Northern Coast Of Taiwan Research Articles

Conceptual Framework for Disaster Management in Coastal Cities Using Climate Change Resilience and Coping Ability

Global warming and environmental changes have resulted in more frequent and extreme weather events, as well as larger-scale disasters around the world. This study presents a disaster risk analysis in Taiwan coastal area using the Climate Disaster Resilience Index (CDRI) and examines the strategies adopted by the coastal residents of Taiwan, through a new concept of “copability” analysis. Based on the results, the majority of the coastal regions fall under the medium-to-low resilient category with the south-western and northern coast of Taiwan as the most high-risk regions posing a high risk to millions of people facing climatic disasters in the future. The coping mechanisms used by local residents are also influenced by the socioeconomic status of the decision-makers as well as the synchronization of disasters. Based on the findings, a 4R management package is developed in which the copability and resilience management strategy are squeezed into four main sectors of resource, reason, roadmap, and respond to work towards a more coordinated management and use of natural resources across sectors and scales. It is advised that all governmental, private, and community actors implement coherent climate risk management measures, accompanied by mitigation initiatives, in order to establish a sustainable level of climate resilience in cities.

Surface Current Variations and Oceanic Fronts in the Southern East China Sea: Drifter Experiments, Coastal Radar Applications, and Satellite Observations

AbstractOcean currents in the southern East China Sea (ECS) are complex and have long lacked systematic observational data. Observations from coastal radars in northern Taiwan, along with several drifters and satellite data, reveal a detailed ECS surface flow structure and thermal front. Drifter trajectories followed the seasonal flow field and were oscillatory and trapped due to strong tidal currents. Three drifters crossed the oceanic front off the northern coast of Taiwan following the tidal motion with a rapid change in the sea surface temperature by 2.5°C, which was recorded within a small distance of 500 m. A significant seasonal water mass exchange cycle occurred in the southern ECS. Starting in October, the Kuroshio Current intrudes onto the ECS shelf, causing the formation of a southwestward Northern Taiwan Coastal Current that mixes with the China Coastal Current to form a southward flow in the northern Taiwan Strait. Beginning in March, the ocean current off northwestern Taiwan shifts northward and then gradually flows eastward into the Kuroshio region. With satellite‐derived and model‐simulated surface currents contradicting each other over long periods of time, hourly coastal radar data have not only successfully explained the spatiotemporal variations in the sea surface temperature, salinity, and chlorophyll concentration observed by satellites but have also resolved the long‐standing disputes over the surface currents in the southern ECS.

Wooden material culture and long-term historical processes in Heping Dao (Keelung, Taiwan)

Despite being a perishable material, wood can nonetheless show in its full complexity the materiality of daily life activities, identity construction, economic exploitation, and adaptation in colonial processes. The study of two sets of wood samples in well-defined archaeological colonial contexts from the site of Heping Dao, on the northern coast of Taiwan, has unveiled otherwise unknown aspects of native exchange, adoption of indigenous practices, and differences and similarities between early European colonialism and Japanese imperialism in Asia-Pacific. Despite the constraints of taxonomic identification in subtropical (and tropical) areas, the use of different coniferous wood types has been recorded: Cupressaceae, cf. Chamaecyparis spp., cf. Cryptomeria japonica and cf. Cunninghamia spp. The paper highlights the close relationship between wooden objects and diachronic historical processes and stresses the complexity of their study in colonial contexts, with implications toward the prehistoric period.

