Lab session:Follow up on “measuring Thalassia growth”

25 06 2007

Thanks to Ms Siti and her friends who helped us ‘collect’ seagrass with the holes poked through them, we were able to follow up on our tests to measure seagrass growth when we returned from our various overseas trips. 😀 So today, we gathered in the Biology lab to study the growth of the seagrass.

Unfortunately, we realised that some of the sheaths had dropped off and there were singular leaf blades (most likely separated in the process of transportation). We were rather at a loss as to how to measure, since if there were no sheaths, we couldn’t find the hole in the sheath to measure from to track the growth. Thank goodness Ms Siti was there and suggested an alternative – we would measure 2 cm from the bottom of the seagrass for uniformity. And thus we began.

We measured the distance between the holes (for most, the hole in the sheath was imagined to be present 2cm above the bottom of the seagrass) as the growth, and the length and width of each leaf blade in each thalassia plant and dutifully recorded everything down.

We were done after a few hours 🙂 and actually, it was mostly uneventful, aside from one very sleepy person who kept reading off the wrong dimensions on the ruler, one very high person who commented oddly that measurement was more effective with wet sticky seagrass (“Because the seagrass will Stick to the Ruler!!!”) and two other rather quiet people including Ms Siti. (:

Stay tuned for pictures and further posts!!

monitoring session on 17 June

17 06 2007

So after yesterday’s episode (all the lateness…) we all managed to reach Labrador Park on time. Or as much on time as possible, given the heavy, heavy downpour around central Singapore. We nearly hoped that today’s session would be cancelled, we weren’t trying to slack, but the rain was really very heavy. But Mr Lim dashed all our hopes by saying that if we didn’t do it today, it would be hard for us to find another day with as low a tide as today’s.
However, at 10 minutes past 7, the gate was still not open, so we had to climb over the railing and “crab walk” along the ledge to get to the ramp. We also packed our ponchos in preparation for an expedition tomorrow and thus, had to carry umbrellas. Which we couldn’t while climbing over the rail and thus, got thoroughly wet.
After we managed to get into the beach safely, we placed our bags under the bridge and prepared to get even more wet! As I was the one who was going to measure the seagrass, I had the honour of wearing a poncho of Ms Siti’s, while the rest had to carry around their umbrellas. However, i ended up even more wet than the rest…
As we had left our all-important file and clipboard locked up in school, Siling had to print out new copies of the data sheet. These data sheets were not waterproof, unlike the ones which were given to us. Thus, we were slightly worried that our data would get smudged. However, we tried to work as quickly as possible.
The tide was already rising when we started at 7.22 am, so we quickly improvised. Initially, Sihui and I would measure and do the quadrat-reading, with Siling being the sole recorder. However, Ms Siti realised it was too slow, and thus, we split up into two teams – with Ms Siti measuring and Sihui recording, and I measuring and Siling recording.
Siling and I quickly recorded, and saw some interesting things such as Soft Corals which have been uprooted and another species of Soft Corals. However, due to the rain, we didn’t manage to catch sight of any crabs. We managed to cover 33 quadrats between us and Ms Siti and Sihui, while Mr Lim took the GPS coordinate readings of around the Thalassia hemprichii patch and the Halophila ovalis patch. We managed to do everything by 8.04 am. By that time, the rain was already lessening. We quickly washed up and while Ms Siti and Mr Lim went off, the three of us waited for Sihui and Siling’s parents to pick us up and go for breakfast(:

We checked on our little patch of Thalassiawith-holes-in-the-sheath and it’s still safe and sound! Hopefully it would remain this way till Ms Siti goes to collect the samples 😀

measuring Thalassia growth

16 06 2007

Today, we went down to Labrador to begin the test to measure Thalassia growth. The plan was for each of us to be armed with a .22 hypodermic needle, to be used to poke a small but still visible hole in the sheaths of the seagrass in a designated patch. After a few days, we’d return to the same small patch and gather(aka dig out and collect) some of the seagrass from that patch. By measuring the distance between the hole in the sheath and the hole in the seagrass leaves, we would be able to track the average growth of the seagrass.
And so we began by choosing a patch of seagrass. The tide that day was very low and we quickly chose a small patch that was neither too overgrown nor too bare- just average. On the patch, we measured a square about the size of a quadrat and pegged tent pegs into the four corners. After tying raffia string to the tent pegs to mark out the square more clearly, we used a mallet to pound and embed the tent pegs into the ground.
Finally, we began the tedious job of poking the holes into the thalassia seagrass. It wasn’t as easy as expected- we had to dig into the sand to find the sheaths to poke into with the needles, and it was numbing to keep squatting. Thankfully, with our concerted efforts, we were satisfied and decided that we had poked holes in enough seagrass. Our target was 50 leaf sheaths in total so that even if some of the seagrass had died or been eaten or even mysteriously disappeared, we’d still have enough to do our calculations with.
Settled, we happily went home! Thank you Ms Siti for always coming to help out! And sorry if the explanations aren’t very clear, photos will be up soon for better understanding!

Because our entire team (including Mr Lim) would be leaving for an expedition in Hong Kong from the 18th to the 22nd, Ms Siti helped us collect the seagrass samples that we needed before they died. Thank you Ms Siti again! 😀
This plan was suggested by Dr Len McKenzie when he was in Singapore for the Seagrass Workshop. The sheath is where each leaf blade in the plant grows from, so when we poked a hole in the sheath, the hole would go through all the leaves of the thalassia, and this is what made our plan feasible.

up next…

14 06 2007

it’s been such a long time since we did any seagrass monitoring – nearly 2 months! hopefully we haven’t forgotten all we’ve learnt(: our next monitoring session’s coming up!
on the 16th of June, we will be conducting our experiment to find out how long a Thalassia leaf will grow to in a certain amount of time. on the 17th of June, we will also be going down to conduct our usual monitoring:D
so this is just a brief update on what we will be doing this weekend, look out for our next post on the monitoring session!

another blog!

14 06 2007

We have just found another blog about Labrador Park!
This blog is done by a group of local naturalists and they have really cool pictures! It focuses more on the natural habitat and less on seagrasses though. Nevertheless, it is very interesting, go take a look at it!