The toxicity of heavy metals to coastal organisms can be modulated by changes in pH due to progressive ocean acidification (OA). We investigated the combined impacts of copper and OA on different stages of the green macroalga Ulva linza, which is widely distributed in coastal waters, by growing the alga under the addition of Cu (control, 0.125 (medium, MCu), and 0.25 (high) μM, HCu) and elevated pCO₂ of 1,000 μatm, predicted in the context of global change. The relative growth rates decreased significantly in both juvenile and adult thalli at HCu under OA conditions. The net photosynthetic and respiration rates, as well as the relative electron transfer rates for the adult thalli, also decreased under the combined impacts of HCu and OA, although no significant changes in the contents of photosynthetic pigments were detected. Our results suggest that Cu and OA act synergistically to reduce the growth and photosynthetic performance of U. linza, potentially prolonging its life cycle.

重金属对沿海生物的毒性可以通过海洋逐渐酸化 (OA) 引起的 pH 值变化来调节。我们研究了铜和OA绿色大藻的不同阶段的综合影响石莼linza，其广泛分布在沿海水域，通过添加Cu（对照，0.125（介质，MCU）的下生长的藻类，和0.25（高) μM, HCu) 和升高的 pCO ₂在全球变化的背景下预测的 1,000 μatm。在 OA 条件下，HCu 的幼体和成体菌体的相对生长率均显着降低。尽管未检测到光合色素含量的显着变化，但在 HCu 和 OA 的共同影响下，成年菌体的净光合和呼吸速率以及相对电子转移速率也降低。我们的结果表明，Cu 和 OA 协同作用以降低U. linza的生长和光合性能，可能延长其生命周期。