scholarly journals STRUCTURAL AND DYNAMIC CHANGES IN MIXED FORESTS OF BEECH AND FIR ON MT. GOČ

2020 ◽  
Vol 1 (28) ◽  
Author(s):  
Snežana Obradović ◽  
Damjan Pantić ◽  
Milan Medarević ◽  
Biljana Šljukić ◽  
Biljana Pešić
Keyword(s):  
Basal Area ◽  
High Volume ◽  
Dynamic Changes ◽  
Mixed Forests ◽  
Permanent Sample Plots ◽  
Selection Cutting ◽  
Regulatory Processes ◽  
Management Procedures ◽  
Selection Forest ◽  
The Right

The primary goal of this research was to analyze the structural, production and dynamic changes of theforests of beech and fir in permanent sample plots of Mt. Goč, excluded from regular management fora period of 35 years (1977–2011). The established principles of spontaneous development and selfregulatoryprocesses could have implications on the regular management in these forests located in thearea of Mt. Goč and other areas.The results of this research in the permanent sample plots indicate that the mixed forests of beech andfir have suffered a number of changes in terms of structure and production in the investigated period.Structural disruptions have been the result of a decrease in the share of small and medium-diametertrees, as well as an increase in the share of trees of large dimensions in the total number of trees. Thecurves of distribution have been moved to the right and in terms of shape they differ from the lines thatare typical of selection forests. A relatively large number of trees per hectare and the described distributionby diameter classes have resulted in the high values of basal area and stand volume. In addition,a high volume increment has also been recorded. The quality and incremental capacity of the standshave been reduced due to a significant share of old beech and fir trees. The accumulation of volumeslowed down the dynamics of stand development and hindered rejuvenation and recruitment, as thenecessary prerequisites for structural stability and functionality in selection forests.The observed trends of development in these forests in the sample plots clearly indicate that a structurallystable, socio-economically and ecologically valuable selection forest is possible to achieve only withan active and continuous implementation of a set of management procedures, which primarily refersto selection cutting. Self-regulatory processes that are allowed over time, as in the case of the analyzedsample plots, are increasingly distancing us from this goal.

Selection cutting in over-mature spruce–fir stands in Quebec

1976 ◽  
Vol 6 (1) ◽  
pp. 69-77 ◽  
Author(s):  
G. F. Weetman ◽  
D. Algar
Keyword(s):  
Black Spruce ◽  
Volume Growth ◽  
Basal Area ◽  
Valley Bottom ◽  
Permanent Sample Plots ◽  
Selection Cutting ◽  
Logging Damage ◽  
The North ◽  
Straight Line ◽  
St Lawrence River

On the North Shore of the St. Lawrence River in the boreal forest (Forest Section B.1b) there are extensive stands of old-growth black spruce (Piceamariana (Mill.) B.S.P.) and balsam fir (Abiesbalsamea (L.) Mill.). They grow on high-quality valley-bottom sites with a diameter class distribution that is close to the theoretical ideal of the straight-line log relationship considered ideal for selection forests.In 1962, two stands containing about 3500 ft3/acre (246 m3/ha) on 36 acres (14.5 ha) were cut to remove between 20% and 50% of the volume in the form of a selection cut. Basal area and volume, growth, ingrowth, mortality, logging damage, and blowdown losses were monitored in two 5-year remeasurements on a network of 72 permanent sample plots. Only 18 of these plots showed a net loss in basal area for the 10-year period after treatment.It is concluded that in sheltered locations it could be possible to maintain stands such as these in a productive and aesthetically pleasing condition by careful selection cutting.

Contribution to the automation of the calculations involving the forest inventory with the aid of an office computer

1970 ◽  
Vol 20 ◽  
Author(s):  
R. Goossens
Keyword(s):  
Tree Species ◽  
Forest Inventory ◽  
Basal Area ◽  
Annual Increment ◽  
Mixed Stands ◽  
Mean Values ◽  
Standing Trees ◽  
General Program ◽  
Magnetic Card ◽  
The Right

