Boulder Creek CZO II: Evolution, Form, Function, and Future of the Critical Zone

University Of Colorado At Boulder, Boulder CO

Investigators

Abstract

The central aims of the Boulder Creek Critical Zone Observatory (BcCZO) are to understand how the surface of the earth, or critical zone, is shaped by climate, organisms, and geology, and how it will respond to changing conditions in the future. The focus is on the 'architecture' of the critical zone, meaning the topographic lay of the land, and distribution of soils, rock outcroppings, and vegetation communities. This architecture reflects evolution in response to geologic processes and climate. The work addresses fundamental questions, such as: How does rock turn to sediment? How do landscapes evolve? What controls water, sediment, dissolved mineral and nutrient fluxes? What services do ecosystems provide? The Colorado Front Range is used as a natural laboratory for these questions; it typifies mountainous areas of the American West that support large human populations, and it bears legacies from a varied geologic and climatic history. Addressing how changing snow, wildfires and landuse will affect the critical zone depend on this fundamental knowledge of critical zone architecture, function, and evolution. The objectives are: 1) Document critical zone (CZ) evolution by determining rates of erosion of the range and its adjacent basin, and documenting the structure of the CZ at key sites. 2) Study weathering, transport, and biological processes that shape the CZ. 3) Analyze how CZ architecture governs the storage and flow of water, nutrients and sediments. 4) Model CZ functional response to near-future changes in temperature and precipitation, and associated changes in ecosystem and fire regime. 5) Communicate findings through talks, papers, K-12 education, undergraduate classes, and shared models. Methods include: 1) monitoring weather and water in selected sites, 2) sampling rock, soil, vegetation, and water for physical, chemical, and genetic data, 3) collecting rock, geophysical data and outcrop descriptions of CZ structure, 4) constructing conceptual and numerical models to quantify CZ evolution in past, present-day, and future scenarios. The transformative nature of the program lies in its integrative and interdisciplinary approach. BcCZO brings together ecologists, hydrologists, and geologists to study snowmelt, subsurface water flow, biota, soils and weathering. Monitoring of recent weather and fire events that have perturbed water, sediment, and solute export stimulate modeling efforts that can be used to project into a changing climate. Future-casting hydrologic and ecosystem states to 2050 will be undertaken. Research on snow, the geobiology of deep weathering, the roles of slope aspect, and the use of cosmogenic radionuclides connects BcCZO to other CZOs across the country. In addition to training graduate students and post-docs, BcCZO will engage secondary students and teachers in CZ science, reach out to underrepresented minority students, and produce simulation modules for public education. Through partnership with CU Science Discovery, BcCZO will develop a Field Course for Colorado secondary teachers, a Mountain Research Experience for high school students, and offer traveling School and Community science programs. A graduate researcher will transform CZ models into interactive simulations, tested by Science Discovery students and teachers, and contributed to the Science Education Resource Center (SERC).