Girth At Breast Height Research Articles

Geoinformatics and Modeling Approaches for Estimating Above-Ground Biomass in the Moist Deciduous Forests of Uttara Kannada, Karnataka, India

The present study aims to estimate Above-Ground Biomass (AGB) in the moist deciduous forests of Mundgod Taluk, Uttara Kannada district, Karnataka, India using a combination of field sampling and remote sensing techniques. AGB was assessed using Sentinel-2A satellite imagery with a spatial resolution of 10 meters. Field data were collected using the Point-Centered Quarter (PCQ) method, it includes measuring tree girth at breast height (GBH), tree height, and canopy density. AGB was calculated using artificial form factor and specific gravity of tree species and further modelled using the Normalized Difference Vegetation Index (NDVI) derived from satellite data. The results showed a significant correlation between canopy density and biomass, with very dense forests exhibiting the highest AGB values. The field-measured AGB was 436.96 t/ha for very dense forests, 259.89 t/ha for moderately dense forests, and 161.67 t/ha for open forests. A linear regression model developed between AGB and NDVI showed a high R² value of 0.91 for open forests, 0.87 for moderately dense forests, and 0.85 for very dense forests. The total area-weighted biomass for the study area was estimated at 8.87 million tons, with 4.79 million tons in very dense forests, 3.44 million tons in moderately dense forests, and 0.76 million tons in open forests. The regression model validation indicated low Root Mean Square Error (RMSE) values, with the moderately dense forests 8.81 t/ha and the in very dense forests 7.54 t/ha. This study highlights the effectiveness of integrating field measurements with remote sensing for rapid, reliable AGB estimation. The approach offers valuable insights into biomass distribution and carbon sequestration potential, providing a scalable method for carbon inventories at state and national levels, contributing to forest management and climate change mitigation efforts.

Patterns of forest community diversity, regeneration potential and carbon storages along an altitudinal gradient in Eastern Himalaya, India

This study showed changing patterns in the plant species composition, diversity, and carbon storage potential of different forests along altitudinal gradients (i.e. 100 – 1900 m) in Eastern Himalayan India. Different tree, shrub and herb species were sampled along the altitudinal gradients ranging from tropical to temperate forests through Nested Plot design. In each forest, vegetation sampling was made by establishing a permanent plot of 250 m × 250 m as per ISRO-GBP/NCP-VCP protocol. Individuals of trees ≥10 cm girth at breast height (GBH), shrubs and herbs were recorded in 4, 8 and 16 subplots of 31.62 m × 31.62 m, 5 m × 5 m and 1 m × 1 m, respectively. Community attributes such as species richness, density, basal area, diversity indices and biomass and carbon storages were computed for each study site. A total of 5 forest communities (2 each from tropical and subtropical and one from temperate forest) were identified. The woody species diversity was highest in the subtropical forest followed by tropical and temperate forest. Altitude played an important role in the Eastern Himalayan Mountains in the establishment and distribution of forest community. Forest community composition changes with elevation, for instance, the dominant communities like Dipterocarpus retusus–Phoebe goalparensis–Schima wallichii (D-P-S), Gmelina arborea–Schima wallichii-Duabanga grandiflora (G-S-D), Schima wallichii–Duabanga grandiflora–Alstonia scholaris (S-D-A), Alstonia scholaris–Terminalia myriocarpa–Bischofia javanica (A-T-B) and Acer thomsonii–Rhodendron arboreum–Quercus lamellose (A-R-Q) were present at elevational ranges of 100–300 m, 300–700 m, 700–1100 m, 1100–1500 m and 1500–1900 m, respectively. The study showed that about 41–57% of the tree species exhibited good regeneration followed by 23–30% as fair, 6–16% as poor, and 6–21% species did not show regeneration along the altitudinal gradient. The total biomass carbon (Mg C ha−1) varied from 84.74 to 163.56 in tropical, 103.12 – 156.41 in subtropical and 133.05 in temperate forest. In conclusion, community composition, regeneration pattern and biomass carbon storage changes along altitude because of altered biophysical characteristics. However, despite variations in elevation, factors for forest disturbance at different altitudes significantly contributed to the community attributes and overall accumulation of biomass carbon. Hence, the traditional management practices carried out by local communities also play a crucial role in shaping the structure, composition, and carbon dynamics of forest ecosystems. Understanding the impacts of these practices is essential for promoting sustainable forest management by conserving forests and preserving carbon stocks for mitigating climate change in future. This study emphasizes the importance of long-term forest monitoring to promote biodiversity conservation and formulate conservation strategies that support sustainable forest management policies to which ensure continuous provision of ecosystem services in the region.

