Importance Value Index Research Articles

Structural characterization and species composition of mangrove vegetation in Lhokseumawe, Indonesia: Insight from multivariate analysis

The structure of the plant community significantly influences the equilibrium of the surrounding environment, affecting the trophic interactions within its ecosystem. The investigation of mangrove vegetation in Cut Mamplam village was carried out in September 2021 to determine the condition and structural characteristics of the mangrove ecosystem by multivariate analysis. The mangrove vegetation in Cut Mamplam Village was sampled at three observation stations by establishing a transect parallel to the coast. Subsequently, the community structure was examined and assessed using cluster analysis and nonmetric multidimensional scaling using the PRIMER v7 software. The study findings indicate that the mangrove forest vegetation in Cut Mamplam Village consists of five species from three families. Avicennia alba, A. lanata, Bruguiera gymnorrhiza, Rhizophora mucronata and Sonneratia alba. The highest density of mangrove vegetation was observed in A. alba in all categories: trees (616.67 ind/ha), seedlings (833.33 ind/ha) and saplings (66666.67 ind/ha). Additionally, the highest important value index (IVI) was recorded in A. alba for all categories: trees (232.16%), seedlings (102.40%), and saplings (228.43%). A similarity of mangrove density between species was noted at 60%, resulting in the formation of two distinct groups. Regarding the basal area, the vegetation stands of A. alba and A. lanata exhibited the highest values (280.61 and 266.03 m2/ha, respectively). The similarity of basal area among the observed species was 20%, resulting in the formation of two distinct groups. Additionally, Station II, classified as having mature vegetation, demonstrated a maturity similarity of 80% between observation stations.

Investigation on possibility of mangrove regeneration: a case study from Indian Sundarbans.

Mangroves serve as biotic fences of estuarine belts consisting of salt-tolerant plants that grow in intertidal zones and can be regenerated naturally as well as artificially. Mangrove regeneration refers to the process of restoring or rebuilding mangrove ecosystems that have been already degraded, damaged, or lost from their native place through the monitoring of geomorphological, taxonomical, pedological, and ecological aspects. The primary objective of this study was based on the remote sensing application through several important health monitoring indices over the minute part of Indian Sundarbans to prove the possibility of mangrove regeneration. Change detection analysis in the indices proves that there was possible growth and development in mangrove colonization over the same. The secondary objective is to comprehend the association of field-related study with the remotely sensed data on species diversity assessment over the same where the native species are Avicennia marina (Peyara Bain), Avicennia officinalis (Jat Bain), Avicennia alba (Kalo Bain), Aegialitis rotundifolia (Tora), Acanthus ilicifolius (Horgoj Kanta), Bruguiera gymnorrhiza (Kankra), Ceriops tagal (Goran), and Aegiceras corniculatum (Khalisi). The latter objective is associated with the tertiary one that unveils the correlation between several physico-chemical properties of soil samples taken from the field with the species accommodation.Textural classes are grouped between clay and silty clay that helps to get the foundation of hard wood-basedspecies (Avicennia type) specifically with the salinity ranges between 200 ppt (Site 2) and 633 ppt (Site 1)approximately which presents that the zone is highly saline zone as specifically Avicennia species can sustain highsalinity. Importance Value Index (IVI) and species diversity indices have been run to support whether the zone is diversified or not.Equilibrium between deforestation and regeneration through mangrove plantation has to be attained in the nearfuture as deforestation for the livelihood purposes exists, so this newly born island locally named Dorabagdamangrove patch, upper part (Gopalganj) of Kaikhali village, would be the best experimental study site on mangroveregeneration.

