scholarly journals TYPOLOGY, PRODUCTIVITY AND DYNAMICS OF ALEPPO PINE STANDS IN THE OUARSENIS MASSIF (ALGERIA)

AGROFOR ◽  
2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Mohamed SARMOUM ◽  
Rafael NAVARRO-CIRRILLO ◽  
Frederic GUIBAL ◽  
Fatiha ABDOUN

Aleppo pine is the most important forest species in Algeria. This species has been used for a long time in reforestation programs, notably the “green dam” planted in the 1970s. Despite this importance, the Aleppo pine continues to undergo all kinds of degradation such as land clearing, illegal cutting and fire. This situation is causing reduction of potential wood production, also jeopardizing the vitality of the stands and their regeneration. This work aims to describe the typology, productivity and dynamics of Aleppo pine stands in the Ouarsenis massif (West of Algeria). 27 plots were installed to describe the stands (composition of forest species, dbh , total height, and basal area). Regeneration was estimated by the rate of juvenile individuals (dbh5cm). The results obtained shows that the Aleppo pine develops different conditions for altitude, climate and type of soil. These conditions have a direct influence on the structure of the Aleppo pine and its productivity. The best populations develop on an average altitude (500 to 1400 m), in subhumid and semi-arid climates, on southern exposures and on limestone soils. The stands are mostly young (age 70 years) with good natural regeneration. These results put focus on the factors of degradation of the Aleppo pine, in particular the recurring fires and the lack of silvicultural management which application can improve the productivity and the vitality of the stands.

2020 ◽  
Vol 21 (6) ◽  
Author(s):  
Malika Rached Kanouni ◽  
Insaf Hani ◽  
Ratiba BOUSBA ◽  
Amina Beldjazia ◽  
Hichem KHAMAR

Abstract. Rached-Kanouni M, Hani I, Bousba R, Beldjazia A, Khammar H. 2020. Structural variability of Aleppo pine stands in two forests in northeastern Algeria. Biodiversitas 21: 2848-2853. The layout of the stand can be described as the width of the trees, their reciprocal locations, diametric distinction and height. The goal of this study is to recognize changes in the Pinus halepensis spatial and demographic systems in two Beni Oudjana and Chettaba Forests, located in northeast Algeria. An inventory of trees in these forest formations with P. halepensis dominance was carried out based on dendrometric parameters such as total height, tree diameter at dbh ≥ 5 cm, basal area, total volume, etc., as well as the number of trees in the forest. Tree diameter and height measurements were made on 12 rectangular plots (20 m × 20 m), located in both forests. The results obtained show that the mean stand density, mean diameter, basal area and total volume are higher in Chettaba Forest, the values attributed to these parameters are respectively (422 trees/ha, 27.07 cm, 26, 86 m2, 251.63 m3); while the total height and regeneration rate show significantly higher values in Beni Oudjana Forest (18.97 m, 607 individuals/ha). The structure in diameter and height of the species is bell-shaped to asymmetrically positive with a predominance of small diameter individuals in the Chettaba forest. On the other hand, in the Beni Oudjana Forest, the structure is ‘L’ shaped, showing a predominance of very small diameter individuals. These results indicate that the low regeneration rate of P. halepensis in the Chettaba Forest is due to anthropogenic pressures that favor the degradation of this forest.


1993 ◽  
Vol 58 ◽  
Author(s):  
D. Maddelein ◽  
J. Neirynck ◽  
G. Sioen

Mature  Scots pine (Pinus sylvestris  L.) stands are dominating large parts of the Flemish forest area. Broadleaved  species regenerate spontaneously under this pine canopy. This study studied  the growth and development of two planted pine stands with an older natural  regeneration, dominated by pedunculate oak (Quercus  robur L.), and discussed management options for  similar stands.     The results indicated a rather good growth of the stands, with current  annual increments of 5 m3.ha-1.yr-1. The pine overstorey is growing into valuable sawwood  dimensions, while the broadleaved understorey slowly grows into the  upperstorey. The quality of the regeneration is moderate but can be improved  by silvicultural measurements (pruning, early selection).     In both stands, an interesting (timber production, nature conservation)  admixture of secondary tree species is present in the regeneration. Stand  management is evolving from the classical clearcut system towards a  combination of a type of selection and group selection system.


