2025-04-08 2011, Volume 22 Issue 4

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  • R. K. Vashistha , Neelam Rawat , A. K. Chaturvedi , B. P. Nautiyal , P. Prasad , M. C. Nautiyal

    The present study was conducted in the alpine pastures of Tungnath (30° 14′ N and 79° 13′ E) to observe life-form and growth-form patterns of alpine plant species under grazed and ungrazed conditions and to work out the plant life form spectrum. Species were categorized as plant habit, height and length of growth-cycle and life-form classes according to Raunkiaer’s system. The results show that in total of 68 species at grazed site, hemicryptophytes (He) accounted for 50.00% species, followed by cryptophytes (26.47%), chamaephytes (16.18%), phanerophytes (4.41%) and therophytes (2.94%). At the ungrazed site in 65 plant species, hemicryptophytes (He) accounted for 49.23% species, cryptophytes (26.15%), chamaephytes (15.38%), phanerophytes (6.15%) and therophytes (3.08 % species). In general, hemicrptophyte are dominant in both sites i.e. graged and ungrazed. Growth form categories were classified as forbs, shrubs, grasses and sedges and undershrubs, according to plant habit and height. On the basis of length of the growth cycle, species were categorized as plant species of short growth cycle, intermediate growth cycle and long growth cycle. The short forbs of plant habit and height, had the highest emergence, and grasses and sedges had the lowest emergence in representative species. Percentage of species with long growth cycle was highest in both sites.

  • H. S. Ginwal , S. S. Maurya , P. Chauhan

    Random Amplified Polymorphic DNA (RAPD) polymorphism was employed to assess the genetic diversity in the elite germplasm of Dalbergia sissoo. Sixty-seven clones that are under cultivation in northern India, originated from six different states of India and Nepal were analyzed with 30 RAPD primers that generated a total of 342 fragments out of which 290 were polymorphic. Total genetic diversity (Ht) varied between 0.01 and 0.37, with an average of 0.19. Shannon’s Information index (I) varied between 0.02 and 0.54, with an average of 0.31. Marker attributes like Polymorphism Information Content (PIC), Marker Index (MI) and Effective Multiplex Ratio (EMR) values were calculated to assess the discriminatory power of 30 primers used. The PIC values ranged from 0.01 to 0.37 with an average of 0.17 per primer and the EMR ranged from 0.17 to 21.00 with a mean of 8.66 across all genotypes. Closely related clones were C49 and C51 with similarity index of 0.86 while the least similar or most dissimilar clones were C14 and S-DB showing similarity index of 0.58. The UPGMA-phenogram categorized the 67 clones into six clusters based on genetic similarity and dissimilarity. The clustering of clones in relation to their geographical location has been discussed.

  • Kumud Dubey , K. P. Dubey

    The Shankargarh forest area is rich in silica, a major mineral used in glass industry. Extensive open cast silica mining has severely damaged the forest as well as productivity of the region. An understanding of the impact of mining on the environment particularly on vegetation characteristics is a prerequisite for further management of these mining sites, especially in the selection of species for reclamation works. The present paper deals with the study of the tree composition of silica mining area of Shgankargarh forest, at both disturbed and undisturbed sites. Tree vegetation study was conducted at undisturbed and disturbed sites of Shankargarh forests using standard quadrate method. Density, abundance and frequency values of tree species were calculated. Species were categorized into different classes according to their frequency. The importance value index (IVI) for each species was determined. Species diversity, Concentration of dominance, Species richness and Evenness index were calculated for the undisturbed and disturbed sites. The distribution pattern of the species was studied by using Whitford’s index. Similarity index between tree composition of disturbed and undisturbed sites was determined by using Jaccard’s and Sorenson’s index of similarity. Tree species showed a drastic reduction in their numbers in disturbed sites compared to that of the undisturbed sites. The phytosociological indices also illustrated the impact of mining on the tree composition of the area. The present study led to the conclusion that resultant tree vegetation analysis can be used as important tool for predicting the suitability of particular species for revegetating the mined areas.

  • Subhash Hathurusingha , Nanjappa Ashwath , Kolitha Wijesekara , David Midmore

    Reproductive phenology of multiple use native plant Calophyllum inophyllum L. was studied in Yeppoon (23°7′60″ S, 150°43′60″ E), northern Australia (southern hemisphere) and in Meegoda (6°18′51″N, 80°31′3″), Sri Lanka (northern hemisphere). C. inophyllum trees in Yeppoon, Australia had relatively shorter flowering periods, shorter floral life spans, longer fruit life spans, smaller flowers and larger fruits compared to those in Meegoda, Sri Lanka. Although the number of flower buds/inflorescence was comparatively higher in Meegoda, C. inophyllum trees in both locations had similar mean number of mature fruits/cluster due to the higher floral abscission in C. inophyllum trees at Meegoda. Despite having a comparatively lower fruit yield (664 000 fruts·ha·a), C. inophyllum trees in Yeppoon had higher kernel weights (2 988.0±853.2 kg·ha−1·a−1) and oil yields (1 332.6±380.5 kg·ha−1·a−1) compared to those in Meegoda.

