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861.
B. Ravindran S. M. Contreras-Ramos J. W. C. Wong A. Selvam G. Sekaran 《Environmental science and pollution research international》2014,21(1):641-651
Animal fleshing (ANFL) is the predominant proteinaceous solid waste generated during processing of leather and it is confronting disposal problems. The aim of this study was to assess the potential of epigeic earthworm Eudrilus eugeniae to utilize and transform the fermented ANFL in the solid state (SSF) and submerged state (SmF) into a value added product along a low residence period (25 days). A total of six treatment units containing different waste mixture compositions were established. Fifty healthy and non-clitellated earthworms were introduced in three different treatment containers: control, SSF, and SmF (+worm). Another set of treatment mixtures (control, SSF, SmF) was established without earthworms (?worm) to compare the results. The products were characterized for physico-chemical, enzymatic analysis and seedling growth parameters to compare the differences in the process with and without earthworms. The changes observed in the analytical parameters were in the following order: SSF > SmF > control mixtures (p?<?0.05). The vermicompost showed a significant reduction in heavy metals, total organic carbon and an increase in total Kjeldhal nitrogen as compared to the product untreated by earthworms. The maximum enzymatic activities were observed after 21 days of vermicomposting. The relative seed germination of vermicompost extracts were in the order of tomato (Lycopersicon esculentum) > green gram (Vigna radiata) > cucumber (Cucumis sativus) > bottle gourd (Lagenaria siceraria (Mol.) Standl.) and showed no phytotoxicity effects. The results indicated that the combination of both ANFL hydrolysis through fermentation and vermicomposting is a good alternative to the management of this kind of waste. 相似文献
862.
M. St. J. Warne G. E. Batley O. Braga J. C. Chapman D. R. Fox C. W. Hickey J. L. Stauber R. Van Dam 《Environmental science and pollution research international》2014,21(1):51-60
The Australian and New Zealand Guidelines for Fresh and Marine Water Quality are a key document in the Australian National Water Quality Management Strategy. These guidelines released in 2000 are currently being reviewed and updated. The revision is being co-ordinated by the Australian Department of Sustainability, Environment, Water, Population and Communities, while technical matters are dealt with by a series of Working Groups. The revision will be evolutionary in nature reflecting the latest scientific developments and a range of stakeholder desires. Key changes will be: increasing the types and sources of data that can be used; working collaboratively with industry to permit the use of commercial-in-confidence data; increasing the minimum data requirements; including a measure of the uncertainty of the trigger value; improving the software used to calculate trigger values; increasing the rigour of site-specific trigger values; improving the method for assessing the reliability of the trigger values; and providing guidance of measures of toxicity and toxicological endpoints that may, in the near future, be appropriate for trigger value derivation. These changes will markedly improve the number and quality of the trigger values that can be derived and will increase end-users’ ability to understand and implement the guidelines in a scientifically rigorous manner. 相似文献
863.
C. Singaraja S. Chidambaram P. Anandhan M. V. Prasanna C. Thivya R. Thilagavathi J. Sarathidasan 《Environment, Development and Sustainability》2014,16(3):689-721
In modern living, rapid development has created an increase in demand for groundwater. An endeavor has been made to understand the hydrogeochemical parameters to determine the utility of groundwater. This situation is severe in coastal hard rock aquifers due to the influence of salinity ingression and other anthropogenic influence. A total of 135 groundwater samples were collected from the coastal aquifer of the Tuticorin district and analyzed for major cations and anions during premonsoon (PRM) and postmonsoon (POM). The ions analyzed were used to determine the drinking, agricultural and domestic utility of groundwater. The electrical conductivity (EC) contour shows that the groundwater quality is poor along the coast. The parameters were compared with WHO (Guidelines for drinking water quality recommendations, WHO, Geneva, 2004) standard for drinking purpose. A groundwater classification method has been developed for groundwater in the area using a dynamic water quality index (WQI). On the basis of the WQI so computed, groundwater in the area has been spatially classified into “excellent,” “good,” “poor” and “very poor” to “Unsuitable” water types variation lithologywise. Corrosivity ratio and hardness were noted to be higher and found to be unsuitable in majority of the regions for domestic purpose. Higher fluoride concentration was noted in the central part of the study area represented by complex geology comprising of the hornblende biotite gneiss and charnockite. Sodium percentage (Na%), sodium absorption ratio, residual sodium carbonate, Wilcox (Classification and use of irrigation waters, US Department of Agriculture, Washington, 1955), permeability index, residual sodium bicarbonate, magnesium hazard, Kelly’s ratio and potential salinity also indicate that most of the groundwater samples are not suitable for irrigation purposes. 相似文献
864.
