Delacruzcastro3104

The main land use/land cover changes (LULCC) have been associated with population growth and energy policies in the São Paulo State, Brazil, since 1970. The LULCC can alter the behavior of trace elements in different environmental systems, with the riverbed sediments being the main reservoirs or sinks for trace elements, and thus become a valuable environmental archive on temporal changes. Thus, the main purpose of the study was to apply a multi-tracer analysis to estimate the historical evolution of pollution in riverbed sediment of a subtropical watershed, the lower course of the Piracicaba River, São Paulo, Brazil. 210Pb measurements done on river sediment core samples allowed estimating a sedimentation rate of 9 mm yr-1 between 1971 and 2001. Zn was the most abundant trace element in the sediment core, followed by Cr, Cu, Ni, Pb, Sc and Cd. The total concentrations of Cd, Cr, Ni, Sc and Pb presented practically no variations in the sediment core, with a continuous excess of ca. buy Bafilomycin A1 0.27 μg g-1 yr-1 of Cu and of ca. 0.54 μg g-1 yr-1 of Zn between 1971 and 2001. The excess of Cu and Zn was associated with labile fractions, in particular with carbonate bound to Zn and organic matter bound to Cu. The assessment of trace metal pollution indicated that most of the trace elements were of geogenic origin, except for Cu and Zn. According to the sediment quality guidelines used in Brazil, Pb showed no potential toxic effect, Cu, Cr and Zn were intermediate to Threshold Effect Level (TEL) and Probable Effect Level (PEL) and the Cd and Ni concentrations were above the PEL limits. The elemental and isotopic analysis of C and N and the C/N ratio indicated that the anthropogenic origin of POM found in the sediment core is related mainly to domestic sewage.Can intraspecific diversity functionally supersede interspecific diversity? Recent studies have established the ecological effects of intraspecific variation on a number of ecosystem dynamics including resilience and productivity and we hypothesised that they may functionally exceed those of species diversity. We focused on a coastal ecosystem dominated by two coexisting bioengineering mussel species, one of which, Perna perna, displays two distinct phylogeographic lineages. A manipulative field experiment revealed greater habitat structural complexity and a more benign microscale environment within beds of the eastern lineage than those of the western lineage or the second species (Mytilus galloprovincialis); the latter two did not differ. Similarly, while infaunal species abundance and biomass differed significantly between the two lineages of Perna, there was no such difference between Mytilus and the western Perna lineage. The evenness and diversity of associated infaunal assemblages responded differently. Diversity differed relatively weakly between species, while evenness showed a very strong difference between conspecific lineages. Our results show that variation within a species can functionally supersede diversity between species. As the two P. perna lineages have different physiological tolerances, we expect them to react differently to environmental change. Our findings indicate that predicting the ecosystem-level consequences of climate change requires an understanding of the relative strengths of within- and between-species differences in functionality.Despite increasing interest in hydrological effects on riverine ecosystems, few studies have documented the impact of hydrology on biofilm community functions, and those existing have typically focused on annual-based hydrological indices. In this study, we conducted monthly samplings during a year in five lowland streams with different flow regimes and investigated the impacts of hydrological conditions and physico-chemical variables on the trait composition of diatoms growing on artificial substrates, biomass (chlorophyll a and ash free dry weight), and biofilm community functions (biochemical processes, i.e., biofilm metabolism and nutrient uptake rates measured in the laboratory). Instead of the commonly used annual-based hydrological indices, we calculated indices for shorter periods (14 and ~28 days) of the hydrological regimes. Results of species-based variation partitioning showed that short-period hydrological indices (10.10 ± 7.18%) contributed more to explain species distribution than physico-chemistigating the effects of flow regime on biofilm community composition and functions.The interpretive utility of environmental magnetic proxies for investigating airborne particulate matter (PM) pollution impact is restricted by differences in soil composition, land cover and land use. For soil magnetic applications, land use strongly influences magnetic particle distribution down the soil profile, even in homogeneous soil environments. Here, an adaptive approach is engineered to provide accurate magnetic proxy information for pollution monitoring across different land use types. In an 81-km2 area between two industrial harbours, the irregular distribution of forests, arable lands, pasture and residential areas prevented robustly relating topsoil magnetic susceptibility data to known pollution impacts. Although normalized topsoil susceptibility values showed improved potential for deriving airborne pollution impacts, optimal results were obtained by depth-integrating magnetic susceptibility logs, revealing long-term impacts of both active and decommissioned industrial facilities. Complementing soil magnetic observations, active and passive (bio)magnetic monitoring allowed discriminating short-term pollution patterns and evaluating changes in PM impact across the study area. Hereby, active PM receptors (strawberry leaves and plastic coated cardboards (PCCs)) provided promising results, yet passive receptors allowed estimating pollution impacts more efficiently. For the latter, species-independent grass leaf sampling reflected airborne PM depositional patterns most accurately, whereas wiped anthropogenic surfaces