CAP-2 proposes to extend long-term study of central Arizona and metropolitan Phoenix, a desert region supporting agricultural and urban/suburban land uses while undergoing rapid urbanization and population growth. CAP studies human drivers and feedbacks of ecological change. Previous work concentrated on the central themes of urbanization patterns and processes altering the city's ecological conditions and surrounding environment, and ecological feedback-social system interactions. CAP-2 reorganizes the program into five new Integrative Project Areas (IPAs) to aid in the explicit inclusion of socioeconomic drivers and feedbacks: 1) land-use and land-cover change, 2) climate and ecosystem dynamics, 3) water policy, use and supply, 4) material flux and socio-ecosystem response, and 5) human control of biodiversity. The modus operandi for long-term monitoring, experiments, information management, site management, network participation and education/outreach was established during CAP-1 pilot projects. Projects continued into CAP-2 include: long-term monitoring at 200 sites across CAP; historical analyses of land use; classification of land cover; documentation of change in land cover and use; river monitoring above and below the city; and establishment of intensive sites for in-depth climatic, ecological, and social surveys and experiments. Three long-term experiments will be continued and a fourth initiated (a long-term factorial N+P fertilization along a deposition gradient). The recently established North Desert Village "experimental suburb" will be the first experimental study of its kind, with manipulations of vegetation types and irrigation methods alongside examination of people-ecological environment interactions at the neighborhood scale.
Broader Impacts. The broader impacts of the proposed CAP project include: 1) raising the profile and awareness of urban ecology in both science and society, 2) contributing to education and outreach at all levels, 3) producing and maintaining a comprehensive, long-term database of ecological and social variables for a rapidly changing socio-ecosystem, and 4) promoting knowledge exchange with community and governmental decision makers. Ecology Explorers, CAP LTER's K-12 education-outreach program, will see continued growth while maintaining its existing diversity of programs and working toward district-wide adoption of the Ecology Explorers curriculum. Two new programs are introduced to promote undergraduate involvement, including the Communities of Research Scholars and Interns. CAP LTER participants developed the ASU IGERT program in urban ecology and will continue to support graduate participation in research, introducing summer support for independent research in CAP-2. Information management will continue to develop innovative new techniques to preserve the long-term integrity and accessibility of the CAP LTER database. Finally, for knowledge exchange, CAP LTER will continue to partner with several related projects and initiatives in science-policy outreach relating to the urban environment.
The Central Arizona-Phoenix Long-Term Ecological Research (CAP LTER) program has completed twelve years of research focused on a 6,400 km2 study area in central Arizona encompassing metropolitan Phoenix, rapidly disappearing agricultural land, and the surrounding Sonoran Desert. Our research involves hundreds of faculty and staff scientists, undergraduate students, and graduate students from more than a dozen disciplines. Together, we have contributed to the new discipline of urban ecology and have promoted the importance of interdisciplinary research in understanding the ecology of the city as evidenced by over 300 publications funded through the National Science Foundation’s LTER program and $44 million in additional, leveraged funding. The Phoenix metropolitan region has changed dramatically over time with much urban growth occurring over the last forty years. We have documented land use and land cover change using remote sensing techniques, and our scientists have sought to understand the consequences of this change. Our research has shown that some common urban species of birds, such as pigeons and grackles, take over habitat from native bird species that otherwise might be able to survive in the city. We also found that urbanization increases the number of types of plants that grow in the city compared to the desert as homeowners in the Phoenix region have introduced many non-native plant species to create an "urban oasis." In general, the addition of irrigation water to the landscape in Phoenix has altered the desert ecosystem, allowing many non-native and some native species of plants and animals to thrive. Even residents who try to mimic the desert with desert-looking landscapes cannot fully replicate the ecological functioning of the native desert; urbanization appears to alter the desert forever. Still, our surveys have found that the vast majority of urban residents view the Sonoran desert as a special place, and most see value in preserving desert wildlands. Urbanization has made some areas of the city much hotter than the surrounding desert, and this becomes a particular problem during summer when daytime high temperatures are well in excess of 100°F for months at a time. Our research has indicated that neighborhoods with a high percentage of minority, low-income, and elderly residents are at the greatest risk for exposure to high heat but that vegetation, such as shade trees, may provide relief from heat. While the Phoenix region has changed significantly, becoming more urban and much less agricultural, remnants of the agricultural past remain in the soil chemistry and also in soil formations and plant types still present in the location of 1,000 year-old Hokoham agricultural fields. Water availability and control have been critical factors in the settlement and urbanization of the region. Outdoor irrigation accounts for most of the water used in the Phoenix area, although the amount used varies dramatically by socio-economic status. Our research found that policymakers are significantly less concerned than the lay public or scientists about regional water-use rates while the lay public tends to blame other people for water scarcity, and scientists stress the need to control demand for water. As the urban extent has grown, city planners have designed specific ecosystems to deal with problems such as flooding and stormwater removal as well as to restore riparian habitat. We have examined these ecosystems to better understand how they work, discovering that they fulfill a number of ecosystem functions, some intentional and some not. Residential yards are also designed ecosystems, and our research has focused on both the ecology of these yards and the household decision-making that goes into shaping them. We have found that socio-economic status, values, social norms, and homeowner associations all influence landscaping decisions that have implications for species diversity in the city as well as water use. Finally, we communicate our knowledge about the ecology of the Phoenix region to school children through our award winning Ecology Explorers program, which has designed lesson plans to allow students to replicate our research in their schoolyards and analyze our research data.
