2025-04-10 2014, Volume 25 Issue 2

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  • Wei Tang , Anna Y. Tang

    Transgenic trees as a new source for biofuel have brought a great interest in tree biotechnology. Genetically modifying forest trees for ethanol production have advantages in technical challenges, costs, environmental concerns, and financial problems over some of crops. Genetic engineering of forest trees can be used to reduce the level of lignin, to produce the fast-growing trees, to develop trees with higher cellulose, and to allow the trees to be grown more widely. Trees can establish themselves in the field with less care of farmers, compared to most of crops. Transgenic crops as a new source for biofuel have been recently reviewed in several reviews. Here, we overview transgenic woody plants as a new source for biofuel including genetically modified woody plants and environment; main focus of woody plants genetic modifications; solar to chemical energy transfer; cellulose biosynthesis; lignin biosynthesis; and cellulosic ethanol as biofuel.

  • Antonio Carlos Ferraz Filho , José Roberto Soares Scolforo , Blas Mola-Yudego

    We review the management of Eucalyptus species under a coppice-with-standards (CWS) silvicultural system. CWS management results in product diversification, permitting production of small and large scale timber from the same stand. Eucalyptus species are suitable candidates for CWS management because: there are large worldwide plantation areas, sprouting capacity is high, and eucalypts are multipurpose species. We discuss (1) short rotation Eucalyptus coppice management for energy and pulping and (2) Eucalyptus seedling management for solid wood products. We review the literature and discuss experiences with Eucalyptus managed under the CWS system. We also assess projects dealing with Eucalyptus coppice management, stand density regulation, pruning, and stand and wood quality. The growth environment of the standard trees (heavy competition up to the first harvest, free growth afterwards) coupled with long rotations (>20 years) results in high quality logs for solid wood products. Early pruning should be applied to enhance wood quality. We propose a system for the silvicultural management of Eucalyptus under the CWS system, elaborating on the consequences of initial planting density, site productivity, and standard tree densities as well as timing of basic silvicultural applications.

  • Fernando Reboredo , João Pais

    Portugal’s forests in the 12th century were dominated by the Fagaceae represented by Quercus and Castanea, and several pine species. From the 12th century onwards, forests underwent changes in their management starting with protection and ultimately leading to intense exploitation. The massive naval construction during the maritime expansion (mainly in the 15th–16th centuries) involved felling of approximately 5 million trees mainly Quercus suber, Pinus pinea and other Quercus species. Cumulative fuel-wood consumption of 959 Mm3 during 1300–1854 was attributed to demographic expansion while the deforestation rate during 1636–1854 accounted for a minimum of 72.6% and a maximum of 96% of total forest cover. The volume of timber used in railway sleepers from 1856 onwards might have reached 0.5 Mm3. The last quarter of the 20th century increased the forest cover of Portugal through the World Bank program of Eucalyptus globulus reforestation.

  • Nguyen Hong Hai , Kerstin Wiegand , Stephan Getzin

    Ecological interactions of species and thus their spatial patterns may differ between homogeneous and heterogeneous forests. To account for this, techniques of point pattern analysis were implemented on mapped locations of tree individuals from two 1-ha tropicalforest plots in Vietnam. We analyzed the effect of environmental heterogeneity on tree distributions; spatial distribution patterns of dominant species; inter-specific associations; and conspecific associations between life stages. Our analyses showed that: environmental conditions were homogeneous at plot 1 but heterogeneous at plot 2; in both plots, all six dominant species were aggregated at various scales up to 30 m, and tree species were aggregated at larger scales in the homogeneous site than in the heterogeneous site; attraction between pairs of species was remarkably higher at the homogeneous site while negative associations were more frequent in the heterogeneous site; some species, H. kurzii, T. ilicifolia (homogeneous plot) and D. sylvatica, S. wightianum (heterogeneous plot), showed a lack of early life-stage individuals near conspecific adults. Moreover, additional clustering of young individuals was independent from conspecific adults, except D. sylvatica in both sites. These findings are consistent with the Janzen-Connell hypothesis. Overall, habitat heterogeneity influences spatial patterns and inter-specific associations of the tree species and evidences of self-thinning are shown in most species.

