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51.
HENRY LEE II DEBORAH A. REUSSER† JULIAN D. OLDEN‡ SCOTT S. SMITH† JIM GRAHAM§ VIRGINIA BURKETT JEFFREY S. DUKES†† ROBERT J. PIORKOWSKI‡‡ JOHN MCPHEDRAN§§ 《Conservation biology》2008,22(3):575-584
Abstract: Changes in temperature, precipitation, and other climatic drivers and sea-level rise will affect populations of existing native and non-native aquatic species and the vulnerability of aquatic environments to new invasions. Monitoring surveys provide the foundation for assessing the combined effects of climate change and invasions by providing baseline biotic and environmental conditions, although the utility of a survey depends on whether the results are quantitative or qualitative, and other design considerations. The results from a variety of monitoring programs in the United States are available in integrated biological information systems, although many include only non-native species, not native species. Besides including natives, we suggest these systems could be improved through the development of standardized methods that capture habitat and physiological requirements and link regional and national biological databases into distributed Web portals that allow drawing information from multiple sources. Combining the outputs from these biological information systems with environmental data would allow the development of ecological-niche models that predict the potential distribution or abundance of native and non-native species on the basis of current environmental conditions. Environmental projections from climate models can be used in these niche models to project changes in species distributions or abundances under altered climatic conditions and to identify potential high-risk invaders. There are, however, a number of challenges, such as uncertainties associated with projections from climate and niche models and difficulty in integrating data with different temporal and spatial granularity. Even with these uncertainties, integration of biological and environmental information systems, niche models, and climate projections would improve management of aquatic ecosystems under the dual threats of biotic invasions and climate change. 相似文献
52.
Amey S. Tilak Michael R. Burchell II Mohamed A. Youssef Richard R. Lowrance Randy G. Williams 《Journal of the American Water Resources Association》2014,50(3):665-682
The riparian ecosystem management model (REMM) was field tested using five years (2005‐2009) of measured hydrologic and water quality data on a riparian buffer located in the Tar‐Pamlico River Basin, North Carolina. The buffer site received NO3‐N loading from an agricultural field that was fertilized with inorganic fertilizer. Field results showed the buffer reduced groundwater NO3‐N concentration moving to the stream over a five‐year period. REMM was calibrated hydrologically using daily field‐measured water table depths (WTDs), and with monthly NO3‐N concentrations in groundwater wells. Results showed simulated WTDs and NO3‐N concentrations in good agreement with measured values. The mean absolute error and Willmott's index of agreement for WTDs varied from 13‐45 cm and 0.72‐0.92, respectively, while the root mean square error and Willmott's index of agreement for NO3‐N concentrations ranged from 1.04‐5.92 mg/l and 0.1‐0.86, respectively, over the five‐year period. REMM predicted plant nitrogen (N) uptake and denitrification were within ranges reported in other riparian buffer field studies. The calibrated and validated REMM was used to simulate 33 years of buffer performance at the site. Results showed that on average the buffer reduced NO3‐N concentrations from 12 mg/l at the field edge to 0.7 mg/l at the stream edge over the simulation period, while the total N and NO3‐N load reductions from the field edge to the stream were 77 and 82%, respectively. 相似文献
53.
Dr. R. Harold Holbrook Jr Ann M. Krovoza Susan Schelley James E. Ferguson II 《黑龙江环境通报》1987,7(9):653-655
Anencephaly in twin B was accompanied by elevated amniotic fluid alpha-fetoprotein (AFP) and a positive acetylcholinesterase (AChE) band on gel electrophoresis in both twin sacs, although twin A was normal. AChE results did not help distinguish the false positive AFP in this set of twins, implying that AChE may diffuse transamniotically as has been previously postulated for AFP. In light of the low concordance rate for neural tube defects in twins, patient counselling in this situation must include the information that AFP and AChE may be falsely elevated in normal twin when the other twin has a neural tube defect. 相似文献
54.
Kryshev AI 《Journal of environmental radioactivity》2003,64(1):67-84
The paper outlines the results of the ECOMOD model application to simulate 90Sr dynamics in fish dwelling in Southern Ural lakes and contaminated as a result of the Kyshtym accident. The detailed reconstruction of 90Sr behavior in fish for the 40-year period (1957-1997) was made for the most contaminated lakes (Uruskul and Berdenish). The adapted ECOMOD model was applied for the other 14 Ural lakes to explain the peculiarities in 90Sr accumulation by fish in lakes with different concentrations of Ca2+ ions in lake water. 相似文献
55.
The paper presents the extraction of data from the EPIC database, outlining the effects of chronic radiation exposure in fish. The EPIC database 'Radiation effects on aquatic biota' is compiled as part of the current EC Project EPIC (Environmental Protection from Ionizing Contaminants in the Arctic). The EPIC database is based on information from publications in Russian (Russian/former Soviet Union data). The data are focused on the effects in fish at relatively low doses of chronic radiation exposure. The effects are grouped by three key endpoints: morbidity, reproduction, and mortality/life shortening. A preliminary scale of dose-effects relationships for fish has been constructed. 相似文献
56.
