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Coastal forests on sandy beaches in Japan are mainly established by Pinus thunbergii Parl.. These forests prevent and mitigate disasters such as wind, sand, tide, and tsunami. But Pinus thunbergii die-off is progressing nationwide in Japan and the function of coastal forests is declining. Therefore, a multi-tiered forest has been proposed composed of Pinus thunbergii and broadleaf trees instead of Pinus thunbergii trees. However, few studies have quantitatively evaluated the shade-tolerance characteristics of the broadleaf trees that comprise these forests. To this end, we measured chlorophyll levels (SPAD value) in eight representative evergreen broadleaf tree species inhabiting coastal areas in Japan and evaluated their shade-tolerance. [ABSTRACT FROM AUTHOR]

Tidal freshwater forests are usually located at or above the level of mean high water. Some Louisiana coastal forests are below mean high water, especially bald cypress (Taxodium distichum (L.) Rich.) forests because flooding has increased due to the combined effects of global sea level rise and local subsidence. In addition, constructed channels from the coast inland act as conduits for saltwater. As a result, saltwater intrusion affects the productivity of Louisiana's coastal bald cypress forests. To study the long-term effects of hydrology and salinity on the health of these systems, we fitted dendrometer bands on selected trees to record basal area increment as a measure of growth in permanent forest productivity plots established within six bald cypress stands. Three stands were in freshwater sites with low salinity rooting zone groundwater (0.1–1.3 ppt), while the other three had higher salinity rooting zone groundwater (0.2–4.9 ppt). Water level was logged continuously, and salinity was measured monthly to quarterly on the surface and in groundwater wells. Higher groundwater salinity levels were related to decreased bald cypress radial growth, while higher freshwater flooding increased radial growth. With these data, coastal managers can model rates of bald cypress forest change as a function of salinity and flooding. [ABSTRACT FROM AUTHOR]

French Guiana is a French overseas territory located in northern South America. Here we report the first record of Scarthyla goinorum (Bokermann, 1962) from this territory, which represents a range extension of 450 km northward from the nearest previously known occurrence in Amapá state, Brazil. This is also the first occurrence outside the Amazon Basin and indicates the ability of the species to disperse efficiently to other watersheds possibly via floating rafts drifting along the coast.

This investigation evaluated two fundamental assumptions of wetland inundation models designed to emulate landscape evolution and resiliency under conditions of sea level rise: that they can (1) migrate landward at the same rate as the transgressing shoreline and (2) immediately replace the plant community into which they are onlapping. Rates of wetland (e.g., marsh, mangrove) migration were culled from 11 study areas located in five regions of focus: Delaware Bay, Chesapeake Bay, Pamlico Sound, South Florida, and Northwest Florida. The average rate of marsh migration (n = 14) was 3.7 m yr−1. The average rate of South Florida mangrove migration (n = 4) was 38.0 m yr−1. The average rate of upland forest retreat (n = 4) was 3.4 m yr−1. Theoretical rates of shoreline transgression were calculated using site-specific landscape slope and scenario-based NOAA sea level rise elevations in 2050. Rates of shoreline transgression over the marsh landscape averaged 94 m yr−1. The average rate of shoreline transgression in the mangrove-dominated areas of South Florida was 153.2 m yr−1. The calculated rates of shoreline transgression were much faster than the observed horizontal marsh migration, and by 2050, the offset or gap between them averaged 2700 m and ranged between 292 and 5531 m. In South Florida, the gap average was 3516 m and ranged between 2766 m and 4563 m. At sites where both horizontal marsh migration and forest retreat rates were available, the distance or gap between them in 2050 averaged 47 m. Therefore, the results of this study are inconsistent with the two fundamental assumptions of many wetland inundation models and suggest that they may overestimate their resilience under conditions of 21st century accelerating sea level rise.

This review paper provides a comprehensive analysis of utilizing coastal vegetation as a mitigation strategy against tsunamis. It begins with an introduction to the historical impact of tsunamis on coastal vegetation and explores various types of trees known for their tsunami defense characteristics. The paper examines how vegetation can effectively protect against tsunamis based on past events, supported by both experimental and numerical studies. It also delves into innovative concepts proposed by researchers, including hybrid defense systems and optimized plantation layouts, to enhance the protective capabilities of coastal vegetation. Case studies from Aceh and South Java illustrate practical applications of reforestation efforts aimed at tsunami mitigation. Additionally, the paper discusses the challenges and limitations associated with implementing coastal vegetation strategies, emphasizing crucial factors such as maintenance and long-term sustainability.

This study explores how Pacitan Bay, Indonesia's coastal vegetation, can help mitigate tsunamis. It combines numerical modelling and field observations to assess the role and performance of vegetation while addressing the existing vegetated occupancy and gap between sectors. The study utilises simulations and on-site data to evaluate how coastal vegetation reduces tsunami wave energy and enhances coastal resilience. The findings emphasise the importance of vegetation as a natural defence against tsunamis in Pacitan Bay and highlight the need to address the open gap. This research offers valuable insights for coastal management, improving future strategies for effective tsunami mitigation. Research highlights: The research confirms the effectiveness of using a nested grid pattern to accurately simulate tsunamis in intricate coastal areas, showcasing successful grid transitions and propagation of reflected waves. The role of coastal vegetation in reducing the impact of tsunamis is vital, as larger forested areas and denser vegetation result in more effective wave reduction. Challenges faced by coastal vegetation in Pacitan Bay encompass soil quality, microclimate conditions, land-use changes, and threats such as illegal logging and natural events. Addressing these challenges requires a combination of policies, enforcement, community-based initiatives, and collaboration to enhance coastal resilience and maintain a thriving ecosystem. [ABSTRACT FROM AUTHOR]

This investigation evaluated two fundamental assumptions of wetland inundation models designed to emulate landscape evolution and resiliency under conditions of sea level rise: that they can (1) migrate landward at the same rate as the transgressing shoreline and (2) immediately replace the plant community into which they are onlapping. Rates of wetland (e.g., marsh, mangrove) migration were culled from 11 study areas located in five regions of focus: Delaware Bay, Chesapeake Bay, Pamlico Sound, South Florida, and Northwest Florida. The average rate of marsh migration (n = 14) was 3.7 m yr−1. The average rate of South Florida mangrove migration (n = 4) was 38.0 m yr−1. The average rate of upland forest retreat (n = 4) was 3.4 m yr−1. Theoretical rates of shoreline transgression were calculated using site-specific landscape slope and scenario-based NOAA sea level rise elevations in 2050. Rates of shoreline transgression over the marsh landscape averaged 94 m yr−1. The average rate of shoreline transgression in the mangrove-dominated areas of South Florida was 153.2 m yr−1. The calculated rates of shoreline transgression were much faster than the observed horizontal marsh migration, and by 2050, the offset or gap between them averaged 2700 m and ranged between 292 and 5531 m. In South Florida, the gap average was 3516 m and ranged between 2766 m and 4563 m. At sites where both horizontal marsh migration and forest retreat rates were available, the distance or gap between them in 2050 averaged 47 m. Therefore, the results of this study are inconsistent with the two fundamental assumptions of many wetland inundation models and suggest that they may overestimate their resilience under conditions of 21st century accelerating sea level rise. [ABSTRACT FROM AUTHOR]

