A review of ethnobotanical studies reveals over 500 medicinal plants in Mindanao,Philippines

Medicinal plants have long been used to treat various diseases in both indigenous and non-indigenous populations of Mindanao,Philippines.Here,we extracted data from ethnobotanical studies to compile a comprehensive list of these medicinal plants and identify how and for what purpose they are most commonly used.We identified 530 verified medicinal plant species across 372 genera in 118 families.The two most frequently cited species were Euphorbia hirta and Psidium guajava.The most represented family was Fabaceae and the most represented genus was Ficus.A total of 28 medicinal plant species are designated as threatened at the national or global level;of these,11 are endemic to the Philippines.Medicinal plant preparations most commonly use leaves for oral administration to treat various diseases such as digestive issues,including diarrhea.This study underscores the need for further ethnobotanical investigations,particularly in areas lacking records.It also emphasizes the need for conservation of threatened and endemic medicinal plants to ensure sustainable utilization of this valuable resource.

Variation of the North Equatorial Current, Mindanao Current, and Kuroshio Current in a High-Resolution Data Assimilation during 2008–2012

Outputs from a high-resolution data assimilation system,the global Hybrid Coordinate Ocean Model and Navy Coupled Ocean Data Assimilation （HYCOM＋NCODA） 1/12° analysis,were analyzed for the period September 2008 to February 2012.The objectives were to evaluate the performance of the system in simulating ocean circulation in the tropical northwestern Pacific and to examine the seasonal to interannual variations of the western boundary currents.The HYCOM assimilation compares well with altimetry observations and mooring current measurements.The mean structures and standard deviations of velocities of the North Equatorial Current （NEC）,Mindanao Current （MC） and Kuroshio Current （KC） also compare well with previous observations.Seasonal to interannual variations of the NEC transport volume are closely correlated with the MC transport volume,instead of that of the KC.The NEC and MC transport volumes mainly show well-defined annual cycles,with their maxima in spring and minima in fall,and are closely related to the circulation changes in the Mindanao Dome （MD） region.In seasons of transport maxima,the MD region experiences negative SSH anomalies and a cyclonic gyre anomaly,and in seasons of transport minima the situation is reversed.The sea surface NEC bifurcation latitude （NBL） in the HYCOM assimilation also agrees well with altimetry observations.In 2009,the NBL shows an annual cycle similar to previous studies,reaching its southernmost position in summer and its northernmost position in winter.In 2010 and 2011,the NBL variations are dominantly influenced by La Ni（n）a events.The dynamics responsible for the seasonal to interannual variations of the NEC-MC-KC current system are also discussed.

Species Account of Anura ns from the Western Slope of Mt. Kita nglad, Mindanao Island, Philippines

The Mt. Kitanglad Range is one of the country’s important key biodiversity sites;however, information about anuran diversity in this protected area remains depauperate. Herein we provided accounts of anuran species from high-elevation forests, in three sites of the western slope of Mt. Kitanglad range. The combined belt-transect sampling and microha bitat searches accounted for 13 species representing five families. The most represented family was Rhacophoridae with five representative species of the genus Philautus. Twelve out of the 13 species documented in the current survey are endemic. Four previously unaccounted species(Pelophr yne brevipes, Pulchrana grandocula, Sanguirana mearnsi, and Philautus surrufus) were added and brought the total anurans known from Mt. Kitanglad to 26 species. Most of the species were also recorded in forested sites, suggestive of their lesser affinity to non-forested ecosystems. The additional species detected during our survey may also imply that full understanding of anuran diversity of Mt. Kitanglad remains far from complete.

Interannual variability in the Mindanao Eddy and its impact on thermohaline structure pattern

The major feature, interannual variability and variation cause of the Mindanao Eddy and its im- pact on the thermohaline structure are analyzed based on the Argo profiling float data, the history observed data and the SODA data. The analysis results show that the Mindanao Eddy is a per- manent cyclonic meso-scale eddy and spreads vertically from about 500 m depth upward do about 50 m depth. In addition to its strong seasonal variability, the Mindanao Eddy displays a remark- able interannual variability associated with ENSO. It strengthens and expands eastward during E1 Nifio while it weakens and retreats westward during La Nifia. The interannual variability in the Mindanao Eddy may be caused by the North Equatorial Counter Current, the North Equatorial Current, the Mindanao Current and the Indonesian Through Flow. The eddy variability can have a great influence on the thermohaline structure pattern in the local upper ocean. When the eddy is strong, the cold and low salinity water inside the eddy moves violently upward from deep layer, the thermoeline depth greatly shoals, and the subsurface high salinity water largely decreases ,with the upper mixed layer becoming thinner, and vice versa.

