Diversity and abundance of some insect fauna in Bhawal and Madhupur Sal forests of Bangladesh

The abundance and diversity of insect fauna were studied from two deciduous sal forests of Bhawal and Madhupur located at central part of Bangladesh. A total of 544 individuals of insects of 61 species belonging to 54 genera, 33 families and 11 orders have been identified with Hymenoptera (31%) as the dominant order in species richness followed by Coleoptera (13%), Orthoptera (11%), Diptera (10%), Hemiptera (8%), Lepidoptera (8%), Odonata (8%), Homoptera (3%), Isoptera (3%), Neuroptera (3%) and Dictyoptera (2%). Bhawal scores higher Shannon-Weaver diversity index (Hʹ=3.725) compared to Madhupur (Hʹ=3.340). The Bhawal Sal Forest with the collected 341 (63%) insects and identified 53 (59%) species belonging to 10 orders was found more diverse in species richness than the Madhupur Sal Forest with 37(41%) species belonging to 11 orders identified from the collected 203 (37%) insect samples. Insects of the order Neuroptera were not recorded from Bhawal. Off the 61 species, 29(48%) species were common in both the forests, 24(39%) species were exclusive to Bhawal and eight (13%) species were exclusive to the Madhupur Sal Forest. Apis cerana of Hymenoptera was identified as the dominant species having 9% of the identified samples followed by dipteran species Musca domestica with 6% of the samples. Among the insect species 30 (49%) species were found playing beneficial role as biological control agents, predators, pollinators, honey producers and also organic debris recycler. On the other hand, 31(51%) species were found to be harmful causing damage to forest vegetation as well as human and wildlife at variable degrees. J. Biodivers. Conserv. Bioresour. Manag. 2021, 7(1): 11-24

Biomass and Carbon Stock in the Sal (Shorea robusta) Forest of Dang District Nepal

The study was conducted to find the net carbon stock in the Sal (Shorea robusta) forest in Bagdaila Chisapani community forest of Dang district, Nepal. The inventory was done by a stratified sampling technique with 0.5% sampling intensity taking into account the woody plants with ≥ 5cm DBH. A total of 49 sample plots of radius 8.94m and 5.64 were established to measure tree biomass and sapling biomass respectively in the forest. The mean above-ground carbon (AGC) was 160.4 t ha-1 and the mean below-ground carbon (BGC) was 24.1t ha-1. The mean total carbon stock in the study area was estimated to be 99.02 t ha-1; of which maximum carbon stock of 143.51 t ha-1 was found in block number 5. Sal was the major tree species in the CF. The biomass and carbon content in this forest is found quite low as compared to other studies in the Sal forest and other tropical forests which were due to the presence of tree stands of less diameter and height. This study would be helpful in the long-term management of forests, planning, and research purposes. The data from this study could also be taken as a reference document for the participation of community forests in carbon accounting under the REDD+ scheme in Nepal.

Fire Drivers Affecting Forest Fire Occurrences in the Tropical Mixed Broad-leaved Forests of Nepal

Forest fires triggered by various natural and anthropogenic drivers are increasing and threatening forest ecosystems across the globe. In Nepal, the high value Tropical Mixed Broad-leaved Forests are prone to fire caused by both natural and anthropogenic drivers. Thus, understanding fire drivers and their effect is important for the sustainable forest fire management. However, the preceding studies on forest specific fire drivers and their effect are limited. This research has identified the fire drivers and assessed their effect to fire occurrences in the Tropical Mixed Broad-leaved Forests of Nawalparasi District, Nepal. Fire drivers were identified and prioritized by participatory approaches. The fire incidences and burnt areas were obtained from the MODIS fire data (2001–2017). The results revealed altogether 20 drivers including eight natural and 12 anthropogenic. Based on the public perception and magnitude of forest fire, among the natural drivers, temperature, precipitation, forest fuel, aspect, elevation and slope were the major drivers. Likewise, among the anthropogenic drivers, forest distance from roads and settlements showed significant effect. The natural drivers, ambient temperature >30ºC and annual precipitation <2400 mm, revealed signi-ficant impacts on forest fire. Likewise, forests situated at lower elevation (<500 m), and southern and eastern aspects were highly vulnerable to fire. Considering anthropogenic drivers, forest lying within 500 m from the roads and settlements were highly vulnerable to fire. Among the forest types, the Hill Sal Forest was more affected. Future strategies should address the major fire drivers, construction of adequate fire lines and conservation ponds for the sustainable forest management.

Fuel Briquettes from Sal (Shorea robusta) Forest Litter as an Alternative Cooking Fuel

Sal (Shorea robusta) forest leaf litter strongly influences seed germination and seedling survivorship. Therefore, it is crucial to open up the litter layer in such a forest with abundant leaf litter. Briquetting of Sal forest leaf litter can be an option for its management and meet the increasing energy demand. This research work is performed to quantify the amount of Sal forest litter and study the briquette’s combustion properties. The study was carried out in the Namuna Community Forest of Jhapa district. The average weight of leaf litter in the field was observed to be 851 g/m2 . Five varieties of briquettes were produced using different briquetting technologies. Proximate analysis results, calorific value and water boiling tests show these briquettes have good fuel characteristics and can be used as alternative cooking fuel.

