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621.
Gopal S. Singh 《Natural resources forum》1999,23(1):65-77
This study discusses the use of non-timber forest products (NTFP), especially medicinal plants, by traditional communities in the western Himalaya, India. The great socio-cultural diversity and ecological complexity of the region is also matched by an unusually large variety of forest species being used. A wide range of plants, comprising herbs, shrubs and trees are used for different domestic purposes, such as food, fodder, materials for construction and handicrafts. Wild plants also play a vital role in providing primary health care in the region. In earlier times, forest products were harvested only on a subsistence basis. However, in recent decades, factors such as rising market demand, increasing population pressure, and changes in socio-cultural and socio-economic values have led to overharvesting. It is now estimated that most of the useful wild herbs in the region are overexploited and some of them have become locally extinct. Government forestry policies have, in the past, exclusively emphasized plantation and management of trees and have, unfortunately, ignored non-timber products, as these are usually of comparatively lesser economic importance. However, it is suggested that proper management of NTFP will help upgrade rural economies. Recommended policies to this effect include empowerment of local communities and their involvement in development plans as well as strengthening of indigenous knowledge. To foster sustainable use of NTFP, the following steps are also suggested: integrating traditional and scientific knowledge; safeguarding regeneration potential; cultivating wild species, making appropriate changes to extraction processes used; and establishing more transparency in prices and marketing channels. 相似文献
622.
Extensive production and consumption of nanomaterials such as ZnO and TiO2 has increased their release and disposal into the environment. The accumulation of nanoparticles (NPs) in ecosystem is likely to pose threat to non-specific targets such as bacteria. The present study explored the effect of ZnO and TiO2 NPs in a model bacterium, Salmonella typhimurium. The uptake of ZnO and TiO2 bare NPs in nano range without agglomeration was observed in S. typhimurium. TEM analysis demonstrated the internalization and uniform distribution of NPs inside the cells. Flow cytometry data also demonstrates that both ZnO and TiO2 NPs were significantly internalized in the S. typhimurium cells in a concentration dependent manner. A significant increase in uptake was observed in the S. typhimurium treated even with 8 and 80 ng mL−1 of ZnO and TiO2 NPs with S9 after 60 min, possibly the formation of micelles or protein coat facilitated entry of NPs. These NPs exhibited weak mutagenic potential in S. typhimurium strains TA98, TA1537 and Escherichia coli (WP2uvrA) of Ames test underscoring the possible carcinogenic potential similar to certain mutagenic chemicals. Our study reiterates the need for re-evaluating environmental toxicity of ZnO and TiO2 NPs presumably considered safe in environment. 相似文献
623.
Forest vegetation of a community managed forest (Van Panchayat) located between 1570–1700 m elevation was studied along four
aspects. Quercus leucotrichophora was the dominant species on three of the four aspects. Across the aspects the total tree density ranged between 150 and 490
ind/ha, sapling density between 100 and 370 ind/ha, seedling density varied from 241 to 1090 ind/ha. The shrub density ranged
from 166 to 690 ind/ha and herb density from 6000–17100 ind/ha. The total basal area of tree layer varied from 9.78 to 13.5
m2/ha showing that the forest is young. Species diversity value for tree layer varied from 0.14 to 1.69. Quercus leucotrichophora were regenerating well due to effective forest management by local communities. The higher proportion of seedlings of Quercus leucotrichophora indicating that the Van Panchayat are playing important role in conservation of oak forest of Himalaya. 相似文献
624.
Five woody plants species (i.e. Terminalia arjuna, Prosopis juliflora, Populus alba, Eucalyptus tereticornis and Dendrocalamus strictus) were selected for phytoremediation and grow on tannery sludge dumps of Common Effluent Treatment Plant (CETP), Unnao (Uttar Pradesh), India. Concentration of toxic metals were observed high in the raw tannery sludge i.e. Fe-1667 > Cr-628 > Zn-592 > Pb-427 > Cu-354 > Mn-210 > Cd-125 > Ni-76 mg kg−1 dw, respectively. Besides, physico-chemical properties of the raw sludge represented the toxic nature to human health and may pose numerous risks to local environment. The growth performances of woody plants were assessed in terms of various growth parameters such as height, diameter at breast height (DBH) and canopy area of plants. All the plant species have the capabilities to accumulate substantial amount of toxic metals in their tissues during the remediation. The ratio of accumulated metals in the plants were found in the order Fe > Cr > Mn > Pb > Zn > Cu > Cd > Ni and significant changes in physico-chemical parameters of tannery sludge were observed after treatment. All the woody plants indicated high bioconcentration factor for different metals in the order Fe > Cr > Mn > Ni > Cd > Pb > Zn > Cu. After one year of phytoremediation, the level of toxic metals were removed from tannery sludge up to Cr (70.22)%, Ni (59.21)%, Cd (58.4)%, Fe (49.75)%, Mn (30.95)%, Zn (22.80)%, Cu (20.46)% and Pb (14.05)%, respectively. 相似文献
625.
The molluscicidal activity of Sapindus mukorossi and Terminalia chebula fruit powder against the vector snail Lymnaea acuminata was time and concentration dependent. The molluscicidal activity of T. chebula fruit powder (96 h LC(50):93.59 mg L(-1)) was more pronounced than that of S. mukorossi fruit powder (96 h LC(50):119.57 mg L(-1)). Ethanolic extracts of S. mukorossi and T. chebula fruit powder were more toxic than their other organic solvent extracts. The molluscicidal activity of ethanolic extract of S. mukorossi fruit powder (24h LC(50):2.75 mg L(-1)) was more effective than the ethanolic extract of T. chebula fruit powder (24h LC(50):124.06 mg L(-1)). The 96 h LC(50) of column-purified fraction of S. mukorossi fruit powder was 5.43 mg L(-1) whereas those of T. chebula fruit powder was 7.49 mg L(-1). Column, thin layer and high performance liquid chromatography analysis demonstrates that the active molluscicidal component in S. mukorossi and T. chebula is saponin (96 h LC(50):1.31 mg L(-1)) and tannic acid (96 h LC(50):1.64 mg L(-1)), respectively. These plants may be used as potent source of molluscicides against the snail L. acuminata. 相似文献
626.
This work demonstrates the phytotoxicity screening of composted herbal pharmaceutical industry waste (HPIW) using seed bioassay method. The composted industrial waste should be tested at lab scale prior to recommendation for land application. HPIW was mixed with soil to produce four treatments: T(1) (1:1), T(2) (1:2), T(3) (1:3), and T(4) (1:0) for toxicity screening using Pisum sativum seeds. After 72?h relative seed germination (RSG), relative root growth (RRG) and germination index (GI) were recorded. Seedlings were observed for further plant growth and tissue biochemistry (chlorophyll, soluble sugar, starch, carotenoid, and protein) estimation. RSG, RRG, and GI values were better in T(1) and T(2) than others. GI was in the ranges of 36.62?% (T(4)) to 170.38?% (T(2)). The seedling growth and biochemical parameters were better in seedling obtained from potting media containing low proportion of HPIW (i.e., T(1) and T(2)). Results clearly suggested that composted HPIW may be utilized effectively for crop production after dilution under sustainable farming system program. 相似文献
627.
Methane is primarily a biogenic gas, which is implicated in global climate change. Among all the sources of methane emission, paddy fields form the most dominant source. An experiment was conducted with a common paddy crop (Oryza sativa var. Vishnuparag) by amending the soils with different organic manures and biofertilizers with a view to find out an inexpensive strategy to mitigate methane emission from the rice-fields. The results revealed that there was a seasonal change in the CH4 flux, registering a peak at heading stage in all treatments. The application of rice straw before flooding and the biofertilizer after flooding enhances CH4 efflux from the rice-fields significantly, while composts of cowdung and leaves did not stimulate CH4 production and, rather, decreased CH4 fluxes. As soil pH and temperature were optimum for methanogenesis, it was likely that the organic C and the redox potential mainly modulated methane production and its emission through rice plants. 相似文献
628.
M. K. Gupta Vibha Singh Poonam Rajwanshi Meetu Agarwal Kavita Rai Shalini Srivastava Rohit Shrivastav Sahab Dass 《Environmental monitoring and assessment》1999,59(3):275-285
Fluoride concentration and other parameters in groundwater from 261 villages in Tehsil Kheragarh of District Agra were assessed and attempts were made to observe the relationship between fluoride and other water quality parameters. Of 658 groundwater samples (collected from separate sources) analysed for fluoride, 27% were in the range of 0–1.0 mg/L, 25% in 1.0–1.5 mg/L, 32% in1.5–3.0 mg/L and 16% above 3.0 mg/L. The highest fluoride concentration recorded was 12.80 mg/L. Significant correlation of fluoride with pH, alkalinity, Na, SiO2 and PO4 were observed. Factor analysis was also attempted in order to identify the contributing sources. 相似文献
629.
B.K. Singh Aishwarya Jain Sumit Kumar B.S. Tomar Radha Tomar V.K. Manchanda S. Ramanathan 《Journal of contaminant hydrology》2009,106(3-4):144-149
Sorption of 137Cs, 90Sr, 154Eu and 141Ce by magnetite has been studied at varying pH (4 to 11) in the presence and absence of humic acid. The sorption studies have also been carried out at varying ionic strength (0.01 to 0.2 M NaClO4) and humic acid concentration (2 to 20 mg/L). Percentage sorption of 137Cs and 90Sr was found to be pH dependent, with the sorption increasing with increasing pH of the suspension. At any pH, the percentage sorption of 90Sr was higher than that of 137Cs. The results have been explained in terms of the electrostatic interaction between the positively charged metal ions and the surface charge of the magnetite which becomes increasingly negative with increasing pH. On the other hand, 154Eu and 141Ce were found to be strongly sorbed by the magnetite at all pH values, with the sorption being independent of pH. The strong sorption of trivalent and tetravalent metal ions suggests the role of complexation reactions during sorption, apart from the electrostatic interactions. However, in the case of 141Ce surface precipitation of Ce(III) formed by reduction of Ce(IV) in the presence of magnetite cannot be ruled out. Presence of humic acid (2 mg/L) was found to have negligible effect on sorption of all metal ions. 相似文献
630.
Poonam Singh Shashi Bhushan Agrawal 《Environmental pollution (Barking, Essex : 1987)》2009,157(3):871-880
A field study was conducted to evaluate the impact of ambient ozone on mustard (Brassica campestris L. var. Kranti) plants grown under recommended and 1.5 times recommended NPK doses at a rural site of India using filtered (FCs) and non-filtered open top chambers (NFCs). Ambient mean O3 concentration varied from 41.65 to 54.2 ppb during the experiment. Plants growing in FCs showed higher photosynthetic rate at both NPK levels, but higher stomatal conductance only at recommended NPK. There were improvements in growth parameters and biomass of plants in FCs as compared to NFCs at both NPK levels with higher increments at 1.5 times recommended. Seed yield and harvest index decreased significantly only at recommended NPK in NFCs. Seed quality in terms of nutrients, protein and oil contents reduced in NFCs at recommended NPK. The application of 1.5 times recommended NPK provided protection against yield loss due to ambient O3. 相似文献