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91.
Despite over two decades of efforts towards involving indigenous and traditional peoples in protected area management, there are few successful examples. Several international principles and guidelines on indigenous peoples' involvement in protected areas exist. However, because of the lack of evaluation of whether or not these principles and guidelines have been put into practice, there is hardly any information that indicates the actual involvement of indigenous peoples in protected areas. This paper attempts to compare efforts in partnership between indigenous peoples and protected area authority in three Asian countries: Nepal, Thailand, and China. It shows that the involvement of indigenous peoples is more successful where park planning is participatory and where political and socioeconomic reforms are underway. Indigenous peoples are in conflict with park authorities where park management is centralized and nonparticipatory. Unless concrete efforts are made to address livelihood issues of indigenous peoples living in and around protected areas, park management aimed to protect wildlife will rarely succeed. Participatory park management that involves indigenous peoples and that addresses livelihood issues of indigenous communities will ultimately succeed in its efforts toward wildlife conservation.  相似文献   
92.
ABSTRACT

The limitation of self-excited induction generator (SEIG) when used in the stand-alone wind energy system (WES) is poor voltage regulation at variable speed. The indirect vector control (IVC) technique is employed for both the generator-side converter (GSC) and load-side converter (LSC) to regulate the variation of SEIG speed, DC link voltage, and electromagnetic torque independently. Further performance of the proposed IVC technique has been analyzed independently with neural network controller (NNC) and fuzzy logic controller (FLC) as its components. The FLC is replaced by an NNC to improve the performance of the proposed system. IVC of SEIG-based WES has been simulated in MATLAB/SIMULINK software, and the prototype model of the proposed WES is developed to experimentally validate the performance using dSPACE DS-1104 R&D controller board.  相似文献   
93.
Water samples from 30 rivers in northern and north-eastern hilly states of India were analysed for bacteriological and physicochemical parameters along with metals and pesticide residues. It was found that 34% of samples had >50 coliforms/100 ml, while 24% of samples demonstrated >50 thermotolerant (faecal) coliforms/100 ml. Among the metals, iron was found to be above maximum permissible limits in the rivers of all the states, while manganese was found to be above the maximum permissible limit in the rivers of Tripura and some northern states. Zinc, lead, nickel, chromium, copper, cobalt and cadmium plus physicochemical parameters and residual pesticides, however, were within their maximum permissible limits.  相似文献   
94.
Methanogens, the members of domain Archaea are potent contributors in global warming. Being confined to the strict anaerobic environment, their direct cultivation as pure culture is quite difficult. Therefore, a range of culture-independent methods have been developed to investigate their numbers, substrate uptake patterns, and identification in complex microbial communities. Unlike other approaches, fluorescence in situ hybridization (FISH) is not only used for faster quantification and accurate identification but also to reveal the physiological properties and spatiotemporal dynamics of methanogens in their natural environment. Aside from the methodological aspects and application of FISH, this review also focuses on culture-dependent and -independent techniques employed in enumerating methanogens along with associated problems. In addition, the combination of FISH with micro-autoradiography that could also be an important tool in investigating the activities of methanogens is also discussed.  相似文献   
95.

Polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and phenolic compounds (PCs) are persistent organic compounds. Contamination of these potentially toxic organic pollutants in soils and sediments is most studied environmental compartments. In recent past, studies were carried out on PAHs, OCPs and PCs in various soils and sediments in India. But, this is the first study on these pollutants in soils and sediments from an urbanized river flood plain area in Delhi, India. During 2018, a total of fifty-four samples including twenty-seven each of soil and sediment were collected and analyzed for thirteen priority PAHs, four OCPs and six PCs. The detected concentration of ∑PAHs, ∑OCPs and ∑PCs in soils ranged between 473 and 1132, 13 and 41, and 639 and 2112 µg/kg, respectively, while their concentrations in sediments ranged between 1685 and 4010, 4.2 and 47, and 553 and 20,983 µg/kg, respectively. PAHs with 4-aromatic rings were the dominant compounds, accounting for 51 and 76% of total PAHs in soils and sediments, respectively. The contribution of seven carcinogen PAHs (7CPAHs) in soils and sediments accounted for 43% and 61%, respectively, to ∑PAHs. Among OCPs, p, p’-DDT was the dominant compound in soils, while α-HCH was found to be dominated in sediments. The concentrations of ∑CPs (chlorophenols) were dominated over ∑NPs (nitrophenols) in both the matrices. Various diagnostic tools were applied for the identification of their possible sources in soil and sediments. The observed concentrations of PAHs, OCPs and PCs were more or less comparable with the recently reports from various locations around the world including India. Soil quality guidelines and consensus-based sediment quality guidelines were applied for the assessment of ecotoxicological health effect.