Carbon Stock and Respiration of Rhizosphere Soils of Sal (Shorea Robusta Roxb. Ex. Gaertn. F.) In Relation To Some Environmental Variables of Different Sal Forest Stands of Bangladesh

Effects of some environmental variables (moisture, temperature, pH) on the carbon stock and respiration in the rhizosphere soil of Sal (Shorea robusta Roxb. ex. Gaertn. f.) of 11 different Sal forest stands situated in Cumilla, Gazipur, Sherpur, Modhupur, Dinajpur and Rangpur of Bangladesh were assessed. Soil samples were collected from two layers (upper layer, 0 - 15 cm and lower layer, 15–30 cm depth). During February 2019, samples were collected from Kotbari and Rajeshpur of Cumilla and during June 2019, samples were collected from the rest of the stands. The values of different variables showed fluctuations, e.g. moisture content (11.87 - 38.78%), pH (4.73 to 6.03), conductivity (63.13 - 248.83 μS/cm), soil organic carbon (135.43 - 1263.53 ton/ha) and respiration (75.95 - 91.8 mg CO2/g soil) respectively. Rates of respiration increased where pH remained 4 to 6 and the temperature 20 to 34ºC. Rate of respiration also increased when the amount of moisture content and carbon stock decreased. This research will help to understand the role of environmental factors on the variability of soil C dynamics in the natural Sal forest areas of Bangladesh. Bangladesh J. Bot. 50(3): 685-693, 2021 (September)

Wild Edible Plants of Dhankuta, Eastern Nepal

The Dhankuta district, situated in the Eastern part of the country, is a hot spot for floral diversity. The vegetation zone ranges from sub tropical Sal forest to cool temperate alpine forest. The study of wild edible plant of this area was an attempt to highlight the types of wild edible plants found and their mode of use in local people. Present study records 132 species of wild edible plants belonging to 63 families and 103 genera. Fruits are the most common edible parts of the wild edible plants followed by leaves, young shoot, root or tuber, seeds, flower, whole plants, bark, nectar, nuts, inflorescence and buds.

Species Diversity, Soil Nutrients Dynamics and Regeneration Status of Sal (Shorea robusta) Forests in Western Himalayan Region of India

Sal (Shorea robusta) forest is found in an extensive array of conditions in Western Himalaya. It has been heavily used for commercial purposes. Thus, we did a study to gather the information on sal forests occupying a broad range of the Rajaji Tiger Reserve which spans across an extensive range in the Western Himalaya. We tested the species diversity, soil nutrients status, and regeneration potential of the Sal forest. Vegetation was sampled in 10 transects zone of 20×20 m2 plots covering an area of 10.0 ha area. Trees, saplings, seedlings, shrubs, and herbs were sampled along the transects in the Chilla forest division of the tiger reserve. Samplings were done every 200 m along the transect with the help of the Nested quadrat method. Altogether 64 species were recorded: 24 trees, 12 shrubs, and 28 herbs. Environmental variables like pH, organic carbon, total nitrogen, available potassium, available phosphorous, and soil texture were also recorded to observe the effects of these environmental variables into diversity attributes. The Shannon Weiner index for trees was 1.350, for saplings 1.774, for seedlings 1.679. For shrub species, it was1.96. The Shannon Weiner index for herbaceous species in the rainy season was 2.8, in winter it was 2.36 whereas in summer it was 2.46. We concluded that the management of sal has enhanced the diversity and soil nutrients dynamics in the study area. Sal diversity also has enhanced the growth of co-dominant species like Mallotus philippensis, Aegle marmelos, Listea chinensis, Naringi crenulata, Ehretia laevis, Cassia fistula, etc. in the study area. Although we did not find any seedlings of the sal during the present study, the regeneration potential of sal forest increasing with a greater number of associated species provide a favorable environment for sal species.

Cataloguing the bacterial diversity in the active ectomycorrhizal zone of Astraeus from a dry deciduous forest of Shorea

The plant microbiome has been considered one of the most researched areas of microbial biodiversity, yet very little information is available on the microbial communities prevailing in the mushroom's ectomycorrhizosphere. Ectomycorrhizal symbioses often result in the formation of a favourable niche which enables the thriving of various microbial symbionts where these symbionts endorse functions, such as quorum sensing, biofilm formation, volatile microbial compound (VOC) production, regulation of microbial gene expression, symbiosis and virulence. The identification of hidden uncultured microbial communities around the active ectomycorrhizal zone of Astraeus from dry deciduous sal forest of Jharkhand, India was carried out using MinION Oxford Nanopore sequencing of 16S rRNA amplicons genes. High richness of Operational Taxonomic Units (1,905 OTUs) was observed. We recorded 25 distinct phyla. Proteobacteria (36%) was the most abundant phylum, followed by Firmicutes (28%), Actinobacteria (10%) and Bacteroidetes (6%), whereas Gammaproteobacteria was the most abundant class of bacterial communities in the active ectomycorrhizal zone. The ectomycorrhizosphere soil has abundant phosphate-solubilising bacteria (PSB). This is the first report of the ectomycorrhizosphere microbiome associated with Astraeus.