Contribution to the automation of the calculations involving  the forest inventory with the aid of an office computer - In this contribution an attempt was made to perform the  calculations involving the forest inventory by means of an office computer  Olivetti P203.     The general program (flowchart 1), identical for all tree species except  for the values of the different parameters, occupies the tracks A and B of a  magnetic card used with this computer. For each tree species one magnetic  card is required, while some supplementary cards are used for the  subroutines. The first subroutine (flowchart 1) enables us to preserve  temporarily the subtotals between two tree species (mixed stands) and so  called special or stand cards (SC). After the last tree species the totals  per ha are calculated and printed on the former, the average trees occuring  on the line below. Appendix 1 gives an example of a similar form resulting  from calculations involving a sampling in a mixed stand consisting of Oak  (code 11), Red oak (code 12), Japanese larch (code 24) and Beech (code 13).  On this form we find from the left to the right: the diameter class (m), the  number of trees per ha, the basal area (m2/ha), the current annual increment  of the basal area (m2/year/ha), current annual volume increment (m3/year/ha),  the volume (m3/ha) and the money value of the standing trees (Bfr/ha). On the  line before the last, the totals of the quantities mentioned above and of all  the tree species together are to be found. The last line gives a survey of  the average values dg, g, ig, ig, v and w.     Besides this form each stand or plot has a so-called 'stand card SC' on  wich the totals cited above as well as the area of the stand or the plot and  its code are stored. Similar 'stand card' may replace in many cases  completely the classical index cards; moreover they have the advantage that  the data can be entered directly into the computer so that further  calculations, classifications or tabling can be carried out by means of an  appropriate program or subroutine. The subroutine 2 (flowchart 2) illustrates  the use of similar cards for a series of stands or eventually a complete  forest, the real values of the different quantities above are calculated and  tabled (taking into account the area). At the same time the general totals  and the general mean values per ha, as well as the average trees are  calculated and printed. Appendix 2 represents a form resulting from such  calculations by means of subroutine 2.

Modèle de prédiction des essences feuillues et résineuses du Québec

1982 ◽  
Vol 12 (2) ◽  
pp. 232-239 ◽  
Author(s):  
Chhun-Huor Ung ◽  
Jean Beaulieu ◽  
Daniel Demers
Keyword(s):  
Prediction Model ◽  
Basal Area ◽  
Growth Conditions ◽  
The State ◽  
Department Of Energy ◽  
Forest Species ◽  
Permanent Sample Plots ◽  
Real Growth ◽  
Basic Characteristics ◽  
Softwood Species

This paper describes a prediction model adopted by the Department of Energy and Resources of Quebec to (i) update temporary sample plots and (ii) project into the future the state of permanent sample plots in Quebec forests. Predicting the growth of a forest species means predicting the state of this species in time. Three basic characteristics mark the state of a species in a given year: number of trees, their total basal area, and their total volume. To date, in Quebec, normal or empirical yield tables have been used to predict the state of some species in ideal or real growth conditions, but these yield tables apply only to pure or almost pure even-aged stands. The prediction model for hardwood and softwood species presented in this paper serves the same purpose as the yield tables; however, it differs from the yield tables in that it can predict the state of each hardwood or softwood species found in pure or mixed, even- or uneven-aged stands. The prediction model was validated for 19 species found in a pilot territory located in the Basse-Gatincau (southwestern Quebec). The paper terminates with a discussion on the limitation of the prediction model and the conditions for its use.

Present-day expansion of American beech in northeastern hardwood forests: Does soil base status matter?

2009 ◽  
Vol 39 (12) ◽  
pp. 2273-2282 ◽  
Author(s):  
Louis Duchesne ◽  
Rock Ouimet
Keyword(s):  
Acer Saccharum ◽  
Sugar Maple ◽  
Basal Area ◽  
Base Cation ◽  
Hardwood Forests ◽  
Fagus Grandifolia ◽  
Soil Base ◽  
Large Area ◽  
American Beech ◽  
Permanent Sample Plots

Recently, sugar maple ( Acer saccharum Marsh.) decline in northeastern North America has been regarded as a major factor structuring hardwood forests by favouring American beech ( Fagus grandifolia Ehrh.) in the understory of maple-dominated stands. To determine whether soil fertility differences associated with sugar maple decline may have promoted the expansion of American beech, we explored the relationships between the soil base status and the sapling and tree strata density and composition, using data from 426 permanent sample plots distributed throughout Quebec. Our results indicate that American beech is currently expanding in the sugar maple range of Quebec. The abundance and proportion of American beech in the sapling stratum are mainly associated with the proportion of American beech in the tree stratum, the relative basal area of dead sugar maple trees, and the base status of soils. In accordance with the many studies reporting on the high sensitivity of sugar maple to the acid–base status of soils and the decline of the sugar maple population, this study supports the hypothesis that soil base cation depletion, caused in part by atmospheric acid deposition, is among the main factors involved in the present-day expansion of American beech over a large area in Quebec.

