Logo of State of the Environment 2011; Photo by Andrew Griffiths, Lensaloft

State of the Environment 2011 (SoE 2011)

State of the Environment 2011 Committee. Australia state of the environment 2011.
Independent report to the Australian Government Minister for Sustainability, Environment, Water, Population and Communities.
Canberra: DSEWPaC, 2011.

8 Biodiversity

1.2 Assessing and interpreting changes in biodiversity

We can interpret the state of biodiversity by:

The term ‘ecosystem services’ has been coined to describe benefits from the environment to humans, and to acknowledge that these benefits usually require interacting suites of species (i.e. ecosystems) rather than individual species. These benefits include services fundamental to human life, such as regulation of the atmosphere, maintenance of soil fertility, food production, regulation of water flows, filtration of water, pest control and waste disposal; and those that are social and cultural, such as experiencing nature. Figure 8.2 illustrates one framework for considering how ecosystem services link with human population growth and economic and other activities that consume natural resources.

Figure 8.2

Source: Adapted from Millennium Ecosystem Assessment7

Figure 8.2 The classification of benefits to humans (‘ecosystem services’) adopted by the Millennium Ecosystem Assessment

The arrows illustrate the strength of the linkages between categories of ecosystem services and components of human wellbeing and the extent to which it is possible for socioeconomic factors to mediate the linkage. For example, if it is possible to purchase a substitute for a degraded ecosystem service, then there is a high potential for mediation. The strength of the linkages and the potential for mediation differ in different ecosystems and regions. In addition to the influence of ecosystem services on human wellbeing depicted here, other factors—environmental, economic, social, technological and cultural—influence human wellbeing, and ecosystems are in turn are affected by changes in human wellbeing.

Interpreting the relationship between the current state of biodiversity and the ecosystem services the environment provides is complicated, for two reasons:

Evidence suggests that, while at any point in time human needs might be met by only some of the species currently in existence, some species that currently play a minor role might become more important as the environment changes.8-9 Many species can thus be seen as backups or ‘insurance’ against future changes in the environment or human needs. Related evidence suggests that the amount and types of benefits to humans change as components of biodiversity change (Table 8.2).10 This uncertainty and lack of knowledge about the relationship between biodiversity and human wellbeing suggests an imperative to retain options and to make decisions that do not foreclose on future opportunities. This translates into the widely adopted policy goal of protecting existing species, ecosystems and ecosystem processes, and the conditions for them to persist and evolve. This policy goal is recognised internationally in the Convention on Biological Diversitya and nationally in Australia’s Biodiversity Conservation Strategy 2010–2030.11

Table 8.2 Ecosystem services and their ecosystem service providers
Service Ecosystem service providers or trophic level Functional unitsa Spatial scalea
Aesthetic, cultural All biodiversity Populations, species, communities, ecosystems Local–global
Ecosystem goods Diverse species Populations, species, communities, ecosystems Local–global
Ultraviolet protection Biogeochemical cycles, microorganisms, plants Biogeochemical cycles, functional groups Global
Purification of air Microorganisms, plants Biogeochemical cycles, populations, species, functional groups Regional–global
Flood mitigation Vegetation Communities, habitats Local–regional
Drought mitigation Vegetation Communities, habitats Local–regional
Climate stability Vegetation Communities, habitats Local–global
Pollination Insects, birds, mammals Populations, species, functional groups Local
Seed dispersal Insects, birds, mammals, reptilesb Populations, species, functional groups Local
Pest control Invertebrate parasitoids and predators, and vertebrate predators Populations, species, functional groups Local
Purification of water Vegetation, soil microorganisms, aquatic microorganisms, aquatic invertebrates Populations, species, functional groups, communities, habitats Local–regional
Detoxification and decomposition of wastes Leaf litter and soil invertebrates; soil microorganisms; aquatic microorganisms Populations, species, functional groups, communities, habitats Local–regional
Soil generation and soil fertility Leaf litter and soil invertebrates; soil microorganisms; nitrogen-fixing plants; plant and animal production of waste products Populations, species, functional groups Local

a ‘Functional units’ refer to the unit of study for assessing functional contributions of ecosystem service providers; spatial scale indicates the scale(s) of operation of the service. The author’s assessment of the potential to apply this conceptual framework to the service was purposefully conservative and is based on the degree to which the contributions of individual species or communities can currently be quantified.

b Reptiles were not included in the original paper, but have been shown to be effective seed dispersers12-13

Source: Kremen14

awww.cbd.int/convention 

Parry Lagoons Nature Reserve, the Kimberley, Western Australia. Photo by Steve Parish