1988 ◽  
Vol 53 ◽  
Author(s):  
C. De Schepper

The  study describes the natural regeneration state of a forest on coarse sandy  soils. The natural regeneration was studied in three different ecological  conditions: in 30 to 60 year old Scots pine stands, in a 62 year old mixed  stand of pedunculate oak and red oak, and on the free field.     The analysis of the regeneration groups revealed that the first settler  maintained a dominant social position during the following years after the  settlement. The structural basis is consequently laid out early. This means  that the forest practice has to consider the very first phase of the  regeneration as determining for the following evolution of the regeneration  groups.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tassiana Maylla Fontoura Caron ◽  
Victor Juan Ulises Rodriguez Chuma ◽  
Alexander Arévalo Sandi ◽  
Darren Norris

AbstractDegraded Amazonian forests can take decades to recover and the ecological results of natural regeneration are still uncertain. Here we use field data collected across 15 lowland Amazon smallholder properties to examine the relationships between forest structure, mammal diversity, regrowth type, regrowth age, topography and hydrology. Forest structure was quantified together with mammal diversity in 30 paired regrowth-control plots. Forest regrowth stage was classified into three groups: late second-regrowth, early second-regrowth and abandoned pasture. Basal area in regrowth plots remained less than half that recorded in control plots even after 20–25 years. Although basal area did increase in sequence from pasture, early to late-regrowth plots, there was a significant decline in basal area of late-regrowth control plots associated with a decline in the proportion of large trees. Variation in different forest structure responses was explained by contrasting variables, with the proportion of small trees (DBH < 20 cm) most strongly explained by topography (altitude and slope) whereas the proportion of large trees (DBH > 60 cm) was explained by plot type (control vs. regrowth) and regrowth class. These findings support calls for increased efforts to actively conserve large trees to avoid retrogressive succession around edges of degraded Amazon forests.


1982 ◽  
Vol 12 (2) ◽  
pp. 232-239 ◽  
Author(s):  
Chhun-Huor Ung ◽  
Jean Beaulieu ◽  
Daniel Demers

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.


2020 ◽  
Vol 21 (5) ◽  
Author(s):  
Malika Rached Kanouni ◽  
Alia ZERROUKI ◽  
Maroua LAHMAR ◽  
Amina Beldjazia ◽  
Karima Kara ◽  
...  

Abstract. Rached-Kanouni M, Zerrouki A, Lahmar M, Beldjazia A, Kara K, Ababsa. 2020. Assessment of the health status of the Sidi R'Ghies forest, Oum El Bouaghi, north-east Algerian. Biodiversitas 21: 1980-1988. In recent decades, the forest of Sidi R'Ghies has been degraded by human activity. The establishment of the state of the massif by a diagnosis on different forest plots is part of a project of monitoring and silvicultural management. The purpose of this study is to assess the health status of the Sidi R'Ghies forest. The methodology used was the visual assessment of the tree crown of the dominant species (i.e. Aleppo pine and holm oak) according to the protocols DEPEFEU, DEPERIS, and ICP Forests. These protocols were selected for adoption based on field observations and their applicability in record time. The results obtained indicate that the health status of the trees within the studied plots is declining. The DEPEFEU value index shows an average of 2.20 for Aleppo pine and 1.95 for holm oak while the DEPERIS has an average level of 4.56 in Aleppo pine and 3.07 in holm oak. ICP Forests has also contributed to providing clearer information on the consequences of this health situation by deducting an average visibility rate of 1.24 and 1.63; social status of 2.17 and 2.11 and competition of 1.71 and 2.49 for Aleppo pine and holm oak respectively. In general, the health status of the tree crown is average and almost adapted to the environmental conditions. In contrast, the carrying capacity of biodiversity is low and needs to be improved.


