Fungal pathogens associated with wilting of Neolitsea cassia trees

Neolitsea cassia, a tree species, belongs to family Lauraceae, is endemic to Sri Lanka. Few planted trees of Neolitsea cassia were severely affected by wilt disease. Two fungal pathogens were consistently isolated from collar region and roots of symptomatic trees. These two fungal species were identified as Colletotrichum and Pestalotiopsis by microscopic observations of conidia and culture characters of isolates on PDA. This is the first report of Colletotrichum and Pestalotiopsis species causing tree wilting of Neolitsea cassia in Sri Lanka. Application of 25 l of fungicide, Thiram + Thiophanate Methyl, 50+30% WP (Homai) solution (1g/l) around the base of each infected plant as a soil drenching was effectively controlled wilting of Neolitsea cassia caused by both pathogenic fungi.

Undergrowth phytodiversity index in exotic and indigenous tree plots in Hoteya forest range of Sakhipur upazila under Tangail forest division, Bangladesh

This study was undertaken to know the species diversity of the monoculture plantations of exotic species Acacia auriculiformis and Eucalyptus camadulensis compared to indigenous species Shorea robusta and Mangifera indica. There are 12 sample plots (size 36x36 m) were selected from the study area following the purposive random sampling. A total of 720 quadrats (12 plots x 10 quadrats x 6 seasons) were placed in the sample plots to collect the undergrowth vegetation data over two years of 2010-11 following summer, monsoon and winter season. The average value of Shannon-Wiener diversity index was 2.65±0.16 and 3.28±0.13 that of Simpson’s diversity index was 0.87±0.02 and 0.93±0.01 and that of Margalef’s diversity index was 7.34±0.77 and 10.43±0.52 collectively in all exotic and indigenous plots, respectively. This scenario depicts that the extent of species diversity was higher in indigenous tree species plots than in exotic tree plots and the flora of the study area was highly diversified. The Shorea plots were richer in species diversity out of the four species categories of sampling plots. The index values of three diversity indices were significantly different for the exotic and indigenous tree plots, excluding Eucalyptus and Mangifera species plots, which mean the undergrowth species diversity of Eucalyptus and Mangifera species plots, were not significantly different. Adequate awareness building programs need to conduct among the local community and Bangladesh Forest Department to understand environmental degradation, the importance of conservation management of indigenous ‘Sal’ forest and significance of plant diversity in the village forest for future generations.

Influence of humanitarian assistances on ecosystem services in Bangladesh coast

The coastal ecosystem of Bangladesh is diverse and the life and livelihood of the people are largely dependent on ecosystem services (ES). The frequent natural disasters negatively influence coastal ecosystem services and consequently interrupt human life and resources. Government and non-government organizations provide humanitarian assistance to the local community to recover damages induced by disasters in coastal areas. In this research, we used participatory workshops (n=4) and face-to-face questionnaire surveys (n=131) to study the influence of humanitarian assistance on ecosystem services on the Bangladesh coast. Our study revealed prominent ecosystem services in the study area; those were provisioning services: crops, livestock, capture fisheries, freshwater; regulating services: erosion regulation, climate regulation, natural hazard regulation; cultural services: recreation and tourism, boating to the Meghna coast, migratory birds watching. The livelihood of people was heavily impacted by the disasters; however, training support guided them to manage their income by selling their commercially produced animals (e.g., cattle, goats and poultry) before disaster seasons. Humanitarian assistance for supplementary nutrient supply, sanitation and drinking water facilities influenced the unwanted extraction of natural resources from the fragile ecosystems after the disaster. Our study suggested that future research should focus on the influence of one-to-one humanitarian assistance, to what extent ES improvement through this assistance is achievable for natural disaster protection on the Bangladesh coast.

Some machining and handtool properties of tetuya koroi (Albizia odoratissima) wood

The study was conducted to determine the suitability of tetuya koroi (Albizia odoratissima) wood for furniture manufacturing i.e., planing, shaping, boring, mortising, turning, etc machining and handtool property tests of this species grown in south-east Bangladesh.. The evaluation in both machining and handtool property tests was based on the frequency of the defect-free sample. Finishing property was also determined by implementing two types of polishing materials, viz.: carpa and shellac. The defects of the sample were estimated by visual and tactile observation. The percentage of defect free samples was evaluated for each property operation and classified based on five quality grades. The study's findings mainly introduced good working properties, and tetuya koroi wood may be suitable for furniture. All properties exhibited 63 % to 76 % grade 1 and 95 % to 100 % qualified grade. The finishing property of this wood showed good quality as well.

