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991.
Francisco Ferreira Hugo Tente Pedro Torres Sérgio Cardoso José M. Palma-Oliveira 《Environmental monitoring and assessment》2000,65(1-2):443-450
The environmental decision-making process is related with the interpretation of data both in spatial and temporal dimensions. This paper presents a methodology that integrates the time-space framework of air quality data to infer the temporal pattern and spatial variability that could be interpreted for environmental decision purposes. Variograms that accommodate time and space lags were used for the analysis and proved to be effective. Its environmental meaning, in particular its relationship with traffic patterns is discussed. Data from air quality monitoring stations located in the central part of Lisbon were used in this study. It describes a strategy to identify the type of vehicles responsible for certain pollutant levels, particularly for nitrogen oxides, and discusses the application of new air quality European legislation to the city of Lisbon, Portugal. 相似文献
992.
T. Stuczyiński G. Demidowicz T. Deputat T. Górski S. Krasowicz J. Kuś 《Environmental monitoring and assessment》2000,61(1):133-144
This paper demonstrates the ability of Polish agriculture to adapt to predicted climate change according to GISS and GFDL scenarios. Both climate-change scenarios will significantly affect farming conditions in Poland through water deficit, shifts in planting and harvesting seasons, changes in crop yields and crop structure. Neither scenario seems to endanger the self-sufficiency of Poland as long as preventative measures are taken. Moreover, the realization of GISS creates the possibility of a surplus in production. It must be emphasized that regardless of the scenario, the adaptation of agriculture to an expected climate change cannot be handled by the farming community itself. 相似文献
993.
Alexei V. Uvarov 《Environmental monitoring and assessment》2000,60(3):337-357
Long-term charcoal production in small private charcoal kilns (CK) in Eastern Bieszczady Mts. (SE Poland) can cause local smoke contamination of the ambient forest environment. Responses of model soil systems, contaminated or not contaminated by CK smoke, to contrasting combinations of hydrothermic regimes were compared in laboratory microcosms (respiration of soil community, decomposition rate of soil organic matter and cotton stripes, herb seeds germination were studied). The majority of the obtained data show a markedly higher level of soil biological activity in the CK versus the control series. In some cases CK and control soil systems show different patterns of reactions to the tested combinations of microclimate regime. These phenomena should at least partly be attributed to the effects of CK pollution. 相似文献
994.
A.J. Wheeler I. Williams R.A. Beaumont R.S. Hamilton 《Environmental monitoring and assessment》2000,65(1-2):69-77
The personal exposure of children aged 9 – 11 years to particulate matter (PM10 and PM2.5) was carried out between January and September 1997 in the London Borough of Barnet. Personal sampling along with home, garden and classroom microenvironmental monitoring was completed for all ten children. Each child was monitored for five days during winter, spring and summer. All children completed daily time activity diaries to provide information on any potential activities that could influence their exposure to particulate matter. Each evening a household activity questionnaire was also completed by the parents. Personal Environmental Monitors were used to sample personal exposure to PM10 and PM2.5. Harvard Impactors were used for the microenvironmental sampling of both size fractions. The children's mean personal exposure concentrations for PM10 during winter, spring and summer were 72, 54 and 35 µg/m3 respectively and for PM2.5 22, 17 and 18 µg/m3 respectively. In order to determine the potential sources of particulate matter, analysis of the Teflon filters has been undertaken. The physical characteristics of the particles have been identified using Scanning Electron Microscopy. The relationships between personal exposure concentrations and the different microenvironments will be discussed. 相似文献
995.
996.
Long-Term Relationship between Phosphorus Inputs and Wetland Phosphorus Concentrations in a Northern Everglades Marsh 总被引:3,自引:0,他引:3
Assessments of long-term relationships between changes innutrient inputs and wetland nutrient concentrations can becomplicated by fluctuations in other environmental factors aswell as by problems typical of long-term monitoring data.Consequently, statistical analysisof these types of data sets requirescareful consideration of environmental covariates, potentialbiases in the monitoring design, and irregularities caused bychanges in field sampling protocols. We evaluated therelationship between anthropogenic phosphorus (P) inputs andwater-column total P (TP) concentrations in a northernEverglades marsh by statistically analyzing available datacollected from several sampling programs over the past 20 years(1978–1997). Canal inputs of agricultural runoff contributemost of the P to the marsh and have produced a zone ofenrichment within the marsh during the past few decades.Regression analyses showed that both canal and marsh TPconcentrations increased during the 1980s and then decreased inthe 1990s. However, the statistical relationship between canal Pinputs and marsh TP, while significant, generally was weakexcept for marsh locations adjacent to the canal. Strongerrelationships existed between marsh TP and hydrologic parameterssuch as marsh water depth, which is controlled by changes inweather patterns and marsh management. In particular, dryconditions during the 1980s may have contributed to observedincreases in marsh P concentrations and the movement of a P`front' further into the marsh. Higher rainfall and water depthsand agricultural best management programs initiated during the1990s have been associated with reduced P concentrations incanal waters entering the marsh. While it is anticipated thatthis reduction eventually will result in lower marsh TPconcentrations, this effect is not yet evident, possibly due tointernal loading of P from enriched marsh soils. Our findingsillustrate some of the environmental factors that can complicateattempts to develop empirical relationships between P inputs andwetland P concentrations and to use such relationships to forecast changesin marsh concentrations based on past monitoring data alone. 相似文献
997.
