Drought

Drought, hotter temperatures, and insect outbreaks are affecting dryland ecosystems across the globe. Pinon-juniper (PJ) woodlands are a widespread vegetation type common to drylands of North America, which have been hit particularly hard by a warming climate. Specifically, mass tree die-off events are transforming PJ woodland structure, composition, and distributions. This project aims to...

Within areas of overlapping sagebrush and pinyon-juniper ecosystems, wildlife populations are declining due to habitat fragmentation and degradation, changing climate, and human development. However, management to bolster species associated with one ecosystem may result in negative consequences for species associated with the other. Thus, land managers are challenged with balancing which system to...

For over 30 years we have monitored the ecosystem dynamics of the mesas and mountains of northern New Mexico, co-located with mangers. We use a place-based science approach, defined as “science that is founded on long-term, repeated, field data and observations, as well as traditional knowledges, and regularly engages local managers and community members.” This approach enables us to provide land...

Ecological impacts of drought have been rarely considered compared to agricultural or municipal water supply effects.

Aquatic Systems Branch scientists analyze rings of riparian trees relating tree growth and establishment to historical flow. We then use the tree rings to reconstruct the flow in past centuries. Flow reconstructions discover the frequency and magnitude of past droughts and floods—information that is essential for management of rivers and water supplies. We also use downscaled climate projections...

Drought is killing riparian trees along many rivers in the western United States. The cause can be increasing temperature or decreasing precipitation, flow or water-table elevation. At multiple locations we are relating water availability to physiological measurements of tree survival and water stress, such as ring width, carbon stable isotope ratio and branch hydraulic conductivity. These...

Riparian ecologists at the Fort Collins Science Center study interactions among flow, channel change, and vegetation along rivers across the western United States and worldwide. Our work focuses on issues relevant to the management of water and public lands, including dam operation, climate change, invasive species, and ecological restoration. Investigations take place on a range of scales. For...

The Wyoming Landscape Conservation Initiative (WLCI) addresses effects of land-use and climate changes on Southwest Wyoming’s natural resources. In partnership with twelve Federal, State, and local natural resource agencies, and non-governmental organizations– FORT and ten other USGS centers are conducting dozens of integrated science projects to assess the status of Southwest Wyoming’s natural...

The Wyoming Landscape Conservation Initiative (WLCI) addresses effects of land-use and climate changes on Southwest Wyoming’s natural resources. In partnership with twelve Federal, State, and local natural resource agencies, and non-governmental organizations– FORT and ten other USGS centers are conducting dozens of integrated science projects to assess the status of Southwest Wyoming’s natural...

Western Mountain Initiative (WMI) is a long-term collaboration between FORT, WERC, NOROCK, USFS, NPS, LANL, and universities worldwide to address changes in montane forests and watersheds due to climate change. Current emphases include altered forest disturbance regimes (fire, die-off, insect outbreaks) and hydrology; interactions between plants, water, snow, nutrient cycles, and climate; and...

Natural climatic variability, including episodic droughts, has long been known to trigger accelerated tree mortality in forests worldwide, including in the Southwest U.S. Scientific understanding of the process drivers and spatial patterns of tree mortality is surprisingly limited, constraining our ability to model forest responses to projected climate changes. The onset of regional drought since...

High-severity crown fires in Southwestern dry-conifer forests — resulting from fire suppression, fuel buildups, and drought — are creating large treeless areas that are historically unprecedented in size. These recent stand-replacing fires have reset extensive portions of Southwest forest landscapes, fostering post-fire successional vegetation that can alter ecological recovery trajectories away...