Quantitative distribution and ecological characteristics of seagrass beds in the coastal area of Moye Island, Yellow Sea
LI Hong-chen;ZHANG Pei-dong;LI Wen-tao;YANG Xiao-long;HU Cheng-ye;LI Chang-jun;The Key Laboratory of Mariculture,Ministry of Education,Ocean University of China;
Seagrass bed is one of the three typical coastal ecosystems with a huge function of carbon reservation, providing important habitat and food sources to several marine organisms, and playing an important role in maintaining the balance of the inshore marine ecosystem. A field study was conducted in the coastal area of Moye Island, Yellow Sea, in August 2016. Seagrass beds covering approximately 272.84 ha were discovered that consisted of Zostera marina and Phyllospadix iwatensis as the dominant species. Z. marina was distributed in an area of 177.23 ha, which was approximately equivalent to 65% of the total distribution area. These Z. marina plants primarily grow in the farming ponds of Stichopus japonicus in the coastal area of Moye Island. P. iwatensis was distributed in an area of 95.61 ha, which was approximately equivalent to 35% of the total distribution area. These P. iwatensis plants primarily grow on rocky coasts with a marked banding distribution. The average shoot height, shoot density, and biomass of Z. marina were(86.8 ± 5.8) cm,(364.0 ± 14.2) shoots/m~2, and(528.7 ± 20.5) g DW/m~2, respectively. The average shoot height, shoot density, and biomass of P. iwatensis were(112.8 ± 3.8) cm,(3087.0 ± 35.4) shoots/m~2, and(2 320.0 ± 26.6) g DW/m~2, respectively. The average water depth of P. iwatensis beds was(1.80 ± 0.04) m, with a higher dissolved oxygen content of(10.4 ± 0.1) mg/L. The average grain size of farming ponds where Z. marina grew was(4.6 ± 0.1) mm. Historical data indicate that seagrass meadows in Moye Island have suffered extensive losses primarily due to excessive anthropogenic activities, except for natural disturbances. Conservation suggestions and actions are being put forward to provide an important basis for further study and for protecting the seagrass ecosystem in this region.