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331.
Arian D. Wallach Erick Lundgren Chelsea Batavia Michael Paul Nelson Esty Yanco Wayne L. Linklater Scott P. Carroll Danielle Celermajer Kate J. Brandis Jamie Steer Daniel Ramp 《Conservation biology》2020,34(4):997-1007
Conservation science involves the collection and analysis of data. These scientific practices emerge from values that shape who and what is counted. Currently, conservation data are filtered through a value system that considers native life the only appropriate subject of conservation concern. We examined how trends in species richness, distribution, and threats change when all wildlife count by adding so-called non-native and feral populations to the International Union for Conservation of Nature Red List and local species richness assessments. We focused on vertebrate populations with founding members taken into and out of Australia by humans (i.e., migrants). We identified 87 immigrant and 47 emigrant vertebrate species. Formal conservation accounts underestimated global ranges by an average of 30% for immigrants and 7% for emigrants; immigrations surpassed extinctions in Australia by 52 species; migrants were disproportionately threatened (33% of immigrants and 29% of emigrants were threatened or decreasing in their native ranges); and incorporating migrant populations into risk assessments reduced global threat statuses for 15 of 18 species. Australian policies defined most immigrants as pests (76%), and conservation was the most commonly stated motivation for targeting these species in killing programs (37% of immigrants). Inclusive biodiversity data open space for dialogue on the ethical and empirical assumptions underlying conservation science. 相似文献
332.
Should conservationists use lethal management to control introduced wildlife populations? Should they kill individual animals to protect endangered species? Are trade-offs that prioritize some values at the expense of others morally appropriate? These sorts of ethical questions are common in conservation. In debating such questions, conservationists often seem to presume 1 of 2 possible answers: the act in question is right or it is wrong. But morality in conservation is considerably more complex than this simple binary suggests. A robust conservation ethic requires a vocabulary that gives voice to the uncertainty and unease that arise when what seems to be the best available course of action also seems to involve a measure of wrongdoing. The philosophical literature on moral residue and moral dilemmas supplies this vocabulary. Moral dilemmas arise when one must neglect certain moral requirements to fulfill others. Under such circumstances, even the best possible decision leaves a moral residue, which is experienced emotionally as some form of grief. Examples of conservation scenarios that leave a moral residue include management of introduced rabbits in Australia, trophy hunting in Africa, and forest management trade-offs in the Pacific Northwest. Moral residue is integral to the moral experience of conservationists today, and grief is an appropriate response to many decisions conservationists must make. Article impact statement: Defensible conservation decisions may neglect moral requirements, leaving a moral residue; conservationists should respond with grief. 相似文献
333.
Shestopaloff Konstantin Xu Wei Escobar Michael D. 《Environmental and Ecological Statistics》2020,27(3):447-465
Environmental and Ecological Statistics - In this paper we present a weighted mixture distribution component counts (MDCC) approach for estimating total number of species. The proposed method... 相似文献
334.
Furlan Paloma Pfister Michael Matos Jorge Amado Conceição Schleiss Anton J. 《Environmental Fluid Mechanics》2020,20(3):579-592
Environmental Fluid Mechanics - The blockage of weirs or bridges by in-stream wood can reduce the flood discharge capacity, leading to hazardous situations. To assess the related risk, blocking... 相似文献
335.
Claire W. Varian-Ramos Jordan Karubian Vanessa Talbott Irma Tapia Michael S. Webster 《Behavioral ecology and sociobiology》2010,64(6):967-977
The repayment hypothesis posits that primary sex ratios in cooperative species should be biased towards the helping sex because
these offspring “repay” a portion of their cost through helping behavior and therefore are less expensive to produce. However,
many cooperatively breeding birds and mammals do not show the predicted bias in the primary sex ratio. Recent theoretical
work has suggested that the repayment hypothesis should only hold when females gain a large fitness advantage from the presence
of auxiliary adults in the group. When auxiliaries provide little or no fitness advantage, competition between relatives should
lead to sex ratios biased towards the dispersing (non-helping) sex. We examined the benefits auxiliaries provide to females
and corresponding offspring sex ratios in the red-backed fairy-wren (Malurus melanocephalus), a cooperatively breeding Australian bird with male auxiliary helpers. We found that auxiliaries provide little or no benefit
to female reproductive success or survival. As predicted, the population primary sex ratio was biased towards daughters, the
dispersing sex, and females with auxiliaries produced female-biased broods whereas females without auxiliaries produced unbiased
broods. Moreover, offspring sex ratios were more strongly biased toward females in years when auxiliaries were more common
in the population. These results suggest that offspring sex ratios are associated with competition among the non-dispersing
sex in this species, and also that females may use cues to assess local breeding opportunities for their offspring. 相似文献
336.
