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71.
Alejandro?CantareroEmail authorView authors OrcID profile Jesús?Carrasco Naranjo Fabián?Casas Francois?Mougeot Javier?Vi?uela Carlos?Alonso-Alvarez 《Die Naturwissenschaften》2018,105(7-8):45
Complex body designs, such as plumage ornaments in birds, can be described by fractal geometry. These complex patterns could have a role as visual signals during courtship and social interactions, but an empirical validation in the wild is currently lacking. Here, we investigated whether the fractal dimension (FD) of a complex plumage pattern displayed by red-legged partridges Alectoris rufa could function as a potential sexual signal. We captured wild birds early in the breeding season and tested if mated and unmated birds differed in the FD of their conspicuous melanin-based black bib. We also tested if the FD of the black bib was correlated within the pair, looking for evidence of assortative mating based on the expression of this trait. We simultaneously assessed similar effects in other ornamental traits (black bib size, white throat patch and black flank band surface, redness of the eye rings and bill). Mated birds showed higher black bib FD values than unmated ones. Mated males, but not females, also displayed a larger black bib. Moreover, the black bib FD (but not the trait size) and the white throat patch surface showed assortative mating. Finally, females with higher black bib FD showed smaller black flank band surface, suggesting a trade-off in the expression of the two melanin-pigmented plumage traits. This provides unique and novel indication for the shape complexity of a pigmented trait, here described by its fractal dimension, to be potentially under sexual selection in a wild animal. 相似文献
72.
Ronal Gainza-Carmenates J. Carlos Altamirano-Cabrera Philippe Thalmann Laurent Drouet 《Environmental Science & Policy》2010,13(1):63-71
Quantitative assessments help to highlight the main features of climate policies by better identifying their strengths and weaknesses. In this study, we develop a grading system for assessing thirteen proposals for post-2012 climate policy. We believe that these proposals contain appropriate policy instruments which will be considered for discussions about how to design the post-2012 climate agreement. Our grades are based on four criteria: environmental effectiveness, cost effectiveness, distributional considerations and institutional feasibility. We analyze the grades with two complementary methods: principal component and cluster analysis. Our results entail three policy implications. Firstly, the higher the number of policy instruments a proposal comprises, the more difficult might be its implementation. Secondly, proposals which include a meaningful effort by the U.S. tend to fail in environmental effectiveness and institutional feasibility. Thirdly, we identify that the “first best” and the “second best” approaches belong to a stable policy group, and both may be considered as suitable candidates for post-2012 climate policy. 相似文献
73.
D. James Baker Gary Richards Alan Grainger Patrick Gonzalez Sandra Brown Ruth DeFries Alexander Held Josef Kellndorfer Peter Ndunda Dennis Ojima Per-Erik Skrovseth Carlos Souza Fred Stolle 《Environmental Science & Policy》2010,13(3):249-260
International negotiations on the inclusion of land use activities into an emissions reduction system for the UN Framework Convention on Climate Change (UNFCCC) have been partially hindered by the technical challenges of measuring, reporting, and verifying greenhouse gas (GHG) emissions and the policy issues of leakage, additionality, and permanence. This paper outlines a five-part plan for estimating forest carbon stocks and emissions with the accuracy and certainty needed to support a policy for Reducing Emissions from Deforestation and forest Degradation, forest conservation, sustainable management of forests, and enhancement of forest carbon stocks (the REDD-plus framework considered at the UNFCCC COP-15) in developing countries. The plan is aimed at UNFCCC non-Annex 1 developing countries, but the principles outlined are also applicable to developed (Annex 1) countries. The parts of the plan are: (1) Expand the number of national forest carbon Measuring, Reporting, and Verification (MRV) systems with a priority on tropical developing countries; (2) Implement continuous global forest carbon assessments through the network of national systems; (3) Achieve commitments from national space agencies for the necessary satellite data; (4) Establish agreed-on standards and independent verification processes to ensure robust reporting; and (5) Enhance coordination among international and multilateral organizations. 相似文献
74.
75.
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
76.
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
77.
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
78.
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
79.
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
80.
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