Distribution of main planting areas in China

(1) The dividing line between planting areas and non-planting areas in China is consistent with the annual precipitation line of 400 mm 。

(2) Compared with non-planting areas, the population density in planting areas in China is high.

(3) Topographically, plateaus and basins are the main landforms of non-main planting areas in China.

(4) Reading the table shows that the agricultural structure in Area C is mainly animal husbandry, which accords with the characteristics of Area C in the figure.

(5) Among the four regions in the picture, the Pearl River Delta region is suitable for developing export-oriented agriculture.

(6) As can be seen from the figure, the cultivated land contracted by Wang mainly grows rice, so it may be located in the middle and lower reaches of the Yangtze River, that is, D in the above figure, where there is sufficient heat and precipitation, which is a favorable climatic condition for developing agricultural production.

So the answer is:

( 1)B；

(2) large;

(3) Plateau; Basin;

(4)③;

(5)②;

(6)D； Sufficient heat and abundant precipitation.