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961.
Marian Leimbach Nico Bauer Lavinia Baumstark Ottmar Edenhofer 《Environmental Modeling and Assessment》2010,15(3):155-173
Within this paper, we present the novel hybrid model REMIND-R and its application in a climate policy context based on the
EU target to avoid a warming of the Earth’s atmosphere by more than 2°C compared to the pre-industrial level. This paper aims
to identify necessary long-term changes in the energy system and the magnitude of costs to attain such a climate protection
target under different designs of the post-2012 climate policy regime. The regional specification of mitigation costs is analyzed
in the context of globalization where regions are linked by global markets for emission permits, goods, and several resources.
From simulation experiments with REMIND-R, it turns out that quite different strategies of restructuring the energy system
are pursued by the regions. Furthermore, it is demonstrated that the variance of mitigation costs is higher across regions
than across policy regimes. First-order impacts, in particular, reduced rents from trade in fossil resources, prevail regardless
of the design of the policy regime. 相似文献
962.
When agricultural lands are no longer used for agriculture and allowed to recover its natural vegetation, soil organic carbon
can accumulate in the soil. Measurements of soil organic carbon and aggregate stability changes under various forms of land
use are needed for the development of sustainable systems. Therefore, comparison of soil samples taken from both agricultural
and nearby area close to land-mined fields where no agricultural practices have been done since 1956 can be a good approach
to evaluate the effects of tillage and agriculture on soil quality. The objective of this study was to compare tillage, cropping
and no tillage effects on some soil-quality parameters. Four different locations along the Turkey–Syria border were selected
to determine effects of tillage and cropping on soil quality. Each location was evaluated separately because of different
soil type and treatments. Comparisons were made between non-tilled and non-cropped fallow since 1956 and adjacent restricted
lands that were tilled about every 2 years but not planted (T) or adjacent lands tilled and planted with wheat and lentil
(P). Three samples were taken from the depths of 0–20 and 20–40 cm each site. Soil organic carbon (SOC), pH ,electrical conductivity,
water soluble Ca++, Mg++, CO3-2{\rm CO}_{3}^{-2} and HCO3-{\rm HCO}_{3}^{-}, extractable potassium (K+) and sodium (Na+), soil texture, ammonium (NH4+{\rm NH}_{4}^{+}–N) and nitrate (NO3–N), extractable phosphorous and soil aggregate stability were determined. While the SOC contents of continuous tillage without
cropping and continuous tillage and cropping were 2.2 and 11.6 g kg−1, respectively, it was 30 g kg−1 in non-tilled and non-planted site. Tillage of soil without the input of any plant material resulted in loss of carbon from
the soil in all sites. Soil extractable NO3−N contents of non-tilled and non-cropped sites were greatest among all treatments. Agricultural practices increased phosphorus
and potassium contents in the soil profile. P2O5 contents of planted soils were approximately 20 to 39 times greater than those of non-tilled and non-cropped soils at different
sites. FTIR spectra showed that never tilled sites had greater phenol, carboxylic acid, amide, aromatic compounds, polysaccharide
and carbohydrates than other treatments. 相似文献
963.
Monavari SM Omrani GA Karbassi A Raof FF 《Environmental monitoring and assessment》2012,184(4):1841-1846
Environment problems associated with the generation of waste are part of societal changes where households play an important
role. These societal changes influence the size, structure and characteristic of given households. For the effective planning
of solid-waste handling infrastructure, it is essential to know the quantity of waste generation and its composition. This
paper presents the findings of a study carried out in an urban municipal area in Iran to determine the household solid-waste
generation rate and waste composition based on field surveys and to determine the related socioeconomic parameters. The dependent
variables were waste generation and composition, and independent variables were family size, family employment, age, number
of room and education. Over 400 sample households were selected for the study using a stratified random sampling methodology
and from five different socioeconomic groups. Waste collected from all groups of households were segregated and weighted.
Waste generation rate was 5.4 kg/household/day. Household solid waste comprised of ten categories of wastes and with the largest
component (76.9%). The generation and composition of household solid waste were correlated with family size, education level
and households income. This paper adequately suggests new insights concerning the role of socioeconomic parameters in affecting
the generation of household waste. 相似文献
964.