Assessment of morphological variability in natural populations of Haldina cordifolia (Haldu)

The surveys were conducted in natural populations of Haldina cordifolia in the forest areas of three states of central India namely Madhya Pradesh, Chhattisgarh and Maharashtra. Based on the growth parameters of the individual tree, a total of thirty trees from nine forest divisions of these three states were selected as candidate plus trees (CPTs). Variation was observed in girth at breast height (GBH), total height, and clear bole height (CBH) of trees surveyed. The maximum GBH was recorded in the CPTs of Balrampur (243.75 cm) while the minimum was recorded in Balaghat (115 cm). The maximum height of CPTs was recorded in Dindori (30.25 m) while the minimum was recorded in Allapalli (19 m). The maximum CBH% of total height was recorded in Bilaspur (44.22) while the minimum was recorded in Katghora (37.31). Higher GBH and height of trees may be resulted due to more age of trees. CPTs of Bilaspur were of middle age and showed the highest CBH% (44.22) and relatively low GBH and height when compared with those of Dindori and Balrampur. With age, the trees of Bilaspur will gain more height and girth which will result in higher yield.

Effect of Morphological Characteristics of Fruit Orchards on Soil Physio-chemical Properties

Biophysical characteristics of 16-year-old fruit orchards and their influence on soil physico-chemical properties of sixteen-year-old fruit orchards established at Krishi Vigyan Kendra, Birouli, Samastipur (Bihar) were compared. Fruit orchards were Mango (Mangifera indica) var. Malda, Litchi (litchi chinensis) var. China and Aonla (Emblica officinalis) var. NA-7. An investigation was undertaken to evaluate the dynamics of Oxidisable Organic Carbon (Coc), SOC sequestration, Bulk Density (BD), pH and Electrical Conductivity (EC) in fruit orchards. All the orchards significantly improved SOC showing 12.9 to 44.6 % higher than that in open (without trees) and followed the order: Aonla > Litchi > Mango. The total SOC increased by 10 to 20 % at the surface and 15 to 35 % in the lower depths. The crown diameter of Mango, Litchi and Aonla orchards were 11.64 m, 8.61 m and 8.6 m and girth at breast height (GBH) varied from 9.53 m in Aonla orchard to 5.6 m in Litchi orchard. By and large, Aonla orchard may be considered as the best orchard production system from the standpoint of SOC build up and improvement in soil physic-chemical properties. Hence, its promotion and expansion as land-use practices in the calcareous belt of Bihar will be helpful for food security and mitigating climate change.

ESTIMASI SIMPANAN KARBON PADA BIOMASSA MANGROVE DI TAHURA NGURAH RAI

Mangroves contribute to mitigating climate change by storing carbon. As mangrove forests have a high rate of carbon sequestration and storage, carbon stock calculations are required to quantify the accumulation of carbon stored in a site to determine its involvement in decreasing greenhouse gas emissions. This study aims to estimate carbon storage at the Mangrove Information Center (MIC) by using an allometric calculation of the mangrove above-ground biomass data. Data collection was carried out on January 10-14, 2022 at the MIC, with an area of 322 ha. The method used is a 1000 meters line transect plot divided into 15 measuring plots in three mangrove ecological zones (front, middle, and back). Biomass data were taken in a non-destructive way based on measurements of the circumference girth at breast height (GBH) and the results were calculated using allometric. According to data analysis, the average total surface biomass of mangroves in MIC is 781.30 kg, with estimated carbon storage in MIC is 36,727 tons/ha. Overall, the total carbon stock in the stratum MIC is 11.826,253 tons. The highest estimated carbon storage is in Plot 9, which is 91,799 tons/ha, while the lowest estimated carbon storage is in Plot 2, which is 13,873 tons/ha. The high numbers of carbon storage from mangrove above-ground biomass are mostly found in the middle and front zones because of the very dense mangrove density.
 Keywords: mangrove; above-ground carbon estimation; climate change mitigation

