CAREER: Soil Pedogenesis, Agroecology, and Their Interactions

Humans affect soils through agriculture in several ways: removing nutrients, altering ground surfaces, changing vegetation, and so on. By changing the soil, people are also changing the future potential of agriculture on those soils. This project uses Hawai'i Island as a model system to understand how centuries of farming has impacted the soils. Hawai'i is an excellent study system because of the diverse soil types created by the combination of different aged lava flows and broad rainfall gradients, and because of the diverse agricultural strategies Hawaiian farmers used on the different soils. Such studies are extremely important today as the world grapples with agricultural sustainability. By learning about agricultural adaptation and the long-term sustainability of indigenous agriculture we can learn how to maintain agriculturally sustainable soils. This project will also train a significant number of undergraduate and graduate students, including Native Hawaiians, and will engage middle and high school students in Hawai'i in learning about the history of social and agricultural practices of their home.<br/><br/>This project builds upon a foundation of soil pedogenesis work in Hawai'i and leverages the relatively short time frame of human occupation (approximately one millennia) to understand anthropogenic impacts on soils in their entirety. Project data will advance knowledge of soil pedogenesis and biogeochemistry while using interdisciplinary methods to quantify pre-industrial human impact on soils within a framework of niche construction. The overarching hypothesis is that niche agroecological construction of pre-industrial agriculture in Hawai'i was highly dependent on interaction with and feedback to the biogeochemical environment. The research team will pursue five specific aims: (1) use soil, elemental, and isotopic analysis to characterize and map natural soil biogeochemistry; (2) map agricultural strategies using mixed methods of plant micro-remains, historical documentation, remote sensing, and geospatial modeling; (3) document and quantify human alteration of soils and biogeochemical cycling through soil science and biogeochemical modeling; (4) create predictive geospatial models of agroecological forms based on biogeochemical drivers; and (5) further situate findings within the biocultural restoration of Native Hawaiian socioecosystems. This award was co-funded by the Ecosystem Science Cluster (BIO/DEB) and the Archaeology Program (SBE/BCS).<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.