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161.
The goal of this study was to better quantify the degree of viral contamination of tomato and cucumber in relationship to
virus type, soil type, and irrigation method. Tomatoes and cucumbers were grown in ten-gallon (37.8 L) buckets filled with
Pima clay loam or Brazito sandy loam soils. Plants were irrigated with secondary wastewater effluent using surface drip irrigation
or subsurface drip irrigation. At specified time intervals irrigation water was seeded with bacteriophages MS-2 and P22, poliovirus
type 1 (PV1), enteric adenovirus 40 (Ead 40), and hepatitis A virus. Surface drip irrigation always resulted in viral contamination
of both the above and below ground parts of both crops. The roots showed the greatest level of contamination, followed by
leaves and fruits. In contrast, with subsurface drip irrigation no viruses were detected in any of the above ground plant
surfaces. It was found that under similar soil type and irrigation method, risk of crop contamination was similar for all
of the viruses studied. It can be concluded that method of irrigation is the single most critical factor in the contamination
trend of different parts of crop plants. Plant parts can be categorized into three groups (root, stem, and leaf/fruit) based
on the risk of viral contamination from irrigation water. 相似文献
162.
Carlos Wing-Hung Lo Plato Kwong-To Yip 《Journal of Environmental Planning and Management》1999,42(3):355-374
Cross-city analysis in environmental regulation within non-democratic political systems is a neglected area. Taking policy convergence and styles of regulation as the focus, this paper has taken an initial step to compare the environmental impact assessment (EIA) regulation in Hong Kong and Shanghai. In this comparative exercise, it is identified that policy convergence occurs more explicitly in policy ideology and policy consequences, whereas divergence takes place in policy content, regulatory process and public consultation. Convergence, however, is only superficial whereas divergence is substantial. Indeed EIA systems of these two jurisdictions have displayed contrasting styles of regulation. The formal EIA system in Shanghai is dominated by the environmental agency, which regulates informal politics in the EIA process within a legal format. The informal EIA system in Hong Kong is co-ordinated by the environmental agency, which seeks active co-operation with the clients in a consultative EIA process in an informal and discretionary manner. What makes the Hong Kong system superior to the Shanghai system is the existence of institutional channels for public consultation. Within a non-democratic political setting, the EIA process in Hong Kong is more transparent and the EIA system is more accountable to the public, whereas the EIA process in Shanghai is lacking in transparency and the EIA system is under tight bureaucratic control. 相似文献
163.
Fabricio Borges Cambraia Tarcisio Abreu Saurin Carlos Torres Formoso 《Safety Science》2010,48(1):91-99
Near misses are well-known for providing a major source of useful information for safety management. They are more frequent events than accidents and their causes may potentially result in an accident under slightly different circumstances. Despite the importance of this type of feedback, there is little knowledge on the characteristics of near misses, and on the use of this information in safety management. This article proposes guidelines for identifying, analyzing and disseminating information on near misses in construction sites. In particular, it is proposed that near misses be analyzed based on four categories: (a) whether or not it was possible to track down the event; (b) the nature of each event, in terms of its physical features (e.g. falling objects); (c) whether they provided positive or negative feedback for the safety management system; and (d) risk, based on the probability and severity associated with each event. The guidelines were devised and tested while a safety management system was being developed in a healthcare building project. The monitoring of near misses was part of a safety performance measurement system. Among the main results, a dramatic increase in both the number and quality of reports stands out after the workforce was systematically encouraged to report. While in the first 4 months of the study – when the workforce was not encouraged to report – there were just 12 reports, during the subsequent 4 months – when the workforce was so encouraged – there were 110 reports, all of them being analyzed based on the four analytical categories proposed. 相似文献
164.
Alexandre H. Hirzel Gwenaëlle Le Lay Véronique Helfer Christophe Randin Antoine Guisan 《Ecological modelling》2006
Models predicting species spatial distribution are increasingly applied to wildlife management issues, emphasising the need for reliable methods to evaluate the accuracy of their predictions. As many available datasets (e.g. museums, herbariums, atlas) do not provide reliable information about species absences, several presence-only based analyses have been developed. However, methods to evaluate the accuracy of their predictions are few and have never been validated. The aim of this paper is to compare existing and new presence-only evaluators to usual presence/absence measures. 相似文献
165.
Sousa Vitor Bogas José Alexandre Real Sofia Meireles Inês 《Environmental science and pollution research international》2023,30(4):8778-8789
Environmental Science and Pollution Research - The urge to reduce greenhouse gas emissions, in particular carbon dioxide, is a global problem, not only in spatial terms but also in terms of the... 相似文献
166.
Fernández-Landero Sandra Giráldez Inmaculada Fernández-Caliani Juan Carlos 《Environmental geochemistry and health》2021,43(10):4251-4264
Environmental Geochemistry and Health - Chestnut soils developed over mineralized areas of southwestern Spain are characterized by high baseline concentrations of geogenic trace elements, notably... 相似文献
167.
