Effect of Disturbance in Tree Diversity, Carbon Stock and Regeneration in the Community Forests of Dang, Nepal

Forest is one of the most important natural resources of the ecosystem which contributes in biodiversity conservation as well as plays a significant role in maintaining the earth’s climate by sequestrating atmospheric carbon. Tropical forests are rich in biodiversity and store large amounts of carbon. The studied Bolbum Community Forest (BCF) and Brahmakumari Global Religious Forest (BGRF) lie in tropical region between the altitudes 120 and 300 m asl in Rupandehi District of Nepal. The main objective of this research was to assess and compare tree diversities and carbon stocks in two different management regimes, namely, community forest and religious forest. Stratified random sampling technique was used for data collection. The allometric equation biomass-diameter regression (Model II) was used for estimation of carbon stock of tree species while Simpson and Shannon-Wiener indices were used to measure tree species diversity. The results showed that the carbon stock value was 27.15 t.ha-1 in BCF and 40.94 t.ha-1 in BGRF. The community forest had lower value of tree carbon stock than that of the religious forest. However, tree diversity was higher in BCF (25) than in BGRF (20). Shorea robusta was found to be the single dominant species in BGRF with higher basal area (102.24 m².ha-1) and contributed 56% of the carbon stock. The contribution of carbon stock of two co-dominant tree species in BCF were 32% for Shorea robusta and 26% for Terminalia anogeissiana. There was significant (p=0.05) positive relationship of carbon stock with basal area and DBH in both forest types.

Factors affecting the tree and soil carbon stock in Shorea robusta Gaertn. forests along the elevational gradient in Eastern Nepal

The present study was accomplished to assess and compare tree diversity, carbon stock, and to find the relationship between carbon stock and tree diversity in scientifically and conventionally managed community forests (CFs) of Kanchanpur District, Nepal. A total of 94 sample plots were overlaid with a systematic random sampling method (51 plots in scientifically managed Singhapur CF and 43 plots were established in conventionally managed Kalika CF). The height and DBH of each tree were measured to calculate biomass and carbon stock. Shannon-Wiener and Simpson’s indexes were calculated for tree diversity. The data were pooled and analyzed using MS Excel and SPSS software. The values were statistically compared using a t-test. The total carbon stock and tree diversity were higher in scientifically managed CF (207.58 tons/ha and H= 0.97) than conventionally managed CF (183.72 tons/ha and H=0.85). Shorea robusta has a major contribution on total carbon stock in both CFs (Kalika: 66.34% and Singhapur: 70.43%) followed by Terminalia tomentosa (Kalika: 24.65% and Singhapur: 13.36%). The t-test did not show any significant difference for the mean values of carbon stocks and tree diversity between the CFs at a 5% level of significance. However, carbon stock showed a weak but positive relationship with species richness and negative with evenness. The result of the study recommends managing forests scientifically for increased tree diversity leading to enhanced carbon deposition.

Community-based forest management provides an opportunity to build a sustainable link with ecology for meeting future needs. A study was carried out to understand the effect of management strategies on the biodiversity, soil nutrient, and carbon stock of two community forests practiced by Jamatia (JCF) and Halam (HCF) tribes of Tripura, northeast India. The forest managed by Jamatia is community conserved, whereas the Joint Forest Management (JFM) regulation issued by the Government of India was implemented in Halam community-based forest. JCF showed higher tree diversity (2.741) than HCF (2.176), while there was no significant variation in the total number of species in these forests. Anogeissus acuminata, Schima wallichii, and Terminalia bellirica were the most dominant species in JCF and HCF. A relatively higher amount of organic matter, nitrogen, and phosphorus content was found in JCF soils. JCF showed higher carbon stock (342.9 Mg C ha–1) than HCF (158.7 Mg C ha–1). A positive and significant correlation of SOC concentration was observed with soil moisture, SOM, and soil nutrient content. The results show that both stands were at developmental stages; however, regular extraction of biomass from HCF was attributable to lower carbon stock. We found that the Jamatia communities are proactively involved in the conservation of forests and sustainable management of biodiversity under their control. The results reveal that the agent of management can play a vital role in enhancing tree diversity, soil properties, and carbon stock in community forests.