Climatology and seasonal variability of the Mindanao Undercurrent based on OFES data

The simulation of an ocean general circulation model for the earth simulator （OFES） is transformed to an isopycnal coordinate to investigate the spatial structure and seasonal variability of the Mindanao Under- current （MUC）. The results show that （1） potential density surfaces, δ0=26.5 and δ0=27.5, can be chosen to encompass the M UC layer. Southern Pacilic tropical water （SPTW）, Antarctic Intermediate Water （AAIW） and high potential density water （HPDW） constitute the MUC. （2） Climatologically, the MOC exists in the form of dual-core. In some months, the dual-core structure changes to a single-core structure. （3） Choosing section at 8°N for calculating the transport of the MUC transport is reliable. Potential density constraint provides a good method for calculating the transport of the MOC. （4） The annual mean transport of the MUC is 8.34 × 106 m3/s and varies considerably with seasons： stronger in late spring and weaker in winter.

Sea surface height variations in the Mindanao Dome region in response to the northern tropical Pacific winds

Sea surface height (SSH) variability in the Mindanao Dome (MD) region is found to be one of the strong variations in the northern Pacific. It is only weaker than that in the Kuroshio Extension area, and is comparable to that in the North Pacific Subtropical Countercurrent region. Based on a 1.5-layer reduced gravity model, we analyzed SSH variations in this region and their responses to northern tropical Pacific winds. The average SSH anomaly in the region varies mainly on a seasonal scale, with significant periods of 0.5 and 1 year, ENSO time scale2-7years, and time scale in excess of 8 years. Annual and long-term variabilities are comparably stronger. These variations are essentially a response to the northern tropical Pacific winds. On seasonal and ENSO time scales, they are mainly caused by wind anomalies east of the region, which generate westward-propagating, long Rossby waves. On time scales longer than 8 years, they are mostly induced by local Ekman pumping. Long-term SSH variations in the MD region and their responses to local winds are examined and discussed for the first time .

Variations of the Eco-Hydro-Climatic Environment Response to the 2015/2016 Super El Niño Event in the Mindanao Dome Upwelling System

A super El Niño event occurred in the equatorial Pacific during 2015-2016,accompanied by considerable regional eco-hydro-climatic variations within the Mindanao Dome(MD)upwelling system in the tropical western Pacific.Using timeseries of various oceanic data from 2013 to 2017,the variability of eco-hydro-climatic conditions response to the 2015/2016 super El Niño in the upper 300 m of the MD region are analyzed in this paper.Results showed that during the 2015/2016 super El Niño event,the upwelling in the MD region was greatly enhanced compared to those before and after this El Niño event.Upwelling Rossby waves and the massive loss of surface water in the western Pacific were suggested to be the main reasons for this enhanced upwelling.De-creased precipitation caused by changes in large-scale air-sea interaction led to the increased surface salinities.Changes in the struc-tures of the thermohaline and nutrient distribution in deep waters contributed to the increased surface chlorophyll a,suggesting a po-sitive effect of El Niño on surface carbon storage in the MD region.Based on the above analysis,the synopsis mechanism illustrating the eco-hydro-climatic changing processes over the MD upwelling system responding to the El Niño event was proposed.It high-lights the prospect for the role played by El Niño in local eco-hydro-climatic effects,which has further profound implications for understanding the influence of the global climate changes on the ocean carbon cycle.

NUMERICAL SIMULATION OF THE MINDANAO EDDY AND TROPICAL CURRENTS OF PACIFIC OCEAN

Results of numerical simulation of currents in the western North Tropical Pacific Ocean by using a barotropic primitive equation model with fine horizontal resolution agreed well with observations and showed that the Mindanao Cyclonic Eddy located north of the equator and east of Mindanao Island exists during most of the year with monthly (and large seasonal) variations in scope . strength and central location . In June , an anticyclonic eddy occurs northeast of Halmahera Island, strengthens to maximum in August , exists until October and then disappears . The observed large-scale circulation systems such as the North Equatorial Current . the Mindanao Current and the North Equatorial Countercurrent are all very well reproduced in the simulations.