Growth Assessment of Young Plantation of <i>Santalum album</i> with <i>Dalbergia latifolia</i> as Host

Indian Sandalwood ( Santalum album ) is a highly valued partial root parasite tree and the prized heartwood is considered as 'wood of choice' in carving and oil obtained from steam distillation of heartwood is regarded as 'aroma of choice' in perfume industry. Due to large scale reduction in natural population, it is categorised as 'threatened' by International Union for Conservation of Nature. Earlier it was recognised as Royal tree in Karnataka and Tamil Nadu, because of which even basic information about growth was lacking. With the relaxed government policies and the increased demand for heartwood and oil, farmers and entrepreneurs are motivated to cultivate Sandalwood. Presently, numerous plantations are being raised and documenting growth data from these plantations is very important. During a survey of Sandalwood plantations in Karnataka, an eight year old unique Sandalwood plantation was identified which had Indian Rosewood ( Dalbergia latifolia ) as host and growth data was collected. The Sandalwood trees girth at breast height (GBH) varied from 13.9 to 31.2 cm with an average GBH of 19.24 cm and average tree height was 6.02 m varying from 5.0 to 9.5 m. Rosewood had mean tree height and GBH of 8.72 m and 29.18 cm, respectively. Core samples collected from Sandalwood trees above 30 cm girth did not show any indications of heartwood formation. This study would augment necessary information required for developing package and practices on Sandalwood cultivation.

A dataset for vascular plant diversity monitoring for the natural World Heritage site on Amami‐Oshima Island, Tokunoshima Island, and the northern Okinawa Island

AbstractThis data paper presents the vascular plant biodiversity sampled from four plots on Amami‐Oshima Island, three plots on Tokunoshima Island, and one plot on Okinawa Island within the natural World Heritage site, and an additional three plots in southern Kyushu using the standardized belt‐transect survey method during July 2012 to October 2020. The dataset includes 99 families, 215 genera, and 381 species of vascular plants, and provides species occurrence among 10 subplots for all vascular plants, girth at breast height (GBH) and height of all trees and climbers with GBH ≥ 3.2 cm or height ≥ 4 m in each 5 × 100 m plot. This dataset serves as baseline data for subsequent plant diversity monitoring of the natural World Heritage site. The Darwin Core Archive is deposited in the Global Biodiversity Information Facility (GBIF) through the Japan Initiative for Biodiversity Information, and are thus accessible through the GBIF portal under the Creative Commons Attribution 4.0 International license. The detailed Metadata for this abstract published in the Data Article section of the journal is available in MetaCat in JaLTER at http://db.cger.nies.go.jp/JaLTER/metacat/metacat/ERDP‐2022‐03.1/jalter‐en.

Ultrahigh-density genetic map construction and identification of quantitative trait loci for growth in rubber tree (Hevea brasiliensis)

Ultrahigh-density genetic mapping is used extensively for gene discovery, mapping quantitative trait loci (QTL), and assisting in crop breeding. However, genetic mapping of rubber trees (Hevea brasiliensis) has hitherto been limited in terms of both types and resolution. In this study, 214 F1 progenies derived from a cross of IAN 873 × REYAN 106 were genotyped via a whole-genome resequencing-based (WGRS) approach. From the 44,438,656 single nucleotide polymorphisms (SNPs) obtained from the genotyping, an ultrahigh-density genetic map was constructed using 203,124 SNPs, which included 2099.12 cM across eighteen linkage groups of the entire rubber tree genome. To the best of our knowledge, an ultrahigh-density genetic map of a rubber tree constructed via the WGRS approach has not yet been reported in literature. Two phenotypes associated with growth, namely, the girth at breast height (GBH) and tree height (TH), were investigated under a six-month interval. A total of six QTLs were found, in which qGBH11 and qGBH18 were detected repeatedly. Based on the physical positions of the bin markers that flank the QTLs, 47 genes identified within the qGBH11 locus, as well as the gene HB11G00752, were selected as the candidate genes that encodes ent-kaur-16-ene synthase (KS), regulating gibberellin biosynthesis. The search results for the KS gene family in the genome indicated that six out of ten KS family members were located in the qGBH11 allele. Expression analysis further shed light on the differential expressions of the KS family genes between F1 individuals having fast and slow growth. These results are expected to provide new insight into the genomic regions that control growth in rubber trees, and also facilitate the development of more effective approaches for breeding fast-growing timber latex clones.

