Tag Archives: southwest

Southwest Regional Warming Likely Cause of Pinyon Pine Cone Decline, Says CU Study

Creeping climate change in the Southwest appears to be having a negative effect on pinyon pine reproduction, a finding with implications for wildlife species sharing the same woodland ecosystems, says a University of Colorado Boulder-led study.

The new study showed that pinyon pine seed cone production declined by an average of about 40 percent at nine study sites in New Mexico and northwestern Oklahoma over the past four decades, said CU-Boulder doctoral student Miranda Redmond, who led the study. The biggest declines in pinyon pine seed cone reproduction were at the higher elevation research sites experiencing more dramatic warming relative to lower elevations, said Redmond of CU’s ecology and evolutionary biology department.  (more…)

Read More

UA Partners with Saudi Arabia to Create Sustainable Farming Systems

Faculty members from the UA College of Agriculture and Life Sciences are teaming up with partners at King Abdullah University of Science and Technology in Saudi Arabia to create the Desert Agriculture Research Institute.

Food, clean water and energy – our planet is challenged to meet these basic needs, especially in the harshest environments.

To help solve these global problems, faculty members from the University of Arizona College of Agriculture and Life Sciences are teaming up with partners at King Abdullah University of Science and Technology, or KAUST, on the Red Sea Coast, north of Jeddah, Saudi Arabia.

The state-of-the-art, progressive public university has turned to the UA – a leading institution in arid lands studies – for expertise in the creation of the Desert Agriculture Research Institute. (more…)

Read More

Droughts are Pushing Trees to the Limit

Droughts in the Southwest made more severe by warming temperatures are putting plants in stressful growing conditions, a new study has found, identifying an increasingly water-thirsty atmosphere as a key force that sucks moisture from plants, leading to potentially higher stress – especially in mid and low elevations.

As temperatures rise and droughts become more severe in the Southwest, trees are increasingly up against extremely stressful growing conditions, especially in low to middle elevations, University of Arizona researchers report in a study soon to be published in the Journal of Geophysical Research Biogeosciences.

Lead author Jeremy Weiss, a senior research specialist in the UA department of geosciences, said: “We know the climate in the Southwest is getting warmer, but we wanted to investigate how the higher temperatures might interact with the highly variable precipitation typical of the region.” (more…)

Read More

Mesquite Trees Displacing Southwestern Grasslands

Mesquite trees and woody shrubs are better adapted than grasslands to a Southwestern climate predicted to shift toward higher temperatures and greater variability in rainfall, UA ecologists have discovered.

As the desert Southwest becomes hotter and drier, semi-arid grasslands are slowly being replaced by a landscape dominated by mesquite trees, such as Prosopis velutina, and other woody shrubs, a team of University of Arizona researchers has found.

In a “leaf-to-landscape” approach, the team combined physiological experiments on individual plants and measurements across entire ecosystems to quantify how well grasslands, compared to mesquite trees and woody shrubs, cope with heat and water stress across seasonal precipitation periods. (more…)

Read More

Uncertain Future for Joshua Trees Projected with Climate Change

FLAGSTAFF, Ariz. — Temperature increases resulting from climate change in the Southwest will likely eliminate Joshua trees from 90 percent of their current range in 60 to 90 years, according to a new study led by U.S. Geological Survey ecologist Ken Cole.

The research team used models of future climate, an analysis of the climatic tolerances of the species in its current range, and the fossil record to project the future distribution of Joshua trees. The study concludes that the species could be restricted to the northernmost portion of its current range as early as the end of this century. Additionally, the ability of Joshua trees to migrate via seed dispersal to more suitable climates may be severely limited. (more…)

Read More

Drier Conditions Projected to Accelerate Dust Storms in the Southwest

MOAB, Utah — Drier conditions projected to result from climate change in the Southwest will likely reduce perennial vegetation cover and result in increased dust storm activity in the future, according to a new study by scientists with the U.S. Geological Survey and the University of California, Los Angeles. 

The research team examined climate, vegetation and soil measurements collected over a 20-year period in Arches and Canyonlands National Parks in southeastern Utah. Long-term data indicated that perennial vegetation in grasslands and some shrublands declined with temperature increases. The study then used these soil and vegetation measurements in a model to project future wind erosion.  (more…)

Read More