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411.
Compost was prepared from wheat straw enriched with Rajasthan rock phosphate and Aspergillus awamori. The resulting phospho-compost along with phosphorus enriched FYM, mineral fertilizer (rock phosphate) and super phosphate were evaluated for their individual contribution in improving organic matter status, P availability, and enzymatic activities of soil under wheat crop grown in a micro plot. The results showed that total organic carbon, nitrogen, microbial biomass, and humus content (an index of organic matter status of soil) of soil was highest when farm yard manure (FYM) after its enrichment with 12.5% rock phosphate was applied. Microbial enriched phospho-compost was the product yielding highest soil available phosphorus, phosphorus uptake, urease, and cellulase activities. However, FYM amended with 25% rock phosphate resulted in the greatest enhancement of beta- glucosidase. Measured parameters indicated a sure improvement of chemical and biological activities of soil after the application of phosphorus enriched organic amendments compared to the commercial fertilizer commonly used by the Indian farmers. 相似文献
412.
Photodegradation of alphacypermethrin ((RS)-alpha cyano-3-phenoxy benzyl (1RS) cis-3-(2,2,dichlorovinyl)-2,2-dimethyl cyclopropane carboxylate) was studied as a thin film on glass surface and on black and red soil surfaces. A number of photoproducts from glass surfaces have been isolated, characterized and identified by gas chromatography-mass spectroscopy (GC-MS). However, only two of them viz. 3-phenoxy benzyl alcohol and [2,2-dichlorovinyl-3(2,2,dimethyl) cyclopropane carboxylate] could be identified from both the soil. Rate of photodegradation on glass and soil surface under UV and sunlight followed first order kinetics with significant correlation coefficients. The rate of photodegradation was greater on black than on red soil. 相似文献
413.
414.
Harish Kumar Jeswani Adisa Azapagic Philipp Schepelmann Michael Ritthoff 《Journal of Cleaner Production》2010,18(2):120-127
Life Cycle Assessment (LCA) has matured over the past decades and become part of the broader field of sustainability assessment. To strengthen LCA as a tool and eventually increase its usefulness for sustainability decision-making, it is argued that there is a need to expand the ISO LCA framework by integration and connection with other concepts and methods. This paper explores the potential options for deepening and broadening the LCA methodologies beyond the current ISO framework for improved sustainability analysis. By investigating several environmental, economic and social assessment methods, the paper suggests some options for incorporating (parts of) other methods or combining with other methods for broadening and deepening the LCA. 相似文献
415.
Koustubh M. Vaze Nisha N. Kannan L. Abhilash Vijay Kumar Sharma 《Die Naturwissenschaften》2012,99(11):967-971
Morning and evening chronotypes of sleep/wake cycles in humans are often metaphorically termed as ‘larks’ and ‘owls’. We derived Drosophila populations early and late, displaying lark- and owl-like emergence chronotypes by imposing selection for adult emergence during morning and evening hours. Preference for morning and evening emergence in these populations was accompanied by divergence in their circadian period (τ) and photic phase response curve. To test if lark- and owl-like emergence chronotypes displayed by these flies under weak environmental cycles of the laboratory would also persist in nature where several zeitgebers are present in the strongest form, we examined the emergence rhythm of early and late flies under semi-natural conditions. The early and late flies not only continued to exhibit divergent emergence waveforms under semi-natural conditions, the differences became even more prominent. However, phases of early and late emergence waveforms did not match natural morning and evening transitions, unlike that observed under laboratory conditions. These results thus provide evidence consistent with the notion that chronotypes are the result of interactions between circadian clocks and natural environmental cycles. 相似文献
416.
The need for environmental and urban planning reached a critical point in the year 2007, when one-half of the world's population
could be defined as living in cities. Urbanisation in India is also increasing at a fast rate. Urban chaos in India, emanating
from the continuous ignorance of fragile ecosystems, calls for the reshaping of existing cities as ‘eco-cities’. The ‘eco-city’—a
well-known concept in the western world—is new to the Indian context. While western connotations of eco-cities should not
be discarded outright in the context of India, core concerns vary significantly for obvious reasons. Recognising two facts—firstly,
eco-city development is altogether a fresh approach to human settlement development in India, and, secondly, the manifold
increase in the vulnerability of cities—this paper discusses documented good practice, reinforcing evolution towards the eco-city
vision. Lessons drawn from the examples cited are further deconstructed in the light of their contribution to urban risk reduction,
which provides direction to appreciating the ‘disaster-resilient eco-community’ concept in Puri, a coastal city in India.