Wind turbine energy forecasting using real wind farm’s measurement data and performance of gene expression programming analytical model in comparison to traditional algorithms

ABSTRACT Forecasting wind power is vital to ensure steady, sustainable, and renewable energy. The complex nonlinear nature of wind flow and its interrelated factors make power prediction challenging. This study predicted wind power curves inspired by the Biologically Inspired Evolutionary Computation (BIEC) paradigm, incorporating Gene Expression Programming (GEP), Artificial Neural Networks (ANN), Least Square Support Vector Machines (LSSVM), and Random Forest (RF) models. Key input parameters include wind speed, yaw azimuth, turbulent intensity, veer, horizontal and vertical shear, ambient temperature, blade pitch, and rotor speed. The study evaluates these models’ effectiveness using root mean square error (RMSE) and correlation coefficient R. Results indicate that the GEP model offers transparent modeling, emphasizing critical inputs like wind speed, rotor speed, blade pitch angle, and temperature for wind power prediction. The GEP model identified wind speed, rotor speed, blade pitch angle, and temperature as the most influential parameters, with variable importance index (Ii) values of 69.39%, 24.39%, 5.46%, and 0.64% for training, and 69.37%, 25.03%, 4.98%, and 0.54% for validation. The study demonstrates the GEP model’s efficacy in accurately forecasting wind power curve, achieving a high correlation with training and validation coefficients of 0.9899 and 0.994, respectively, outperforming traditional models with minor errors.

Kawí Tamiruyé: a permanent research forest plot in the Sierra Tarahumara

This study characterizes the dasometric and structural parameters of a permanent research plot in northern Mexico. From a total census, 2165 trees (n) were recorded in an area of 1.4 ha-1 and, through the application of various sampling schemes, dasometric variables, and diversity indices were estimated for comparison with the census of a reference plot. We calculated the following dasometric measurements, Quadratic Mean Diameter (QMD)= 12.16 cm, Crown Area (CA)= 61.6%, Reineke's Stand Density Index (SDI)= 668 individuals, Basal Area (BA)= 25.16 m2, Total Volume (Vol)= 158.83 m3 ha-1, aboveground biomass (AGB= 142.78 Mg ha-1) and Carbon (C= 71.39 Mg ha-1). Ecologically, the species with the highest importance value index (IVI) were P. engelmannii and J. deppeana (50.8% and 35%, respectively). The Simpson's dominance index (δ)= 0.39 and diversity (λ)= 0.61 were low, as was the Shannon-Weaver index of diversity (H'= 1.3), which is in agreement with the Margalef index (DMg= 1.04). The value of Pielou's evenness (J'= 0.53) confirmed low abundance. Equidistant systematic sampling at 40 m was closer to the reference census, presenting lower values in the mean and variance estimators compared to the other sampling methods. The results can be included in management portfolios to improve decision-making. Although further studies on site size, inclusion of additive indices, and operational costs are required.

Macrophyte Diversity and Ecosystem Services in Wetlands of Eastern Ranchi: A Multi-site Analysis of Abundance, Frequency, and Importance Value Index Patterns

Macrophytes, visible aquatic and semi-aquatic plants, are integral components of wetland ecosystems, playing crucial roles in maintaining biodiversity, providing ecosystem services, and ensuring ecological stability. This research examines the distribution, abundance, frequency, diversity, and ecosystem services of macrophytes in several wetlands (W1-W7) located in the eastern part of Ranchi district, Jharkhand, India. The study sites include Bundu Lake, Hindalco Pond, Choga Bada Talab, Raja Bandh, Kita Uparbandh, Tamar Bada Talab, and Rukka Dam. A quantitative assessment using quadrat sampling and phytosociological methods was conducted from September 2022 to March 2023 to ensure accurate data collection and analysis. The study documented 78 macrophyte species belonging to 33 families and 58 genera. Emergent macrophytes were found to be the dominant life form, constituting 69% of the recorded species. Several species demonstrated high frequency and abundance across multiple study sites, including Pontederia crassipes Mart., Alternanthera philoxeroides (Mart) Griseb., Hydrilla verticillata (L.f.) Royle, Ipomoea aquaticaForssk., and Nymphoides hydrophyllum (Lour.) kuntze. To assess the diversity and ecological characteristics of the macrophyte communities, various diversity indices were calculated. These included the Shannon-Wiener index, Simpson's index, Margalef index, and Pielou's Evenness index. The results of these analyses revealed high levels of macrophyte diversity and evenness within the studied wetlands. Twenty-one macrophytes were identified as key species and nine species as rare species based on their IVI (Importance Value Index) scores. The key species were found to provide essential ecosystem services, including erosion control, water quality improvement, nutrient cycling, carbon sequestration, and habitat provision for other organisms. This research contributes significantly to our understanding of macrophyte diversity patterns and traits-based ecosystem services in wetland ecosystems. The findings of this study have important implications for the development and implementation of effective conservation strategies for these vital wetland ecosystems in the eastern Ranchi (W1- W7).