Carbon stock and carbon credit of Tectona grandis plantation in Konkan region of Maharashtra

A survey-based study on carbon stock, carbon assimilation and carbon credit of teak plantation was conducted on existing teak plantation of Dr Balasaheb Sawant Konkan Agriculture University, Dapoli, dist Ratnagiri, Maharashtra during 2020-21. The growth data of 318 teak trees from experimental plot were collected and carbon in trees was quantified by non-destructive method using allometric equation. The average girth at breast height (GBH) of trees was recorded 21.03 cm and height 10.13 m under the plantation. Carbon stock of 6 years-old age plantation was found 15.60 tonnes/ha and CO2 assimilation or offset by biomass 57.25 tonnes/ha. It was concluded that the carbon sequestration potential of teak and its growth within 6 years was optimum at Konkan coastal zone.

Developing an Empirical Formula for Volume of Timber Availability from Different Species of Trees in Gujarat

The standing tree volume is a measurement of the amount of merchantable volume and available growing stock in forests and trees outside forest areas. The precise estimation of the tree log volume plays an important role in sustainable forest management and also in trees outside forest areas. Several scientists have derived various tree log volume calculation formulae, which are used in estimating standing tree volume. The Gujarat State has very rich forest biodiversity. The forest department has done very good work in conserving existing forests and achieved outstanding success in planting and raising trees outside forest areas through a successful social forestry program in the State. The efforts through public participation have resulted in to increase in forest cover of the State. The present investigation was carried out at Gujarat Forest Research & Training Institute, Gandhinagar campus to develop an empirical formula for estimating standing timber availability from different selective tree species of Gujarat. The attempt has been made to measure Girth at Breast Height (GBH), Clean Bole Height (CBH) of selected tree species, and round log volume was calculated using a quarter girth formula assuming it to be a cylinder. Considering principle factors behind tree growth that 1) the height is a function of girth, 2) young aged tree grows at a double rate that in middle age and 3) mature tree hardly puts any height or girth, a general growth formula has been derived. The general growth formula was validated for different species based on actual measurement of effective height. Finally, the empirical formulas were developed based on the Regression of derived formula V = A G 2 10 -5 e bG for different tree species.

Population status of Heritiera fomes Buch.-Ham., a threatened species from Mahanadi Mangrove Wetland, India

Heritiera fomes Buch.-Ham. is assessed as an endangered mangrove species by IUCN, and information on population status is lacking. The present study assesses the status of H. fomes in Mahanadi Mangrove Wetland on the east coast of India. Three forest blocks were selected and sampled for this study. Among these, the mean girth at breast height (GBH) of H. fomes was the highest in Hetamundia (HD) forest block. GBH of H. fomes was inversely proportional to the cumulative disturbance index (R2= 0.7244, p value <0.005). The relative density was maximum for H. fomes (56%) at Bhitarkharnasi (BK), and for Excoecaria agallocha at Hetamundia (HD; 35%) & Kansaridia (KD; 54%), respectively. Excoecaria agallocha is a dominant species possibly impacting natural populations of H. fomes. Climate change and rising sea levels may also negatively affect the existence of this species. Therefore, appropriate strategies should be taken for conservation of this globally threatened mangrove species prior to its extinction.

Variation in structural diversity and regeneration potential of tree species in different tropical forest types of Similipal Biosphere Reserve, Eastern India

