ABSTRACT
The aim of this chapter is to review our knowledge of the effects of climate change on the dynamics and persistence of plant populations. In common with many other chapters in this book, we concentrate primarily on the effects of elevated [CO
] as this is the background against which responses to other environmental changes will occur, that is, it is interactions between [CO
] and temperature or precipitation changes that are relevant and we include these where they are known. While there is a strong theoretical case that plant physiological responses to elevated [CO
] should be modified by temperature (Morison and Lawlor 1999), there is very little evidence for [CO
]–temperature interactions operating on higher-order responses
(Morison and Lawlor, 1999; Norby and Luo, 2004). For example, Volder et al. (2004), Newman et al. (2001), and Lilley et al. (2001) found no interactive effects of temperature and [CO
] on the dry matter yields of forage plants; similarly there were no interactive effects observed on the productivity of the tree species
Pinus sylvestris
(Peltola et al.,
Pseudotsuga menzeisii
(Olszyk et al., 2003), or
Acer rubrum
(Norby et al., 2003). Species diversity effects also appear unresponsive (Zavaleta et al., 2003; Harmens et al., 2004). Despite limited evidence for frequent [CO
]–temperature interactions, we cannot ignore the possibility that these may occur (Shaw et al., 2002), and the quantitative outcome of additive effects, of course, are also of interest.