Sea level rise and storm surges drive coastal forest retreat and salt marsh expansion. Both salinization and flooding control ecological zonation and ecosystem transition in coastal areas. Hydrological variables, if coupled with ecological surveys, can explain the different stages of coastal forest retreat and marsh encroachment. In this research, long‐term data of a host of hydrological variables collected along transects from marsh to inner forest were analyzed. Linear discriminant analysis (LDA) was used to identify the primary hydrological variables responsible for the forest‐marsh gradient and their seasonal patterns. Water content (WC) in the soil (WC) and groundwater electrical conductivity (EC) were found to be the main variables responsible for the hydrological differences among the sites. Higher values of WC and EC were found in the low‐forest area near the salt marsh, with hydrological differences between forest levels reflected in ecological community structure. In particular, some sites were characterized by high EC while others by high WC values, suggesting significant spatial variations within hundreds of meters. The forested area, relatively flat in elevation, was characterized by limited hydraulic gradients and consequently lateral discharges. These characteristics made the role of groundwater level negligible in driving the hydrological clustering. Seasonal LDA data suggest that the sites are hydrologically different during winter (higher distance among clusters of variables) and similar during summer (low distance among clusters). In the study area, higher rainfall occurs during summer, decreasing groundwater EC in areas characterized by low canopy cover (dying forest). Rainfall moved low forest sites closer to the pristine high forest in the LDA analysis. During storm surge events, the distance between clusters decreased, indicating uniform salinization and flooding across the forest. Therefore, we conclude that ecological zonation in a coastal forest is reflected in seasonal hydrological differences in the absence of storm surges. Storm surges do not produce contrasting hydrological conditions and might not be responsible for ecological differences in the short‐term. On the contrary, differences in hydrological recovery are responsible for forest zonation. An additional analysis carried out using a binary Marsh‐Healthy forest LDA classifier indicates when each site switches from a forest hydrological state to a salt‐marsh hydrological state. Our results are useful for long‐term predictions of the ecological evolution of the forest–salt marsh ecotone. Key Points: Linear discriminant analysis was used to cluster hydrological variables in a coastal forest affected by sea level rise (SLR) and storm surgesHydrological clustering was related to ecological characteristicsStorm surges tend to homogenize the hydrological variables across the study site, while in winter spatial gradients are present [ABSTRACT FROM AUTHOR]

Tidal freshwater forests are usually located at or above the level of mean high water. Some Louisiana coastal forests are below mean high water, especially bald cypress (Taxodium distichum (L.) Rich.) forests because flooding has increased due to the combined effects of global sea level rise and local subsidence. In addition, constructed channels from the coast inland act as conduits for saltwater. As a result, saltwater intrusion affects the productivity of Louisiana’s coastal bald cypress forests. To study the long-term effects of hydrology and salinity on the health of these systems, we fitted dendrometer bands on selected trees to record basal area increment as a measure of growth in permanent forest productivity plots established within six bald cypress stands. Three stands were in freshwater sites with low salinity rooting zone groundwater (0.1–1.3 ppt), while the other three had higher salinity rooting zone groundwater (0.2–4.9 ppt). Water level was logged continuously, and salinity was measured monthly to quarterly on the surface and in groundwater wells. Higher groundwater salinity levels were related to decreased bald cypress radial growth, while higher freshwater flooding increased radial growth. With these data, coastal managers can model rates of bald cypress forest change as a function of salinity and flooding.

Coastal forests can increase the resilience of seaside communities against natural disasters. These forests also provide other benefits, including food and an avenue for economic growth. The Dakenggu community in Suao, Yilan (Taiwan), is adjacent to a coastal forest with an area of nearly 114,000 m2. Artificial plantation has been performed locally in this area since 1977 to prevent the loss of beaches. The coastal forest area was estimated through drone aerial photography combined with a geographic information system. We found that Pandanus tectorius (11.5%), Casuarina equisetifolia (30.8%), Cerbera manghas (4.07%), Hibiscus tiliaceus (5.2%), and grass (23.52%) are the dominant species in the plant community of Dakenngu coastal forest, which together accounted for 75.1% of the total land area. The area covered by different species in the coastal forest was examined and estimated as well. The height and diameter at breast height (DBH) of the main tree species in five transects were surveyed, and we also found some significant differences among transects that correspond to cohorts planted at different times by the Forestry Bureau. We also performed a survey of land crabs in the same transects over five months to infer any differences in land crab species among the transects. We found that the transect dominated by H. tiliaceus had a larger population of land crabs than others. We revealed that the mudflat crab Chiromantes haematocheir prefers to live under H. tiliaceus. Finally, we propose recommendations for improving the biodiversity of the Dakenggu coastal forest so that it can become a sustainable resource for its residents. [ABSTRACT FROM AUTHOR]

