FLORISTIC DIVERSITY AND STRUCTURAL CHARACTERIZATION OF THE FOREST OF CHETTABA (ALGERIA)

2021 ◽  
Author(s):  
Zerrouki Alia ◽  
Kara Karima ◽  
Redjaimia Lilia ◽  
Rached-Kanouni Malika
Keyword(s):  
Management Strategies ◽  
Basal Area ◽  
Diversity Indices ◽  
Floristic Diversity ◽  
Stand Growth ◽  
Sustainable Resource Management ◽  
Forest Inventories ◽  
Dense Forest ◽  
North Algeria

"The structure of various stands, defined as the diversity of trees in the stands, can be an indication of overall biodiversity and habitat suitability, be useful in predicting stand growth and provide stand details for forest inventories. In an effort to find sustainable resource management strategies, a study was conducted on the structural and ecological characteristics of stands in Chettaba forest (Algeria). In this study, six diversity indices were used to characterize the horizontal and spatial distribution of individuals in multi-species stands, using four plots, located in the Chettaba forest (East-North Algeria). The results obtained allowed us to note that P2 and P3 present similar average densities (600 feet/ha), the plots P1 and P4 present low average densities (250 feet/ha and 350 feet/ha). The average DBH values vary from 25.65 cm for the P2 stand to 30.61 cm for the P1 stand. The average basal area varied between 33.73 m²/ha (P3) and 18.92 m²/ha (P1). The Shannon and Weaver index reached its maximum in plot 4 with 8 species. The study allowed us to evaluate the floristic diversity of the forest. Moreover, it indicated the need for its integral protection for its dynamics towards a dense forest vegetation."

scholarly journals Deriving Tree Size Distributions of Tropical Forests from Lidar

2021 ◽  
Vol 13 (1) ◽  
pp. 131
Author(s):  
Franziska Taubert ◽  
Rico Fischer ◽  
Nikolai Knapp ◽  
Andreas Huth
Keyword(s):  
Size Distribution ◽  
Spatial Scales ◽  
Basal Area ◽  
Tree Height ◽  
Tree Size ◽  
Diameter Distribution ◽  
Forest Inventories ◽  
Allometric Relations ◽  
Lidar Measurements ◽  
Derived Data

Remote sensing is an important tool to monitor forests to rapidly detect changes due to global change and other threats. Here, we present a novel methodology to infer the tree size distribution from light detection and ranging (lidar) measurements. Our approach is based on a theoretical leaf–tree matrix derived from allometric relations of trees. Using the leaf–tree matrix, we compute the tree size distribution that fit to the observed leaf area density profile via lidar. To validate our approach, we analyzed the stem diameter distribution of a tropical forest in Panama and compared lidar-derived data with data from forest inventories at different spatial scales (0.04 ha to 50 ha). Our estimates had a high accuracy at scales above 1 ha (1 ha: root mean square error (RMSE) 67.6 trees ha−1/normalized RMSE 18.8%/R² 0.76; 50 ha: 22.8 trees ha−1/6.2%/0.89). Estimates for smaller scales (1-ha to 0.04-ha) were reliably for forests with low height, dense canopy or low tree height heterogeneity. Estimates for the basal area were accurate at the 1-ha scale (RMSE 4.7 tree ha−1, bias 0.8 m² ha−1) but less accurate at smaller scales. Our methodology, further tested at additional sites, provides a useful approach to determine the tree size distribution of forests by integrating information on tree allometries.

Study of the floristic diversity of Acacia tortilis population- in Bechar region (Southwestern Algeria)

2019 ◽  
Vol 9 (4) ◽  
pp. 133-141
Author(s):  
Guenaia Abdelkader ◽  
Hasnaoui Okkacha ◽  
Bekkouche Assia
Keyword(s):  
Sustainable Use ◽  
Diversity Indices ◽  
Floristic Diversity ◽  
Acacia Tortilis ◽  
Important Species ◽  
Disturbance Index ◽  
Moricandia Arvensis ◽  
Biological Spectrum ◽  
Flora Diversity ◽  
Risk Loss

