Waterholes, boinkas, mallines …. wetlands in drylands (WiDs) have highly diverse characteristics and an equally diverse set of local and regional names. This page will highlight some of the more unusually-named WiDs. We welcome input from people who may have greater experience with some of these WiDs, and who may therefore be able to provide some insight into the origin and application of the terms than might otherwise be obtained from published papers or reports.
But first, a more fundamental question: where did the term ‘wetlands in drylands’ originate?
According to Moss (1980), the term ‘wetlands’ – as opposed to ‘wet lands’ – arose from a classification scheme devised in the 1950s by the United States Fish and Wildlife Scheme (USFWS). Thereafter, the term has become widely adopted as an all-inclusive term for describing lands that are ephemerally, seasonally, or permanently inundated by fresh and/or salt water, including in the title of academic textbooks and journal papers. [Nb. the Merriam-Webster online dictionary states that the first known use of ‘wetland’ was in 1669 but provides no supporting evidence, and may not be distinguishing between use of ‘wet land’ and ‘wetland’].
The term ‘drylands’ – as opposed to ‘dry lands’ – is proving harder to pin down. Here too, the term is likely to have arisen in American English, possibly in the 1950s in the arid lands programme papers of the United Nations Educational, Social and Cultural Organization (UNESCO). As an umbrella term for describing land that is subject to high but variable degrees of aridity, it also has since become widely adopted, including in the title of academic textbooks and journal papers. [Nb. the Merriam-Webster online dictionary states that the first known use of ‘dryland’ is in 1893 but again provides no supporting evidence].
As far as we are aware, the first known use of ‘wetlands in drylands’ in the title of an academic journal paper was by Scoones (1991) but if other information is forthcoming, we stand to be corrected.
Moss, D. 1980. Historic changes in terminology for wetlands. Coastal Zone Management Journal 8: 215-225.
Scoones, I. 1991. Wetlands in drylands: key resources for agricultural and pastoral production in Africa. Ambio 20: 366–71.
A billabong is a seasonal or intermittent wetland formed within an abandoned meander loop (or, oxbow lake) adjacent to the main channel of a river. Some billabongs in arid regions take the form of waterholes which occur at the confluence of two smaller channels and terminate shortly thereafter. The term billabong loosely translates to “dead rivers”, reflecting the boom and bust cycles of wetting and drying in the arid interior of Australia.
[contribution by Tim Ralph, February 2017]
Ciénega (southwest USA)
‘Ciénega’ (alternatively spelled ‘ciénaga’) is a regional, Spanish term which describes mid-elevation (~ 1000–2000 masl), marshy areas that occupy headwater valley bottoms in the otherwise arid southwest USA. Most ciénegas have developed over the past 8000 years (Holocene) through fine sediment accumulation atop older (Pleistocene) deposits.1 Accordingly, ciénegas have formed on headwater channel floodouts and small floodplain pockets and may also occur on parts of relict terraces, on floodplains, and within channels. These wetlands are typically maintained by groundwater (springs and seeps) but are commonly supplemented by surface flows from adjacent stream channels.1,2 Associated vegetation communities include aquatic, semiaquatic, and riparian distributions of sedges, rushes, and grasses with few trees.2
Many ciénegas have undergone cycles of erosion and deposition linked to changes in climate over the past several thousand years.1 Major ciénega erosion occurred after colonial expansion through the western USA in the 1800s.3 Ciénegas that once spanned entire valley bottoms developed extensive gullies, regionally termed ‘arroyos’, which lowered groundwater levels and degraded the wetlands.1,2,3 The cause of this widespread erosion is still debated but has been attributed to a combination of changes in precipitation and overgrazing.3 Presently, very few pristine ciénegas exist, and most contain some form of gully or channel incision.2,3 Various management strategies have been used to restore eroded ciénegas but with mixed results.1,3
1Cole, A., Cole, C., 2015. An Overview of Aridland Ciénagas, With Proposals for Their Classification, Restoration and Preservation. The New Mexico Botanist, 4, 28-56.
2Hendrickson, D.A., Minckley, W.L., 1984. Cienegas: Vanishing climax communities of the American Southwest. Desert Plants, 6, 130-176.
3Minckley, T.A., Turner, D.S., Weinstein, S.R., 2013. The relevance of wetland conservation in arid regions: A re-examination of vanishing communities in the American Southwest. Journal of Arid Environments, 88, 213-221.
[contribution by Peyton Lisenby, July 2018]