  • Chang Liu , Lianjun Zhang , Fengri Li , Xingji Jin

    Heilongjiang province is the largest forest zone in China and the forest coverage rate is 46%. Forests of Heilongjiang province play an important role in the forest ecosystem of China. In this study we investigated the spatial distribution of forest carbon storage in Heilongjiang province using 3083 plots sampled in 2010. We attempted to fit two global models, ordinary least squares model (OLS), linear mixed model (LMM), and a local model, geographically weighted regression model (GWR), to the relationship between forest carbon content and stand, environment, and climate factors. Five predictors significantly affected forest carbon storage and spatial distribution, viz. average diameter of stand (DBH), number of trees per hectare (TPH), elevation (Elev), slope (Slope) and the product of precipitation and temperature (Rain_Temp). The GWR model outperformed the two global models in both model fitting and prediction because it successfully reduced both spatial autocorrelation and heterogeneity in model residuals. More importantly, the GWR model provided localized model coefficients for each location in the study area, which allowed us to evaluate the influences of local stand conditions and topographic features on tree and stand growth, and forest carbon stock. It also helped us to better understand the impacts of silvicultural and management activities on the amount and changes of forest carbon storage across the province. The detailed information can be readily incorporated with the mapping ability of GIS software to provide excellent tools for assessing the distribution and dynamics of the forest-carbon stock in the next few years.

  • A. K. Joshi , P. K. Joshi , T. Chauhan , Brijmohan Bairwa

    Intense anthropogenic exploitation has altered distribution of forest resources. This change was analyzed using visual interpretation of satellite data of 1979, 1999 and 2009. Field and interactive social surveys were conducted to identify spatial trends in forest degradation and data were mapped on forest cover and land use maps. Perceptions of villagers were compiled in a pictorial representation to understand changes in forest resource distribution in central Himalaya from 1970 to 2010. Forested areas were subject to degradation and isolation due to loss of connecting forest stands. Species like Lantana camara and Eupatorium adenophorum invaded forest landscapes. Intensity of human pressure differed by forest type and elevation. An integrated approach is needed to monitor forest resource distribution and disturbance.

  • Gustavo Perez-Verdin , Marco Antonio Marquez-Linares , Maricela Salmeron-Macias

    In Mexico, forest fires are strongly influenced by environmental, topographic, and anthropogenic factors. A government-based database covering the period 2000–2011 was used to analyze the spatial heterogeneity of the factors influencing forest fire size in the state of Durango, Mexico. Ordinary least squares and geographically weighted regression models were fit to identify the main factors as well as their spatial influence on fire size. Results indicate that fire size is greatly affected by distance to roads, distance to towns, precipitation, temperature, and a population gravity index. The geographically weighted model was better than the ordinary least squares model. The improvement of the former is due to the influence of factors that were found to be non-stationary. These results suggest that geographic location determines the influence of a factor on fire size. While the models can be greatly improved with additional information, the study suggests the need to adopt fire management policies to more efficiently reduce the effect of anthropogenic factors. These policies may include more training for landowners who use fire for clearing, closure of roads, application of thinning, prescribed burning, and fire breaks in perimeters adjacent to roads.

  • Muhamed Adem , Adefires Worku , Mulugeta Lemenih , Wubalem Tadesse , Jürgen Pretzsch

    South Omo Administrative Zone in Ethiopia is home to 18 indigenous ethnic groups whose livelihood is vulnerable due to recurrent drought and degradation. Despite the preliminary observation showing the rich dry-forest resource base that, if sustainably managed could enhance livelihoods and biodiversity conservation, there is lack of empirical data on its current status. We conducted a study aiming at quantifying the population status of gum- and resin-bearing species in two randomly selected districts, Hamer and Bena-Tsemay. Seventy-five quadrats (35 at Hamer and 40 at Bena-Tsemay) each measuring 400 m2 were established along line transects to assess species diversity and equitability, density, frequency, dominance, importance value and population structure. We recorded a total of 27 woody species of 12 families and 14 genera. Fifteen species (9 at Hamer and 14 at Bena-Tsemay) of the genera Acacia, Boswellia, Commiphora and Sterculia, were identified as either major sources of commercial gums and resins or their adulterants. Gum- and resin-bearing species comprised 56% and 57% of species richness, 48% and 50% of total density per ha, 95% and 98% of basal area, and 64% and 56% of importance values at Hamer and Bena-Tsemay, respectively. Diversity of the entire woody species assemblage and of the gum- and resin-bearing species was slightly higher at Bena-Tsemay (H= 2.61, 1.4) than at Hamer (H′= 2.48, 1.28), respectively. The diversity and abundance of the resource base suggest potential for development of value-added commercialization of gum and resins to enhance livelihoods and encourage sustainable management of the forest at these study areas. We recorded, however, declining natural regeneration of most gum- and resin-bearing species, and this calls for integrated and participatory species management and landscape rehabilitation.