Subthermocline anticyclonic gyre east of Mindanao and its relationship with the Mindanao Undercurrent

The quasi-permanent anticyclonic gyre （ACG） east of Mindanao is a dominant feature of the subthermocline circulation in the southem Philippine Sea, and it is believed closely associated with the continuous northward alongshore flow of the Mindanao Undercurrent （MUC）. In this study, the structure and variability of this ACG were investigated using the 1950-2012 output of the Oceanic General Circulation Model for the Earth Simulator （OFES）, which can reproduce well the structure of the climatological intermediate-layer circulation and satellite-observed sea level variations in the southern Philippine Sea. Between 26.8-27.3 ao, the ACG covers a large area from the Mindanao coast to 131 ~E and from 3~N to 10~N. Its anticyclonic flow structure is unrelated to the surface Halmahera Eddy. The eddy-resolving simulation of the OFES revealed that the ACG consists of two components. The southern ACG （SACG） is centered at -6~N, while the northern ACG （NACG） is centered at -10~N. Seasonal and interannual variations of the ACG are linked to the variations of the northward MUC transport along the Mindanao coast, and the role of the SACG is more important than the NACG. Stronger （weaker） ACGs lead to greater （smaller） MUC transport. On the interannual timescale, the SACG shows a spectrum peak at 4-8 years, while the NACG has enhanced power within the 3-5-year band. A lead-lag correlation analysis indicates that interannual variations of the ACGs and the MUC transport are partly associated with the E1 Nifio-Southern Oscillation. Possible causes for the ACG variability are discussed.

The identifi ed 30–50-day variation in the subthermocline current east of Mindanao

Based on nearly 4 year-long moored velocity measurements at 8°N/127°E and a high-resolution ocean model output,a signifi cant 30–50-day variation in the subthermocline current east of Mindanao was identifi ed for the fi rst time in addition to the 60–80-day variation reported in previous studies.The 30–50-day variation is an important component and it explains considerable variance same as that of the 60–80-day variation.The 30–50-day variation is vertically coherent in the subthermocline current.The standard deviations of the 30–50-day variation in zonal and meridional directions are of comparable,and is about 4.5–5 cm/s.Eddy-tracking analysis indicated that ocean eddies originating from the North Equatorial Current(10°N–11°N)contribute to the 30–50-day and the 60–80-day variations.The 30–50-day eddies propagate faster than the 60–80-day eddies.

DYNAMIC AND THERMOHALINE PROPERTIES OF THE MINDANAO UNDERCURRENT Ⅰ. DYNAMIC STRUCTURE

Hydrographic data from eleven 1986-1991 cruises at zonal sections near 8°N from the Philippine coast to 130°E were used to examine the dynamic structure of the western boundary currents there in the present study focusing on the Mindanao Undercurrent (MUC).The MUC with maximum velocity >10 cm/ was found to be a feature of both the individual cruises and multiyear mean velocity field as a countercurrent below the Mindanao Current (MC). Usually, the MUC occupies depths below 200 dbar and consists of more than one core.Its vertical and horizontal scales are 500 - 1000 m and 100-250 km, respectively , and vary greatly and irregularly . The spatial distribution of the MUC agreed with that of the westward deepening isopycnals in and below the thermocline . In the individual cruises , the volume transports of the MUC relative to 1500 dbar varied from 6.2 to 28.4×106m3 (average of 14.4× 10 6m3/s) while those relative to 3000 dbar varied from 15.4 to 43.9 ×106 m3/s (average of 25.4 ×106 m3/s ). The multiyear mean MUC transport was 5.9×106 m3/s relative to 1500 dbar and 8.7 × 106m3/s relative t0 3000 dbar . The difference between the multiyear mean MUC transport and that of individual cruises resulted from the MUC spatial variation .

DYNAMIC AND THERMOHALINE PROPERTIES OF THE MINDANAO UNDERCURRENT,PART Ⅱ: THERMOHALINE STRUCTURE

Hydrographic data from eleven 1986 - 1991 cruises at zonal sections near 8°N from the Philippine coast to 130°E were used to examine thermohaline smictim and waer mass properties of the western boundary cnrrents there, especially those of the Mindanao Underconnt (MUC). The finding that the MLC consisted of two water masses with salinity of M.6 at 26.9 σt and 34.52 at 27. 2 σt which were remnants of the lower part of the southern Pacific Subtropical Waer (SPSW) and of the Antarctic Intermediate Water (AAIW) of South Pacific origin, respectively, showed that the MUC was not a local transient but originaed elsewhere. As the MUC flowed from 7 .5°N to 8°N, part of it carrying the SPSW turns anticyclonically and eastward. The Northem Pacilic Intermediate Watr (NPIW) often joins the MUC, which suggests that the NPIW carried by the MC partly to northward as a result of the shear between the MC and the MUC or other proceesses. The shear instability provides the energy for the irregular fluctuation of the MUC.