For the management and sustainable use of natural bio-resources it is necessary to quantify and valorize this heritage. In the case of the floristic diversity of Acacia tortilis, the only natural woody stand in Bechar-Algeria, scanty studies have been undertaken. Hence in this study, the general overview of the flora diversity state in the 58 plots of 9 stations was made by the analysis of various indexes: Shannon, Simpson, species evenness, floristic richness, disturbance index, biological and biogeographically spectra. We listed 103 species belonging to 37 families and 85 genus, the important plants belonged to the Asteraceae and Brassicaceae. The most important species are: Pulicaria crispa, Asteriscus graveolens, Launea arborescens, Matricaria pubescens, Moricandia arvensis, Farsetia aegyptiaca, Zilla macroptera. The biological spectrum indicated a dominance of the Chamaephytes and the predominance of the Therophytes; the phytogeographic spectrum showed an important endemism (44%) in which 36% species belong to the SaharoArabian element; The Shannon, Simpson, and Evenness diversity indices, were relatively high, thereby indicating a diversity variation between the stations, witch increased South towards North. It was prominent in Zouzfana, Taghit, and Abadla stations, and the higher values of disturbance Index reflected the greater level of anthropization in these courses. The future accumulation of this regression, many risk loss of the last naturally wall of desertification, biodiversity, national economy and sand advancement. Therefore, it is recommended to apply pastures protection, pastoral charge control, and elaborate an environmental value of this species. 

Sensitivity of C. fructicola and C. siamense of peach in China to multiple classes of fungicides and characterization of pyraclostrobin-resistant isolates

Plant Disease ◽  
2021 ◽  
Author(s):  
Hafiz Muhammad Usman ◽  
Qin Tan ◽  
Mohammad Mazharul Karim ◽  
Muhammad Adnan ◽  
Weixiao Yin ◽  
...  
Keyword(s):  
High Resistance ◽  
Mycelial Growth ◽  
Management Strategies ◽  
Cross Resistance ◽  
Qoi Fungicides ◽  
Quinone Outside Inhibitor ◽  
Dmi Fungicides ◽  
Colletotrichum Gloeosporioides Species Complex ◽  
Cyt B Gene

Anthracnose, mainly caused by Colletotrichum gloeosporioides species complex including C. fructicola and C. siamense, is a devastating disease of peach. The chemical control has been widely used for years and management failures have increased towards commonly used fungicides. Therefore, screening of sensitivity of Colletotrichum spp. to fungicides with different modes of action is needed to make proper management strategies for peach anthracnose. In this study, sensitivity of 80 isolates of C. fructicola and C. siamense was screened for pyraclostrobin, procymidone, prochloraz and fludioxonil based on mycelial growth inhibition at discriminatory doses. Results showed that C. fructicola and C. siamense isolates were highly resistant to procymidone and fludioxonil with 100% resistance frequencies to both fungicides, but sensitive to prochloraz, i.e., no resistant isolates were found. For pyraclostrobin, 74% of C. fructicola isolates showed high resistance and 26 % were low resistant, all of the C. siamense isolates were low resistant. No positive cross-resistance was observed between pyraclostrobin and azoxystrobin, even they are members of the same quinone outside inhibitor (QoI) fungicide group, and between pyraclostrobin and non-QoIs. Resistant isolates to QoI fungicides were evaluated for the fitness penalty. Results showed that no significant differences except for mycelial growth rates were detected between highly resistant and low-resistant isolates of C. fructicola. Molecular characterization of Cyt b gene revealed that the G143A point mutation was the determinant of the high resistance in C. fructicola. This study demonstrated the current resistance status of C. fructicola and C. siamense to different fungicides and their future perspectives. Demethylation inhibitor (DMI) fungicides are the best option among different chemicals to control peach anthracnose in China.

STRUCTURAL AND FLORISTIC CHARACTERIZATION OF THE OULED BECHIH FOREST (ALGERIA)

2021 ◽  
Author(s):  
Touafchia Boutheyna ◽  
Kadi Zahia ◽  
Redjaimia Lilia ◽  
Rached-Kanouni Malika
Keyword(s):  
Diversity Index ◽  
Basal Area ◽  
Woody Species ◽  
Quercus Suber ◽  
Average Density ◽  
Quercus Canariensis ◽  
Rational Management ◽  
Sustainable Conservation ◽  
Total Structure

The objective of this study is the rational management of forest ecosystems for sustainable conservation of floristic biodiversity. Two types of analysis are carried out: structural analysis and analysis of the main species. A total of 22 families were identified, divided among 32 species. The dominant woody species are Quercus suber and Quercus canariensis. Fagaceae is the most represented family. The average values of species richness and Shannon diversity index are 4 ± 1.8 and 0.9 ± 0.30 species/plot respectively. The average density of woody species in the Oueld Bechih forest was 158 ± 28 tree/ha with an average basal area of 32.67 ± 0.74m²/ha. The height structure shows that trees in height classes is ≥ 6 has very high density, evidence of almost no natural regeneration. The total structure indicates that larger trees are more abundant. In effect, this work provides a database for the forest, but it represents only one facet to be considered in protecting and restoring it.