Alecos Demetriades Xiangdong Li Michael H. Ramsey Iain Thornton 《Environmental geochemistry and health》2010,32(6):529-552
In the Lavrion urban area study, Hellas, a five-step sequential extraction method was applied on samples of ‘soil’ (n = 224), affected by long-term mining and metallurgical activities, and house dust (n = 127), for the purpose of studying the potential bioaccessibility of lead and other metals to humans. In this paper, the
Pb concentrations in soil and house dust samples are discussed, together with those in rocks and children’s blood. Lead is
mainly associated with the carbonate, Fe–Mn oxides and residual fractions in soil and house dust. Considering the very low
pH of gastric fluids (1–3), a high amount of metals, present in soil (810–152,000 mg/kg Pb) and house dust (418–18,600 mg/kg Pb),
could be potentially bioaccessible. Consequently, children in the neighbourhoods with a large amount of metallurgical processing
wastes have high blood-Pb concentrations (5.98–60.49 μg/100 ml; median 17.83 μg/100 ml; n = 235). It is concluded that the Lavrion urban and sub-urban environment is extremely hazardous to human health, and the
Hellenic State authorities should urgently tackle this health-related hazard in order to improve the living conditions of
local residents. 相似文献
337.
Akshay A. Gowardhan Michael J. Brown Eric R. Pardyjak 《Environmental Fluid Mechanics》2010,10(3):311-328
This work describes and evaluates a pressure solver that has been incorporated into a fast response three-dimensional building-resolving
diagnostic wind modeling system. The solver computes the three-dimensional pressure field around buildings and on exterior
walls in terms of a coefficient of pressure by solving a simplified pressure Poisson equation (that neglects turbulence stresses
in the Navier-Stokes) for incompressible flow. The input to the solver is the three-dimensional mean wind field obtained from
a fast response empirical-diagnostic urban wind model. The present study is an evaluation of the pressure solver using wind-tunnel
data for flow normal to and at a 45° angle to an isolated cubical building. Results for the normal incident wind angle case
indicate that the model satisfactorily reproduces the general spatial patterns and the magnitude of the pressure difference
around much of the cube. Details of the flow field that are not satisfactorily predicted include the spatial distribution
of pressure on the roof and the lower half of the front side of the building and the magnitude along the sidewalls where pressures
are over predicted. The results for the 45° case show reasonable agreement between the model and experiments on the front
and the back walls, but over predict pressures on the leading edge of the rooftop. Regions with poor pressure predictions
appear to be a result of unsatisfactory mean wind modeling. 相似文献
338.
Helen S. Findlay Michael A. Kendall John I. Spicer Stephen Widdicombe 《Marine Biology》2010,157(4):725-735
Ocean acidification and global warming are occurring concomitantly, yet few studies have investigated how organisms will respond
to increases in both temperature and CO2. Intertidal microcosms were used to examine growth, shell mineralogy and survival of two intertidal barnacle post-larvae,
Semibalanus balanoides and Elminius modestus, at two temperatures (14 and 19°C) and two CO2 concentrations (380 and 1,000 ppm), fed with a mixed diatom-flagellate diet at 15,000 cells ml−1 with flow rate of 10 ml−1 min−1. Control growth rates, using operculum diameter, were 14 ± 8 μm day−1 and 6 ± 2 μm day−1 for S. balanoides and E. modestus, respectively. Subtle, but significant decreases in E. modestus growth rate were observed in high CO2 but there were no impacts on shell calcium content and survival by either elevated temperature or CO2. S. balanoides exhibited no clear alterations in growth rate but did show a large reduction in shell calcium content and survival under
elevated temperature and CO2. These results suggest that a decrease by 0.4 pH(NBS) units alone would not be sufficient to directly impact the survival of barnacles during the first month post-settlement.
