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201.
ABSTRACT: Hydrologic records from six small Eastern Kentucky watersheds were analyzed to determine the effect of surface mining on storm flows and peak flows. Average storm flow volumes were not changed by surface mining, whereas average peak flows were increased 36 percent. Peak flow increases were only in the summer. Smaller peak flows are doubled; moderate ones are increased by about a third; peak flows around 100 csm seem to be largely unaffected; and the larger peak flows may have been reduced by surface mining. The maximum annual storm flows, usually in winter or spring, appeared slightly reduced. No time trend in either storm flows or peak flows could be detected in five years of postmining record. Surface mining is not a serious floodwater discharge problem. 相似文献
202.
ABSTRACT: A study was conducted in which 66 Parshall flumes used for agricultural flow measurement were assessed for physical integrity, settlement, and submergence. A total of 292 physical defects was documented. A flow measurement error analysis was performed indicating that 52 percent of the flumes measured flow beyond ±3 percent of the correct value and 41 percent of the flumes measured flow beyond ±5 percent. The findings indicate that the infrastructure is aging. The flow measurement system comprised of flumes no longer provide an accurate accounting of water through the distribution network. 相似文献
203.
Bryan ND Barlow J Warwick P Stephens S Higgo JJ Griffin D 《Journal of environmental monitoring : JEM》2005,7(3):196-202
Pulsed column experiments using Co, fulvic acid and porous sediment packing, along with up/down-flooding experiments using Eu, humic acid and intact sandstone blocks have been performed. The elution of metal and humic and their distribution along the sandstone columns have been measured. A mixed equilibrium and kinetic coupled chemical transport model has been used to simulate the results. In both cases, one exchangeable and one non-exchangeable component have been used to simulate the interaction of metal and humic substance. For the pulsed experiments, a simple equilibrium approach was used to model humic sorption, while a two component, kinetic model was required for the sandstone columns. 相似文献
204.
Development of a multilevel Ecological Classification System for the state of Minnesota 总被引:3,自引:0,他引:3
The Minnesota Department of Natural Resources (MNDNR) began development of an Ecological Classification System (ECS) in 1991. The ECS is hierarchically organized into six levels following the United States Forest Service structure. The upper four levels are being developed State-wide by an interdisciplinary group from several agencies. Geographic Information Systems approaches are being used to overlay and integrate existing data. The first two levels (Province and Section) have been completed. The third level (Subsection) is nearly completed, and work on the fourth level (Land Type Association (LTA)) started in January 1995. Classification and inventory for the lowest two levels (Ecological Land Type and Ecological Land Type Phase) was cooperatively undertaken on two Land Type Associations within the Chippewa National Forest. A sample set of management interpretations is being developed and tested for the two lower levels. Workshops demonstrating how ECS can be used for natural resource management began in mid-1995 and will continue for several years, as will development of the lower two levels on LTAs beyond the Chippewa National Forest. 相似文献
205.
Using the Organizational Culture Profile (OCP), this research investigated the extent to which fit between individuals (n = 136) and their competency groups (P–G fit) and the organization (P–O fit) were related to job satisfaction. Even in a consulting firm with a strong organization culture, we found small, but interpretable, differences between the value‐based cultures of the competency groups in the firm. Although the two forms of fit were highly correlated, both individual consultants' fit with the culture of their competency group and the organization as a whole were significant predictors of job satisfaction. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
206.
Bryan E. Porter 《Journal of Safety Research》1998,29(4):223-233
Recruiting intervention agents is a promising procedure to increase the reach of community-safety programs. Finding active and effective agents, however, has not always been a systematic process. One recent approach named Actively Caring (AC) hypothesizes that self-esteem, belongingness, empowerment, extroversion, and reactance constructs predict willingness to help others. This approach was tested as a mechanism for finding successful agents. Urban college students (N = 360) were asked to (a) complete a survey of AC measures and (b) volunteer to promote fire safety to others by distributing commitment cards requesting fire-safe behaviors. In all, participating volunteers (N = 107) motivated commitments from 278 households. These households represented many communities of the urban area, giving evidence that college students may be useful resources for promoting safe behaviors. However, the AC approach was not as effective as selected individual psychosocial and demographic variables in predicting active and effective agent behaviors. Implications for the AC approach, and other prosocial behavior models, for selecting intervention agents a priori are discussed. 相似文献
207.