A Popular Scientific Book (PSB), which mainly contains 12 species of herbs that grow in the Tabanio Coastal Forest, Tanah Laut Regency, has been compiled, but its practicality has not been determined. The research aims to determine the practicality of the book. The determination is based on the results of the readability test, implementation, and response to the PSB. The subject is a student who has taken a course in Higher Plant Botany (Phanerogamae). Readability was tested one on one by three subjects. Implementation was observed by 5 observers who assessed implementation by small groups (5 subjects) and also by field groups (10 subjects). The instrument is a questionnaire with 9 statements. Responses to PSB were also obtained from small groups consisting of 5 subjects and field groups with 10 subjects. The questionnaire instrument consists of 15 statements. The readability value is 94.23% or categorized as Very Good. The value of the implementation of expectations originating from the small group is 91.11% and the actual implementation of the field group is 92.22%. These two values are categorized as Very Good and seem steady. Expected response values and actual responses are 87.20% and 88.40%, respectively. Both of these response values are categorized as Strongly Agree and also steady. Based on the test results, overall this PSB is practically used with the consideration that any deficiencies found are always revised. Abstrak Buku Ilmiah Popular (BIP) yang konten utamanya 12 spesies herba yang tumbuh di Hutan Pantai Tabanio, Kabupaten Tanah Laut sudah disusun, tetapi kepraktisannya belum ditentukan. Penelitian bertujuan untuk menentukan kepraktisan buku tersebut. Penentuannya berdasarkan pada hasil uji keterbacaan, keterlaksanaan, dan respons terhadap BIP. Subjeknya adalah mahasiswa yang pernah mengambil mata kuliah Botani Tumbuhan Tinggi (Phanerogamae). Keterbacaan diuji satu lawan satu oleh tiga subjek. Keterlaksanaan diamati oleh 5 pengamat yang menilai pelaksanaan oleh kelompok kecil (5 subjek) dan juga oleh kelompok lapangan (10 subjek). Instrumennya berupa angket dengan 9 pernyataan. Respons terhadap BIP diperoleh juga dari kelompok kecil yang terdiri atas 5 subjek dan kelompok lapangan dengan 10 subjek. Instrumen angketnya terdiri atas 15 pernyataan. Nilai keterbacaan adalah 94,23% atau terkategori Sangat Baik. Nilai keterlaksanaan harapan yang bersumber dari kelompok kecil adalah 91,11% dan keterlaksanaan aktual dari kelompok lapangan 92,22%. Kedua nilai ini dikategorikan Sangat Baik dan terkesan ajeg. Nilai respons harapan dan respons aktual berturut-turut adalah 87,20% dan 88,40%. Kedua nilai respons ini terkategori Sangat Setuju dan juga bersifat ajeg. Berdasarkan pada hasil uji itu, secara keseluruhan BIP ini praktis digunakan dengan pertimbangan bahwa segala kekurangan yang ditemukan selalu direvisi.

Casuarina equisetifolia L. plays a significant role in sandy, coastal regions for sand stabilization and windbreaks. However, C. equisetifolia forests are susceptible to plant diseases and insect pests, resulting in mortality due to pure stands and a harsh natural environment. Mapping the distribution of C. equisetifolia and detecting its height can inform forest-management decisions. Unmanned aerial vehicle (UAV) imagery, coupled with the classical detection method, can provide accurate information on tree-level forest parameters. Considering that the accuracy of a forest-parameter estimation is impacted by various flight altitudes and extraction parameters, the purpose of this study is to determine the appropriate flight altitude and extraction parameters for mapping C. equisetifolia using UAV imagery and the local maxima algorithm in order to monitor C. equisetifolia more accurately. A total of 11 different flight altitudes and 36 combinations of circular smoothing window size (CSWS) and fixed circular window size (FCWS) were tested, and 796 trees with corresponding positions in the UAV image and ground–tree heights were used as reference. The results show that the combination of a 0.1 m CSWS and a 0.8 m FCWS for individual tree detection (ITD) and tree-height detection achieved excellent accuracy (with an F1 score of 91.44% for ITD and an estimation accuracy (EA) of 79.49% for tree-height detection). A lower flight altitude did not indicate a higher accuracy for individual tree and tree-height detection. The UAV image obtained within a flight altitude of 60 m–80 m can meet the accuracy requirements for the identification of C. equisetifolia tree-height estimation (F1 score > 85% for ITD; EA > 75% for tree-height estimation). This study provides a foundation for monitoring C. equisetifolia by using UAV imagery and applying the local maxima algorithm, which may help forestry practitioners detect C. equisetifolia trees and tree heights more accurately, providing more information on C. equisetifolia growth status. [ABSTRACT FROM AUTHOR]

Abstract The distributions of sandy tsunami deposits do not reflect the true extents of tsunami inundation areas, leading to underestimates of inundation by past tsunamis and thus the magnitudes of their associated tsunamigenic earthquakes. To archive the sedimentological and geochemical features of the 2011 Tohoku-oki tsunami deposit, we performed visual observations and computed tomography, grain-size, water content, and organic geochemical analyses of sediments from a coastal forest at Oirase Town, northern Japan. Stratigraphic observations revealed the 2011 tsunami deposit to be a landward-thinning interbedded sand and soil layer that became ambiguous in landward locations. The sediment samples from the inundated area did not contain marine-sourced biomarkers; instead, peak concentrations of isolongifolene, an organic compound derived from Pinus in the forest, were observed within or just above the sandy tsunami deposits in sediment sections. Peak isolongifolene concentrations were also detected in landward soils inundated by the tsunami in which no sand layer was observable, but were not observed beyond the inundation limit. Although this characteristic biomarker is unique to this and similar depositional environments, these results suggest that lateral changes of the concentrations of environment-specific biological proxies in the sedimentary column may record tsunami inundation.

Crab-eating mongooses (Herpestes urva) are widely distributed across Southeast Asia. In Taiwan, the mongoose (H. urva formosanus, endemic subspecies) is a protected species under the Wildlife Protection Act. Crab-eating mongooses have been observed near streams, riversides, agricultural lands, and shallow mountain areas. Additionally, as described in this short communication, by using a remote camera, we observed a small population of mongooses in the coastal forest in Kenting National Park in Taiwan. The mongooses in the coastal forest were observed eating land hermit crabs, which is the first-ever recorded observation of this behavior. Mongooses are known to consume crabs (Brachyura), insects, and some small reptiles. However, this article presents the first record case of mongooses using stone anvil to crack open land hermit crabs. From our observations and field records, we determined that mongooses use flat rocks as anvils and their front paws to tap hermit crabs' shells repeatedly to break the shells and remove the hermit crabs. We also observed that the mongooses only ate the abdomens of large hermit crabs. Additional studies are necessary to determine why the mongooses migrated to the coastal forest and how they learned to open hermit crab shells. This behavior of mongooses might help them move into living in coastal forests. [ABSTRACT FROM AUTHOR]

