Alka Kumari , K. P. Tripathi

Abstract

The study site was thermal power station, Kanti and nearby locality (District Muzaffarpur, Bihar), having Gangetic plain topography with fertile soil. But fly ash deposition of thermal power has reduced the soil fertility of nearby area and consequently local farmers were vexed by adverse effect on crop yield. In similar condition ferns were found luxuriantly growing inside and outside the campus of thermal power without any visible phytotoxic symptoms. In context of the above, during present study metal content and physico-chemical properties of the fly ash site and soil samples of natural forest site of Balmikinagar (reference site) were studied. Community structure (frequency, density, abundance, and IVI) and several diversity indices including population density, concentration of dominance, heterogeneity, equitability, Shannon Wiener's diversity index of ferns of both fly ash site and reference site were studied. Effect of fly ash on photosynthetic pigments were studied and compared with reference site. Results showed that fern communities existing on fly ash site perform better than reference site even in presence of high metal content in fly ash. As ferns grown on fly ash site show slight reduction in chlorophyll content but no visible toxicity symptoms and have higher population distribution, it indicates the possibility of management of metal loaded wastelands with metal accumulator fern species.

Keywords

Fly Ash, Ferns, Diversity Indices, Management

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Bajrang Singh , K. P. Tripathi

Abstract

Monthly variation in nutrient concentrations of leaf and current twigs was observed in 5-yearold Populus deltoides trees planted at Lucknow. Leaves appeared to be more sensitive indicator for all nutrient elements consisting of a relatively high concentration in comparison to twigs. The magnitude of nutrient status was in the order of N > Ca > K > Mg > Na > P> Fe. The levels of N, P and K decreased in the different ways as the season's growth proceeds. In contrast, the concentrations of Ca and Mg increased slightly with fluctuations expressing a polynomial order with the advancement in growing season. Na concentration increased to some extent whereas Fe decreased during the life span of the leaves on the trees from May to December. Nutrient concentration in the twigs remained almost stable except P and Fe, which varied according to foliage concentrations following similar trend during annual cycle. The appropriate time of the sampling was identified in August for the diagnosis of the nutrient status of the stand when all the essential elements remained fairly stable during the season's growth of the plants. Maximum retranslocation was recorded for N (60%), whereas minimum for Mg content (9%) at the termination of growing season.

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Bajrang Singh , V. K. Garg , P. K. Singh , K. P. Tripathi

Abstract

New forests created on sodic wastelands, consisting of different community structure ameliorate the soil at various degrees according to productivity and diversity status. Three such forested sites were selected at Banthra Research Station of National Botanical Research Institute, Lucknow, India with different productivity and diversity indices descending from site I (S₁) to III (S₃), which were compared with a control (non forested) sodic soil site. Importance value index (IVI) decreased from 320 to 150 from site I to III. Shannon-Wiener's general diversity index was greatest in site I (1.85) and lowest in site III (1.37). Population density, basal area and biomass also declined accordingly. Dominant genera in these Forest stands were Acacia, Albizia, Dalbergia, Terminalia, Bauhinia and Syzygium whereas grasses/forbs viz.Sporobolus, Desmostachya and Dactyloctenium were common on barren sodic land. A remarkable reduction in soil pH and exchangeable sodium percentage (67-73%) was noticed in afforested sites compared to the control as a result of combined effect of increased diversity and productivity. Individual effects of diversity or productivity were measured as 42% and 58%, respectively in soil amelioration. The soil fertility increased 2 to 3 times in organic carbon and 2.7 to 3.7 times in total nitrogen content on afforested sites. However, these improvements were greatest in surface soil (0.15 m) for C and N (68 & 73%) in comparison to lower depths (51 & 65%). Among the exchangeable cations, Na⁺ reduced by 41-57% from the control in afforested sites (I and II) while Ca⁺⁺ content increased of 38-68% in these sites. In general, available Zn, Fe and Mn contents increased in forested sites I and II whereas Cu decreased significantly in site II but remains at par on site I from the control. A rapid ch!lnge in soil properties occurred on surface soil even on poor afforested site while the rate of improvement at depths below 0.3 m depicted a slow amelioration process. A combined effect of both biomass productivity and species diversity of about 92% ameliorated the soil more significantly instead of individual factors, which should be taken into account for the rehabilitation of such sodic soil sites.

