medium and dense). Taking into account the crown projection zones, the maximum frequency of macromycete fruiting bodies was located in the near-crown and outer zones of Pinus sylvestris L. trees.

The features of the biennial shoot systems of Ulmus glabra Huds. characteristic of the crown in the virginal age state

The morphological features of crowns were studied on the material of individuals of U. glabra of seed regeneration in the gaps of decaying three-hundred-year-old oak forests. We collected data on all crown shoots of five trees of young virginal age (from 10 to 18 years). The principal component method was used twice: first on the model tree to characterize features of the shoots biennial systems under the study, then to reveal ontogenetic and structural features of the crown organization of five virginal trees. Using the method of shoots biennial systems extraction allowed us to form a set of qualitative and quantitative characters reflecting crown structure properties of virginal trees of U. glabra, namely: properties of axes branching order, ontogenetic age of shoots in the crown, crown density, individual properties of tree crown structure.

Seed Regeneration of Buxus colchica Pojark. under the Conditions of Epiphytotics of Boxwood Forests

In response to expansion of Cydalima perspectalis Walker, 1859, mass scale drying of Buxus colchica Pojark. resulted in succession of forest communities of the Western Caucasus in 2014–2017. Changes in illumination of the forest low storeys were conducive to intensive growth of such herbaceous plants as Symphytum grandiflorum DC., Asarum intermedium (C. A. Mey. ex Ledeb.) Grossh., Festuca drymeja Mert. & W.D.J. Koch, Allium ursinum L., etc. and Ruscus colchicus Yeo, Geranium robertianum L., Rubus anatolicus Focke, Hedera colchica (K. Koch) K. Koch in the undergrowth. The ground vegetation with total projective cover up to 100 % was formed. Under current conditions the total number of B. colchica seedlings 2–15 cm high is only 10–320 pcs/ha on the southern macroslope and 5–87 pcs/ha on the northern macroslope. It is hundreds and thousands of times less as it was before boxwood forests extinction. The research purpose was to determine the factors effecting seed regeneration of B. colchica in the Western Caucasus under the conditions of succession caused by C. perspectalis expansion and further epiphytotics of boxwood forests. We carried out the studies on the southern and northern macroslopes of the Western Caucasus in the basins of the Khosta, Kurdzhips, and Tsitsa rivers in 2018–2019. The number of B. colchica seedlings was determined by their complete enumeration within 66 sampling plots; the area of each plot comprised 400 m2. When revealing the factors which effect seed regeneration of B. colchica, we analyzed 17 landscape and phytocenotic parameters: altitude above sea level; exposure and slope inclination; crown density of upper storey; parameters of undergrowth, main species stands, and dead boxwood; total projective cover of undergrowth and herbage. The principal factor preventing development of B. colchica seedlings is growthinhibition due to the herb-shrub storey. The total projective cover of undergrowth and herbage are the most important predictors for the number of B. colchica seedlings on the sampling plots. For the mentioned parameters we revealed the maximum regression coefficients b* at the significance level p < 0.05: –0.589 and –0.478 for the southern macroslope, and – 0.667 and –0.954 for the northern macroslope. The maximum projective cover of undergrowth in forest areas with boxwood regeneration is 50 % for both macroslopes. The maximum acceptable herbage cover is 15 % in the basin of the Khosta river, and 40 % in the basins of the Tsitsa and Kurdzhips rivers. Shading from the side of the forest upper storey suppresses growth of ground vegetation, and also prevents the development of B. colchica seedlings. Therefore the crown density, within the complex of factors, has no direct effect on the parameters of seed regeneration of B. colchica. In case of further intensive growth of the herb-shrub storey in forest phytocenoses, natural boxwood forests regeneration is highly improbable in the Western Caucasus. Artificial removal of undergrowth and herbage in forest areas will facilitate seed regeneration of the species. The research results are the basis for further monitoring of the regeneration processes of boxwood forests or their possible aboriginal change in the region.

Relationship between Species Richness, Biomass and Structure of Vegetation and Mycobiota along an Altitudinal Transect in the Polar Urals

Aboveground species richness patterns of vascular plants, aphyllophoroid macrofungi, bryophytes and lichens were compared along an altitudinal gradient (80–310 m a.s.l.) on the Slantsevaya mountain at the eastern macroslope of the Polar Urals (Russia). Five altitudinal levels were included in the study: (1) Northern boreal forest with larch-spruce in the Sob’ river valley habitats; (2–3) two levels of closed, northern boreal, larch-dominated forests on the slopes; (4) crook-stemmed forest; (5) tundra habitats above the timberline. Vascular plant or bryophyte species richness was not affected by altitudinal levels, but lichen species richness significantly increased from the river valley to the tundra. For aphyllophoroid macrofungi, species richness was highest at intermediate and low altitudes, and poorest in the tundra. These results indicate a positive ecotone effect on aphyllophoroid fungal species richness. The species richness of aphyllophoroid fungi as a whole was neither correlated to mortmass stocks, nor to species richness of vascular plants, but individual ecological or morphological groups depended on these parameters. Poroid fungal species richness was positively correlated to tree age, wood biomass and crown density, and therefore peaked in the middle of the slope and at the foot of the mountain. In contrast, clavarioid fungal species richness was negatively related to woody bio- and mortmass, and therefore peaked in the tundra. This altitudinal level was characterized by high biomass proportions of lichens and mosses, and by high litter mortmass. The proportion of corticoid fungi increased with altitude, reaching its maximum at the timberline. Results from the different methods used in this work were concordant, and showed significant patterns. Tundra communities differ significantly from the forest communities, as is also confirmed by nonmetric multidimensional scaling (NMDS) analyses based on the spectrum of morphological and ecological groups of aphyllophoroid fungi.

Designing Protective Ecotones to Reduce Acoustic Load on the Railway Lines

According to the results of the analysis of domestic and foreign literary sources, one of the most innovative ways of ensuring the stability of anthropogenically modified ecosystems is proposed, that is the creation of a system of protective type ecotones, which will allow providing ecological safety on the railways using exclusively natural environmental restoration mechanisms. On the experimental areas, we have described the taxonomic structure of forestry groups and phytocoenotic activity of species in forest grouping. We have also calculated the closeness, viability of the tree-stands, and also the projective shelter. To determine the noise effect, the noise-permeability of forest strips and the scattering of sound-currents from planting action have been analyzed. Based on research and calculations, a zone of sound shadow is determined depending on the size of the obstacle and the length of the sound wave. The acoustic effect of reducing the sound level is determined by such factors as bandwidth, dendrological composition, and design of plantations. The one-factor dispersion analysis allowed confirming that the investigated sections of the tracks of Lviv Railways differ significantly from each other according to these data. The results of the research were also subject to correlation analysis. The coefficients of pair correlation of structural indices of protective type ecotones were calculated with reduction of acoustic load on sections of the tracks of Lviv Railways. Therefore, the interrelation with the distance, the horizontal closure of the tree canopy, the distance between the trees, the height of the shaft and the crown density were reliably established. On this basis, the multiplicity regression equation for complex estimation of acoustic load reduction and prediction of noise reduction with specified parameters of protective type ecotones were calculated.