scholarly journals Diversity of lichens, mosses and vascular plants in the paludified herb-rich spruce forests of the Pinego-Mezen watershed (Arkhangelsk Region)

Author(s):  
S. A. Kutenkov ◽  
V. N. Tarasova

The paludified herb-rich spruce forests of the Pinego-Mezen watershed are characterized by a high speciesand coenotical diversity. The habitat type (floodplain, stream valley, mire margin) is the main compositional gradientfor vascular plant and moss diversity. The density, basal area and proportion of spruce and deciduous species in thetree stand are less significant. The main compositional gradient of the lichen diversity is the tree stand structure, whichprovides the availability and quality of the substrate for the epiphytic and epixilic lichens that prevail in such communities.The gradient of paludified herb-rich spruce forests from floodplain habitat to mire margins is less significant for thecomposition of lichen flora.

2021 ◽  
Author(s):  
Leszek Bartkowicz ◽  

The aim of the study was to compare a patch-mosaic pattern in the old-growth forest stands developed in various climate and soil conditions occurring in different regions of Poland. Based on the assumption, that the patch-mosaic pattern in the forest reflect the dynamic processes taking place in it, and that each type of forest ecosystem is characterized by a specific regime of natural disturbances, the following hypotheses were formulated: (i) the patches with a complex structure in stands composed of latesuccessional, shade-tolerant tree species are more common than those composed of early-successional, light-demanding ones, (ii) the patch-mosaic pattern is more heterogeneous in optimal forest site conditions than in extreme ones, (iii) in similar site conditions differentiation of the stand structure in distinguished patches is determined by the successional status of the tree species forming a given patch, (iv) the successional trends leading to changes of species composition foster diversification of the patch structure, (v) differentiation of the stand structure is negatively related to their local basal area, especially in patches with a high level of its accumulation. Among the best-preserved old-growth forest remaining under strict protection in the Polish national parks, nineteen research plots of around 10 ha each were selected. In each plot, a grid (50 × 50 m) of circular sample subplots (with radius 12,62 m) was established. In the sample subplots, species and diameter at breast height of living trees (dbh ≥ 7 cm) were determined. Subsequently, for each sample subplot, several numerical indices were calculated: local basal area (G), dbh structure differentiation index (STR), climax index (CL) and successional index (MS). Statistical tests of Kruskal- Wallis, Levene and Generalized Additive Models (GAM) were used to verify the hypotheses. All examined forests were characterized by a large diversity of stand structure. A particularly high frequency of highly differentiated patches (STR > 0,6) was recorded in the alder swamp forest. The patch mosaic in the examined plots was different – apart from the stands with a strongly pronounced mosaic character (especially subalpine spruce forests), there were also stands with high spatial homogeneity (mainly fir forests). The stand structure in the distinguished patches was generally poorly related to the other studied features. Consequently, all hypotheses were rejected. These results indicate a very complex, mixed pattern of forest natural dynamics regardless of site conditions. In beech forests and lowland multi-species deciduous forests, small-scale disturbances of the gap dynamics type dominate, which are overlapped with less frequent medium-scale disturbances. In more difficult site conditions, large-scale catastrophic disturbances, which occasionally appear in communities formed under the influence of gap dynamics (mainly spruce forests) or cohort dynamics (mainly pine forests), gain importance.


2020 ◽  
Vol 66 (No. 9) ◽  
pp. 349-360
Author(s):  
Stanislav Vacek ◽  
Rostislav Linda ◽  
Ivo Králíček ◽  
Karel Vančura ◽  
Anna Prokůpková ◽  
...  