Assessment of diversity of plant species, composition, structure and regeneration status in Gondar Zuria District, Ethiopia

This study assesses the composition, arrangement, and state of regeneration in Gondar Zuria District. The two transect lines over the gradient were set up using a systematic random sample strategy in order to gather the number of species and their diameter for tree species in DBH (cm). The distance between the sample plots was 50 m, and the transect lines were 50 m apart. 12 circular plots were used in the total sample area of the botanical garden, and the sizes of the circular plots were 6.5 m for trees, 4.5 m for saplings, and 2.5 m for seedlings. Using the important value index and the diameter at breast height, the pattern of plant structure displays an inverted J shape. A review of the botanical garden’s plant species’ regeneration status revealed that, of the tree and shrub species, 6.25% had fair regeneration status and 25% had poor regeneration quality. While 56.25% of plant species that were only available as saplings or seedlings were regarded as “new” at the botanical garden, a total of 25% of plant species were not regenerating at all. At the study site, the species diversity as determined by the Shannon-Weiner (H’) index was 1.58. But this value shows the species diversity is included in the low biodiversity range unless they are well managed from disturbance. The species composition of the site shows a few species; only 16 plant species were found. A high number of individual species are found in the Leguminosae family.

Potential of Agroforestry Practices on Woody Species Diversity and Composition: Implication for Conservation of Indigenous Trees in Selected Districts of Tigray, Northern Ethiopia

Human activities such as expanding farmland, producing charcoal, and harvesting construction materials and fuel wood are major contributors to forest degradation and biodiversity loss in Northern Ethiopia. This study aimed to assess woody species' diversity, composition, and threat levels in different agroforestry practices to prioritize their conservation. As the result three potential Agroforestry practices were purposively identified and selected for the study. A total of 45 sample plots, 15 plots from each agroforestry practices such as Woodlot agroforestry (WLAF) (10m x 10m), Homegarden Agroforestry (HGAF) (20m x 10m), and Parkland agroforestry (PLAF) (50m x 100m). Data on woody species were analyzed using Past version 2.17c and SPSS version 20. The results identified 36, 26, and 21 woody plant species from 31, 23, and 19 genera, as well aswell as 22, 16, and 15 families in HGAF, PLAF, and WLAF, respectively. Significant differences (p < 0.001) were found among the agroforestry practices in terms of tree density, species richness, species abundance, and Shannon diversity, though species evenness did not vary. The Importance Value Index (IVI) highlighted the top species in HGAF as A. etbaica (75.2), F. albida (33.1), and A. seyal (30.6). Species with low IVI values, such as B. polystachya (1.56), R. vulgaris (1.57), G. ferruginea (1.62), and C. aurantiifolia (0.90), require significant conservation efforts. In PLAF, the key species were F. albida (131.03), A. seyal (59.33), and C. africana (26.21). In WLAF, E. globulus (61.8), A. seyal (8.83), and C. edulis (31.4) were the most abundant, frequent, and dominant. Trees and shrubs in HGAF and WLAF had smaller stem diameters compared to those in PLAF. However, WLAF had greater tree height and basal area (BA, m²) than both HGAF and PLAF, with HGAF also showing a higher BA than PLAF (p ≤ 0.05). The study concluded that HGAF and PLAF are vital for sustaining local livelihoods, providing food, and conserving biodiversity. These agroforestry systems enhance natural forests and help prevent the extinction of woody species. Therefore, developing and enhancing HGAF, and PLAF in densely populated landscapes should be integral to biodiversity conservation strategies.