Summary: Increasing seawater exposure is killing coastal trees globally, with expectations of accelerating mortality with rising sea levels. However, the impact of concomitant changes in atmospheric CO2 concentration, temperature, and vapor pressure deficit (VPD) on seawater‐induced tree mortality is uncertain.We examined the mechanisms of seawater‐induced mortality under varying climate scenarios using a photosynthetic gain and hydraulic cost optimization model validated against observations in a mature stand of Sitka spruce (Picea sitchensis) trees in the Pacific Northwest, USA, that were dying from recent seawater exposure.The simulations matched well with observations of photosynthesis, transpiration, nonstructural carbohydrates concentrations, leaf water potential, the percentage loss of xylem conductivity, and stand‐level mortality rates. The simulations suggest that seawater‐induced mortality could decrease by c. 16.7% with increasing atmospheric CO2 levels due to reduced risk of carbon starvation. Conversely, rising VPD could increase mortality by c. 5.6% because of increasing risk of hydraulic failure.Across all scenarios, seawater‐induced mortality was driven by hydraulic failure in the first 2 yr after seawater exposure began, with carbon starvation becoming more important in subsequent years. Changing CO2 and climate appear unlikely to have a significant impact on coastal tree mortality under rising sea levels. [ABSTRACT FROM AUTHOR]

Coastal forests can increase the resilience of seaside communities against natural disasters. These forests also provide other benefits, including food and an avenue for economic growth. The Dakenggu community in Suao, Yilan (Taiwan), is adjacent to a coastal forest with an area of nearly 114,000 m2. Artificial plantation has been performed locally in this area since 1977 to prevent the loss of beaches. The coastal forest area was estimated through drone aerial photography combined with a geographic information system. We found that Pandanus tectorius (11.5%), Casuarina equisetifolia (30.8%), Cerbera manghas (4.07%), Hibiscus tiliaceus (5.2%), and grass (23.52%) are the dominant species in the plant community of Dakenngu coastal forest, which together accounted for 75.1% of the total land area. The area covered by different species in the coastal forest was examined and estimated as well. The height and diameter at breast height (DBH) of the main tree species in five transects were surveyed, and we also found some significant differences among transects that correspond to cohorts planted at different times by the Forestry Bureau. We also performed a survey of land crabs in the same transects over five months to infer any differences in land crab species among the transects. We found that the transect dominated by H. tiliaceus had a larger population of land crabs than others. We revealed that the mudflat crab Chiromantes haematocheir prefers to live under H. tiliaceus. Finally, we propose recommendations for improving the biodiversity of the Dakenggu coastal forest so that it can become a sustainable resource for its residents.

The distributions of sandy tsunami deposits do not reflect the true extents of tsunami inundation areas, leading to underestimates of inundation by past tsunamis and thus the magnitudes of their associated tsunamigenic earthquakes. To archive the sedimentological and geochemical features of the 2011 Tohoku-oki tsunami deposit, we performed visual observations and computed tomography, grain-size, water content, and organic geochemical analyses of sediments from a coastal forest at Oirase Town, northern Japan. Stratigraphic observations revealed the 2011 tsunami deposit to be a landward-thinning interbedded sand and soil layer that became ambiguous in landward locations. The sediment samples from the inundated area did not contain marine-sourced biomarkers; instead, peak concentrations of isolongifolene, an organic compound derived from Pinus in the forest, were observed within or just above the sandy tsunami deposits in sediment sections. Peak isolongifolene concentrations were also detected in landward soils inundated by the tsunami in which no sand layer was observable, but were not observed beyond the inundation limit. Although this characteristic biomarker is unique to this and similar depositional environments, these results suggest that lateral changes of the concentrations of environment-specific biological proxies in the sedimentary column may record tsunami inundation. [ABSTRACT FROM AUTHOR]

Casuarina equisetifolia L. plays a significant role in sandy, coastal regions for sand stabilization and windbreaks. However, C. equisetifolia forests are susceptible to plant diseases and insect pests, resulting in mortality due to pure stands and a harsh natural environment. Mapping the distribution of C. equisetifolia and detecting its height can inform forest-management decisions. Unmanned aerial vehicle (UAV) imagery, coupled with the classical detection method, can provide accurate information on tree-level forest parameters. Considering that the accuracy of a forest-parameter estimation is impacted by various flight altitudes and extraction parameters, the purpose of this study is to determine the appropriate flight altitude and extraction parameters for mapping C. equisetifolia using UAV imagery and the local maxima algorithm in order to monitor C. equisetifolia more accurately. A total of 11 different flight altitudes and 36 combinations of circular smoothing window size (CSWS) and fixed circular window size (FCWS) were tested, and 796 trees with corresponding positions in the UAV image and ground–tree heights were used as reference. The results show that the combination of a 0.1 m CSWS and a 0.8 m FCWS for individual tree detection (ITD) and tree-height detection achieved excellent accuracy (with an F1 score of 91.44% for ITD and an estimation accuracy (EA) of 79.49% for tree-height detection). A lower flight altitude did not indicate a higher accuracy for individual tree and tree-height detection. The UAV image obtained within a flight altitude of 60 m–80 m can meet the accuracy requirements for the identification of C. equisetifolia tree-height estimation (F1 score > 85% for ITD; EA > 75% for tree-height estimation). This study provides a foundation for monitoring C. equisetifolia by using UAV imagery and applying the local maxima algorithm, which may help forestry practitioners detect C. equisetifolia trees and tree heights more accurately, providing more information on C. equisetifolia growth status.

According to the categorization of the World Wide Fund for Nature (WWF, for its acronym in English), xeromorphic scrublands are terrestrial ecoregions of importance for conservation. In order to characterize the floristic composition and structure of a coastal and subcoastal xeromorphic scrub, the following study was developed, at the "El Rosal" site located in the semi-arid zone of the Guantánamo province. Twenty sampling plots with an area of 20 x 25 m were established; the diameter (1.30) and height of all individuals e" 5 cm were recorded, the sampling was validated with the area-species curve. With the values obtained, the Shannon, equity and Simpson diversity indices and beta diversity were calculated through an analysis of hierarchical clusters, by means of the Sorensen distance measure, the horizontal structure and the vertical structure through the description of the strata. of the vegetation. A total of 15 species belonging to 10 genera and 11 families were recorded, where the species of greatest ecological importance were Guaiacum officinale L. and Leucaena leucocephala (Lam.) de Wit. In the cluster analysis, three clusters were distinguished with 63 % similarity. Low floristic diversity was demonstrated and the vegetation reached up to 5 m in dominant height and the species with the highest sociological position were Guaiacum officinale, Leucaena leucocephala and Azadirachta indica. [ABSTRACT FROM AUTHOR]

