Plant Physiological Responses to Climate and Environmental Change

A future climate and environmental regime will affect plant physiology and induce higher order responses. Implications of rising atmospheric carbon dioxide are positive for plant growth, but less so than predicted from the theory of photosynthesis, because of feedback effects within the plant, and from ecosystem level feedback effects. Rising temperatures will reduce freezing and chill stress incidence, but warming will increase metabolic rates. High extremes will induce heat-shock responses. Higher plants are physiologically well-defended against projected increases in UV-B. Interactions between stresses will be multifaceted, but theory is poorly developed to make projections of their net result. A focus on testing theory using field-based experiments will be an important way forward. Keywords: acclimation; global change; heat shock; photosynthesis; respiration; stress