Agriculture & Biology
river flow
100%
Mississippi River
95%
sediments
62%
lakes
55%
crop acreage
55%
phosphorus
50%
total phosphorus
41%
wastewater treatment
37%
Minnesota River
32%
metropolitan areas
22%
acreage
21%
phosphorus fertilizers
20%
human population
18%
agricultural land
16%
land use
16%
cropping systems
16%
animal manures
16%
crop production
15%
basins
15%
statistical analysis
14%
fertilizers
12%
animals
7%
Earth & Environmental Sciences
phosphorus
49%
lake
39%
river flow
39%
trend
33%
river
33%
sediment
32%
fertilizer
16%
crop
13%
animal population
12%
waste water treatment plant
12%
crop production
10%
human population
9%
cropping practice
9%
metropolitan area
9%
manure
9%
wastewater treatment plant
8%
inflow
8%
agricultural land
7%
river basin
7%
land use
6%
loss
5%
basin
4%
method
2%