Land cover changes significantly affect mangrove forests,driven by both anthropogenic activities and natural processes.The Banlaem mangrove in Nakhon Si Thammarat,Thailand,supports numerous mangrove plantation project...Land cover changes significantly affect mangrove forests,driven by both anthropogenic activities and natural processes.The Banlaem mangrove in Nakhon Si Thammarat,Thailand,supports numerous mangrove plantation projects but lacks comprehensive assessments and monitoring related to land cover changes.This study aimed to(1)investigate land cover changes in the Banlaem mangrove from 1995 to 2023,and(2)generate a predictive model for future land cover changes.For land cover assessment,satellite imagery from multiple sources,including Sentinel-2(Level 2A)and Landsat(Collection 2 Level 2),was utilized to examine and classify changes in mangrove cover within the Banlaem mangrove forest from 1995 to 2023,using supervised classification with the maximum likelihood algorithm.Various regression models were analysed to develop a predictive model based on area size and time.The mangrove area in the Banlaem mangrove forest steadily grew throughout the study period,with the total area increasing from 56.16 ha in 1995 to 527.55 ha in 2023.This study represents the first analysis of changes in the Banlaem mangrove cover.Throughout the tested models,they reveal an unclear pattern of mangrove expansion,yet they indicate a high rate of expansion in the Banlaem mangrove forest.In addition,these results are expected to encourage greater community involvement in the monitoring and management of the Banlaem mangrove.We recommend establishing a community monitoring network to engage local residents in tracking changes in mangrove cover,supported by training and resources.展开更多
The contamination and accumulation of microplastics(MPs)in mangrove ecosystems have become an increasing concern due to their potential ecological risks.This study investigated and analyzed the abundance of MPs in sed...The contamination and accumulation of microplastics(MPs)in mangrove ecosystems have become an increasing concern due to their potential ecological risks.This study investigated and analyzed the abundance of MPs in sediments,water,and benthos of mangrove areas(MA)and adjacent non-vegetated areas(NA)in Qinglan Bay.Results showed that the abundance of MPs in MA was significantly higher than in adjacent NA[sediment:(4.39±2.20)items/50 g dry weight(dw)vs.(4.10±2.71)items/50 g dw;water:(11.79±7.61)items/L vs.(10.61±5.93)items/L;benthos:(4.94±5.27)items/individual vs.(3.5±0.71)items/individual].The primary components identified in sediments and benthos were rayon and cellulose,while polyethylene(PE)and polypropylene(PP)dominated in water.Smaller MPs(<1000μm)accounted for 44%,43%,and 61%of the MPs in sediments,water,and benthos,respectively,indicating that smaller MPs are more likely to be ingested or captured by benthic organisms.Additionally,MPsenrichment was calculated in benthos[enrichment index(EI)=1.41],water(EI=1.11),and sediments(EI=1.09),confirming that the unique ecological environment of the MA leads to different distribution and accumulation characteristics of MPs compared to the NA.The ecological risk assessment revealed low MPs pollution levels in sediments and water,but higher risks were observed for polychaetes and bivalves.展开更多
Mangrove ecosystems along Vietnam’s coastline face significant degradation due to human activities,despite their crucial role in coastal protection against natural hazards.This study aims to assess the spatial and te...Mangrove ecosystems along Vietnam’s coastline face significant degradation due to human activities,despite their crucial role in coastal protection against natural hazards.This study aims to assess the spatial and temporal changes in mangrove coverage along Vietnam’s southern coast by integrating remote sensing techniques with hydrodynamic model simulations.The research methodology combines the Collect Earth tool analysis of Spot-4 and Planet satellite imagery(2000–2020)with Mike 21-HD two-dimensional(2D)hydrodynamic modeling to evaluate mangrove coverage changes by simulating shoreline erosion.Results analysis reveals that a significant increase of 109.83 ha in mangrove area within Vinh Chau Town of Soc Trang Province during the period 2010–2020,predominantly in the eastern region.Hydrodynamic simulations demonstrate that the coastal zone is primarily influenced by the interaction of nearshore currents,East Sea tides,and seasonal monsoon wave patterns.The model results effectively capture the complex interactions between these hydrodynamic factors and mangrove distribution.These findings not only validate the effectiveness of combining remote sensing and hydrodynamic modeling for mangrove assessment but also provide crucial insights for sustainable coastal ecosystem management.The study’s integrated approach offers a robust framework for monitoring mangrove dynamics and developing evidence-based conservation strategies,highlighting the importance of maintaining these vital ecosystems for coastal protection.展开更多