The paper presents the results of a study on the impact of forest stand structure and development in 1998 to 2018 on the occurrence of dog’s tooth violets (Erythronium dens-canis L.) in the Medník National Nature Monument, Czech Republic. The research was carried out in mixed European hornbeam and sessile oak stands, herb-rich European beech stands and the Sázava-river Norway spruce ecotype stands. The site and stand characteristics of the following three forest stand types were compared: 1) oak-hornbeam forests, 2) herb-rich beech forests and 3) secondary spruce forests. The results showed that the ratio of sterile and fertile plants was 2.9 to 1. The occurrence of E. dens-canis was higher in older stands with differentiated structure. On the contrary, stands characterized by a higher number of trees and basal area negatively affected the population size of E. dens‑canis. Significantly, the density of E. dens-canis decreased with increasing stand density index (SDI) and increased with increasing diameter differentiation index in relation to tree neighbours (TM<sub>d</sub>). During the period of 20 years, the E. dens-canis population increased by 40.4% on permanent research plots, while the highest changes were observed on spruce plots (+92.1%) and the lowest increase was in oak-hornbeam forests (+18.0%). The highest numbers of E. dens-canis plants were found in herb-rich beech forests (1 774 plants·ha<sup>–1</sup>), lower numbers occurred in oak-hornbeam forests (784 plants·ha<sup>–1</sup>) and minimal in secondary spruce forests (51 plants·ha<sup>–1</sup>). <br /><br />


2019 ◽  
Vol 53 (1) ◽  
pp. 107-142 ◽  
Author(s):  
D. E. Himelbrant ◽  
I. S. Stepanchikova ◽  
T. Ahti ◽  
V. Yu. Neshataeva

The first lichenological inventory in Koryakia has resulted in the list of 315 species reported from Parapolsky Dale, within and in vicinities of the Koryak State Reserve. Altogether 46 species are published from the Kamchatka Territory for the first time, including Lecanographa grumulosa new to Russia, East Asia and Beringia; Cercidospora trypetheliza, Lecania dubitans, Pertusaria borealis, Piccolia ochrophora, Protoparmelia cupreobadia, Rimularia badioatra and Strangospora moriformis new to Russian Far East; Abrothallus bertianus, Cladonia strepsilis, Physciella melanchra, Rimularia badioatra, Sclerococcum parasiticum, Sphinctrina leucopoda and Strangospora moriformis new to Beringia. The lichen diversity of the study area is relatively poor due to natural reasons. Comparison with neighboring regions (Kamchatka Peninsula, Chukotka, Magadan Region, Yakutia and Alaska) shows that the lichen flora of Parapolsky Dale contains almost no specific species. The majority of the species recorded here are also known from neighboring regions, especially Alaska and Kamchatka Peninsula.


Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 843
Author(s):  
Ella R. Gray ◽  
Matthew B. Russell ◽  
Marcella A. Windmuller-Campione

Insects, fungi, and diseases play an important role in forest stand development and subsequently, forest management decisions and treatments. As these disturbance agents commonly occur within and across landscapes, modeling has often been used to inform forest planning and management decisions. However, models are rarely benchmarked, leaving questions about their utility. Here, we assessed the predictive performance of a Bayesian hierarchical model through on–the-ground sampling to explore what features of stand structure or composition may be important factors related to eastern spruce dwarf mistletoe (Arceuthobium pusillum Peck) presence in lowland black spruce (Picea mariana (Mill.) B. S. P.). Twenty-five state-owned stands included in the predictive model were sampled during the 2019 and 2020 growing seasons. Within each stand, data related to the presence of eastern spruce dwarf mistletoe, stand structure, and species composition were collected. The model accurately predicted eastern spruce dwarf mistletoe occurrence for 13 of the 25 stands. The amount of living and dead black spruce basal area differed significantly based on model prediction and observed infestation, but trees per hectare, total living basal area, diameter at breast height, stand age, and species richness were not significantly different. Our results highlight the benefits of model benchmarking to improve model interpretation as well as to inform our understanding of forest health problems across diverse stand conditions.


