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Impacts of atmospheric pollution on the plant communities of British acid grasslands Полный текст
2011
Payne, Richard J. | Stevens, Carly J. | Dise, Nancy B. | Gowing, David J. | Pilkington, Michael G. | Phoenix, Gareth K. | Emmett, Bridget A. | Ashmore, Michael R.
Impacts of atmospheric pollution on the plant communities of British acid grasslands Полный текст
2011
Payne, Richard J. | Stevens, Carly J. | Dise, Nancy B. | Gowing, David J. | Pilkington, Michael G. | Phoenix, Gareth K. | Emmett, Bridget A. | Ashmore, Michael R.
Air pollutants are recognised as important agents of ecosystem change but few studies consider the effects of multiple pollutants and their interactions. Here we use ordination, constrained cluster analysis and indicator value analyses to identify potential environmental controls on species composition, ecological groupings and indicator species in a gradient study of UK acid grasslands. The community composition of these grasslands is related to climate, grazing, ozone exposure and nitrogen deposition, with evidence for an interaction between the ecological impacts of base cation and nitrogen deposition. Ozone is a key agent in species compositional change but is not associated with a reduction in species richness or diversity indices, showing the subtly different drivers on these two aspects of ecosystem degradation. Our results demonstrate the effects of multiple interacting pollutants, which may collectively have a greater impact than any individual agent.
Показать больше [+] Меньше [-]Impacts of atmospheric pollution on the plant communities of British acid grasslands Полный текст
2013 | 2011
Payne, Richard | Stevens, Carly J | Dise, Nancy B | Gowing, David J | Pilkington, Michael G | Phoenix, Gareth K | Emmett, Bridget A | Ashmore, Michael R | Biological and Environmental Sciences | Lancaster University | Manchester Metropolitan University | The Open University | University of Sheffield | University of Sheffield | Centre for Ecology & Hydrology (CEH) | University of York
Air pollutants are recognised as important agents of ecosystem change but few studies consider the effects of multiple pollutants and their interactions. Here we use ordination, constrained cluster analysis and indicator value analyses to identify potential environmental controls on species composition, ecological groupings and indicator species in a gradient study of UK acid grasslands. The community composition of these grasslands is related to climate, grazing, ozone exposure and nitrogen deposition, with evidence for an interaction between the ecological impacts of base cation and nitrogen deposition. Ozone is a key agent in species compositional change but is not associated with a reduction in species richness or diversity indices, showing the subtly different drivers on these two aspects of ecosystem degradation. Our results demonstrate the effects of multiple interacting pollutants, which may collectively have a greater impact than any individual agent.
Показать больше [+] Меньше [-]Distributions of polyhalogenated compounds in Hudson River (New York, USA) fish in relation to human uses along the river Полный текст
2011
Skinner, Lawrence C.
PCBs (as Aroclor concentrations) have been extensively examined in fish along the Hudson River, but other xenobiotic chemicals in fish have had limited assessment. This study determined concentrations and congener distributions of polybrominated diphenyl ethers (PBDEs), polybrominated and polychlorinated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs and PCDD/Fs), and polychlorinated biphenyls (PCBs) in smallmouth bass and striped bass taken from a 385km reach of the Hudson River. Concentrations of PBDEs and PCBs in smallmouth bass, and PCBs in striped bass, were positively related to human uses of the compounds in the basin. Generally low levels of PCDD/Fs were found. One striped bass, however, contained elevated 2,3,7,8-TCDD, indicating exposure to a known source in the adjacent Newark Bay-Passaic River basin. PBDDs were generally below detection. PBDFs were present in four of 18 smallmouth bass, but were not detected in striped bass. Dioxin-like PCBs contribute most to 2,3,7,8-TCDD toxic equivalents in 29 of 30 samples.