Four community-managed Sal forests in Dadeldhura district of Nepal were selected for the assessment of carbon stock. The stratified random sampling method was applied to measure the field data from 105 sample plots of 100 m2. The carbon stock of trees and shrubs was estimated using Chave allometric equations for moist forests. The study found that the community forests stored carbon stock ranging from 148.5 to 202.3 Mg ha–1 (mean: 175.5 Mg ha–1). The community forests managed for a longer duration have higher carbon stock than the community forests managed for a shorter duration. From the study, it can be concluded that these forests have been acting as a storehouse of the carbon. So, we can infer that community management has had a positive impact on increasing the carbon stock of forests and thus on the mitigation of global climate change. This study contributes to the understanding of the role of community forests in mitigating the effects of global climate change.

Multiple drivers of tree and soil carbon stock in the tropical forest ecosystems of Bangladesh

Forest biomass and carbon management are central to climate change mitigation, particularly in countries where community forestry plays a major role. In Nepal, community forests cover more than 2.4 million ha and are increasingly linked to REDD+ initiatives, making it important to understand how carbon stocks and biodiversity vary across environmental gradients. This study assesses patterns of aboveground biomass, carbon stock, and tree species diversity along an elevational gradient (245–3,549 m a.s.l.) in the Charnawati and Kayarkhola watersheds of Nepal’s central Himalayas. Data from permanent sample plots established in community forests were used to estimate tree biomass, carbon stocks, and species importance value index (IVI). The results indicate strong altitudinal variation in forest structure and composition. Aboveground biomass was highest at lower elevations (500–1,000 m a.s.l.), reaching 344.97 t ha⁻¹, whereas tree density peaked at mid-elevations (2,000–3,000 m a.s.l.) with up to 1,600 individuals ha⁻¹. Species dominance shifted from Shorea robusta at lower elevations to mixed Quercus–Rhododendron forests at mid-elevations and conifer-dominated stands at higher elevations. Regression analyses revealed elevation-specific relationships, with altitude positively influencing carbon stocks at low (<500 m a.s.l.) and high (2,000–3,000 m a.s.l.) elevations, while tree height showed a positive association with carbon stocks only at 1,000–2,000 m a.s.l. However, all models exhibited low explanatory power (R² < 0.11), indicating the influence of multiple interacting factors. Overall, the findings suggest that carbon–biodiversity relationships in community forests are not uniform but are mediated by elevation-specific ecological conditions. These insights highlight the need for elevation-sensitive REDD+ and forest management strategies to enhance both climate mitigation and biodiversity co-benefits.

Nepalese community forests are globally recognized for sustainable forest management and improving the livelihoods of forest-dependent communities, but their contribution to carbon sequestration in trees and soil is rarely studied. This study was performed to understand the effect of management practices on carbon stock of two community forests (CFs) - Taldanda (managed) and Dangdunge (unmanaged) - dominated by Sal (Shorea robusta) in the mid-hills of Nepal. Twenty-one concentric sample plots, each of 250 m2, were laid out in each forest to estimate different carbon pools and a stratified random sampling intensity of 0.5% used to collect data. Results showed significant (p<0.05) differences in above and below-ground biomass and carbon sequestration potential between the two CFs. The managed and unmanaged forests had total carbon stock of 269.3±27.4 and 150.0±22.7 ton/ha, respectively, demonstrating 1.79 times higher carbon stock in the former than the latter. The managed forest had significantly (p<0.05) greater mean soil organic carbon (SOC) stock than the unmanaged forest. The SOC was highest in the upper soil layer (0-10 cm), with a steady decrease as the soil depth increased. All other measured carbon pools values were higher in managed compared to unmanaged forest. The difference in carbon stock was due to the manipulation of different forest management activities, including thinning, timber extraction, fire control, grazing, and fuel wood/fodder extraction. The study suggests that the implementation of proper forest management would be necessary for enhancing carbon stock in forest trees and soils.

