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21.
Verma Madan L. Sukriti Dhanya B. S. Saini Raj Das Anamika Varma Rajender S. 《Environmental Chemistry Letters》2022,20(3):2189-2212
Environmental Chemistry Letters - Biosensors are gaining interest in biomedical and environmental sciences. In particular, graphene-based biosensors are promising due to the unique properties of... 相似文献
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Kant PC Bhadraray S Purakayastha TJ Jain V Pal M Datta SC 《Environmental pollution (Barking, Essex : 1987)》2007,147(1):273-281
Study on active and labile carbon-pools can serve as a clue for soil organic carbon dynamics on exposure to elevated level of CO2. Therefore, an experimental study was conducted in a Typic Haplustept in sub-tropical semi-arid India with wheat grown in open top chambers at ambient (370 micromol mol-1) and elevated (600 micromol mol-1) concentrations of atmospheric CO2. Elevated atmospheric CO2 caused increase in yield and carbon uptake by all plant parts, and their preferential partitioning to root. Increases in fresh root weight, volume and length have also been observed. Relative contribution of medium-sized root to total root length increased at the expense of very fine roots at elevated CO2 level. All active carbon-fractions gained due to elevated atmospheric CO2 concentration, and the order followed their relative labilities. All the C-pools have recorded a significant increase over initial status, and are expected to impart short-to-medium-term effect on soil carbon sequestration. 相似文献
24.
Pujari PR Nanoti M Nitnaware VC Khare LA Thacker NP Kelkar PS 《Environmental monitoring and assessment》2007,134(1-3):271-278
On-site sanitation is increasingly adopted in urban cities in India. The adoption of On-site sanitation system puts the groundwater
resources in the vicinity of the system at a greater risk. Microbial contaminants as well as chemical contaminants like Chloride
and Nitrate are generated from human waste. These contaminants travel through the medium and ultimately get in contact with
the groundwater. Hence, the groundwater sources are vulnerable to nitrate contamination near the On-site sanitation systems.
The present study indicates significant Nitrate and Chloride contamination in samples collected close to On-site sanitation
systems. The recommended limit set by the Bureau of Indian standards (BIS) limit of 45 mg/l for Nitrate concentration is also
exceeded in few samples. The study indicates that Bacterial as well as Nitrate contamination is more in Monsoon as compared
to Summer. 相似文献
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GEORGINA M. MACE NIGEL J. COLLAR KEVIN J. GASTON CRAIG HILTON‐TAYLOR H. RESIT AKÇAKAYA NIGEL LEADER‐WILLIAMS E.J. MILNER‐GULLAND SIMON N. STUART 《Conservation biology》2008,22(6):1424-1442
Abstract: The International Union for Conservation of Nature (IUCN) Red List of Threatened Species was increasingly used during the 1980s to assess the conservation status of species for policy and planning purposes. This use stimulated the development of a new set of quantitative criteria for listing species in the categories of threat: critically endangered, endangered, and vulnerable. These criteria, which were intended to be applicable to all species except microorganisms, were part of a broader system for classifying threatened species and were fully implemented by IUCN in 2000. The system and the criteria have been widely used by conservation practitioners and scientists and now underpin one indicator being used to assess the Convention on Biological Diversity 2010 biodiversity target. We describe the process and the technical background to the IUCN Red List system. The criteria refer to fundamental biological processes underlying population decline and extinction. But given major differences between species, the threatening processes affecting them, and the paucity of knowledge relating to most species, the IUCN system had to be both broad and flexible to be applicable to the majority of described species. The system was designed to measure the symptoms of extinction risk, and uses 5 independent criteria relating to aspects of population loss and decline of range size. A species is assigned to a threat category if it meets the quantitative threshold for at least one criterion. The criteria and the accompanying rules and guidelines used by IUCN are intended to increase the consistency, transparency, and validity of its categorization system, but it necessitates some compromises that affect the applicability of the system and the species lists that result. In particular, choices were made over the assessment of uncertainty, poorly known species, depleted species, population decline, restricted ranges, and rarity; all of these affect the way red lists should be viewed and used. Processes related to priority setting and the development of national red lists need to take account of some assumptions in the formulation of the criteria. 相似文献
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Singh Laishram Kanta Jha Madan Kumar Chowdary V. M. 《Environmental science and pollution research international》2021,28(2):1734-1751
