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71.
The long-term Biological Monitoring and Abatement Program (BMAP) has always needed to collect and retain high-quality data on which to base its assessments of ecological status of streams and their recovery after remediation. Its formal quality assurance, data processing, and data management components all contribute to meeting this need. The Quality Assurance Program comprehensively addresses requirements from various institutions, funders, and regulators, and includes a data management component. Centralized data management began a few years into the program when an existing relational database was adapted and extended to handle biological data. The database??s main data tables and several key reference tables are described. One of the most important related activities supporting long-term analyses was the establishing of standards for sampling site names, taxonomic identification, flagging, and other components. The implemented relational database supports the transmittal of data to the Oak Ridge Environmental Information System (OREIS) as the permanent repository. We also discuss some limitations to our implementation. Some types of program data were not easily accommodated in the central systems, and many possible data-sharing and integration options are not easily accessible to investigators. From our experience we offer data management advice to other biologically oriented long-term environmental sampling and analysis programs. 相似文献
72.
Angelika Brandt 《Marine Biology》1992,113(3):415-423
An analysis of the horizontal and the vertical zonation of the Antarctic Isopoda, combined with knowledge of the geological history of Antarctica and isopod phylogeny, revealed that the isopod family Serolidae and subfamily Arcturinae are likely to have evolved from ancestors that inhabited a cold-temperate Gondwanian province. Antarctic species of other families, such as the Munnopsidae, Nannoniscidae, Desmosomatidae and Ischnomesidae, are likely to have evolved from deep-sea ancestors. It is deduced that emigration of South Patagonian species into the Southern Ocean, although possible, probably did not occur very often. Evolutionary phenomena such as continental-drift vicariance, radiation of species on the continental shelf of Antarctica, and active migration, including submergence and emergence mechanisms are discussed. 相似文献
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Connectivity of wood thrush breeding,wintering, and migration sites based on range‐wide tracking
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Calandra Q. Stanley Emily A. McKinnon Kevin C. Fraser Maggie P. Macpherson Garth Casbourn Lyle Friesen Peter P. Marra Colin Studds T. Brandt Ryder Nora E. Diggs Bridget J. M. Stutchbury 《Conservation biology》2015,29(1):164-174
Many migratory animals are experiencing rapid population declines, but migration data with the geographic scope and resolution to quantify the complex network of movements between breeding and nonbreeding regions are often lacking. Determining the most frequently used migration routes and nonbreeding regions for a species is critical for understanding population dynamics and making effective conservation decisions. We tracked the migration of individual Wood Thrushes (Hylocichla mustelina) (n = 102) from across their range with light‐level geolocators and, for the first time, quantified migration routes and wintering regions for distinct breeding populations. We identified regional and species‐level migratory connectivity networks for this declining songbird by combining our tracking results with range‐wide breeding abundance estimates and forest cover data. More than 50% of the species occupied the eastern wintering range (Honduras to Costa Rica), a region that includes only one‐third of all wintering habitat and that is undergoing intensive deforestation. We estimated that half of all Wood Thrushes in North America migrate south through Florida in fall, whereas in spring approximately 73% funnel northward through a narrow span along the central U.S. Gulf Coast (88–93°W). Identifying migratory networks is a critical step for conservation of songbirds and we demonstrated with Wood Thrushes how it can highlight conservation hotspots for regional populations and species as a whole. Conectividad de Sitios de Reproducción, Invierno y Migración del Zorzal con Base en Rastreo de Cobertura Amplia 相似文献
76.