2021 ◽  
Vol 4 ◽  
Author(s):  
Sandra Cristina Müller ◽  
Rodrigo Scarton Bergamin ◽  
Kauane Maiara Bordin ◽  
Joice Klipel ◽  
Milena Fermina Rosenfield

Secondary forests originate from natural regeneration after fallow (succession) or restoration. Species assembly in these communities, which can affect ecosystem functions and successional trajectories, is very unpredictable. Trait-based trajectories can shed light on the recovery of ecosystem functions and enable predictions of how the regenerating communities will change with forest age. Regeneration communities are affected by initial conditions and also by canopy structure and functional traits that alter dispersers' attractiveness and coexistence mechanisms. Here we evaluated how community functional traits change over time and tested if functional diversity and composition of the established canopy, as well as the structure of the canopy and forest age, influence the functional structure of regenerating tree communities when compared to their reference forests. For this, we calculated dissimilarity in trait composition (community-weighted means) and in functional diversity of regenerating communities of each succession/restoration stand, using the tree stratum of nearby mature forests as baseline values. Functional trait information comprises leaf, wood density, and reproductive traits from tree species. Our community data contain information from natural successional forests and restoration sites, in the South-Brazilian Atlantic Forest. Predictor variables of functional dissimilarities were forest age, canopy structural variables, canopy functional composition, and functional diversity. Results showed leaf traits (leaf dry matter content, leaf nitrogen content, leaf nitrogen-phosphorus ratio) and seed mass varying with forest age. Canopy functional composition based on leaf traits and total basal area significantly predicted multiple trait functional dissimilarity between the regeneration component of secondary forests and their reference community values. Dissimilarity increased when the canopy was composed of species with more acquisitive traits. Difference in functional diversity was only influenced by forest age. Mid-stage secondary forests showed lower functional diversity than early-stage forests. Our results indicated the importance of canopy traits on the natural regeneration of secondary subtropical forests. If functional similarity with reference forests is a desired objective in order to recover ecosystem functions through natural regeneration, leaf functional traits of canopy trees that establish or are planted in degraded areas must be considered in the successional processes.


1996 ◽  
Vol 23 (2) ◽  
pp. 185 ◽  
Author(s):  
SA Munks ◽  
R Corkrey ◽  
WJ Foley

The distribution of the koala (Phascolarctos cinereus) and the common brushtail possum (Trichosurus vulpecula) within the Prairie-Torrens Creek Alluvials province of the Desert Upland region of north-western Queensland was examined. The optimum habitat for each species as indicated by the occurrence of faecal pellet groups was found to be that associated with creek-lines. However, other land types were also used by each species to varying degrees. The relationship between various habitat variables and pellet group counts was investigated using Multiple regression and a Generalised linear model. Proximity to creek-bed, total basal area of trees, species richness and Acacia basal area (negative) best explained the occurrence of koalas. Proximity to creek-bed, Acacia basal area (negative), total basal area of trees, and available water (negative) best explained the occurrence of brushtail possums. In contrast to studies of arboreal species in the moist-south-eastern forests of Australia no relationship was found between foliar nutrient concentrations and the occurrence of koalas or brushtail possums. However, a significant relationship was found between leaf water concentration and the occurrence of koalas. It is suggested that water availability is the paramount factor defining preferred arboreal habitat in arid and semi-arid woodlands.


2007 ◽  
Vol 24 (1) ◽  
pp. 65-70 ◽  
Author(s):  
Matthew J. Duveneck ◽  
William A. Patterson

Abstract Destructive sampling of 31 pitch pine (Pinus rigida P. Mill) trees ranging in dbh from 2.7 to 42.5 cm and in height from 4.1 to 23.8 m provided a complete inventory of needles and small-diameter branch weights used to characterize canopy fuels to predict fire behavior in pitch pine stands. Regression equations using dbh as an independent variable predict canopy bulk density with an r2 > 0.93. The results provide managers with a method of evaluating the effectiveness of thinning operations in reducing crown fire potential in well-stocked stands. To demonstrate the application of the method, we calculated the wind speed (Crowning Index [CI]) needed to sustain an active crown fire in thinned and unthinned pitch pine stands in Montague, Massachusetts. Thinning to 2.8 m2/ha basal area increased the CI from 34 to 98 km/hour.


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