Saturday, September 14, 2013

Meanwhile in Maldives.....

So for the past week or so, I have been working on an Environmental Monitoring Project. Some random resort decided their beach is eroding too much and they got way too much seagrass for their comfort and decided to do a major coastal modification project. They dredged an area within the inner lagoon and dumped a lot of sand onto the eroding beach. Also, they dug out a lot of seagrass around the island. Now; our job is to determine if impacts, adverse or positive were within tolerable/acceptable levels after the project has been carried out.
As majority of the work was carried out close to the island, the easiest way to assess the damage from this project was to analyze corals around the project site; the housereef. We placed permanent 1m by 1m quadrates at study sites. The idea was to examine changes in live coral community; changes in species composition, cover by live corals...etc. It was within expected outcomes that some amount of coral will die out due to high turbidity from dredging activities. What we are more interested is the recovery rate.
Anyways, so what we were doing for the past 2 years... I haven't got a clue. I got the project very recently and decided to spice things up with more technical jargon and perhaps a little bit more real information to help determine recovery rate and such. So to utilize the permanent quadrate to its full potential, I started out with simple coral cover analysis.

Try One:
Before going there let me explain one of the tools we use: CPCe
Basically, you take photo of the quadrate (the reef with the quadrate if you will) and use that photo to calculate area of the seabed covered by corals, dead corals, sand..etc..
To actually measure/identify/mark borders and calculate actual areas will be quite difficult if not impossible for large numbers of quadrates. So you take the photo and use random sampling thingie (automated within the program code) to place 20 random points on the photo. Then you classify the points; what is under each point. So you basically get a decent estimate of cover percentages by category.
So what I first did was use this method once to calculate cover percentage for live corals, dead corals and classify live corals to genus level.
So my colleague wrote the entire report and I was left to review it. While reviewing I noticed the results from CPCe analysis were very inaccurate so I investigated the underlying course. I realized it was merely due to sampling bias and if I repeat the process for about 5 times I would have a more accurate result. I did it and re-wrote the report.

Try Two:
While redoing the report with more accurate data, I realize we have more data/information than the eye meets. So I began digging deeper into the abyss of information.... I found many inconsistencies... unexplained variations.... and many more. So I began to dig even deeper... to find explanations for them... and I found them... most of it anyways... but the report which should have been about 20 pages long and done in about 1 day has become 100 pages long and taken me a whole week... now i am thinking this is too much information and I need to cut it down.... aaaaaah.


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