Remote sensing and web-based platforms have emerged as vital tools in the effective monitoring of mangrove ecosystems, which are crucial for coastal protection, biodiversity, and carbon sequestration. Utilizing satell...Remote sensing and web-based platforms have emerged as vital tools in the effective monitoring of mangrove ecosystems, which are crucial for coastal protection, biodiversity, and carbon sequestration. Utilizing satellite imagery and aerial data, remote sensing allows researchers to assess the health and extent of mangrove forests over large areas and time periods, providing insights into changes due to environmental stressors like climate change, urbanization, and deforestation. Coupled with web-based platforms, this technology facilitates real-time data sharing and collaborative research efforts among scientists, policymakers, and conservationists. Thus, there is a need to grow this research interest among experts working in this kind of ecosystem. The aim of this paper is to provide a comprehensive literature review on the effective role of remote sensing and web-based platform in monitoring mangrove ecosystem. The research paper utilized the thematic approach to extract specific information to use in the discussion which helped realize the efficiency of digital monitoring for the environment. Web-based platforms and remote sensing represent a powerful tool for environmental monitoring, particularly in the context of forest ecosystems. They facilitate the accessibility of vital data, promote collaboration among stakeholders, support evidence-based policymaking, and engage communities in conservation efforts. As experts confront the urgent challenges posed by climate change and environmental degradation, leveraging technology through web-based platforms is essential for fostering a sustainable future for the forests of the world.展开更多
Mangrove ecosystems support biodiversity,protect coastal areas,and provide sustainable livelihoods.However,they face significant threats from deforestation and unsustainable land use practices.This study examines the ...Mangrove ecosystems support biodiversity,protect coastal areas,and provide sustainable livelihoods.However,they face significant threats from deforestation and unsustainable land use practices.This study examines the viability of the payments for ecosystem services(PES)programs in promoting sustainable mangrove tourism in Tongke-Tongke Village,Sinjai District,South SulawesiProvince,Indonesia.We collected data through household surveys,semi-structured stakeholder interviews,and tourist questionnaires to evaluate the economic value of mangrove tourism and tourists’willingness to pay(WTP)for conservation.Analytical methods included quantitative descriptive analysis,thematic analysis,travel cost analysis,and contingent valuationmethod.The results indicatedstrong community support,with 70.00% of respondents acknowledging sustainable mangrove tourism’s economic,environmental,and cultural benefits.Economic estimates revealedthat mangrove tourism generated 943.00 USD/(hm^(2)·a),while tourists’WTP for conservation rangedfrom 0.21 to 0.56 USD/(person×month),contributing approximately 11.39 USD/(hm^(2)·a).Despite challenges such as inadequate infrastructure,socioeconomic disparities,and land privatization,this study advocates for integrating the PES programs,enhancing governance frameworks,and fostering local community engagement to ensure equitable benefit distribution and maximize the potential of mangrove tourism.These strategies aim to bolster conservation efforts,improve local livelihoods,and strengthen the resilience of mangroveecosystems.展开更多
Bangladesh is a deltaic country with a 710 km coastline and numerous newly accreted offshore islands in the central and eastern coastal regions. Natural mangrove forest (the Sundarbans) occupies about 100 km of coastl...Bangladesh is a deltaic country with a 710 km coastline and numerous newly accreted offshore islands in the central and eastern coastal regions. Natural mangrove forest (the Sundarbans) occupies about 100 km of coastline in the southwest, which protects the lives and properties of the coastal population of that area. The depletion of the forest stock of the Sundarbans was reported in 1875 due to the large-scale clearings by the woodcutters and uncertainty in natural regeneration. The restoration of the Sundarbans in the name of enrichment plantation and assisted natural regeneration was formally introduced in 1959 with Excoecaria agallocha followed by the introduction of mangrove and mainland (non-mangrove) species in the moderate to high saline zone and raised lands in the freshwater zone, respectively in 1975. Chakaria Sundarbans, the second largest natural mangrove forest on the east coast, was highly