  • Sheng-nan Shi , Zhan-yuan Yu , Qiong Zhao

    Nitrogen was the main limiting nutrient of net primary production in the southeastern Keerqin Sandy Lands, Northeast China. Species richness declined and biomass increased after five consecutive years of nitrogen fertilization of these sandy grasslands (2004–2008). After fertilization had been stopped for three years (2009–2011), we surveyed vegetation on previously fertilized plots to quantify changes in community composition. Respect species richness showed an increasing trend over time since the cessation of fertilization. Respect vegetation height and coverage showed decreasing trends over time since the cessation of fertilization. Species composition changed after fertilization ceased, the dominant species shifting from Cannabis sativa, Phragmites communis and Chenopodium acuminatum in 2008 to Cannabis sativa, Phragmites communis and Artemisia scoparia in 2011. Dominance of dominant species declined from 66.2% in 2008 to 57.5% in 2011. The importance value of annual plants in the earlier nitrogen addition plots was higher than in control plots, but the differences were not significant in 2011. The importance value of perennial plants differed significantly between treatments from 2009 to 2011. The reversion rate not only differed between community characteristics, but also between functional groups in the same community characteristic. Although the residual effect of nitrogen addition on vegetation was still observed three years after fertilization ceased, the vegetation showed signs of recovery.

  • Sanjay Gairola , R. S. Rawal , N. P. Todaria , Arvind Bhatt

    The population structure of tree species has been explored in order to elucidate regeneration potential of the subalpine forests of Indian western Himalaya. For this study, the subalpine forest area was divided into three strata, i.e., lower altitude (<3000 m); mid-altitude (3000–3200 m); and high altitude (>3200m). Considering the major compositional attributes, an increase in altitude came with a significant decline in tree density and the total basal area for all the sites. However, no such clear trends were observed for recruits (i.e., seedlings and saplings). Seedling density did not exhibit uniform patterns for sites and altitude strata. In general, overall seedling density was greater at the Pindari site compared to the Lata and Tungnath sites. By comparison, significant variation in seedling density along the altitude strata was recorded for the Tungnath and Pindari sites only. Likewise, sapling density patterns varied across the sites and altitude strata, and significant variation in sapling density along the altitude strata was recorded only for the Lata site. At the Pindari site, the continuous increase in sapling density along with increasing altitude was revealing. The Pindari forests of exhibited expanding population structure. In contrast, greater accumulation of individuals in the sapling class and sharp decline toward both higher tree classes and lower seedling classes was generally apparent for the Lata and Tungnath sites. This indicates that the replacement in tree size classes from sapling stage is not proportional and the population may decline in the long-term. Considerable variation in patterns of forest and dominant species population structure were evident across altitude strata. But in all cases irrespective of sites, we found growth at the high-altitude stratum, in the form of entire forests or dominant species. This trend deserves further investigation to explore its relevance under changing climate scenarios.

  • Zhi-liang Zhang , Guo-dong Liu , Fu-cang Zhang , Cai-xia Zheng , Fu-quan Ni , Yin-hong Kang , Yun Zeng

