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1.
J Environ Biol ; 33(2): 215-21, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23033683

RESUMO

Wood elements and anatomical ratio of Dipterocarpus indicus were studied to evaluate variation among populations and to recommend for end selection. The variation of wood element [fibre length (FL), fibre diameter (FD), lumen diameter (LD), cell wall thickness (CWT), double wall thickness (DWT), and lumen volume (LV)] and anatomical ratio [fibre lumen area (FLA), slenderness ratio (SR) and runkel ratio (RR)] were investigated in a girth class of 100 - 120 cm among eight populations of Dipterocarpus indicus in Western Ghats, India. The study revealed a significant variations in FL (0.2426), FD (4.7019), LD (3.1689), CWT (2.7104), DWT and (5.4298) among populations. The variations in anatomical ratios were significant among populations except in case of LV. The causes of variations among populations in their wood traits were attributed to the site factors. The interaction between genetic makeup of wood traits combined with effects of edaphic, local and regional climatic conditions reflect the amount of variation among populations. The highest coefficient of variation (CV %) for FL, FD, CWT and DWT was recorded in population of Gundya whereas low coefficient of variation were recorded in the population of Makuta (FL), Devimane (FD, CWT and DWT), and Sampaje (LD). The wood of Dipterocarpus indicus was found undesirable for pulp wood but can be utilized for plywood timbers.


Assuntos
Dipterocarpaceae/classificação , Dipterocarpaceae/fisiologia , Madeira/fisiologia , Índia
2.
J Environ Biol ; 33(4): 791-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23360009

RESUMO

The research was focused on exploring the structure, diversity and form of regeneration process of the Dipterocarp forests in Western Ghats in relation to environmental factors. Eight populations in the distribution range of Dipterocarp forests were selected. In each population 32 plots of 2mx2m were laid down randomly. Atotal of 1243 seedlings < or = 10 cm dbh (diameter at breast height) belonging to 99 species and 48 families were recorded. The number of regenerated tree species was found to be high in the populations of Mudigere (40), Sakleshpura (40) and Makuta (39), which are characterized by favorable locality factors and lower disturbances. The highest similarity index in species composition was recorded between the populations of Sampaje in Kodagu district and Gundya in Dakshina Kannada (60%) whereas the lowest similarity index was observed between the population of Sringeri in Chikmagalore and Sampaje (53%) and Gundya and Makuta (35%) in Kodagu district. Dipterocarpus indicus was found to be dominant among the regenerated tree species in all the sites studied except Gundy and Sampaje. The frequencies of regeneration classes (seedlings, saplings, poles and adult trees) were shaped as inverse J curve indicating the normal regeneration pattern under the present disturbance. The average disturbance of litter collection, grazing, fire, weeds and canopy opening were significant among different populations (p < or = 0.05). Negative correlation was observed between disturbance and species richness, number of individuals and density.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Árvores/classificação , Índia
3.
J Environ Biol ; 30(5): 713-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20136054

RESUMO

The paper highlights the fish diversity in major wetlands of Mysore district, Karnataka, India and its conservation status. Forty-five species of fishes belonging to 15 families, 31 genera have been identified. Fish species belonging to genus Puntius were more common in many of these lakes. However it was observed that the fish diversity was decreasing since last two years unprecedently mainly due to manifold human activities. Fish diversity in the lakes is becoming rare and about seven species were identified as endangered. Out of the 45 identified fishes, six fish species were identified as threatened species. Tork hudree, also known as Deccan mahseer and seven other species were identified as vulnerable fish species. Though there were 40 species of fish endemic to this region, their number decreased with introduction of more exotic species. Conservation of endemic fishes, propagation of endangered and threatened fishes should be therefore, undertaken to preserve and protect fish diversity in the wetlands of Mysore district.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Peixes/fisiologia , Áreas Alagadas , Animais , Índia , Densidade Demográfica , Dinâmica Populacional
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