  • Susana Aguilar , Cristina Montiel

    This paper discusses participatory processes in wildland fire management (WFM). Participation is an essential element of both the European Sustainable Development (SD) Strategy and the White Paper on Governance. Governance and SD have thus become an interconnected challenge to be applied to WFM (as a sub-area in forest policy), amongst other policies. An overspread weakness in WFM is lack of real participation of stakeholders. Absence of (or deficient) participation can seriously impair contribution of this group to WFM in high-risk areas and runs counter governance and the SDS. Further, this weakness might prevent an efficient use of fire as a land management tool (prescribed burning, PB) and as a technique for fighting wildfire (suppression fire, SF). Even though these fire practices have been well known in many different places, they have been increasingly neglected or prohibited over time in Southern Europe. At present, forest and fire fighting administrations are turning their eyes back on them and analyzing the benefits of using fire in relation to preventive and suppressive actions. Therefore, participatory and diffusion mechanisms (the latter adopting the shape of national and international experts’ networks) are required in order to solve the socalled fire paradox: that is, the need to move from a one-dimensional perception of the negative impacts of fire to a more sophisticated one that also stresses its positive effects. Governance, based on broad social participation, and diffusion, through fire networks, are of utmost importance in order, first, to diminish long-standing suspicion amongst different interests as to the use of fire and, secondly, to diffuse best practices associated with PB and SF. Most importantly, the EU should exercise its environmental leadership so that these new fire practices and sustainable WFM are diffused across the international arena.

  • Mohammad Arabi , Mehdi Faezipour , Heydar Gholizadeh

    Density and resin content are two factors that have a significant effect on the production cost of wood composite. However, particle size affects resin content and density, which suggests that the interaction of these three factors can be manipulated to reduce the board density and resin content of particleboard without adversely influencing its mechanical properties. Some mathematical functional forms based on resin content, board density and slenderness ratio were regressed and an appropriate form was chosen. According to analysis of the results using SHAZAM 9 software, the exponential function best fit the experimental data. Finally, “indifference curves” of mechanical properties were illustrated and analyzed. The results indicated that negative effects of density or resin content reduction on mechanical properties could be compensated for by controlling particles’ slenderness ratio. Interestingly, increases in slenderness ratio compensated for the negative effects of decreases in resin content or board density on module of rupture (MOR) and module of elasticity (MOE). Moreover, this “compensation ratio” intensified as resin content or density decreased and/or as the MOR or MOE increased. On the other hand, reduction in slenderness ratio indicated a complementary effect on reducing internal bond (IB) strength, a result of decreases in resin content or density. Moreover, this “complementary ratio” was intensified as resin content or density decreased and/or as IB strength increased.

  • Rostam Mousavi , Mehrdad Nikouy , Jori Uusitalo

    An empirical time study was conducted to evaluate the performance of the current felling and tree processing methods used in Northern Iran’s Hyrcanian forest. Motor-manual felling is done mostly in winter, while tree processing starts when the felling season ends. We identified the elements of felling and processing work phases, and 142 cycles and 110 cycles were respectively recorded for felling and processing. On the basis of data analysis (time study), we developed statistical models of effective time consumption in the respective work phase and for its total productivity. The production rate of felling with and without delay time was 9.7 and 11.65 trees per hour (0.17 USD·m−3 and 0.21 USD·m−3), and the average production cost with and without delay was 1.21 USD and 1.45 USD per tree, respectively. The average productivity of processing was 35 m3 per effective hour and the average unit cost of processing was 0.22 USD·m−3.

  • Phan Sy Hieu , Steve Harrison

    This paper reviews alternative market equilibrium models for policy analysis. The origin of spatial equilibrium models and their application to wood and wood-processing industries are described. Three mathematical programming models commonly applied to solve spatial problems — namely linear programming, non-linear programming and mixed complementary programming — are reviewed in terms of forms of objective functions and constraint equalities and inequalities. These programming are illustrated with numerical examples. Linear programming is only applied in transportation problems to solve quantities transported between regions when quantities supplied and demanded in each region are already known. It is argued that linear programming can be applied in broader context to transportation problems where supply and demand quantities are unknown and are linear. In this context, linear programming is seen as a more convenient method for modelers because it has a simpler objective function and does not require as strict conditions, for instance the equal numbers of variables and equations required in mixed complementary programming. Finally, some critical insights are provided on the interpretation of optimal solutions generated by solving spatial equilibrium models.

