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1.
Research on interactions among wave, current, and vegetation has received increasing attention. An explicit depth-averaged hydrodynamic model coupled with a wave spectral model (CMS-wave) was proposed in this study in order to simulate the wave and wave-induced current in coastal waters. The hydrodynamic model was based on the finite volume method while the intercell flux was computed by employing the Harten–Lax–van Leer approximate Riemann solver to investigate the dry-to-wet interface, and the drag force of vegetation was modeled as the sink terms in the momentum equations. The CMS-wave model was used to investigate the non-breaking and the breaking random waves propagation in vegetation fields. Afterwards, an empirical wave energy dissipation term with plant effect was derived to represent the resistance induced by aquatic vegetation in the wave-action balance equation. The established model was calibrated and validated with both the experimental and field data. The results showed that the wave height decreased significantly along the wave propagation direction in the presence of vegetations. The sensitivity analysis for the plant density, the wave height, and the water depth were performed by comparing the numerical results for the wave height attenuation. In addition, wave and wave-induced current through a finite patch of vegetation in the surf zone were investigated as well. The strong radiation stress gradient could be produced due to the variation of the energy dissipation by vegetation effect in the nearshore zone, which impacted the direction and amplitude of the longshore current. The calculated results showed that the coupling model had good performance in predicting wave propagation and the current over vegetated water regions.  相似文献   

2.
Studies evaluating human–wildlife interactions (HWIs) in a conservation context often include psychometric scales to measure attitudes and tolerance toward wildlife. However, data quality is at risk when such scales are used without appropriate validation or reliability testing, potentially leading to erroneous interpretation or application of findings. We used 2 online databases (ProQuest Psych Info and Web of Science) to identify published HWI studies that included attitude and tolerance. We analyzed these studies to determine the methods used to measure attitudes or tolerance toward predators and other wildlife; determine the proportion of these methods applying psychometric scales; and evaluate the rigor with which the scales were used by examining whether the psychometric properties of validity and reliability were reported. From 2007 to 2017, 114 published studies were identified. Ninety-four (82%) used questionnaires and many of these (53 [56%]) utilized a psychometric scale. Most scales (39 [74%]) had at least 1 test of reliability reported, but reliance on a single test was notable, contrary to recommended practice. Fewer studies (35 [66%]) reported a test of validity, but this was primarily restricted to structural validity rather than more comprehensive testing. Encouragingly, HWI investigators increasingly utilized the necessary psychometric tools for designing and analyzing questionnaire data, but failure to assess the validity or reliability of psychometric scales used in over one-third of published HWI attitude research warrants attention. We advocate incorporation of more robust application of psychometric scales to advance understanding of stakeholder attitudes as they relate to HWI.  相似文献   

3.
This work investigates the capability of an oceanic numerical model dynamic and thermodynamically coupled to a three-dimensional mesoscale atmospheric numerical model to simulate the basic features of the air–sea interaction in the coastal upwelling area of Cabo Frio (RJ, Brazil). The upwelling/downwelling regime is an important feature in the oceanic circulation of Cabo Frio and determines the sustainability of local ecosystems. This regime is predominantly driven by the atmospheric circulation and is well documented, being suitable to be used as test reference for atmospheric and oceanic coupled and uncoupled models. The oceanic boundary conditions, coastline shape and coupling effect have been tested. The uncoupled oceanic model forced by a NE (SW) wind field generates a realistic upwelling (downwelling) phenomenon regardless of the proximity of the lateral boundary and how realistic is the shape of the coastline. The atmospheric-oceanic coupled model generates an upwelling location and intensity similar to the uncoupled simulation, but the upwelling is gradually enhanced by the sea-breeze circulation. It also generates vertical profiles of mixing ratio that compare better to the observations than the uncoupled simulation and air potential temperature and wind vertical profiles that represent particular features of the atmospheric circulation at Cabo Frio.  相似文献   

4.
The quality of cultivated consumed vegetables in relation to environmental pollution is a crucial issue for urban and peri-urban areas, which host the majority of people at the global scale. In order to evaluate the fate of metals in urban soil–plant–atmosphere systems and their consequences on human exposure, a field study was conducted at two different sites near a waste incinerator (site A) and a highway (site B). Metal concentrations were measured in the soil, settled atmospheric particulate matter (PM) and vegetables. A risk assessment was performed using both total and bioaccessible metal concentrations in vegetables. Total metal concentrations in PM were (mg kg?1): (site A) 417 Cr, 354 Cu, 931 Zn, 6.3 Cd and 168 Pb; (site B) 145 Cr, 444 Cu, 3289 Zn, 2.9 Cd and 396 Pb. Several total soil Cd and Pb concentrations exceeded China’s Environmental Quality Standards. At both sites, there was significant metal enrichment from the atmosphere to the leafy vegetables (correlation between Pb concentrations in PM and leaves: r = 0.52, p < 0.05) which depended on the plant species. Total Cr, Cd and Pb concentrations in vegetables were therefore above or just under the maximum limit levels for foodstuffs according to Chinese and European Commission regulations. High metal bioaccessibility in the vegetables (60–79 %, with maximum value for Cd) was also observed. The bioaccessible hazard index was only above 1 for site B, due to moderate Pb and Cd pollution from the highway. In contrast, site A was considered as relatively safe for urban agriculture.  相似文献   