The relation between the Mindanao Current and Mindanao Undercurrent on seasonal scale

The ocean general circulation model for the earth simulator（OFES） products is applied to estimate the transports of the Mindanao Current（MC） and the Mindanao undercurrent（MUC） and explore the relation between them on seasonal scale. In general, the MUC is composed of the lower part of the Southern Pacific Tropical Water（SPTW）and Antarctic Intermediate Water（AAIW）. While the deep northward core below 1 500 m is regarded as a portion of MUC. Both salinity and potential density restrictions become more reasonable to estimate the transports of MC/MUC as the properties of water mass having been taken into consideration. The climatological annual mean transport of MC is（37.4±5.81）×10~6 m^3/s while that of MUC is（23.92±6.47）×10~6 m^3/s integrated between 26.5 σ_θ and 27.7 σ_θ, and（17.53±5.45）×10~6 m^3/s integrated between 26.5 σ_θ and 27.5 σ_θ in the OFES. The variations of MC and MUC have good positive correlation with each other on the seasonal scale： The MC is stronger in spring and weaker in fall, which corresponds well with the MUC, and the correlation coefficient of them is 0.67 in the OFES.The same variations are also appeared in hybrid coordinate ocean model（HYCOM） results. Two sensitive experiments based on HYCOM are conducted to explore the relation between MC and MUC. The MUC（26.5〈σ_θ〈27.7） is strengthening as the MC increases with the enhancement of zonal wind field. It is shown,however, that the main part of the increasement is the deeper northward high potential density water（HPDW）,while the AAIW almost remains stable, SPTW decreases, and vice versa.

Meso-scale circulation at the intermediate-depth east of Mindanao observed by Argo profiling floats

The meso-scale circulation at the intermediate depth east of Mindanao is studied using Argo profiling floats observations. The trajectories and the parking-depth velocities of Argo floats show that the intermediate-depth circulation east of Mindanao contains significant meso-scale features that are highly variable both in space and in time. Both cyclonic and anticyclonic eddies at the intermediate depth (1000–2000 m) are indicated by the trajectories east of Mindanao. The mean tangential velocities of these eddies are about 10 cm/s at 2000 m and over 20 cm/s at 1000 m, which indicates that the geostrophic calculation may contain large errors due to the vigorous eddy activity at the reference levels. The analyses also suggest that these eddies might play an important role in mass and vorticity balances of the intermediate-depth circulation east of Mindanao.

2023年12月2日菲律宾棉兰老岛附近海域7.6级地震的快速产出参数

北京时间2023年12月2日22时37分在菲律宾棉兰老岛(Mindanao)东部海域发生7.6级地震。中国地震局地球物理研究所在震后启动快速响应,组织相关领域研究人员对此次地震的震源参数、震源机制、破裂过程和地震辐射能量等进行了估计,基于震源模型进行了震动图模拟、同震形变场模拟。结果表明,此次地震发生在菲律宾海板块与欧亚板块/巽他地块碰撞的俯冲带板片上,以逆冲机制为主,能量集中在前约40 s内释放,断层破裂最大滑动量达到7 m;震源辐射地震能量的效率偏低,慢度系数略低于全球平均水平,与同样矩震级大小的地震相比,震感不强烈;极震区震动烈度可能达Ⅸ度以上,可能的受灾范围近27000 km^(2);此次地震引起了显著的同震位移,最大水平向位移达到0.6 m、垂直向位移达到1.2 m。综合分析可知,此次地震不会产生大规模海啸。

棉兰老岛以东反气旋涡的Argo观测研究

报道了2003年1月至10月期间,由布放于西北太平洋中的Argo剖面浮标捕获的位于棉兰老岛以东海域的反气旋涡。该涡中心位于8.7°N、127.6°E附近,距大陆坡不远,沿等深线走向呈椭圆形分布。其长轴(NW-SE)约200km,短轴(NE-SW)长约120km。Argo浮标的漂移轨迹及其在表层及1 500db层的漂移速度场表明,该反气旋涡位于温跃层以下,中层海洋特征。在1 500db层上,涡的外围平均切向速度为11.9—14.0cm.s-1,旋转周期约为40d。温、盐度断面分布表明,该反气旋涡内的温盐结构非常复杂,可能与源自南、北半球的中层水团在涡旋内交汇并发生变性有关。

