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171.
Agricultural soils of two Italian maize farms were treated for five years with an industrially produced high-quality compost. Cattle manure and the usual mineral fertilizer were used for comparison purposes. The effects of the organic and mineral fertilizer treatments were studied by analyzing the compost and manure, cultured soils, and harvested material. The grain yield was also determined. Organic fertilization improved soil pH, CEC, content of organic matter and NPK. Soil respiration and N mineralization were found to be higher than in the purely mineral-treated soil. Plant K take-up was improved, whereas grain yield was not affected. It was confirmed that organic fertilization, particularly compost use, maintained and increased soil fertility. The study demonstrated the feasibility of using in loco analytical facilities to follow the entire recycling process-from waste to compost production-and the use of the final product in the field.  相似文献   
172.
Located on the northeast Brazilian coast, Olinda is one of UNESCO’s World Heritage Sites, which is economically dependent on tourism, commerce, industry, and the informal economy. Despite its environmental and socioeconomic importance, the city of Olinda (understanding the coast as part of it) has suffered several environmental and human disturbances over the last decades. This work describes the environmental and social status of Olinda’s beaches and makes recommendations concerning the development of an Integrated Coastal Management Plan for this coastal zone of the Brazilian littoral. The methodology adopted in this study is based on field campaigns (social, physical, chemical, and biological data collection), local observations, and the collection of sea contention building project data from city hall. The results showed that along the seven studied beaches, the main problems were related to the: (i) building of coastal protections, (ii) inefficient sewage disposal systems, (iii) inefficient urban management, and (iv) natural events (equinoctial spring tides and precipitation/evaporation rates). Casa Caiada beach showed the best hydrologic conditions as a consequence of its morphology and it presents facilities that attract housing and recreation investments (by private and public sectors) valuing and improving local use conditions. The obtained data showed that the studied beaches need an urgent action plan to minimize the environmental degradation of Olinda’s littoral and to promote sustainable development of the local coastal environments.  相似文献   
173.
Improvements in remote sensing technologies and the use of geographic information system (GIS), are increasingly allowing us to develop indicators that can be used to monitor and assess ecosystem condition and change at multiple scales. This paper presents global- and regional-level indicators developed by the World Resources Institute and collaborating partners using remote sensing and GIS. Presented as regional and global maps, these spatial indicators are ideal communication tools to raise awareness of the condition of the Earths ecosystems among different audiences. Global and regional spatial indicators not only inform us about the current condition of, and pressures on, ecosystems, but also about the likely capacity of the ecosystem to continue to provide goods and services to future generations. The increasing focus on integrating socio-economic and biological information with remote sensing and GIS technology can only help to further our understanding and capacity to manage ecosystems in a more sustainable manner.The author researched and wrote this paper while working for the World Resources Institute (WRI).  相似文献   
174.
Place attachment and place identity in natives and non-natives   总被引:1,自引:1,他引:1  
Place attachment is an affective bond that people establish with specific areas where they prefer to remain and where they feel comfortable and safe. Place identity, however, has been defined as a component of personal identity, a process by which, through interaction with places, people describe themselves in terms of belonging to a specific place. Most research has observed positive correlations between these variables in populations that have maintained ongoing interactions over long periods of time. This work presents two studies in which we compare place attachment to place identity in samples differentiated according to birthplace and length of residence, and the magnitude of these bonds to different places. The results of the first study revealed differences between intensity of attachment and identity depending on place of origin and place assessed. The second study found that identity and attachment tend to coincide in natives, while individuals from other places give higher scores for attachment than for identity. Results from the two studies have enabled us to consider that place attachment develops before place identity, at least in the case of the non-natives. Both studies reveal that bonds are stronger with the city than with the neighbourhood, but that attachment and identity with the island are stronger than either of them.  相似文献   
175.
The Negro River is located in the Amazon basin, the largest hydrological catchment in the world. Its water is used for drinking, domestic activities, recreation and transportation and water quality is significantly affected by anthropogenic impacts. The goals of this study were to determine the presence and concentrations of the main viral etiological agents of acute gastroenteritis, such as group A rotavirus (RVA) and genogroup II norovirus (NoV GII), and to assess the use of human adenovirus (HAdV) and JC polyomavirus (JCPyV) as viral indicators of human faecal contamination in the aquatic environment of Manaus under different hydrological scenarios. Water samples were collected along Negro River and in small streams known as igarapés. Viruses were concentrated by an organic flocculation method and detected by quantitative PCR. From 272 samples analysed, HAdV was detected in 91.9 %, followed by JCPyV (69.5 %), RVA (23.9 %) and NoV GII (7.4 %). Viral concentrations ranged from 102 to 106 GC L?1 and viruses were more likely to be detected during the flood season, with the exception of NoV GII, which was detected only during the dry season. Statistically significant differences on virus concentrations between dry and flood seasons were observed only for RVA. The HAdV data provides a useful complement to faecal indicator bacteria in the monitoring of aquatic environments. Overall results demonstrated that the hydrological cycle of the Negro River in the Amazon Basin affects the dynamics of viruses in aquatic environments and, consequently, the exposure of citizens to these waterborne pathogens.  相似文献   
176.