Показать больше [+] Меньше [-]Nitrogen critical loads using biodiversity-related critical limits Полный текст
2011
Posch, Maximilian | Aherne, Julian | Hettelingh, Jean-Paul
Critical loads are widely used in the effects-based assessment of emission reduction policies. While the impacts of acidification have diminished, there is increasing concern regarding the effects of nitrogen deposition on terrestrial ecosystems. In this context much attention has been focussed on empirical critical loads as well as simulations with linked geochemistry–vegetation models. Surprisingly little attention has been paid to adapt the widely used simple mass balance approach. This approach has the well-established benefit of easy regional applicability, while incorporating specified critical chemical criteria to protect specified receptors. As plant occurrence/biodiversity is related to both the nutrient and acidity status of an ecosystem, a single abiotic factor (chemical criterion) is not sufficient. Rather than an upper limit for deposition (i.e., critical load), linked nutrient nitrogen and acidity chemical criteria for plant occurrence result in an ‘optimal’ nitrogen and sulphur deposition envelope.
Показать больше [+] Меньше [-]Carbon savings resulting from the cooling effect of green areas: A case study in Beijing Полный текст
2011
Lin, Wenqi | Wu, Tinghai | Zhang, Chengguo | Yu, Ting
Green areas cool the climate of a city, reduce the energy consumption caused by the urban heat island (UHI) effect, and bring along carbon savings. However, the calculation of carbon savings due to the cooling effect of green areas is still not well understood. We have used a Landsat Enhanced Thematic Mapper Plus (ETM+) image of Beijing, to identify the cooled areas, compute the possible energy used to maintain the temperature differences between cooled areas and their surrounding heated areas, and calculate the carbon savings owing to the avoidance of energy use. Results show that a total amount of 14315.37 tons carbon savings was achieved in the study area and the amount was related to the biomass, the size and the shape of green areas. These results demonstrate the importance of carbon savings resulting from green areas' cooling effect.
Показать больше [+] Меньше [-]Incidence of polybrominated diphenyl ethers in central air conditioner filter dust from a new office building Полный текст
2011
Ni, Hong-Gang | Cao, Shan-Ping | Chang, Wen-Jing | Zeng, Hui
This study examined polybrominated diphenyl ethers (PBDEs) in central air conditioner filter (CACF) dust from a new office building in Shenzhen, China. Human exposure to PBDE via dust inhalation and ingestion were also estimated. PBDEs level in CACF dust was lower than those in the other countries and regions. Approximately 0.671 pg/kg bw/day PM₂.₅ (Particulate Matter up to 2.5 μm in size) bounded Σ₁₅PBDEs can be inhaled deep into the lungs and 4.123 pg/kg bw/day PM₁₀ (Particulate Matter up to 10 μm in size) bounded Σ₁₅PBDEs tend to be deposited in the upper parts of the respiratory system. The average total intake of Σ₁₅PBDEs via dust inhalation and ingestion for adults reached ∼141 pg/kg bw/day in this building. This value was far below the reference dose (RfD) recommended by United States Environmental Protection Agency. Human exposure to PBDEs via dust inhalation and ingestion in the new building is less than the old ones.
Показать больше [+] Меньше [-]Urban and rural mortality rates during heat waves in Berlin and Brandenburg, Germany Полный текст
2011
Gabriel, Katharina M.A. | Endlicher, Wilfried R.
In large cities such as Berlin, human mortality rates increase during intense heat waves. Analysis of relevant data from north-eastern Germany revealed that, during the heat waves that occurred between 1990 and 2006, health risks were higher for older people in both rural and urban areas, but that, during the two main heat waves within that 17-year period of time, the highest mortality rates were from the city of Berlin, and in particular from its most densely built-up districts. Adaptation measures will need to be developed, particularly within urban areas, in order to cope with the expected future intensification of heat waves due to global climate change.
Показать больше [+] Меньше [-]Analyzing trophic transfer of heavy metals for food webs in the newly-formed wetlands of the Yellow River Delta, China Полный текст
2011
Cui, Baoshan | Zhang, Qijun | Zhang, Kejiang | Liu, Xinhui | Zhang, Honggang
Nine heavy metals sampled from water, sediments, and aquatic organisms in the newly-formed wetlands of the Yellow River Delta (YRD) of China were analyzed to evaluate their concentrations and trophic transfer in food webs. The stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopes were used to investigate trophic interactions. Results show that most of heavy metals detected in water and sediments are lower than that in Yangtze River Delta and Pearl River Delta. The longest food web is approximately 4 with the highest trophic level of birds. The difference of heavy metal concentrations between endangered Saunders’s Gull and other three kinds of protected birds is not obvious. Cd, Zn, and Hg were identified to have an increase with the trophic level (TL), while As, Cr, Cu, Mn, Ni and Pb show an opposite trend, however, the biomagnification of the selected nine heavy metals in the food webs is not significant.
