Comparative Ecological Modeling for Long-term Solution of Excess Nitrogen Loading to Surface Waters and Related Chronic and Systemic Human-Environment Problems

Abstract

Concurrent environmental problems including 1) excess CO2 emissions and climate change, 2) excess nitrogen export and eutrophication of surface waters, and 3) dependence on non-renewable fossil fuel energy supplies can be considered interdependent symptoms of a single systemic "humans in the environment disorder". This dissertation presents results from three integrated research projects to frame and solve this general human-environmental problem. As an interdisciplinary whole, the projects help define and characterize organizing principles for future human-environment systems without major carbon (C), nitrogen (N), energy and related problems. Forests and other non-human ecosystems provide model systems, as these communities self-sustain for 10,000 years and longer. Comparative studies of soils, C and N emissions, and food web networks provide transferable principles to guide local action for sustainability. Soils in long-term forest land-use stored more C and organic matter than soils in long-term agricultural use. These results recommend permaculture, agroforestry and perennial agriculture to provide food and other human needs while building soil and enhancing soil fertility. Audits of the Appalachian Laboratory in Frostburg, MD, showed this environmental science facility causes emissions of 70 times more C and 60 times more N than local forests can absorb. The Lab also is 99% dependent on non-renewable energy sources. This study provides data necessary to alter operations toward environmental sustainability. Comparisons of the U.S. beef supply network showed unusually high network ascendency (a whole-system efficiency measure), higher dependency on a few compartments and lower network connectance than four non-human food webs. Results support efforts to increase U.S. food supply reliability via local agriculture and diversified food network pathways. Overall, the research identifies a systemic cultural cause of the human-environment crisis in subordination of environmental value, quality and capacity to values in economic, social, scientific and other arenas. Elevation of environmental value to equal standing with other human values thus promises a solution to the global ecological crisis. Realization of such a cultural paradigm shift likely requires revisions to fundamental scientific definitions, theories and understanding of life, evolution and ecology, all of which now operate with a predominantly organismal model of life that likewise de-emphasizes the environment.