Gemycircularvirus (GemyCV) is a group of viruses which has been recently proposed as a new viral genus detected in fecal and environmental samples around the world. GemyCVs have been detected in human blood, brain tissue, cerebrospinal fluid, and stool sample. In the present study, we demonstrate for the first time, through molecular detection and characterization, the presence of GemyCVs in environmental samples from Brazil. Our results show a percentage of positivity ranging from 69 (25/36) to 97 % (35/36) in river water samples collected in Manaus, Amazon region, and wastewater from a wastewater treatment plant located in Rio de Janeiro, respectively, revealing GemyCVs as an important environmental contaminant.  相似文献   
177.
This article presents a systematic literature review of 109 articles (1992–2015) dealing with Local Agenda 21 processes worldwide. It analyzes two essential elements of Local Agenda 21: (1) the holistic approach of the sustainable development concept and (2) the main driving forces behind such processes. It shows that, although at the beginning, sustainability was seen as a natural extension of environmental policy work, it has been perceived over recent years as a guiding principle applied to issues of environment, economic development, and social welfare, and Local Agenda 21 is perceived as a coherent approach to sustainability planning. In addition, Local Government Strategy is the main typology followed, although it suffers from important limitations. Future studies could focus on local sustainability process outcomes. Further quantitative studies would be welcome, given the qualitative case study dominance in the field. We conclude with a research agenda to tackle theoretical, methodological, and empirical lacunae.  相似文献   
178.
Volcanic eruptions originated the Canary Islands (Spain), and today, different landscapes clearly show that active volcanism. The microbial communities present in these volcanic environments, both at high (above 70 degrees C) and moderate (25-35 degrees C) temperatures, were analyzed. Rock samples were processed using molecular techniques based on both DNA and RNA and complemented with the culture of microorganisms at a wide range of temperatures. Microorganisms detected through RNA-based molecular surveys were mostly related to mesophilic microorganisms, while representatives of hyperthermophiles were not detected. RNA decay curves at 80 degrees C resulted in half-life estimates of less than 2 min for mesophilic microorganisms, supporting a recent and continuous arrival of microorganisms to the high temperature sampled sites. This study constitutes a unique experimental approach showing a great natural potential of microorganisms to spread out to different natural environments. The implications are of great interest for the biogeography, dispersal, and potential distribution of microorganisms, and their genetic information, in natural environments.  相似文献   
179.
The southern Yucatán contains the largest expanse of seasonal tropical forests remaining in Mexico, forming an ecocline between the drier north of the peninsula and the humid Petén, Guatemala. The Calakmul Biosphere Reserve resides in the center of this region as part of the Mesoamerican Biological Corridor. The reserve's functions are examined in regard to land changes throughout the region, generated over the last 40 years by increasing settlement and the expansion and intensification of agriculture. These changes are documented from 1987/1988 to 2000, and their implications regarding the capacity of the reserve to protect the ecocline, forest habitats, and butterfly diversity are addressed. The results indicate that the current landscape matrix serves the biotic diversity of the reserve, with several looming caveats involving the loss of humid forests and the interruption of biota flow across the ecocline, and the amount and proximity of older forest patches beyond the reserve. The highly dynamic land cover changes underway in this economic frontier warrant an adaptive management approach that monitors the major changes underway in mature forest types, while the paucity of systematic ecological and environment-development studies is rectified in order to inform policy and practice.  相似文献   
180.
The combined effect of time and temperature on elemental release and speciation from a metal contaminated soil (Master Old Site, MOS) was investigated. The soil was equilibrated at 10, 28, 45, 70 and 90 degrees C for 2 days, 2 weeks, and 2 months in the laboratory. Dissolved organic carbon (DOC), total soluble elements (by ICP), and labile metals (by DPASV) were determined in the filtered (0.22 microm) supernatants. For the samples equilibrated at 90 degrees C, DOC fractions were size fractionated by filtration and centrifugation; a subsample was only centrifuged while another was also filtered through a 0.45 microm filter. Analyses of the supernatants (ICP, DPASV, DOC) were performed on all size fraction subsamples. Dissolved organic carbon (DOC) increased both with temperature and incubation time; however, metal behavior was not as uniform. In general, total soluble metal release (ICP) paralleled the behavior of DOC, increasing with both time and temperature, and confirming the importance of soil organic matter (SOM) in metal retention. Voltammetric analysis (dpasv) of Cu and Zn showed that very little of these metals remains labile in solution due, presumably, to complexation with dissolved organic matter. Labile concentrations of Cd, on the other hand, constituted a significant portion (50%) of total soluble Cd. Copper and Al increased in solution with time (up to 2 months) and temperature up to 70 degrees C; however, at 90 degrees C the soluble concentration declined sharply. The same behavior was observed after equilibration for longer periods of time (550 days) at lower temperatures (23 and 70 degrees C). While concentrations of labile Cu and total soluble Cu and Al increased in the unfiltered samples, the trend remained the same. DPASV analysis showing shifts in labile Cu complexes with temperature and time, together with the results from the unfiltered samples, lead to the hypothesis that Cu was complexing with large polymers that could form at the elevated temperature, and thus be removed from the analyzed solution. It is possible that Cu and Al released by SOM oxidation has re-sorbed or complexed to more recalcitrant organic matter or to mineral phases. Variations in the relative molecular size fractions present within the DOC pool produced by increased time and temperature may influence the element-DOC complexes present in solution and their behavior in soil environments.  相似文献   
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