Agriculture Reference
In-Depth Information
Table 12.3
. GWIs over two decades of the MCSE.
a
System
Global Warming Impact (GWI, g CO
2
e m
−2
yr
−1
)
Soil C
N Fertilizer
Lime
P
K
Seed
Pest
Fuel
N
2
O
CH
4
Net GWI Revised
Annual Crops (corn-soybean-wheat rotation)
Conventional
0 (31)
33
3
0.4
1.3
7.3
7.1
13
37 (6)
-1 (0)
101 (32)
No-till
-122 (31)
33
4
0.3
1.3
7.0
15.5
9
39 (3)
-1 (0)
-14 (31)
Reduced Input
-92 (122)
11
2
0.2
1.0
7.9
4.3
21
35 (2)
-1 (0)
-11 (122)
Biologically Based
-183 (31)
0
0
0
0
7.9
0
20
32 (3)
-1 (0)
-124 (31)
Perennial Crops
Alfalfa
-122 (92)
0
14
0.3
4
6
3
11
46 (4)
-1 (0)
-39 (92)
Poplar
61 (53)
3
0
0
0
0
2
1
6 (1)
-1 (0)
73 (53)
Successional Communities
Early Successional
-397 (31)
0
0
0
0
0
0
0
11 (1)
-1 (0)
-387 (31)
Mid-successional
-214 (275)
0
0
0
0
0
0
0
16 (3)
-3 (1)
-201 (275)
Mown Grassland (never
tilled)
0
0
0
0
0
0
0
0
11 (2)
-4 (0)
7 (2)
Deciduous Forest
0
0
0
0
0
0
0
0
12 (2)
-5 (1)
7 (2)
a
See Table 12.2 for further explanation. Mean values (±SE) are based on data from 1989 to 2009, except mean values of N
2
O and CH
4
are based on data from 1991 to 2011.
Source:
Revised from data in Gelfand et al. (2013).
