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31.
Monica?R.?LaraEmail author David?L.?Jones Zhongxing?Chen John?T.?Lamkin Cynthia?M.?Jones 《Marine Biology》2008,153(3):235-248
Juvenile gray snapper, Lutjanus griseus, are believed to use bays and estuaries in southern Florida as nurseries before moving out to the adjoining reef tract as
adults. Using high-resolution sector field-inductively coupled plasma-mass spectrometry (SF-ICP-MS), the elemental chemistry
of the otoliths of juveniles from five nursery regions was resolved by establishing elemental “signatures” for each region.
In this study we simultaneously analyzed 32 elements including a suite of rare earth elements. A stepwise variable selection
procedure retained a subset of eight elements that contributed substantially to separating otolith samples, including two
rare earth elements; this is one of the first studies in which rare earth elements in otoliths have contributed to separation
of fish stocks. The classification success rate in assigning fishes to the correct region of origin was 82%. Resolution of
sites less than 10 km apart suggested high site fidelity in juvenile gray snapper and little mixing of water masses between
sites. The juvenile nursery signatures will be used to determine the relative contribution of different nurseries to the adult
population on an adjoining reef tract. 相似文献
32.
Patterns of mtDNA diversity in North Atlantic populations of the mussel Mytilus edulis 总被引:3,自引:3,他引:0
Patterns of (female) mitochondrial DNA diversity were investigated in the blue mussel Mytilus edulis. Mytilus edulis is a ubiquitous member of contemporary North Atlantic hard-substrate communities and well represented in studies of this
region. Mytilus edulis was surveyed in North America and Europe, as well as mid-Atlantic sites in Greenland, Iceland, and the Faroe Islands. Mitochondrial
DNA sequences revealed considerable population structure but no monophyly of haplotypes between any major regions. Coalescent
analyses suggest that migration across the Atlantic Ocean has prominently been from North American source populations and
that Greenland was colonized recently and exclusively from North America. In North America, there was support for two regional
groups along the North American coastline. Surprisingly, we also found evidence of recombination between some Mytilus edulis and Mytilus galloprovincialis female mtDNA sequences, particularly in northern Europe.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An erratum to this article can be found at 相似文献
33.
Cynthia L. Quast 《补救:环境净化治理成本、技术与工艺杂志》2001,12(1):63-75
Voluntary cleanup programs for contaminated sites have been developed in several states over the last few years. Some of the advantages of these programs include developing a collaboration between site owners and regulators, implementing cleanup standards based upon site‐specific current and future risks, and enhancing the market conditions that can lead to development of properties to their highest productive use. This article offers a case study of the first site in Iowa to proceed through the state's voluntary cleanup program, the Land Recycling Program. It offers the step‐by‐step progress toward the client's goal of a site classification requiring no further action. © 2001 John Wiley & Sons, Inc. 相似文献
34.
Reginald Blake Reza Khanbilvardi Cynthia Rosenzweig 《Journal of the American Water Resources Association》2000,36(2):279-292
ABSTRACT: It has been well established that the greenhouse gas loading of the atmosphere has been increasing since the mid 19th century. Consequently, shifts in the earth's radiative balance are expected with accompanying alterations to the earth's climate. With these anticipated, and perhaps already observable, changes in both global and regional climate, managers of regional water resources seek insight to the possible impacts climate change may have on their present and future water supplies. The types and degrees of impacts that climate change may have on New York City's water supply system were assessed in a study of a watershed at Allaben, New York. Hypothetical scenarios of future climate and climate change projections from three General Circulation Models (GCMs) were used in conjunction with the WatBal hydrological model and the Palmer Drought Severity Index (PDSI) to ascertain how runoff and soil moisture from this watershed may change in a warmer climate. For the worst case predictions, the results indicate that within the century of the 2000s, the watershed's air temperature may increase up to about 11°F, while its precipitation and runoff may decrease by about 13 and 30 percent, respectively. If this watershed is typical of the others within the New York City water supply system, the system's managers should consider implementing mitigation and adaptation strategies in preparation for the worst of these possible future conditions. 相似文献
35.