Understanding the regeneration potential of tree species in natural forest ecosystems is crucial to deliver suitable management practices for conservation of biodiversity. We studied the variation in structural diversity and regeneration potential of tree species in three different tropical forest types, namely: Dry Deciduous forest (DDF), Moist Deciduous forest (MDF) and Semi-evergreen forest (SEF) of Similipal Biosphere Reserve (SBR), Eastern India. Random sample plots were laid for studying the diversity and distribution pattern of tree, sapling, and seedling stages of the tree species. A total of 84 species belong to 73 genera and 35 families were recorded from the study area. The highest species richness was reported for tree (54 species) in DDF, sapling (24 species) in MDF and seedling (22 species each) in SEF and DDF. The overall density of trees with GBH (Girth at Breast Height) ≥ 10 cm was 881 individuals/ha. The regeneration potential of tree species was poor in DDF (39%) where as it was fair in SEF (43%) and MDF (49%). Most of the dominant tree species at each forest type performed good regeneration. The species such as Ehretia laevis Roxb., Bridelia retusa (L.)A.Juss., Mitragyna parviflora (Roxb.) Korth., Terminalia tomentosa Wight & Arn., Terminalia chebula Retz., Terminalia bellirica (Gaertn.) Roxb.etc. had either no regeneration or poor regeneration potential need immediate attention for conservation measures. The diversity of standing trees did not correlate with seedling or sapling diversity in all the cases but there was significant correlation among seedling and sapling diversity found in DDF (r = 0.67, p ≤ 0.05) and SEF (r = 0.83, p ≤ 0.05). Further, the diversity of tree species increased with their age (trees > saplings > seedlings) and the stem density decreased with their age (trees < saplings < seedlings) in all three forest types. The results of our study would be helpful in understanding the structural attributes, diversity and regeneration potential of different tropical forest types of India for their better conservation and management.

Genetic parameters in a clonal test of Tectona grandis in Mato Grosso, Brazil

Teak (Tectona grandis) is a high-value timber species in tropical regions. In Brazil, although teak has a high productivity, there are few studies related to its genetic improvement. This work aimed to estimate genetic parameters and evaluate potential gains of selection in a clonal test of teak installed in the state of Mato Grosso, Brazil. The experimente is in a randomized block design, with five replications, 3x3 m spacing, 22 treatments, and plots with six individuals. At five years, the genotypes were evaluated for survival (S), tree total height (H) and girth at breast height (GBH). There was significance and feasibility of selection for S and GBH. For H, the result was not significant, indicating few gains with the selection. The genetic parameters of clonal mean heritabilities and accuracy were of moderate magnitude for S and GBH and low for H. To best of our knowledge, this is the first work that estimates genetic parameters in a clonal teak test in the field in Brazil.

Carbon Sequestration Potential of Urban Green Spaces (PMC Gardens) in Pune City, India

Aim: To estimate the Carbon sequestration potential of trees in Urban green spaces of Pune city.&#x0D; Study Design: The methods suggested by Ravindranath and Ostwald were used for measuring the above and belowground biomass and estimation of carbon pool. Random sampling technique was used to collect soil samples. As the study area were one acre and above, each and every tree was sampled for various parameters. The GPS instrument was used for measuring latitude and longitude of each and every tree.&#x0D; Place and Duration of Study: The gardens developed by Pune Municipal Corporation (total 66 having an area one acre and above) Pune, Three years( from January 2015 to December 2015, January 2016 to December 2016, January 2017 to December 2017)&#x0D; Methodology: The gardens having an area one acre and above were selected for the work. Each and every tree is sampled along with its position on ground by using GPS instrument. Sampling of tree includes measuring Height and Girth at breast height (GBH). Later, the parameters like Volume, Mass, Wood density, Above and Below ground biomass, Total biomass and Total carbon were calculated as per the standard methods given by Ravindranath and Ostwald [1] Soil samples were collected randomly from a depth of 30 cm as it is a zone of highest microbial activity. Walkley‐Black Wet Oxidation method was used to find out soil organic carbon.&#x0D; Results: Total amount of above and belowground carbon sequestered was estimated to be 7,00,507.83 tonnes; litter and deadwood 24,904.05, and soil organic carbon 1879.905; and the sum of all were 7,27,291.785 tonnes. The exotic species sequester 2,69,287.4 tonnes and native sequester 80,966.55 tonnes of carbon. The rates of carbon in active markets are US$ 30 (Thirty dollars) per tonne. &#x0D; Conclusion: Putting a conservative value of US$ 30 per tonne of CO2 locked in these sampled gardens, this carbon sink of about 7,27,291.785 tonnes of CO2 is worth of US $ 21818753.55 or Indian Rs. 1606733011.422/-It will help in Climate mitigation and reducing the carbon footprints of Pune city.

