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141.
Susana García-Alonso Rosa María Pérez-Pastor María Luisa Sevillano-Castaño 《Environmental science and pollution research international》1999,6(3):147-150
The focus of this study was to characterize the concentration levels of selected PCBs and compare them to compiled data in
order to contribute to the international database. The sampling site is located in the outskirts of Madrid and can be considered
an open urban area. 32 samples of air were taken from February 1998 to June 1998 by using a high volume air sampler. Glass
fiber filters and polyurethane foam (PUF) were used to collect the paniculate and gas phase material, respectively.
PUF plugs were Soxhlet extracted and filters were ultrasonically extracted by using pesticide-grade hexane and dichloromethane,
respectively. The cleanup procedure was carried out on a florisil column with hexane and hexane/dichloromethane as elution
solvents.
GC/MS in a selected ion monitoring mode was used for quantification and 29 selected PCBs congeners were analyzed. 相似文献
142.
Lucas Ferrante Augusto Getirana Fabricio Beggiato Baccaro Jochen Schöngart Ana Cristina Monteiro Leonel Renato Gaiga Michel Varajão Garey Philip Martin Fearnside 《Conservation biology》2023,37(3):e14033
Given the speed at which humans are changing the climate, species with high degrees of endemism may not have time to avoid extinction through adaptation. We investigated through teleconnection analysis the origin of rainfall that determines the phylogenetic diversity of rainforest frogs and the effects of microclimate differences in shaping the morphological traits of isolated populations (which contribute to greater phylogenetic diversity and speciation). We also investigated through teleconnection analysis how deforestation in Amazonia can affect ecosystem services that are fundamental to maintaining the climate of the Atlantic rainforest biodiversity hotspot. Seasonal winds known as flying rivers carry water vapor from Amazonia to the Atlantic Forest, and the breaking of this ecosystem service could lead Atlantic Forest species to population decline and extinction in the short term. Our results suggest that the selection of morphological traits that shape Atlantic Forest frog diversity and their population dynamics are influenced by the Amazonian flying rivers. Our results also suggest that the increases of temperature anomalies in the Atlantic Ocean due to global warming and in the Amazon forest due to deforestation are already breaking this cycle and threaten the biodiversity of the Atlantic Forest hotspot. 相似文献
143.
Mining activities are compatible with other activities in space and time if they are developed together and adapted to each other. If permits are required for two projects that are not considered to be compatible, the authorities will be forced to decide which one has prevalence. In the event of conflict or dispute, it is always preferable to attempt to seek compatibility between projects rather than waste time, effort and money on contesting the prevalence decision, as costly and lengthy lawsuits will only delay the development of both projects, with the resulting loss of business opportunities. In this article, technical solutions designed to achieve mining compatibility with other projects are described in terms of benefits and synergies for the projects and benefits for the government that avoid complex decisions and proceedings and optimize revenues. 相似文献
144.
Spatial Relationships of Levees and Wetland Systems within Floodplains of the Wabash Basin,USA
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Ryan R. Morrison Erin Bray Fernando Nardi Antonio Annis Quan Dong 《Journal of the American Water Resources Association》2018,54(4):934-948
Given the unique biogeochemical, physical, and hydrologic services provided by floodplain wetlands, proper management of river systems should include an understanding of how floodplain modifications influence wetland ecosystems. The construction of levees can reduce river–floodplain connectivity, yet it is unclear how levees affect wetlands within floodplains, let alone the cumulative impacts within an entire watershed. This paper explores spatial relationships between levee and floodplain wetland systems in the Wabash Basin, United States. We used a hydrogeomorphic floodplain delineation technique to map floodplain extents and identify wetlands that may be hydrologically connected to river networks. We then spatially examined the relationship between levee presence, wetland area, and other river network attributes within discrete subbasins. Our results show that cumulative wetland area is relatively constant in subbasins that contain levees, regardless of maximum stream order within the subbasin. In subbasins that do not contain levees, cumulative wetland area increases with maximum stream order. However, we found that wetland distributions around levees can be complex, and further studies on the influence of levees on wetland habitat may need to consider finer resolution spatial scales. 相似文献
145.
Omar D. Cardona Mario G. Ordaz Mabel C. Marulanda Martha L. Carreño Alex H. Barbat 《Disasters》2010,34(4):1064-1083
The Disaster Deficit Index (DDI) measures macroeconomic and financial risk in a country according to possible catastrophic scenario events. Extreme disasters can generate financial deficit due to sudden and elevated need of resources to restore affected inventories. The DDI captures the relationship between the economic loss that a country could experience when a catastrophic event occurs and the availability of funds to address the situation. The proposed model utilises the procedures of the insurance industry in establishing probable losses, based on critical impacts during a given period of exposure; for economic resilience, the model allows one to calculate the country's financial ability to cope with a critical impact. There are limitations and costs associated with access to resources that one must consider as feasible values according to the country's macroeconomic and financial conditions. This paper presents the DDI model and the results of its application to 19 countries of the Americas and aims to guide governmental decision‐making in disaster risk reduction. 相似文献
146.
Environmental Fluid Mechanics - 相似文献
147.
Salas-Zapata Walter Posada-Castaño Anny Mejía-Durango Diana 《The Environmentalist》2021,41(4):487-500
Environment Systems and Decisions - Natural resources are a type of good whose individual utility maximization is not desirable, as it could lead to their depletion. This problem, raised several... 相似文献
148.
149.
Joana?MadureiraEmail author Inês?Paciência Jo?o?Rufo André?Moreira Eduardo?de?Oliveira Fernandes Alcides?Pereira 《Environmental geochemistry and health》2016,38(2):523-533
Radon is a radioactive gas, abundant in granitic areas, such as in the city of Porto at the north-east of Portugal. This gas is a recognized carcinogenic agent, being appointed by the World Health Organization as the leading cause of lung cancer after smoking. The aim of this preliminary survey was to determine indoor radon concentrations in public primary schools, to analyse the main factors influencing their indoor concentration levels and to estimate the effective dose in students and teachers in primary schools. Radon concentrations were measured in 45 classrooms from 13 public primary schools located in Porto, using CR-39 passive radon detectors for about 2-month period. In all schools, radon concentrations ranged from 56 to 889 Bq/m3 (mean = 197 Bq/m3). The results showed that the limit of 100 Bq/m3 established by WHO IAQ guidelines was exceeded in 92 % of the measurements, as well as 8 % of the measurements exceeded the limit of 400 Bq/m3 established by the national legislation. Moreover, the mean annual effective dose was calculated as 1.25 mSv/y (ranging between 0.58 and 3.07 mSv/y), which is below the action level (3–10 mSv). The considerable variability of radon concentration observed between and within floors indicates a need to monitor concentrations in several rooms for each floor. A single radon detector for each room can be used, provided that the measurement error is considerably lower than variability of radon concentration between rooms. The results of the present survey will provide useful baseline data for adopting safety measures and dealing effectively with radiation emergencies. In particular, radon remediation techniques should be used in buildings located in the highest radon risk areas of Portugal. The results obtained in the current study concerning radon levels and their variations will be useful to optimize the design of future research surveys. 相似文献
150.