Composition and spatial structure of dwarf shrub heath in Norway     

Linda Aune-Lundberg  Geir-Harald Strand 《Norsk geografisk tidsskrift. Norwegian journal of geography》2017,71(1):1-11

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Exploring spatially varying and scale-dependent relationships between soil contamination and landscape patterns using geographically weighted regression     

《Applied geography (Sevenoaks, England)》2017

Landscape pattern is an important determinant of soil contamination at multiple scales, and a proper understanding of their relationship is essential for alleviating soil contamination and making decisions for land planners. Both soil contamination and landscape patterns are heterogeneous across spaces and scale-dependent, but most studies were carried out on a single scale and used the conventional multivariate analyses (e.g. correlation analysis, ordinary least squared regression-OLS) that ignored the issue of spatial autocorrelation. To move forward, this paper examined spatially varying relationships between agricultural soil trace metal contamination and landscape patterns at three block scales (i.e. 5 km × 5  km, 10 km × 10 km, 15 km × 15 km) in the Pearl River Delta (PRD), south China, using geographically weighted regression (GWR). This paper found that GWR performed better than OLS in terms of increasing R square of the model, lowering Akaike Information Criterion values and reducing spatial autocorrelation. GWR results revealed great spatial variations in the relationships across scales, with an increasing explanatory power of the model from small to large block scales. Despite a few negative correlations, more positive correlations were found between soil contamination and different aspects of landscape patterns of water, urban land and the whole landscape (i.e. the proportion, mean patch area, the degree of landscape fragmentation, landscape-level structural complexity, aggregation/connectivity, road density and river density). Similarly, more negative correlations were found between soil contamination and landscape patterns of forest and the distance to the river and industry land (p < 0.05). Furthermore, most significant correlations between soil contamination and landscape variables occurred in the western PRD across scales, which could be explained by the prevailing wind, the distribution of pollutant sources and the pathway of trace metal inputs.  相似文献   

Where do planes fly past overhead? Determining departure and arrival routes from radar traces     

《Applied geography (Sevenoaks, England)》2017

This paper questions the main techniques of mapping in the context of aircraft noise in the vicinity of airports, and compares these techniques in terms of their purpose, benefits and limitations. Then the paper describes a method to summarise radar traces of a given air transport departure or arrival route into a median route and its envelope containing 80% of flights. This makes it possible to map global and easy-to-read maps of current air procedures around airports based on actual pathways flown by the aircraft. It also makes it possible to investigate the impact of change in aeronautical procedures on the actual geography of air routes around airports. Such maps complement noise contour maps and offer a good basis for debating aeronautical procedures at airports whose operations expose the population to noise.  相似文献   

Estimation of new production in the North Sea: consequences for temporal and spatial variability of phytoplankton   总被引：2，自引：0，他引：2  

Richardson  Katherine; Pedersen  Flemming Bo 《ICES Journal of Marine Science》1998,55(4):574-580

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Tidal dynamics of the south-west lagoon of New Caledonia: observations and 2D numerical modelling     

《Oceanologica Acta》1998,21(1):69-79

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Measurements of the vertical correlation in turbulence under broken waves     

Claus Pedersen  Rolf Deigaard  James Sutherland 《Coastal Engineering》1998,35(4):231-249

Turbulence measurements have been carried out in the surf zone of a wave flume. The purpose of the measurements is to determine the length scale of the turbulence generated by the wave breaking. The length scale of the turbulence is estimated on basis of the correlation between simultaneous measurements of the vertical turbulent fluctuations, taken at different levels above the bed.  相似文献   

Degradation of Aromatic and Chlorinated Aliphatic Hydrocarbons in the Anaerobic Part of the Grindsted Landfill Leachate Plume: In Situ Microcosm and Laboratory Batch Experiments   总被引：2，自引：0，他引：2  

Poul L. Bjerg  Kirsten Riigge  Jesper Cortsen  Per H. Nielsen  Thomas H. Christensen 《Ground water》1999,37(1):113-121

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57Fe Mössbauer spectroscopy of tektites     

S. Rossano  E. Balan  G. Morin  J.-P. Bauer  G. Calas  C. Brouder 《Physics and Chemistry of Minerals》1999,26(6):530-538

Tektite glasses are investigated using ⁵⁷Fe Mössbauer spectroscopy. Room temperature spectra analysis is performed using two complementary analytical methods based on two-dimensional distributions of both isomer shift and quadrupole splitting. No a priori correlation between the two hyperfine parameters is considered. The first method, based on a shape independent distribution, provides the justification for the Gaussian distribution shape used in the second method. No ferric iron contribution is evidenced by Mössbauer spectra analysis in these samples, although several criteria are used. Ferrous iron sites are shown to be continuously distributed between four- and five-fold co-ordinated sites.  相似文献   

Modelling shallow water wave generation and transformation in an intertidal estuary     

《Coastal Engineering》1999,36(3):197-217

An experiment is described in which wave growth was measured in Manukau Harbour, a New Zealand estuary with relatively large fetches and extensive intertidal flats. Wave spectra were obtained from pressure sensors and current meters placed at six sites across the estuary. The SWAN third-generation spectral model was then used to simulate wave transformation during a part of the study period during which consistent south-westerly winds blew along the instrument transect. The simulations incorporated refraction by currents using output from a circulation model of the estuary. Measured wave variance spectra were compared with the model results, and the contributions of the various processes represented by source terms within the model were compared. It was found that, along with whitecapping, bed friction and exponential growth from wind input, four-wave nonlinear interactions played a dominant role. Some limitations were noted in the discrete interaction approximation which the SWAN model uses to compute the four-wave nonlinear interaction term.  相似文献   

Spatio-temporal suspended sediment fingerprinting under different land management practices     

Maziar Mohammadi  Abdulvahed Khaledi Darvishan  Nader Bahramifar  Seyed Jalil Alavi 《国际泥沙研究》2023,38(4):481-493

Understanding spatio-temporal suspended sediment dynamics is more important in large watersheds due to the decisive role of local source apportionment in sediment transport and yield. The Talar River with a large mountainous watershed in northern Iran, which plays a vital role in water supply for agriculture and drinking, recently has faced quality degradation. The current study explores the relative contribution of suspended sediment sources using geochemical tracers and fingerprinting techniqu...  相似文献