Abstract Background Because ixodid ticks are vectors of zoonotic pathogens, including Borrelia, information of their abundance, seasonal variation in questing behaviour and pathogen prevalence is important for human health. As ticks are invading new areas northwards, information from these new areas are needed. Taiga tick (Ixodes persulcatus) populations have been recently found at Bothnian Bay, Finland. We assessed seasonal variation in questing abundance of ticks and their pathogen prevalence in coastal deciduous forests near the city of Oulu (latitudes 64–65°) in 2019. Methods We sampled ticks from May until September by cloth dragging 100 meters once a month at eight study sites. We calculated a density index (individuals/100 m2) to assess seasonal variation. Samples were screened for Borrelia burgdorferi (sensu lato) (including B. afzelii, B. garinii, B. burgdorferi (sensu stricto) and B. valaisana), Borrelia miyamotoi, Anaplasma phagocytophilum, Rickettsia spp., Neoehrlichia mikurensis, Francisella tularensis and Bartonella spp., Babesia spp. and for the tick-borne encephalitis virus. Results All except one nymph were identified as I. persulcatus. The number of questing adults showed a strong peak in May (median: 6.5 adults/100 m2), which is among the highest values reported in northern Europe, and potentially indicates a large population size. After May, the number of questing adults declined steadily with few adults still sampled in August. Nymphs were present from May until September. We found a striking prevalence of Borrelia spp. in adults (62%) and nymphs (40%), with B. garinii (51%) and B. afzelii (63%) being the most common species. In addition, we found that 26% of infected adults were coinfected with at least two Borrelia genospecies, mainly B. garinii and B. afzelii, which are associated with different host species. Conclusions The coastal forest environments at Bothnian Bay seem to provide favourable environments for I. persulcatus and the spread of Borrelia. High tick abundance, a low diversity of the host community and similar host use among larvae and nymphs likely explain the high Borrelia prevalence and coinfection rate. Research on the infestation of the hosts that quantifies the temporal dynamics of immature life stages would reveal important aspects of pathogen circulation in these tick populations.

Green infrastructure, utilizing coastal ecosystems, provides a nature-based solution to counteract coastal hazards and rising sea level. Coastal forests, a major type of green infrastructure, are recognized as natural barriers against ocean waves. They can attenuate waves, mitigate erosion, and stabilize shorelines. With growing interests in coastal forests and their function of adapting to future risks, many researchers studied vegetation effects in coastal protection. Yet our limited expertise in quantifying vegetation-induced resistance limits the practical applications. This paper aims to review and categorize the studies related to wave attenuation and mitigation of sediment erosion by coastal forests and identify the potential directions in future works. We first reviewed field observations of extreme tsunami and weather events which showed the effectiveness of coastal forests in reducing wave energy. Next, we covered the studies on wave–vegetation interaction, including mathematical/numerical models and laboratory tests. We categorized the developed models based on different governing equations and introduced how vegetation effects were incorporated. We also discussed the experiments and vegetation models used in laboratory tests. Besides, we highlighted recent studies on the mitigation of coastal erosion. Finally, we recommend the potential directions to quantify the effects of coastal forests on wave attenuation and sedimentation. [ABSTRACT FROM AUTHOR]

Coastal salt marshes, which provide valuable ecosystem services such as flood mitigation and carbon sequestration, are threatened by rising sea level. In response, these ecosystems migrate landward, converting available upland into salt marsh. In the coastal-plain surrounding Chesapeake Bay, United States, conversion of coastal forest to salt marsh is well-documented and may offset salt marsh loss due to sea level rise, sediment deficits, and wave erosion. Land slope at the marsh-forest boundary is an important factor determining migration likelihood, however, the standard method of using field measurements to assess slope across the marsh-forest boundary is impractical on the scale of an estuary. Therefore, we developed a general slope quantification method that uses high resolution elevation data and a repurposed shoreline analysis tool to determine slope along the marsh-forest boundary for the entire Chesapeake Bay coastal-plain and find that less than 3% of transects have a slope value less than 1%; these low slope environments offer more favorable conditions for forest to marsh conversion. Then, we combine the bay-wide slope and elevation data with inundation modeling from Hurricane Isabel to determine likelihood of coastal forest conversion to salt marsh. This method can be applied to local and estuary-scale research to support management decisions regarding which upland forested areas are more critical to preserve as available space for marsh migration.

Purpose: To restore the disaster resilience of coastal forests in tsunami-prone areas, growing bases have been artificially constructed with embanking before afforestation to increase the effective soil depth and allow deeper root system development. The aim of the present study was to describe and record the soil features of these anthropogenic growing bases and root development within them to provide guidance on their construction and comprehensively evaluate their potential for disaster resilience. Materials and methods: Soil surveys including root excavation were conducted on anthropogenic growing bases in coastal forests including seaside parks in the Kanto and Tohoku regions of Japan. All of the soils assessed were classified as "Spolic (Subaquatic)" or "Urbic" Technosols because they contained artefacts with large amounts of industrial soil materials in their profiles. Soil samples were taken from each horizon in the soil profiles using 400-ml and/or 100-ml cylinders, and the undisturbed cylinder samples were then analyzed to determine the bulk density, water permeability, and porosity of the soils at each site. The vertical distribution of soil hardness in the anthropogenic growing bases was also measured using a dynamic cone penetrometer. Results and discussion: Some of the growing bases were generally soft with high water permeability, indicating that soil improvements such as deep tillage were quite effective for building suitable growing bases. Notably, some vestiges of pedogenic processes would be partly recognized throughout the soil profile of an old growing base after construction. However, some embankments had serious issues in the growing base soil, including thick and continuous planar consolidated pan layers with quite low permeability and vestiges of strong gleyzation in their profiles. These poor soil conditions inhibited plant growth, particularly of the below ground roots, and remained in the growing bases for a long time. Conclusions: The study indicated quantitatively that (1) the physical properties of anthropogenic soils constructed using heavy machinery could be maintained for several decades, and (2) compaction should be avoided during soil preparation to avoid soil hardening, water stagnation, and hindrance of root penetration. Although these findings unfortunately lack quantitative consideration of the requirements for stabilizing embankments, they reinforce awareness of the difficulty of constructing anthropogenic soils to foster the growth of trees and provide sufficient strength for embanked foundations. This topic requires further study. [ABSTRACT FROM AUTHOR]

