第1057回生物科学セミナー
Environmental stress in plants and global change
Enrico Brugnoli（Department of Earth System Science and Environmental Technologies National Research Council of Italy – Roma (Italy)）
2015年10月05日(月) 16：50-18：20 理学部2号館 講堂
In nature plants are exposed to multiple environmental stresses such as drought, salinity, unfavorable temperatures and high light. To cope with such stresses plants possess a series of mechanisms allowing them to survive in very harsh and unfavorable environments, for example, deserts, high mountains and Polar Regions. However, the response and adaptation of plants and ecosystems to the environment is further complicated by global change and predicting the impacts of such changes on terrestrial ecosystems is a relevant scientific challenge. Global climate change is inducing an increase in global average temperature by 0.8°C in the last century, but larger increases are being observed in some regions of Earth, such as the Arctic, the Mediterranean region and some deserts.
Increasing temperatures are also expected to intensify the hydrological cycle resulting in an increase in precipitation extremes, and change in the seasonal distribution of rain events, therefore increasing the probability of seasonal droughts and flooding events. Such stress may counterbalance the positive effect of increased CO2 concentrations on vegetation and its productivity and realistic estimates of the responses of ecosystems and feedbacks to changes in the principal regulators such as temperature, CO2, and water availability is not an easy task.
This presentation will provide an overview of a series of experiments to assess the response of plants and ecosystems to environmental stress and to a changing climate. Several approaches were used including measurements of leaf photosynthesis, ecosystem primary production by eddy covariance, stable isotopes, water-use efficiency and estimation of carbon sinks at plants and ecosystem levels (above ground, roots, soil carbon).
