Meanwhile, with the coastline changes, the accreting tidal flats
constantly changed, so the management of newly formed land was
also an important content for coastal management. The newly
deposited tidal flats were surveyed regularly so that they could be
assigned to each of the saltworks. Thus, management for the new
tidal flats was an important embodiment for the government to
implement the AGSD system. The government usually surveyed the
new accretion tidal flats area every few years in the Ming and Qing
Dynasties. As recorded in Chronicle of the L. sea salt industry (Xie,
1694; Ga, 1728; Wang, 1748, 1892; Ji, 1806) of different period in
the Qing Dynasty, the new accreted areas had been measured in
5e10 year intervals. Based on the survey results, the new land was
classified into different types, e.g., sand flats and grass land, and the
potential for providing grass were evaluated. The purpose of the
tidal flat management and the regularly survey was to consolidate
the system of land use and continue to fight against private reclamation.
A large amount of accreting coastal tidal flats also provided
important conditions for the salt industry development (Bao, 2013).