Earth & Environmental Sciences
anthropogenic factor
11%
comparative study
92%
drainage
7%
endangered species
11%
environmental factor
8%
exotic species
24%
herb
10%
invasive species
21%
lake
5%
native species
10%
natural heritage
13%
nutrient
6%
plant species
54%
program
5%
pteridophyte
30%
river
50%
sampling
5%
soil type
9%
tributary
9%
vegetation
61%
water chemistry
10%
watershed
74%
wetland
79%
woody plant
12%
Agriculture & Biology
comparative study
85%
drainage
10%
endangered species
10%
environmental factors
6%
ferns and fern allies
21%
graminoids
13%
herbaceous plants
11%
hydrochemistry
13%
indigenous species
8%
interspecific variation
9%
invasive species
20%
lakes
8%
nutrients
6%
rivers
80%
sampling
10%
soil types
10%
threatened species
11%
vegetation
75%
vulnerable species
13%
wetlands
100%
woody plants
10%