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881.
Joel Elliott Kathleen Holmes Rachel Chambers Kate Leon Peter Wimberger 《Marine Biology》2008,156(1):39-53
Mytilus galloprovincialis (Mg), the Mediterranean blue mussel, is sympatric with the native M. trossulus (Mt) throughout much of the north Pacific, likely as the result of human introduction. We investigated the distribution of the
two species and their hybrids (Mgt) in Puget Sound, Washington, to determine whether differences occur in habitat preference between the two species and hybrids.
In addition, we investigated whether there were consistent size and shape differences between the native and introduced mussels
and hybrids. Measurements of over 6,000 mussels from 30 sites, of which 1,460 were genotyped for a species-specific genetic
marker, revealed that Mg and Mgt can be found throughout Puget Sound. Mg and Mgt were larger and exhibited a greater height:length ratio than Mt. Frequencies of Mg and Mgt were higher in subtidal habitats, such as docks, than on intertidal rocks, walls or pilings. Within intertidal habitats,
Mg and Mgt were more frequent than Mt in the lower reaches of the intertidal. At slightly more than half the sites the frequency of the three genotypes accorded
with random mating expectations suggesting no consistent barriers to gene flow between species. The standardized random sampling
methods and simple morphometric identification techniques described here can be used to test whether the frequency of invasive
mussels changes over time and space in Puget Sound. 相似文献
882.
Madeleine Beekman Rosalyn S. Gloag Naïla Even Wandee Wattanachaiyingchareon Benjamin P. Oldroyd 《Behavioral ecology and sociobiology》2008,62(8):1259-1265
All honeybee species make use of the waggle dance to communicate the direction and distance to both food sources and potential
new nest sites. When foraging, all species face an identical problem: conveying information about profitable floral patches.
However, profound differences in nesting biology (some nest in cavities while others nest in the open, often on a branch or
a cliff face) may mean that species have different requirements when dancing to advertise new nest sites. In cavity nesting
species, nest sites are a precise location in the landscape: usually a small opening leading to a cavity in a hollow tree.
Dances for cavities therefore need to be as precise as possible. In contrast, when the potential nest site comprises a tree
or perhaps seven a patch of trees, precision is less necessary. Similarly, when a food patch is advertised, dances need not
be very precise, as floral patches are often large, unless they are so far away that recruits need more precise information
to be able to locate them. In this paper, we study the dance precision of the open-nesting red dwarf bee Apis florea. By comparing the precision of dances for food sources and nest sites, we show that A. florea workers dance with the same imprecision irrespective of context. This is in sharp contrast with the cavity-nesting Apis mellifera that increases the precision of its dance when advertising a potential new home. We suggest that our results are in accordance
with the hypothesis that the honeybees’ dance communication initially evolved to convey information about new nest sites and
was only later adapted for the context of foraging. 相似文献
883.
Adult Vinciguerria nimbaria are the main prey of tuna during the tuna fishing season (late autumn and winter) in the equatorial Atlantic (0–4°N, and
~15°W). V. nimbaria trophic behavior in the fishing grounds was studied in relation to hydrobiological factors to determine its role in the trophic
food web. Sampling stations spaced by 20 nautical miles were set up along a 15°W north–south transect from 4°N to 0°40S. At
each station, the temperature and vertical fluorescence profiles were recorded. Nitrate and chlorophyll a analyses were performed on water sampled at different levels in the euphotic zone. Vertical plankton hauls were carried out
at depths of 0–100 and 0–200 m using a standard WP2 net fitted with a 200-μm mesh gauze. Vinciguerria nimbaria adults were collected using a young-fish mid-water trawl net (10 × 15 m opening mouth, 10 mm cod end mesh). The weight of
the stomach contents, the stomach fullness index, the number of prey, the frequency of occurrence and the prey preponderance
were recorded for 20 fish from each haul. An oligotrophic typical tropical structure (TTS) was found between 1° and 4°N where
small zooplankton was relatively abundant above or near the thermocline. In the TTS, V. nimbaria behaved as an epipelagic fish, feeding on the dominant small prey during the daytime. In turn, it was a prey for tuna. In
the equatorial zone, where zooplankton was more abundant than in the north equatorial zone, V. nimbaria behaved as a mesopelagic fish and as an opportunistic mesozooplankton feeder. It consumed a wide range of sizes of food,
feeding on the most abundant species of zooplankton as well as the largest zooplankton species, possibly while migrating towards
the surface in the late afternoon or in the deep layer. 相似文献
884.