Bai S Srikantaswamy S Krishnanandan V Naik OP 《Environmental monitoring and assessment》2012,184(1):239-249
Urban wastewater treatment leads to the generation of large quantities of biosolids. Accumulation of biosolids is a problem
of environmental relevance due to the existence of heavy metals in the biosolids. Determination of total metal in biosolid
provides information relating pollution levels. Determination of their mobilization capacity and behaviour in the environment
is an important task. An experimental approach commonly used for studying the mobility, transport and bioavailability of metal
in biosolids is the use of selective sequential extraction procedure. In the present study an attempt has been made to study
the heavy metal properties in biosolid samples collected from urban wastewater treatment plants located at Mysore, Karnataka.
Few heavy metals selected for the present study are cadmium, chromium, copper, iron, nickel and zinc. The concentration of
these metals in biosolids and their partition in different fractions are studied. The speciation of metals based on the sequential
extraction scheme was carried out. The concentration of heavy metals is lower than that established by European legislation.
The residual fraction has the maximum percentage of heavy metals whereas, only a small fraction of heavy metals (Fe, Zn and
Cd) are extracted in the most soluble fractions, exchangeable and carbonate fractions. 相似文献
965.
Concentration of heavy metals (Cd, Ni, Zn, Fe, Cu, Mn, Pb, Cr, Hg and As) in the waters of River Yamuna and in the soil of
agricultural fields along its course in Delhi are reported from 13 sites, spread through the Delhi stretch of Yamuna, starting
from the Wazirabad barrage till the Okhla barrage. Varying concentration of heavy metals was found. Peaks were observed in
samples collected downstream of Wazirabad and Okhla barrage, indicating the anthropogenic nature of the contamination. The
Wazirabad section of the river receives wastewater from Najafgarh and its supplementary drains, whereas the Shahdara drain
releases its pollution load upstream of the Okhla barrage. Average heavy metal concentration at different locations in the
river water varied in the order of Fe>Cr>Mn>Zn>Pb>Cu>Ni>Hg>As>Cd. The river basin soil shows higher level of contamination
with lesser variation than the water samples among sampling locations, thereby suggesting deposition over long periods of
time through the processes of adsorption and absorption. The average heavy metal concentration at different locations in soil
varied in the order of Fe>Mn>Zn>Cr>Pb>Ni>Hg>Cu>As>Cd. 相似文献
966.
de-la-Ossa-Carretero JA Del-Pilar-Ruso Y Giménez-Casalduero F Sánchez-Lizaso JL 《Environmental monitoring and assessment》2012,184(4):2133-2149
Physicochemical characteristics of sediment and benthic communities were studied in the proximity of seven sewage outfalls
with differences in flow and wastewater treatment in the Western Mediterranean Sea. Redox potential was the only abiotic parameter
which showed a pattern related with distance to outfalls, whereas granulometry, percentage of organic matter, metal concentrations
or pH did not show changes related with outfall presence. Benthic community analysis proved to be the most suitable monitoring
tool. The results showed that the highest impacted stations corresponded with those closest to outfall with the highest flow
and only pre-treatment, whilst a decrease of this tendency was detected in the locations where secondary treatment takes place.
Meta-analysis showed a decrease of amphipods and tanaids abundance as well as redox potential, as the indicators with the
clearest response to sewage presence. 相似文献
967.