degraded with the rapid expansion of aquaculture between 1976 and 1989. Tremendous human interferences significantly altered the site condition, interrupting natural recovery. Coastal afforestation was initiated in 1966 with two pioneer mangrove species (Sonneratia apetala and Avicennia officinalis). Some afforested sites require attention for restoration due to natural and manmade causes. Bangladesh Forest Department adopted restoration activities with the technical support of the Bangladesh Forest Research Institute and other agencies. However, all the restoration activities for the Sundarbans, Chakaria Sundarbans, and coastal afforested sites had some success and failure stories. The success and failure of a mangrove restoration activity depends on planning (active or passive restoration), selection of suitable sites and species, planting materials, local community involvement, monitoring, evaluation and plantation management.展开更多
Mangrove forest is always considered an effective barrier to protect habitats from high waves,especially tsunami.Therefore,the estimation of wave energy dissipation is required for disater warning.The aim of this stud...Mangrove forest is always considered an effective barrier to protect habitats from high waves,especially tsunami.Therefore,the estimation of wave energy dissipation is required for disater warning.The aim of this study is to calculate wave attenuation in mangrove areas by combining field survey method and mathematical modeling method.The application area is Cu Lao Dung mangrove forest,Soc Trang,Vietnam.From data measurements of hydrodynamics and mangrove characteristics,the wave attenuation coefficient r,the drag coefficient Cd were determined in mud area,mud-mangrove area and mangrove area.In addition,using WAPROMAN model,the attenuation of wave height is simulated in different cases such as without mangrove,with mangrove,breaking wave effect and wave trunk interaction effect.Both the results from the measured method and the model method show the role of mangroves in reducing wave energy.The results from modeling are smaller than the calculated results.However,both methods tend to be suitable.Such difference required more considerations not only on calculation formulas but also on modeling adjustment.The research clearly demonstrated the effectiveness of mangroves in coastal protection,with wave-trunk interaction becoming the dominant factor in energy dissipation deeper into the forest.For future,extending the study to different mangrove forests and longer time scales could provide a more comprehensive understanding of the role of mangroves in coastal protection across various geographical and temporal contexts.展开更多
This research investigates the ecological importance,changes,and status of mangrove wetlands along China’s coastline.Visual interpretation,geological surveys,and ISO clustering unsupervised classification methods are...This research investigates the ecological importance,changes,and status of mangrove wetlands along China’s coastline.Visual interpretation,geological surveys,and ISO clustering unsupervised classification methods are employed to interpret mangrove distribution from remote sensing images from 2021,utilizing ArcGIS software platform.Furthermore,the carbon storage capacity of mangrove wetlands is quantified using the carbon storage module of InVEST model.Results show that the mangrove wetlands in China covered an area of 278.85 km2 in 2021,predominantly distributed in Hainan,Guangxi,Guangdong,Fujian,Zhejiang,Taiwan,Hong Kong,and Macao.The total carbon storage is assessed at 2.11×10^(6) t,with specific regional data provided.Trends since the 1950s reveal periods of increase,decrease,sharp decrease,and slight-steady increases in mangrove areas in China.An important finding is the predominant replacement of natural coastlines adjacent to mangrove wetlands by artificial ones,highlighting the need for creating suitable spaces for mangrove restoration.This study is poised to guide future mangroverelated investigations and conservation strategies.展开更多
Mangroves play a pivotal role in tropical and subtropical coastal ecosystem,yet they are highly vulnerable to the effects of climate change,particularly the accelerated global sea level rise(SLR)and stronger tropical ...Mangroves play a pivotal role in tropical and subtropical coastal ecosystem,yet they are highly vulnerable to the effects of climate change,particularly the accelerated global sea level rise(SLR)and stronger tropical cyclones(TCs).However,there is a lack of research addressing future simultaneous combined impacts of the slow-onset of SLR and rapid-onset of TCs on China's mangroves.In order to develop a comprehensive risk assessment method considering the superimposed effects of these two factors and analyze risk for mangroves in Dongzhaigang,Hainan Island,China,we used observational and climate model data to assess the risks to mangroves under