With the rapid development and application of new techniques, cartography has entered the 21 st centu- ry's digital period form computer-assist mapping in the 1970s, traditional map representation ahs transformed from 2-D, mono-medium, static into 3-D, multi-media, dynamic and network (including internet), and gradually is developing to- wards 4-D (time, space). There appeared digital map, electronic map, soft map, hard map, interactive map, mingle map etc. Agricultural map needs to include much more contents in 3-D, multi-media than other types of map.
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