Canada's oldest permanent sample plots — thinning in white and red pine

1998 ◽  
Vol 74 (4) ◽  
pp. 606-616 ◽  
Author(s):  
Darwin Burgess ◽  
Craig Robinson
Keyword(s):  
Woody Debris ◽  
Basal Area ◽  
Wildlife Habitat ◽  
Red Pine ◽  
Major Influence ◽  
Residual Volume ◽  
Annual Increment ◽  
Permanent Sample Plots ◽  
Stand Management ◽  
Set Up

Two of the oldest permanent sample plots (PSPs) in Canada were set up at Petawawa, Ontario (45° 57′ N, 77° 34′ W) to examine the effect of thinning on the development of natural white (Pinus strobus L.) and red pine (Pinus resinosa Ait). Field data were collected periodically, starting in 1918 when the stand was 40 years old and continuing for 71 years. Six thinning treatments were completed, beginning in 1918, and then in 1933, 1941, 1959, 1969 and 1989. The intensity of thinning varied through time with 14, 27, 38, 8, 30, and 7% of the basal area removed. The sawlog volume mean annual increment for the thinned plot remained stable at about five m3 ha−1 yr−1, but the sawlog volume periodic annual increment for the control declined markedly during the last 10-year measurement period to less than 2 m3 ha−1 yr−1. The residual volume was higher in the control; but, if the harvested sawlog volume (264.5 m3 ha−1) was added to the residual sawlog volume (301.3 m3 ha−1) for PSP one, then the sawlog production on the thinned plot has been about the same and its residual volume concentrated on fewer, larger and more valuable trees. The level of natural mortality in the control plot (129.7 m3 ha−1 of sawlog volume) was greater than 10 times that in the thinned plot, thereby adding more coarse woody debris to improve wildlife habitat. These two approaches had a major influence on stand development. The approach used will depend on specific stand-level management objectives. Key words: white pine, red pine, natural stand management, shelterwood system, permanent sample plots.

Tracking the Formation and Degradation of Fatty-Acid-Accumulated Mitochondria Using Label-Free Chemical Imaging

2020 ◽  
Author(s):  
Chi Zhang ◽  
Stephen Boppart
Keyword(s):  
Fatty Acid ◽  
Structural Features ◽  
Chemical Imaging ◽  
Live Cells ◽  
Label Free ◽  
Dynamic Changes ◽  
Regulatory Processes ◽  
Transport Chain ◽  
Anti Stokes ◽  
First Time

Abstract The mitochondrion is one of the key organelles for maintaining cellular homeostasis. External environmental stimuli and internal regulatory processes alter the metabolism and functions of mitochondria. To understand these activities of mitochondria, it is critical to probe the key metabolic molecules inside these organelles. In this study, we used label-free chemical imaging modalities including coherent anti-Stokes Raman scattering and multiphoton-excited autofluorescence to study the mitochondrial activities in living cancer cells. We found that hypothermia exposure tends to induce fatty-acid (FA) accumulation in some mitochondria of MIAPaCa-2 cells. Autofluorescence images show that the FA-accumulated mitochondria also have abnormal NADH and FAD metabolism, likely induced by the dysfunction of the electron transport chain. We also found that when the cells were re-warmed to physiological temperature after a period of hypothermia, the FA-accumulated mitochondria changed their structural features, likely caused by the mitophagy process. To the best of our knowledge, this is the first time that FA accumulation in mitochondria was observed in live cells. Our research also demonstrates that multimodal label-free chemical imaging is an attractive tool to discover abnormal functions of mitochondria at the single-organelle level and can be used to quantify the dynamic changes of this organelle under perturbative conditions.

scholarly journals Stand-Level Components of a Growth and Yield Model for Nothofagus Mixed Forests from Southern Chile

Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 810
Author(s):  
Sebastian Palmas ◽  
Paulo C. Moreno ◽  
Wendel P. Cropper ◽  
Alicia Ortega ◽  
Salvador A. Gezan
Keyword(s):  
Forest Type ◽  
Geographical Area ◽  
Basal Area ◽  
Forest Growth ◽  
Model Systems ◽  
Growth And Yield ◽  
Permanent Plots ◽  
Stand Age ◽  
Yield Model ◽  
Mixed Forests

