Vol. 5 No. 1 (2015)

Effect of Household Solid Waste on Initial Growth Performance of Acacia auriculiformis and Cedrela toona in Mycorrhiza Inoculated Soil

2015-01-01T00:00:00Z

Effect of Household Solid Waste on Initial Growth Performance of Acacia auriculiformis and Cedrela toona in Mycorrhiza Inoculated Soil Abdullah-Al-Mamun, M.M.; Billah, M.; Hossain, M.A. Solid waste disposal and management became one of the major environmental concerns in Bangladesh. Realising the problem, the present study has been undertaken with a view to find a sound and effective way of bio-degradable solid waste management. The study was carried out in the nursery of Institute of Forestry and Environmental Sciences at University of Chittagong to determine the effects of solid waste and waste inoculated with mycorrhizal soil on initial growth performance of Acacia auriculiformis and Cedrela toona. Before planting the seedlings, decomposable waste and mycorrhiza inoculated decomposable waste were placed on the planting holes. Physical growth parameters of seedlings (shoot and root length, leaf and branch number, fresh and dry weight of shoot and root and nodulation status) and the macro nutrients (N, P and K) were recorded after six months of planting. The highest performance of physical parameters was recorded in the soil treated by mycorrhiza inoculated waste. Cedrela toona was represented by maximum nutrients uptake (N-2.60%, P-0.21% and K-2.34% respectively) in the soil treated with mycorrhiza. In case of Acacia auriculiformis, N uptake was maximum (3.02%) in control while K uptake was highest (1.27%) in soil with waste and P (0.18%) uptake was highest in the soil treated with mycorrhiza inoculated waste. Highest initial growth performance was revealed by seedlings treated with mycorrhiza inoculated waste. This study suggested to use mycorrhiza and waste for plantation purposes for hygienic disposal of solid waste and to reduce cost of cultivation.

Investigation of Sawmill Management and Technology on Waste Reduction at Selected Sawmills in Moratuwa, Sri Lanka

2015-01-01T00:00:00Z

Investigation of Sawmill Management and Technology on Waste Reduction at Selected Sawmills in Moratuwa, Sri Lanka Caldera, H.T.S.; Amarasekera, H.S. The demand for sawn timber and wood-based products is rising steadily with new developments and the growing domestic consumption in Sri Lanka. Therefore, it is important to strike a balance between the increasing demand and consumption of forest resources. Thus, the key objective of this study was to investigate the effects of sawmill management and technological parameters on loss in conversion from logs to sawn timber and to compare the sawmill efficiency in private sawmills with the state timber corporation sawmill. Sawmill management and technological parameters were studied in 21 private sawmills and State Timber Corporation sawmill in Kaldemulla to evaluate the effects on loss in conversion. The selected sawmills represent all types available in Sri Lanka, i.e., frame saw, circular saw and band saw mills. Based on the results, mean percentage loss in conversion of teak and mahogany timber for all sawmills (private and State Timber Corporation) in Moratuwa found to be 53.10%. Significant differences were observed in loss in conversion values between the three categories of private sawmills as well as within sawmills of the same category. It was shown that loss in conversion values also varied with sawmill management and technological parameters such as type of machinery employed, sharpening frequency and sawyer’s experience, saw setting, availability of log alignment equipment and saw guards, oversizing and sawn timber sizes.

A Preliminary Study on Vegetation Structure and Mangrove Diversity in Irakkandy Lagoon, Trincomalee