Structure and Regeneration of Sal (Shorea robusta Gaertn. f.) Forests in Shiwalik Region of Kumaun Himalaya, India

2017 ◽  
Vol 40 (1) ◽  
pp. 1-8
Author(s):  
Bhawna Adhikari ◽  
◽  
Bhawana Kapkoti ◽  
Neelu Lodhiyal ◽  
L.S. Lodhiyal ◽  
...  
Keyword(s):  
Tree Species ◽  
Basal Area ◽  
Tree Canopy ◽  
Canopy Density ◽  
Kumaun Himalaya ◽  
Shorea Robusta ◽  
Canopy Trees ◽  
Dense Forest ◽  
Open Forest ◽  
Sal Forest

Present study was carried out to assess the structure and regeneration of Sal forests in Shiwalik region of Kumaun Himalaya. Vegetation analysis and tree canopy density was determined by using quadrat and densitometer, respectively. Density of seedlings, saplings and trees was 490-14067, 37-1233, and 273-863 ind.ha-1 respectively. The basal area was 0.12-5.44 m2 ha-1 reported for saplings and 25.4-77.6 m2 ha-1 for trees. Regeneration of Sal was found good in Sal mixed dense forest followed by Sal open forest and Sal dense forest, respectively. Regeneration of Sal was assisted by the presence of associated tree species as well as the sufficient sunlight availability on ground due to adequate opening of canopy trees in Sal forest. Thus it is concluded that the density of tree canopy, sunlight availability and also associated tree species impacted the regeneration of Sal in the region.

scholarly journals Zur Auswirkung der Hangneigungskorrektur auf Schätzwerte im Schweizerischen Landesforstinventar (LFI) | Investigation of the effect of the slope correction method as applied in the Swiss National Forest Inventory of estimates

2001 ◽  
Vol 152 (6) ◽  
pp. 215-225 ◽  
Author(s):  
Michael Köhl ◽  
Peter Brassel
Keyword(s):  
Forest Inventory ◽  
Basal Area ◽  
Correction Method ◽  
National Forest Inventory ◽  
National Forest ◽  
Average Deviation ◽  
Forest Inventories ◽  
Slope Correction ◽  
Number Of Stems ◽  
Elliptical Area

For forest inventories on slopes, it is necessary to correct the test areas, because the circular areas, when projected, become elliptical. Based on 93 samples from the Swiss National Forest Inventory (FNI), it was determined whether the simplified method, which increases the radius to match that of the elliptical area, leads to a distortion of the results. An average deviation of 2% was found between the FNI estimated values and the actual values for the basal area and the number of stems. For estimations of smaller units, greater distortions of the results are expected.

scholarly journals The effect of local land-use changes on floristic diversity during the past 1000 years in southern Sweden

The Holocene ◽  
2016 ◽  
Vol 27 (5) ◽  
pp. 694-711 ◽  
Author(s):  
Daniel Fredh ◽  
Florence Mazier ◽  
Petra Bragée ◽  
Per Lagerås ◽  
Mats Rundgren ◽  
...  
Keyword(s):  
Land Use ◽  
Time Windows ◽  
Land Use Changes ◽  
Management Strategies ◽  
Floristic Diversity ◽  
Southern Sweden ◽  
13Th Century ◽  
Land Use Pattern ◽  
Landscape Characteristics ◽  
Heterogeneous Landscape

The relationship between land-use and floristic diversity in the landscape, for the last millennia, is analysed from two small lakes in southern Sweden. Pollen analysis and the Local Vegetation Estimates (LOVE) model are used to quantify land-cover at local scales with 100-year time windows. Floristic richness is estimated using palynological richness, and we introduce LOVE-based evenness as a proxy for floristic evenness on a local scale based on the LOVE output. The results reveal a dynamic land-use pattern, with agricultural expansion during the 13th century, a partly abandoned landscape around AD 1400, re-establishment during the 15th–17th centuries and a transition from traditional to modern land-use during the 20th century. We suggest that the more heterogeneous landscape and the more dynamic land-use during the 13th–19th centuries were of substantial importance for achieving the high floristic diversity that characterises the traditional landscape. Pollen-based studies of this type are helpful in identifying landscape characteristics and land-use practices that are important for floristic diversity and may therefore guide the development of ecosystem management strategies aiming at mitigating the on-going loss of species seen in the landscape of southern Sweden and many other regions worldwide.

