Philip H. Brown earned a PhD in economics from the University of Michigan and took an interest in environmental applications such as ecosystem services and their economic valuation. There are four categories of ecosystem services: provisioning services which provide food, water and other resources; supporting services which enable processes like nutrient recycling; regulating services like air purification and waste decomposition; and cultural services like recreation. The economic value of ecosystem services is determined by calculating the costs a community would incur to replace the services naturally provided.

1. Understanding Ecosystem Services
and Their Economic Value
Philip H Brown, Economist

2. Introduction
 Philip H. Brown prepared for his career as an economist
by earning a PhD in economics from the University of
Michigan. In addition to core economics topics, Philip H.
Brown also took an interest in environmental
applications, such as ecosystem services and their
related economic valuation.
In determining the worth of the environment to humans,
particularly in terms of its economic value, one can look
at four different categories of benefits from a particular
ecosystem: provisioning services, supporting services,
regulating services, and cultural services.
Provisioning services include food, water, medicinal
products, and lumber. The processes that make these
services possible, known as supporting services, range
from nutrient recycling to soil formation.

3. Ecosystem Services
 Benefits such as air purification and waste decomposition
fall under the category of regulating services. Finally,
cultural services encompass any non-material benefit,
such as recreation or aesthetic enjoyment.
These four categories of ecosystem services are valued
in terms of the amount of money a community would
otherwise spend to replace those services. For instance,
wetlands naturally providing waste treatment services
help to prevent health problems. The economic valuation
is the cost of substituting a man-made system to provide
those same services. If the wetlands need restoration,
replacement could cost more than remediation of the
already existing ecosystem.