2016 ◽  
Vol 11 (2) ◽  
pp. 466-476
Author(s):  
Bijendra Lal ◽  
L.S. Lodhiyal

Present study deals with stand structure, biomass, productivity and carbon sequestration in oak dominated forests mixed with other broad leaved tree species. The sites of studied forests were located in Nainital region between 29058’ N lat. and 79028’ E long at 1500-2150 m elevation. Tree density of forests ranged from 980-1100 ind.ha-1. Of this, oak trees shared 69-97%. The basal area of trees was 31.81 to 63.93 m2 ha-1. R. arboreum and Q. floribunda shared maximum basal area 16.45 and 16.32 m2 ha-1, respectively in forest site-1 and 2 while Quercus leucotrichophora shared maximum (35.69 m2 ha-1) in site-3. The biomass and primary productivity of tree species ranged from 481-569 t ha-1 and 16.9-20.9 t ha-1yr-1, respectively. Of this, biomass and primary productivity of oak tree species accounted for 81 to 95 and 78 to 98%, respectively. Carbon stock and carbon sequestration ranged from 228 to 270 t ha-1 and 8.0 to 9.9 t ha-1yr-1, respectively. The share of oak tree species ranged from 81 to 94.7 and 79 to 97%, respectively. The diversity of tree species ranged from 0.03 to 0.16 in forest sites-1, 2 and 3. The diversity of oak species was 0.08-0.16 in all the forest sites. Thus it is concluded that among the oak tree species, Quercus floribunda and Quercus leucotrichophora were highly dominated in the studied forests. The climax form of oak dominated trees in the studied forest sites depicted slightly lower richness and diversity of tree species compared to the forests in the region and elsewhere. As far as dry matter and carbon of forests is concerned, these estimates are close to the earlier reports of forests in the region. Therefore, studied forests have the potential to increase the diversity, productivity and carbon sequestration of forest tree species by providing the adequate scientific conservation and management inputs.


2021 ◽  
Author(s):  
Mathias Neumann ◽  
Hubert Hasenauer

Abstract Competition for resources (light, water, nutrients, etc.) limits the size and abundance of alive trees a site can support. This carrying capacity determines the potential carbon sequestration in alive trees as well as the maximum growing stock. Lower stocking through thinning can change growth and mortality. We were interested in the relations between stand structure, increment and mortality using a long-unmanaged oak-hornbeam forest near Vienna, Austria, as case study. We expected lower increment for heavy thinned compared to unmanaged stands. We tested the thinning response using three permanent growth plots, whereas two were thinned (50% and 70% basal area removed) and one remained unmanaged. We calculated stand structure (basal area, stem density, diameter distribution) and increment and mortality of single trees. The heavy thinned stand had over ten years similar increment as the moderate thinned and unthinned stands. Basal area of the unthinned stand remained constant and stem density decreased due to competition-related mortality. The studied oak-hornbeam stands responded well even to late and heavy thinning suggesting a broad “plateau” of stocking and increment for these forest types. Lower stem density for thinned stands lead to much larger tree increment of single trees, compared to the unthinned reference. The findings of this study need verification for other soil and climatic conditions.


2021 ◽  
Vol 55 (1) ◽  
pp. 121-162
Author(s):  
D. E. Himelbrant ◽  
I. S. Stepanchikova ◽  
T. Ahti ◽  
V. Yu. Neshataeva

The lichen diversity of the Cape Goven within the Koryak State Reserve counts 394 species: 373 lichens, 18 lichenicolous fungi and 3 non-lichenized saprobic fungi related to lichens. Altogether 4 species are new to Russia (Miriquidica pulvinatula, Myriolecis andrewii, Ochrolechia alaskana, Rhizocarpon sublavatum), 1 – to Asiatic Russia (Collemopsidium foveolatum), 29 other species are new to the Russian Far East, 4 – to the northern part of the Far East. Additionally, 51 other species are new to Kamchatka Territory, and 92 more are new to Koryakia. Among the new species to Russia or Russian Far East, 11 are also reported for the first time for Beringia. A total of 500 species of lichens and allied fungi are known from Koryakia now. The richest habitats in Cape Goven are rocky outcrops and tundras; unlike in the earlier explored Parapolsky Dale, shrublands, floodplain stands and bogs play relatively insignificant role in the lichen diversity. The lichens of seashore communities enrich the lichen flora of Cape Goven compared to inland areas. The lichen diversity of Cape Goven is significantly higher than in Parapolsky Dale due to its mountainous landscape and coastal position.


