Ecosystem services are supplied directly by natural capital, i.e. the major components of the land system: soil, water, vegetation and other biotic components. Land use decisions therefore have direct bearing on natural capital and ecosystem services supply (Crossman et al., 2013). The impacts of these decisions typically unfold at local to regional scales, affecting local livelihoods that depend on ecosystem services and biodiversity (Wu, 2013b). Trade-offs often arise between bundles of ecosystem services supplied by alternative land uses (Chisholm, 2010; Crossman et al., 2011; Smith et al., 2013). For example, conversion from natural forest to annual cropping or grazing systems (Figure 5) may enhance food production, but at the cost of a number of other services, such as water purification, , carbon sequestration, and habitat quality for biodiversity. The conservation or promotion of cultural and spiritual values that are associated to particular land uses may also be favoured or disfavoured following major land use changes . To understand (and eventually manage) these trade-offs between alternative land use scenarios, we need , rrobust quantifications or estimates of the many services supplied by natural and transformed ecosystems. . Land system science plays a pivotal role in modelling and quantifying the bio-physical processes underpinning ecosystem services; some of which are better understood (e.g. sediment transport processes under alternative land use arrangements, biomass content of different land covers), while others are less so (e.g. the distribution and dynamics of some components of biodiversity and the supply of habitat-related ecosystem services (Nagendra et al., 2013a).
Land science can also help understanding the social dimension of natural capital and ecosystem services. Arguably, ecosystem services are co-produced by human-environment interactions, and do not exist if there are no beneficiaries. In consequence, there is a clear need to better understand the spatial and temporal dimensions of the beneficiaries and the nature of their connections; whether they co-occur or are far apart from where ecosystem services are supplied (Serna-Chavez et al., 2014). Moreover, land management for ecosystem services should be linked to the demand for services by potential beneficiaries. As societies and climate are changing, demand is changing both in terms of amount and spatial dynamics. Managing land in such ways that services are supplied to those areas where they are required is challenging and requires a major research effort, as the spatial flow and transport of services vary with the service type and beneficiary access; and these as channels of flows are rapidly changing.
A full consideration of the trade-off among alternative land management strategies and spatial allocation of resource use is needed to inform the public and policy debate on which developments of land use are most desirable. This includes aspects of composition, management and configuration of different land uses across multiple scales and organization levels, ranging from the farms to the whole planet. Such an approach goes beyond simple strategies of either multifunctional land use or spatial segregation of land functions (Grau et al., 2013) to a more nuanced, multi-scale assessment of alternative, context-sensitive, options; and should include (in addition to frameworks for specifically addressing future scenarios), strategies for adaptations to unpredicted ones.