Daily Mud - An Update

So what’s been happening on site, other than the fabulous Italian Job (Naucrates' visit, not Rossi)? The last two weeks have been largely digging and signing. As suggested earlier the focus has been on channel 2, which runs diagonally across the pond. In consultation with Jim from Mangrove Action Project the decision was made to try to deepen and widen this channel to aid drainage and produce more hills.
The tricky part is digging around the sluice gate – the lowest part of the site. Even at low water this is often part submerged, and water from the rest of the site slowly drains out via here, necessitating digging underwater. In itself, digging in knee-deep water is not a problem when widening the sides but it’s hard to judge the evenness of the deepening as the water is never clear. However digging is impossible if the water is too deep (below, where the water at Hill T would be chest deep), or if a lot of water is still draining out of the pond due to tide or rain (Thursday 23rd!). So when the opportunity arose, channel 2 near the gate was widened and deepened. If not, other parts of 2 and 2C were excavated. This included extending 2C further east another 6 meters and making 2C much more curved, by widening more on the opposite side to the nearest hill, which are placed on alternate sides of the channel being dug (below). All this digging has produced more hills. We are at ‘X’, almost out of letters. There’s been a lot of activity at home therefore to make enough signs to label the new hills, produce signs for hills have not been labelled to date and replace broken ones. White cardboard-like plastic has been used and permanent markers.

Hill C and I continue to thrive. To my surprise the two Test Planting plots (green signs) on the pond floor (also Rhizophora apiculata) also seem to be struggling along but surviving. Both have had a random sample of 15 plants tagged and these are being measured for height leaf numbers and condition. Bang Don and I both thought that these dibblings would die as the soil is saturated and sloppy.

Other Dibbling and Planting
As a test a Nypa palm wilding of approx 30cm has been transplanted from a poor site near the pond onto Hill X. This will be monitored in the usual way. Hill O has received one R. apiculata volunteer, but no buds yet. Test Planting Plot 3 (green sign) has been established with Bruguiera cylindrica and Ceriops tagal. Again a sample will be tagged next week and monitored for progress, to compare against Hill L and Hill E respectively. Hill F also received B. cylindrica dibbling and Hill Q R. apiculata. Hill N has received a Nypa seedling that has been grown in a mix of soil and clay in my own garden. 24cm tall its progress will be monitored but so far it looks happy in its new home.

Charts and Tides
One final minor triumph. The below is a schematic of the pond at cross-section. It shows the heights of the hills, pond, datum point and average channel depth. What observations onsite confirm is that our measurements correctly predict that at very lowest high tides (from Tide.com) only the channels are filled with water and there is no inundation of the pond floor itself. So the pond is just on the boundary between mudflat, in the Watson sense, and mangrove territory on the slope from dry land to the sea. So what will happen in the next couple of weeks? Channel 2 will be completed. On Friday I tried to dig out a big piece of mangrove trunk that ran across the channel, partially blocking it. At one end is Hill X. So by digging I tried to find the other end, but to no avail – the end remained buried in the mud. So the log will be sawn in two and removed that way. More species will be dibbled, as they come into season. Avicennia sp of all three species are now available, and there are two Xylocarpus granatum in my garden at about three feet that will be transplanted onto their own hills. Watch this mud.