The endangered golden‐rumped sengi are found only in Arabuko‐Sokoke Forest with 395.4 km2 of forest habitat, and perhaps in a few isolated forest and thicket fragments of total area less than 30 km2 all within central coastal Kenya. Understanding its habitat use is an important requirement to develop better conservation measures for the species and its remaining forest habitat. A more reliable method for monitoring its status is also needed. We used the Bayesian occupancy modelling with camera trap data and habitat mapping to characterise the species habitat use in the Arabuko‐Sokoke Forest. The species uses 328 km2 (95% CI: 289–364 km2) of Arabuko‐Sokoke Forest habitat, and its site use increases with distance from forest edge, with the highest site use in the Cynometra thicket (0.93; 95% CI: 0.82–1). Its use of the mixed forest habitat has been significantly reduced following years of logging of Afzelia quanzensis. We recommend the use of modelled occupancy, interpreted as the proportion of area used by the species, to monitor the species status. Occupancy models account for detection probability, and heterogeneity in site use and detection can be incorporated. Estimated territory sizes can be combined to obtain abundance estimates. [ABSTRACT FROM AUTHOR]

Methane (CH4) exchange between trees and the atmosphere has recently emerged as an important, but poorly quantified process regulating global climate. The sources (soil and/or tree) and mechanisms driving the increase of CH4 in trees and degassing to the atmosphere are inadequately understood, particularly for coastal forests facing increased exposure to seawater. We investigated the eco‐physiological relationship between tree stem wood density, soil and stem oxygen saturation (an indicator of redox state), soil and stem CH4 concentrations, soil and stem carbon dioxide (CO2) concentrations, and soil salinity in five forests along the United States coastline. We aim to evaluate the mechanisms underlying greenhouse gas increase in trees and the influence of seawater exposure on stem CH4 accumulation. Seawater exposure corresponded with decreased tree survival and increased tree stem methane. Tree stem wood density was significantly correlated with increased stem CH4 in seawater exposed gymnosperms, indicating that dying gymnosperm trees may accumulate higher levels of CH4 in association with seawater flooding. Further, we found that significant differences in seawater exposed and unexposed gymnosperm tree populations are associated with increased soil and stem CH4 and CO2, indicating that seawater exposure significantly impacts soil and stem greenhouse gas abundance. Our results provide new insight into the potential mechanisms driving tree CH4 accumulation within gymnosperm coastal forests. Plain Language Summary: Trees emit greenhouse gases such as methane and carbon dioxide to the atmosphere. The origin of these gases includes production in the tree or in the surrounding soils. Disturbances to these systems, such as seawater exposure that increases soil salinity, have an unknown impact on gas production and connectivity between soil and trees. We found that higher soil salinities corresponded to higher soil methane content and increased stem methane. The accumulation of soil and tree methane was lower in sites with no salinity exposure and higher in sites with high salinity. As coastal systems become more vulnerable to changes in seawater exposure, this may have consequences on methane emitted from trees to the atmosphere. Key Points: Seawater exposure significantly increased internal stem CH4 concentrationThere is a significant correlation between stem wood density and stem CH4 concentrationLow stem and soil O2 were significantly linked to seawater exposure and decreased tree survival [ABSTRACT FROM AUTHOR]

Background: Because ixodid ticks are vectors of zoonotic pathogens, including Borrelia, information of their abundance, seasonal variation in questing behaviour and pathogen prevalence is important for human health. As ticks are invading new areas northwards, information from these new areas are needed. Taiga tick (Ixodes persulcatus) populations have been recently found at Bothnian Bay, Finland. We assessed seasonal variation in questing abundance of ticks and their pathogen prevalence in coastal deciduous forests near the city of Oulu (latitudes 64–65°) in 2019. Methods: We sampled ticks from May until September by cloth dragging 100 meters once a month at eight study sites. We calculated a density index (individuals/100 m2) to assess seasonal variation. Samples were screened for Borrelia burgdorferi (sensu lato) (including B. afzelii, B. garinii, B. burgdorferi (sensu stricto) and B. valaisana), Borrelia miyamotoi, Anaplasma phagocytophilum, Rickettsia spp., Neoehrlichia mikurensis, Francisella tularensis and Bartonella spp., Babesia spp. and for the tick-borne encephalitis virus. Results: All except one nymph were identified as I. persulcatus. The number of questing adults showed a strong peak in May (median: 6.5 adults/100 m2), which is among the highest values reported in northern Europe, and potentially indicates a large population size. After May, the number of questing adults declined steadily with few adults still sampled in August. Nymphs were present from May until September. We found a striking prevalence of Borrelia spp. in adults (62%) and nymphs (40%), with B. garinii (51%) and B. afzelii (63%) being the most common species. In addition, we found that 26% of infected adults were coinfected with at least two Borrelia genospecies, mainly B. garinii and B. afzelii, which are associated with different host species. Conclusions: The coastal forest environments at Bothnian Bay seem to provide favourable environments for I. persulcatus and the spread of Borrelia. High tick abundance, a low diversity of the host community and similar host use among larvae and nymphs likely explain the high Borrelia prevalence and coinfection rate. Research on the infestation of the hosts that quantifies the temporal dynamics of immature life stages would reveal important aspects of pathogen circulation in these tick populations. [ABSTRACT FROM AUTHOR]

After the 2011 Great East Japan tsunami, field observations have shown the possibility of an inland forest trapping tsunami-borne large driftwood (TLD). This research was conducted to understand the driftwood trapping capability by a forest patch downstream of a shoreline, considering a model scale driftwood with attention to the crown and roots of a tree. The results demonstrated that there are four types that driftwood gets trapped by an inland forest, with each trapping type exhibiting a different force on the trapping tree. A trapping type where the driftwood got trapped at the front face of an inland forest model (IFM) in a cross-stream position by one or more trunk(s) (Type FC) exhibited high force on the trunk, because of the high cross-sectional area of the driftwood against the flow. However, when the upstream trees' (potential to being TLD) trunk length was small, the occurrence of this trapping type decreased. The results showed that the trunk length to tree height ratio of 0.18 had a trapping occurrence of 33%, while trunk length to tree height ratio of 0.06 had a trapping occurrence of 16%. The driftwood condition, in this case, was driftwood with roots. This study further demonstrated the behaviour of driftwood trapping by an inland forest and proposed a further improvement to tsunami mitigation, by elucidating its ability to trap tsunami-generated large driftwood as a function of trunk diameter at breast height. [ABSTRACT FROM AUTHOR]

