1.1
Monitoring of the relocated
seagrass bed (Halophila beccarii) for
survival and growth at Pak Nai was required to be conducted quarterly during
the construction phase of the Project as specified in Section 6.2.3
of the EM&A Manual.
1.2
Equipment used for monitoring
included a 50x50cm quadrat, measuring ruler,
digital camera and handheld GPS.
1.3
Monitoring was conducted at the
4 locations (A, B, C and D) on the intertidal flats at Pak Nai as
shown in Figure 1.1.
1.4
Sediment plugs on the
intertidal flats at Pak Nai were relocated using visual markers that had been
placed at each location at the time of transplantation,
and using GPS. Care was taken not to
disturb each site by avoiding trampling.
1.5
At each location (dimensions of
1.5 x 1.5m), monitoring was conducted by our ecologist to
measure presence/absence of seagrasses and seagrass cover. Monitoring also included observations on seed
germination, leaf size and general
condition of any seagrass present.
1.6
The ninth quarterly survey to
monitor the seagrass transplantation sites (A,
B, C and D) was conducted on 20th
January 2006 following relocation of sediment plugs in September 2003. A photographic record of each transplantation
site is presented in Figure 1.2.
1.7
During the monitoring visit, seagrass were found to occur at two
transplantation sites - Sites A and C.
Site A
1.8
Seagrasses were found at Site A
in previous surveys but were considered to have spread into the transplantation
site from the adjacent existing seagrass bed. The extent of seagrass coverage both within the
transplantation site and in adjacent areas was found to have increased when
compared to the findings of previous monitoring. Coverage within the transplantation area estimated
at 30%.
Site C
1.9
During the December 2004 survey
a small number of about half a dozen seagrass leaves were found at the edge of
the transplantation site in one of the corners.
During the September 2005 survey,
seagrass growth both within and adjacent to the transplantation site was found
to be very dense, with coverage
within the site estimated at 70%. During
the January 2006 surveys, coverage
had substantially decreased to approximately 10% of the transplantation site. It was considered that this seagrass has spread
into the transplantation site from seagrasses growing immediately adjacent to
the transplantation site.
Sites B and D
1.10
At transplantation sites B and
D, close observation of the mud
surface did not detect the presence of any seagrasses. At sites B and D,
no seagrass plants were present growing on the sediment previously identified
as supporting seagrass in the EIA report. Although the transplanted sediment may contain
seeds derived from previously existing seagrasses growing on the sediment, monitoring observations revealed no evidence of
germination since the previous monitoring survey.
1.11
Monitoring of relocated
sediment plugs was conducted at 4 locations on the Pak Nai intertidal flats on 20th
January 2006. Seagrasses were observed at two locations (Sites A and C). At both locations,
it was considered these seagrass shoots have spread to inside the
transplantation site from adjacent existing seagrass beds and were not derived
from germination of seeds contained in the transplanted sediment plugs. At the two other locations (Sites B and D)
monitoring observations indicated that there was no evidence of seed
germination despite the possibility that the relocated sediment may contain
seeds deposited by seagrasses living on it that had since disappeared.