A study was conducted to estimate the of above ground and below ground carbon stocks in trees, shrubs, herbs/grasses and leaf litter in Kankali community forest of Chainpur Village Development Committee (VDC), Chitwan district and Tibrekot community forest of Hemja Village Development Committee (VDC), Kaski district of Nepal. The tree volume was calculated by using allometric equation with the help of height and diameter (non-destructive method). Herbs/grasses, shrubs and leaf litters biomass were estimated in laboratory by oven dry method and some conversion and unitary methods. Carbon stocks of vegetation as well as other category were estimated by considering default value as 0.43 of the total biomass. The total forest biomass was estimated 147.01 t/ha and 98.28 t/ha in Shorea robusta and Schima- Castanopsis dominated forests respectively. S. robusta dominated forest has occupied the carbon stocks of 63.22 t/ha, and out of this above ground carbon stock was 48.93 t/ha (77%) and below ground carbon stock was 14.29 t/ha (23%) followed by Schima-Castanopsis dominated forest having total carbon stock 42.26 t/ha, which contain in above ground 30.60 t/ha (72%) and in below ground 11.66 t/ha (28%). The total carbon content in S. robusta dominated forest including all categories was 20 % higher as compared to the Schima-Castanopsis forest. Kankali community forest was having higher tree density, dbh and height of trees as compared to Tibrekot community forest.

This study assessed the biomass and carbon stocks above and below ground in a community forest in central Nepal that is dominated by Sal (Shorea robusta). A basic random sample design with a 2% sampling intensity and 500 m² circular plots was used to gather field data from Block 1 of the Piple Pokhara Community Forest, Makawanpur District, between October 2021 and March 2022. Tree height and diameter at breast height (DBH) were measured, and standard allometric equations were used to determine biomass. A total of 78 individual trees were measured across the eight sample plots. With a mean height of 13.18 m and a mean DBH of 20.66 cm, the forest showed moderate structural variability. The average total biomass per tree was 315.63 kg, with mean above-ground and below-ground biomass of 263.03 kg and 52.61 kg, respectively. Above-ground components accounted for the highest share of the corresponding mean carbon stocks, which were 0.12 tons above-ground, 0.02 tons below-ground, and 0.15 tons overall per tree. Plot-to-plot variations in carbon stocks ranged from 0.11 to 0.20 tons per tree, primarily due to variations in tree size. The findings highlight the role of community forests in Nepal's efforts to mitigate climate change and account for carbon emissions. They show that the community forest serves as an efficient local carbon sink and that better forest management that focuses on stand structure could further enhance its carbon sequestration potential.

Understanding the long-term effects of logging disturbances on the linkages between tree diversity and carbon stocks is important for conservation efforts and mitigation of global climate change. This study was carried out in unlogged and 14–29 years post-logged forests in the Bia Conservation Area in southwest Ghana. The study results showed that both large (diameter at breast height or dbh ≥ 10 cm) and smaller (dbh ≤ 10 cm but ≥5 cm) tree diversity increased significantly in logged forest compared with unlogged forest while tree dominance was similar between the two land-use types. Tree species guild composition was significantly different due to the higher proportion of pioneer species of large trees in logged forest and shade bearer species of smaller trees in the unlogged forest. Total mean carbon stock was 322.8 Mg C per ha [95% Confidence Interval (CI): 191.6–443.8] for logged forest and 211.2 Mg C per ha (95% CI: 196.9–228.0) for unlogged forest, although no significant difference was detected (p > 0.05). There was a significant interaction (p < 0.01) between ecological guilds and land use types in total tree-stored carbon stocks. The results of the study showed that logging has comparatively long-term effects on tree diversity while its effect on carbon stocks might only be short term. The findings from this study underscore the need for more comparative data from other areas in West Africa.

