Here is another possibility:
http://www.fastq.com/~jrschroeder/poop.htm
From their website:
The dirt is alive
Many visitors to Canyonlands are surprised when told to be careful where they walk...that the dirt here lives and the dirt here breathes. Cryptobiotic soil, a nutrient-rich crust, forms the most common ground-cover in Canyonlands and the surrounding area. Cyanobacteria, the main component of these soils, weave microscopic fibers around loose sand grains, binding them together and creating a stable environment in which seeds can germinate. When crushed, the soil's fibers are broken and the rate of wind and water erosion dramatically increases. Eventually, the nutrient content of the broken soil is reduced, leaving less habitat for vegetation.
Cryptobiotic soil takes decades to form. Footprints and tire tracks can last a lifetime and ruin the pristine atmosphere that many people find so remarkable about the back country. It is essential, for both ecological and aesthetic reasons, that all hikers remain on marked trails or other durable surfaces. These include rock or natural drainages. Avoid using shortcuts or "game" trails as these further the spread of impacted areas and rarely save time.
and
Human waste is a health hazard
In the desert, it is the sun's heat, not water, that has the greatest role in breaking down human waste. The dry climate of the high desert does not promote decomposition like forest or mountain soils. As a result, the buildup of human waste in the back country of Canyonlands has become a serious problem, especially in high use areas like designated sites and high-water camps along the rivers.
Whenever possible, human waste must be removed from the back country. To accomplish this, hikers, four-wheel drivers or boaters should use park-maintained vault toilets whenever they are available. Groups traveling along the rivers are required to bring and use their own cleanable, reusable toilet system.
Four-wheel drivers camping in the Maze or at the New Bates Wilson site in the Needles must provide their own cleanable, reusable toilet system as there are no vault toilets at these sites.
When backpacking, human waste should be buried in a "cathole" 4 to 6 inches deep, at least 300 feet away from any water source or major drainage. Avoid using locations too close to campsites or hiking trails. In Canyonlands, the best place to dig a cathole is beneath a pinyon or juniper tree where cryptobiotic soils do not form. It is helpful if the hole has some exposure to direct sunlight.
Toilet paper must be packed out as it will not decompose in this dry climate. Never burn or bury it. The burning of toilet paper can cause serious brush fires in the desert. Consider using natural alternatives to toilet paper such as smooth rocks or twigs.
So had you actually bothered to do any research you would already have had your answers. One as savvy as you are about everything backcountry should realize that different climates require different techniques.