Ensemble-based sensitivity analysis and predictability of an extreme rainfall event over northern Taiwan in the Mei-yu season: The 2 June 2017 case

In the present study, an ensemble-based sensitivity analysis (ESA) on the extreme-rainfall event along the northern coast of Taiwan on 2 June 2017 in the Mei-yu season is performed using the results from 45 forecast members with a grid size of 2.5–5 km. An quasi-stationary rainband associated with the front produced localized rainfall up to 635 mm in 12 h (0000–1200 LST 2 June), causing serious flooding and inundation near the northern tip of Taiwan. With a relatively large spread (i.e., standard deviation or σ), small ensemble mean (~130 mm), and low probability of heavy rainfall in northern Taiwan, the ensemble indicates a lower predictability there, compared to the topographic rainfall over the mountains. However, the ESA allows for identification of several contributing factors to heavy rainfall in northern Taiwan in a quantitative manner as given below.With their impact given in change of (areal-mean) 6-h rainfall amount per one σ increase, these factors include: (1) surface frontal position and moving speed (−16.00 mm per 5 km h−1), (2) position of 700-hPa wind-shift line (+12.59 mm per 0.4° latitude), (3) environmental moisture amount near the surface front (+11.73 mm per 0.92 g kg−1 in mixing ratio), (4) timing and location of frontal low-pressure disturbance (+11.03 mm per 1.38° longitude), and (5) frontal intensity (+9.58 mm per 3 K in equivalent potential temperature difference across 0.5°). While many of the factors identified are interconnected, they tend to increase the local rainfall through lengthening the duration and enhancing near-surface convergence along the northwestern coast of Taiwan over the area immediately upstream.

Marine Debris in Green Sea Turtles along the Northern Coast of Taiwan

Sea turtles ingesting marine debris is a major problem worldwide. This is the first study ever done on the marine debris ingested by sea turtles in Taiwan, 191 dead green sea turtles from 2012 to 2019, mainly in northern coasts. We identified seven debris types and 15 colors. Plastic rope, soft and hard plastics, foam plastic and unidentified material were the most common ingested debris. White, transparent and mixture were either the common or the most common ingested color. Juveniles consumed more type of debris than the other age classes. Debris was found remain in the digestive tract for several weeks or longer prior to be found or excretion.

Diurnal to Seasonal Variations in Ocean Chlorophyll and Ocean Currents in the North of Taiwan Observed by Geostationary Ocean Color Imager and Coastal Radar

The waters in the north of Taiwan are located at the southern end of the East China Sea (ECS), adjacent to the Taiwan Strait (TS), and the Kuroshio region. To understand the physical dynamic process of ocean currents and the temporal and spatial distribution of the ocean chlorophyll concentration in the north of Taiwan, hourly coastal ocean dynamics applications radar (CODAR) flow field data and geostationary ocean color imager (GOCI) data are analyzed here. According to data from December 2014 to May 2020, the water in the TS flows along the northern coast of Taiwan into the Kuroshio region with a velocity of 0.13 m/s in spring and summer through the ECS. In winter, the Kuroshio invades the ECS shelf, where the water flows into the TS through the ECS with a velocity of 0.08 m/s. The seasonal variation of ocean chlorophyll concentration along the northwestern coast of Taiwan is obvious, where the average chlorophyll concentration from November to January exceeds 2.0 mg/m3, and the lowest concentration in spring is 1.4 mg/m3. It is apparent that the tidal currents in the north of Taiwan flow eastward and westward during ebb and flood periods, respectively. Affected by the background currents, the flow velocity exhibits significant seasonal changes, namely, 0.43 m/s in summer and 0.27 m/s in winter during the ebb period and is 0.26 m/s in summer and 0.45 m/s in winter during the flood period. The chlorophyll concentration near the shore is also significantly affected by the tidal currents. Based on CODAR data, virtual drifter experiments, and GOCI data, this research provides novel and important knowledge of ocean current movement process in the north of Taiwan and indicates diurnal to seasonal variations in the ocean chlorophyll concentration, facilitating future research on the interaction between the TS, ECS, and Kuroshio.

