Opportunities for systematically valuing ecosystem service benefits produced by federal conservation programs
During the early years of the 20th century, as biologists strove to discover the processes governing plant succession, it was argued that a fundamental understanding would emerge not only by considering the suite of dynamic interactions among organisms but by expanding the conceptualization to include the inﬂuence of non-living factors contributed by climatic and soil complexes. This broader, integrative framework was described as an ecosystem (Tansley 1935). Nearly a century later, the ecosystem concept is recognized as an essential framework for assessing the long-run sustainability of natural capital within the United States (Anon. 2008) and around the world (Millennium Ecosystem Assessment 2005).