Further, this paper attempts to unravel existing community-based practices in Puri, which are boon to the local environment
and invariably reduce disaster risk. These seemingly modest neighbourhood initiatives symbolise immense societal wealth, which
can be calibrated appropriately for reducing urban environmental risk as well. This paper also illustrates how a ‘disaster
resilient eco-community’ approach is inevitable in the present and future contexts not only to preserve sustainable development
gains but also to secure human well-being. 相似文献
417.
Microbial degradation of pyridine using Pseudomonas sp. and isolation of plasmid responsible for degradation 总被引:11,自引:0,他引:11
Mohan SV Sistla S Guru RK Prasad KK Kumar CS Ramakrishna SV Sarma PN 《Waste management (New York, N.Y.)》2003,23(2):167-171
Pseudomonas (PI2) capable of degrading pyridine was isolated from the mixed population of the activated sludge unit which was being used for treating complex effluents, the strain was characterized. Aerobic degradation of pyridine was studied with the isolated strain and the growth parameters were evaluated. Pyridine degradation was further conformed by chromatography (HPLC) analysis. The process parameters like biomass growth and dissolved oxygen consumption were monitored during pyridine degradation. In order to conform with the plasmid capability to degrade pyridine, the requisite plasmid was isolated and transferred to DH 5alpha Escherichia coli. The subsequent biodegradation studies revealed the ability of the transformed plasmid capability to degrade the pyridine. 相似文献
418.
Vijay P. Singh Prabhat K. Chowdhury 《Journal of the American Water Resources Association》1986,22(2):275-282
ABSTRACT: A comparison of 13 different methods of estimating mean areal rainfall was made on two areas in New Mexico, U.S.A., and one area in Great Britain. Daily, monthly and yearly rainfall data were utilized. All methods, in general, yielded comparable estimates, especially for yearly values. This suggested that a simpler method would be preferable for estimating mean areal rainfall in these areas. 相似文献
419.
Vijay P. Singh Kulwant Singh 《Journal of the American Water Resources Association》1985,21(6):941-952
The principle of maximum entropy (POME) was used to derive the two-parameter gamma distribution used frequently in synthesis of instantaneous or finite-period unit hydrographs. The POME yielded the minimally prejudiced gamma distribution by maximizing the entropy subject to two appropriate constraints which were the mean of real values and the mean of the logarithms of real values of the variable. It provided a unique method for parameter estimation. Experimental data were used to compare this method with the methods of moments, cumulants, maximum likelihood estimation, and least squares. 相似文献
420.
One of India's major concerns is the increasing level of land pollution largely due to the uncontrolled disposal of industrialsolid and hazardous waste. With rapid industrialization, thegeneration of industrial solid and hazardous waste has increasedappreciably and the nature of waste generated has become complex.Their impacts on the ecological bodies are noticeable. The article describes the details of studies conducted using Toxicity Characteristics Leaching Procedure, to estimate the toxicity effects of the metals viz., chromium, zinc, manganese,iron, nickel, cobalt and copper by the Zero Headspace Extractorfor the sludges generated from effluent treatment plant of steeltube, wire and plating industries on environment constituentslike groundwater, surface water and land. Toxicity Characteristics Leaching Procedure determines the mobility of organic and inorganic analytes of liquid, solid or multiphase waste from hazardous solid wastes in the form of primary and secondary extracts. These extracts are mixed in equal volumeproportion and analyzed by Direct Reading 2000 spectrophotometer.The amount of heavy metals observed during the studies in theleachates were found and the results were compared with HazardousWaste categories as per Indian Standards, TCLP regulatory limitsgiven by United States Environment Protection Agency (USEPA) andGermany Leachate Quality Standards and it was observed that theywere on higher side, needing a proper preventive concept of sludge management including handling, treatment, recovery and disposal. 相似文献