Characteristics of Water Quality Changes in the Futian Mangrove National Natural Reserve

NIU Zhiyuan1, SHEN Xiaoxue1, CHAI Minwei1, XU Hualin2, LI Ruili1,†, QIU Guoyu1,†

1. Shenzhen Engineering Laboratory for Water Desalination with Renewable Energy, School of Environment and Energy, Peking University, Shenzhen 518055; 2. Guangdong Neilingding-futian National Nature Reserve, Shenzhen 518041; † Corresponding authors, E-mail: liruili@pkusz.edu.cn (LI Ruili); qiugy@pkusz.edu.cn (QIU Guoyu)

Abstract The research monitored the water quality regularly and analyzed its spatial and temporal changes from 2014 to 2015 in the Futian Mangrove National Nature Reserve. Based on the water quality monitoring results from 2009 to 2014, the annual variation trend of water quality was also studied. The results showed that the DO was generally lower, and the average concentrations of TN, TP, COD and BOD, were 4, 2.6, 1.3 and 1.3 times higher than the class V standards of surface water respectively, the water was in heavy eutrophication status. The pollution level in dry season was significantly higher than in rainy season. From 2009 to 2014, the average concentrations of TN and TP showed a trend of decreasing firstly and then increasing, the BOD values kept rising and the COD values kept falling. Instead of heavy metals pollution, it was the organic pollution, mainly coming from the exogenous input, which have been the key problem of the water pollution, and it needs to take measures to control the pollution immediately. Key words Futian mangrove; water quality status; organic pollution; nutrient; heavy metal pollution; seasonal variation; annual variation

红树林(mangrove)是生长在热带亚热带海岸潮间带, 受到海水周期性浸淹的木本植物群落[1]。作为陆地和海洋之间的缓冲带, 红树林生态系统不仅

具有防浪护堤、促淤造陆、净化水质和维持生物多样性等重要生态功能[2], 还具有提供木材、水产养殖、食用、药用等经济价值[3], 同时也具有巨大的