low,intermediate,and very high greenhouse gas(GHG)emission scenarios(such as SSP1-2.6,SSP2-4.5,and SSP5-8.5)in 2030,2050,and 2100,and compiled a risk assessment scheme for mangroves in Dongzhaigang,China.The results showed that the combined risks from SLR and TCs will continue to rise;however,SLRs will increase in intensity,and TCs will decrease.The comprehensive risk of the Dongzhaigang mangroves posed by climate change will remain low under SSP1-2.6 and SSP2-4.5 scenarios by 2030,but it will increase substantially by 2100.While under SSP5-8.5 scenario,the risks to mangroves in Dongzhaigang are projected to increase considerably by 2050,and approximately 68.8%of mangroves will be at very high risk by 2100.The risk to the Dongzhaigang mangroves is not only influenced by the hazards but also closely linked to their exposure and vulnerability.We therefore propose climate resilience developmental responses for mangroves to address the effects of climate change.This study for the combined impact of TCs and SLR on mangroves in Dongzhaigang,China can enrich the method system of mangrove risk assessment and provide references for scientific management.展开更多
Mangrove ecosystems have important ecological and economic values,especially their ability to store carbon.However,in recent years,human disturbance has accelerated mangrove degradation.Among them,the emission of poll...Mangrove ecosystems have important ecological and economic values,especially their ability to store carbon.However,in recent years,human disturbance has accelerated mangrove degradation.Among them,the emission of pollutants cannot be ignored.It is of great significance for carbon emission reduction and ecological protection to study the impacts of different pollutants on mangroves and their carbon stocks.Based on the remote sensing data of coastal areas south of the Yangtze River in China's Mainland,this paper builds the ensemble learning model Random Forest(RF)and Gradient Boosting Regression(GBR)to empirically analyse the relationship between industrial wastewater,industrial sulfur dioxide(SO2),PM2.5 and mangrove forests.The results show that the pollutant concentration of meteorological normalisation is more stable.The importance of pollutants presents regional heterogeneity.The area of mangroves in different cities and the corresponding total carbon stocks show different trends with the increase or decrease of pollutants,and there is a dynamic balance between urban pollutant discharge and mangrove growth in some cities.The research in this paper provides an analysis and explanation from the perspective of machine learning to explore the relationship between mangroves and pollutants and at the same time,provides scientific suggestions for the formulation of future pollutant emission policies in different cities.展开更多
Mangrove wetlands are among the four most productive tropical and subtropical ecosystems.They are also a core component of the coastal blue carbon ecosystem,which is of great ecological significance to human beings,pl...Mangrove wetlands are among the four most productive tropical and subtropical ecosystems.They are also a core component of the coastal blue carbon ecosystem,which is of great ecological significance to human beings,plants,animals,and the global carbon balance.There has been a global decrease in the distribution of mangrove forests,and their ecological function has gradually degenerated since the Holocene.Sediment from coastal mangrove wetlands can provide records of climate change and human activities,and multiple proxies including palynology,leaf fossil,biomarkers,DNA,phytolith and stable isotopes,can be used to reconstruct the evolutionary stages of paleo-mangroves and to identify the effect of natural processes and human activities on the distribution and evolution of mangroves.This information can provide theoretical support for mangrove protection and for improving carbon sequestration capacity.This paper summarizes and compares the multiple proxies for mangrove reconstruction,reviews progress in the study of natural succession of global mangroves since the Holocene,expands on the influence mechanisms of human activities on mangrove growth and development and uses past information to lay a foundation for a model to predict future mangrove development.展开更多
