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61.
62.
By sampling an upland settlement project (USP) village, this study examined why the project failed to achieve the planned objectives in some villages, and what livelihood strategies villagers (planters) have adopted to sustain their livelihoods. The paper uses data obtained by qualitative and quantitative methods. The USP was formulated with the objectives of settling 50 landless and marginal tribal families in a project village and introducing agroforestry and rubber plantations for short- and long-term socioeconomic development of planters, in a participatory manner. There are now only 15 planters in the project village and, although agroforestry has progressed well, only 30 to 40% of poor quality rubber trees remain. Planter participation in project activities was limited to wage labour, indicating that the USP failed to adequately achieve all its proposed objectives. In the face of project failure, planters have adopted diversified strategies to maintain their livelihoods. Several shortcomings caused failure of the project, such as the inability of project staff members to organize planters, failure to create awareness among planters about project benefits, lack of regular project money disbursement, sociocultural ignorance, and lack of social capital among planters. Recommendations are made for securing effective participation of local people to assure successful and sustainable project outcomes. Lessons learned will be helpful in formulating future development programmes in this country and elsewhere.  相似文献   
63.
Reduction in DNA repair capacity is associated with increased rates of birth defects, cancer, and accelerated ageing. Genetic polymorphisms in DNA repair genes might influence the repair activities of the enzymes predisposing individuals to cancer risk. Owing to the presence of these genetic variants, inter-individual and ethnic differences in DNA repair capacity have been observed in various populations. India harbors enormous genetic, cultural and linguistic diversity. The present study was undertaken to determine the allele and genotype frequencies of four non-synonymous SNPs, XRCC1 Arg399Gln (C > T, rs25487), XRCC3 Thr241Met (G > A, rs861539), XPD Lys751Gln (T > G, rs13181), and OGG1 Ser326Cys (C > G, rs1052133) in the Maharashtrian population, residing in the Vidarbha region of central India and to compare them with HapMap and other Indian populations. The variant alleles of these polymorphisms have been found to be positively associated with different forms of cancer in several genetic epidemiological studies. The basic prevalence of these polymorphisms in the general population must be known to evaluate their significance in risk assessment in cancer and other phenotypes. About 215 healthy and unrelated individuals from the Maharashtrian population were genotyped for each of these four polymorphisms using PCR-RFLP. The allele and genotype frequency distribution at the four DNA repair gene loci among Maharashtrians revealed a characteristic pattern. To the best of our knowledge, this is the first report of these DNA repair gene polymorphisms in a central Indian population.  相似文献   
64.
Environmental occurrence of CECs poses a great threat to both aquatic life and human health. The aim of this study was to optimize and validate SPE/LC-(ESI)MS-MS method for simultaneous quantitative monitoring of two sub-classes of CECs (pharmaceuticals and hormones) and to estimate the concentrations of select CECs in environmental water samples. For all the tested analytes, recoveries in laboratory reagent water were greater than 81%. Average percent (relative standard deviation) RSD of the analytes in recovery, repeatability, and reproducibility experiments were ≤?10%. Determination coefficients (r2) of primidone, diclofenac, testosterone, and progesterone were estimated to be 0.9979, 0.9972, 0.9968, and 0.9962, respectively. Limits of detection (LOD) for primidone, diclofenac, testosterone, and progesterone were 4.63 ng/L, 5.36 ng/L, 0.55 ng/L, and 0.88 ng/L, respectively. Limits of quantification (LOQ) for primidone, diclofenac, testosterone, and progesterone were 14.72 ng/L, 17.06 ng/L, 1.766 ng/L, and 2.813 ng/L, respectively. Average recoveries in environmental water and wastewater samples were greater than 74% and RSD were ≤?7%. Trace levels (68.33–125.70 ng/L) of primidone were detected in four environmental water samples, whereas diclofenac was not detected in any of the tested sample. Trace levels of progesterone were observed in two environmental samples (16.64 –203.73 ng/L), whereas testosterone was detected in STP inlet sample (178.16 ng/L).  相似文献   
65.
The effect of heavy metals on the activities of earthworm species Eudrillus eugineae was studied during vermicomposting of municipal solid waste (MSW) spiked with heavy metals. The activities of earthworms, in terms of growth and biomass production and number of cocoons produced, were monitored periodically, and the concentration of heavy metals in earthworms and substrates was determined at definite intervals. Laboratory-scale experiments were performed by mixing individual heavy metals in MSW. Copper, cadmium, chromium, lead, and zinc were selected for the study. The study concludes that heavy metals tend to accumulate in the body of earthworms; hence, the inherent concentration of heavy metals in the substrate before vermicomposting must be considered in view of composting of MSW and its application to soil. It was observed that copper and cadmium were toxic for the worms at 1.5 and 0.1 g/kg of the waste, respectively. The studies also suggest that earthworms are susceptible to the free form of heavy metals. Cadmium is the most toxic metal, followed by copper. Based on the investigation and observation, it was also found that earthworms should be separated from castings before the use of castings in soil amendments.  相似文献   
66.
