The Boao coastal system along the eastern coast of Hainan Island is a dynamic delta-tidal inlet-barrier formed during the late Holocene. The delta developed inside a shallow lagoon barred by a sandy barrier with a nar...The Boao coastal system along the eastern coast of Hainan Island is a dynamic delta-tidal inlet-barrier formed during the late Holocene. The delta developed inside a shallow lagoon barred by a sandy barrier with a narrow, shallow tidal inlet opening. Two major distributary channels separated by small islands characterize the delta. The lagoon is silting up receiving and trapping sediments from both the river and, in minor measure during storms, through the tidal inlet opening and barrier washovers. The barrier at the tidal inlet is highly dynamic and changes its form, accreting (migrating spit) against the inlet during fair-weather conditions and being eroded during storms and river floods. The delta has almost completely filled the lagoon and major concerns exist on the effect that ongoing large development plans may have on the environment. These concerns include the effect on floods and rate of siltation once banks of the islands have been stabilized and floodwater and sediment load are impeded from spreading over the lowlands, and the effect of increasing pollutant loads from the new facilities on the ecosystems of the increasingly restricting lagoon water and on the seashores.展开更多
We report that vector magnetograph (VMG) observations of the solar photosphere are being carride out by the Solar Flare Telescope (SOFT) at BOAO. The VMG uses a narrow band Lyot filter (FWHM=0 125A) for Stokes paramet...We report that vector magnetograph (VMG) observations of the solar photosphere are being carride out by the Solar Flare Telescope (SOFT) at BOAO. The VMG uses a narrow band Lyot filter (FWHM=0 125A) for Stokes parameter (I, Q, U, V) observations to obtain longitudinal and transverse fields. We have obtained a filter convolved line profile of Fe I 6302 5 for VMG by changing the central wavelength of the Lyot filter, which is consistent with the Sacremento Peak spectral atlas data. Using the line profile, we have determined calibration coefficients of longitudinal and transverse fields by the line slope method. Then we have compared vector fields of AR8422 observed at BOAO with those at Mitaka. The comparison shows that longitudinal fields are very similar to each other, but transverse fields are a little different. Finally, we present Hα and magnetic observations of AR8419 during its flaring activity (M3 1/1B).展开更多
Sedimentary successions and internal structure of the coastal barrier-lagoon system of Boao, eastern Hainan Island were studied through utilizing data from test holes and trenches and ground-penetrating-radar (GPR) pr...Sedimentary successions and internal structure of the coastal barrier-lagoon system of Boao, eastern Hainan Island were studied through utilizing data from test holes and trenches and ground-penetrating-radar (GPR) profiles. During late Pleistocene, fluvial and delta plains developed over an unevenly eroded bedrock during low sea level stand, followed by the formation of littoral and lagoon facies and defined coastal barrier-lagoon-estuary system during the post-glacial uppermost Pleistocene-lower Holocene eustatic rise of the sea level, and the upper Holocene high stand. GPR results show that Yudaitan, a sandy coastal bar backed by a low-laying land (shoal) just east of the active lagoon, is a continuous, parallel and slightly-wavy reflectors indicating homogeneous sandy or sandy gravel sediments, and inclined reflectors partly caused by progradation and accumulation of beach sand and gravel. Quasi-continuous, hummocky and chaotic reflectors from the shoal of Nangang village correspond to mixed accumulation of sands and clay. This research indicates the GPR is a non-intrusive, rapid, and economical method for high-resolution profiling of subsurface sediments in sandy gravelly coast.展开更多
THE world is currently experiencing unprecedented transformation. The process of economic globalization has undergone profound changes, the global multilateral mechanism is undergoing deep adjustments, and the existin...THE world is currently experiencing unprecedented transformation. The process of economic globalization has undergone profound changes, the global multilateral mechanism is undergoing deep adjustments, and the existing international system and the global order need to be profoundly transformed and remolded.展开更多
