Development of traditional agriculture in coastal areas

(1) Weifang's topography is high in the south and low in the north, which determines that most rivers flow from south to north.

(2) Wanyuan Garden is a famous ancient garden, which absorbs the essence of the north and south gardens and has a unique development on this basis. Today, it is also the Weifang Cultural Relics Exhibition Hall, which used to be the original site of Weifang Museum. Colorful cultural relics are displayed in turns in batches and opened to the audience, adding rich cultural connotations to this famous garden.

(3) The coastal beaches in the northern coastal area of Weifang are vast, which provides favorable conditions for mariculture and sea salt production.

(4) Weifang is high in the south and low in the north, with low mountains and hills in the south, accounting for one third of the total area of Weifang. Others are plains and tidal flats, with a vast area of cultivated land and a long history of development, and insufficient reserve resources for reclamation. With the increase of population, the per capita arable land is decreasing.

So the answer is: (1) flows from south to north; (2) Ten water gardens; (3)AB； (4) alternating current.