Wednesday, June 17, 2009

Advanced elective module (AEM): Water quality and pollution (8 - 15 Jun 09)

What an intense week! 6 consecutive days of conducting my AEM to W5 cluster of schools. Luckily, the AEM involves 3 field trips and 1 out-of-classroom lesson at the local pond. They certainly spice up the entire module. To make this post short and sweet, I will only include highlights of the module here.

Bug hunting. This time round, we gave SP Forest a miss as the whole area appeared to be under construction. Instead, we headed to a tributary of Sungei Pandan. This stream flows adjacent to AYE, next to International Business Park. Lots of snails, dragonfly nymphs, damselfly nymphs and fishes in the water. Even managed to scoop up a freshwater eel.

Back to my number one favourite haunt for water quality monitoring - Ngee Ann Stream. The place is fascinating for its variety of habitats which the stream passes - open country natural to secondary forest to open country urban. You even get to find riffles (so rare in our water bodies) in a part of the forest. As usual, we had our customary group photo at one of the more scenic spots.

Its educational value is also underscored by having 2 tributaries (1 from Clementi Road, another from Bukit Timah Road) joining up to hit Ulu Pandan Road. Based on the water quality data, the 2 tributaries have rather distinct personalities e.g. pH, turbidity, iron, alumuminium, conductivity. But of particular concern is the rather high pH (> 9) in the tributary from Bt Timah Rd. This was never observed in 2008 even though the values were consistent with the data collected in the previous week in a course for MOE (see earlier post). I will reserve my speculations till further data is available.

This time round, we tried a new field location - Sungei Pandan/ Pandan Mangroves. This is one of the rare mangrove swamps which is not found in the northern coast of Singapore. (Purists may argue that this is not a true mangrove as it does not possess all the defining vegetation and habitats but what the heck.)
Any scientific study in mangroves or coasts will have to check out the tides. We found ourselves in a rising tide but still at a relatively low level, meaning mud walking (or sinking) for all involved.
Found lots of Passiflora foetida growing wild and managed to sample some ripe fruits before the birds get to them.
This stretch of Sg Pandan is especially interesting as its flow is dammed by a set of sluice gates. The water quality data will immediately scream out the differences between the stretches before and after the gates, the most basic being one side having fresh water while the other side has salt water.

Some commonly seen activities of students: trying out the disposable glove in a way it is not designed for; drying out the feet when the shoes are wet

No comments: