Medicine & Life Sciences
Groundwater
100%
Nitrates
74%
Isotopes
73%
Water
45%
Oxygen Isotopes
36%
Nitrogen Isotopes
23%
Oxygen-18
11%
Nitrogen-15
11%
Nitrogen Compounds
10%
Body Water
7%
Hydrogen
7%
Population Density
7%
Oxidation-Reduction
5%
Agriculture & Biology
groundwater
73%
stable isotopes
71%
nitrates
56%
water
27%
oxygen isotopes
27%
isotopes
25%
hydrograph
11%
isotope fractionation
8%
nitrogen compounds
7%
nitrogen
7%
instrumentation
7%
body water
6%
analytical methods
6%
hydrogen
5%
population density
5%
sampling
2%
Earth & Environmental Sciences
stable isotope
57%
nitrate
49%
groundwater
40%
water
20%
isotope
18%
nitrogen isotope
14%
contamination
12%
oxygen isotope
11%
oxygen isotope ratio
8%
hydrogen isotope
7%
pollutant
7%
nitrogen compound
7%
hydrograph
6%
population density
5%
instrumentation
5%
analytical method
5%
water body
5%
isotopic composition
5%
fractionation
5%
analysis
4%
Chemical Compounds
Stable Isotope
74%
Groundwater
73%
Nitrate
51%
Isotope
21%
Instrumentation
6%
Fractionation
5%
Chemical Transformation
3%
Environment
3%
Social Sciences
water
53%
environmental pollution
30%
population density
11%
environmental impact
9%