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201.
Tripathi RD  Vajpayee P  Singh N  Rai UN  Kumar A  Ali MB  Kumar B  Yunus M 《Chemosphere》2004,54(11):1581-1588
Plants of Cassia siamea Lamk were grown in garden soil (control), fly-ash (100%) and fly-ash amended by various ameliorants (cowdung manure, press-mud, garden soil; 1:1, w/w). The plants survived in fly-ash (100%) though their growth was less in comparison to the treatments. Fly-ash+press-mud (1:1, w/w) proved to be the best combination as growth (total biomass, leaf number, photosynthetic area, total chlorophyll and protein) was significantly high in this treatment followed by cowdung manure and garden soil. Leaves and roots accumulated significant amount of Cu, Zn, Ni and and Fe. However, the concentration of all the metals was more in roots than leaves except Ni. Although, fly-ash contains high amount of metals but the metal uptake was more in the plants grown in fly-ash+press-mud mixture. Inspite of high metal availability in fly-ash and press-mud mixture, plant growth was good. This might be attributed to the some metal detoxification mechanism active in this treatment. The present study concluded that C. siamea seems to be a suitable plant for developing a vegetation cover on fly-ash dumps.  相似文献   
202.
Insecticide residues in cotton crop soil   总被引:2,自引:0,他引:2  
Dimethoate, monocrotophos, triazophos, deltamethrin, cypermethrin and endosulfan were applied to a cotton crop soil located at Nurpur village, Punjab, India. The insecticides were applied sequentially at recommended dosages in cotton fields by foliar application in 1995, 1996 and 1998. Soil samples were collected from the cotton crop farms and extracted with acetone. The extracted material was analysed by a gas liquid chromatograph (GLC) equipped with an 63Ni electron-capture detector (ECD-63Ni). Recovery data was obtained by fortifying soil with insecticide. The average recoveries from the fortified soil samples were 76-92% for organophosphorous compounds and 90-98% for synthetic pyrethroids and organochlorines. The results showed that the insecticide residues under study were present in the range of 1.16 to 41.97 ng g(-1) d.wt.soil. The pattern of dissipation of the insecticides used was similar for the duration of the crop. Half lives of the insecticides ranged from 7 to 22 days. Except endosulfan none of the other insecticides used were leached below 15 cm. Endosulfan was found to be rapidly degraded in the soil and formed a sulfate metabolite. Persistence and dissipation pattern in soils with history of exposure to the insecticide compared to non-history soils were similar.  相似文献   
203.
The effect of five concentrations (10 mM, 1 mM, 0.1 mM, 0.01 mM and 0.001 mM) of mercury on the rate of absorption of glucose, fructose, glycine and tryptophan by the intestine of the fresh water murrel Channapunctatus has been studied. Intestinal absorption of these nutrients was also examined in fish exposed to a sublethal concentration (3 μg/l) of mercury for 15 and 30 days. Significant decrease was recorded in the rate of intestinal absorption of all the four nutrients with higher concentrations (10 mM, 1 mM and 0.1 mM) of mercury. 0.01 mM and 0.001 mM of mercury also reduced the transport rate but it was insignificant, except in case of tryptophan, where 0.01 mM of mercury also produced significant decrease. Exposure of fish by bath to mercury also resulted in significant decrease in the intestinal transport rate of all the four nutrients after 30 days.  相似文献   
204.
Environmental Science and Pollution Research - The huge demand and consumption of DOX, its incomplete metabolism, and complex behavior in atmosphere are causing a great ecological issue, which...  相似文献   
205.
206.
Environmental Science and Pollution Research - In this study, we are reporting a novel prediction model for forecasting the carbon dioxide (CO2) fixation of microalgae which is based on the hybrid...  相似文献   
207.
208.
A survey was conducted in Uttar Pradesh to enlist the available exotic fish species in culture. The culture and feeding details of unofficially introduced Clarias gariepinus was collected from 419 ponds existing in rural areas of 23 districts of Uttar Pradesh. The data indicated that 32% ponds were culturing exotic fishes of which 79% cases are of monoculture of exotic African catfish. Feeding analysis of these exotic African catfish revealed that 7% cases subsist on natural pond feed while 29% cases are fed on slaughter house waste. In 32% cases of the exotic magur monoculture, chicken waste was given whereas 11% cases were recorded with fish waste feeding. The possible threats and environmental risks of such unauthorised and indiscreminate culture of exotic magur has been discussed in this paper.  相似文献   
209.
Socioecological theory suggests that between-group competition is an important factor affecting the nature of primate social relationships. Between-group encounters in macaques may involve female resource defense, male mate defense, and male resource defense. We observed between-group encounters in two groups (a forest group and a temple group) of bonnet macaques (Macaca radiata). We observed 102 encounters in 875 h of observation of the forest group (1.40 per 12-h day) and 58 encounters in 907 h of observation of the temple group (0.77 per 12-h day). Aggressive interactions between groups occurred in 32.4% and 29.3% of encounters in the forest and temple groups, respectively. Overall, we found little support for the female resource defense hypothesis. Females in both groups rarely participated aggressively in between-group encounters. We found support for the male mate defense hypothesis. For example, males of the forest group were more aggressive during encounters in the mating season than in the non-mating season. Males were also aggressive to females from their own group immediately following encounters. We also found partial support for the male resource defense hypothesis. Encounters in the forest group occurred in a feeding context more often than expected based on time budgets. Also, males in the temple group were more often aggressive in food-related encounters than in other encounters. The findings of this study suggest that socioecological models of primate social relationships need to distinguish male and female strategies during between-group encounters and integrate the resulting functional outcomes.Communicated by T. Czeschlik  相似文献   
210.
Comparative hepatic and renal toxicity of cadmium in male and female rats   总被引:3,自引:0,他引:3  
Rats (male and female) were exposed to 0.5 mg/kg and 1 mg/kg cadmium as cadmium chloride for 3 days and subsequently sacrificed for cadmium concentration and other biochemical variables indicative of hepatic and renal damage. The absorption of cadmium was supported by biochemical changes, which were significantly higher in females than in males. This could be due to higher rate of intestinal absorption of cadmium in females than males. Male and female rats both showed relatively higher cadmium concentration in kidneys than in liver. Female rats also showed the similar trend in tissue metal levels as compared to male rats. However, hepatic and renal histopathological observations showed that female rats suffered from severe hepatic injury like hydropic degeneration of hepatocytes, granulation, bile duct proliferation etc. In comparison to female rats, male rats did not show much remarkable changes. Renal damage was more prominent in female than male in the form of renal tubular damage; most of the tubular nuclei were pyknotic, congestion of the boundary of cortex and medulla etc. The results suggested that females were comparatively more vulnerable to the toxic effects of cadmium than males.  相似文献   
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