Shailaja K Johnson ME 《Journal of environmental biology / Academy of Environmental Biology, India》2007,28(2):331-332
Fluoride is a naturally occurring toxic mineral present in drinking water and causes yellowing of teeth, tooth problems etc. Fluorspar, Cryolite and Fluorapatite are the naturally occurring minerals, from which fluoride finds its path to groundwater through infiltration. In the present study two groundwater samples, Station I and Station II at Hyderabad megacity, the capital of Andhra Pradesh were investigated for one year from January 2001 to December 2001. The average fluoride values were 1.37 mg/l at Station I and 0.91 mg/l at Station II. The permissible limit given by BIS (1983) 0.6-1.2 mg/l and WHO (1984) 1.5 mg/l for fluoride in drinking water. The groundwaters at Station I exceeded the limit while at Station II it was within the limits. The study indicated that fluoride content of 0.5 mg/l is sufficient to cause yellowing of teeth and dental problems. 相似文献
36.
Leaching of nitrogen (N) after forest fertilization has the potential to pollute ground and surface water. The purpose of this study was to quantify N leaching through the primary rooting zone of N-limited Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] forests the year after fertilization (224 kg N ha(-1) as urea) and to calculate changes in the N pools of the overstory trees, understory vegetation, and soil. At six sites on production forests in the Hood Canal watershed, Washington, tension lysimeters and estimates of the soil water flux were used to quantify the mobilization and leaching of NO(3)-N, NH(4)-N, and dissolved organic nitrogen below the observed rooting depth. Soil and vegetation samples were collected before fertilization and 1 and 6 mo after fertilization. In the year after fertilization, the total leaching beyond the primary rooting zone in excess of control plots was 4.2 kg N ha(-1) (p = 0.03), which was equal to 2% of the total N applied. The peak NO(3)-N concentration that leached beyond the rooting zone of fertilized plots was 0.2 mg NO(3)-N L(-1). Six months after fertilization, 26% of the applied N was accounted for in the overstory, and 27% was accounted for in the O+A horizon of the soil. The results of this study indicate that forest fertilization can lead to small N leaching fluxes out of the primary rooting zone during the first year after urea application. 相似文献
37.
Cynthia R. A. Mahl Thiago B. Taketa Rogério A. Bataglioli Eduardo José de Arruda Marisa M. Beppu 《Journal of Polymers and the Environment》2018,26(12):4338-4349
Chitosan (Chi) beads were conjugated with three different amino acids [namely, glutamic acid (GLU), methionine (MET), and taurine (TAU)] aiming to increase the divalent copper ions uptake in aqueous media. Scanning Electron Microscopy evidenced the development of a large porous structure after amino acid functionalization, associated with the increase in a number of amino groups in the polymer backbone. X-Ray Photoelectron Spectroscopy and Fourier-Transform Infrared Spectra analyses were also employed to assess the conjugation of these three different amino acids in chitosan backbone. Adsorption experiments were conducted in a batch process, at 298 K, and kinetic data indicated a slightly better fitting for the pseudo-first-order model when compared to pseudo-second order. Intraparticle diffusion model suggested a three-step mechanism for Cu(II) adsorption kinetics, limited by the third step, the intraparticle diffusion. The isotherm data fitting to the traditional Langmuir and Freundlich models indicated a better fit for the former case. The amino acid conjugation resulted in the increase of the maximum adsorption capacity for Cu(II) from 1.30 mmol g?1 prior to amino acid conjugation to values as high as 2.31 mmol g?1, 2.40 mmol g?1 and 2.68 mmol g?1 for Chi–TAU, Chi–GLU, and Chi–MET, respectively. These results are attributed to the introduction of additional amino groups and new carboxylate and amino acid residues into the chitosan backbone, which might also be explored for amino acid demanding applications. 相似文献
38.
39.
The connectedness to nature scale: A measure of individuals’ feeling in community with nature 总被引:1,自引:0,他引:1
Five studies assessed the validity and reliability of the connectedness to nature scale (CNS), a new measure of individuals’ trait levels of feeling emotionally connected to the natural world. Data from two community and three college samples demonstrated that the CNS has good psychometric properties, correlates with related variables (the new environmental paradigm scale, identity as an environmentalist), and is uncorrelated with potential confounds (verbal ability, social desirability). This paper supports ecopsychologists’ contention that connection to nature is an important predictor of ecological behavior and subjective well-being. It also extends social psychological research on self–other overlap, perspective taking, and altruistic behavior to the overlap between self and nature. The CNS promises to be a useful empirical tool for research on the relationship between humans and the natural world. 相似文献
40.