Precision-cut tissue slices of the anterior kidney from Atlantic cod (Gadus morhua) were prepared with a Krumdieck tissue slicer and exposed to 2-(2-chlorophenyl)-2-(4-chloro-(14C)phenyl)-1,1-dichlorethane (o,p(')-[14C]DDD) in vitro. Microautoradiography revealed irreversible o,p(')-DDD-derived binding confined to the glucocorticoid producing interrenal cells (adrenocortical analogues). This cell-selective binding was confirmed by means of autoradiography at different levels of resolution on Atlantic cod administered o,p(')-[14C]DDD intragastrically. The results provide evidence for a site-specific metabolic activation and irreversible binding of o,p(')-DDD in the interrenal cells, which, in turn, may modify glucocorticoid homeostasis. 相似文献
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Patel KS Shrivas K Brandt R Jakubowski N Corns W Hoffmann P 《Environmental geochemistry and health》2005,27(2):131-145
Arsenic contamination in the environment (i.e. surface, well and tube-well water, soil, sediment and rice samples) of central
India (i.e. Ambagarh Chauki, Chhattisgarh) is reported. The concentration of the total arsenic in the samples i.e. water (n=64), soil (n=30), sediment (n=27) and rice grain (n=10) were ranged from 15 to 825 μg L−1, 9 to 390 mg kg−1, 19 to 489 mg kg−1 and 0.018 to 0.446 mg kg−1, respectively. In all type of waters, the arsenic levels exceeded the permissible limit, 10 μg L−1. The most toxic and mobile inorganic species i.e. As(III) and As(V) are predominantly present in water of this region. The
soils have relatively higher contents of arsenic and other elements i.e. Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu,
Zn, As, Ga, Zr, Sn, Sb, Pb and U. The mean arsenic contents in soil of this region are much higher than in arsenic soil of
West Bengal and Bangladesh. The lowest level of arsenic in the soil of this region is 3.7 mg kg−1 with median value of 9.5 mg kg−1. The arsenic contents in the sediments are at least 2-folds higher than in the soil. The sources of arsenic contamination
in the soil of this region are expected from the rock weathering as well as the atmospheric deposition. The environmental
samples i.e. water, soil dust, food, etc. are expected the major exposure for the arsenic contamination. The most of people
living in this region are suffering with arsenic borne diseases (i.e. melanosis, keratosis, skin cancer, etc.). 相似文献
79.
Iguanian lizards perform conspicuous species-typical push-up displays, which are used in territory advertisement, threat, and courtship contexts. Subtle individually distinctive differences in push-up characteristics have been suggested to play a role in the recognition of social partners. However, if the structure of push-ups is responsive to changing physiological states then their capacity to promote recognition may be limited. The current study evaluated whether the push-ups performed while in an experimentally imposed state of fatigue by male side-blotched lizards (Uta stansburiana), retain the individually distinctive characteristics apparent in rested lizards. We found repeatable among-individual differences in the duration and the relative height of push-up components. Repeatability values did not change consistently between the rested and fatigued conditions, nor when both conditions were pooled, indicating that these push-up characteristics do not change with fatigue. Similarly, discriminant functions that were generated using push-ups from one state assigned push-ups performed in an alternate state to the correct individuals. Furthermore, when analyzed independently of individual identity, the values of display parameters examined in the current study did not change significantly between states, and discriminant function analysis could not reliably classify push-ups to the correct state. Taken together the results show that individually distinctive push-up characteristics are robust to effects of fatigue, consistent with their suggested role in social recognition. In the future, video playback experiments can test whether lizards utilize the signature-like characteristics of push-ups to discriminate among individuals.Communicated by T. Czeschlik 相似文献
80.
R. L. Schmoyeri J. J. Beauchamp C. C. Brandt F. O. Hoffman Jr 《Environmental and Ecological Statistics》1996,3(1):81-97
A frequent assumption in environmental risk assessment is that the underlying distribution of an analyte concentration is lognormal. However, the distribution of a random variable whose log has a t-distribution has infinite mean. Because of the proximity of the standard normal and t-distribution, this suggests that a distribution such as the gamma or truncated normal, with smaller right tail probabilities, might make a better statistical model for mean estimation than the lognormal. In order to assess the effect of departures from lognormality on lognormal-based statistics, we simulated complete lognormal, truncated normal, and gamma data for various sample sizes and coefficients of variation. In these cases, departures from lognormality were not easily detected with the Shapiro-Wilk test. Various lognormal-based estimates and tests were compared with alternate methods based on the ordinary sample mean and standard error. The examples were also considered in the presence of random left censoring with the mean and standard error of the product limit estimate replacing the ordinary sample mean and standard error. The results suggest that in the estimation of or tests about a mean, if the assumption of lognormality is at all suspect, then lognormal-based approaches may not be as good as the alternative methods. 相似文献