A long-term monitoring dataset of fish assemblages in rocky tidepools on the northern coast of Taiwan

The assemblage of fish species in the rocky intertidal zone is highly affected by the destructive impact of human activities and has an extended impact on land-sea interactions. There are a few long-term research projects that have focused on rocky intertidal ecosystems, especially on the resident fish community. Here, we describe a long-term time series dataset of fish collected by counting the number of anesthetized fishes at sampling stations in rocky tidepools in the intertidal zones on the northern coast of Taiwan. The species assemblages were monitored seasonally at three stations from 1999 to 2018. In total, 144 samples containing 1,577 individuals belonging to 106 species were recorded in the surveys. The resulting data can be used as background information for conservation and resilience studies of the fish community in coastal areas and to establish reasonable conservation strategies. This study presents valuable data to ecologists and fisheries biologists interested in understanding the temporal patterns of species abundance, richness, and composition in relation to environmental factors, climate change, and anthropogenic pressures.

Time series dataset of fish assemblages near thermal discharges at nuclear power plants in northern Taiwan

Long-term time series datasets with consistent sampling methods are rather rare, especially the ones of non-target coastal fishes. Here we described a long-term time series dataset of fish collected by trammel net fish sampling and observed by an underwater diving visual census near the thermal discharges at two nuclear power plants on the northern coast of Taiwan. Both experimental and control stations of these two investigations were monitored four times per year in the surrounding seas at both plants from 2000 to 2017. The underwater visual census mainly monitored reef fish assemblages and trammel net samples monitored pelagic or demersal fishes above the muddy/sandy bottom. In total, 508 samples containing 203,863 individuals from 347 taxa were recorded in both investigations at both plants. These data can be used by ecologists and fishery biologists interested in the elucidation of the temporal patterns of species abundance and composition.

Bioaccumulation of trace metals in octocorals depends on age and tissue compartmentalization.

Trace metal dynamics have not been studied with respect to growth increments in octocorals. It is particularly unknown whether ontogenetic compartmentalization of trace metal accumulation is species-specific. We studied here for the first time the intracolonial distribution and concentrations of 18 trace metals in the octocorals Subergorgia suberosa, Echinogorgia complexa and E. reticulata that were retrieved from the northern coast of Taiwan. Levels of trace metals were considerably elevated in corals collected at these particular coral habitats as a result of diverse anthropogenic inputs. There was a significant difference in the concentration of metals among octocorals except for Sn. Both species of Echinogorgia contained significantly higher concentrations of Cu, Zn and Al than Subergorgia suberosa. We used for the first time exponential growth curves that describe an age-specific relationship of octocoral trace metal concentrations of Cu, Zn, Cd, Cr and Pb where the distance from the grip point was reflecting younger age as linear regressions. The larger colony (C7) had a lower accumulation rate constant than the smaller one (C6) for Cu, Zn, Cd, Cr and Pb, while other trace metals showed an opposite trend. The Cu concentration declined exponentially from the grip point, whereas the concentrations of Zn, Cd, Cr and Pb increased exponentially. In S. suberosa and E. reticulata, Zn occurred primarily in coenosarc tissues and Zn concentrations increased with distance from the grip point in both skeletal and coenosarc tissues. Metals which appeared at high concentrations (e.g. Ca, Zn and Fe) generally tended to accumulate in the outer coenosarc tissues, while metals with low concentrations (e.g. V) tended to accumulate in the soft tissues of the inner skeleton.

Distribution and quantity of microplastic on sandy beaches along the northern coast of Taiwan

Plastic pollution is now ubiquitous in the world's oceans, and studies have shown macroplastic and microplastic pollution of beaches in several East Asian countries. However, to our knowledge, no study of microplastic pollution has been conducted in Taiwan yet. Therefore, we collected sand samples from four beaches along the northern coast of Taiwan in 2015 and extracted microplastic particles using a saturated NaCl solution. Microplastic particles were identified using synchrotron-based FTIR spectroscopy. We recovered 4 to 532 particles from eight 0.0125m3 samples, with a total of 1097 particles weighing 0.771g. A negative trend between the size of the particles and their numbers was documented. We thus established that microplastic pollution was ubiquitous along Taiwan's northern coast. Future research should more comprehensively sample beaches around the entirety of Taiwan's coast, and special emphasis should be placed on identifying different sources and movements of microplastic.