The Abundance and Distribution of Mangrove Gastropods from Kuala Selangor Nature Park, Selangor

This study reports on the abundance and distribution of mangrove gastropods from Kuala Selangor Nature Park, Malaysia (KSNP). The line transect method with quadrats (5m x 5m) was employed to sample the gastropods. Gastropods were collected from the leaves, branches, stems and roots of trees and the mangrove floor. Nineteen gastropod taxa from seven families were recorded from the Bruguiera, mixed (Bruguiera, Avicennia and Rhizophora), Avicennia and Rhizophora zones. Avicennia sp. recorded the largest Girth at Breast Height (GBH) (mean±sd=37.3±18.2 cm) while Bruguiera sp. recorded the smallest GBH (mean=22.36±8 cm). The overall density of the gastropods at KSNP was 0.85 no/m2. The gastropod density was higher at the Avicennia &amp; Rhizophora zone (150-200m (closer to the mudflats) (0.064±0.084 no/m2) followed by the mixed zone (50-150m) (0.046±0.30 no/m2) and lowest at the Bruguiera zone (0-50m) (0.08±0.080 no/m2) (closer to the coastal bund). Gastropod density between sampling zones did not vary significantly (p&gt;0.05) but generally increased from the bund towards the mudflat edge. Further studies of the role of gastropods in the coastal food chain, as bio-indicators of habitat change and as potential food source for local populace are needed.

Short-term girth increment and biomass changes in tree species of Javadhu hills, Eastern Ghats, Tamil Nadu, India

Patterns of tree growth, biomass changes in 10 ha permanent plots of tropical moist evergreen forest in Javadhu hills of the Eastern Ghats, India, were investigated between 2015 and 2017. All trees ≥30 cm girth at breast height (GBH) were measured, tagged and the point of measurement (POM) was paint-marked. Short-term girth increment and biomass of tree species was studied after two years in October 2017, by re-measuring all the tagged trees exactly at the same POM. There was no change in species richness during the study period. Overall, at the tree community-level, the mean annual girth increment of was 0.93±0.10 cm yr−1. The mean stand basal area increased by 0.019 m2 ha−1 i.e. from 208.76 m2 ha−1 in 2015 to 209.98 m2 ha−1 in 2017. The above ground biomass increased totaled 96.3 Mg in 10 ha study plots (an average 9.63 ha−1). Simple linear regression between leaf surface area of trees and mean annual girth increment produced not any strong correlation (R2 = 0.1414).

Genetic variation in carbon isotope discrimination-based water use efficiency of teak (Tectona grandis L. f.) and its association with growth and wood quality traits

Teak (Tectona grandis L. f.) is one of the most preferred tropical timber species for afforestation, reforestation, and commercial plantation in the world. In the event of global warming caused by projected climate change, water-use-efficient teak planting stock would become essential for breeding and plantation activities. To characterize and to evaluate the association of water-use efficiency (WUE) with other growth and wood quality traits, we measured height, girth at breast height (GBH), wood density (WD), and carbon isotope discrimination (CID) values of 162 teak plus trees in a national teak germplasm bank (NTGB). The genetic diversity and structure of these accessions were also confirmed through 21 microsatellite markers for confirmation of their representation of teak meta-population in India. Results indicate 30.43% variation in average height (11.17 ± 3.40 m), 25.51% variation in GBH (67.18 ± 17.14 cm), and 7.48% variation in WD (789.24 ± 59.04 kg/m3) among the accessions. The accessions exhibited a significantly high level of genetic polymorphism (88.74%) with a moderate level of Shannon’s diversity index (0.53) and comparatively low heterozygosity (0.27). No significant correlation was found between height and GBH with the CID values. This confirms that the measurement of growth and wood quality traits in teak alone is not helpful to tree breeders for indirect selection of water-use efficient trees. Rather, assessment of more specific traits related to growth, wood quality, and WUE of teak in different locales will be required to improve the teak germplasm in India.

