搜索结果: 1-15 共查到“海洋科学 Isotopic”相关记录31条 . 查询时间(0.052 秒)
A 180-Million-Year Record of Sea Level and Ice Volume Variations from Continental Margin and Deep-Sea Isotopic Records
180-Million-Year Record Sea Level and Ice Volume Variations Continental Margin Deep-Sea Isotopic Records
2015/7/9
The geologic record provides constraints on the rates, amplitudes, and mechanisms controlling globally averaged (eustatic) and relative (eustatic plus subsidence/uplift) changes of sea level on variou...
Isotopic invisibility of protozoan trophic steps in marine food webs
A plain Marine food web
2014/10/16
According to modern oceanographic perspectives that emphasize microbial pathways, phagotrophic protists
comprise one to several levels of intermediate consumers between phytoplankton and larger metaz...
Influence of bottom water anoxia on nitrogen isotopic ratios and amino acid contributions of recent sediments from small eutrophic Lonar Lake, central India
nitrogen isotopic ratios Influence
2014/4/2
Lonar Lake is a eutrophic, saline soda lake with permanently anoxic deep water. The high pH and
deoxygenation result in very elevated d15N of suspended particulate matter (SPM) and sediments due to
...
Oxygen isotopic composition of nitrate and nitrite produced by nitrifying cocultures and natural marine assemblages
Oxygen isotopic composition of nitrate nitrite produced nitrifying cocultures natural marine assemblages
2014/4/4
The δ18O value of nitrate produced during nitrification (δ18ONO3,nit) was measured in experiments designed to mimic oceanic conditions, involving cocultures of ammonia-oxidizing bacteria or ammonia-ox...
Oxygen isotopic composition of nitrate and nitrite produced by nitrifying cocultures and natural marine assemblages
Oxygen isotopic composition nitrate nitrite produced nitrifying cocultures natural marine assemblages
2014/4/3
Thed18 O value of nitrate produced during nitrification (d18ONO3,nit) was measured in experiments designed to mimic oceanic conditions, involving cocultures of ammonia-oxidizing bacteria or ammonia-ox...
Oxygen isotopic fractionation and exchange during bacterial nitrite oxidation
Oxygen isotopic fractionation exchange bacterial nitrite oxidation
2014/4/17
We elucidate the controls on thed18 O values of microbially produced nitrate by tracking thed18O of nitrite and nitrate during bacterial nitrite oxidation, which is the final step of the nitrification...
The isotopic and hydrologic response of small, closed-basin lakes to climate forcing from predictive models: Application to paleoclimate studies in the upper Columbia River basin
isotopic hydrologic closed-basin
2014/4/17
Simulations conducted using a coupled lake-catchment, hydrologic and isotope mass-balance model indicate
that small, closed-basin lakes in north-central Washington are isotopically sensitive to chang...
Oxygen isotopic exchange and fractionation during bacterial ammonia oxidation
fractionation during bacterial ammonia oxidation Oxygen isotopic
2014/4/16
We examined the oxygen isotopic systematics for ammonia oxidation, the first step in the regeneration of
nitrate from ammonium. In particular, oxygen isotopic fractionation and exchange with water we...
Isotopic niches and trophic levels of myctophid fishes and their predators in the Southern Ocean
Isotopic niches trophic levels myctophid fishes their predators in the Southern Ocean
2014/4/16
We report the trophic structure of a myctophid assemblage by measuring theisotopic niches of 14 species living in Kerguelen waters, southern Indian Ocean. Most of the species show distinct isotopic ni...
Natural isotopic composition of carbon (d13C) correlates with colony size in the planktonic cyanobacterium Gloeotrichia echinulata
Natural isotopic composition of carbon d13C correlates with colony size planktonic cyanobacterium Gloeotrichia echinulata
2014/4/18
To assess variability in carbon isotope signatures (δ13C) between and within populations under natural conditions, with a particular emphasis on colony size, we repeatedly collected planktonic colonie...
Nitrogen isotopic fractionation associated with growth on dinitrogen gas and nitrate by cyanobacteria
Nitrogen isotopic fractionation associated cyanobacteria
2014/4/18
This study investigated the bulk nitrogen isotopic composition and fractionation of marine and freshwater
cyanobacteria growing at the expense of atmospheric dinitrogen gas (N2) or nitrate (NO{
3
)...
Natural isotopic composition of carbon (d13 C) correlates with colony size in the planktonic cyanobacterium Gloeotrichia echinulata
Natural isotopic colony size
2014/4/18
To assess variability in carbon isotope signatures (d13
C) between and within populations under natural
conditions, with a particular emphasis on colony size, we repeatedly collected planktonic colo...
Supersaturated N2O in a perennially ice-covered Antarctic lake: Molecular and stable isotopic evidence for a biogeochemical relict
Supersaturated N2O perennially ice-covered Antarctic lake Molecular and stable isotopic evidence biogeochemical relict
2014/4/21
The east lobe of Lake Bonney, a permanently ice-covered lake in the McMurdo Dry Valleys, Antarctica, has a mid-depth maximum N2O concentration of 43.3 μmol N L-1 (>700,000% saturation with respect to ...
Isotopic heterogeneity and cycling of organic nitrogen in the oligotrophic ocean
Isotopic heterogeneity cycling of organic nitrogen oligotrophic ocean
2014/4/22
We measured the nitrogen (N) isotopic composition (δ15N) of a large set (n = 38) of high-molecular-weight (HMW) dissolved organic nitrogen (DON) samples isolated from the tropical and subtropical Nort...
Nitrogen and oxygen isotopic signatures of subsurface nitrate seaward of the Florida Keys reef tract
Nitrogen oxygen isotopic signatures subsurface nitrate seaward Florida Keys reef tract
2014/4/22
Hydrographic and nutrient structure and the nitrogen and oxygen isotopic compositions (d15N and d18O) of the nitrate pool seaward of the Florida Keys reef tract were measured in Summer 2003. Nitrate a...