Examining Woody Plant Diversity Across Indigenous Agroforestry Practices in the Kellem Wollega Zone, Western Ethiopia

Growing woody plants on farmland not only promotes biodiversity conservation but also supports the livelihood of local communities by offering essential ecosystem services. The present study aimed to assess the woody species diversity within indigenous agroforestry practices in Kellem Wollega Zone, western Ethiopia. From Kellem Wollega, three districts: Dale Sadi, Gawo Qebe,and Sadi Canqa were purposively selected. A total of 135 plots were surveyed, with 45 plots per district across various land use classes, documenting species diversity, evenness, richness, frequency, and important value index. Fifty six (56) woody species from 29 families were counted. Fabaceae family was identified as the most dominant, comprising 7 species (12.5%), followed by Moraceae and Euphorbiaceae families, each with 4 species (7.17%). About 71.43% of species identified species were categorized as trees, while 28.57% were classified as shrubs. This finding confirmed that the indigenous home garden agroforestry exhibited the greatest diversity of woody species, while woodlots exhibited the lowest diversity. Furthermore, the results indicate significant variations in species diversity across different land use categories (p<0.001). These results underscore the contribution of indigenous agroforestry practices in enhancing biodiversity and supporting a number of woody species within their ecosystem.

Tree Species Diversity and Carbon Stock of Tropical and Sub-Tropical Forests of Mizoram, Northeast India

The present study was conducted in tropical and sub-tropical forests of Mizoram, Northeast India. A total of 49 species belonging to 40 genera and 26 families were recorded in the tropical forest (TF). Whereas, in the subtropical forest (STF), 47 species belonging to 42 genera and 28 families were recorded. As per Importance Value Index (IVI), the most dominant species in TF were : Castanopsis tribuloides (47.67), Schima wallichii (40.71), Aporosa octandra (20.96) and Wendlandia budleioides (17.79). Whereas, the species such as Ilex godajam (41.42), Saprosma ternatum (32.74) and Diospyros racemosa (31.34) were the most dominant species in STF. The total tree density and basal area were 1610 individuals ha-1 and 25.016 m2 ha-1 in TF and 1380 individuals ha-1 and 24.20 m2 ha-1 respectively in STF. The diversity indices such as Shannon’s diversity index (H′), Simpson’s dominance index (CD), Margalef richness index (d), and Pielou’s evenness index (J) ranged from 2.93-3.16, 0.91-0.94, 7.82-8.15, 0.76-0.81 in both the forests. The total tree biomass was 178 Mg ha-1 in TF and 144 Mg ha-1 in STF. Similarly, the total carbon stock in TF was 85 Mg C ha-1 and 68 Mg C ha-1 in STF. Such information on these forests can serve as a valuable tool for improving our capacity to enhance biodiversity conservation efforts and management of tropical forests for their sustainable use in the future.

Assessent of tree diversity in the vegetation of ramna areas of dhaka city for better management

The present article deals with the evaluation of the existing tree species diversity in the Ramna areas of Dhaka city. Both random and stratified random quadrat sampling were used for the data collection from July 2021 to June 2022. The study identified a total of 156 tree species in 46 families. Among the sampling areas, 115 tree species were found in Ramna Park, 61 tree species in Suhrawardy Udyan, and 98 tree species in the Dhaka University area. The sampling areas overlapped significantly with many tree species. Among the species, 33% of the species were of ornamental value, followed by timber (24%), medicinal (21%), fruit (19%), and wildlife-supporting (3%). 51% of the species belonged to exotics and 49% were native. The most abundant species were Swietenia mahagoni in Ramna Park and Dhaka University and Eucalyptus camaldulensis in Suhrawardy Udyan. Based on the important value index, the most dominant species were S mahagoni in Ramna Park and Dhaka University and Ficus elastica in Suhrawardy Udyan. Among the top 15 most abundant and dominant trees, nine belonged to exotics, and the rest were native. The Shannon diversity index value ranged from 3.83 to 4.39. Ramna Park showed the highest index value (4.39), followed by Dhaka University (3.91) and Suhrawardy Udyan (3.83). Stakeholder’s consultations revealed that on average 90% of the support was found for management strategies such as native enrichment, reducing exotic dominance, planting purposeful trees, heritage plantations, and expert consultation during plantation. Identified threats included construction works, exotic presence, lack of native seedlings, and low awareness. Recommendations include promoting the dominance of native species, gradual exotic replacement, enhancing wildlife-supporting species, increasing public awareness, and integrating expert opinions into urban plantation programs. Bangladesh J. Bot. 53(3): 605-617, 2024 (September)