Amending soils with compost may lead to accumulation of metals and their fractions at various concentrations in the soil profile. The objectives of this study were to determine 1) the accumulation of Cu, Fe, Mn, and Zn with depth and 2) the distribution of water soluble, exchangeable, carbonate, Fe-Mn oxides, organic and residual forms of each metal in soils amended with MSW compost, co-compost, biosolids compost and inorganic fertilizer (as control). Total concentrations of Cu, Fe, Mn and Zn were concentrated in the 0-22 cm soil layer and scant in the rock layer. These metals were in the decreasing order of Fe > Mn > Zn > or = Cu. Copper, Fe, and Zn were predominantly in the residual form followed by fractions associated with Fe-Mn oxides, carbonate, organic, exchangeable and water soluble in all treatments except MSW compost amended soil where the organic fraction was higher than the carbonate fraction. In fertilizer, co-compost and biosolids compost treated soils Mn concentrated mainly in the Fe-Mn oxides form followed by residual, carbonate, and organic forms whereas, in MSW compost treated soil the same pattern occurred except that Mn organic fraction was higher than that in the carbonate form. The MSW compost has a greater potential to be used as a soil amendment to supply plants with Cu, Mn and Zn than other treatments in calcareous soils of south Florida. 相似文献
208.
Karen M. Cogliati Bryan D. Neff Sigal Balshine 《Behavioral ecology and sociobiology》2013,67(3):399-408
In many mating systems, males adopt alternative reproductive tactics (ARTs) to maximize reproductive success. In fishes, guarding males often invest more energy into courtship, defense, and paternal care, whereas cuckolding males forego such costs and steal fertilizations by releasing their sperm in the nest of a guarding male. These two tactics have been documented in the plainfin midshipman fish (Porichthys notatus), yet the relative reproductive success of the guarding and cuckolding male tactics remains unknown. In this study, we used microsatellite markers to determine the level of paternity of the guarding type I males. We explored how paternity varied with male phenotype and across the breeding season. Our results revealed the lowest documented levels of paternity in a species with obligate paternal care. Although paternity remained consistently low, it did increase as the breeding season progressed. Male body size did not significantly predict paternity. The low paternity in this species may be explained, in part, by aspects of their reproductive ecology including the duration of parental care period, limited nest availability and competition for nests, as well as the occurrence of nest takeovers. Overall, our findings contribute to the understanding of the ultimate factors underlying ARTs in this species and highlight the importance of investigating reproductive success across the entire breeding season. 相似文献
209.
Pilar Santidrián Tomillo Jack S. Suss Bryan P. Wallace Kimberly D. Magrini Gabriela Blanco Frank V. Paladino James R. Spotila 《Marine Biology》2009,156(10):2021-2031
Reproductive output of leatherback turtles (Dermochelys coriacea) is affected by the stochastic nature of emergence success. Average emergence success of nests at Playa Grande, Costa Rica
was 0.38 ± 0.27. Incubation temperature affected development of leatherback turtle eggs and emergence of hatchlings from the
nest. We found that high temperatures reduced hatching success and emergence rate and increased embryonic mortality both early
and late during incubation at Playa Grande. There was a temporal effect on emergence success that resulted in more hatchlings
being produced at the beginning of the season, because of higher emergence success, than toward the end. Likewise, production
of hatchlings varied from year to year. The average annual reproductive output was 252 ± 141 hatchlings per female. The 2005–2006
nesting season had the highest emergence success and produced the greatest number of hatchlings per female compared to the
2004–2005 (+120%) and 2006–2007 (+41%) seasons. However, average clutch size (62 ± 10) and clutch frequency (9.45 ± 1.63),
were not different among years. Turtles that had nested a high number of years exhibited greater clutch frequency and arrived
earlier to nest than turtles that had nested in fewer numbers of years. Nesting when environmental conditions favor high developmental
success and emergence rate may constitute an advantageous reproductive strategy. 相似文献
210.
Results are presented from a century-long 1/10° global ocean simulation that included a suite of age-related passive tracers. In particular, an ensemble of five global Boundary Impulse Response functions (BIRs, which are statistically related to the more fundamental Transit Time Distributions, TTDs) was included to quantify the character of the TTD when mesoscale eddies are explicitly simulated rather than parameterized. We also seek to characterize the level of variability in water mass ventilation timescales arising from eddy motions. The statistics of the BIR timeseries are described, and it is shown that the greatest variability occurs at early times, followed by a remarkable conformity between ensemble members at longer timescales. The statistics of the first moment of the BIRs are presented, and the upper-ocean spatial distribution of the standard deviation of the first moment of the BIRs discussed. It is shown that variations in the BIR first moment with respect to the ensemble average are typically only a few percent, and that the variability slightly decreases with increasing ensemble size, implying that only a few ensemble members may be necessary for a reasonable estimate of the TTD. The completeness of the estimated TTD, i.e., the degree to which the century long BIRs capture the range of global ocean ventilation timescales is discussed, and the potential for extrapolation of the BIR to longer times is briefly explored. Several regional BIRs were also simulated in order to quantify the relative abundance of fluid parcels that originate in specific geographical locations. 相似文献