As sea levels rise, low-lying coastal forests increasingly are subject to stressors such as inundation and saltwater exposure. At long timescales (for example, centuries), the extent of inundation and saltwater exposure will increase; however, on a decadal timescale, the role of these drivers may differ in both magnitude and direction. To investigate the drivers of decadal-scale vegetation change, we measured the changes in five metrics of vegetation composition and structure between 2003/2004 and 2016/2017 at 98 plots distributed across a vegetation gradient from coastal forest to brackish marshes (< 0.5–18 ppt). We used elevation as a proxy of inundation vulnerability and soil sodium concentration as a proxy of saltwater exposure, and we investigated relationships between these two variables and the change in vegetation conditions between the two sampling periods. Soil sodium concentration was a significant predictor of vegetation change for all five vegetation metrics, whereas the effect of elevation was not significant for any of the metrics. The one site that was affected by wildfire twice during the duration of the study shifted almost completely from forest to marsh with limited regeneration of woody vegetation observed in 2016/2017. Our results show that salinization in our system is a more important driver of vegetation change than inundation potential. Furthermore, the effects of drought-induced salinization could be amplified by the elevated risk of wildfire during droughts. Forecasting the response of coastal wetlands to rising sea levels will require a better understanding of the individual and combined effects of salinity, droughts, and wildfires on vegetation. [ABSTRACT FROM AUTHOR]

Maritime forests are threatened by sea-level rise, storm surge and encroachment of salt-tolerant species. On barrier islands, these forested communities must withstand the full force of tropical storms, hurricanes and nor’easters while the impact is reduced for mainland forests protected by barrier islands. Geographic position may account for differences in maritime forest resilience to disturbance. In this study, we quantify two geographically distinct maritime forests protected by dunes on Virginia’s Eastern Shore (i.e., mainland and barrier island) at two time points (15 and 21 years apart, respectively) to determine whether the trajectory is successional or presenting evidence of disassembly with sea-level rise and storm exposure. We hypothesize that due to position on the landscape, forest disassembly will be higher on the barrier island than mainland as evidenced by reduction in tree basal area and decreased species richness. Rate of relative sea-level rise in the region was 5.9 ± 0.7 mm yr−1 based on monthly mean sea-level data from 1975 to 2017. Savage Neck Dunes Natural Area Preserve maritime forest was surveyed using the point quarter method in 2003 and 2018. Parramore Island maritime forest was surveyed in 1997 using 32 m diameter circular plots. As the island has been eroding over the past two decades, 2016 Landsat imagery was used to identify remaining forested plots prior to resurveying. In 2018, only plots that remained forested were resurveyed. Lidar was used to quantify elevation of each point/plot surveyed in 2018. Plot elevation at Savage Neck was 1.93 ± 0.02 m above sea level, whereas at Parramore Island, elevation was lower at 1.04 ± 0.08 m. Mainland dominant species, Acer rubrum, Pinus taeda, and Liquidambar styraciflua, remained dominant over the study period, with a 14% reduction in the total number of individuals recorded. Basal area increased by 11%. Conversely, on Parramore Island, 33% of the former forested plots converted to grassland and 33% were lost to erosion and occur as ghost forest on the shore or were lost to the ocean. Of the remaining forested plots surveyed in 2018, dominance switched from Persea palustris and Juniperus virginiana to the shrub Morella cerifera. Only 46% of trees/shrubs remained and basal area was reduced by 84%. Shrub basal area accounted for 66% of the total recorded in 2018. There are alternative paths to maritime forest trajectory which differ for barrier island and mainland. Geographic position relative to disturbance and elevation likely explain the changes in forest community composition over the timeframes studied. Protected mainland forest at Savage Neck occurs at higher mean elevation and indicates natural succession to larger and fewer individuals, with little change in mixed hardwood-pine dominance. The fronting barrier island maritime forest on Parramore Island has undergone rapid change in 21 years, with complete loss of forested communities to ocean or conversion to mesic grassland. Of the forests remaining, dominant evergreen trees are now being replaced with the expanding evergreen shrub, Morella cerifera. Loss of biomass and basal area has been documented in other low elevation coastal forests. Our results indicate that an intermediate shrub state may precede complete loss of woody communities in some coastal communities, providing an alternative mechanism of resilience.

The Air Telang Protected Forest (ATPF) is one of the most dynamic and essential coastal forest landscapes in South Sumatra, Indonesia, because of its location between multiple river outlets, including the Musi catchment—Sumatra’s largest and most dense lowland catchment area. While most ATPF areas are covered by mangroves, these areas have been experiencing severe anthropogenic-driven degradation and conversion. This study aims to evaluate land cover changes and associated carbon emissions in the ATPF over a 35-year period (1985–2020) by utilizing the available Landsat and Sentinel imagery from 1985, 2000, and 2020. Throughout the analysis period, we observed 63% (from 10,886 to 4059 ha) primary and secondary forest loss due to land use change. We identified three primary anthropogenic activities driving these losses, namely, land clearing for plantations and agriculture (3693 ha), coconut plantations (3315 ha), aquaculture (245 ha). We estimated that the largest carbon emissions were caused by coconut plantation conversion, with total carbon emissions of approximately 14.14 Mt CO2-eq. These amounts were almost 4 and 21 times higher than emissions from land clearing and aquaculture, respectively, as substantial soil carbon loss occurs once mangroves get transformed into coconut plantations. While coconut plantation expansion on mangroves could generate significant carbon stock losses and cleared forests become the primary candidate for restoration, our dataset could be useful for future land-based emission reduction policy intervention at a subnational level. Ultimately, our findings have direct implications for current national climate policies, through low carbon development strategies and emission reductions from the land use sector for 2030, as outlined in the Nationally Determined Contributions (NDCs).

As a countermeasure against tsunami inundation, the present study conducted a series of laboratory experiments using a compound mitigation system in which a seaward embankment (E) followed by landward coastal vegetation (V) over a mound (M) (EMV) was investigated in supercritical flow conditions. The changes of flow around the mitigation system and energy reduction were clarified under varying conditions of mound height and vegetation density. Cases of an embankment followed by only a mound (EMNV) were also considered for comparison. Experimental results showed that three basic types of flow structures were observed within the mitigation system in EMV cases. A water cushion was created within the mitigation system mainly due to the combined effects of the mound and vegetation. It significantly reduced the maximum total energy in EMV cases by approximately 41–66%, whereas in EMNV cases, the maximum energy reduction was found to be 23–65%. Increments in both mound height and vegetation density increased the intensity of the water cushion within the mitigation system by offering more drag and reflecting the flow, and hence, significantly reduced the energy of the flow.