  相似文献   
96.
Deltamethrin, a pyrethroid insecticide widely used in many countries, causes significant adverse effects in aquatic ecosystems. The concentration of deltamethrin in water reservoirs and the run off from agricultural areas (in water) in many countries range up to 24.0?µg?L?1 which is higher than the recommendation of the European Union standard. Hence, in this study the effects of deltamethrin were investigated, i.e. its toxic impacts on the freshwater catfish Heteropneustes fossilis in terms of serum calcium and prolactin cells (located in the rostral pars distalis region of the pituitary). The fish were subjected to deltamethrin for a short-term experiment (96?h; 1.5?µg?L?1 e.0.8 of 96?h LC50) and a long-term experiment (28 days; 0.37?µg?L?1 e.0.2 of 96?h LC50). After short-term deltamethrin exposure, serum calcium levels decrease. No histological change in prolactin cells is noticed throughout the short-term experiment. Fish exposed to deltamethrin for 7 days also exhibit a decrease in serum calcium level. This decrease persisted until the end of the experiment (28 days). Prolactin cells of fish treated for 14 days with deltamethrin exhibit increased nuclear volume and degranulation, increasing progressively from the 21st day onwards. After 28 days, a few degenerated cells are discerned. The results of this study show that deltamethrin is moderately toxic for the freshwater fish H. fossilis by producing adverse effects on serum calcium and prolactin cells. Hence, it should be used with caution in areas near fish-inhabited waters.  相似文献   
97.
The results of dissolution experiments for benzene, toluene, m-xylene and naphthalene (BTXN) from a relatively insoluble oil phase (tridecane), residually trapped in a non-sorbing porous medium, are described. This mixture was chosen to simulate dissolution of soluble aromatic compounds from a petroleum hydrocarbon mixture, e.g., crude oil, for which a large fraction of the mixture is relatively insoluble. The experiments were carried out at a small source length to interstitial velocity ratio, L/v, so that dissolution would be mass transfer limited (MTL). When fitted to data for toluene, a multiregion mass transfer model was found to predict the experimental data satisfactorily for the other components without adjustment of the mass transfer rate parameters. These results indicate that the dissolution process can be generalized for various hydrophobic organic compounds present in a multicomponent non-aqueous phase liquid (NAPL) when mass transfer limitations are present. This also suggests that dissolution data obtained for one compound can be useful for predicting the dissolution histories for other compounds from petroleum hydrocarbon mixtures.  相似文献   
98.
A. sydowii strain bpo1 exhibited 99.8% anthracene degradation efficiency. • Four unique metabolic products were obtained after anthracene degradation. • Ligninolytic enzymes induction played vital roles in the removal of anthracene. • Laccase played a crucial role in comparison with other enzymes induced. The present study investigated the efficiency of Aspergillus sydowii strain bpo1 (GenBank Accession Number: MK373021) in the removal of anthracene (100 mg/L). Optimal degradation efficiency (98.7%) was observed at neutral pH, temperature (30℃), biomass weight (2 g) and salinity (0.2% w/v) within 72 h. The enzyme analyses revealed 131%, 107%, and 89% induction in laccase, lignin peroxidase, and manganese peroxidase respectively during anthracene degradation. Furthermore, the degradation efficiency (99.8%) and enzyme induction were significantly enhanced with the addition of 100 mg/L of citric acid and glucose to the culture. At varying anthracene concentrations (100–500 mg/L), the degradation rate constants (k1) peaked with increasing concentration of anthracene while the half-life (t1/2) decreases with increase in anthracene concentration. Goodness of fit (R2 = 0.976 and 0.982) was observed when the experimental data were subjected to Langmuir and Temkin models respectively which affirmed the monolayer and heterogeneous nature exhibited by A. sydwoii cells during degradation. Four distinct metabolites; anthracene-1,8,9 (2H,8aH,9aH)-trione, 2,4a-dihydronaphthalene-1,5-dione, 1,3,3a,7a-tetrahydro-2-benzofuran-4,7-dione and 2-hydroxybenzoic acid was obtained through Gas Chromatography-Mass spectrometry (GC-MS). A. sydowii exhibited promising potentials in the removal of PAHs.  相似文献   
99.
Environmental Science and Pollution Research - Metalloids are a subset of particular concern to risk assessors and toxicologists because of their well-documented potential hazards to plant system....  相似文献   
100.
In order to study the distribution and ecotoxicological concerns of persistent organic pollutants, grab sediment samples were collected from different locations across Thane creek, India. Analyses of samples were carried out using gas chromatography (GC)–electron capture detector and GC–mass spectrometry techniques. In organochlorine pesticides (OCPs), DDT (1,1,1,-trichloro-2,2-bis(p-chlorophenyl) ethane), DDE (1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene), DDD (1-chloro-4-(2,2-dichloro-1-(4-chlorophenyl)ethyl) benzene) and α, β, and γ conformer of hexachlorocyclohexane (HCH), and 9 polychlorinated biphenyls (PCBs) congeners were analyzed in surface sediment samples. Concentrations of these pollutants in grab sediment samples may indicate their current use and impact on marine ecosystem. Average concentrations of total DDT (including DDD and DDE), HCH, and Σ9PCBs were found to be 4.9, 12.5, and 2.9 µg kg?1(dry weight) respectively. High concentrations of OCPs and PCBs were found at discharge locations in creek compared to other locations. Location-wise distribution of OCPs and PCBs indicates their high concentrations at the waste water receiving point. Data were compared for ecotoxicological impacts based on the levels specified in the sediment quality standards of the US Environmental Protection Agency and the Canadian Council of Ministers of the Environment. γ-HCH was found to have maximum potential to induce ecotoxicological impacts.  相似文献   
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