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161.
Sludge generated in intensively managed tilapia fingerling breeding ponds near the Itaparica Dam in the semi-arid Brazilian northeastern region was tested as a soil conditioner to produce lettuce in an effort to mitigate the present environmental impact of the deposition of this sludge, thereby giving it a productive destiny. A greenhouse experiment was performed by mixing the sludge with a Haplic Planosol topsoil, a characteristic soil of the region, so that the sludge corresponded to 0, 25, 50, 75, and 100% of the mixture (substrate). The experiment was set up as a randomized block design with five blocks, each with three pots (5-kg substrate per pot) of the five sludge proportion treatments. One lettuce plant was transplanted into each pot, maintained under greenhouse conditions, and harvested 35 days after transplanting. Sludge, soil, and the substrates were evaluated for nutrient concentration and physical characteristics. Green and dry weights, stem diameter, and nitrogen, phosphorus, and potassium concentrations in the aboveground parts of the lettuce plants were determined. Sludge incorporation into the substrate improved its chemical and physical characteristics. The lettuce plants grew best in the substrate with 75% sludge, increasing its biomass production by 50% and more than doubling its nitrogen uptake.  相似文献   
162.
The hunting of wild animals remains a common activity in various parts of the world, especially in rural communities with poor socioeconomic conditions. To investigate patterns of mammal hunting, this study adopted a rural community located in semiarid Brazil as a model to test whether variables such as perceived abundance, activity period (day or night) and animal biomass could influence the consumption potential of mammal taxa. For this study, a checklist/interview technique using 32 photographs of mammals recorded in the region and two photographs of species that did not occur in the region, which acted as “control” species, was used, in addition to other visual stimuli and free lists. All species presented in the photographs, with the exception of the “control” species, were recognized as occurring in the region. Fourteen species were cited as being those most hunted locally. The species cited as most hunted had an average perceived abundance higher than the group of the least-hunted species. However, there was no significant relationship between hunting of a species and its locally perceived abundance. No significant difference in hunting pressure between diurnal and nocturnal species was found, nor was a relationship between animal biomass and hunting pressure observed. Our findings suggest that perceived abundance is an important factor for choosing a resource fauna, but other factors such as intended use, meat flavor and vulnerability to hunting, among others, may influence the potential use of a species.  相似文献   
163.
Although bottom ash (BA) [or mixtures of bottom and fly ash (FA)] from clean biomass fuels is currently used as liming agent, additive for compost, and fertilizer on agricultural and forest soils in certain European countries, in several other countries most of the ashes are currently disposed in landfills. This is due to both a lack of a proper classification of the materials and of regulatory barriers.Chemical characterization including analysis of an array of potentially toxic elements (PTEs) proved that over 100,000 tons of BA currently landfilled every year in Portugal actually complied with legal limits for PTEs for soil fertilizers applied in other countries. Pot experiments were conducted, testing three dosages of BA and FA (1, 2.5, and 5%, in weight) in three mining soils with different properties. Additions of ash materials to soils led to an increase in the pore water pH relative to control pots (0% of ash added) and had a clear impact on DOC and on the solubilization of both macro- and micronutrients (notably Cu).The results from the case study using BA and FA from a Portuguese biomass thermal power plant demonstrate that it is imperative to further develop a regulatory framework to alleviate technological and environmental barriers for biomass ash utilization as raw material for fertilizers and/or soil liming agent, in accordance with the goals of the circular economy. A more harmonized view on how to assess the merits and risks of the re-use of these materials is also needed.  相似文献   
164.
In our study, we aimed to investigate the influence of landscape patterns on the diversity of birds in four urban parks. The parks are located in a region that has a high value of regional biodiversity and is also highly urbanized (Jundiai, state of São Paulo [SP], in Southeastern Brazil). Using a set of aerial photos, the surrounding landscape was divided into two regions (rings) and corresponding landscape metrics were calculated. The presence of bird species was recorded monthly over a one‐year period and classified according to selected ecological criteria. The land cover of the areas surrounding each park was primarily buildings and residences. Bird diversity was significantly correlated with the presence/proximity of water bodies. We state that the potential of the parks to harbor bird species is not negligible. Managing the area surrounding a park to increase the percentage of forested area and the size of forest fragments is as crucial as managing the core park area, especially for improving its attractiveness for new bird species.  相似文献   
165.