    A pot experiment was conducted to investigate the effects of nitrogen content [N1 (no fertilizer), N2 (0.15 g·kg−1), and N3 (0.3 g·kg−1)] on the growth and the hydraulic characteristics of peach seedlings under different soil moisture conditions (W1, W2 and W3, in which the soil water content was 45% to 55%, 60% to 70%, and 75% to 80% of the field water capacity, respectively) by using a specialized high pressure flow meter with a root chamber and a coupling, which was connected to plant organs. Leaf area and leaf hydraulic conductivity (K L) increased significantly in the seedlings because of increased soil moisture and N content. K L increased with leaf area. A linear correlation was documented between K L and leaf area. K L was higher in the morning and began to decline sharply after 16:00, at which K L declined after an initial increase. Soil moisture and N content enhanced shoot (K s) and root (K r) hydraulic conductivities, thereby improving the low soil moisture condition to a large extent. K s and K r of the seedlings were reduced by 32% and 27% respectively in N1, and by 14.7% and 9.4%, respectively in N2, and both in W1, compared with the control treatment. N3 had no significant effect on K s and K r under similar conditions. Linear negative correlations were observed between K r and the excised root diameter as well as between K s and the shoot stem diameter. The shoot-to-root ratio increased with increase in N content. The shoot-to-root ratio in N3 was increased by 14.37%, compared with N1 in W1 as well as by 12% and 4.39% in W2 and W3, respectively. Knowledge of the effects of soil moisture and N fertilizer on hydraulic characteristics and growth is important. Our results provide basic guidelines for the implementation of water-saving irrigation and fertilization management of nursery stock.

  • Peng-fei Wu , Xiang-qing Ma , Mulualem Tigabu , Yong Huang , Li-li Zhou , Liping Cai , Xiao-long Hou , Per Christer Oden

    Plantations of eucalypts as short-rotation tree crops are rapidly expanding in tropical and sub-tropical regions, including southern China, where the soils are acidic and available phosphorus (P) is limited. We investigated seedling growth, dry matter accumulation, and the dynamics of photosynthetic rate and chlorophyll content of seven Eucalyptus species/hybrids (E. dunnii, E. grandis, E. grandis × E. camaldulensis, E. urophylla × E. camaldulensis, E. urophylla × E. tereticornis, E. grandis × E. tereticornis, E. urophylla × E. grandis) in response to different levels of P supply (0, 6, 12 and 18 mg·kg−1 KH2PO4). The photosynthetic rate and the chlorophyll content significantly declined as the P supply declined in almost a linear fashion for all species as the P stress period extended. In the absence of P supply, height growth of seedlings of all species was significantly impaired, while root collar diameter growth and whole plant dry matter accumulation was not affected by the level of P supply in most of the species. Significant inter-species variations in growth, dry matter accumulation and photosynthetic rate in response to P supply were detected. Eucalyptus dunnii had the lowest growth performance across all levels of P supply while E. Urophylla × E. tereticornis showed superior growth performance. From a practical point of view, E. Urophylla × E. tereticornis is suggested as a candidate hybrid for planting on slightly P-deficient sites in southern China while E. dunnii, being a slow-growing species, is not suitable for short-rotation plantation. On plantation sites where severe P deficiency exists, P fertilization needs to be considered to boost rapid growth of seedlings so as to meet the management objectives of short-rotation plantation.

  • Fousseni Folega , Chun-yu Zhang , Xiu-hai Zhao , Kperkouma Wala , Komlan Batawila , Hua-guo Huang , Marra Dourma , Koffi Akpagana

    Remote-sensing data for protected areas in northern Togo, obtained in three different years (2007, 2000, and 1987), were used to assess and map changes in land cover and land use for this drought prone zone. The normalized difference vegetation index (NDVI) was applied to the images to map changes in vegetation. An unsupervised classification, followed by classes recoding, filtering, identifications, area computing and post-classification process were applied to the composite of the three years of NDVI images. Maximum likelihood classification was applied to the 2007 image (ETM+2007) using a supervised classification process. Seven vegetation classes were defined from training data sets. The seven classes included the following biomes: riparian forest, dry forest, flooded vegetation, wooded savanna, fallows, parkland, and water. For these classes, the overall accuracy and the overall kappa statistic for the classified map were 72.5% and 0.67, respectively. Data analyses indicated a great change in land resources; especially between 1987 and 2000 probably due to the impact of democratization process social, economic, and political disorder from 1990. Wide-scale loss of vegetation occurred during this period. However, areas of vegetation clearing and regrowth were more visible between 2000 and 2007. The main source of confusion in the contingency matrix was due to heterogeneity within certain classes. It could also be due to spectral homogeneity among the classes. This research provides a baseline for future ecological landscape research and for the next management program in the area.

