Many environmental goods and
services are either public goods or partial public goods, and that is a key reason for their
under-provision. The non-rival70 and non-excludable71 characteristics of public goods mean that
markets alone will not be able to provide the socially optimum level – consumers can free-ride
and providers are not able to capture or charge for all the benefits provided by the good. For
example, use of farmland as a natural flood break provides flood defences for an entire region.
An individual benefiting from these defences does not reduce its availability for others (nonrival)
and individuals cannot be excluded from enjoying its benefits (non-excludable). As a
result, individuals may not be willing to pay for the benefit and providers may not be willing to
continue to supply it.