Earticle

This study was conducted to investigate the effect of different pre-sowing treatments of seeds on germination and growth performance of native threatened tree species Quercus gomeziana A. Camus at the nursery of Chittagong University, Bangladesh. Furthermore, seedling growth attributes under different doses of fertilizer (urea) was also experimented to find the best dose of fertilizer on this tree species at the nursery stage for better field level growth. Seeds were placed to six pre-sowing treatments e.g. control (PT0), treated with sand paper rubbing (PT1), nicking (PT2), seeds immersed in cold water for 48 hours (PT3), seeds immersed in cold water for 7 days (PT4) and seeds sown at propagator house with increased temperature (PT5). It was found from the study that germination was started earlier (at 31 days) in treatments sand paper rubbing (PT1) and nicking (PT2). The highest germination percentage (93%) was in PT1 followed by 86% in seeds immersed in cold water for 7 days (PT4) and 80% in PT0 (control). Germination percentage was observed least (63%) in PT2 even though germination started earlier. For fertilizer dose experiment to seedlings at the nursery level, treatment FT1: 100 kg/ha (0.33679 g urea/pot/seedling) comparing with other treatments FT0: 0 kg/ha (Control), FT2: 200 kg/ha (0.67358 g urea/pot/seedling), FT3: 300 kg/ha (1.01037 g urea/pot/seedling) showed better performance in case of collar diameter (6.74 mm), number of leaves, shoot dry weight (19.74), total dry weight (28.16 g), total fresh weight (67.96 g), volume index (3904.82), sturdiness (127.69). Finally, it can be concluded that Quercus gomeziana seedlings revealed better performances under the treatment FT1 in growth and biomass production. Findings of this study will be helpful to take decision on organic fertilizer dose application to seedlings of Q. gomeziana for large scale plantation and conservation of this species.

Tree size distribution modelling is an integral part of forest management. Most distribution yield systems rely on some flexible probability models. In this study, a simple finite mixture of two components two-parameter Weibull distribution was compared with complex four-parameter distributions in terms of their fitness to predict tree size distribution of teak (Tectona grandis Linn f) plantations. Also, a system of equation was developed using Seemingly Unrelated Regression wherein the size distributions of the stand were predicted. Generalized beta, Johnson’s SB, Logit-Logistic and generalized Weibull distributions were the four-parameter distributions considered. The Kolmogorov-Smirnov test and negative log-likelihood value were used to assess the distributions. The results show that the simple finite mixture outperformed the four-parameter distributions especially in stands that are bimodal and heavily skewed. Twelve models were developed in the system of equation-one for predicting mean diameter, seven for predicting percentiles and four for predicting the parameters of the finite mixture distribution. Predictions from the system of equation are reasonable and compare well with observed distributions of the stand. This simplified mixture would allow for wider application in distribution modelling and can also be integrated as component model in stand density management diagram.

This study aimed to figure out and compare the increment of biomass by thinning intensity focused on the plantation of the two major coniferous species (Larix kaempferi and Pinus koraiensis) of South Korea. The inventory interval was three years under the effects of three types of thinning treatments; control (no thinning), light (20% thinning) and heavy (40% thinning). The results showed standing biomass increment of both species decreased as thinning intensity increased (heavy＜light＜control). Biomass increment of each tree compartment (roots, stem, branches and foliage) also followed the increment pattern of the total biomass. In contrast, the rate of biomass growth increased as increasing thinning intensity (heavy＞light＞control). Meanwhile, the lowest of on-site biomass changes occurred in the control plot, and the greatest was in the heavy thinning plot because thinning was involved with leaving the felling residual biomass (leaves, branches and roots) on the site. According to the results from this short-term study, unthinned stands is preferable for maximizing standing biomass as well as carbon sequestration. However long-term investigation should be considered in order to see more clear results.

Area exclosure is a widely practiced intervention of restoring degraded lands though its impact in sequestering terrestrial and soil carbon is scanty. The study was initiated to investigate the effect of exclosure of different ages on carbon sequestration potential of restoring degraded dryland ecosystems in eastern Tigray, northern Ethiopia. Twelve plots each divided into three layers were randomly selected from 5, 10 and 15 years old exclosures and paired adjacent open grazing land. Tree and shrub biomasses were determined using destructive sampling while herb layer biomass was determined using total harvest. The average total biomass obtained were 13.6, 24.8, 27.1, and 55.5 Mg ha-1 for open grazing, 5 years, 10 years, and 15 years exclosures respectively. The carbon content of plant species ranged between 48 to 53 percent of a dry biomass. The total carbon stored in the 5 years, 10 years and 15 years age exclosures were 39 Mg C ha-1, 46.3 Mg C ha-1, and 64.6 Mg C ha-1 respectively while in the open grazing land the value was 24.7 Mg C ha-1. Carbon stock is age dependent and increases with age. The difference in total carbon content between exclosures and open grazing land varied between 14.3-40 Mg C ha-1. Although it is difficult to extrapolate this result for a longer future, the average annual carbon being sequestered in the oldest exclosure was about 2.7 Mg C ha-1 yr-1. In view of improving degraded area and sequestering carbon, area exclosures are promising options.