Suitability of rubber tree (Hevea brasiliensis) for making hardboard

Rubber (Hevea brasiliensis) wood (stem and branch) chips were pulped to produce hardboard for industrial use. Hardboards were made by thermo mechanical (steaming) and chemo mechanical processes for making hardboard to assess their suitability. In the thermo mechanical process, chips under 7.03 kg/cm2 and 10.55 kg/cm2 digester pressure each for 30, 60 and 90 minutes. In the chemo mechanical (chemical pre-treatment) process, chips were soaked in 1, 2, 3% NaOH solution under atmospheric pressure at 24 hours soaking time. Hardboards were tested to determine their modulus of rupture and water resistance properties. Results showed that chemically treated boards are stronger than steam softening boards. The boards made from rubber branches are much stronger than rubber stems.

Forest tenure and rights: a constraint to community forest management in Cameroon and the REDD+ initiative

The link between Reducing Emissions from Deforestation and Forest Degradation, with the enhancement of forest carbon stock (REDD+) and Community Forest Management (CFM) as a necessary local action on the forest, is continuously being challenged. CFM has been a suitable option in achieving sustainable forest practices in the tropics. The factors that contribute to its success will likely contribute to the success of REDD+ programs in Cameroon. Nevertheless, the opportunity and challenges in integrating the two concepts to achieve the objectives require careful analysis, considering the challenges facing the country’s tenure system. This article makes use of an in-depth content analysis of several documents concerning the subject matter and tries to examine the extent to which forest tenure and rights are a constraint to CFM in Cameroon and the REDD+ Initiative and assess how these concepts can work together to achieve sustainable forest management and a reduction in deforestation and forest degradation. The assessment shows several bottlenecks and discrepancies concerning tenure rights in the community forest and carbon rights when it concerns incentive-based benefit-sharing mechanisms under the REDD+ process. It reveals that the state may likely maintain centralization of forest tenure if the issues are not clarified. The article concludes with a proposal of an urgent need for domestic legal reforms to secure forest protection achieve the objectives of international forest policy initiatives like REDD+.

Carbon stock assessment through above-ground biomass of trees at different forest composition in Mt. Malindawag, Lubilan, Naawan, Misamis Oriental, Philippines

It is documented that the amounts of carbon stored and its level of degradation in different forests compositions and different types of forest is mostly unknown, Philippines is no exemption as little was done in some places of this country. This study was conducted to assess carbon stock through above ground biomass of trees at different forest composition in Mt. Malindawag. There were three (3) 20m x 20m sample plots (quadrats) (400m2 equivalent to 0.04 ha) established as replicate plots provided with 50m intervals. Forest composition such as the Agroforestry area, mixed forest area and the Plantation forest were assessed in terms of the number of individuals, number of species, diameter, and height to calculate the biomass, tree biomass density as well as the carbon stock. Based on the results of the study conducted in different forest compositions of Mt. Malindawag, plantation forest has the highest carbon stocking rate. However, these results were not significantly different from the other forest composition. This was associated with a higher accumulated diameter, which resulted in higher biomass and eventually carbon stock. Species found in this forest composition are productive and have lesser number of individuals; therefore, there is lesser competition for resources such as light. Such a mechanism might contribute to the higher biomass and carbon stock. However, the result may not be right to other areas due to uncontrollable factors, anthropogenic and environmental factors. Hence, it is recommended to have further studies on areas where trees have similar age, species diversity index as well as stand development and site productivity for a more accurate and quantifiable carbon stock.

The Dynamics of tropical forest ecosystem with special reference to gap dynamics, regeneration and succession

The ecosystem stability in forests is highly dependent on ecological efficiency of species to the changed habitat. Thus, in forest ecosystems, the biodiversity change, interruption of migration patches, changes in soil profile, changes in habitat and watershed, and changes in wildlife status etc are the major impacts of climate change. The forest canopy is not homogenous and dense canopy cover is often interspaced with openings, where tree saplings along with shrubby vegetation co-exist. The species in the openings or fewer dens region determining the forest structure for a very long time because of the long span of tree maturity phase, sometimes centuries. New species seedlings occupy the canopy openings, most of them are light demanding, and establish the community at the risk of shade loving species present under dense canopy region. This building phase of forest is the most important part of the life cycle. The survival of seedlings and transformation to the sapling stage can be more complex due to long-term environmental factors. The regeneration dynamics of the tropical forest ecosystem is poorly understood. The details are discussed in the paper.