2020 ◽  
Vol 139 (6) ◽  
pp. 989-998
Author(s):  
Sauli Valkonen ◽  
Lucie Aulus Giacosa ◽  
Juha Heikkinen

Abstract This study focused on tree mortality in spruce-dominated stands managed using the single-tree selection method in southern Finland. Together with regeneration and tree growth, mortality is one of the basic elements of the stand structure and dynamics in selection stands. The study was based on data acquired from a set of 20 permanent experimental plots monitored with repeated measurements for 20 years. The average mortality in the number of stems (N) was 4.45 trees ha−1a−1, in basal area (G) 0.07 m2 ha−1a−1, and in stemwood volume (V) 0.56 m3 ha−1a−1. In relative terms it was 0.50% of N, 0.30% of G and 0.27% of V, respectively. Wind and snow were the most common causes of mortality, while deaths by biotic causes (mammals, insects, pathogens) were extremely rare. Some 6–10% of the total loss in the number of stems and volume was attributable to the loss or removal of trees that sustained serious damage in harvesting. Most of the mortality occurred in the smallest diameter classes of up to 20 cm. Such a high mortality among small trees can have an adverse influence on the sustainability of selection structures if not successfully checked in harvesting and management.


2011 ◽  
Vol 28 (2) ◽  
pp. 92-96 ◽  
Author(s):  
Aaron R. Weiskittel ◽  
Laura S. Kenefic ◽  
Rongxia Li ◽  
John Brissette

Abstract The effects of four precommercial thinning (PCT) treatments on an even-aged northern conifer stand in Maine were investigated by examining stand structure and composition 32 years after treatment. Replicated treatments applied in 1976 included: (1) control (no PCT), (2) row thinning (rowthin; 5-ft-wide row removal with 3-ft-wide residual strips), (3) row thinning with crop tree release (rowthin+CTR; 5-ft-wide row removal with crop tree release at 8-ft intervals in 3-ft-wide residual strips), and (4) crop tree release (CTR; release of selected crop trees at 8×8-ft intervals). PCT plots had more large trees and fewer small trees than the control in 2008. There were no other significant differences between the rowthin and control. The rowthin+CTR and CTR treatments had lower total and hardwood basal area (BA) and higher merchantable conifer BA than the control. CTR also resulted in more red spruce (Picea rubens [Sarg.]) and less balsam fir (Abies balsamea [L.]) than the other treatments. Although stand structures for rowthin+CTR and CTR were similar, the percentage of spruce in CTR was greater. Although the less-intensive rowthin+CTR treatment may provide many of the same benefits as CTR, the latter would be the preferred treatment if increasing the spruce component of a stand is an objective. Overall, early thinning treatments were found to have long-term effects on key stand attributes, even more than 30 years after treatment in areas with mixed species composition and moderate site potential.


1989 ◽  
Vol 13 (2) ◽  
pp. 76-80 ◽  
Author(s):  
Robert L. Bailey ◽  
Thomas M. Burgan ◽  
Eric J. Jokela

Abstract Data from 263 plots in a regional fertilization study of midrotation-aged slash pine plantations were used to fit prediction equations for basal area, trees per acre, stand average dominant height, diameter distributions, and individual tree heights. The equations include N and P fertilizationrates and CRIFF soil groups as predictor variables. The survival model also accounts for the accelerating effect of fusiform rust on mortality rate. Using published tree volume equations, the prediction of volumes by dbh class for fertilized slash pine plantations is now possible. This integratedsystem of equations is available as a user-friendly computer program that can calculate expected yields by diameter class and aid the forester in evaluating investment opportunities that include forest fertilization. South. J. Appl. For. 13(2):76-80.


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