  • Mohammad Redowan , Sharmin Akter , Nusrat Islam

    We mapped the forest cover of Khadimnagar National Park (KNP) of Sylhet Forest Division and estimated forest change over a period of 22 years (1988–2010) using Landsat TM images and other GIS data. Supervised classification and Normalized Difference Vegetation Index (NDVI) image classification approaches were applied to the images to produce three cover classes, viz. dense forest, medium dense forest, and bare land. The change map was produced by differencing classified imageries of 1988 and 2010 as before image and after image, respectively, in ERDAS IMAGINE. Error matrix and kappa statistics were used to assess the accuracy of the produced maps. Overall map accuracies resulting from supervised classification of 1988 and 2010 imageries were 84.6% (Kappa 0.75) and 87.5% (Kappa 0.80), respectively. Forest cover statistics resulting from supervised classification showed that dense forest and bare land declined from 526 ha (67%) to 417 ha (59%) and 105 ha (13%) to 8 ha (1%), respectively, whereas medium dense forest increased from 155 ha (20%) to 317 ha (40%). Forest cover change statistics derived from NDVI classification showed that dense forest declined from 525 ha (67%) to 421 ha (54%) while medium dense forest increased from 253 ha (32%) to 356 ha (45%). Both supervised and NDVI classification approaches showed similar trends of forest change, i.e. decrease of dense forest and increase of medium dense forest, which indicates dense forest has been converted to medium dense forest. Area of bare land was unchanged. Illicit felling, encroachment, and settlement near forests caused the dense forest decline while short and long rotation plantations raised in various years caused the increase in area of medium dense forest. Protective measures should be undertaken to check further degradation of forest at KNP.

  • Darryl. E. Carlyle-Moses , Chad. E. Lishman , Adam. J. McKee

    Rainfall, throughfall and stemflow were measured and canopy interception loss was derived for 14 rainfall events from June 22 to August 30, 2008 within a mature declining hybrid white spruce (Picea glauca (Moench) Voss × P. engelmannii Parry ex Engelm.)-subalpine fir (Abies lasiocarpa (Hook.) Nutt.)-lodgepole pine (Pinus contorta var. latifolia Dougl. ex Loud.) stand in south-central British Columbia, Canada. Stemflow was negligible during the study period, while, respectively, throughfall and canopy interception loss accounted for approximately 59.4% and 40.6% of the 50.1 mm of cumulative rainfall. Throughfall variability was assessed with three approaches involving roving and stationary wedge-type gauges, and stationary trough gauges. Throughfall exhibited large spatial variability with the coefficient of variability of study period throughfall sampled using 16 stationary trough gauges being 30.3%, while it was 38.0% and 28.7% for 32 stationary and 32 roving wedge gauges, respectively. Our analysis suggests that a roving gauge method is better than a stationary approach since the errors associated with event mean throughfalls are summed quadratically and a greater portion of the canopy area is sampled. Trough gauges were more efficient than wedge gauges; however, this efficiency was less than expected given their much larger sampling areas, suggesting that spatial autocorrelation lengths of throughfall may be longer than the trough systems. The spatial distribution of throughfall showed a high degree of temporal persistence throughout the study suggesting the existence of stable “wet” and “dry” inputs to the floors of these coniferous forests.

  • Yogeshwar Mishra , Rimi Rawat , P. K. Rana , M. K. Sonkar , Naseer Mohammad

    We investigated the effect of seed mass on emergence, seedling survival and growth of Pterocarpus marsupium Roxb., a medium to large, commercially valuable and deciduous tree species. Among the three size classes viz. small (10–12 mm), medium (13–15 mm) and large (16–17 mm), the maximum proportion of seed by number (54.12%) and dry weight (51.87%) was recorded in the medium size seed class. Seed length and seed width were greatest in the large seed class (16.50 mm, 7.33 mm) followed by medium (13.50 mm, 5.60 mm) and small (11.37 mm, 3.66 mm). Similarly, hundred seed weight (100 sw) varied from a maximum of 12.92 g in the large seed class to intermediate 10.95 g in the medium seed class and minimum of 7.02 g in the small seed class. The large seed size showed maximum emergence and shoot length over the medium and small seed class. After six months of growth, significant variations due to seed size were also observed for the growth and dry weight of P. marsupium seedlings. Seedling vigour, expressed in terms of height, collar diameter, number of leaves and dry biomass, was significantly affected by seed class. Seedlings that emerged from large seeds showed better growth and produced heavier seedlings as compared to medium and small seeds.