D.S. Lee R.D. Kingdon M.E. Jenkin A. Webster 《Environmental Modeling and Assessment》2000,5(2):105-118
In order to understand relationships between sources and receptors of atmospheric deposition, computer models must be used.
This paper describes a Lagrangian acid deposition model that represents emissions of trace species across Northern Europe.
The chemistry of sulphur dioxide, dimethyl sulphide and hydrogen sulphide is represented and the model tested against estimates
of UK wet and dry deposition. Mean UK wet and dry deposition for the period 1992–1994 was 206 and 145 ktonne S yr-1, respectively. The model predicted wet and dry deposition of 222 and 166 ktonne S yr-1, in good agreement with measurements. The model has been used to examine the sources of deposited S to the UK. For a base
year of 1992, 86% of the UK's SO2 emissions are exported. The S deposition attributable from mainland European sources was 36% of the UK total S deposition,
in good agreement with other UK models but this differs substantially from the calculations of the EMEP model. Natural sources
of S deposition from planktonic emissions of dimethyl sulphide, biological emissions of hydrogen sulphide and non-eruptive
volcanic emissions of sulphur dioxide contributed approximately 1% of the modelled UK S deposition, of which 95% originated
from dimethyl sulphide. The explicit chemical scheme for dimethyl sulphide incorporated into the model showed that 24% of
the resultant deposited S was methane sulphonic acid. Boundary conditions of the model were tested and it was found that initialisation
of sulphur dioxide and sulphate concentrations to representative ambient conditions had a very small effect. The modelled
contribution of UK and European sources to UK S deposition was approximately 40 and 60%, respectively, showing the dramatic
change arising from projected UK SO2 emissions in 2010.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
998.
Jean-Charles Hourcade Minh Ha-Duong Arnulf Grübler Richard S.J. Tol 《Integrated Assessment》2001,2(1):31-35
This communication summarizes the main findings of INASUD, an European-wide research project on integrated assessment of climate policies. The project aimed at improving the framing of climate policy analysis through the parallel use of various existing integrated assessment models. It provides a comprehensive examination of the link between uncertainty regarding damages and inertia in economic systems. Results show that the Kyoto targets and timing are consistent with the precautionary principle but offers little insurance for longer-term climate protection. Flexibility mechanisms offer potentials for cooperation with developing countries, and are necessary to tap the environmental and economic benefits of joint carbon and sulfur emissions abatement. 相似文献
999.
Bhattacharyya P Mitra A Chakrabarti K Chattopadhyay DJ Chakraborty A Kim K 《Environmental monitoring and assessment》2008,139(1-3):299-306
The present investigation deals with the limnobiotic status of Almatti reservoir from February, 2003 to January, 2005. The
study revealed that, the distribution and population density of zooplankton species depend upon the physico-chemical factors
of the environment. Statistical analysis showed that there exists a significant relation between the biological and non-biological
factors. The benthic fauna constituting the food of fish can be utilized for extensive culture operation so that the nutrients
in the reservoir are not only properly cycled but also serve as a check on further eutrophication. 相似文献
1000.
Rao PS Ansari MF Pipalatkar P Kumar A Nema P Devotta S 《Environmental monitoring and assessment》2008,137(1-3):387-392
A study on concentrations of ambient particulates viz. total suspended particulate matters (TSP), respirable suspended particulate
matter (RSPM) and polycyclic aromatic hydrocarbons (PAH) were carried out at six sites around the Asia’s largest, 12 MMTPA,
petroleum refinery in west coast of India. PAH concentrations are correlated with each other in these sites, suggesting that
they have related sources and sinks. The present article discusses the monitoring aspects such as sample collection, pretreatment
and analytical methods and compares the monitored levels for assessing the source receptor distribution pattern. The main
sources of RSPM and PAHs in urban air are automobile exhaust (CPCB, Polycyclic aromatic hydrocarbons (PAHs) in air and their effects on human health. “”, 2003; Manuel et al., Environmental Science and Technology, 13: 227–231, 2004) and industrial emissions like petroleum refinery (Vo-Dinh, Chemical analysis of polycyclic aromatic hydrocarbons, Wiley: New York, 1989; Wagrowaski and Hites, Environmental Science and Technology, 31: 279–282, 1997). Polycyclic aromatic hydrocarbons (PAH) are ubiquitous constituents of urban airborne particulate mostly generated by anthropogenic
activities (Li et al., Environmental Science and Technology, 37:1958–2965, 2003; Thorsen et al., Environmental Science and Technology, 38: 2029–2037, 2004; Ohura et al., Environmental Science and Technology, 32: 450–455, 2004) and some of them are of major health concern mainly due to their well-known carcinogenic and mutagenic properties (Soclo
et al., Marine Pollution Bulletin, 40: 387–396, 2000; Chen et al., Environment International, 28: 659–668, 2003; Larsen and Baker, Environmental Science and Technology, 32: 450–455, 2003). Limited information is available on PAHs contributions from refineries to ambient air. Hence this study would not only
create a database but also provide necessary inputs towards dose-response relationship for fixing standards. Also, since it
acts as precursor to green house gas, the data would be useful for climate change assessments. The objective of this article
is to find out the concentration of PAHs in particulate matter around petroleum refinery and compare with their concentrations
in major Indian urban centers. 相似文献