A CRA representative attended the meeting and presented the message to the Open Space Board, as part of the public comment period, that riparian areas require protection and stewardship:

The Mission of the CRA is to promote the conservation, restoration and preservation of Colorado’s riparian areas and wetlands. The goals we use to achieve our Mission are:

• To foster a practical and scientific understanding of riparian areas and wetlands in Colorado.
• To promote sound management of riparian areas and wetlands in Colorado through demonstration and education.
• To promote communication and coordination among all people interested in riparian areas and wetlands in Colorado.

The CRA Board and Membership has a diverse mix from policymakers to practitioners and land managers to ranching families. Within this broad range of expertise and background is a consensus that riparian areas require protection and stewardship because they are especially:

• Rare
• Sensitive, and
• Irreplaceable

Similar consensus is seen on a broader level throughout local, State, and Federal agencies, and by researchers and practitioners, alike. (CRA rep presented 5 articles from diverse entities to demonstrate the consensus).

Succession towards something closer to a ‘climax’ community fits your description and is often seen where stream corridors have been relatively undisturbed by flooding or fire for a very long time. Sustained cattle pressure on these areas may help this along, to a degree.

Here is the link to the article in the Durango Herald

Also the link to the USGS, Forest Service, and Bureau of Reclamation joint report, which is the report referenced by the article

Riparian communities are often referred to as “ribbons of green” or “the green line” in the arid Western U.S., since in many landscapes, the riparian areas along watercourses provide the only visible green vegetation.

CRA provided a list – contact CRA for more information.

Quotes include: (Contact CRA for more information.)

“Riparian areas comprise less than one percent of the land area of most western States, yet up to 80 percent of all wildlife species in this region of the country are dependent upon riparian areas for at least part of their life cycles”. Robert H. Wayland III, EPA, from Congressional Testimony on June 26, 1997.

Though estimates vary, it is generally agreed that riparian ecosystems comprise less than 1% of the surface area in the 11 western United States (Cooperrider et al. 1986; Ohmart 1996).

Riparian communities in the Western U.S. are the most productive habitats in North America (Johnson et al. 1977), and provide irreplaceable wildlife habitat for breeding, wintering, and migration.

An estimated 75% of the vertebrate species in Arizona and New Mexico depend on riparian habitat for some portion of their life history (Johnson et al. 1977).