Reliable information on stand dynamics and development is needed to improve management decisions on mixed forests, and essential tools for this purpose are forest growth and yield (G&Y) models. In this study, stand-level G&Y models were built for cohorts within the natural mixed second-growth Nothofagus-dominated forests in Chile. All currently available (but limited) data, consisting of a series of stratified temporary and permanent plots established in the complete range of this forest type, were used to fit and validate these models. Linear and nonlinear models were considered, where dominant stand age, number of trees, and the proportion of basal area of Nothofagus species resulted in significant predictors to project future values of stand basal area for the different cohorts (with R2 > 0.51 for the validation datasets). Mortality was successfully modeled (R2 = 0.79), based on a small set of permanent plots, using the concept of self-thinning with a proposed model defined by the idea that, as stands get closer to a maximum density, they experience higher levels of mortality. The evaluation of these models indicated that they adequately represent the current understanding of dynamics of basal area and mortality of Nothofagus and companion species in these forests. These are the first models fitted over a large geographical area that consider the dynamics of these mixed forests. It is suggested that the proposed models should constitute the main components of future implementations of G&Y model systems.

scholarly journals EFEITO DA EXPLORAÇÃO DE IMPACTO REDUZIDO EM ALGUMAS ESPÉCIES DE SAPOTACEAE NO LESTE DA AMAZÔNIA

FLORESTA ◽  
2013 ◽  
Vol 43 (3) ◽  
pp. 395 ◽  
Author(s):  
Leonardo Pequeno Reis ◽  
José Natalino Macedo Silva ◽  
Pamella Carolline Marques Dos Reis ◽  
João Olegário Pereira de Carvalho ◽  
Waldenei Travassos de Queiroz ◽  
...  
Keyword(s):  
Rain Forest ◽  
Basal Area ◽  
Tree Density ◽  
The Other ◽  
Permanent Sample Plots ◽  
Structure And Dynamics ◽  
The Family ◽  
Commercial Species ◽  
Three New Species ◽  
Reduced Impact Logging

Avaliou-se o efeito da exploração de madeira, realizada em 1997, na estrutura e dinâmica de algumas espécies de Sapotaceae em uma Floresta Ombrófila Densa, no município de Moju, Pará (02º12’26”S e 48º48’14”W). De uma área de floresta de 1.050 ha, foram selecionados 200 hapara exploração seletiva de intensidade de 23 m3.ha-1. Nessa área, foram alocadas 22 parcelas permanentes de 0,5 ha, totalizando 11 ha amostrais, onde foram medidas todas as árvores com DAP ≥10 cm, nos anos de 1995 (antes da exploração), 1998 e 2010 (após exploração). Os parâmetros avaliados foram densidade (Da) e área basal (m2.ha-1). No período de 1995 a 2010, Sapotaceae apresentou uma redução significativa de 7,7% na densidade (p = 0,0147) e aumento na dominância em 1,4% (p = 0,7851). Nesse mesmo período, observou-se redução da densidade e dominância para Pouteria laurifolia (Gomes) Radlk. (66,7 e 50,6%), Pouteria macrocarpa (Mart.) D. Dietr. (25 e 29,4%), Micropholis acutangula (Ducke) Eyma (20 e 11%), Manilkara huberi (Ducke) A. Chev. (16,4 e 17,7%) e Manilkara paraensis (Huber) Standl. (12,5 e 31,4%). A espécie com maior valor comercial, M. huberi, não mostrou recuperação nesse parâmetro, porém houve ingresso de três novas espécies na população de Sapotaceae estudada.AbstractEffect of reduced impact logging in some sapotaceae species in the eastern amazon. Effect of logging, held in 1997, on structure and dynamics of some Sapotaceae species were evaluated in a dense tropical rain forest located in the municipality of Moju, Pará (02º 12’ 26” S e 48º 48’ 14” W). Two hundred ha out of 1,050 ha forest area were selectively logged for timber (23 m3ha-1 logging intensity) in 1997.Twenty-two 0.5 ha permanent sample plots (11 ha sample) were established and all trees with dbh ≥ 10 cm were identified and measured for dbh in 1995 (before logging), 1998 and 2010 (after logging). Parameters evaluated were Density (De) and Basal area (G-m2 ha-1). Sapotaceae presented a significant reduction of 7.7% on tree density (p=0.0147), and an dominance increase of 1.4% (p=0.7851). In the same period, decreases in density and basal area were observed to Pouteria laurifolia (Gomes) Radlk. (66.7 and 50.6%), Pouteria macrocarpa (Mart.) D. Dietr. (25 and 29.4%), Micropholis acutangula (Ducke) Eyma (20 and 11%), Manilkara huberi (Ducke) A. Chev. (16.4 and 17.7%) and Manilkara paraensis (Huber) Standl. (12.5 and 31.4%). The main commercial species M. Huberi did not recover its original density. On the other hand, three new species of the family were recorded in the focused period.Keywords: Forest management; Pouteria; Manilkara; Amazonian Forest.