Salinity is among the most critical factors limiting the growth and species distribution of coastal plants.Water salinity in estuarine ecosystems varies temporally and spatially,but the variation patterns across diffe...Salinity is among the most critical factors limiting the growth and species distribution of coastal plants.Water salinity in estuarine ecosystems varies temporally and spatially,but the variation patterns across different time scales and salinity fluctuation have rarely been quantified.The effects of salinity on floristic diversity in mangroves are not fully understood due to the temporal and spatial heterogeneity of salinity.In this study,we monitored water salinity at an interval of 10-min over one year in three mangrove catchment areas representing the outer part,middle part,and inner part respectively of Dongzhai Bay,Hainan,China.The number of mangrove community types and dominant mangrove species of the three catchment areas were also investigated.We found that the diurnal variation and dry-season intra-month variation in water salinity were driven by tidal cycles.The seasonal variation in water salinity was mainly driven by rainfall with higher salinity occurring in the dry season and lower salinity occurring in the wet season.Spatially,water salinity was highest at the outer part,intermediate at the middle part,and lowest at the inner part of the bay.The intra-month and annual fluctuations of water salinity were highest at the middle part and lowest at the outer part of the bay.The number of mangrove community types and dominant species were lowest at the outer part,intermediate at the middle part,and highest at the inner part of the bay.These results suggest that the temporal variation of water salinity in mangroves is driven by different factors at different time scales and therefore it is necessary to measure water salinity at different time scales to get a complete picture of the saline environment that mangroves experience.Spatially,lower salinity levels benefit mangrove species richness within a bay landscape,however,further research is needed to distinguish the effects of salinity fluctuation and salinity level in affecting mangrove species richness.展开更多
This paper reviews and discusses the technical terms and definition of mangrove and mangal, as well as mangrove plant. The word mangrove has been used to refer either to the constituent plant of tropical and subtropic...This paper reviews and discusses the technical terms and definition of mangrove and mangal, as well as mangrove plant. The word mangrove has been used to refer either to the constituent plant of tropical and subtropical intertidal community or to the community itself, but this usage makes more confusion. Being leaved mangrove in the more limited sense for the constituent plant species, mangal was proposed by MacNae (1968) as a term for mangrove community, which has been universally applied to most previous studies and should be adopted now. Mangrove should be therefore defined as a tropical and subtropical tree restricted to intertidal zones, which possesses some morphological specializion and physiological mechanism adapted to its habitat, and mangal as a tropical and subtropical forest community restricted to marine intertidal zones and periodically inundeated by the tides. A new term "consortive plant" is proposed here for herb, liana, epiphyte or parasite, which is restricted in the strict mangrove habitat.展开更多
Mangrove forests in southern Iran are of high ecological and economic importance.These forests are being threatened because of uncontrolled harvesting to provide fodder for livestock.The objective of this study is to ...Mangrove forests in southern Iran are of high ecological and economic importance.These forests are being threatened because of uncontrolled harvesting to provide fodder for livestock.The objective of this study is to provide recommendations for appropriate harvesting intensities by quantifying the effect of different harvesting intensities on vegetative and vigor characteristics of mangrove trees.This study was conducted using a randomized complete block design comprising four treatments(10.00%,20.00%,and 30.00% trimming,along with a control)replicated three times.Vegetative characteristics were measured before and after trimming(five-year period)and analyzed using generalized linear model statistical analysis.The growths of the average diameter of canopy,canopy area,canopy volume,canopy height,tree height,and collar diameter in the control treatment were all significantly higher than those in the trimming treatments.In addition,there was a decreasing trend in leaf fresh and dry mass,leaf area index,total area of canopy leaves,and health status of tree in the trimming treatments.For example,the percentage change in fresh and dry leaf mass in the control treatment was positive(29.87% and 38.31%,respectively),whereas the trimming treatments of 10.00%,20.00% and 30.00% had negative effects(-7.01% and -4.79%,-11.32% and -14.30%,and -15.84% and -17.29%,respectively).In addition,the changes in leaf area index in the control(4.95%)and 30.00% trimming(-24.57%)treatments were the highest and lowest,respectively.The percentage change in soil organic matter in the control,10.00%,20.00%,and 30.00% treatments were 22.94%,-9.90%,-16.91%,and -18.68%,respectively.The study demonstrated that gray mangrove trees were highly sensitive to canopy trimming,with even minimal trimming intensities negatively affecting vegetative growth and soil organic matter.Therefore,it is recommended that cutting and trimming of mangrove trees should be prevented even at low intensity to preserve mangrove ecosystem health and resilience against environmental stressors.展开更多