proved too sensitive to wash-off.Governments in many developing countries, such as China, are investing a lot of human, financial and material resources to ensure that as much of municipal solid waste (MSW) as possible is collected for centralized harmless treatment and disposal. This is regarded as an effective way to alleviate the "waste siege" problem in governance caused by the continuous enormous increase in MSW quantity. Therefore, how to improve the efficiency of MSW collection service system is an important governance issue because the inputs that can be utilized to manage MSW problem are limited due to budget and resource constraints. However, studies on MSW collection efficiency in developing countries like China are under-represented in the existing literature. This paper applies a stochastic frontier analysis (SFA) approach to evaluate the efficiency of MSW collection services in 30 provinces of China from 2008 to 2017, and explore the relative importance of several factors that might influence collection efficiency. The results indicate that there exists considerable room (62.8%) to enhance efficiency since its current efficiency value is merely 0.372. With regard to influencing factors, the proportion of population aged 15-64 appears to have the greatest positive impact on efficiency, along with per capita GDP, added value of tertiary industry and education level. This paper also explores spatial variations of MSW collection efficiency across the eastern, central and western regions. These findings have policy implications and can inform the related government departments how to formulate proper policies to improve collection efficiency.In recent decades, water quality problems that impact human health, especially groundwater pollution, have been intensely studied, and this has contributed to new ideas and policies around the world such as Low Impact Development (LID) and Superfund legislation. The fundamental to many of these problems is pollutant occurrence and migration in saturated porous media, especially in groundwater. Such environments often contain contrasting zones of high and low permeability with significant differences in hydraulic conductivity (~10-4 and 10-8 m/s, respectively). High-permeability zones (HPZs) represent the primary pathways for pollutant transport in groundwater, while low-permeability zones (LPZs) are often diffusion dominated and serve as both sinks and sources (i.e., via back-diffusion) of pollutants over many decades. In this review, concepts and mechanisms of solute source depletion, contaminant accumulation, and back-diffusion in high- and low-permeability systems are presented, and new insights gained from both experimental and numerical studies are analyzed and summarized. We find that effluent monitoring and novel image analysis techniques have been adroitly used to investigate temporal and spatial evolutions of contaminant concentration; simultaneously, mathematical models are constantly upscaled to verify, optimize and extend the experimental data. However, the spatial concentration data during back-diffusion lacks diversity due to the limitations of pollutant species in studies, the microscopic mechanisms controlling pollutant transformation are poorly understood, and the impacts of these reactions on contaminant back-diffusion are rarely considered. Hence, most simulation models have not been adequately validated and are not capable of accurately predicting pollutant fate and cleanup in realistic heterogeneous aquifers. Based on these, some hypotheses and perspectives are mentioned to promote the investigation of contaminant migration in high- and low-permeability systems in groundwater.Water resource development opens up opportunities for improving smallholder farmer livelihoods in sub-Saharan Africa; however, implementation of water resource interventions to ensure sustainability hinges on the availability of sufficient quantity and quality data for monitoring, analysis and planning. Such data is often acquired through instrumentation of water resources (e.g. stream flow monitoring) or the use of hydrological models. In sub-Saharan Africa, data scarcity has limited the ability to monitor and make appropriate decisions for water resource allocation and use. Data derived from remote sensing has been considered a viable option to fill this gap; however, there is limited research in the region that evaluate the quality of the remotely sensed based datasets. This study evaluated actual evapotranspiration (AET) estimates derived from Advanced Very High Resolution Radiometer (AVHRR AET) images and Moderate Resolution Imaging Spectrometer (MOD16 AET) images using estimates from a grid-based Soil aand household income and nutrition.In life cycle assessment (LCA), temporal considerations are usually lost during the life cycle inventory calculation, resulting in an aggregated "snapshot" of potential impacts. Disregarding such temporal considerations has previously been underlined as an important source of uncertainty, but a growing number of approaches have been developed to tackle this issue. Nevertheless, their adoption by LCA practitioners is still uncommon, which raises concerns about the representativeness of current LCA results. Furthermore, a lack of consistency can be observed in the used terms for discussions on temporal considerations. The purpose of this review is thus to search for common ground and to identify the current implementation challenges while also proposing development pathways. This paper introduces a glossary of the most frequently used terms related to temporal considerations in LCA to build a common understanding of key concepts and to facilitate discussions. A review is also performed on current solutions for temporal considerations in different LCA phases (goal and scope definition, life cycle inventory analysis and life cycle impact assessment), analysing each temporal consideration for its relevant conceptual developments in LCA and its level of operationalisation.