Hani R. El Bizri Thaís Q. Morcatty João Valsecchi Pedro Mayor Jéssica E. S. Ribeiro Carlos F. A. Vasconcelos Neto Jéssica S. Oliveira Keilla M. Furtado Urânia C. Ferreira Carlos F. S. Miranda Ciclene H. Silva Valdinei L. Lopes Gerson P. Lopes Caio C. F. Florindo Romerson C. Chagas Vincent Nijman Julia E. Fa 《Conservation biology》2020,34(2):438-448
The switch from hunting wild meat for home consumption to supplying more lucrative city markets in Amazonia can adversely affect some game species. Despite this, information on the amounts of wild meat eaten in Amazonian cities is still limited. We estimated wild meat consumption rates in 5 cities in the State of Amazonas in Brazil through 1046 door-to-door household interviews conducted from 2004 to 2012. With these data, we modeled the relationship between wild meat use and a selection of socioeconomic indices. We then scaled up our model to determine the amounts of wild meat likely to be consumed annually in the 62 urban centers in central Amazonia. A total of 80.3% of all interviewees reported consuming wild meat during an average of 29.3 (CI 11.6) days per year. Most wild meat was reported as bought in local markets (80.1%) or hunted by a family member (14.9%). Twenty-one taxa were cited as consumed, mostly mammals (71.6%), followed by reptiles (23.2%) and then birds (5.2%). The declared frequency of wild meat consumption was positively correlated with the proportion of rural population as well as with the per capita gross domestic product of the municipality (administrative divisions) where the cities were seated. We estimated that as much as 10,691 t of wild meat might be consumed annually in the 62 urban centers within central Amazonia, the equivalent of 6.49 kg per person per year. In monetary terms, this amounts to US$21.72 per person per year or US$35.1 million overall, the latter figure is comparable to fish and timber production in the region. Given this magnitude of wild meat trade in central Amazonia, it is fundamental to integrate this activity into the formal economy and actively develop policies that allow the trade of more resilient taxa and restrict trade in species sensitive to hunting. 相似文献
885.
Metal contamination of surface soils of industrial city Sialkot,Pakistan: a multivariate and GIS approach 总被引:3,自引:0,他引:3
Riffat Naseem Malik Waqar Azeem Jadoon Syed Zahoor Husain 《Environmental geochemistry and health》2010,32(3):179-191
In this study concentrations of selected metals viz., Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Na, Ni, Pb and Zn in surface soils of
Sialkot city known worldwide for tanneries and pharmaceutical industries were measured to assess the status of urban soil
pollution and to identify sources of contamination. Hierarchical cluster analysis (HACA) indicated concentrations of Mg and
Ca related to parent rock material, Cd, Co, and Pb with traffic related activities, Cr, Cu, Ni and Zn either associated with
automobiles activities or industrial pollution and Fe, K and Na related with anthropogenic activities or lithogenous materials.
Correlation analyses and principal component analysis based on factor analysis confirmed the results of HACA. Spatial distribution
maps exhibited relatively higher concentrations of Cd, Co, Cu, Ni, Pb, Cr and Zn along traffic routes in the city and streams.
The results highlighted concentration of Cd, Ni, Cr, Zn, and Pb measured in urban soil exceeded the permissible limit of surface
soils and advocated an imperative need for detailed baseline investigations of spatial distribution of heavy metals and other
contaminants for the formulation of geochemical database that should be made available to stakeholder involved in monitoring,
assessment and conservation of soil contamination for future planning and management of the Sialkot city. 相似文献
886.
In this paper, we propose a semiparametric survival model to investigate the pattern of spatial and temporal variation in
disease prevalence of chronic wasting disease (CWD) in wild deer in Wisconsin over the years 2002 and 2006. The semiparametric
survival model we suggested allows to build a more flexible model than the parametric model with fewer parametric assumptions
by modeling the baseline hazard using a Gamma process prior. Based on the proposed model, we investigate the geographical
distribution of CWD, and assess the effect of sex on disease prevalence. We use a Bayesian hierarchical framework where latent
parameters capture temporal and spatial trends in disease incidence, incorporating sex and spatially correlated random effects.
