Agriculture Reference
In-Depth Information
tAble 18.1
estimates of the Pre-Agricultural and Present land Area in major
ecosystems
Prehistoric Area
Present Area
changes
ecosystem
10
9
ha
% of total
10
9
ha
% of total
10
6
ha
% of total
1. Forest
4.68
36.0
3.93
30.2
750
20.6
(a) Tropical
Rainforest
1.28
9.8
1.20
9.2
80
2.2
(b) Other
Forests
3.40
26.2
2.73
21.0
670
18.4
2. Woodland
0.97
7.5
0.79
6.1
180
4.9
3. Shrubland
1.62
12.5
1.48
11.4
140
3.8
4. Grassland
3.40
26.3
2.74
21.0
660
18.1
5. Tundra
0.74
5.7
0.74
5.7
0
0
6. Desert
1.59
12.2
1.50
11.5
90
2.5
7. Cultivated
0.0
0.0
1.55
11.9
1550
42.6
8. Pasture/
Plantations
0.0
0.0
0.27
2.2
270
7.5
Total
13.0
100
13.0
100
3640
100
Source:
Adapted from Williams, 1994; NRC, 1993.
tAble 18.2
Increase in world Population
year Population (millions)
10,000 BC
4
5,000 BC
5
1,000 BC
50
0 BC
170
500 AD
190
1000 AD
310
1500 AD
425
1700 AD
600
1800 AD
980
1900 AD
1650
1950 AD
2400
2000 AD
6070
2006 AD
6500
Source:
http://en.wikipedia.org/wiki/Image:Population_curve.svg