The intent of this research is to investigate how the customers of a technological control laboratory for civil construction materials perceived the quality of the services delivered by the lab, specifically in regard to the service of concrete compression testing. The popular SERVQUAL scale, a multidimensional instrument used to capture customer expectations and perceptions, was used as a model for the application of a survey. Exploratory factor analyses were employed to evaluate customers’ perceptions and experiences of service quality in regard to the dimensions and accompanying attributes of the SERVQUAL scale. Twenty attributes, which were grouped within five dimensions (Reliability, Assurance, Tangibles, Responsiveness, and Empathy), were identified, explaining 80.417% of the variance between customer expectations and perceptions and characterizing these dimensions on a modified SERVQUAL scale. Analysis of the results allowed us to identify discrepancies in perceived service quality compared with customers’ expectations. Most of the identified gaps between expectations and perceptions resulted in negative values.  相似文献   
166.
Journal of Material Cycles and Waste Management - The use of food waste (FW) for the production of biofuels and value-added compounds is growing worldwide. However, the significant chemical...  相似文献   
167.
Journal of Material Cycles and Waste Management - Waste water contaminated with inorganic mercury is considered a serious environmental problem, mainly due to the hazardous effects this contaminant...  相似文献   
168.
Climate change, overfishing, and other anthropogenic drivers are forcing marine resource users and decision makers to adapt—often rapidly. In this article we introduce the concept of pathways to rapid adaptation to crisis events to bring attention to the double-edged role that institutions play in simultaneously enabling and constraining swift responses to emerging crises. To develop this concept, we draw on empirical evidence from a case study of the iconic Maine lobster (Homarus americanus) industry. In the Gulf of Maine, the availability of Atlantic herring (Clupea harengus) stock, a key source of bait in the Maine lobster industry, declined sharply. We investigate the patterns of bait use in the fishery over an 18-year period (2002–2019) and how the lobster industry was able to abruptly adapt to the decline of locally-sourced herring in 2019 that came to be called the bait crisis. We found that adaptation strategies to the crisis were diverse, largely uncoordinated, and imperfectly aligned, but ultimately led to a system-level shift towards a more diverse and globalized bait supply. This shift was enabled by existing institutions and hastened an evolution in the bait system that was already underway, as opposed to leading to system transformation. We suggest that further attention to raceways may be useful in understanding how and, in particular, why marine resource users and coastal communities adapt in particular ways in the face of shocks and crises.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01617-8.  相似文献   
169.
Rapid economic growth, increasing population and change in living standards contribute to increasing the generation rate of municipal solid waste (MSW) in Denizli city, like other Turkish cities. The improper and poor MSW management system (old system) in Denizli caused environmental problems originating from the uncontrolled release of methane and leachate. In addition, the disposal of recyclable materials in unsanitary landfills is responsible for the consumption and destruction of natural sources. This paper presents a general overview of old and new MSW management practices in Denizli. Detailed data on MSW management practices including collection, transportation, disposal and recycling have been presented. The amount of solid waste generated in Denizli over the last decade has increased steadily over the years, from 108,500 tons in 1995 to 179,495 tons in 2006. The average MSW generation rate was found to be 1.23kg/day per capita. The major constituent of MSW in Denizli is food waste, but the percentage of recyclable waste has increased significantly recently. Except for metal wastes, the percentages of recyclable waste materials in Denizli are higher than in all neighborhood cities. The objective of this study is to compare the old and new MSW management systems in Denizli city. The MSW management system has been changed entirely last five years. A dumpsite was closed and a sanitary landfill with a composting facility was constructed. In addition, source separated collection has been carried out since 2002. The quantity of recyclable waste collected increased from 195 to 1549 tons. The amount of recyclable waste will continue to be increased by expanding the source separation collection system to all the districts of the city and preventing scavenging. Thus, revenue from recyclable waste ($7227 in 2006) is expected to increase. In addition, the capacity of the composting facility will be increased. Most importantly, information to increase public participation and awareness in municipal recovery programs has to be provided.  相似文献   
170.
The purpose of this study was to biomonitor metropolitan areas of Porto Alegre (Brazil) for PAHs associated with atmospheric particles and check their effects on the DNA of the land mollusk Helix aspersa. The sampling sites are located in an urban area with heavy traffic: (i) Canoas, (ii) Sapucaia do Sul, and (iii) FIERGS/Porto Alegre. The samples were collected during a continuous period of 24 hours during 15 days using Stacked Filter Units (SFU) on polycarbonate filters (two separated size fractions: PM10-2.5 and PM<2.5). The concentrations of 16 major PAHs were determined according to EPA. Comet assay on H. aspersa hemolymph cells was chosen for genotoxicity evaluation. This evaluation shows that, in general, the smaller PM-size fractions (PM<2.5) have the highest genotoxicity and contain higher concentrations of extractable organic matter. In addition, associations between chemical characteristics and PM carcinogenicity tend to be stronger for the smaller PM-size fractions.  相似文献   
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