Mateus Georgenes Magarotto Monica Ferreira da Costa José António Tenedório Carlos Pereira Silva 《Journal of Coastal Conservation》2016,20(1):31-42
Coastal zones around the world have experienced urban growth in the last 50 years. This landscape change brings new aspects for those zones and the environment. Real estate speculation is a decisive factor that changes landscape, with urban growth that occurs both in the extent and volume of construction. Boa Viagem (BV) beach at Recife, Northeast Brazil was just a sand bar covered by an Atlantic Forest until middle of the 1800s. Today, it has turned into a busy area of the city where residences, services and commerce co-exist in a densely packed arrangement. This work demonstrates and analyses vertical growth in BV and urban changes from 1961 to 2011. It was developed using digital image processing and visual analysis of satellite imagery and aerial photos. A GIS was created using SPRING and ArcScene, to calculate variations in area and volume creating a Volumetric Index (VI). The Minimal Mapping Area was used in sixteen census tract as samples of the area. Occupation and vertical growth were especially accentuated from 1981 to 1996 with the peak at 2011. Increases in vertical growth from shore to inland are evident in all parts of the district. This finding was confirmed by three-dimensional GIS representations of the study area and the VI during the period of this work, showing the potential of 3D GIS models for studying dense urbanization areas in coastal zones. 相似文献
168.
Ros Gloag Vanina D. Fiorini Juan Carlos Reboreda Alex Kacelnik 《Behavioral ecology and sociobiology》2014,68(4):681-689
Obligate brood parasitic birds, such as cowbirds, evade parental care duties by laying their eggs in the nests of other species. Cowbirds are assumed to avoid laying repeatedly in the same nest so as to prevent intrabrood competition between their offspring. However, because searching for host nests requires time and energy, laying more than one egg per nest might be favoured where hosts are large and can readily rear multiple parasites per brood. Such ‘repeat parasitism’ by females would have important consequences for parasite evolution because young parasites would then incur indirect fitness costs from behaving selfishly. We investigated shiny cowbird (Molothrus bonariensis) parasitism of a large host, the chalk-browed mockingbird (Mimus saturninus), in a population where over 70 % of the parasitized mockingbird nests receive multiple cowbird eggs. We assessed egg maternity directly, using cameras at nests to film the laying of individually-marked females. We also supplemented video data with evidence from egg morphology, after confirming that each female lays eggs of a consistent appearance. From 133 eggs laid, we found that less than 5 % were followed by the same female visiting the nest to lay again or to puncture eggs. Multiple eggs in mockingbird nests were instead the result of different females, with up to eight individuals parasitizing a single brood. Thus, while cowbird chicks regularly share mockingbird nests with conspecifics, these are unlikely to be their maternal siblings. Our results are consistent with shiny cowbird females following a one-egg-per-nest rule, even where hosts can rear multiple parasitic young. 相似文献
169.
Carlos Rozas Alberto de la Fuente Hugo Ulloa Peter Davies Yarko Niño 《Environmental Fluid Mechanics》2014,14(4):849-871
Lake Villarrica, located in south central Chile, has a maximum depth of 167 m and a maximum fetch of about 20 km. The lake is monomictic, with a seasonal thermocline located at a depth of approximately 20 m. Field data show the presence of basin-scale internal waves that are forced by daily winds and affected by Coriolis acceleration. A modal linear and non-linear analysis of internal waves has been used, assuming a two-layer system. The numerical simulations show good agreement with the internal wave field observations. The obtained modes were used to study the energy dissipation within the system, which is necessary to control the amplitude growth. Field data and numerical simulations identify (1) the occurrence of a horizontal mode 1 Kelvin wave, with a period of about a day that coincides with the frequency of daily winds, suggesting that this mode of the Kelvin waves is in a resonant state (subject to damping and controlled by frictional effects in the field) and (2) the presence of higher-frequency internal waves, which are excited by non-linear interactions between basin-scale internal waves. The non-linear simulation indicates that only 10 % of the dissipation rate of the Kelvin wave is because of bottom friction, while the rest 90 % represents the energy that is radiated from the Kelvin wave to other modes. Also, this study shows that modes with periods between 5 and 8 h are excited by non-linear interactions between the fundamental Kelvin wave and horizontal Poincaré-type waves. A laboratory study of the resonant interaction between a periodic forcing and the internal wave field response has also been performed, confirming the resonance for the horizontal mode 1 Kelvin wave. 相似文献
170.
Laura Serra Marc Saez Jorge Mateu Diego Varga Pablo Juan Carlos Díaz-Ávalos Håvard Rue 《Environmental and Ecological Statistics》2014,21(3):531-563
Wildfires have become one of the principal environmental problems in the Mediterranean basin. While fire plays an important role in most terrestrial plant ecosystems, the potential hazard that it represents for human lives and property has led to the application of fire exclusion policies that, in the long term, have caused severe damage, mainly due to the increase of fuel loadings in forested areas, in some forest systems. The lack of an easy solution to forest fire management highlights the importance of preventive tasks. The observed spatio-temporal pattern of wildfire occurrences may be idealized as a realization of some stochastic process. In particular, we may use a space–time point pattern approach for the analysis and inference process. We studied wildfires in Catalonia, a region in the north-east of the Iberian Peninsula, and we analyzed the spatio-temporal patterns produced by those wildfire incidences by considering the influence of covariates on trends in the intensity of wildfire locations. A total of 3,166 wildfires from 1994–2008 have been recorded. We specified spatio-temporal log-Gaussian Cox process models. Models were estimated using Bayesian inference for Gaussian Markov Random Field through the integrated nested Laplace approximation algorithm. The results of our analysis have provided statistical evidence that areas closer to humans have more human induced wildfires, areas farther have more naturally occurring wildfires. We believe the methods presented in this paper may contribute to the prevention and management of those wildfires which are not random in space or time. 相似文献