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31.
Using hydrogeochemical signatures of stream water to assess pathways for rainfall events: towards a predictive model 下载免费PDF全文
J. A. Figueiredo E. A. Menor M. T. Taboada‐Castro M. M. Taboada‐Castro M. L. Rodríguez‐Blanco E. S. Braga 《水文研究》2014,28(4):2302-2311
Thanks to its simple division into agricultural and forestry land use, the Corbeira catchment (Galicia, Spain) is used as a case study to build a predictive model using hydrogeochemical signatures. Stream data acquired under recessional flow conditions over a one year period were obtained from a sampling station near the downstream end of the catchment, and using principal component analysis, it is shown that some of the analytical parameters are covariant, and some are negatively correlated. These findings support inferences about the pathways of rainfall in the catchment. Specific signatures may be associated with the dominant hydrological source, either surface runoff or subsurface waters: additionally, the dominant land use in that part of the catchment, where the flow originated, can also be predicted. The dominant runoff shows a strong covariance between suspended solids (SS) and particulate phosphorus (PP), with a clear negative correlation with pH. Dissolved organic carbon (DOC) data are associated with this covariant set when these compounds are available in the soils in question. Dissolved phosphorus, total organic nitrogen and dissolved nitrates are also associated with the same covariant set when the runoff flows through areas of extensive agricultural use. The SS ? PP covariance is less significant at lower flows. Typical base flow regimes show a significant covariance between salinity and pH, with a marked negative correlation with SS ? PP set, confirming the dominance of subsurface waters in the baseflow, as expected. Seasonally divergent DOC ? SS behaviour proves to be a useful tracer for rainfall regimes. The DOC trend shows a sinusoidal annual variation in amplitude, determined by the rainfall regime. As a result, flow from the catchment is dominated by surface water whenever there is synchronicity between the peaks of DOC and SS. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
32.
Astronomy Letters - Based on published data, we have produced a sample of 256 radio sources whose trigonometric parallaxes and proper motions were measured by VLBI. This sample contains Galactic... 相似文献
33.
Understanding what drives farmers’ voluntary adoption of nutrient and soil best management practices has important consequences for many environmental outcomes including water quality. We build on research revealing the need for simultaneous use of multiple nitrogen best management practices to achieve water quality improvement goals. Using social, economic and attitudinal variables we predict the use of multiple nitrogen best management practices at three time points: current use (2013), past use (before 2013), and likelihood of use on their largest field in the next three years. Our empirical analysis uses structural equation modeling with latent variables and 2014 farmer survey data from three Midwestern US states. Most farmers in our sample used at least one of the six best management practices. Our results reveal that farmers’ attitudes, use of information sources, and conservation program participation affect the number of nitrogen best management practices concurrently in use at multiple time points. 相似文献
34.
Mokievsky V. O. Udalov A. A. Chava A. I. Simakova U. V. Kokarev V. N. Neretina T. V. 《Doklady Earth Sciences》2020,493(2):645-648
Doklady Earth Sciences - The species composition and structure of bottom communities with a predominance of bivalve mollusks of the Portlandia genus, which are widespread on the shelf of the... 相似文献
35.
Tasev G. Serafimovski D. Volkov A. V. Boev B. Djordjevic T. Kolitsch U. Serafimovski T. 《Geology of Ore Deposits》2020,62(5):419-431
Geology of Ore Deposits - The Dudica deposit is located in the southern part of the Republic of North Macedonia (RNM), not far from the border with Greece in the Kozuf–Aridean volcanic... 相似文献
36.
Soboleva S. V. Evstigneeva T. E. Boeva N. M. Bortnikov N. S. 《Doklady Earth Sciences》2020,491(2):210-213
Doklady Earth Sciences - A structural model of the rare mineral yushkinite [(Mg0.60Al0.30V0.10)Σ1.0(OH)2] [V0.875S2] is studied using the data of electron microdiffraction and the X-ray powder... 相似文献
37.
Astronomy Reports - A comparison of the virial parameters of galaxies and galaxy clusters (radius, density, and entropy function) in a wide range of masses, $${{10}^{6}} \leqslant... 相似文献
38.
Gordeev V. V. Dara O. M. Alekseeva T. N. Kochenkova A. I. Boev A. G. Lokhov A. S. Belorukov S. K. 《Oceanology》2020,60(3):384-392
Oceanology - The paper presents the first results of a study of seasonal variations in the grain size distribution and mineral compositions of suspended particulate matter (SPM) of the Northern... 相似文献
39.
Zagidullin A. A. Usanin V. S. Petrova N. K. Nefedyev Yu. A. Andreev A. O. Gudkova T. V. 《Astronomy Reports》2020,64(12):1093-1106
Astronomy Reports - The work is devoted to the study of the physical libration of the Moon. Interest in the traditional topic related to the rotation of the Moon is stirred up by the activity of... 相似文献
40.
Doklady Earth Sciences - The content of polycyclic aromatic hydrocarbons (PAHs) in soil and snow cover near the carbon black plants in Moscow, Omsk, and Samara regions was studied. The differences... 相似文献