In Vivo MR Studies of Dynamic Changes in the Interosseous Membrane of the Forearm During Rotation

1999 ◽  
Vol 24 (2) ◽  
pp. 245-248 ◽  
Author(s):  
T. NAKAMURA ◽  
Y. YABE ◽  
Y. HORIUCHI
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Interosseous Membrane ◽  
Resonance Imaging ◽  
Forearm Rotation ◽  
Dynamic Changes ◽  
Magnetic Resonance Imaging Mri ◽  
Membranous Part ◽  
The Right

In vivo dynamic changes in the interosseous membrane (IOM) during forearm rotation were studied using magnetic resonance imaging (MRI). The right forearms of 20 healthy volunteers were examined in five different rotational positions. Axial slices were obtained at the proximal quarter, the middle and the distal quarter of the forearm. The changes in shape of the IOM during rotation were observed in an axial MR plane. For each image, we measured the interosseous distance and the length of the interosseous membrane. Images of the tendinous and membranous parts of the IOM could be differentiated by thickness. There were minimal dynamic changes in the tendinous part on the MRI while the membranous part showed numerous changes during rotation. The interosseous distance and the length of the interosseous membrane were maximum from a neutral to a slightly supinated position. The tendinous part is considered to be taut during rotation to provide stability between the radius and the ulna, but the membranous part which is soft, thin and elastic, allows smooth rotation.

P2848Electrical reconnections after pulmonary vein isolation with or without contact force-guided catheters: a comparison of the proficiency of atrial fibrillation ablation

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
Y Fujimoto ◽  
K Yodogawa ◽  
Y Iwasaki ◽  
M Hachisuka ◽  
R Mimuro ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Pulmonary Vein ◽  
Contact Force ◽  
High Volume ◽  
Procedure Time ◽  
Surgical Ablation ◽  
Af Ablation ◽  
Significant Difference ◽  
The Right ◽  
Posterosuperior Segment

Abstract Background Atrial fibrillation (AF) ablation is the most commonly performed catheter ablation (CA) procedure today. The 2015 ACC/AHA/HRS Advanced Training Statement reported that the success rate of AF ablation is higher in high-volume centers than in low-volume centers. We tested whether the procedure proficiency of each operator was associated with the outcome of AF ablation, and whether the ablation outcome depended on whether contact force (CF)-guided catheters were used or not, in a high-volume center. Methods We conducted a retrospective observational study including all AF patients who underwent radiofrequency CA with or without CF support since 2016 at our hospital. The patients who underwent CA at other hospitals or underwent a balloon or surgical ablation in the first session were excluded. Each ipsilateral pulmonary vein (PV) pair was divided into 8 segments. The reconnection numbers and sites of the PV segment were evaluated in the second session. Operators were divided into the experienced group (≥100 AF cases/year, at least every 3 years) and developing group (other than the experienced group), respectively. Results Among 728 patients who underwent an initial AF ablation and were followed for 510±306 days, 131 (90 males, 65±10 years) received a second ablation procedure and were analyzed. A total of 260 and 264 PV isolations (PVI) were performed by the experienced and developing group operators in the initial ablation, respectively. Compared to the experienced group, the developing group had a longer procedure time for the PVI (35±15 vs. 28±10 min, p<0.001), higher frequency of reconnections of the PVs (73% vs. 59%, p=0.01) and higher number of reconnection gaps (2.1±2.0 vs. 1.5±2.0, p=0.02), respectively. There were no significantly differences in the number of gaps between the catheters with and without CF (1.6±2.0 vs. 1.4±2.0, p=0.65) in the experienced group, however, in the developing group a smaller total number of gaps (1.5±1.6 vs. 2.4±2.1, p=0.006) and less frequency reconnection gaps of the posterosuperior segment of the right PV (10% vs. 45%, p=0.005) were seen with catheters with CF than without. There was no significant difference in the procedure time for the PVI between catheters with and without CF. Conclusions The operator proficiency may predict the outcome after AF ablation even in high-volume centers. It is preferable to perform PVI with a CF-sensing catheter for operators without adequate proficiency. Acknowledgement/Funding JSPS KAKENHI Grant Number JP18K15865

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