This paper provides a comprehensive overview on coastal protection and hazard mitigation by mangroves.Previous stud-ies have made great strides to understand the mechanisms and influencing factors of mangroves’protec...This paper provides a comprehensive overview on coastal protection and hazard mitigation by mangroves.Previous stud-ies have made great strides to understand the mechanisms and influencing factors of mangroves’protection function,including wave energy dissipation,storm surge damping,tsunami mitigation,adjustment to sea level rise and wind speed reduction,which are sys-tematically summarized in this study.Moreover,the study analyzes the extensive physical models,based on indoor flume experi-ments and numerical models,that consider the interaction between mangroves and hydrodynamics,to help our understanding of mangrove-hydrodynamic interactions.Additionally,quantitative approaches for valuing coastal protection services provided by man-groves,including index-based and process-resolving approaches,are introduced in detail.Finally,we point out the limitations of previous studies,indicating that efforts are still required for obtaining more long-term field observations during extreme weather events,to create more real mangrove models for physical experiments,and to develop numerical models that consider the flexible properties of mangroves to better predict wave propagation in mangroves having complex morphology and structures.展开更多
Mangroves are indispensable to coastlines,maintaining biodiversity,and mitigating climate change.Therefore,improving the accuracy of mangrove information identification is crucial for their ecological protection.Aimin...Mangroves are indispensable to coastlines,maintaining biodiversity,and mitigating climate change.Therefore,improving the accuracy of mangrove information identification is crucial for their ecological protection.Aiming at the limited morphological information of synthetic aperture radar(SAR)images,which is greatly interfered by noise,and the susceptibility of optical images to weather and lighting conditions,this paper proposes a pixel-level weighted fusion method for SAR and optical images.Image fusion enhanced the target features and made mangrove monitoring more comprehensive and accurate.To address the problem of high similarity between mangrove forests and other forests,this paper is based on the U-Net convolutional neural network,and an attention mechanism is added in the feature extraction stage to make the model pay more attention to the mangrove vegetation area in the image.In order to accelerate the convergence and normalize the input,batch normalization(BN)layer and Dropout layer are added after each convolutional layer.Since mangroves are a minority class in the image,an improved cross-entropy loss function is introduced in this paper to improve the model’s ability to recognize mangroves.The AttU-Net model for mangrove recognition in high similarity environments is thus constructed based on the fused images.Through comparison experiments,the overall accuracy of the improved U-Net model trained from the fused images to recognize the predicted regions is significantly improved.Based on the fused images,the recognition results of the AttU-Net model proposed in this paper are compared with its benchmark model,U-Net,and the Dense-Net,Res-Net,and Seg-Net methods.The AttU-Net model captured mangroves’complex structures and textural features in images more effectively.The average OA,F1-score,and Kappa coefficient in the four tested regions were 94.406%,90.006%,and 84.045%,which were significantly higher than several other methods.This method can provide some technical support for the monitoring and protection of mangrove ecosystems.展开更多
Since the 1980s,the robust economic growth of China has prompted extensive land reclamation projects along its coastline,notably affecting local hydrodynamics and resulting in ecological repercussions.Using a nearshor...Since the 1980s,the robust economic growth of China has prompted extensive land reclamation projects along its coastline,notably affecting local hydrodynamics and resulting in ecological repercussions.Using a nearshore finite volume ocean model,we constructed a hydrodynamic model for Shacheng Bay,a southeastern coastal region with a winding and narrow entrance.We examined the hydrodynamic changes and mangrove dynamics over the past 36 years and the relationship between hydrodynamic alterations and mangrove degradation.Simulation results reveal that extensive reclamation projects between 1984 and 2000 weakened the current in Shacheng Bay,leading to decreased water exchange capacity and a significant reduction in mangrove area from 0.3 to 0.06km^(2).During this period,over 37% of mangrove degradation was ascribed to time-changing