Mathematical model of DBH uncertainty from the shape of the wood cross-section

We investigate the uncertainty of Diameter at Breast Height, or DBH, of woods via a simple mathematical model. Usually, the DBH is not measured directly. The measurement is done on the Girth at Breast Height (GBH), which, by definition, is the circumference of wood at 130 cm above the ground. The DBH can then be calculated, assuming that the wood cross-section is a circle. This can introduce uncertainty to the DBH due to the irregularity of the shape of the wood cross-section. In this work, we approximate the wood cross-section by an ellipse, which can be fitted to the cross-section better than the circle. However, the eccentricity of the fitted ellipse is unknown, so we treat it as a random variable. The discrepancy between the diameter of the circle with the same area as the fitted ellipse, and the diameter of the circle with the same circumference as the GBH, is calculated. Monte Carlo simulations are performed to obtain the uncertainty of the DBH.

Species diversity, population structure, and regeneration status of trees in Fakim Wildlife Sanctuary, Nagaland, Northeast India

Abstract. Ao A, Changkija S, Tripathi SK. 2020. Species diversity, population structure, and regeneration status of trees in Fakim Wildlife Sanctuary, Nagaland, Northeast India. Biodiversitas 21: 2777-2785. The plant species composition and diversity represent the overall health of the forest ecosystems and provide useful insight on forest conservation, and the species regeneration is important in assessing the potential of the forests to serve the society on sustained basis. This present study aimed to assess the species diversity, population structure, and regeneration status of the trees in temperate forest of Fakim Wildlife Sanctuary, Nagaland, Northeast India. Tree species composition, population structure and regeneration status were analyzed by randomly establishing eight plots of 0.1 ha within the sanctuary. Density, basal area, abundance, evenness, and other diversity indices were calculated for mature trees with girth at breast height (GBH) ≥ 30 cm. A total of 60 tree species belonging to 40 genera and 27 families were recorded. The most dominant families recorded were Lauraceae and Rosaceae. The total tree density recorded from the forest was 432.5 individuals ha-1 with a basal area 42.8 m2 ha-1. Cinnamomum zeylanicum and Lithocarpus pachyphyllus had the highest density with 17.58 individuals ha-1 and Lithocarpus pachyphyllus had the highest basal area with 2.64 m2 ha-1. The species with the highest IVI was Betula alnoides (17.13). Girth class of 30-60 cm had the highest density and basal area with 280 individuals ha-1 and 20.7 m2 ha-1. The diversity indices such as Shannon-Wiener index, Simpson index, Pielou evenness index, and Margalef species richness index were 3.90, 0.93, 0.92, and 11.59, respectively in the wildlife sanctuary. The present study showed that 41% of tree species exhibited good regeneration status, 31% as fair regeneration, 8% as poor regeneration and 20% had no regeneration. The present data will be useful to understand the current status of tree species and will serve as baseline information to the forest department, policymakers and conservationists to develop management plans for the conservation of priority species in the area.

Tree species composition and diversity in abandoned Jhum lands of Mizoram, North East India

Shifting agriculture system (locally known as Jhum) is the main driver of deforestation and forest degradation in north eastern region. This system has been extensively practiced to sustain the livelihood in rural areas of Mizoram which possesses serious threats to forest ecosystem and soil fertility. The course of vegetation development in secondary forest in abandoned fallow is a major concern to understand the process of succession in different fallow length. This study was undertaken in Aizawl and Mamit districts, Mizoram with the objectives to determine the tree species diversity, richness and abundance in different fallow periods. Fallow ages of 2–5 years (F5), 6–10 years (F10), 11–20 years (F20) and 21–30 years (F30) were selected with a total number of 37 sites and two circular plots of 12.6 m were laid in each site to carry out extensive enumeration and analysis of tree species. A total number of 91 tree species and 38 families were recorded. The number of trees increased by 47% from F5 to F10 but the same was decreased by 35% from F10 to F30. Ecological indices indicate high diversity and species richness in F10 and F30 compared to F5 and F20. The basal area significantly increased with the length of fallow period. The average girth at breast height (GBH) in F5 was 30 cm but in F30, the GBH increased to 130 cm. The dominant species changed as fallow period increased e.g. F5 was dominated by Castanopsis tribuloides, F10—Rhus chinensis, F20—Macaranga denticulata and F30—Albizia chinensis. The changes in dominant species with respect to fallow ages in the present study could be due to large anthropogenic disturbance on the pioneer species as well as greater establishment ability of the climax species in relation to its environment, altitude and soil condition.