Nitrogen is indispensable to all life on Earth. However, humans now dominate the nitrogen cycle, and nitrogen emissions from human activity have real costs: water and air pollution, climate change, and detrimental effects on human health, biodiversity, and natural habitats. Too little nitrogen limits ecosystem processes, while too much nitrogen transforms ecosystems profoundly. The California Nitrogen Assessment is the first comprehensive account of nitrogen flows, practices, and policies for California, encompassing all nitrogen flows—not just those associated with agriculture—and their impacts on ecosystem services and human wellbeing. How California handles nitrogen issues will be of interest nationally and internationally, and the goal of the assessment is to link science with action and to produce information that affects both future policy and solutions for addressing nitrogen pollution. This book also provides a model for application of integrated ecosystem assessment methods at regional and state (subnational) levels.

What? Los Angeles was the original wine country of California, leading the state's wine production for more than a century? Los Angeles County was the agricultural center of North America until the 1950s? And where today's freeways soar, cows calmly chewed their cud? How could that be? Los Angeles, the capital of asphalt and Klieg lights, was once a paradise filled with grapevines and bovines, so abundant with Nature's gifts that no one could imagine a more pastoral place? Los Angeles County was the center of an agricultural empire. Today, it is the nation's most populous urban metropolis. What happened? Where did the green go? As Americans connect with gardens, farmers markets, and urban farms, most are unaware that each of these activities have deep roots in Los Angeles, and that the healthy food they savor literally had its roots in L.A. This book is for all who treasure the country's agrarian history.