Показать больше [+] Меньше [-]The effects of the insecticide lambda-Cyhalothrin on the earthworm Eisenia fetida under experimental conditions of tropical and temperate regions Полный текст
2011
García, Marcos | Scheffczyk, Adam | Garcia, Terezinha | Römbke, Jörg
Plant Protection Products can affect soil organisms and thus might have negative impacts on soil functions. Little research has been performed on their impact on tropical soils. Therefore, the effects of the insecticide lambda-Cyhalothrin on earthworms were evaluated in acute and chronic laboratory tests modified for tropical conditions, i.e. at selected temperatures (20 and 28°C) and with two strains (temperate and tropical) of the compost worm Eisenia fetida. The insecticide was spiked in two natural soils, in OECD artificial soil and a newly developed tropical artificial soil. The effects of lambda-Cyhalothrin did rarely vary in the same soil at tropical (LC50: 68.5–229mg a.i./kg dry weight (DW); EC50: 54.2–60.2mg a.i./kg DW) and temperate (LC50: 99.8–140mg a.i./kg DW; EC50: 37.4–44.5mg a.i./kg DW) temperatures. In tests with tropical soils and high temperature, effect values differed by up to a factor of ten.
Показать больше [+] Меньше [-]Relationship between ²¹⁰Pbₑₓ activity and sedimentary organic carbon in sediments of 3 Chinese lakes Полный текст
2011
Xu, Libin | Wu, Fengchang | Wan, Guojiang | Liao, Haiqing | Zhao, Xiaoli | Xing, Baoshan
This report demonstrates that organic matter was an important factor in lake sediment ²¹⁰Pbₑₓ dating. Sediment cores from lakes in central and western China with different-trophic levels were collected, and the ²¹⁰Pbₑₓ activity and total organic carbon (TOC) were measured. The Rock-Eval pyrolysis technique was used to deconvolute TOC into free hydrocarbons (S1), thermally less-stable macromolecular organic matter (S2a), kerogen (S2b), and residual carbon (RC). The results show significant correlations between TOC and ²¹⁰Pbₑₓ, particularly between S2a and ²¹⁰Pbₑₓ, in all the sediment cores. This indicated that the algal-derived organic component S2a may play the most important role in controlling the distribution of ²¹⁰Pbₑₓ. Scavenging by algal-derived organic matter may be the main mechanism. As chronology is the key to the understanding of pollution reconstruction and early diagenesis in sediments, more attention should be paid to the influence of organic matter on ²¹⁰Pbₑₓ.
Показать больше [+] Меньше [-]Assessing the diurnal variability of pharmaceutical and personal care products in a full-scale activated sludge plant Полный текст
2011
Salgado, R. | Marques, R. | Noronha, J.P. | Mexia, J.T. | Carvalho, G. | Oehmen, A. | Reis, M.A.M.
An intensive sampling campaign has been carried out in a municipal wastewater treatment plant (WWTP) to assess the dynamics of the influent pharmaceutical active compounds (PhAC) and musks. The mass loadings of these compounds in wastewater influents displayed contrasting diurnal variations depending on the compound. The musks and some groups of PhACs tended to follow a similar diurnal trend as compared to macropollutants, while the majority of PhACs followed either the opposite trend or no repeatable trend. The total musk loading to the WWTP was 0.74±0.25gd⁻¹, whereas the total PhAC mass loading was 84.7±63.8gd⁻¹. Unlike the PhACs, the musks displayed a high repeatability from one sampling day to the next. The range of PhAC loadings in the influent to WWTPs can vary several orders of magnitude from one day or week to the next, representing a challenge in obtaining data for steady-state modelling purposes.
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