Showing posts with label tufa. Show all posts
Showing posts with label tufa. Show all posts

Sunday, 20 November 2016

...more of the same, but this time with a microscope




Hannah had the pleasure of going back to Porthkerry today to photograph Southbya (without disturbing it) with my new portable 'DinoLite' USB microscope. With laptop packed we set off, and arriving at Porthkerry we were greeted by a large flood, over topping of the Nant Talwg and the Whitelands Brook into the low lying area of the golf course.  Once we had navigated the flood waters we made it to the beach. The heavy rain from the last few days had manifested itself into mini water falls on the cliff. There was evidence of fresh cliff fall. The section with Southbya was relatively dry and in contrast to the section of cliff next to it which was pouring with water (and has no Southbya) suggests it likes it damp but not too wet. I've used the DinoLite in the office and it works well with dry things, it has internal LED lighting which is useful. However water on the damp cliff created a big reflection, and even when I turned the lights off it wasn't great. It was also a two person job, one holding the microscope and the other the laptop. I also had to tweek the images afterwards. So my conclusion is that its not great for photographing anything where water is involved and even after this attempt they are not as good as Barry's images...maybe ill write to Santa and ask for a good camera.
flooded mini golf course at Porthkerry (view towards the sea)
Laptop and digital microscope (with Southbya location in background) 



In other 'moss news' myself and Jon Graham start a small project for Natural England looking at Tufa springs in Gloucestershire, so feel free to chip in if you know any great sites. We have also started to prepare a paper based on our two winters of fieldwork looking at the chemical micro-habitats of Scorpidum in Wales.  That should keep me out of trouble. 



Saturday, 14 March 2015

coastal tufa liverworts

A few more trips on the Glamorgan Coast over the last few weeks. Highlights include accidentally finding the most easterly record of the Maidenhair Fern Adiantum capillus-veneris associated with Pellia endiviifolia and Eucladium verticallatum on a small patch of tufa in a small crevasse in Penarth cliff (most easterly record) and only confirmed record in the ST17 square (ST1865769887). It was also at this location that gravity supplied me with a nice block of tufa, which I duly sliced in half – noting it was entirely formed from numerous layers of Pellia…I wonder how long this takes to form and could it be geochemically dated ?

Pellia endiviifolia forming its own lump of tufa 
Thus far the majority of the coastal tufa cliff face liverworts appear to be Pellia sp however Julian Woodman (NRW) took me to see the elusive Southbya tophacea at the Aberthaw-Fontygary cliff section. It took a bit of squinting but once located we could just about get close enough to it for a look with our faces pressed up against the dripping rock face.  It occurred over a 10-20 m section, not continuously but in small patches, the cliff face protected by scrub and other plants, providing shade and protection from sea spray and winds. In places it looked like it was being ‘overcome’ by other more vigorous mosses but that may just be my novice eye.
Julian Woodman up close and personal with Southbya and a lot of Maidenhair Fern
blink and you'll miss it:  Southbya tophacea in amongst bases of the Maidenhair Fern - perhaps it will be associated with the fern elsewhere across the coast??
After a spot of lunch in the Fox and Hounds we popped over to Southerndown to the Cwm Mawr stream (SS8936572263), that’s the one that forms the waterfall that cascades onto the beach below. The stream section up on the cliff is quite spectacular tufa forming stream jam packed with mosses and liverworts in amongst a thick matt of yellow iris over a 100m or so stretch.


Cwm Mawr (SS 89365 72263) view to east - at least 100m of tufa forming stream packed with goodies in between yellow iris matt. Worth a visit Barry ?
The most common liverwort at Cwm Mawr was a thallose liverwort with thallus >1cm, lacking obvious midrib (to me anyhow),  gammae in obvious receptacles, upper surface of thallus covered in air pores in the centre of polygonal markings,  the capsules are distinctive ‘mushroom shape’ and I cant seem to find this in ‘the book’ or get close using the key. Can anyone help ? Im guessing its a common species.
Cwm Mawr SS 89365 72263 tufa forming stream above the cliff. I'm stuck on the ID for this thallose liverwort can anyone help, its distinctive 'mushroom' shaped capsule should be a give away ?