Malaysia has more than 800 islands that are rich in marine natural heritage, coastal landscapes and insular ecosystems. However, the biodiversity of flora and fauna on the terrestrial part of these islands has been given less attention and is rarely documented compared to those of underwater. Thus, this paper provides a brief note on the flora of Pulau Sibu, Johor as part of an effort to document the terrestrial biodiversity of the island. The botanical survey conducted during a scientific expedition in July 2017 recorded a total of 55 families with 110 species of plants in three vegetation types, where in some areas previously recorded as coconut plantation have become smaller and occupied by 'belukar' type of vegetation. One notable species on sandy mangrove is Mentinggi (Pemphis acidula). Although listed as 'Least Concern' by the IUCN, efforts should be taken to locally protect this species as over collection has been reported elsewhere in Malaysia. Floristic information gathered from this study will be useful for ecotourism development and enhancement of the terrestrial part of the island. [ABSTRACT FROM AUTHOR]

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The development of a method to easily investigate the spatial distribution of soil moisture and soil hardness in tree windbreaks is necessary because these windbreaks often decline due to inappropriate soil moisture condition and soil compaction. This research examined the applicability of ground-penetrating radar (GPR) and a combined penetrometer–moisture probe (CPMP) for evaluating the spatial distribution of soil moisture and soil hardness in four windbreaks with different soil characteristics. A GPR-reflecting interface was observed at a less permeable layer in a coastal windbreak and at a depth affected by soil compaction in an inland windbreak with andosol. The spatial distribution of the groundwater table could also be evaluated by examining the attenuation of GPR reflection in a coastal windbreak. In contrast, GPR was not applicable in an inland windbreak with peat because of high soil water content near the soil surface. The CPMP could detect vertical distributions of soil hardness and soil water content regardless of soil type. The CPMP was useful for interpreting GPR profiles, and GPR was useful for interpolating the information about the horizontal distribution of soil moisture and soil hardness between survey points made with the CPMP. Thus, the combination of GPR and a CPMP is ideal for examining the two-dimensional spatial distribution of soil moisture and soil hardness at windbreaks with soils for which both methods are applicable.

Abstract With the growing volume of research involving Thysanoptera in Brazil, studies were carried out to improve our understanding of the diversity of thrips in areas where the fauna has historically been neglected. Accordingly, we recorded the diversity of thrips (Insecta: Thysanoptera) associated with a restinga fragment located on the campus of the State University of Ceará (UECE), Fortaleza, Ceará state, and computed the estimated richness and diversity indices. Samples were collected from 2011 through 2013 from flowers of 86 plant species. The material was taken to the Laboratory of Insect-Plant Interaction, where thrips were screened under stereomicroscope. We collected 456 adults and 58 immatures, representing 14 species, in addition to one unidentified species of Treherniella. Microcephalothrips abdominalis was found on a large number of host plants, and Frankliniella insularis was the most common species. About two-thirds of the total richness of thrips species was associated with three plant families (Amaranthaceae, Caesalpiniaceae and Poaceae); six thrips species were each associated with only one plant species. The richness of the species collected was close to that estimated by Bootstrap and Jackknife 1 analysis. The Shannon-Wiener (H’) and Simpson (D) diversity indexes were 1,7607 and 0.7769, respectively. Although the species are common, 46 new associations between plant species and thrips were established, 13 of which are true host associations, which demonstrates the importance of coastal vegetation in maintaining populations of thrips.

Anthropogenic activities caused a severe loss of pristine habitats alongside with fragmentation of remaining habitats and the deterioration of habitat quality. The Arabuko Sokoke forest represents the largest remnant of East African coastal forest. Despite conservation efforts to maintain biodiversity in this forest, populations of several species are declining, including flagship species like the endemic Sokoke Scops Owl Otus ireneae. In this study, we assessed the presence of O. ireneae based on playback technique to identify the occurrence of this species across the forest. We then analysed habitat parameters at sites occupied and non-occupied by the owl species. Our data show that O. ireneae occurs restricted to one single forest type, the Cynometra woodland. Results obtained from parametric one-way ANOVA and structural equation modelling reveal that large old Cynometra webberi trees and dead wood are key requirements for the occurrence of this owl species. However, large C. webberi trees are currently illegally logged by the forest adjacent human population to produce timber, carvings, poles. Charcoal and dead wood represents a major energy source for households. Otus ireneae, being the smallest owl of East Africa may serve as a charismatic flag ship species to promote conservation of this endangered coastal forest, and furthermore as umbrella to conserve other forest species with similar habitat requirements. [ABSTRACT FROM AUTHOR]

In the present study, laboratory experiments were conducted to validate the applicability of a numerical model based on one-dimensional nonlinear long-wave equations. The model includes drag and inertia resistance of trees to tsunami flow and porosity between trees and a simplified forest in a wave channel. It was confirmed that the water surface elevation and flow velocity by the numerical simulations agree well with the experimental results for various forest conditions of width and tree density. Further, the numerical model was applied to prototype conditions of a coastal forest of Pandanus odoratissimus to investigate the effects of forest conditions (width and tree density) and incident tsunami conditions (period and height) on run-up height and potential tsunami force. The modeling results were represented in curve-fit equations with the aim of providing simplified formulae for designing coastal forest against tsunamis. The run-up height and potential tsunami forces calculated by the curve-fit formulae and the numerical model agreed within ± 10% error. [ABSTRACT FROM AUTHOR]

Sea level rise elicits short- and long-term changes in coastal plant communities by altering the physical conditions that affect ecosystem processes and species distributions. While the effects of sea level rise on salt marshes and mangroves are well studied, we focus on its effects on coastal islands of freshwater forest in Florida's Big Bend region, extending a dataset initiated in 1992. In 2014-2015, we evaluated tree survival, regeneration, and understory composition in 13 previously established plots located along a tidal creek; 10 plots are on forest islands surrounded by salt marsh, and three are in continuous forest. Earlier studies found that salt stress from increased tidal flooding prevented tree regeneration in frequently flooded forest islands. Between 1992 and 2014, tidal flooding of forest islands increased by 22%-117%, corresponding with declines in tree species richness, regeneration, and survival of the dominant tree species, Sabal palmetto (cabbage palm) and Juniperus virginiana (southern red cedar). Rates of S. palmetto and J. virginiana mortality increased nonlinearly over time on the six most frequently flooded islands, while salt marsh herbs and shrubs replaced forest understory vegetation along a tidal flooding gradient. Frequencies of tidal flooding, rates of tree mortality, and understory composition in continuous forest stands remained relatively stable, but tree regeneration substantially declined. Long-term trends identified in this study demonstrate the effect of sea level rise on spatial and temporal community reassembly trajectories that are dynamically re-shaping the unique coastal landscape of the Big Bend. [ABSTRACT FROM AUTHOR]