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101.
The field study was conducted to evaluate the effect of municipal solid waste compost (MSWC) as a soil amendment on L-asparaginase (LA) and L-glutaminase (LG) activities. Experiments were conducted during the wet seasons of 1997, 1998 and 1999 on rice grown under a submerged condition, at the Agriculture Experimental Farm, Calcutta University at Baruipur, West Bengal, India. The treatments consisted of control, no input; MSWC, at 60 Kg N ha? 1; well-decomposed cow manure (DCM), at 60 Kg N ha? 1; MSWC (30 Kg N ha? 1) + Urea (U) (30 Kg N ha? 1); DCM (30 Kg N ha? 1) + U (30 Kg N ha? 1) and Fertilizer, (at 60:30:30 NPK kg ha? 1) through urea, single superphosphate and muriate of potash respectively). LA and LG activities alone and their ratio with organic-C (ratio index value, RIV), straw and grain yield were higher in DCM than MSWC-treated soils, due to higher amount of biogenic organic materials like water-soluble organic carbon, carbohydrate and mineralizable nitrogen in the former. The studied parameters were higher when urea was integrated with DCM or MSWC, compared to their single applications. The heavy metals in MSWC did not detrimentally influence the above-measured activities of soil. In the event of long term MSWC application, changes in soil quality parameters should be monitored regularly, since heavy metals once entering into soil persist over a long period.  相似文献   
102.
The small scale forestry carbon project in Haryana, India has been registered as a Clean Development Project (CDM) activity and is the first such projects from India. Developed under the Kyoto Protocol of United Nations Framework Convention on Climate Change (UNFCCC), the projects aims at restoring heavily degraded sandune affected private lands and contribute to climate change mitigation. The project is expected to sequester 234,584 tons of carbon dioxide (tCO2) in 20 years project cycle with an average annual sequestration of 11,729 (tCO2) per year. The project is expected to have a total carbon stock of 385,253.1 ton Carbon (tC) in the project life span of 20 years as against 7,920.6 (tC) in the baseline scenario. The carbon credits earned from the project is supposed to provide additional incentives to the smallholders who have formed a cooperative society for this purpose. This paper addresses the issues and challenges in developing the project activity and also discusses the lessons learned in the process. The project is supposed to help in poverty alleviation and has become a success story for rehabilitating degraded lands in semi arid regions of India through plantation forestry.  相似文献   
103.
A study on the toxicokinetic behavior, metabolism of chlorpropham, and its effect on cytochrome P450 from liver microsomes was carried out in albino rats after a single and consecutive oral administration at 500?mg?kg?1 body weight for 10 and 20 days. Chlorpropham was detected in the blood at 0.08?h (11.43?±?1.72?µg?mL?1) reaching a maximum concentration at 2?h (30.90?±?2.55?µg?mL?1) and a minimum at 48?h (1.95?±?0.20?µg?mL?1) after a single oral administration of 500?mg?kg?1. The absorption rate constant (K a) was 0.66?±?0.48?h?1. The Vd area (18.01?±?2.78?L?kg?1) and t 1/2 β (12.23?±?1.96?h) values suggested a wide distribution and long persistence of the compound in the body, respectively. The higher ClR (0.82?±?0.00?L?kg?1?h?1) compared to ClH (0.18?±?0.02?L?kg?1?h?1) value indicated that a major portion of chlorpropham was excreted through the urine (30%) compared to the faeces (2.81%). Chlorpropham residue was detected in all tissues of rat at 0.25?h while its metabolite, meta-chloroaniline was detected in liver, kidney, heart, lung, and spleen tissue at 0.25?h. Meta-chloroaniline was not detected in skeletal muscle, brain, fat, and stomach tissue at any time of the observation period. Maximum concentrations of chlorpropham and meta-chloroaniline were detected at 2?h (except in the spleen), and minimum concentrations of chlorpropham at 24 (heart, lung, spleen, skeletal muscle, and stomach) and 48?h (liver, kidney, brain, and fat tissue) respectively; and meta-chloroaniline at 24?h (except heart and spleen). The tissue half-life of chlorpropham in rat varied from 3.80 to 11.60?h. Repeated oral administration of chlorpropham at 500?mg?kg?1 for 10 and 20 days caused an induction of the liver microsomal pellet of rat.  相似文献   
104.