Characterization of microbial community in cold-chain hairtail fish by high-throughput sequencing technology

2021 ◽  
Author(s):  
Jiali Xing ◽  
Xiaorong Xu ◽  
Xiaohu Luo ◽  
Ruihang Zheng ◽  
Lingyan Mao ◽  
...  
Keyword(s):  
Microbial Community ◽  
High Throughput ◽  
High Throughput Sequencing ◽  
Bacterial Flora ◽  
Diversity Indices ◽  
Cold Chain ◽  
Class Level ◽  
The Family ◽  
Dominant Bacteria

Abstract: High-throughput sequencing was used to analyze the microbial communities in the muscle samples of hairtail fish to study their diversity and dynamic changes during cold-chain circulation. The results showed that the richness and diversity of the microbial community in hairtail fish had a transient decline in 0–24 h and decreased after the first rise during 24–216 h. The diversity and richness of bacteria in cold-chain hairtail fish reached the maximum at 168 h. The Shannon and Simpson diversity indices of the bacteria were 2.96 and 0.16, respectively, and their ACE and Chao1 richness indices were 254.84 and 155.10, respectively. In addition, the dominant bacteria were Proteobacteria in the phylum level, Gammaproteobacteria in the class level, Pseudomonadales in the order level, Pseudomonadaceae in the family level, and Pseudomonas in the genus level, and their relative abundance were 80.52%, 72.11%, 76.68%, 23.25%, and 53.50%, respectively. In this study, the structure of bacterial flora and the dominant bacteria in cold-chain hairtail fish were analyzed by high-throughput sequencing to provide a basis for exploring how to maintain the freshness of hairtail fish and for predicting the shelf-life of hairtail fish.

scholarly journals Bayesian Evaluation of Smartphone Applications for Forest Inventories in Small Forest Holdings

Forests ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1148
Author(s):  
Andrej Ficko
Keyword(s):  
Mobile Applications ◽  
Mobile Application ◽  
Basal Area ◽  
Small Enterprises ◽  
Private Forest ◽  
P Values ◽  
Forest Inventories ◽  
The Difference ◽  
Number Of Stems ◽  
Small Forest

There are increasingly advanced mobile applications for forest inventories on the market. Small enterprises and nonprofessionals may find it difficult to opt for a more sophisticated application without comparing it to an established standard. In a small private forest holding (19 ha, 4 stands, 61 standing points), we compared TRESTIMA, a computer vision-based mobile application for stand inventories, to MOTI, a smartphone-based relascope, in measuring the number of stems (N) and stand basal area (G). Using a Bayesian approach, we (1) weighted evidence for the hypothesis of no difference in N and G between TRESTIMA and MOTI relative to the hypothesis of difference, and (2) weighted evidence for the hypothesis of overestimating versus underestimating N and G when using TRESTIMA compared to MOTI. The results of the Bayesian tests were then compared to the results of frequentist tests after the p-values of paired sample t-tests were calibrated to make both approaches comparable. TRESTIMA consistently returned higher N and G, with a mean difference of +305.8 stems/ha and +5.8 m2/ha. However, Bayes factors (BF10) suggest there is only moderate evidence for the difference in N (BF10 = 4.061) and anecdotal evidence for the difference in G (BF10 = 1.372). The frequentist tests returned inconclusive results, with p-values ranging from 0.03 to 0.13. After calibration of the p-values, the frequentist tests suggested rather small odds for the differences between the applications. Conversely, the odds of overestimating versus underestimating N and G were extremely high for TRESTIMA compared to MOTI. In a small forest holding, Bayesian evaluation of differences in stand parameters can be more helpful than frequentist analysis, as Bayesian statistics do not rely on asymptotics and can answer more specific hypotheses.

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