2015-01-01T00:00:00Z

A Preliminary Study on Vegetation Structure and Mangrove Diversity in Irakkandy Lagoon, Trincomalee Krishnanantham, K.; Seneviratne, Y.B.M.C.J.; Jayamanne, S.C. The present study was carried out during the period from May to July 2014 to assess the vegetation pattern and to estimate biomass of the mangroves in Irakkandy Lagoon, Trincomalee. Five belt-transects of 10 m in width were laid perpendicular to the shoreline. Data were collected on tree diameter at breast height (dbh) and tree height from each sub-plot (100 m2) in belt transects using standard methods. Above ground biomass, basal area and relative density of the mangroves were also estimated. Diversity and evenness of each sub-plot was calculated using Shannon-Wiener diversity index and Pielou’s evenness index respectively. Results revealed that the study site is composed of 5 true mangrove species and highest density was recorded for Avicennia marina (414 trees/ha, 700 saplings/ha, 2354 seedlings/ha), followed by Lumnitzera racemosa, Excoecaria agallocha, Rhizophora apiculata and Heritiera littoralis. The greatest mangrove diversity (1.28) was observed in subplot 1 of transect 2. The least mangrove diversity (0) was found in transect 5. There is a significant difference among transects concerning the diversity and evenness (P<0.05). The results showed that Avicennia marina was the dominant species with Height (H) and dbh of 3.65±1.43 m and 5.06±1.07 cm respectively, followed by Lumnitzera racemosa (3.36±1.19 m and 5.81±1.06 cm, Excoecaria agallocha (4.92±2.45 m and 5.31±1.93 cm), Rhizophora apiculata (4.56±1.70 m and 4.89±0.96 cm) and Heritiera littoralis (8.80±0.849 m and 26.50±4.95 cm). The above ground biomass of Lumnitzera racemosa was recorded as 8334.89 kg/ha and Avicennia marina was recorded as 1361.13 kg/ha. Species diversity (H’) of whole mangrove area studied was 0.86 and evenness (E) was 0.54. It reveals that Irakkandy Lagoon consists of fairly high biological diversity (Diversity index=0.86) of mangroves and extremely valuable for stability of the ecosystem.

Biocontrol Potential of Metarhizium anisopliae (Metsch.) Sorokin (Deuteromycotina: Hyphomycetes) against Ailanthus Defoliator, Eligma narcissus (Cram.)

2015-01-01T00:00:00Z

Biocontrol Potential of Metarhizium anisopliae (Metsch.) Sorokin (Deuteromycotina: Hyphomycetes) against Ailanthus Defoliator, Eligma narcissus (Cram.) Bai, N.S.; Sasidharan, T.O.; Remadevi, O.K. Eligma narcissus is recognised as a serious pest of Ailanthus in Southern India and defoliation of Ailanthus by this pest causes apparent loss of growth increment. The common control methods for this pest is mostly insecticides and the concern about the environmental effects of chemical insecticides, has emphasised the use of environmentally more benign microbial agents. Among entomopathogens, Fungi are the most explored and often act as important natural control agents that limit insect populations. On this point of view, Bio efficacy of 25 isolates of Metarhizium anisopliae was assessed to establish their virulence against E. narcissus in the laboratory and effective formulations of two potent isolates were subsequently evaluated in the field. MIS7 and MIS13 were more effective among the different isolates evaluated against E. narcissus. The median lethal concentration (LC50) of all the isolates ranged from 6.46×105 conidia/ml to 628.92×105 conidia/ml. Median lethal concentration of (LT50) of 4.9 and 5.4 days were recorded for MIS7 and MIS13 respectively at a concentration of 1× 107 conidia/ml. Virulence tests of the isolates MIS7 and MIS13 and 0.5% Pongamia pinnata seed oil, individually and in different combinations, indicated improved efficacy of the isolates when used in combination and also when combined with seed oil. Formulations composed of “MIS7+MIS13+0.5% Pongamia pinnata seed oil” and “MIS7+MIS13” proved to be superior against E. narcissus, causing 76.30% and 93.93% mortality, respectively. Field evaluation of the formulation MIS7+MIS13+0.5% Pongamia pinnata seed oil recorded 5.79 larvae per plant resulting in 60.53% reduction of infestation while the formulation, MIS7+MIS13 showed 53.76% reduction of infestation with 6.56 larvae per plant. The observations from this study suggest the prospects of using the entomopathogenic fungus, M. anisopliae for the control of E. narcissus.