Influence of wildfires severity on tree composition and structure in Aberdare Afromontane Forest Ranges, Kenya

Wildfires strongly impacts on the forest ecosystems, with poorly understood consequences on the composition, diversity and structure within Afromontane forests of Eastern Africa. The impacts of wildfire on vegetation were investigated one year after the fire occurrence season. The burn severity was evaluated using Sentinel-2 satellite derived spectral index known as dNBR (difference Normalized Burn Ratio). This was used to delineate wildfire into low and high severity classes. We investigated the effects of wildfires using 36 plots of 15m radius distributed in high and low burn severities while others were laid in unburnt areas. Our findings indicated that tree height, basal area and density were significantly different along severity classes (p = 0.003, p=0.007 and p<0.000 respectively). However, diameter at breast Height was not significant along severity classes (p=0.185). The most ecologically important species based on Important Value Index (IVI) within the fire affected areas were Juniperus procera, Nuxia congesta, Olea europaea subsp. cuspidata, Protea kilimandscharicum and Scurtia myrtina. Among the five dominant tree species, the density of Protea kilimandscharicum and Olea europaea subsp. cuspidata were significant along the fire severities (p<0.05). Interaction of vegetation zones and wildfire severity indicated that only height was significant (p= 0.000) while all the other tree variables and species diversity index were insignificant; DBH (p=0.053), basal area (p=0.606), tree density (p=0.389), Shannon Weiner diversity index (p=0.843), Simpson dominance index (p=0.490) and Pielou's evenness index (p=0.248). Whereas this study was on a short-term post-fire effects on vegetation, it has shown remarkable findings which can guide restoration and management of fire affected landscapes. The study recommends evaluation of long-term regeneration and recovery to guide integrated fire management within Afromontane Forest Ecosystems.

Effects of Thinning on the Diversity, Composition, and Spatial Structure in a Mixed Temperate Forest

structure in a temperate mixed forest. Design/methodology/approach: Data were collected in a 1 ha research plot. Five scenarios were evaluated through computer simulations: no thinning (T1), thinning with removal of 25% of basal area (Gha-1), (T2), thinning with removal of 25% of Gha-1 (T3), thinning with removal of 45% of Gha-1 (T4), and thinning with removal of 70% of Gha-1 (T5). The importance value index, alpha diversity, Pretzsch's A index and structural complexity index were estimated. A spatial distribution analysis was performed using the pair-correlation function g(r). Results: Pinus douglasiana and Quercus resinosa were the species of highest ecological value. Due to the removal effect, no significant changes in tree diversity were observed in the applied thinning scenarios. However, as thinning became more intense, at least one species (Quercus candicans) was lost. Thinning from below affected the oaks and thinning from above affected the pine species, which is also reflected in the spatial distribution of the remaining trees. Limitations on study/implications: The analysis is static; therefore, it is recommended that a long-term study be conducted under varying ecological conditions. Findings/conclusions: The effect of thinning on forest diversity, composition and structure depends on the type of thinning, condition of the structure, initial composition and intensity of removal. Thinning of less than 25% of the basal area, in the immediacy, allows timber harvesting without generating changes in the diversity, structure and composition of the temperate mixed forest under study.

Composition and Potential Values of Species in the Agricultural Area of Kupang Indonesia

