Abstract:

Understanding the effect of global climate change (GCC) on earth ecosystems is a key issue worldwide. Compared to terrestrial ecosystems, marine ecosystems are more sensitive to GCC. Stresses that GCC brings to oceans include warming, ocean acidification, changes in currents, sea level rise, and enhancement of ultraviolet radiation, etc. Phytoplankton are the key primary producers in marine ecosystems and very important in the ocean carbon cycle. Distribution patterns, primary productivity, community succession and phenology of phytoplankton can all be affected by GCC. For phytoplankton species distribution, the distribution region of warm-water species is generally extended, which is opposite the trend of cold-water species. Phytoplankton primary productivity is decreased globally, and phytoplankton cell sizes are gradually reduced. Intensity and timing of phytoplankton blooms are stronger and earlier, with a higher frequency of harmful algal blooms. Ocean acidification has been found to greatly affect the metabolisms and biodiversity of marine organisms, especially calcifying species. Enhancement of ultraviolet radiation may inhibit the growth of phytoplankton. Furthermore, El Niño, La Niña and enhanced precipitation will decrease phytoplankton biomass. The changes in phytoplankton growth and distribution will lead to variation of its biodiversity from the gene to ecosystem levels. Phytoplankton eco-physiological studies under GCC driven factors and long-term monitoring are key pathways for understanding the phytoplankton-diversity-ecosystem responses and feedbacks under GCC.

Key words: global climate change, phytoplankton, biodiversity, biomass, distribution, phenology, community structure