Vegetation carbon sequestration and regeneration are the two major parameters of forest research. In this study, we analyzed the vegetation carbon stock and regeneration of community-managed pine plantation of Kathmandu, central Nepal. Vegetation data were collected from 40 circular plots of 10 m radius (for the tree) and 1m radius (for seedling) applying a stratified random sampling and nested quadrat method. The carbon stock was estimated by Chave allometric model and estimated carbon stock was converted into CO2 equivalents. Density-diameter (d-d) curve was also prepared to check the regeneration status and stability of the plantation. A d-d curve indicates the good regeneration status of the forest with a stable population in each size class. Diversity of trees was very low, only two tree species Pinus roxburghii and Eucalyptus citriodora occurred in the sample plots. Pine was the dominant tree in terms of density, basal area, biomass, carbon stock and CO2 stock than the eucalyptus. The basal area, carbon stock and CO2 stock of forest was 33±1.0 m2 ha-1, 108±5.0 Mg ha-1 and 394±18 Mg ha-1, respectively. Seedling and tree density of the plantation was 4,965 ha-1 and 339 ha-1 respectively. The forest carbon stock showed a positive relationship with biomass, tree diameter, height and basal area but no relationship with tree density. Canopy cover and tree diameter have a negative effect on seedling density and regeneration. In conclusion, the community forest has a stable population in each size class, sequestering a significant amount of carbon and CO2 emitted from densely populated Kathmandu metro city as the forest biomass hence have a potentiality to mitigate the global climate change.

A “Scenic Site” is an official heritage category legally defined as a “scenic site of outstanding artistic value with excellent scenic views.” However, the subjective interpretation of the term causes several problems. This study suggested a systematic, organized process of designating a listed area as a scenic site after careful and detailed quantitative and qualitative analysis. Indicators were identified for each of the two analyses, and then scored and weighted. Quantitative indicators were distributed within 5 points for each indicator. Water, which is a natural indicator, based on distance from river boundaries. Forest landscapes were assigned in consideration of forest physiognomy and age class. Land use was allocated in consideration of land cover type and, in case of development site, ‘-’ score was assigned. Cultural heritage conservation area, which is historical and cultural indicator, was distributed by distance within a maximum of 500 meters. Visibility, an indicator of landscape value, was assigned according to the frequency of visibility. The weight of each indicator was calculated by considering the value of each item. The weight of distribution of cultural resources is relatively high, while other items were set the same. In case of land use, however, ‘-’ score was given according to the grade. Qualitative indicators, on the other hand, were considered terrain, landscape zone, ownership, intellectual boundary, and land category. The applicability of the proposed process and method was examined by applying the existing methods and criteria used for designating scenic spots. Opinions of subject-matter experts were incorporated in the identification of the indicators and in the result review stage. In the future, it is necessary to apply this method while designating scenic sites so as to establish an objective, scientific designation process.

In this study, basic data with respect to the introduction of Hipphophae rhamnoides L. and its cultivation in Korea could be obtained. According to the size of the plug cell tray, Chinese origin’s rate of seed germination was relatively high in 128 plug cell tray, and growth was vibrant in 50 plug cell tray. The germination and growth of Russian origin seeds showed that they were relatively effective in 50 plug cell tray and with respect to soil environment, TKS-2 soil with untreated shading relatively promoted both germination and growth for Chinese origin, the rate of germination was high in bed soil for horticulture and growth result was good in TKS-2 in the case of Russian origin. It was confirmed that the germination rate of Chinese origin H. rahmnoides L. was highest in untreated shading and the shoot growth was vibrant in 70% shading while the growth in roots was vibrant in the untreated shading. In the Russian origin, H. rhamnoides L. the germination rate in 30% and 70% shading was about 50% which was higher than that in the untreated shading and general growth was vibrant in 30% shading.

Ethanol fermentation of the enzymatic hydrolysates from the products pretreated using 1-ethyl-3-methyl-imidazolium acetate ([EMIM]Ac) and its co-solvents with dimethylformamide (DMF) was conducted using Saccharomyces cerevisiae (D452-2). The optical density change due to the yeast cell growth, the consumption amount of monosugars (glucose, xylose), the concentration of acetate, and ethanol production yield were investigated. The co-solvent system lowered inhibition of the growth of the cells. The highest concentration of glucose (7.8 g/L) and xylose (3.6 g/L) was obtained from the enzymatic hydrolysates of the pretreated product by pure [EMIM]Ac. The initial concentration of both monosugars in the enzymatic hydrolysates was decreased with increasing fermentation time. Ethanol of Approximately 3 g/L was produced from the enzymatic hydrolysates by pure [EMIM]Ac and co-solvent with less than 50% DMF.