Environmental Science and Pollution Research - The assessment of rainwater-harvesting demand (RWHD) map and the identification of appropriate priority-based locations for rainwater-harvesting (RWH)... 相似文献
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Presence of pesticide residues was studied in rain water during 2002 employing multi residue analysis method by gas liquid
chromatography equipped with ECD and NPD detectors and capillary columns. The presence of pesticide residues in surface aquatic
system triggered the investigation of the presence of pesticides in rain water. A total of 13 pesticides were detected in
rain water samples. Among the different groups of pesticides, organochlorines were present in the range of 0.041–7.060 ppb
with maximum concentration of p,p’-DDT up to 7.060 μg l−1. Synthetic pyrethroids were present ranging from 0.100 to 1.000 μg l−1 and organophosphates in the range of 0.050–4.000 μg l−1 showing maximum contamination with cypermethrin (1.000 μg l−1) and monocrotophos (4.000 μg l−1) of the respective groups. Almost 80% samples showed the residues above MRL of 0.5 ppb fixed for multi residues and on the
basis of single pesticide, 16–50% samples contained residues above the MRL value of 0.1 ppb. 相似文献
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Twelve samples each of soil and ground water were collected from paddy-wheat, paddy-cotton, sugarcane fields and tube wells
from same or near by fields around Hisar, Haryana, India during 2002–2003 to monitor pesticide residues. Residues were estimated
by GC-ECD and GC-NPD systems equipped with capillary columns for organochlorine, synthetic pyrethroid and organophosphate
insecticides. In soil, HCH (0.002–0.051 μg g−1), DDT (0.001–0.066 μg g−1), endosulfan (0.002–0.039 μg g−1) and chlordane (0.0002–0.019 μg g−1) among organochlorines, cypermethrin (0.001–0.035 μg g−1) and fenvalerate (0.001–0.022 μg g−1) among synthetic pyrethroids and chlorpyriphos (0.002–0.172 μg g−1), malathion (0.002–0.008 μg g−1), quinalphos (0.001–0.010 μg g−1) among organophosphates were detected. Dominant contaminants were DDT, cypermethrin and chlorpyriphos from the respective
groups. In water samples, HCH, DDT, endosulfan and cypermethrin residues were observed frequently. Only chlorpyriphos among
organophosphates was detected in 10 samples. On consideration of tube well water for drinking purpose, about 80% samples were
found to contain residues above the regulatory limits. 相似文献
29.
Kumari B Kumar R Madan VK Singh R Singh J Kathpal TS 《Environmental monitoring and assessment》2003,87(3):311-318
Monitoring of 80 winter vegetable samples during 1997–1998 for pesticidal contamination was carried out on GC-ECD and GC-NPD systems with capillary columns following multiresidueanalytical technique. The tested samples were found 100%contaminated with low but measurable amounts of pesticideresidues. Among the four major chemical groups, residue levels oforganophosphorous insecticides were highest followed bycarbamates, synthetic pyrethroids and organochlorines. About 32%of the samples showed contamination with organophosphorous andcarbamate insecticides above their respective MRL values. On thebasis of observations made in these studies, it is suggested thatmore extensive monitoring studies covering all vegetable cropsfrom different agro-climatic regions of the state be carried outto know exact level of pesticidal contamination, which may serveas basis for future policy on chemical use. 相似文献
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Mussoorie, a hill resort in the Garhwal Himalaya reveals the changing trends and impacts of tourist activity on its environment. This study was carried out during 1993–1994 and it showed that while Mussoorie had a permanent residential population of 25400 during the winter months, in the peak tourist season of May and June the population exceeded 200000 per month. Because of this huge influx of tourists the demand for lodges/hotels and other related infra-structure and super-structure facilities and amenities in the area was enormous, and it imposed a great stress on the natural environment.The data collected showed that from 1958 to 1988 the number of tourists had increased gradually but that from 1989 tourism in the town escalated following the political disturbances in the Kashmir Valley. The main purpose of the tourism was recreation (80%). It was recorded that the greatest number (60%) of the tourists were middle aged, 53% of the tourists worked in professional services. The majority of the tourists preferred to use the indigenous hotels and about 96% of the tourists used a private vehicle rather than public transport.The installation of modern tourist related facilities and infra-structure has led to the aesthetic degradation of the landscape. Tourist facility development is often disorderly and scattered. To reduce the traffic to Mussoorie town it is suggested that some nearby places like Dhanolti and Park estate should be developed for tourism. 相似文献