SCOPE AND BACKGROUND OVERVIEW OF SIERRA NEVADA ECOSYSTEMS AND ASSESSMENT STATUS MANAGEMENT STRATEGIES FOR ECOSYSTEM SUSTAINABILITY INSTITUTIONAL INTEGRATION OF ASSESSMENTS AND SOLUTIONS THE FUTURE CURRENT PAGE: 8 of 15 rev. Jun. 17, 1996 © 1996 Regents of the University of California

Overview of Sierra Nevada Ecosystems and Assessment Status Review of the Sierra Nevada reveals the unfolding process that has shaped the ecosystems. A view of the Sierra is flawed if it considers todays ecological or social environment to be stable: the old-growth forests developed in a different environment from the current one and are headed into a different future. Many of the forests originated under an anomalously wet climate. The developed water systems are based on predictions of flow derived from this unusually favorable period. Snapshots of the present may give misleading pictures of what is needed to support a full range of biotic and human systems in the near and distant future. If there is natural environmental change, does this give license for humans to act however they like in ecosystems? If ecosystems are always changing, why should it matter if we retain the diversity and function of any specific time and place? It matters because both the rate and the direction of change in natural systems are extremely important to ecosystem sustain-ability. Plants and animals, and the ecosystems they compose, evolve and adapt to the gradual pace of most environmental change; that is, they produce the successors who are able to survive and prosper. Humans may make conscious decisions to alter rate and direction of ecosystem change. The important consideration is to make decisions with knowledge of the potential consequences and to understand the context of change in the Sierra Nevada. Social Institutions The web of institutions laid across the Sierra by successive generations of Americans is central to an understanding of the mountain range and its future management. This web is the eventual target of the current study, in that the projects assessments and strategies must be absorbed, adapted, and implemented not by the organisms or rocks of the mountain range but rather by the institutions through which human society operates. Institutions are central elements in the ecology of the Sierra Nevada because they mediate the relationship between the labor and desires of people and the Sierran ecosystems those people use. In a biological analogy, institutionsthe governmental and nongovernmental organizations, agreements, and regulationsconstitute a key part of the life history strategy that the human species currently uses in the Sierra. Institutions are how people link themselves to other parts of the ecosystem. Institutions govern not only what people extract from the ecosystemwater, timber, recreation, amenitiesbut also how they reinvest in the natural capital through actions such as planting trees or restoring habitats. The extent to which institutions and policies close the loopthat is, mitigate the environmental impact of human activitiesis a critical part of a Sierra Nevada ecosystem assessment. As institutions regulate the exchanges between people and the ecosystem, they also link people who reside outside the mountain range with the ecosystem within it. Institutions that close the loop by extracting water or reinvesting (for instance, watershed rehabilitation to mitigate for habitat loss) are also closing a loop that passes beyond the Sierra to include urban and agricultural water users in the San Francisco Bay Area, southern California, and the Central Valley. Closing the loop, then, includes identifying and accounting for the values of all stakeholders in the Sierra Nevada, regardless of their locations, and understanding how benefits and costs flow among coupled ecosystems. Although institutions are part of the ecology of the Sierra, nothing ensures that those institutions perceive the entire ecosystem, much less manage it in a sustainable manner. Heretofore, institutions have largely focused on portions of ecosystems. For instance, for streams on the east side of the Sierra, the Lahontan Regional Water Quality Control Board has jurisdiction over the quality of water, the state Water Resources Control Board over the rights to the water, the state Department of Fish and Game over the trout in the water, and the U.S. Forest Service and the state Department of Forestry and Fire Protection over the trees that grow next to the water. Jurisdictions split along geographic as well as resource lines. The U.S. Forest Service and the National Park Service manage the land along the upper reaches of most Sierran rivers, while private landowners, the federal Bureau of Land Management, municipal utilities, and local irrigation districts manage much of the land along the lower reaches. There are no existing mechanisms to ensure that the sum of the management of the parts of the ecosystem adds up to wise management of the whole ecosystem. Like all other parts of the Sierran ecosystem, the institutional components change over time in response to larger forces. Population growth and development bring more people into the region, increasing not only the demand for services but also the diversity of values and issues influencing management of the range. The creation of markets for values and benefits that heretofore have been allocated by right or administrative arrangementwater is the preeminent exampleupsets many existing arrangements and creates the need for different types of institutions. Interagency and intergovernmental cooperation blurs lines of authority and blunts institutional prerogative but may allow movement in arenas currently stymied by gridlock. Grassroots activism creates new institutions, which compete with existing ones for legitimacy and authority. These driving forces interact in different ways in different regions of the Sierra and force the evolution of institutions. Future policies and institutions need to transcend their ecosystem component status to perceive the Sierra Nevada as a set of ecosystems with links to stakeholders within and outside the range and to manage both extraction and reinvestment to ensure the long-term persistence of the ecosystem and the people that depend upon it. Rock and Soil The Sierra Nevada is an enormous deposit of granitic rocks whose exposed slopes are readily visible. The environmental history of the range has been shaped over several hundred million years by varying intensities and forms of uplift, erosion, volcanism, and glaciation. Plate tectonics and climate variations acting at millennial, decadal, and annual timescales interact to influence the intensity of these events and their impacts on the landscape. These diverse geological activities have produced a broad suite of rock formations in the Sierra Nevada, dominated by granitics but including many types of igneous, sedimentary, and metamorphic rocks, with ages from Cambrian (about 500 million years ago) to Quaternary (the past 2 million years). Most evidence suggests that the modern range is about 10 million years old, although very recent and controversial evidence suggests it is much older. Rocks of the Sierra Nevada interact with climate, topography, surface processes, and biota to create Sierra Nevada soils. Because the Sierra Nevada is underlain by mostly granitic rocks, soils that develop from these foundations are thin and rocky. Although the nutrient capital (fertility) of the soil in general over the Sierra Nevada is rather low, the range contains some of the most productive sites for conifers in the world. Soil types form a mosaic across the Sierra, influencing vegetation, erosion, wildlife distribution, water quality, fertility, and a myriad of human uses. Such a complex geological and soil foundation has dramatic implications for human uses of Sierra Nevada ecosystems. Mesozoic deposits (more than 100 million years old), altered through pressure and heat and exposed through erosion or buried deep underground, form the gold and silver that attracted a rush of miners and began the period of Euro-American settlement. Abundant sediments from ancient seafloors, lake beds, and water-carried deposits create the ore and gravel resources that are the contemporary valuable rocks of the Sierra. Persistent seismic activities, especially along volcanic vents of the eastern escarpment near Mammoth Lakes and Markleeville, are a focus of concern for urban development in these areas, yet those same vents provide geothermal power for existing communities. The rich and fertile soils that have formed on the western edges of the Sierra Nevada continue to support a diverse agriculture that had its origins with the Native American communities that occupied the region. Volcanic and seismic activity is highly localized but ongoing in the Sierra Nevada. New volcanic craters have been built, vents have erupted, hot springs have formed, faults have slipped, and volcanic-induced mud slides have occurred as recently as the past hundred years in a few regions. Volcanic events will undoubtedly persist as agents of change affecting local ecological and human elements of Sierran ecosystems and demanding local attention.