Saturday, 7 May 2016

flood depth and duration for some bryos in a sinkhole

me again.

In my day job I am a jack of all trades, however sometimes I look at karst aquifers. I have just published an article on measuring flow into a doline / sinkhole. Anyhow I managed to scrape in some flood depth and duration data for the bryos living at the base of the sinkhole including; Gymnocolea inflata, Sphagnum denticulatum, Warnstorfia fluitans and Mnium hornum. Interestingly (or not you may tell me) is that they are all tolerant of flood depths of up to 6m for durations of 20-40% of the study period (a year). The crux of the paper was the actual hydrology however I made a call that these small ephemeral ponds are under-recorded and should be considered as wetlands? Who knows?
Maybe there is someone out there who wants to survey some upland dolines ? I hope to be supervising a MSc looking at dolines on Mynydd Llangynidr this year, so if anyone is interested, or you have students or others asking for experience, then ill be messing around up there in the very near future, im sure there will be room for one more !

Right off to a Bar-b-q, time to pack sunglasses, shorts, raincoat and umbrella.

Full paper is free to download at this link


  1. I enjoy your posts Gareth - it's nice that you come at things from a different angle to the rest of us. I am surprised at the Mnium - I always think of that as a rather dry ground species (it does occur on riverbanks but I usually see it high on the bank where inundation is less common).

  2. Good im glad im not being a pain with my random hydro focused posts ! Yes others are often in wet places so no surprise, but hopefully its of some worth to show at least one species is a bit more tolerant to flooding than normally perceived :)

  3. I do see Mnium hornum on ditch sides in peatlands quite regularly, usually where deeply shaded by overhanging Molinia. I suspect those colonies are inundated occasionally. Nevertheless, the prolonged deep inundation in Gareth's doline is a bit of a surprise. Atrichum crispum might perhaps be more likely with those associates, and isn't a well-known species, but I don't know who did the IDs.

  4. It is possible I could be on Llangyidr / llangattock a fair bit this summer ... I collected a couple of things from a regularly flooded sink there lad year, but have misplaced packet somewhere ... I'll be having a big clear out this summer so hopefully it will turn up ... There was a scrap of a Riccia which will probably turn out to be huebeneriana. If you contact me at work we should be able to sort a visit.

  5. Sam, IDs confirmed by Jon Graham !