Spatial relationships and matrilineal kinship in African savanna elephant (Loxodonta africana) clans
Russell A. Charif Rob Roy Ramey II William R. Langbauer Jr. Katharine B. Payne Rowan B. Martin Laura M. Brown 《Behavioral ecology and sociobiology》2005,57(4):327-338
African savanna elephants, Loxodonta africana, live in stable family groups consisting of adult females and their dependent offspring. During the dry season, clans consisting of several family groups typically share a common home range. We compared spatial relationships and mitochondrial DNA (mtDNA) haplotypes among 14 adult female elephants within 3 clans during the dry season in northern Zimbabwe. Spatial relationships were studied by radio-tracking. Home-range similarity was quantified by correlating the estimated utilization distributions of all pairs of elephants. Clans were identified by cluster analysis of the home-range similarity values. All three clans contained at least two of the five mtDNA haplotypes that were found, indicating that clan members are not necessarily matrilineally related. Within clans, home ranges of elephants with the same haplotype were not significantly more similar to each other than those of elephants with different haplotypes. Most elephants within each clan used their shared home ranges independently of each other: the distribution of distances between their positions at any given time did not differ from the distribution expected by chance. However, 8 out of the 26 within-clan pairs exhibited long-term coordination of space use by remaining within known hearing distance of each others low-frequency calls significantly more often than expected by chance. At least four of these coordinated pairs consisted of animals in different family groups. Elephants in three of the four different-family pairs whose movements were coordinated had different haplotypes. Further research is needed to determine the relationship between these coordinated movements and conventionally defined bond-group behavior.Electronic Supplementary Material Supplementary material is available in the online version of this article at .Communicated by C. Nunn 相似文献
57.
W. Walker II R.W. Risebrough W.M. Jarman B.W. de Lappe J.A. Tefft R.L. DeLong 《Chemosphere》1989,18(9-10):1799-1804
A compound detected in extracts of blubber of harbor seals,
, found dead in Puget Sound in the north-western United States over the period 1972–1982 was identified as
(chlorophenyl)methanol from its mass spectral characteristics and by synthesis. Concentrations in harbor seal blubber ranged from 23 to 750 ng/g of the lipid weight and showed no evident changes over the time interval of the study. Concentrations were highly correlated with those of most of the other organochlorines detected in the harbor seal extracts, indicating a similar pattern of uptake and accumulation. The compound is used in the manufacture of optically active polymers, which appear to be a plausible source. 相似文献
58.
Gerard A. Nyssen Eric T. Miller Todd F. Glass Charles R. Quinn II Julie Underwood David J. Wilson 《Environmental monitoring and assessment》1987,9(1):1-11
Solubilities of several hydrophobic organic substances (paradichlorobenzene, endrin, naphthalene, and dibutyl phthalate) in aqueous solutions containing up to 0.10 mole fraction of common alcohols and ketones, were measured by gas chromatography. The solubilities are significantly increased by the alcohols and ketones. The results are interpreted in terms of the association of n molecules of alcohol or ketone with each hydrophobic organic molecule. Values of n and the equilibrium constant for this association are reported for each hydrophobic organic-alcohol and organic-ketone combination. The implications of these results for the disposal of toxic wastes by landfilling is discussed. 相似文献
59.
B. L. Turner II 《Journal of Land Use Science》2016,11(6):689-697
ABSTRACTLand system science (LSS) has expanded its research focus from the drivers of land-use and -cover change primarily in rural wildlands to include the social-environmental consequences of this change, urban areas, and sustainability practice. Land system architecture, interacting with the landscape mosaic approach in ecology, offers a special niche for the entry of rural areas and wildlands into urban sustainability research through examinations of the composition and configuration of ‘cityscapes’. Given the fine-grain data requirements of heterogeneous cityscapes, emergent land architecture-mosaic approaches have largely explored the urban heat island (UHI) problem, a topic that links LSS with the interests of urban climatology, engineering, and planning in city morphology or geometry. The subtle distinctions in the treatment of land configuration between land architecture-mosaic approaches and urban morphology-geometry approaches are identified. Several examples of the land architecture-mosaic approach illustrate the understanding gained about the UHI problem as well as its complementarity with morphology-geometry approaches. This understanding provides insights about the design of urban areas at the parcel to neighborhood scales to ameliorate extreme temperatures, an issue of increasing concern for urban areas worldwide and consistent with the sustainability problems identified by such international programs as Future Earth. 相似文献
60.
N. Roth M. Southerland J. Chaillou R. Klauda P. Kazyak S. Stranko S. Weisberg L. Hall Jr. R. Morgan II 《Environmental monitoring and assessment》1998,51(1-2):89-106
As a step towards determining the extent of degradation in non-tidal streams, a multi-metric Index of Biotic Integrity (IBI) based on fish assemblages was developed for the Maryland Biological Stream Survey (MBSS). The MBSS is a probability-based statewide sampling program designed to assess the status of biological resources and to evaluate the effects of anthropogenic activities. We used data from 419 MBSS sites sampled in 1994-95 to develop the IBI. Two distinct geographic strata, corresponding with ecoregional and physiographic boundaries, were identified via cluster analysis and multivariate analysis of variance (MANOVA) as supporting distinctly different species groups. Reference conditions were based on minimally degraded sites. We quantitatively evaluated the ability of various attributes of the fish assemblage (candidate metrics) to discriminate between these reference sites and sites known to be degraded, using statistical tests and classification efficiency. Provisional formulations of the IBI were selected for each region based on high classification efficiency and broad representation of fish assemblage attributes. Fish IBI scores for 1995 MBSS sites spanned a wide range of biological conditions, from good to very poor. Over all six basins sampled in 1995, half of the stream miles fell into the range of good to fair. Roughly 25% of stream miles showed some degradation. The IBI will be used in conjunction with physical and chemical data to answer critical questions about the health of Maryland streams and the relative impacts of human-induced stresses on the state's aquatic systems. 相似文献