Southeast Asia: An assessment

Dr Anukul Buranapratheprat A , Phan Minh Thu B and Joseph Palermo C

A Department of AquaƟ c Science, Burapha University, Thailand Wikipage: hƩ p://www.nf-pogo-alumni.org/~Anukul+Buranapratheprat B Department of Marine Environment and Ecology, InsƟ tute of Oceanography, Vietnam Wikipage: hƩ p://www.nf-pogo-alumni.org/~Phan+Minh+Thu C Marine Science InsƟ tute, University of the Philippines Wikipage: hƩ p://www.nf-pogo-alumni.org/~Joseph+Palermo

Dr Buranapratheprat Mr Thu Mr Palermo

Following the fi rst set of fi eld trips conducted by each of the parƟ cipaƟ ng countries in this year’s NANO Southeast Asia project, a second set of fi eldtrips has been conducted to complete the fi eld sampling work. The previous issue of NANO News (issue 6) included a report on the acƟ viƟ es conducted earlier this year by NANO alumni and associates in Thailand, Vietnam and the Philippines. The second set of fi eldtrips corresponded with the wet season in Thailand, and the dry season in Vietnam. Tthe fi eldwork from the Philippines group led by Joseph Palermo had already been completed earlier this year and summarised in the last NANO news.

2nd fi eld observaƟ ons in Cam Ranh Bay and Nha Trang Bay, Vietnam: The survey was carried out on 13 – 14 May 2014 for Nha Trang staƟ ons and 17 – 18 May 2014 for Cam Ranh staƟ ons. Weather and sea condiƟ ons were good but there were some problems with the equipment, therefore this trip took more Ɵ me than the last one. For 11 staƟ ons at Nha Trang Bay, the fi eld campaign conƟ nued from 6 am to 6 pm for two days with 9 researchers (8 from InsƟ tute of Oceanography and 1 from Ho Chi Minh City InsƟ tute of Physics). Water sampling at river mouths and gates of wastewater discharges were collected the day aŌ er fi nishing the trip in Nha Trang bay. In Cam Ranh Bay, water sampling was carried out for 8 staƟ ons and 4 wastewater discharge staƟ ons by using a local fi shing boat from 5 am to 8 pm. This took longer than in the Nha Trang bay. Physical parameters were measured by using a CTD and a current meter. Water samples in the bays were collected at surface and boƩ om layers and stored at 4 o C in dark container for the analysis of nutrients, TSS and Chlorophyll-a in the laboratory. All samples were analysed within one week aŌ er the fi eld trips. Light profi les were also measured by using a PRR2600. In addiƟ on, other parameters including Fluorescent-chlorophyll-a profi les, marine opƟ cs and primary producƟ on under the VAST project (VAST-DLT.01/13-14) were also executed. Although manpower was limited and the equipment had some problems (the opƟ cal depth of PRR2600 was not operaƟ onal), the fi eld observaƟ on fi nished as expected.

Scenes of fi eld work in Vietnam

2nd fi eld observaƟ ons in the upper Gulf of Thailand: Field observaƟ ons at the river mouths and in the upper Gulf of Thailand (UGoT) were carried out on 31 July – 1 August 2014 and 8 - 9 August 2014, respecƟ vely, which corresponded to the wet season. The physical and chemical parameters including temperature, salinity, nitrate, nitrite, phosphate, ammonia, silicate, dissolved oxygen, pH, BOD and chlorophyll-a were measured. The sea condiƟ on was quite rough compared with the fi rst cruise due to strong southwest wind. Freshwater discharges from the rivers were of greater volume in this wet season. A plume of low salinity water from the Chaopraya River in the northern part of the study area was observed. Overall salinity in UGoT was sƟ ll not so low and no blooming of phytoplankton was observed. The analysis of chemical water qualiƟ es is sƟ ll going on. When this has been done, we expect to see the diff erences of environmental condiƟ ons between dry and wet seasons with regard to eutrophicaƟ on in UGoT.

Scenes of fi eld work in Thailand

Next Steps: Once all the samples have been analysed in the laboratory, the data from all three parƟ cipaƟ ng countries will be collated and applicaƟ on of suitable methods for determining water residence Ɵ me and the calculaƟ on of eutrophicaƟ on index will be carried out. Comparison between results in each country between samples collected in the wet and dry seasons will be made and subsequent assessments of water quality and levels of eutrophicaƟ on will be undertaken. A follow up meeƟ ng of the NANO SEA parƟ cipants is scheduled for later this year to complete the fi nal report, policy papers where appropriate and a scienƟfi c paper for publicaƟ on in a peer-reviewed journal.

Stella Betancur working on parella Betancur working on parƟ cle light abƟ cle light absorp rp Ɵ on coe Ɵ on coe ffi cient measurements for the ffi cient measurements for the LaƟ n America Regional Project. Read the Ɵ n America Regional Project. Read the latest updates on LA-NANO at page 14 est updates on LA-NANO at page 14