Both the net primary productivity (NPP) and the normalized difference vegetation index (NDVI) are commonly used as indicators
to characterize vegetation vigor, and NDVI has been used as a surrogate estimator of NPP in some cases. To evaluate the reliability
of such surrogation, here we examined the quantitative difference between NPP and NDVI in their outcomes of vegetation vigor
assessment at a landscape scale. Using Landsat ETM+ data and a process model, the Boreal Ecosystem Productivity Simulator,
NPP distribution was mapped at a resolution of 90 m, and total NDVI during the growing season was calculated in Heihe River
Basin, Northwest China in 2002. The results from a comparison between the NPP and NDVI classification maps show that there
existed a substantial difference in terms of both area and spatial distribution between the assessment outcomes of these two
indicators, despite that they are strongly correlated. The degree of difference can be influenced by assessment schemes, as
well as the type of vegetation and ecozone. Overall, NDVI is not a good surrogate of NPP as the indicators of vegetation vigor
assessment in the study area. Nonetheless, NDVI could serve as a fairish surrogate indicator under the condition that the
target region has low vegetation cover and the assessment has relatively coarse classification schemes (i.e., the class number
is small). It is suggested that the use of NPP and NDVI should be carefully selected in landscape assessment. Their differences
need to be further evaluated across geographic areas and biomes. 相似文献
968.
Karakaya and Sultansuyu Dam Lakes, located in the eastern part of Turkey, are important water sources, both for irrigation
and fishery. The main goal of the study was to investigate water qualities of dam lakes using a set of biomarkers in the fish
Cyprinus carpio. For this aim, field sample and laboratory-acclimated fish were compared to identify changes in selected biomarkers. The
activities of ethoxyresorufin-O-deethylase, glutathione S-transferase, glutathione reductase, and carboxylesterase were determined in liver samples. Also, plasma and liver lactate
dehydrogenase, aspartate aminotransferase, and alanine aminotransferase activities were assayed. Brain acetylcholinesterase
and carboxylesterase activities were also determined. The hepatosomatic index and condition factors were calculated. Plasma
vitellogenin assays were evaluated for the presence of xenoestrogen. Physicochemical values of water samples showed the existence
of eutrophication risk, and also, some chemicals in both lakes were determined to be over tolerable limits. The comparisons
of samples from both dam lake and laboratory-acclimated fish showed that the lakes may be at risk of pollution by some xenobiotics,
namely xenoestrogens and acetylcholinesterase-inhibiting agents. 相似文献
969.
The groundwater level represents a critical factor to evaluate hillside landslides. A monitoring system upon the real-time
prediction platform with online analytical functions is important to forecast the groundwater level due to instantaneously
monitored data when the heavy precipitation raises the groundwater level under the hillslope and causes instability. This
study is to design the backend of an environmental monitoring system with efficient algorithms for machine learning and knowledge
bank for the groundwater level fluctuation prediction. A Web-based platform upon the model-view controller-based architecture
is established with technology of Web services and engineering data warehouse to support online analytical process and feedback
risk assessment parameters for real-time prediction. The proposed system incorporates models of hydrological computation,
machine learning, Web services, and online prediction to satisfy varieties of risk assessment requirements and approaches
of hazard prevention. The rainfall data monitored from the potential landslide area at Lu-Shan, Nantou and Li-Shan, Taichung,
in Taiwan, are applied to examine the system design. 相似文献
970.
Agunbiade FO Olu-Owolabi BI Adebowale KO 《Environmental monitoring and assessment》2012,184(1):89-102
The accumulation patterns of ten metals in tissues of plant, Eichornia crassipes, and fishes, Hydrocynus forskahlii and Oreochromis mossambicus, were modeled with simple fuzzy classification (SFC) to assess toxic effects of anthropogenic activities on the coastal biota.
The plant sample was separated into root, stem, and leaves and the fishes into bones, internal tissues, and muscles. They
were analyzed for As, Cd, Cr, Cu, Ni, Pb, V, Fe, Mn, and Zn after wet oxidation of their dried samples. The results were converted
into membership functions of five accumulation classes and aggregated with SFC. The classification results showed that there
was no metal accumulation in the plant parts while the fishes were classified into low accumulation category. The internal
tissues of the fishes had higher metal accumulation than the other parts. Generally, Fe and Mn had highest concentrations
in the biota but are natural to the area and may not constitute significant risk. Cr had the highest transfer and accumulation
from the coastal water into the aquatic lives and may be indicative of risk prone system being a toxic metal. Metal contaminations
in the zone had not significantly accumulated in the biota making them less prone to risk associated with metal accumulation. 相似文献