Jornada Trails

Contents:

• Jornada Renewal Proposal Submitted
  
• Reconnaissance Images Show Mesquite Invasion
  
• New Facilities for Jornada LTER
  
• 2000 Friends of the Jornada Symposium
  
• Book Review: A Natural History of the Sonoran Desert
  
• Featured Investigator: Dave Lightfoot
  

Jornada Basin scientists worked feverishly through the month of January to prepare the renewal proposal for the National Science Foundation.

The proposal, requesting $4,200,000 of funding for the next six years, would represent the fourth funding cycle for the Jornada Basin LTER--an effort that began under Walt Whitford’s direction in 1981.

Capitalizing on work accomplished during the past dozen years, in which Jornada LTER scientists focused on plant- and patch-scale processes, the new proposal stresses the importance of understanding linkages between landscape units in desert ecosystems.

For instance, with infrequent but intense rainstorms, precipitation received on mountain slopes and their upper piedmonts may run off to lower landscape positions, where it infiltrates the soil and adds to local soil water. In water-limited regions, this regional redistribution of water may have as much effect on plant growth as the local soil patchiness that characterizes desert shrublands.

With renewed funding, LTER scientists will examine the transport of nutrients in runoff waters and wind erosion, which both move materials across the landscape. The transport of water and soil nutrients across the landscape is often affected by land-management decisions, such as grazing. Thus, a better understanding of the importance of ecosystem linkages will help explain the causes and consequences of desertification in drylands worldwide.

This renewal effort was spearheaded by Laura Huenneke, Kris Havstad, Debra Coffin Peters and Curtis Monger at New Mexico State University. These principal investigators are joined by nine other scientists, including Bill Schlesinger (Duke University), who has led the Jornada Basin LTER since 1991. New members of the LTER team include Jeffrey Herrick and Al Rango, both scientists of the Agricultural Research Service (ARS).

Central to the LTER program is the development, maintenance, and use of long-term datasets to understand ecosystem function. Thus, the existing 10-year record of net primary production from three sites, representing different landscape positions, in each of five ecosystems will be central to an analysis of the response of these ecosystems to landscape-scale transport.

Other long-term studies, including Dave Lightfoot’s census of arthropod and rodent populations, will also continue during the next cycle of LTER funding.

Al Rango will apply his expertise in remote sensing to help understand the patterns of wind and water erosion in grassland and shrubland habitats. Deb Coffin Peters will use the spatially-explicit vegetation model, ECOTONE, to assess the importance of landscape transport to desert ecosystem function.

With enthusiasm running high, the Jornada Basin LTER workers wait anxiously for word of a favorable reaction to their proposal to the National Science Foundation.

Jornada Basin LTER researchers have received the first set of nearly 40 pictures taken from military reconnaissance satellites between 1964 and 1991. The images were provided by the National Imagery and Mapping Agency at the request of a panel of scientists, known as MEDEA, who advise the intelligence community about ways in which its assets can be used to solve environmental problems. The photos were released by President Clinton in October 1999 (Science 286: 34, 1999).

Even with a brief examination of a few of the early photos, Dr. Sarah Goslee, a postdoctoral researcher with the Agricultural Research Service in Las Cruces, can see an increase in the total area occupied by mesquite. Over time, Sarah notes, the photos show considerable dynamics in the establishment of young mesquite. "Mortality in small shrubs is high, but once shrubs reach a threshold size, they are likely to persist for long periods."

The use of declassified images at the Jornada parallels a study by MEDEA member and LTER scientist William Schlesinger that investigates changes in the woody vegetation in southern Sudan from 1943 to 1994 (Global Change Biology 2: 137–141, 1996). He found little evidence for the loss of woody plants in areas not directly affected by humans.

Working with Al Rango, Sarah will compare the military satellite images to current multispectral images and aerial photography of the Jornada Basin LTER.

by Kris Havstad, USDA

Within the next two years, the offices of the Jornada Basin LTER will move into a new federal building on the west side of the New Mexico State University campus. Constructed for the USDA Jornada Experimental Range, this $6.7 million, 29,000 square-foot facility will house about 45 employees of the Agricultural Research Service, the LTER program, and NMSU, as well as collaborators from other state and federal agencies.