This research was conducted to investigate the composition and potential value of weeds species in an agricultural area of Kupang, Indonesia. Two sites (dry and wet site) were selected subjectively. In each site, three stands (100 m x 100 m) were placed subjectively and in each stand 25 plots (1 m x 1 m) were placed randomly (∑150 plots). In each plot, all weed present were recorded and their density and percentage cover calculated. Each species was grouped into broad-leaves, sedges, and grasses. To determine the potential value of the weeds, all weeds were grouped into whether they medicinal plants, animal feed or food ingredients. For each species, the number of individuals, dominance, frequency, and Importance Value Index (IVI) were calculated. Species diversity was also calculated using the Shannon-Wienner Diversity Index (H'). Overall, 46 weed species were found. The weeds with the highest IVI (&gt;5.00%) were Panicum repens L (IVI 14.80%), Bolboschoenus maritimus L. Palla (IVI 10.32%), Alternanthera sessilis L (IVI 7.47%), Cyperus rotundus L, (IVI 6.97%), Digitaria ciliaris (IVI 6.69%), Cyperus elatus L (IVI 6.63%), and Ischaemum timorense Kunth (IVI 5.02%). In general, the composition of weeds between the dry and the wet sites were relatively different. Based on the number of species and diversity index, the weed community in the wet site was relatively higher than that in the dry site. Based on the IVI, the dry site tended to be dominated by grasses and broad leaves while the wet site tended to be dominated by sedges. Based on IVI, 42.80% of all the weed species present had the potential to be used as medicinal plants, 39.81% as animal feed, and 17.39% as human food. Overall, most weed species studied had the potential to be used as medicinal plants, animal feed, and food ingredients. The potential of this weed needs to be studied more deeply in the future, including their use as an alternative source of medicine and food, especially as demand increases in the future.

Vegetation Structure, Composition and Plant Community types in Tropical Dry Deciduous Forests of Jaipur, Rajasthan, India

The research was carried out in the Aravalli Forests of Nahargarh (NWLS) and Jamwa Ramgarh Wildlife Sanctuaries (JRWLS) of Jaipur, Rajasthan, India. The vegetation structure, composition, biodiversity and plant community types were assessed across the five forest stands viz Nahargarh biological park (S1), Nahargarh Sanctuary (S2) in NWLS and Ramgarh (S3), Raisar (S4), and Digota (S5) of JRWLS, respectively. A total of 164 qaudrats of 20*20 m2 were laid to assess the vegetation data including frequency, basal area, density, importance value index (IVI), biodiversity indices (Shannon-weiner, Simpson, Pielou and Margalef’s) and plant community types. The tree basal area ranged between 18.56 -34.36 m2/ha while stand density was 923-1433 tree/ha. Our study indicated the dominance of family Fabaceae with 20 species and 11 genera with Anogeissus pendula showing the maximum frequency, density, mean basal area and IVI. Further, the agglomerative hierarchal clustering showed five types of plant communities with Anogeissus-Adhatoda as the most widely spread community in these forests. Among the two sanctuaries, species diversity was higher for JRWLS (2.83) than NWLS (2.80). The current study provides important baseline data for forthcoming research on monitoring and preserving these forest’s biological diversity. The significance of present study will provide insight into the structure and variety of tree species in tropical dry deciduous forests.

Phytosociological Study of Weed Communities in Zea Mays Cultivation: Contributions to Sustainable Development Goals (SDG'S) in the Ecuadorian Tropics

Objective: This study investigates the phytosociological characteristics of weed communities associated with Zea mays cultivation in different zones of the Ecuadorian tropics, aiming to identify and classify weeds to develop effective management strategies that enhance productivity while minimizing environmental impacts Theoretical Framework: The research is based on the concept that weeds, or 'noxious weeds,' significantly challenge maize cultivation by competing for essential resources. Theories related to plant competition and agroecosystem sustainability underpin the study Method: The methodology involves a phytosociological survey across five farms in Mocache, Ventanas, and Balzar. Using 45 quadrats of 50 x 50 cm in a zigzag pattern across one-hectare plots, weed species were identified and quantified. Data were analyzed to calculate biodiversity and importance value indices. Results and Discussion: Mocache had the highest weed population, while Balzar exhibited greater species diversity. Similarity indices, including Jaccard and Bray-Curtis, revealed distinct patterns in species distribution and dominance. These findings are discussed in the context of sustainable agriculture, highlighting the implications for weed management and acknowledging potential limitations due to environmental variability. Research Implications: The study provides insights into sustainable weed management in maize agroecosystems, contributing to strategies aligned with SDG 2 (Zero Hunger) and SDG 15 (Life on Land), promoting practices that enhance food security and biodiversity conservation. Originality/Value: This research offers a novel phytosociological analysis of weed communities in tropical maize cultivation, contributing to sustainable agriculture and aligning with global sustainability goals.

