Agriculture & Biology
surface water
80%
water quality
72%
Mexico
59%
rivers
57%
pollution
23%
river water
22%
total nitrogen
18%
sulfates
15%
nitrates
15%
environmental policy
13%
industrial wastewater
13%
waterways
12%
biochemical oxygen demand
11%
sewage
10%
turbidity
9%
factor analysis
9%
anthropogenic activities
9%
effluents
8%
households
8%
Engineering & Materials Science
Surface waters
100%
Water quality
88%
Rivers
71%
Pollution
22%
Nitrates
20%
Sulfates
18%
Nitrogen
14%
Biochemical oxygen demand
12%
Turbidity
11%
Sewage
10%
Factor analysis
9%
Effluents
9%
Wastewater
8%
Restoration
7%
Earth & Environmental Sciences
surface water
49%
water quality
48%
river
35%
pollutant source
21%
river water
19%
agricultural effluent
17%
nitrate
15%
sulfate
14%
commercial activity
14%
river management
13%
water quality improvement
13%
nitrogen
12%
industrial activity
11%
waterway
10%
environmental policy
10%
factor analysis
10%
turbidity
9%
sewage
8%
comparison
8%
household
8%
human activity
8%
restoration
7%
parameter
7%
plan
7%
wastewater
6%
pollution
6%
index
5%
analysis
2%
Chemistry
Surface Water
76%
Sulfate
54%
Nitrate
54%
Nitrogen
43%
Turbidity
40%
pH Value
30%
Wastewater
29%
Reduction
16%
Time
13%