This paper reports on the pollution profile of Damodar river sediment as obtained from analysis of the river sediment at suitable selected sites in the Raniganj-Durgapur industrial belt, West Bengal, India. The parameters measured include (a) silica, mixed oxide, calcium, magnesium, total water-soluble exchangeable cation and anion, chemical oxygen demand, and (b) some toxic and other elements, such as sodium, potassium, arsenic, cadmium, chromium, mercury, manganese, lead, zinc, cobalt, copper, iron nickel, phosphorus, sulphur, and vanadium. The parameters listed under (a) led to the characterization of the sediment, and those under (b) gave an index of metal pollution of the sediment. The elements were estimated by inductively coupled plasma emission spectrometry.  相似文献   
105.
In vitro methane emissions from different rice paddy soils and algal mats were studied under anoxic and atmospheric conditions. Methane production from rice paddy soils cultivating different strains of rice was found to be appreciable under anoxic conditions, but considerably reduced under atmospheric conditions, and dependent on rice cultivars (strains). A contradictory result was obtained with a Gobindabhog cultivated rice field (a strain of rice with aroma), where methane yield under anoxic was greater than that under atmospheric conditions. The results indicated aerotolerance of methanogens or the possible existence of microaerophilic methanogens. The results from algal mats corroborated these findings.Methane has been considered to be an important greenhouse gas contributing significantly to global thermal warming (GTW). Flooded rice paddy fields have been considered to be a most prominent source of abiogenic methane emission, though considerable uncertainty exists regarding the true estimates of methane emission. Factors affecting methane emission and its abatement have been examined. In spite of increasing methane emission, rice cultivation leads to enormous utilization of the green house gas carbon dioxide and release of oxygen to the atmosphere. Thus, the contribution of methane to GTW (from rice paddy cultivation) is more than compensated by carbon dioxide absorption.Appropriate steps have been suggested for the reduction of methane emissions, the most important of which is the restoration of methane sinks.  相似文献   
106.
The use of pharmaceuticals during pregnancy may causes abnormalities to the embryo. Sometime the drug also effect to the new born if the drug transferred through lactation. We have used zebrafish model to see the effect of some pharmaceuticals on embryos and larvae. Three drugs, caffeine, norfloxacin and nimesulide, were used for this study to see the effect mainly the hatching rate of eggs, heart beat rate and the vascular endothelial growth factor (VEGF) expression of the larvae. VEGF is an important signaling protein that involved generating the new blood vessels during embryonic development. We have used 10, 20, 50, 100 microg ml(-1) concentrations of all the drugs to see the effect. No significant mortality or malformations were observed in zebrafish embryos. Hatching was stared from 60 hr. In control group, 91% hatching rate was observed. Lowest hatching rate was observed using highest concentration of norfloxacin (100 microg ml(-1)) and nimesulide (100 microg ml(-1)) i.e. 55 and 56% respectively. In control group, 110 to 115 heart beat rate was counted per minute. Significantly higher heart beat was observed in caffeine treated group which is 125 to 140 min(-1) Lower heart beat was noted in nimesulide treated group which is 100 min(-1). We have tried to observe the possible effect of VEGF of the larvae by these three drugs. Expression of VEGF was very low in caffeine treated group. Almost no VGF expression was observe in 100 microg ml(-1) caffeine treated group. These studies suggest that there is a possibility that high dosage of caffeine can harm the unborn baby or new born babies, if the mothers use caffeine.  相似文献   
107.
Environmental Science and Pollution Research - The rapid degradation, overexploitation, and encroachment of floodplain wetlands have led to considerable decline in fish diversity and production...  相似文献   
108.
Environmental Science and Pollution Research - Global agriculture is facing tremendous challenges due to climate change. The most predominant amongst these challenges are abiotic and biotic...  相似文献   
109.
Biomethanation as a result of co-culturing methanogenic bacteria with sulphate-reducing bacteria was studied under anoxic conditions. Toxic sulphur compounds are known not to inhibit methanogenesis. Hence varying experimental conditions can lead to the optimum conditions for biomethanation. Under controlled experimental conditions, the interacting behaviour of both isolated methanogens and sulphate reducers show interesting features, viz. allelopathy.  相似文献   
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