Elisa Oteros-Rozas Berta Martín-López José A. González Tobias Plieninger César A. López Carlos Montes 《Regional Environmental Change》2014,14(4):1269-1289
The ecosystem services framework is receiving increasing attention in the fields of policy and research. The assessment of human attitudes and perceptions regarding ecosystem services has been proposed as a promising tool for addressing complex problems associated with environmental change, particularly in the context of cultural landscapes. Transhumance is not only a farming practice responsible for shaping cultural landscapes but also an adaptive strategy based on mobility that may represent a useful approach to overcoming the growing challenges posed by accelerated environmental change. A socio-cultural valuation of ecosystem services associated with the Conquense Drove Road, one of the major transhumant networks still in use in Mediterranean Spain, was conducted via the distribution of questionnaires to 416 local residents and visitors to capture their perceptions regarding the importance of 34 ecosystem services (10 provisioning, 12 regulating, and 12 cultural) for both social and personal well-being. Overall, the ecosystem services considered to be the most important for social well-being were fire prevention, air purification and livestock. Most of the ecosystem services in question were perceived as declining, with the exception of those associated with recreation, scientific knowledge and environmental education. This study revealed that perceptions regarding the value of ecosystem services differed among respondents, depending on their age, place of origin and gender. Several methodological issues, as well as the implications of socio-cultural valuation for policy making, are also discussed here. 相似文献
865.
Grace B. Villamor Robert Gilmore Pontius Jr. Meine van Noordwijk 《Regional Environmental Change》2014,14(2):825-834
This paper examines the size and intensity of changes among five land categories during the two time intervals in a region of Indonesia that is pioneering negotiations concerning reducing emissions from deforestation and forest degradation (REDD). Maps at 1973, 1993, and 2005 indicate that land-cover change is accelerating, while carbon loss is decelerating in Jambi Province, Sumatra. Land dynamics have shifted from Forest loss during 1973–1993 to Agroforest loss during 1993–2005. Forest losses account for most reductions in aboveground carbon during the both time intervals, but Agroforest plays an increasingly important role in carbon reductions during the more recent interval. These results provide motivation for future REDD policies to count carbon changes associated with all influential land categories, such as Agroforests. 相似文献
866.
D. C. Mccune Leonard H. Weinstein Jay S. Jacobson A. E. Hitchcock 《Journal of the Air & Waste Management Association (1995)》2013,63(11):465-468
Leaves of Tendergreen bean plants exposed to atmospheric fluoride concentrations in the range 1.7 to 7.6 μg/m3 showed increased levels of enolase and catalase activity and decreased levels of pyruvate and α-ketoglutarate. Phosphoenolpyruvate carboxylase activity and oxalacetate were not affected. The leaves of Milo maize plants exposed to 5.0 μg F/m3 showed increased levels of enolase and pyruvate kinase activity and a decreased level of pyruvate. Oxalacetate and α-ketoglutarate levels were not affected. Catalase activity was increased, then decreased by IIF fumigation. The changes induced by HF were greatest six to 10 days after the start of fumigation and disappeared or decreased in magnitude during the post-fumigation period. 相似文献
867.
C. E. Barthel JR. 《Journal of the Air & Waste Management Association (1995)》2013,63(11):475-478
This is a report on Meetings of Representatives of National Air Pollution Preventions Associations to Consider the Establishment of an International Union, held in Washington, D. C, June 18–19, 1964 and Houston, Texas, June 21–22, 1964. 相似文献
868.
869.
Marvin E. Miller George C. Holzworth 《Journal of the Air & Waste Management Association (1995)》2013,63(1):46-50
An urban diffusion model, which does not require the use of an electronic computer, is presented. The main simplifying assumptions are that continuous pollutant sources are uniformly distributed over the urban area and vertical diffusion occurs until the effluent from each line source reaches the top of the mixing layer, after which the effluent is uniformly distributed through the mixing layer. After the appropriate vertical diffusion coefficient is specified, the calculated concentration is a function of source strength, linear dimension of the metropolis, mixing depth, and wind speed. The calculated concentration is interpreted either as a representative maximum concentration or, through integration, as the average concentration over the metropolitan area. When a representative pollutant concentration is known, the model may be used to determine the apparent “uniform” source strength. 相似文献
870.
C. C. Shale 《Journal of the Air & Waste Management Association (1995)》2013,63(3):159-160
Current-voltage relationships for negative corona are given for a pilot-scale electrostatic precipitator with 3-in. electrode spacing at 80°–1500°F and 35–80 psig. Direct comparison is made with the electrical characteristics for a 1-in. spacing at 1200°F over the same pressure range. Experimental results on both spacing agree well with electrostatic theory. Initial dust removal efficiencies for the pilot-scale precipitator ranged from 90 to 98% at 1460°F and 80 psig, but continuous operation was not achieved owing to excessive thermal expansion of the internal parts of the unit. 相似文献