Stands diversity and population structure of five ethnoveterinary woody species according to climatic zone and human disturbance in Benin (West Africa)

Farmers continue to use medicinal plants, alone or in combination with veterinary medicines, to treat animal diseases, especially in developing countries. The study aimed to determine the effect of climatic zone and anthropic disturbance level on the diversity of the natural stand and structures of Morinda lucida Benth, Spondias mombin L., Terminalia leiocarpa (DC.) Baill, Crossopteryx febrifuga (Afzel. ex G. Don) Benth, and Vitex doniana Sweet, five plant species often used in ethnoveterinary medicine in Benin. A floristic inventory was conducted in 206 plots of 0.15 ha each, distributed across 6 forests/hunting areas as well as surrounding fields and fallow land. The data were analyzed using R software by calculating the importance value index and the population structural parameters (density, basal area, mean height, etc.). The results showed that the floristic composition of the habitats of the five target species varied by climatic zone and disturbance level. Morinda lucida, S. mombin, and V. doniana were available in stands undergoing heavy disturbance in the Guinean zone, whereas T. leiocarpa and C. febrifuga were more available in the Sudano-Guinean and Sudanian zones. Values of structural parameters of these species were higher in the Guinean zone than in the other two zones. Furthermore, the results of the diameter structure showed C-values ranging from 1 to 3.6, suggesting the predominance of young individuals. This suggests strong human pressure on the adults of studied plants. These results should be used to contribute to the sustainable use of these species. Recommendations are made for the sustainable use of these five species, especially T. leiocarpa and C. febrifuga, which were heavily exploited given their low availability in stands under high human disturbance.

Pervasive impacts of railway edge effects on edaphic parameters and vegetation distribution patterns

Addressing the ecological impacts of transport corridors while planning any transport network is paramount for a better of understanding ecological processes, biodiversity distribution, and ecosystem resilience. Here, we evaluated the impacts of railway edges on edaphic parameters, plant diversity, and composition in the northwestern Himalaya as a function of perpendicular distance from the railway track. In 2014 and 2017, we sampled vegetation plots across 31 sites distributed along 119 km of the Kashmir railway to test the effect of railway tracks on edaphic and vegetative parameters in short-term periods. T-shaped plots were laid comprising four sub-plots, one parallel to the track and the other three perpendiculars to it. We adopted the Mountain Invasion Research Network road survey methodology for data collection. We found (i) an increasing trend in all soil parameters (electrical conductivity, salinity, organic carbon, available nitrogen, and available phosphorus), except pH, as the distance from the railway track increased; (ii) significant railway edge effects on the importance value index of plant growth forms, life span, nativity and taxonomic group across space (distance of plots from the track) and time (2014–2017); and (iii) a significant spatiotemporal railway edge effects on plant species composition. Our results are pioneering in showing that railway tracks crossing through different ecosystems alter the edaphic conditions, resulting in direct and indirect edge effects on key abiotic and biotic factors, which in turn impact the vegetation of the surrounding natural habitats on both sides of the railway track. Our study contributes toward a better understanding of the role of anthropogenic edges like railways on edaphic parameters and vegetation distribution.

Assessment of mangrove structures and biomass on islands along the Java Sea: a case study on Bawean Islands and Karimunjawa Islands