However, in conjunction with a 4–5°C increase in temperature, it appears that significant changes to the biology of these
organisms will ensue. 相似文献
339.
Michael Tobler Dennis Hasselquist Henrik G. Smith Maria I. Sandell 《Behavioral ecology and sociobiology》2010,64(5):717-727
Hormone-mediated maternal effects play an important role in the formation of a differentiated phenotype. They have been shown
to influence a wide array of offspring traits, both early in life and in adulthood. One important offspring trait that is
under the influence of maternal androgens is the immune system. In birds, a growing number of studies show that yolk androgens
modulate immune function during the chick stage. However, there is a lack of knowledge regarding long-term effects of prenatal
androgens on offspring immunity. In this study, we therefore investigated the influence of prenatal testosterone (T) on several
measures of immunity in fledgling and adult zebra finches (Taeniopygia guttata). Cell-mediated immune response (towards phytohaemagglutinin, PHA) of fledglings hatching from control eggs was negatively
related to brood size, whereas there was no such association for fledglings hatching from eggs with experimentally elevated
T levels (T fledglings). Male control fledglings showed reduced mass gain compared to female control fledglings within 24 h
after the PHA injection. This pattern was reversed in T fledglings. Total antibody levels in fledglings were not affected
by egg treatment. Neither cell-mediated immunity nor total antibody levels in sexually mature zebra finches were influenced
by egg treatment. However, there was an immuno-enhancing effect of elevated egg T on both primary and secondary humoral immune
responses toward diphtheria and tetanus antigens in ca 5 and 7 month old zebra finches. In addition, the covariation between
different immune components differed between T and control offspring, suggesting that egg treatment may have altered the potential
trade-offs between different parts of the immune system. Our results suggest that prenatal androgens could be an important
factor contributing to individual variation in immune function even in adulthood. 相似文献
340.
Rodrigo W. Soria-Auza Michael Kessler Paola M. Barajas-Barbosa Marcus Lehnert Jürgen Böhner 《Ecological modelling》2010,221(8):1221-1229
The quality of climate models has largely been overlooked as a possible source of uncertainty that may affect the outcomes of species distribution models, especially in the tropics, where comparatively few climatic stations are available. We compared the geographical discrepancies and potential conservation implications of using two different climate models (Saga and Worldclim) in combination with the species modelling approach Maxent in Bolivia. We estimated ranges of selected bird and fern species biogeographically restricted to either humid montane forest of the northern Bolivian Andes or seasonal dry tropical forests (in the Andes and southern lowlands). Saga and Worldclim predicted roughly similar climate patterns of temperature that were significantly correlated. Precipitation layers of both climate models were also roughly similar, but showed important differences. Species ranges estimated with Worldclim and Saga likewise produced different results. Ranges of species endemic to humid montane forests estimated with Saga had higher AUC (Area under the curve) values than those estimated with Worldclim, which for example predicted the occurrence of humid montane forest bird species near Lake Titicaca, an area that is clearly unsuitable for these species. Likewise, Worldclim overpredicted the occurrence of fern and bird species in the lowlands of the Chapare region and well south of the Andean Elbow, where more seasonal biomes occur. By contrast, Saga predictions were coherent with the known distribution of humid montane forests in the northern Bolivian Andes. Estimated ranges of species endemic to seasonal dry tropical forests predicted with Saga and Worldclim were not statistically different in most cases. However, detailed comparisons revealed that Saga was able to distinguish fragments of seasonal dry tropical forests in rain-shadow valleys of the northern Bolivian Andes, whereas Worldclim was not. These differences highlight the neglected influence of climate layers on modelling results and the importance of using the most accurate climate data available when modelling species distributions. 相似文献