Tree species diversity and spatial distribution of carbon stock in forests under different management regimes in Nepal's Western Terai Arc Landscape

The study entitled “Quantification of above and below ground carbon stocks in selected community forests of Nepal (A case from Community Forest and Government Managed Forest of Sindhupalchok, Nepal)” was aimed at to estimate the above ground and below ground carbon stock of Selang Manju Community Forest and LakpaDorje Government Managed Forest of Sindhupalchok district, Nepal. Out of the total 196.16 ha Community forest area 1.5 ha i.e. 0.76% area was selected for the forest inventory. All together there are 30 plots in the community forest and other 30 plots in the government-managed forest.Primary and Secondary data were collected and analyzed by using the t test. Tree carbon stock in Government managed forest was found to be higher with 77.86 ton/ha than CF with 74.39 ton/ha. Tree carbon stock of Government managed forest is very high because in the National Forest there were lots of old trees which have carbon storage but they do not have sequestrating capacity anymore. Sapling carbon stock was found to be lower in government managed forest with 0.92 ton/ha than in community forest with 0.97 ton/ha. LHG carbon was found to be higher 1.31 ton/ha in government-managed forest than CF with CF with 1.16 ton/ha. Dead wood carbon stock in Government managed forest was found to be higher with 12.01 ton/ha than CF with 11.48 ton/ha. The below ground carbon consists of Root Carbon. The root carbon of government managed forest was found to be higher with 16.58 ton/ha than community forest with 15.84 ton/ha. The soil organic carbon was found to be 170.54 ton/ha in community forest and 172.18 ton/ha in government managed forest. Total carbon stock of Government managed forest was found to be higher with 280.86 ton/ha than community forest with 274.28 ton/ha. The total carbon stock of the community forest is 274.28 ton/ha similarly the total carbon stock of the government managed forest 280.86 ton/ha. The total carbon in the community forest is 53802.76 ton similarly the total carbon in the government managed forest is 57576.30 ton. The total carbon in the community forest is less than the government managed forest. There is significance difference between mean above ground (Shoot, LHG, and dead wood) carbon stock of CF and GMF however there is significance difference between mean sapling carbon stock of CF GMF. There is significance difference between mean below ground (Root and Soil) carbon stock of CF and GMF at 5% level of significance.

Tree biomass and carbon stock assessment of subtropical and temperate forests in the Central Himalaya, India

Aim: This study aims to evaluate tree diversity and carbon stocks across diverse land-use systems within the heterogeneous landscape of the GKVK Biodiversity Heritage Site, Bengaluru. Methodology: A random quadrat sampling method (135 quadrats of 20 m2) was used to measure tree diversity (Shannon (H´), Simpson (1-D), species richness) and population structure (basal area, stem density, girth class). Carbon stocks were estimated using non-destructive allometric equations based on tree diameter and wood density. Results: During the course of study, 1,611 individuals from 75 species were reported. Gardens exhibited the highest biodiversity (H´ = 3.35; 1-D = 0.95; species richness = 56) and stem density (370 individuals ha-1) whereas agricultural lands showed the lowest diversity (H´ = 1.46;1-D: 0.61; species richness =13) and stem density (67.19 individuals ha-1). Plantations with the highest stem density (488.89 individuals ha-1) contributed significantly to carbon sequestration, boasting the maximum average basal area (12.38 m2 ha-1) and carbon stock (49.39 Mg ha-1). A strong correlation (r=0.985, p&lt;0.0001) between basal area and carbon stock underscores the role of forest structure in carbon storage. Medium- and large-diameter trees were identified as key contributors to carbon stock. Interpretation: This study revealed that tree diversity and carbon stocks vary significantly across land-use systems, with gardens exhibiting the highest biodiversity and plantations contributing the most to carbon sequestration. Medium- and large-diameter trees are crucial for carbon storage, highlighting the importance of conserving mature trees and improving biodiversity. These findings offer insights for promoting sustainable land management and enhancing carbon capture. Key words: Carbon stock, Diversity, Heterogenous landscapes, land use systems