Adaption of Ulva pertusa to multiple-contamination of heavy metals and nutrients: Biological mechanism of outbreak of Ulva sp. green tide

Abstract The multiple-contamination of heavy metals and nutrients worsens increasingly and Ulva sp . green tide occurs almost simultaneously. To reveal the biological mechanism for outbreak of the green tide, Ulva pertusa was exposed to seven-day-multiple-contamination. The relation between pH variation ( V pH ), Chl a content, ratio of ( Chl a content)/( Chl b content) ( R chla / chlb ), SOD activity of U. pertusa ( A SOD ) and contamination concentration is V pH = 1.72 ± 0.38 + 1.68 ± 0.72 × 10 − 4 × C ammonia 2 (p  C chla  = 0.88 ± 0.09  − 0.01 ± 0.00  ×  C Cd (p  R chla / chlb = 0.72 ± 0.04 − 0.35 ± 0.08 × 10 − 4 × C Cd 2 (p  A SOD = 25.64 ± 2.35 − 0.41 ± 0.09 × 10 − 2 × C Zn 2 + 0.54 ± 0.10 × C Zn (p  C ammonia , C Cd and C Zn is concentration of ammonia, Cd 2 + and Zn 2 + , respectively. Comparing the contamination concentrations of seawaters where Ulva sp. green tide occurred and the contamination concentrations set in the present work, U. pertusa can adapt to multiple-contaminations in these waters. Thus, the adaption to multiple-contamination may be one biological mechanism for the outbreak of Ulva sp . green tide.