Construction on the two-story building is scheduled to begin in August 2000, with completion expected late in 2001. Approximately one-half of the building will be laboratories, one-third will be offices, and the remaining portion will include work areas (for activities such as data processing and GIS) and a 1450 square-foot conference facility. New science staff will be hired upon completion of the building.

Be sure to register for the annual Friends of the Jornada Symposium to be held in Room 111 of the Chemistry Building on the New Mexico State University campus on Thursday, July 13, 2000. A full day of informal research presentations will be followed by the traditional, and now famous, evening barbecue--featuring the 5Bs--at the USDA Headquarters Ranch. This is the Tenth Annual Symposium, and we expect that it will once again provide a lively exchange of ideas and data on the Chihuahuan desert environment. A registration fee of $10 covers the costs for refreshment breaks during the symposium, as well as the evening barbecue.

For more information or to register, contact:

   Valerie La Plante
   USDA/ARS Jornada Experimental Range
   P.O. Box 30003, MSC 3JER
   New Mexico State University
   Las Cruces, N.M. 88003 

Or, register via email to: vlaplant@nmsu.

by William H. Schlesinger

Duke University

Edited by Steven Phillips and Patricia Wentworth Comus (Arizona-Sonora Desert Museum Press/The University of California Press, $55 cloth, $24.95 paper)

At the Arizona-Sonora Desert Museum outside Tucson, the native flora and fauna of the desert can be seen in natural settings with excellent interpretation. In this volume, the staff and docents of the Museum have compiled observations and notes on the natural history of the Sonoran desert and the creatures that are so marvelously adapted to life in an arid world.

The first part of the book examines the climate, soils, and geography of the Sonoran desert, as a natural arena housing a variety of desert biomes. Remembering some of my own experiences in the region, I found the chapters on desert storms, light, and soils a particular delight to read.

The second half of the book offers a systematic treatment of the common plants and animals, detailed in individual chapters authored by local authorities. The book contains 32 exquisite full-color photographs of Sonoran desert habitats in the U.S. and Mexico.

I found Gary Nabhan’s chapters on human impact poignant. The rich biodiversity of the desert is lost "as uninformed people who believe the Sonoran Desert to be a wasteland unknowingly turn it into one." This book will reduce the ranks of the uninformed if they are willing to appreciate its message.

It is a familiar sight to find Dave Lightfoot patiently searching plants for grasshoppers or checking live traps for rodents in the Jornada field plots. Dave has a long association with the Jornada Basin LTER, having completed his Ph.D. in 1988 at NMSU, where he studied the arthropod fauna on creosotebush.

Now based at the University of New Mexico, Dave is responsible for all consumer studies in the current LTER program at the Jornada, and he fosters communication and interaction with the Sevilleta LTER site to the north.

Dave’s original interests were in the biology of orthopterans (grasshoppers and their kin), but he has also improved our monitoring of small mammals, lagomorphs (rabbits), and reptiles. Currently, he is funded by NSF in a cross-site study establishing small mammal exclusion plots at the Sevilleta, the Jornada, and the Mapimi Biosphere Reserve in Mexico. This work examines changes in vegetation and soil in response to the elimination of the activities of these important animals.

Dave is involved in a wide array of other projects. He is working with Laura Huenneke on a USGS-funded study to examine the response of Chihuahuan desert communities to regional changes in land use and climate. At the Sevilleta he supervises arthropod studies and several other cross-site projects, and he continues to survey arthropods throughout the Southwest, from Baja California to Bandelier National Monument. At UNM, Dave teaches (with Bob Parmenter) a very popular course in desert ecology, with the pleasant task of traveling with students each year to long-term desert research sites across the Southwest.

The Jornada LTER program can thank Dave Lightfoot for establishing the basic framework of our database and documentation system during the crucial period when NSF first demanded careful data management at each LTER site. All Jornada Basin scientists benefit from Dave’s generosity--ranging from teaching us how to identify ant colonies based on nest appearance to leading some of our most important cross-site studies.