Download 090608研究院アワー

研究院アワーのお知らせ (EES seminar)
2014 年 12 月 8 日（月） (Dec 8, 2014) 17:00-18:00
Place： 環境科学院 D201
Chair: 仲岡 雅裕 (Masahiro Nakaoka)（厚岸臨海）
Kelp Forests in the Era of Climate Change
Jarrett E. K. Byrnes (University of Massachusetts Boston)
Kelps have the potential to dominate roughly one quarter of the world’s coastlines. These
temperate-water large brown algae provide a wide variety of key ecosystem services. They
provide habitat and food for many fish and invertebrate species. They are harvested themselves
for food and chemicals. Their structure can alter coastal hydrodynamics. Changes in kelp
populations can have large effects cascading through an ecosystem. We know that kelps have
the potential to be susceptible to climate change driven shifts in the ocean environment. Here I
discuss recent models and meta-analyses examining our current knowledge about the future of
kelp forest ecosystems. I show that models of kelp forest interaction webs incorporating climate
drivers suggest kelp declines in many systems around the globe. I present evidence from a
meta-analysis of extant time-series demonstrating that some regions are already experiencing
kelp declines, but that this pattern is not uniform. Using meta-analysis of kelp removal
experiments, I show that kelp losses have potentially very different effects on fish at different
trophic levels. I close with possibilities for future research, both from the scientific community
and citizen scientists, to help us better understand how kelp forests across the globe might shift
in the era of climate change.
Marine Biodiversity and Ecosystem
Function in a Warming Ocean
Mary I. O’Connor (University of British Columbia)
Marine biodiversity is dynamic; species’ abundance and distribution are shifting with climate,
human-facilitated transport, disturbance, and natural causes. Despite concern globally for
biodiversity loss, recent analyses have suggested that locally species richness is relatively stable
despite changes in species composition. The future in marine ecosystems will reflect both
changes in species biodiversity, as well as how the constraints on biodiversity and its functional
consequences change with changing climate. Here, I consider the implications of current trends
in marine biodiversity for marine ecosystems given projections of ocean warming using climate
velocity metrics. Trends in biodiversity will occur within the context of marine ecosystem
function, which reflects the fundamental constraints of temperature on the biomass and energy
flow of food webs. Experimental work in aquatic food webs suggests that functional responses to
climate change will reflect constraints independent of shifts in biodiversity. A major challenge is
to identify ecosystem change that constrains biodiversity change, and the feedbacks then
between biodiversity and ecosystem function.