The terrigenous water source for Siang-Shan Wetland still in middle level pollution based on 4 season’s sampling analysis from 2018-2019, it was lower than previous inspection in 2017. In Ke-Ya creek, ammonium nitrogen contamination was too high in general, both in Ke-Ya creek estuary and Jin-Cheng lake, each with one case of lead contamination in water higher than regulation standard. In most cases, heavy metal contamination in wetland sediment and organism gathered by local people were lower than records in 2006, only lead (Pb) distribution with greater difference, Pb contamination in the sediment of Ke-Ya creek mouth near to sea increased significantly. According to sediment quality standard announced in 2010, many species of heavy metal contamination in Siang-Shan wetland recorded in 2006 and 2019 were higher than lower standard and lower than upper standard. According to Soil and Groundwater Pollution Remediation Act, sediment contamination monitoring in Siang-Shan wetland must conduct continually, and also must conduct monitoring on organism related to human food chain synchronously. After large scale mangrove forest removal in 2017, surface sediment structure changed as tidal current shifting, large area of sandy flat displaced previous muddy flat between lower tidal zone and embankment of Ke-Ya water recycling center, district for sustainable use near to Mei-Shan village with more muddy surface than before mangrove removal. After mangrove forest removed in 2017, quite a few of Xeruca formosensis (Rathbun, 1921) recolonized on high tidal zone, estimated population size was 230,000 all around wetland, the population size doubled in this year compared to 2017. The benthic invertebrate biodiversity around crab observing alley and parking site for oyster truck used by fishermen were similar to the district for sustainable using. Along the crab observing alley, 5-6 species of crabs could be spotted on wetland very easily, visitors step in muddy wetland from alley must be prohibited strictly.