خيارات البحث
النتائج 201 - 210 من 229
Research on a mechanism by which enhanced UV-radiation of the active sun affects weather and climate
2001
Schuurmans, C.J.E. | Tourpali, K. | Dorland, R. van
Distribution of ammonium-N in the water-soil interface of a surface-flow constructed wetland for swine wastewater treatment النص الكامل
2001
Szogi, A.A. | Hunt, P.G.
Most livestock wastewaters treated in constructed wetlands are typically rich in ammonium N. The objective of this study was to evaluate the soil-water ammonium distribution and the diffusive flux through the soil-water interface. Wetland system 1 (WS1) was planted to rush and bulrushes, and wetland system 2 (WS2) was planted to bur-reed and cattails. Nitrogen was applied at a rate of 2.5 g m-2 d-1. Interstitial soil water was sampled at 9, 24, 50, and 70 m from the inlet. In both wetlands, we found that NH4+ diffusion gradient and N losses were highest in the wetland system with lowest water depth. From other studies, we knew that shallower depths may have promoted a more effective interfacing of nitrifying and denitrifying environments. In turn, this N reduction in the water column may be the reason for steady NH4+-N upward diffusion fluxes. The assumed mechanism for N removal has been nitrification and denitrification but ammonia volatilization could also have occurred. Although diffusion may explain a significant portion of the material transport between the soil-water interface, the large differences in concentrations between outlet and inlet need further explanation.
اظهر المزيد [+] اقل [-]Description of the default climate scenario for impact projects in NRP-II
2001
Verweij, W. | Viner, D.
Building bridges, raising dikes
2001
Harmelen, A.K. van
Interbasin exchange, thermocline structure and the global overturning circulation of the (Atlantic) ocean: remote sensing and modelling
2001
Ruijter, W.P.M. de
Ocean-climate variability and sea level in the North Atlantic region since AD 0
2001
Plassche, O. van de
Land use, climate and biogeochemical cycles: feedbacks and options for emission reduction
2001
Hutjes, R.W.A.
Electricity in flux: sociotechnical change in the Dutch electricity system, 1970-2000
2001
Hofman, P.S. | Marquart, N.E
Dynamics of sociotechnical change in transport and mobility
2001
Moors, E.H.M. | Geels, F.W.
Micrometeorology of air/sea fluxes of carbon dioxide and dimethylsulphide
2001
Stoll, M.H.C.
