Intensive Pyropia aquaculture in the coast of southwestern Yellow Sea and its subsequent waste, including disposed Ulva prolifera, was speculated to be one of the major sources for the large-scale green tide proceedin...Intensive Pyropia aquaculture in the coast of southwestern Yellow Sea and its subsequent waste, including disposed Ulva prolifera, was speculated to be one of the major sources for the large-scale green tide proceeding in the Yellow Sea since 2007. It was, however, unclear how the detached U. prolifera responded and resumed growing after they detached from its original habitat. In this study, we investigated the growth and photosynthetic response of the detached U. prolifera to various temperature, salinity and irradiance in the laboratory. The photosynthetic rate of the detached U. prolifera was significantly higher at moderate temperature levels（14–27℃）and high salinity（26–32）, with optimum at 23℃ and 32. Both low（14℃） and highest temperature（40℃）, as well as low salinity（8） had adverse effects on the photosynthesis. Compared with the other Ulva species, U. prolifera showed higher saturated irradiance and no significant photoinhibition at high irradiance, indicating the great tolerance of U. prolifera to the high irradiance. The dense branch and complex structure of floating mats could help protect the thalli and reduce photoinhibition in field. Furthermore, temperature exerted a stronger influence on the growth rate of the detached U. prolifera compared to salinity. Overall, the high growth rate of this detached U. prolifera（10.6%–16.7% d^–1） at a wide range of temperature（5–32℃） and salinity（14–32） implied its blooming tendency with fluctuated salinity and temperature during floating. The environmental parameters in the southwestern Yellow Sea at the beginning of green tide were coincident with the optimal conditions for the detached U. prolifera.展开更多
Since 2007,large-scale green tides dominated by Ulva prolifera consecutively bloomed in the Yellow Sea and caused great economic losses.The fouling U.prolifera on the Pyropia yezoensis aquaculture rafts in the Subei S...Since 2007,large-scale green tides dominated by Ulva prolifera consecutively bloomed in the Yellow Sea and caused great economic losses.The fouling U.prolifera on the Pyropia yezoensis aquaculture rafts in the Subei Shoal was regarded as the major source of the floating biomass.However,it was still unclear about the seed source of fouling green macroalgae attached on the rafts.In this study,the field surveys and the indoor experiments were conducted to reveal the source of propagules of the fouling green macroalgae on the rafts and to study the anti-fouling material for P.yezoensis aquaculture rafts which could possibly be a feasible strategy to control the green tides in the Yellow Sea.The results showed that（1） micro-propagules of several green macroalgal species,including U.prolifera,U.linza,U.compressa,U.flexuosa,and Blidingia sp.coexisted in the waters and sediments in the Subei Shoal and their proportion remarkably changed over time;（2） the bamboo poles with peeling treatment could significantly reduce the amount of U.prolifera micro-propagules attached.This study confirmed that the micro-propagules distributed in the Subei Shoal area were the precursors of the green tides,and provided a feasible method to control the Yellow Sea large-scale green tides at the beginning.展开更多
基金The Special Funds for Basic Ocean Science Research of FIO under contract Nos 2012T08,2014G33 and 2008T30the National Natural Science Foundation of China-Shandong Joint Funded Project“Marine Ecology and Environmental Sciences”under contract No.U1406403+1 种基金the National Natural Science Foundation of China under contract Nos 41206162 and 41206161the National Basic Research Program(973 Program)of China under contract No.2010CB428703
文摘Intensive Pyropia aquaculture in the coast of southwestern Yellow Sea and its subsequent waste, including disposed Ulva prolifera, was speculated to be one of the major sources for the large-scale green tide proceeding in the Yellow Sea since 2007. It was, however, unclear how the detached U. prolifera responded and resumed growing after they detached from its original habitat. In this study, we investigated the growth and photosynthetic response of the detached U. prolifera to various temperature, salinity and irradiance in the laboratory. The photosynthetic rate of the detached U. prolifera was significantly higher at moderate temperature levels（14–27℃）and high salinity（26–32）, with optimum at 23℃ and 32. Both low（14℃） and highest temperature（40℃）, as well as low salinity（8） had adverse effects on the photosynthesis. Compared with the other Ulva species, U. prolifera showed higher saturated irradiance and no significant photoinhibition at high irradiance, indicating the great tolerance of U. prolifera to the high irradiance. The dense branch and complex structure of floating mats could help protect the thalli and reduce photoinhibition in field. Furthermore, temperature exerted a stronger influence on the growth rate of the detached U. prolifera compared to salinity. Overall, the high growth rate of this detached U. prolifera（10.6%–16.7% d^–1） at a wide range of temperature（5–32℃） and salinity（14–32） implied its blooming tendency with fluctuated salinity and temperature during floating. The environmental parameters in the southwestern Yellow Sea at the beginning of green tide were coincident with the optimal conditions for the detached U. prolifera.
基金The National Natural Science Foundation of China under contract Nos 41606190 and 41506185the Fundamental Research Funds for FIO under contract No.2015G09+1 种基金the Foundation of Key Laboratory of Integrated Monitoring and Applied Technologies for Marine Harmful Algal Blooms,SOA under contract Nos MATHAB201507 and MATHAB201806Shandong Natural Science Foundation under contract No.ZR2016DB22
文摘Since 2007,large-scale green tides dominated by Ulva prolifera consecutively bloomed in the Yellow Sea and caused great economic losses.The fouling U.prolifera on the Pyropia yezoensis aquaculture rafts in the Subei Shoal was regarded as the major source of the floating biomass.However,it was still unclear about the seed source of fouling green macroalgae attached on the rafts.In this study,the field surveys and the indoor experiments were conducted to reveal the source of propagules of the fouling green macroalgae on the rafts and to study the anti-fouling material for P.yezoensis aquaculture rafts which could possibly be a feasible strategy to control the green tides in the Yellow Sea.The results showed that（1） micro-propagules of several green macroalgal species,including U.prolifera,U.linza,U.compressa,U.flexuosa,and Blidingia sp.coexisted in the waters and sediments in the Subei Shoal and their proportion remarkably changed over time;（2） the bamboo poles with peeling treatment could significantly reduce the amount of U.prolifera micro-propagules attached.This study confirmed that the micro-propagules distributed in the Subei Shoal area were the precursors of the green tides,and provided a feasible method to control the Yellow Sea large-scale green tides at the beginning.