  • Md. Jahirul Islam , Tapan Kumar Nath

    An exploratory survey was conducted among the Khasia living in Lawachara National Parkt (LNP) to investigate their dependency on the protected area (PA) for livelihoods, betel leaf hill farming, traditional forest conservation and perceptions of the PA. Field data were collected by interviewing 48 household heads from two villages (punjis) located inside the LNP and visiting their farms. The economy of the Khasia was forest-based. They were largely dependent on betel leaf hill farming in LNP and nearly 71% of their mean annual income was derived from this irrespective of farmer category. On average, about 14% of the incomes of the poorer farmers came from forest produce followed by 10% and 6% for medium and rich farmers respectively. Hills and forests were the foundations of their lives and livelihoods, and LNP was the life-blood of Khasia survival. As a sustainable production system, this farming practice plays a vital role in conserving biodiversity in LNP and might be replicated elsewhere.

  • Soleiman Mohammadi Limaei , Maryam Seddigh Kouhi , Teymour Rostami Sharaji

    We used a goal programming technique to determine the optimal harvest volume for the Iranian Caspian forest. We collected data including volume, growth, wood price at forest roadside, and variable harvesting costs. The allometric method was used to quantify sequestrated carbon. Regression analysis was used to derive growth models. Expected mean price was estimated using wood price and variable harvesting costs. Questionnaire was used to determine the constraints and the equation coefficients of the goal programming model. The optimal volume was determined using the goal programming method according to multipurpose forest management. LINGO software was used for analysis. Results indicated that the optimum volumes of species were 250.25 m3·ha−1 for beech, 59 m3·ha−1 for hornbeam, 73 m3·ha−1 for oak, 41 m3·ha−1 for alder, and 32 m3·ha−1 for other species. The total optimum volume is 455.25 m3·ha−1.

  • A. K. Hegazy , A. A. Alatar , J. Thomas , M. Faisal , A. H. Alfarhan , K. Krzywinski

    This study presents a survey of wild plants commonly used by local inhabitants in the highlands of southwest Saudi Arabia. Based upon literature review, direct observation of local inhabitants, and questionnaire interviews, 36 plant species were assessed and given scores according to their use. The gaps between scientific and indigenous knowledge on the use of plants were estimated using a “compatibility ratio”. The score values were estimated based on seven different use categories of ecosystem services, including food, forage, medicine, wood, beekeeping, research, and education. Additional structural categories include source of materials, shade, hedges, ornamental plantings, and soil stabilization. There are discrepancies between indigenous knowledge (IK) and scientific knowledge (SK) but in most cases, SK of the species supports the IK and plant users preference. The results also provide information that challenges assumptions about the consistency of IK with SK. Our study highlights the importance of understanding the cultural context and uses of wild plants. Biodiversity-based knowledge holds promise for contributing to sustainable use of wild plant resources and related traditions. The success of such endeavours depends on the compatibility and complementarity of indigenous and scientific knowledge.

  • Tinsae Bahru , Zemede Asfaw , Sebsebe Demissew

    We undertook ethnobotanical study of forage/fodder plant species used by the Afar and Oromo (Kereyu and Ittu) Nations in and around the semi-arid Awash National Park (ANP), Ethiopia. The study aimed at investigating and documenting indigenous knowledge (IK) on forage/fodder plant species and threats to their survival. Ninety-six informants between 20 and 80 years old were selected using prior information. Data were collected using semi-structured interview, guided field walk, discussion and field observation. Preference ranking, Jaccard’s coefficient of similarity and priority ranking were used for data analysis. One hundred twenty-six forage/fodder species of 90 genera and 43 families were collected in the study area. More than 88% of the species were reported with their vernacular names, where 68% were reported by the Afar Nation and 70% by the Oromo Nation. Family Poaceae was represented by 25 species (20%), followed by Fabaceae 18 (14%). Preference ranking for the most preferred forage grasses as perceived by key informants revealed that Chrysopogon plumulosus was the most important forage/fodder species. Overgrazing was the major threat in the study area, scoring 22%.