5.
This paper investigates the impacts of different turbulence models on the biological state at an ocean station in the northern Adriatic sea, named S3, comparing them with other uncertainties inherent to coupled physical–biological simulations. The numerical tool is a 1-D model resulting from the coupling of two advanced numerical models. The hydrodynamic part is modelled using the General Ocean Turbulence Model (www.gotm.net), in a version adopting state-of-the-art second-moment Turbulence Closure Models (TCMs). Marine biogeochemistry is parameterized with the Biogeochemical Flux Model (http://www.bo.ingv.it/bfm), which is a direct descendant of ERSEM (European Regional Sea Ecosystem Model). Results, obtained by forcing the model with hourly wind and solar radiation data and assimilating salinity casts, are compared against monthly observations made at the station during 2000–2001. Provided that modern second-moment TCMs are employed, the comparisons indicate that both the physical and the biological dynamics are relatively insensitive to the choice of the particular scheme adopted, suggesting that TCMs have finally ‘converged’ in recent years. As a further example, the choice of the nutrient boundary conditions has an impact on the system evolution that is more significant than the choice of the specific TCM, therefore representing a possible limitation of the 1-D model applied to stations located in a Region of Freshwater Influence. The 1-D model simulates the onset and intensity of the spring–summer bloom quite well, although the duration of the bloom is not as prolonged as in the data. Since local dynamics appears unable to sustain the bloom conditions well into summer, phytoplankton at the station was most likely influenced by river input or advection processes, an aspect that was not found when the S3 behaviour was adequately modelled using climatological forcings. When the focus is in predicting high-frequency dynamics, it is more likely that lateral advection cannot be neglected. While the physical state can be satisfactorily estimated at these short time scales, the accurate estimation of the biological state in coastal regions still appears as rather elusive.  相似文献   

6.
There has been a growing interest on using local modelling techniques for the analysis of spatio-temporal data because of their powerfulness in extracting the underlying local patterns in the data. In this study, we propose a two-step local smoothing approach to explore spatial patterns and temporal trends of spatio-temporal data via combining the geographically weighted regression and the local polynomial smoothing procedure. The proposed method incorporates both spatial and temporal information into the calibration process and makes it easier to implement visualization of the results. A simulation experiment is conducted to assess the performance of the proposed method and the results show that the method works satisfactorily. A real-world spatio-temporal data set is analyzed to demonstrate the practical usefulness of the method.  相似文献   

7.
A dispersive liquid–liquid microextraction procedure for cadmium(II) as its 2-(5-bromo-2-pyridylazo)-5-diethylamino-phenol chelate is presented. Carbon tetrachloride and methanol were used as extraction and dispersive solvents, respectively. After phase separation, the preconcentrated-separated cadmium(II) is determined by flame atomic absorption spectrometry with a microinjection technique. The factors which affected the extraction efficiency, i.e. the pH of the sample solution and the volumes of reagent and sample were investigated. The effects of some alkali, alkali earth, and transition metal ions, and of some anions on the recovery of cadmium were also studied. A preconcentration factor of 250 was obtained for a sample volume of 50?mL under optimum conditions. The method was validated by analysis of certified reference materials and applied to some water samples from Turkey.  相似文献   

8.
《Ecological modelling》2004,175(2):197-216
A Finite Element Ecological Model for the Lagoon of Venice (VELFEEM) has been used to test the responses of the Lagoon of Venice ecosystem to variations in physical conditions.The model is obtained by coupling a finite element hydrodynamic model, that computes the velocity fields of water, an energetic model to compute the water temperature fields, and an ecological model that simulates the dynamic of phytoplankton, zooplankton, nutrients (ammonia, nitrate and phosphate) organic detritus (organic nitrogen, organic phosphorous and CBOD) and dissolved oxygen.The transport model is a two-dimensional barotropic finite element model which allows for a better resolution of the lagoon morphology.The ecological model has been developed by starting from the ecological module EUTRO of WASP (Water Analysis Simulation System released by US EPA), and by adapting it to the peculiarity of the Lagoon of Venice.A reference condition has been identified by running a 1-year simulation under climatologic condition. Then, the sensitivity to physical forcing (tide and wind) and to the input of macronutrients has been investigated, by comparing model predictions of spatial and temporal evolution of major state variables and of an aggregate index of Water Quality Trophic Index (TRIX).  相似文献   

9.
Environmental Geochemistry and Health - The accumulation of potentially toxic elements (PTEs) in terrestrial ecosystems has become a global concern, as PTEs may exert a wide range of negative...  相似文献   

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