Rainband feature tracking for wind speeds around typhoon eyes using multiple sensors

In this article, five typhoon cases observed by quasi-concurrent satellite-based synthetic aperture radar (SAR) and Moderate Resolution Imaging Spectroradiometer (MODIS) were studied with a feature-tracking technique. The rainband features around typhoon eyes were first delineated using wavelet analysis, and then the wind speeds were estimated by feature tracking using quasi-concurrent multi-sensor images. It was found that the feature tracking-estimated wind speeds are reasonable compared with the maximum wind speed reported by the Joint Typhoon Warning Center (JTWC), which accounts for the radial dependence of wind speed using the Rankine combined vortex approximation. In a specific case, with the aid of Doppler radar observations near the northern coast of Taiwan, wind speed estimation based on the multi-sensor also shows consistent results. This study demonstrates that the local wind distribution of cyclonic winds around typhoon eyes at different radial distances from the typhoon centres may be derived from rainband feature tracking using quasi-concurrent multi-sensor images. This technique may offer useful wind information for typhoon simulations and forecasting.

Diversity of yeasts associated with the sea surface microlayer and underlying water along the northern coast of Taiwan

Yeast communities inhabiting the sea surface microlayer (SSML) on the northern coast of Taiwan were examined using a cultivation method and compared with those inhabiting the underlying water (UW) at a 50-cm depth. Culturable yeasts were recovered from the SSML and UW samples collected in the morning during 4 field campaigns, and 420 strains were isolated. The 420 isolates were grouped into 43 species using a polyphasic molecular approach, including sequence analysis of the 26S rDNA D1/D2 domain and 5.8S-ITS region. From the SSML samples, 12 genera and 39 species, including 7 new species of Cryptococcus sp. (1), Candida spp. (4), and Rhodotorula spp. (2), were isolated. From the UW samples, 10 genera and 21 species, including one new species of Rhodotorula sp. (1), were isolated. Rhodotorula mucilaginosa was the most abundant species present in the yeast community in SSML (37.6%) and UW (21.6%) samples. Basidiomycetous yeasts (63.6%) and pigmented yeasts (64.5%) comprised the major yeast population. The yeast community in the SSML had a higher species number and abundance than the UW. Moreover, although the majority of yeast community species were from the SSML, individual species distribution in the SSML was unequal.

Occurrence of Anisakis Larvae in Commercial Fish along the Northern Coast of Taiwan

Occurrence of Anisakis Larvae in Commercial Fish along the Northern Coast of Taiwan

Unusual distribution of floating seaweeds in the East China Sea in the early spring of 2012.

Floating seaweeds play important ecological roles in offshore waters. Recently, large amounts of rafting seaweed have been observed in the East China Sea. In early spring, juveniles of commercially important fish such as yellowtail accompany these seaweed rafts. Because the spatial distributions of seaweed rafts in the spring are poorly understood, research cruises were undertaken to investigate them in 2010, 2011, and 2012. Floating seaweed samples collected from the East China Sea during the three surveys contained only Sargassum horneri. In 2010 and 2011, seaweed rafts were distributed only in the continental shelf and the Kuroshio Front because they had become trapped in the convergence zone of the Kuroshio Front. However, in 2012, seaweed was also distributed in the Kuroshio Current and its outer waters, and massive strandings of seaweed rafts were observed on the northern coast of Taiwan and on Tarama Island in the Ryukyu Archipelago. Environmental data (wind, currents, and sea surface height) were compared among the surveys of 2010, 2011, and 2012. Two factors are speculated to have caused the unusual distribution in 2012. First, a continuous strong north wind produced an Ekman drift current that transported seaweed southwestward to the continental shelf and eventually stranded seaweed rafts on the coast of Taiwan. Second, an anticyclonic eddy covering northeast Taiwan and the Kuroshio Current west of Taiwan generated a geostrophic current that crossed the Kuroshio Current and transported the rafts to the Kuroshio Current and its outer waters. Such unusual seaweed distributions may influence the distribution of fauna accompanying the rafts.