北太平洋西边界流的低频变化特征

基于日本气象厅长时间序列的温、盐度再分析资料,利用动力计算方法分析了北太平洋西边界的北赤道流及其下游黑潮和棉兰老流流量的年际和年代际变化,并探讨了北赤道流变化的可能原因。结果表明,北赤道流和黑潮具有比较一致的年际和年代际变化,均在1976年前后发生了一次气候跃变,之后有长期偏强的趋势,而棉兰老流的年际和年代际变化则有所不同。特别是,北赤道流1976年之后增加的流量似乎大多进入黑潮,而流入棉兰老流的流量则减少。进一步的分析还表明,西传的Rossby波和棉兰老冷涡的变动可能对北赤道流的年际变化有重要影响。

ENSO循环相联系的北太平洋低纬度异常西边界流

用SODA海洋同化和NCEP大气再分析资料,分析了热带太平洋次表层海温异常主要模态与北太平洋低纬度西边界流海域上层海洋环流和亚洲-北太平洋地区大气垂直和水平流场变化之间的关系,得到以下结果:(1)在热带太平洋海洋次表层ENSO事件具有两种模态,二者组合构成ENSO循环。第一模态为ENSO成熟期,主要出现在冬季,第二模态为ENSO过渡期,主要出现夏季。(2)ENSO循环对北太平洋低纬度西边界流区上层海洋环流有重要影响。在El Nio发展期或La Nia衰退期,该区出现气旋性异常环流,北赤道流(NEC)加强,NEC分叉位置北移,棉兰老海流(MC)加大,菲律宾以东黑潮(KC)减小,北赤道逆流(NECC)最强。在El Nio(La Nia)成熟期,该区气旋性(反气旋性)异常环流达最强,NEC最强(最弱),NEC分叉位置最北(最南),MC最大(最小),KC最小(最大),NECC减弱(加强)。在El Nio衰退期或La Nia发展期与El Nio发展期相反,该区出现反气旋性异常环流,由此导致相应流系异常发生反位相变化。(3)ENSO循环对北太平洋低纬度西边界流海域上层海洋环流的影响是通过ENSO事件期间热带太平洋热力状况异常改变上空大气环流来实现的。ENSO事件首先造成热带太平洋海洋热力状况异常,导致其上空对流活动异常,后者直接或间接通过"大气桥"能量传输引起相关地区大气环流场的变化,致使海面风应力场异常,进而强迫上层海洋环流场的相应变化。文章最后还分析了ENSO事件期间菲律宾附近异常反气旋或异常气旋性风场的产生和持续原因,讨论了北太平洋低纬度西边界流海域海气相互作用在ENSO循环中的贡献。

热带西太平洋主要流系的季节变化和年际变化

利用美国国家环境预报中心的太平洋海域 1 980— 1 995年四维同化资料 ,计算了棉兰老海流和与之有密切联系的北赤道流、北赤道逆流流量的年际变化和季节变化特征。由此得出以下结论 :( 1 )棉兰老海流对北赤道逆流的初始流量贡献较大 ,是北赤道逆流的主要水源提供者之一 ,棉兰老海流与黑潮在季节变化中存在反相关系 ;( 2 )棉兰老海流在厄尔尼诺年初期加强 ,在反厄尔尼诺期间减弱 ;( 3)棉兰老海流的季节变化信号强于年际变化信号。

Low-frequency variability of the North Equatorial Current bifurcation in the past 40 years from SODA

The low-frequency variability of the North Equatorial Current （NEC） bifurcation during 1958 to 2001 was investigated with the Simple Ocean Data Assimilation （SODA） 2.0.2 dataset. In agreement with recent observations, the NEC bifurcation latitude （NBL） shifted northward as depth increases, from about 12.7°N near the surface to about 17.1°N at depths around 500 m for the annual average. This study reveals that the interannual variations of NBL, with five years period, mainly focused on the upper 500 m with amplitude increasing as depth increased. The NBL shifted southward in the past 40 years, which was more significant in the subsurface at more than -0.02°/a. The NBL manifests itself in the transports of NMK （NEC-Mindanao Current （MC）-Kuroshio） system in strong relationship with MC （0.7） and Kuroshio （-0.7）. The EOF analysis of meridional velocity off the Philippine coast shows that the first mode, explaining 62% of variance and 5 years period, was highly correlated with the southward shift of NBL with coefficient at about 0.75. The southward shift of NBL consists with the weakening of MC and strengthening of Kuroshio, which exhibited linear trends at -0.24Sv/a and 0.11Sv/a. Both interannual variation and trend of NBL were closely related to the variation of NMK system.