In my last post on conservation land development, I discussed a cost concept—negative externalities. In this post, I cover a benefit concept—ecosystem services.
Third Key Term: Ecosystem Services
The third conservation land development term a legal professional should master—ecosystem services—is a dual ecology and economic concept.
Ecosystems are defined as a dynamic complex of plant, animal, and microorganism communities and the nonliving environment, all interacting as a functional unit. Ecosystems generate a variety of services that deliver economic value to both producers and consumers of residential land development projects. These beneficial values, in the form of ecosystem services, in increasing order of “tangibility” value to humans, are best categorized as follows:
(1) Passive use benefits such as mere existence value;
(2) Ecological services such as clean water, nutrient cycling, pollination, watershed protection, and carbon storage;
(3) Off-site benefits, such as scenic backdrops and other geographical-area “viewsheds” for residences (seasonal and full-time), universities, recreational facilities, and lodging, which in turn directly enhance property values and tax revenues;
(4) Community benefits, such as attracting and retaining non-recreation businesses and retirees and providing dependent recreation jobs; and
(5) Direct use benefits, such as on-site recreation, on-site hunting and fishing, and holistic use benefits.
The Rise of the Ecosystem Services Concept
Following a half-century history of growing ecological awareness and associated science-based environmental policy development efforts, the term “ecosystem services” arose to reflect the bridging of natural science and social science fields. The result is a functional linkage between science and policy practices.
In 1997 Gretchen Daily, the founder and faculty director of Stanford University’s Natural Capital Project, put forth a seminal definition for ecosystem services. Daily defined ecosystem services as those “conditions and processes through which natural ecosystems, and the species that make them up, sustain and fulfill human.” A few years later, a succinct definition has been put forth by the Millennium Ecosystem Assessment: ecosystem services are “the benefits people derive from ecosystems.” The Millennium Ecosystem Assessment is a United Nations initiative that commenced in 2001 to assess the consequences of ecosystem change for human well-being and the scientific basis for action needed to enhance the conservation and sustainable use of those systems.
In more scientific terms, what ecosystem services specifically do for humans is “maintain biodiversity and the production of ecosystem goods, such as seafood, forage timber, biomass fuels, natural fiber, and many pharmaceuticals, industrial products, and their precursors.” In addition to provisioning services or goods like food, wood, and other raw materials, ecosystems’ plants, animals, fungi, and microorganisms provide essential natural regulating services such as pollination of crops, prevention of soil erosion and water purification, and a vast array of cultural services, like recreation and a sense of place.
The Importance of the Ecosystem Services Concept for Legal Professionals
As residential land development continues to creep further into the exurban fringe, more and more natural land and the ecosystems they contain are altered. Such ecosystem alterations directly impact the natural land’s ecosystems and the provisioning of ecosystem services by such ecosystems. The importance of such impacts renders the memorization of the term’s definition insufficient for land use legal practitioners. Due to the increasing importance of ecosystem protection in the residential land use arena, legal practitioners will best serve clients by going beyond merely memorizing the term’s definition. Instead, legal practitioners need to see the bigger picture of how to apply the concepts that the term implicates in the residential real estate development process. That application—namely how enhanced protection of ecosystem services as part of a conservation development project can more than pay for itself— will be discussed in-depth in my next post.
 Negative externalities reflect unaccounted for costs that residential land development imposes on society due to the impacts caused by alterations to the ecosystems upon which residential land development is built.
 Morton, supra note 4, at 1-4, fig. 1 (setting forth a conceptual list of ecosystem benefits). The total economic benefits generated by the ecosystems framework set forth by Morton on figure 1 is based in large part on the research of Beverly L. Driver et al., Wilderness Benefits: A State-of-Knowledge Review, U.S.D.A. FOREST SERVICE, INT.-220, 294 (1987), and others, as noted by Morton on page 2). See also Trista M. Patterson, The Economic Value of Ecosystem Services from and for Wilderness, 13(1) Int’l. J. Wilderness 27 (2007).
 Leon C. Bratt & Rudolf de Groot, The Ecosystem Services Agenda: Bridging the Worlds of Natural Science and Economics, Conservation, and Development, and Public and Private Policy, 1(1) Ecosystem Services 4 (2012).
 Gretchen C. Daily, Nature’s Services, 3 (3rd ed. 1997).
 See Trista M. Patterson & Dana L. Coelho, Ecosystem Services: Foundations, Opportunities, and Challenges for the Forest Products Sector, 257.8 forest ecology & management 1637 (2009).