Identifying and characterizing Yarrowia keelungensis sp. nov., an oil-degrading yeast isolated from the sea surface microlayer

Ascomycetous yeast strain SM-22 was isolated from the sea-surface microlayer near the Keelung City off the northern coast of Taiwan. This strain showed a cell surface hydrophobicity higher than 90 %, moderate UV A/B resistance, and it degraded 68 % of the total petroleum hydrocarbon content of an artificial seawater medium containing 1 % (v v(-1)) diesel oil within 15 days at 25 °C. The closest phylogenetic relative of this strain is Candida oslonensis CBS 10146(T), but it differs from strain SM-22 by a 3.7 % divergence (including 18 nucleotide substitutions and 2 gaps) in the D1/D2 domain sequence of the large subunit rRNA gene. This difference clearly suggests that the strain SM-22 represents a distinct species. Strain SM-22 does not produce ascospores on common sporulation media and it can therefore be considered an anamorph of the genus Yarrowia. Thus, the name Yarrowia keelungensis sp. nov. (type strain SM-22(T) = BCRC 23110(T) = JCM 14894(T) = CBS 11062(T)) is proposed as a novel species of genus Yarrowia.

Observations of a freshwater pulse induced by Typhoon Morakot off the northern coast of Taiwan in August 2009

Author Posting. © Sears Foundation for Marine Research, 2013. This article is posted here by permission of Sears Foundation for Marine Research for personal use, not for redistribution. The definitive version was published in Journal of Marine Research 71 (2013): 19-46, doi:10.1357/002224013807343452.

Intertidal Assemblages On Artifical Structures And Natural Rocky Habitats On Taiwan'S North Coast

Differences in intertidal assemblages between artifi cial structures and natural rocky habitats require further investigation, so that the potential effects of artifi cial structures on coastal intertidal community can be better understood. We examined the intertidal assemblages on breakwaters, seawalls, and natural rocky shores in the Linshanbi and Houcuo fi shing ports on the northern coast of Taiwan. Nine seawater parameters were measured at each sampling site in Dec.2010, Mar.2011, and Jun.2011. Intertidal assemblages on seawalls were largely distinct from those on breakwaters or natural rocky shores. The taxa that contributed most to the differences among habitats were algae, barnacles, oysters, and limpets. Limpets, red algae, and green algae were less abundant on seawalls compared to breakwaters or the natural rocky shore. Fewer intertidal organisms existed on seawalls than on breakwaters and natural rocky shores. The mobile organisms on breakwaters were similar to those on natural rocky shores. However, during the growing season, a greater number of mobile organisms were found on natural rocky shores than on breakwaters. We suggest that differences in seawater quality, which might relate to the presence of artifi cial structures, could affect the abundance of intertidal organisms. Further information is required on important factors in artifi cial structures that affect intertidal assemblages, in various coastal areas, to help conserve intertidal biodiversity.

Mesozooplankton and copepod community structures in the southern East China Sea: the status during the monsoonal transition period in September

