Earth & Environmental Sciences
bioenergy production
100%
bioremediation
71%
photosynthesis
71%
alga
61%
biomass
45%
nutrient
38%
organic fertiliser
36%
water pollution
28%
fossil fuel
26%
power plant
25%
sludge
22%
chemical
21%
biomass energy
19%
fuel oil
17%
arid environment
17%
environmental degradation
16%
crop production
15%
polysaccharide
15%
organic soil
15%
biofuel
15%
energy production
15%
flue gas
14%
pollution control
14%
twenty first century
13%
alternative energy
13%
carbon sequestration
13%
energy consumption
13%
greenhouse gas
12%
global warming
12%
wastewater treatment
12%
drug
12%
ammonia
11%
atmospheric pollution
11%
phosphate
11%
nitrate
10%
consumption
10%
animal
10%
wastewater
9%
liquid
8%
nitrogen
8%
pollutant
8%
oil
8%
world
8%
land
8%
need
7%