Mangroves on the islands along the Java Sea play a crucial role in supporting biodiversity, protecting coastlines, and sequestering carbon. However, there is a lack of information on mangrove structure and biomass in the area. This study aimed to assess the mangrove structures and biomass on Desa Daun, located on the Bawean Islands, and Kemujan Island, located on the Karimunjawa Islands, respectively. The study utilized a combination of line transect and quadrant plot methods with a size plot of 10x10 m. We established 7 line transects and 28 quadrant plots in the mangrove forest of Desa Daun and similarly set up 7 line transects and 21 quadrant plots on Kemujan Island. Within each quadrant, the mangrove species were identified, and their diameters at breast height (DBH) were recorded. To assess the relative significance of each species, the importance value index (IVI) was calculated, and allometric equations were applied to estimate biomass and carbon storage in the trees. PlanetScope imagery was also used to quantify the carbon stock of mangroves on those islands. In Desa Daun, 13 mangrove species were identified, while 12 species were recorded on Kemujan Island. The species Nypa fruticans and Excoecaria agallocha exhibited the highest IVI in Desa Daun and Kemujan Island, respectively. Notably, Rhizophora apiculata demonstrated the greatest biomass in both locations, with measurements of 43.08 Mg B/ha in Desa Daun and 102.22 Mg B/ha in Kemujan Island. Overall, mangrove stands on Desa Daun stored biomass of 113.60 Mg B/ha and carbon of 50.98 Mg C/ha, whereas mangrove stands on Kemujan Island stored biomass of 295.04 Mg B/ha and carbon of 131.95 Mg C/ha. Mangrove stands of the whole Bawean Islands sequestered 22,941 Mg C, while Karimunjawa Islands hold much higher C stocks, 79,451 Mg C. Despite being smaller in size, the Karimunjawa Islands have more extensive mangrove coverage compared to the Bawean Islands due to their geomorphological characteristics, which in turn influence their mangrove structures and carbon stocks. However, the loss of mangroves in the Karimunjawa Islands due to aquaculture expansions could increase carbon loss in the islands.

ANALYZING THE IMPACT OF CONSTRUCTION DELAYS ON DISPUTES IN INDIA: A STATISTICAL AND MACHINE LEARNING APPROACH

In Major construction projects execution and performance were being negatively impacted by claims and disputes in terms of cost overrun, quality, stakeholders relationships, and productivity. Therefore understanding the significance of underlying the claims is essential. In this study, the primary root causes behind delay claims and disputes in construction projects were identified, examined, and rated. The significance of these factors was assessed using Relative Importance Index (RII) values. In addition, a machine learning model employing the Random Forest Genetic Algorithm (RFGA) was implemented to foresee the related risks and ascertain their levels. In a pilot survey, the data were collected across multiple construction projects at different phases such as scrutiny stage, design and planning stage, bidding stage, operation stage, and maintenance or after-construction stage. From Relative Important Index values from the statistical approach, it emerges that delay claims are generally causes from the owner followed by project-specific activities. Delays in processing bill payments, natural disasters, lack of contract awareness, and delay in final bill payment are the top causes of delay claims which converted to conflicts and disputes in mostly operating stage. The Random Forest Genetic Algorithm model predicted that factors like altering the original design, reluctance to cooperate by contractor, and increase of wages have lower risk whereas factors Poor site conditions, delay in approvals of schedules and change orders, natural calamities, late in running bill payment, repetition of work due to error in original work are at higher risk in terms of conflict and dispute. The model gives an accuracy of 0.89 and 0.87 for training data and testing data. The study will highlight possible research avenues and enhance project management strategies so that the project succeeds its goal.

Climate change ecological vulnerability and hotspot analysis of himalayan forests in North-Eastern region, India

The Himalayan forests are vulnerable to climate change leading to disturb the current flow of critical ecosystem services to the dependent population. Present study attempts to evaluate the current vulnerability status of major forest types in Nagaland, India due to climate change along with identifying the hot spots for mitigating the vulnerability of the forests. Vulnerability of mixed moist deciduous, pine, wet hill and wet temperate forests were evaluated using the IPCC framework. Local Moran's I analysis, hot spot analysis and a histogram analysis of the vulnerability were made in QGIS. Field data such as Shannon-Wiener Index and Importance Value Index along with secondary data such as edaphic factors, vegetation factors and climatic variables were used for vulnerability analysis. Analysis results that mixed moist deciduous forests had the highest area in under high-high clusters, hot spots and was highly vulnerable. The result suggests that very dense or moderately dense forest cover were less vulnerable than low density forests in the region. The study provides baseline information along with identification of vulnerable hot spot forests for future climate change policy and management of resources at the division level. The study suggests strengthening the less dense forests along with increasing the biodiversity through suitable strategy for mitigating the vulnerability.