A field sampling was conducted before the onset of the northeasterly monsoon to investigate the copepod community composition during the monsoon transition period at the northern coast of Taiwan (East China Sea). In total, 22 major mesozooplankton taxa were found, with the Calanoida (relative abundance: 66.36%) and Chaetognatha (9.44%) being the most abundant. Mesozooplankton densities ranged between 226.91 and 2162.84 individuals m−3 (mean ± SD: 744.01 ± 631.5 individuals m−3). A total of 49 copepod species were identified, belonging to 4 orders, 19 families, and 30 genera. The most abundant species were: Temora turbinata (23.50%), Undinula vulgaris (17.92%), and Acrocalanus gibber (14.73%). The chaetognath Flaccisagitta enflata occurred at all 8 sampling stations, providing a 95% portion of the overall chaetognath contribution. Amphipoda were abundant at stations 4 and 5, with Hyperioides sibaginis and Lestigonus bengalensis being dominant, and comprising about 50% of all amphipods. Chaetognath abundance showed a significantly negative correlation with salinity (r = 0.77, p = 0.027), whereas mesozooplankton group numbers had a significantly positive correlation with salinity (r = 0.71, p = 0.048). Densities of four copepod species (Calanus sinicus, Calocalanus pavo, Calanopia elliptica and Labidocera acuta) showed a significantly negative correlation with seawater temperature. Communities of mesozooplankton and copepods of northern Taiwan varied spatially with the distance to land. The results of this study provide evidence for the presence of C. sinicus in the coastal area of northern Taiwan during the early northeast monsoon transition period in September.

Trace metals in seawater and copepods in the ocean outfall area off the northern Taiwan coast

The distribution, partitioning and concentrations of trace metals (Cd, Cr, Cu, Fe, Mn, Pb and Zn) in seawater, including dissolved and particulate phases, and in copepods in the ocean outfall area off the northern coast of Taiwan were investigated. Normalization of metal concentrations to the background metal concentration to yield relative enrichment factors (EF), which were used to evaluate the contamination of dissolved and particulate trace metals in seawater around the ocean outfall. The EF results indicated that the outfall area was significantly contaminated by dissolved Fe and Zn, and by particulate Fe, Cr, Cu, Pb and Zn. In addition, most trace metals were chiefly in the particulate phase. The average percentage of total metal concentrations (dissolved plus particulate phases) bound by suspended particulate matter followed the sequence Al(95%) = Mn(95%) > Pb(88%) > Cu(86%) > Fe(72%) > Zn(32%) > Cr(17.5%) > Cd(3.4%). Therefore, metal contamination is better evaluated in solid phase than in the dissolved phase. The concentration ranges of trace metals in the copepods, Temora turbinata, Oncaea venusta and Euchaeta rimana, near the outfall were: Cd, 0.23-1.81 microg g(-1); Cr, 16.5-195 microg g(-1); Cu, 14-160 microg g(-1); Fe, 256-7255 microg g(-1); Mn, 5.5-80.8 microg g(-1); Pb, 2.6-56.2 microg g(-1); Zn, 132-3891 microg g(-1); and Al, 0.21-1.13%. Aluminum, and probably Fe, seemed to be the major elements in copepods. The concentrations of trace metals in copepods, especially Temora turbinata, near the outfall were generally higher than those obtained in the background station. The mean increase in bioconcentration factor of metals in copepods ranged from 4 to 7 and followed the sequence Al(6.4) > Cu(6.2) > Fe(6.0) > Zn(5.7) > Pb(5.6) > Cr(5.5) > Cd(5.1) > Mn(4.7). Therefore, marine copepods in the waters of northern Taiwan can accumulate trace metals over background concentrations and act as contamination indicators.

Effect of Thermal Discharges on the Fish Assemblages of a Nuclear Power Plant in Northern Taiwan

The purpose of this paper is to study whether the thermal plume can affect the fish assemblages in the waters around the outlet area of the Second Nuclear Power Plant located at Kuosheng. a coastline between Yehliu and Chinshan village, northern coast of Taiwan. Both experimental and control stations of underwater census for reef fishes and of drift net sampling for pelagic or demersal fishes above sandy bottom were monitored four times per year from March 2001 to September 2004. The results show that no significant differences were found between the fish assemblages of the thermal waters and normal ambient waters for both coral reef fishes and pelagic or demersal fishes. It was probably due to microhabitat difference rather than water difference because the above fishes are mostly living near bottom where the water temperature are similar to each others for these two stations. On the contrary, the seasonal effect due to low water temperature in the winter had greater influence on the fish assemblages than the effect of thermal plume.