Montrose - Daily Press

MONTROSE — Captured in the imagination, the adobe badlands look like the backs of sleeping dinosaurs dusted with golden sand.

In reality their light gray color and sparse vegetation mask the enormous role these Mancos shale, or black shale, landscapes play in issues important to all area residents.

The adobes, salt- and selenium-containing remnants of an ancient sea, are the focal point of water quality measures, endangered species survival and centuries of recreational delight — reasons which prompted local land managers several years ago to enlist the help of scientists in uncovering the adobes’ mysteries.

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“We had a lot of questions about how to best manage the Mancos shale, so we employed the U.S. Geological Survey to study those aspects of the shale for us, to help us characterize it better, to help us manage the different activities going on on the shale,” said Bureau of Land Management hydrologist Dennis Murphy.

Findings from five years of research, with the primary sites in the Gunnison Gorge National Conservation Area, were handed over in March to land managers. BLM Gunnison Gorge NCA Manager Karen Tucker said the staff may overlay use, vegetation and data maps, and from there discern whether there are differences between the data and objectives for the area.

While it will take some time to sort through all the findings, some are already providing insight into the adobes.

Scientists found cryptogamic, or biological, soil crusts all over the NCA’s adobes. These crusts are formed by living organisms, such as cyanobacteria and microfungi, and their by-products, noted USGS research ecologist Jayne Belnap. Some of the organisms secrete mucus as a means of protection from sharp sand grains. Like glue, the mucus binds together particles to form a crust effective in absorbing rainfall and preventing soil erosion, which helps to keep selenium and salt from being carried off from the Mancos to rivers and canals.

The stark difference between disturbed and undisturbed Mancos shale landscapes is effectively illustrated in a cryptogamic map of the area completed as part of the research. A half-mile-square area the BLM likely fenced sometime in the 1960s appears as a vibrant colored square on the map. When it rains, the difference is even more prominent, Murphy said.

When water hits mancos shale it percolates into the ground, carrying salt and selenium, until it hits a hard and tilted layer of mancos shale. The water slides down the shale and into drain ditches and rivers, said Marc Catlin, manager of the Uncompahgre Valley Water Users Association. One-third of the 70,000 to 75,000 acres of land irrigated by the association is in Mancos shale.

The USGS tested for selenium content in efflorescent salts collected from sites in and adjacent to the NCA. The highest selenium contents (150 parts per million) occurred in an area outside the NCA typically flooded with irrigation water. The highest NCA selenium content was 70 ppm.

The problem with selenium is that some evidence suggests it interferes with the reproduction of endangered fish species (such as razorback sucker and Colorado pikeminnow) and water fowl, Catlin said. “We (humans) can discharge selenium where in the lower life forms, it’s a bioaccumulator and it becomes concentrated in the reproductive system,” he said. “That’s when the empty nests and misshapen fry show up.”

Rather than having the water seep into earthen ditches, the association began in 2000 to place plastic pipe down about 35 to 37 miles of its ditches. Samples collected by the USGS pre- and post- piping showed an immediate 25 to 30 percent reduction in the movement of selenium, Catlin said.

These pollutant control measures, which have the added benefit of water conservation, are guided and supported by both the U.S. Bureau of Reclamation’s Salinity Control Program and the Clean Water Act.

“(It’s) also important to the people of Montrose and Delta counties because they don’t want to lose those (endangered) species,” Catlin said. “And if we find a way of cleaning up the water without the agricultural people having to pay for it, then everybody wins. So far it’s been working.”

Scientists studied soil chemistry throughout the NCA in an effort to characterize the habitats of endangered plants such as the clay-loving wild buckwheat, a pink-flowered plant found only on the adobe hills of Delta and Montrose. This information may prove useful in developing species and habitat protection and recovery plans, Tucker wrote.

Other research looked at the depth of the Mancos formations and found it to be up to a mile thick in some intact areas, Murphy said. This and countless soil samples may help determine why some areas have elevated salt and/or selenium levels.

Time will tell what all these characterizations might mean to the area’s management.

“These areas have been impacted for many, many years. Recovery is probably not going to happen,” said Tucker. “... We can manage these areas, and I think we’ve been very successful in the (nearly) 10 years since designation (of the NCA).”

Prior to creation of the Gunnison Gorge NCA in 1999, there was controversy over whether the area should be designated, said Tucker. It was eventually named a national area with managed traditional uses, including off-highway vehicles. Of the NCA’s 22,000 acres of previously open management areas, 900 acres remain open and the rest is limited to use on managed routes. Support from local businesses, such as the Davis Service Center, and the Colorado State Parks Trails Program allowed for the creation of an off-road vehicle training area.

On any given day of the week, off-road enthusiasts can be seen rolling up and down the adobes slopes. The area attracts people like Iowa-resident Lyn Coulter, who has for the past 10 years, three times a year, traveled to Montrose to ride the area.

“It is one of the most fantastic places to ride a motorcycle that we have ever seen. The area is just an absolute fun place to ride in,” Coulter said. “We ride only on the trails and are very careful not to damage any of the surrounding areas around the trails.”

On a broader level, Tucker said research of the landscapes helps BLM managers and the public understand landscape level changes over time as well as the effects of surface-disturbing activities on Mancos areas.

“Our job is to balance the use and we can’t do it with one eye shut, for all kinds of reasons,” said Tucker “How do we manage use? This is where the USGS research comes in.”

From “The Awesome ‘Dobie Badlands by Muriel Marshall:

There are countless other stories about the people who lived in the ‘dobies but, like the ditches and cellar holes, they are blurring away.

It was with this thought in mind that Uhlan Austin autographed the gate to his badlands homestead.

“The ‘dobies are full of mysteries and unanswered questions. You see the dead stub of an orchard tree, rocks laid in a square, trace of a road that goes nowhere. You keep wondering, Who did this... Why did he come... Where did he go...

“I got to thinking about people years from now prowling around my homestead here and wondering who was fool enough to like living way out here in the silence, so I just decided I’d leave something they could get a handle on — my name welded in iron on an iron gate.

“Dry as it is out here, it should just about last forever.”

The U.S. Geological Survey’s Mancos Shale Landscapes Project is a multi-disciplinary project covering the Upper Colorado River Basin and involving the U.S. Fish and Wildlife Service, Bureau of Reclamation, Gunnison Basin Selenium Task Force, Colorado River Basin Salinity Control Forum and Grand Valley Selenium Task Force.

For more information on the project, go to: http://minerals.cr.usgs.gov/projects/mancos_shale/index.html

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