  • Side Sadat Ebrahimi , Hassan Pourbabaei , David Potheir , Ali Omidi , Javad Torkaman

    Plant diversity plays key ecological roles in forest ecosystems, including influencing succession, resilience and nutrient cycling. This study was conducted to investigate the effect of livestock grazing and human uses on herbaceous species diversity. We surveyed 50 ha of protected area and 50 ha of unprotected area to evaluate herbaceous species diversity in oriental beech (Fagus orientalis Lipsky) forests in northern Iran. We calculated and compared three indices each of diversity and evenness, and species richness between the two areas. Herbaceous cover was higher in the unprotected area while leaf litter depth and tree canopy cover were higher in the protected area. The diversity indices, H (Shannon-Wiener index), N1 (McArthur index), N2 (Hill’s index), EQ (Modified Nee index), Evar (Smith-Wilson index), E5 (modified index of Hill) and R=S (species richness) and species richness R=S were greater in the protected area than in the unprotected area, suggesting that protection from grazing results in increased numbers of plants and species. The effect of land protection on plant diversity was more pronounced for evenness than for species richness and the positive correlation between diversity and evenness indices was higher than that between diversity and richness.

  • Shovan Dattagupta , Abhik Gupta , Manoranjan Ghose

    We identified 67 and 21 NTFP-yielding plant and animal species, respectively, in a reserve forest in Cachar district of Assam. We recorded globally threatened species listed by IUCN as Critically Endangered (plant species Dipterocarpus turbinatus), Vulnerable (plant species Aquillaria malaccensis), Endangered (animal species Hoolock hoolock, Indotestudo elongata and Manis pentadactyla), and Vulnerable (animal species Nilssonia hurum and Rusa unicolor). The whole plant or animal and/or their various parts were used as food or medicine, in house construction, magico-religious activities and others. While some NTFPs were harvested throughout the year, others were harvested seasonally. A comprehensive NTFP policy, along with scientific measures for regeneration, restoration and augmentation of NTFP-yielding plants and animals, would help in addressing the conflicting demands of conservation and livelihood in the forests of this area.

  • Ritesh Kumar , N. Chandrashekar

    We investigated the fuel characteristics of five important bamboo species viz., Dendrocalamus strictus, D. brandisii, D. stocksii, Bambusa bambos and B. balcooa. The selected species cover more than 85% of the total growing stock of bamboo in India. Basic density varied from 0.48 to 0.78 g·cm−3 among the bamboo species studied. Ash content, volatile matter content and fixed carbon content ranged between 1.4%–3.0%, 77.2%–80.8% and 17.6%–21.1%, respectively. Variation in calorific value (18.7–19.6 MJ·kg−1) was marginal. Fuel value index varied widely (586–2120) among bamboo species. The highest calorific value (19.6 MJ·kg−1) and fuel value index (2120) were found in B. balcooa. Ash elemental analysis revealed that silica and potassium are the major ash forming minerals in bamboo biomass. Silica content ranged from 8.7% to 49.0%, while potassium ranged from 20.6% to 69.8%. We studied combustion characteristics under oxidizing atmosphere. Burning profiles of the samples were derived by applying the derivative thermogravimetric technique which is discussed in detail. The five bamboo species were different in their combustion behaviour, mainly due to differences in physical and chemical properties. We compare fuel properties, ash elemental analysis and combustion characteristics of bamboo biomass with wood biomass of Eucalyptus hybrid (Eucalyptus tereticornis × Eucalyptus camaldulensis).

  • Mohammad Derikvand , Ghanbar Ebrahimi

    We determined the effects of adhesive type and loose tenon dimensions (length and thickness) on bending strength of T-shaped mortise and loose-tenon joints. Polyvinyl acetate (PVAc) and two-component polyurethane (PU) adhesives were used to construct joint specimens. The bending moment capacity of joints increased significantly with increased length and thickness of the loose tenon. Bending moment capacity of joints constructed with PU adhesive was approximately 13% higher than for joints constructed with PVAc adhesive. We developed a predictive equation as a function of adhesive type and loose tenon dimensions to estimate the strength of the joints constructed of oriental beech (Fagus orientalis L.) under uniaxial bending load.

  • Mohsen Javanmiri Pour , Mousa Rasouli , Hamid Soofi Mariv , Mohammad Avatefi Hemat , Masood Shahmoradi