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K. P. Tripathi , Shanta Mehrotra , P. Pushpangadan

Abstract

In a vegetation study conducted in coastal and inland sites of North, Middle and South Andaman tropical forests, a total of 49 species belonging to 27 families were found. Species like Bruguiera gymnorrhiza, Ceriops tagal, Heritiera littoralis, Morinda citrifolia, Rhizophora apiculata, and R. mucronata were common in coastal forest, whereas Ficus hispida, Lagerstroemia hypoleuca and Pterocarpus dalbergioides were common in inland forests. The population density ranged from 195 (Middle Andaman; inland forest) to 822 plants ha^-1 (North Andaman; coastal forest) with their basal area from 12.44m² ha^-1 (South Andaman; inland forest) to 77.4m² ha^-1 (North Andaman; coastal forest). Inland forests (South Andaman) were found to have higher species diversity. The Shannon Wiener's diversity index ranged from 2.26 (South Andaman; coastal forest) to 3.04 (South Andaman; inland forest). Mean girth showed highest value (104.34cm) for inland forests (North Andaman). Size variation was greatest in inland forest of South Andaman showing the highest degree of asymmetry.

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K. P. Tripathi , Bajrang Singh

Abstract

A semi-natural forest developed on sodic wasteland during the last 40 years at Banthra Research Station of National Botanical Research Institute, Lucknow, was characterized as mixed dry subtropical forest with deciduous and evergreen species. The forest constituted about 74 species belonging to 35 families. These were classified in overstory (44), understory (19), ground layer (8) and climber (3). Several species of overstory were also found in understory and ground layer vegetation, which indicated the regeneration potential of a few species. In overstory vegetation Syzygium cumini, Bauhinia variegata, in understory Leucaena leucocephala, Barleria prionitis and in ground layer Clerodendrum vescosum had greatest abundance. The forest constituted about 30 m² ha^-1 basal area predominantly occupied by overstory trees. Three stands (S1, S2, S3) were selected on the basis of gross morphology. In S1 stand Bauhinia variegata and Albizia lebbek were most dominant species on the basis on IVI (41) and basal area (4.35 m² ha^-1), Leucaena leucocephala was the dominant species of understory on the basis of IVI (98). Barleria prionitis and Leucus biflora were dominating in ground layer with basal cover 1.94 and 0.7 m² ha^-1, and IVI 44, and 84. In S2 stand, Bauhinia variegata dominated with greatest IVI (65) in overstory vegetation, whereas Syzygium heyneanum had greatest basal area (6.6 m² ha^-1) with 64 IVI and it was also dominated in understory vegetation with maximum IVI (51). Barleria prionitis (IVI 124, basal cover 113.4 m² ha^-1) and Clerodendrum vescosum (IVI 74, basal cover 108.4 m² ha^-1) were dominated in ground layer vegetation. In S3 stand Syzygium heyneanum were dominated in overstory and understory vegetation on the basis of IVI (60 and 51), but Albizia lebbek had greatest basal area (6.4 m² ha^-1) in overstory. Syzygium heyneanum also dominated in understory vegetation while Pedilanthus tithymaloides was most common in ground layer vegetation. Syzygium heyneanum had greatest population density (159 plant/ha) for overstory and 524 plant/ha for understory vegetation while in ground layer vegetation Clerodendrum vescosum was the most abundant species with 780 plants/ha.

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K. P. Tripathi , Bajrang Singh

Abstract

A forest ecosystem was developed on barren sodic land at Bantbra Research Station of National Botanical Research Institute, Lucknow, India during 1960s. About 74 species belonging to 34 families were recorded in this new forest, which was characterized as mixed dry sub-tropical forest with deciduous and evergreen species. The forest was classified into overstory, understory and ground layer vegetation based on the morphological variation and vertical strata of the vegetation. Frequency, density, abundance and basal area were evaluated for each species and dominants were assorted on the basis of basal area and Importance Value Index. Shannon Wiener's diversity index measured as 3.6, 3.3, and 1.8 for overstory, understory and ground layer vegetation, respectively. Forest biomass (dry weight) was estimated to be 347 Mg ha^-1 with a net primary production of25 Mg ha^-1 yr^-1 at the age of 40 years. Forest sequestered about 168 Mg ha^-1 carbon content in their standing biomass with current accumulation rate of 11 Mg ha^-1 yr^-1 and conserved 8.9 TJ ha^-1 energy in their standing stock. Annual energy fixation was estimated to 644 GJ ha^-1. Nutrient pool and fluxes in the forest were also determined. Further, the role of litter and fine ischolar_mains in reclamation of sodic soil was quantified.

Keywords

Reclamation, Ecorestoration, Diversity Index, Importance Value Index, Nutrient Content And Soil Amelioration.

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