Page - 19 - in Biodiversity and Health in the Face of Climate Change

19 events like flooding, health trends are also influenced by social, political and wider environmental factors. Climate and biodiversity act as important ‘boundary conditions’ for human health and well-being. These boundary conditions exert an influence on many of the other elements that affect the health and well-being of individuals through natural environments and associated ecosystem functions (Barton and Grant 2006; Dahlgren and Whitehead 2007). The health status of any one person can be seen as a compos- ite of: individual characteristics (e.g. hereditary genetics), the living environment and life experiences, both physical and social (Fig.  2.1 (left)). Health is determined not only through external ecosystem-related  processes and factors, but also internal ones, for example, recognising that the human body itself hosts complex and biodi- verse ecosystems that have differing impacts on physical health (Garrett 2015; Ruokolainen et  al. 2017) (Fig.  2.1 (right)). External factors include the abundance, type and quality of the natural environment underpinned by ‘external’ biodiversity. Other external factors include  social connections (e.g. family and community), access to health infrastructure and income (e.g. through diet). Inevitably, all are  related to some extent to wider socio-economic and political contexts. The overarching aim of this chapter is to summarise the current evidence of the links between nature, biodiversity, health and climate change, with a particular emphasis on physical health  and well-being, defined as “the quality and perfor- mance of bodily functioning. This includes having the energy to live well, the capac- ity to sense the external environment and our experiences of pain and comfort” Fig. 2.1 Determinants of human health and well-being (Barton and Grant 2006, based on Dahlgren and Whitehead 1991), including biodiversity at the human scale (after Garrett 2015, Ruokolainen et  al. 2017) 2 Biodiversity, Physical Health and  Climate Change: A  Synthesis of  Recent Evidence