We also propose bivariate baseline hazard which change over age and time simultaneously to adopt different effects of age
and time on the baseline hazard. Inference is carried out by using MCMC simulation techniques in a fully Bayesian framework.
Our results suggest that disease has been spreaded mainly in the disease eradication zone and male deer show a significantly
higher infection probability than female deer. 相似文献
887.
Dorota Jermakowicz-Bartkowiak 《Environmental geochemistry and health》2010,32(4):317-320
Vinylbenzyl chloride/divinylbenzene gel copolymer beads have been modified using piperidine, hexamethyleneimine, piperazine,
1-(2-aminoethyl)piperazine, and N-cyclohexyl-1,3-propanediamine. These resins were then tested for the sorption of noble metal ions, namely, Re(VII), Pd(II),
Pt(IV), and Au(III), from a 0.1 M HCl solution. The effect of these resins on the sorption of other coexisting ions, such
as Cu, Ni and Fe, was also studied. Of the resins tested, resin 4 [1-(2-aminoethyl)piperazine groups] showed the highest sorption
capacity for Pt(IV) and Re(VII) from single and multicomponent solutions, with the sorption of Pt(IV) from the multicomponent
solution (Re, Au, Pd, Pt, Cu, Ni Fe) in 0.1 M HCl reaching 68 mg Pt/g. 相似文献
888.
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
889.
Jiang He Chang-Wei Lü Hong-Xi Xue Ying Liang Saruli Bai Ying Sun Li-Li Shen Na Mi Qing-Yun Fan 《Environmental geochemistry and health》2010,32(1):45-58
This paper analyses the contents and species distributions of rare earth elements (REEs) in the water-suspended particulate-sediment
system of the Baotou section of the Yellow River, China, with known anthropogenic REE input from industrial discharges. The
major forms of REEs were suspended and dissolved in the mainstream and the tributaries of the Baotou section, respectively.
The concentrations of the dissolved and suspended REEs had the same trends in the overlying water along the mainstream, which
increased from the Seqi section (site A) to the mouth of the Sidaosha River (site D), reaching a maximum value at site D,
and tending to decrease thereafter. The contents of REEs in sediment cores showed enrichment with light rare earth elements
(LREEs). The bound to carbonates and to Fe–Mn oxides are the major forms of REE in the secondary phase and the REE exhibited
LREE enrichment pattern and moderate Eu depletion in suspended particulates and surface sediments. The contents and species
distributions of REEs in the water-suspended particulate-sediment system of the Baotou section suggest that the anthropogenic
source of REEs from Baotou city have enhanced REE accumulation to the Baotou section. This information is important for predicting
possible pollution resulting from anthropogenic REE input into rivers. 相似文献
890.
Hydrogeochemical considerations about the origin of groundwater salinization in some coastal plains of Elba Island (Tuscany,Italy) 总被引:1,自引:0,他引:1
Elena Giménez-Forcada Alberto Bencini Giovanni Pranzini 《Environmental geochemistry and health》2010,32(3):243-257
Several coastal plains of the Elba Island (Marina di Campo, Portoferraio, Schiopparello, Mola, Porto Azzurro and Barbarossa
plains) in Tuscany (Italy) were studied to determine the causes of decline in groundwater quality, using major ion chemistry
to establish the causes of groundwater salinization. The study demonstrates that salinization of coastal plain alluvial aquifers
is not simply linked to seawater intrusion but is also intimately related to inflows from adjacent aquifers. Ionic ratios,
correlation graphs and distribution value maps were employed as the means to understand the hydrochemistry of the study areas.
The Mg/Cl ratio in particular can be considered a good tracer to distinguish the main salinization processes that control
groundwater chemistry. Seawater intrusion only partly determines the chemistry of some groundwaters, which generally belong
to a chloride facies where the salinity is derived principally from freshwater–seawater mixing and the participation of cation
exchange. Proceeding inland groundwater quality seems to be principally determined by the inflow of Mg, Ca-HCO3 or Ca, Na-HCO3 waters formed from the weathering of silicate minerals in adjoining aquifers. Hydrolysis of these minerals is of prime importance
in controlling groundwater chemistry in adjacent alluvial plains. The lateral recharge flows introduce water with a different
chemical composition and this variable of freshwater recharge changes the hydrochemistry as a result of mixing between two
or more waters types. This situation is further complicated when seawater and base exchange reactions participate, due to
seawater intrusion. 相似文献