In many parts of the world, including the southwestern United States, lands once covered by grass are starting to look like deserts. As scientists learn more about why this is happening, they are starting to realize that these lands do not always become deserts. There are other possible outcomes, such as habitats with lots of shrubs and with plants that spread rapidly from elsewhere (non-native or “invasive” species). The goal of this project is to test new ideas about what causes these sorts of changes. Scientists at universities and at the United States Department of Agriculture (USDA) will work together to run experiments and collect data in the Chihuahuan Desert, where a lot can be learned from areas that have been changing in different ways. The study is especially valuable and unusual because it has been going on for more than 100 years. Scientists are not only interested in why changes are taking place but also in how those changes affect “ecosystem function,” which is the way that plants and animals grow, multiply and interact with each other and with the environment. Results will help scientists around the world predict and prevent harmful impacts of environmental change. Part of the project will involve training students to do research and become scientists. Many of these students will be from nearby Hispanic-serving universities. Scientists on the project will also reach out to students and teachers at local elementary, middle and high schools. They will become engaged through exciting lessons, field trips, and workshops. Discoveries from this project will be shared through workshops, talks, websites, and mobile phone Apps.
Chihuahuan Desert landscapes exemplify the ecological conditions, vulnerability, and management challenges in arid and semi-arid regions around the world. The overall goal of the Jornada Basin Long-Term Environmental Research (LTER) Program is to understand and quantify the key processes and factors that generate alternative states in drylands, and to predict future states and their consequences for the provisioning of ecosystem services. Based on long-term databases from Agricultural Research Service of the USDA beginning in 1915, studies will include four types of dynamics: (1) a shift from perennial grasslands to desertified shrublands, (2) a reversal to grassland states, (3) transitions among shrub-dominated states, and (4) invasion by non-native grasses. These transitions have profound implications for the processes reflected in the 5 core LTER research themes. In this LTER renewal project, the “trigger-feedback-heterogeneity” framework for understanding and predicting the dynamics of state changes in dryland landscapes will be expanded to contribute to emerging ecological theory on: (a) alternative states and resilience, (b) ecosystem sensitivity to global change, and (c) cross-scale interactions. The novel approach will integrate knowledge and long-term data on: (1) biological processes, (2) spatial heterogeneity in the soil-geomorphic template, and (3) variability in environmental drivers drawn from multiple lines of evidence (i.e., observations, experimental manipulations, analytical and numerical models, products from imagery, conceptual model reasoning, and theory). The information management system will be expanded into a Data Science Integrated System of drylands that will allow Jornada results to be translated to other locations in the Chihuahuan Desert and to drylands globally. LTER research will result in: (1) new understanding of state changes that lead to theory development, testable hypotheses, and new experiments; (2) accessible data, derived data products, and visualization tools applicable at multiple scales; and, (3) explanatory and predictive relationships among drivers, patterns, and processes that can be used to (4) predict dynamics of alternative states at new locations or future conditions with assessments of their impacts on ecosystem services.
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.