67.
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   
68.
Dynamics of heavy metals such as Fe, Mn, Zn, Cr, Cu, Co, Ni, Pb, and Cd in surface water of Mahanadi River estuarine systems were studied taking 31 different stations and three different seasons. This study demonstrates that the elemental concentrations are extremely variable and most of them are higher than the World river average. Among the heavy metals, iron is present at highest concentration while cadmium is at the least. The spatial pattern of heavy metals suggests that their anthropogenic sources are possibly from two major fertilizer plants and municipal sewage from three major towns as well as agricultural runoff. The temporal variations for metals like Fe, Cu, and Pb exhibit higher values during the monsoon season, which are related to agricultural runoff. Concentrations of Ni, Pb, and Cd exceed the maximum permissible limits of surface water quality in some polluted stations and pose health risks. Dissolved heavy metals like Fe, Mn, Cr, Ni, and Pb exhibit a non-conservative behavior during estuarine mixing, while Zn, Cu, and Co distribution is conservative. Distribution of cadmium in the estuarine region indicates some mobilization which may be due to desorption. The enrichment ratio data suggest that various industrial wastes and municipal wastes contribute most of the dissolved metals in the Mahanadi River. The Mahanadi River transports 18.216 × 103 t of total heavy metals into the Bay of Bengal and the calculated rate of erosion in the basin is 128.645 kg km − 2 year − 1.  相似文献   
69.
The main aim of this study was to assess the impact of pesticidal residues on soil microbial and biochemical parameters of the tea garden soils. The microbial biomass carbon (MBC), basal (BSR) and substrate induced respirations (SIR), β -glucosidase activity and fluorescein diacetate hydrolyzing activity (FDHA) of six tea garden soils, along with two adjacent forest soils (control) in West Bengal, India were measured. The biomass and its activities and biochemical parameters were generally lower in the tea garden soils than the control soils. The MBC of the soils ranged from 295.5 to 767.5 μ g g? 1. The BSR and SIR ranged from 1.65 to 3.08 μ g CO2-C g? 1 soil h? 1 and 3.08 to 10.76 μ g CO2-C g? 1h? 1 respectively. The β -glucosidase and FDHA of the soils varied from 33.3 and 76.3 μ g para-nitrophenol g? 1 soil h? 1 and 60.5 to 173.5 μ g fluorescein g? 1h? 1respectively. The tea garden soils contained variable residues of organophosphorus and organochlorine pesticides, which negatively affected the MBC, BSR, SIR, FDHA and β -glucosidase activity. Ethion and chlorpyriphos pesticide residues in all the tea garden soils varied from 5.00 to 527.8 ppb and 17.6 to 478.1 ppb respectively. The α endosulfan, β endosulfan and endosulfan sulfate pesticide residues in the tea garden soils ranged from 7.40 to 81.40 ppb, 8.50 to 256.1 ppb and 55 to 95.9 ppb respectively. Canonical correlation analysis shows that 93% of the total variation was associated with the negative impact of chlorpyriphos, β and α endosulfan and endosulfan sulfate on MBC, BSR and FDHA. At the same time ethion had negative impact on SIR and β -glucosidase. Data demonstrated that the pesticide residues had a strong impact on the microbial and biochemical components of soil quality.  相似文献   
70.
Enrichment and isolation of endosulfan degrading and detoxifying bacteria   总被引:1,自引:0,他引:1  
In the present study, degradation of endosulfan by a mixed culture isolated from a pesticide-contaminated soil was studied in batch experiments. After two weeks of incubation, the mixed culture was able to degrade 73% and 81% of alpha and beta endosulfan respectively. Endodiol was identified by GC/MS as degradation intermediate. The toxicity studies of endosulfan before and after degradation were carried out using micronucleus assay on human polymorphonuclear cells. The findings suggested that the metabolism of endosulfan isomers by the mixed culture was accompanied by significant reduction in the toxicity. Studies were also carried out to quantify the degradation potential of the individual species in the mixed bacterial culture. Two cultures identified by 16S rRNA as Stenotrophomonas maltophilia and Rhodococcus erythropolis were found to be responsible for majority of the degradation by the mixed culture. S. maltophilia showed better degradation efficiency compared to that by R. erythropolis. This is the first report of endosulfan degradation using the above-mentioned organisms.  相似文献   
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