Boao,10 April 2018 Your Excellencies Heads of State and Government,Heads of International Organizations,Ministers,Incumbent and Incoming Members of the Board of Directors of the Boao Forum for Asia,Distinguished Guest...Boao,10 April 2018 Your Excellencies Heads of State and Government,Heads of International Organizations,Ministers,Incumbent and Incoming Members of the Board of Directors of the Boao Forum for Asia,Distinguished Guests,Ladies and Gentlemen,Friends.展开更多
文摘The Boao coastal system along the eastern coast of Hainan Island is a dynamic delta-tidal inlet-barrier formed during the late Holocene. The delta developed inside a shallow lagoon barred by a sandy barrier with a narrow, shallow tidal inlet opening. Two major distributary channels separated by small islands characterize the delta. The lagoon is silting up receiving and trapping sediments from both the river and, in minor measure during storms, through the tidal inlet opening and barrier washovers. The barrier at the tidal inlet is highly dynamic and changes its form, accreting (migrating spit) against the inlet during fair-weather conditions and being eroded during storms and river floods. The delta has almost completely filled the lagoon and major concerns exist on the effect that ongoing large development plans may have on the environment. These concerns include the effect on floods and rate of siltation once banks of the islands have been stabilized and floodwater and sediment load are impeded from spreading over the lowlands, and the effect of increasing pollutant loads from the new facilities on the ecosystems of the increasingly restricting lagoon water and on the seashores.
文摘We report that vector magnetograph (VMG) observations of the solar photosphere are being carride out by the Solar Flare Telescope (SOFT) at BOAO. The VMG uses a narrow band Lyot filter (FWHM=0 125A) for Stokes parameter (I, Q, U, V) observations to obtain longitudinal and transverse fields. We have obtained a filter convolved line profile of Fe I 6302 5 for VMG by changing the central wavelength of the Lyot filter, which is consistent with the Sacremento Peak spectral atlas data. Using the line profile, we have determined calibration coefficients of longitudinal and transverse fields by the line slope method. Then we have compared vector fields of AR8422 observed at BOAO with those at Mitaka. The comparison shows that longitudinal fields are very similar to each other, but transverse fields are a little different. Finally, we present Hα and magnetic observations of AR8419 during its flaring activity (M3 1/1B).
基金Project of cooperation between China and Canada, CIDA Project, No. CCHEP 282/19736
文摘Sedimentary successions and internal structure of the coastal barrier-lagoon system of Boao, eastern Hainan Island were studied through utilizing data from test holes and trenches and ground-penetrating-radar (GPR) profiles. During late Pleistocene, fluvial and delta plains developed over an unevenly eroded bedrock during low sea level stand, followed by the formation of littoral and lagoon facies and defined coastal barrier-lagoon-estuary system during the post-glacial uppermost Pleistocene-lower Holocene eustatic rise of the sea level, and the upper Holocene high stand. GPR results show that Yudaitan, a sandy coastal bar backed by a low-laying land (shoal) just east of the active lagoon, is a continuous, parallel and slightly-wavy reflectors indicating homogeneous sandy or sandy gravel sediments, and inclined reflectors partly caused by progradation and accumulation of beach sand and gravel. Quasi-continuous, hummocky and chaotic reflectors from the shoal of Nangang village correspond to mixed accumulation of sands and clay. This research indicates the GPR is a non-intrusive, rapid, and economical method for high-resolution profiling of subsurface sediments in sandy gravelly coast.
文摘THE world is currently experiencing unprecedented transformation. The process of economic globalization has undergone profound changes, the global multilateral mechanism is undergoing deep adjustments, and the existing international system and the global order need to be profoundly transformed and remolded.
文摘Boao,10 April 2018 Your Excellencies Heads of State and Government,Heads of International Organizations,Ministers,Incumbent and Incoming Members of the Board of Directors of the Boao Forum for Asia,Distinguished Guests,Ladies and Gentlemen,Friends.