  • Rong-sheng Li , Guang-tian Yin , Jin-chang Yang , Wen-tao Zou , Jian-guang Li , Shuai Zhang , Rui-feng Jia , Liang Kou , Dong-guang Wang

    Many stems are subject to shoot drying in the plantations of Calamus simplicifolius Wei at the Nanmeiling Base of the Forestry Bureau of Baisha County, Hainan Province. As a palm, stems of C. simplicifolius stop growing and later die if the shoots are dry. Generally, shoot drying means reduced cane production and reduced profit for a rattan plantation. We aimed to quantify the incidence of shoot drying and determine its reason. We sampled eight 20 m × 20 m plots in the C. simplicifolius plantations. In each plot, we counted stems and categorized them as drying shoot or normal shoot, and mother stem or sucker stem. We measured stem length and categorized them as drying shoot and normal shoot for mother stems. We cut open each shoot-drying stem to determine the cause of drying from drying part to fresh part. The frequency of mother stems (259 stem·ha−1), was significantly lower than sucker stems (588 stem·ha−1). The percentage of shoot drying was 33.8% for mother stems, not significantly higher than that for sucker stems (18.9%). The mother shoot stems were significantly shorter if they were drying than if normal. 80% of stems with a drying shoot were hollow within the leaf sheath, whereas 10% hosted lively mature larvae (one larvae per shoot) and 10% hosted several lively young larvae. Mature larvae were identified as the Red Palm Weevil, Rhynchophorus ferrugineus Oliver. To confirm the present of the weevil, three pheromone traps for the weevil were set up in the plantations and adult weevils were trapped on the next day and identified as the Red Palm Weevil. We conclude that shoot drying of C. simplicifolius is probably caused by the Red Palm Weevil.

  • Idris Musa Adam , Kamal E. M. Fadl

    Acacia senegal, the gum arabic producing tree, is the most important tree species for the livelihood of the people in South Kordofan State, Sudan. The objective of this study was to determine the optimum tapping date for gum arabic production in the study area. A randomized complete block design experiment with three replications was conducted at (Meari) area for two continuous growing seasons 2008/2009–2009/2010. The treatments comprised six tapping dates (1 Oct, 15 Oct, 1 Nov, 15 Nov, 1 Dec, and 15 Dec). Results showed highly significant differences (p < 0.001) in gum arabic yield (g√ee) in all pickings and in the total gum yield between the tapping dates. The results also showed that tapping of trees on 15 October and 1 November gave a higher yield compared to the other dates. The highest gum yield of 1086.6 and 661.2 g/tree was recorded on 15 October and 15 November, while the lowest gum yield of 297.9 g/tree was recorded when the trees were tapped on 1 October. The two highest-yield dates of tapping (15 Oct and 1 Nov) are recommended as the best time for tapping for gum arabic production in South Kordofan State. These results can be used to increase gum arabic production and farmer income in South Kordofan State.

  • Alireza Moshki , Norbert P. Lamersdorf

    We conducted a greenhouse experiment to investigate the role of seed source in growth and symbiotic nitrogen fixation of black locust (Robinia pseudoacacia L). Seeds from different sources were planted in the same environmental conditions and inoculated with a suspension of mixed Rhizobium. We used the modified 15N isotope dilution method to estimate biological nitrogen fixation of Robinia trees. Different Robinia seed sources differed significantly in terms of tissue dry weight (50.6–80.1 g), total N (1.31–2.16 g) and proportion of nitrogen derived from the atmosphere (0–51%). A higher nitrogen fixation rate of Robinia trees was associated with higher dry weight. Moreover, the leaves of Robinia proved to adequately represent the nitrogen fixation capacity of entire plants. Our results confirmed that assessment of seed sources is a useful way to improve the nitrogen fixation capacity and therefore the growth rate of Robinia.

  • S. Singh , S. Yadav , P. K. Patel , S. A. Ansari

    The influence of seasonal variation, indole-3-butyric acid (IBA) and type of cuttings was examined on induction and growth of adventitious roots in Bambusa nutans Wall. and Bambusa tulda Roxb. Singlenode culm and culm-branch cuttings from the mature culms were provided with immersion treatment for 24 h of either water (control) or 2 mM IBA in four different seasons, i.e., spring (mid February), summer (mid May), rainy (mid July), and winter (mid November) and maintained for two months in the mist chamber at the relative humidity of (70±5)% and the temperature of (30±2)°C. In B. nutans, adventitious rooting occurred in both types of cuttings in all the seasons with the best rooting in the summer season i.e., May (88% in culm cuttings) and the least in winter. On the contrary, adventitious rooting was recorded only in culm cuttings in spring and summer season in B. tulda. IBA treatment significantly enhanced rooting, root number and root length; registering 14 to 17 times improvement over control in the best rooting season. Three factor-interactions (season × cutting type × IBA treatment) were significant for rooting in B. nutans and all characteristics, except sprouting in B. tulda. Thus, single-node culm and culm-branch cuttings in B. nutans and culm cuttings in B. tulda treated with 2 mM IBA during spring (February) to summer (May) season are recommended for their clonal multiplication.