Zobrazeno 1 - 10
of 26
pro vyhledávání: '"Cecily C. Y. Chang"'
Publikováno v:
Water Resources Research. 38:19-1
Publikováno v:
Hydrological Processes. 18:2699-2712
The natural abundance of nitrogen and oxygen isotopes in nitrate can be a powerful tool for identifying the source of nitrate in streamwater in forested watersheds, because the two main sources of nitrate, atmospheric deposition and microbial nitrifi
Autor:
John M. Melack, Delores M. Lucero, Al Leydecker, Cecily C. Y. Chang, James O. Sickman, Carol Kendall, Joshua P. Schimel
Publikováno v:
Biogeochemistry. 64:1-24
Mechanisms underlying catchment export of nitrogen (N) during seasonal transitions (i.e., winter to spring and summer to autumn) were investigated in high-elevation catchments of the Sierra Nevada using stable isotopes of nitrate and water, intensive
Publikováno v:
Canadian Journal of Fisheries and Aquatic Sciences. 59:1874-1885
A study was conducted to determine whether NO3 stable isotopes (δ15N and δ18O), at natural abundance levels, could discriminate among NO3 sources from sites with different land uses at the basin scale. Water samples were collected from 24 sites
Publikováno v:
Hydrological Processes. 15:1285-1300
An Erratum has been published for this article in Hydrological Processes 16(5) 2002, 1129–1130. Nitrate (NO3) and other nutrients discharged by the Mississippi River are suspected of causing a zone of depleted dissolved oxygen (hypoxic zone) in the
Autor:
Cecily C. Y. Chang, Donald H. Wilkison, Ronald J. Avanzino, Steven R. Silva, Carol Kendall, A.C. Ziegler
Publikováno v:
Journal of Hydrology. 228:22-36
A new method for concentrating nitrate from fresh waters for δ15N and δ18O analysis has been developed and field-tested for four years. The benefits of the method are: (1) elimination of the need to transport large volumes of water to the laborator
Autor:
Cecily C. Y. Chang, Steven R. Silva, James Langston, Mike Riggs, Carol Kendall, Donald H. Campbell
Publikováno v:
Canadian Journal of Fisheries and Aquatic Sciences. 56:1856-1864
Recently, methods have been developed to analyze NO3- for δ15N and δ18O, improving our ability to identify NO3- sources and transformations. However, none of the existing methods are suited for waters with low NO3- concentrations (0.7-10 µM). We d
Autor:
Richard Petersen, Cecily C. Y. Chang
Publikováno v:
Canadian Journal of Fisheries and Aquatic Sciences. 52:54-62
Nous avons recueilli des echantillons d'eau du lac Tahoe a des stations situees au milieu du lac et pres du rivage, a trois profondeurs (25, 50 et 75 m, ce qui correspondait a un eclairement d'environ 10, 1 et 0,1% de l'intensite lumineuse a la surfa
Publikováno v:
Canadian Journal of Fisheries and Aquatic Sciences. 49:1206-1215
Field measurements and bioassay experiments were coupled to investigate the interdependent processes affecting phytoplankton biomass at Lake Tahoe using a trace metal protocol. Water samples were analyzed for suspended particulate matter, dissolved o
Publikováno v:
Journal of Environmental Engineering. 116:394-409
Chemical and biological interactions involving arsenic (As) and phosphorus (P) appear to affect significantly As transport and distribution in Whitewood Creek, South Dakota. Data (first‐order uptake rate constants, standing crop, and accumulation f