hydrodynamic variables without the direct influence of land reclamation.The results also highlight the changes in local hydrodynamics and water exchange patterns that adversely influenced mangrove growth.From 2000 to 2020,there were minimal coastline changes in Shacheng Bay,demonstrating reduced land reclamation activities.This stopped the further weakening trend of the currents,with a slight increase during ebb tides,while the residual current continued to weaken due to the decreasing tidal prism and water exchange capacity.The mangrove area partially recovered during this period,expanding from 0.06 to 0.11 km^(2),predominantly in new areas instead of where mangroves disappeared from 1984 to 2000.This work underlines the intricate relationship between land reclamation,hydrodynamics,and mangrove ecosystems,underscoring the need for sustainable coastal development strategies.展开更多
(±)-Mycosphatide A(1a/1b),a pair of highly oxidized enantiomeric polyketides featuring a unique5/5/6/5-fused tetracyclic ring system,were isolated from the mangrove endophytic fungus Mycosphaerella sp.SYSU-DZG01....(±)-Mycosphatide A(1a/1b),a pair of highly oxidized enantiomeric polyketides featuring a unique5/5/6/5-fused tetracyclic ring system,were isolated from the mangrove endophytic fungus Mycosphaerella sp.SYSU-DZG01.Their structures were established by extensive spectroscopic analyses,single crystal Xray diffraction,and experimental electronic circular dichroism(ECD)spectra comparison.The plausible biosynthetic pathway of 1 was proposed,which involved the generation of a key spiro[4.5]decane scaffold.Compounds(+)-1a and(-)-1b exhibited significant lipid-lowering activity in 3T3-L1 adipocytes model,with EC50values of 7.85±1.56 and 8.87±0.80μmol/L,respectively.展开更多
Global carbon cycle has received extensive attention,among which the river-estuary system is one of the important links connecting the carbon cycle between land and ocean.In this paper,the distribution and control fac...Global carbon cycle has received extensive attention,among which the river-estuary system is one of the important links connecting the carbon cycle between land and ocean.In this paper,the distribution and control factors of particulate organic carbon(POC)were studied by using the data of organic carbon contents and its carbon isotopic composition(δ13C)in the mainstream and estuary of Passur River in the Sundarbans area,combined with the hydrological and biological data measured by CTD.The results show that POC content ranged from 0.263 mg/L to 9.292 mg/L,and the POC content in the river section(averaged 4.129 mg/L)was significantly higher than that in the estuary area(averaged 0.858 mg/L).Two distinct stages of POC transport from land to sea in the Sundarbans area were identified.The first stage occurred in the river section,where POC distribution was mainly controlled by the dynamic process of runoff and the organic carbon was mainly terrestrial source.The second stage occurred during estuarine mixing,where the POC distribution was mainly controlled by the mixing process of seawater and freshwater.The source of POC was predominantly marine and exhibiting vertical differences.The surface and middle layers were primarily influenced by marine sources,while the bottom layer was jointly controlled by terrestrial and marine sources of organic carbon.These findings are of great significance for understanding the carbon cycle in such a large mangrove ecosystem like the Sundarbans mangrove.展开更多
Seven novel linear polyketides,talaketides A-G(1-7),were isolated from the rice media cultures of the mangrove sed-iment-derived fungus Talaromyces sp.SCSIO 41027.Among these,talaketides A-E(1-5)represented unpreceden...Seven novel linear polyketides,talaketides A-G(1-7),were isolated from the rice media cultures of the mangrove sed-iment-derived fungus Talaromyces sp.SCSIO 41027.Among these,talaketides A-E(1-5)represented unprecedented unsaturated lin-ear polyketides with an epoxy ring structure.The structures,including absolute configurations of these compounds,were elucidated through detailed analyses of nuclear magnetic resonance(NMR)and high-resolution mass spectrometry(HR-MS)data,as well as elec-tronic custom distributors(ECD)calculations.In the cytotoxicity screening against prostate cancer cell lines,talaketide E(5)demon-strated a dose-dependent inhibitory effect on prostate cancer PC-3 cell lines,with an IC50 value of 14.44 μmol·L-1.Moreover,com-pound 5 significantly inhibited the cloning formation of PC-3 cell lines and arrested the cell cycle in S-phase,ultimately inducing ap-optosis.These findings indicate that compound 5 may serve as a promising lead compound for the development of a potential treat-ment for prostate cancer.展开更多
文摘Land cover changes significantly affect mangrove forests,driven by both anthropogenic activities and natural processes.The Banlaem mangrove in Nakhon Si Thammarat,Thailand,supports numerous mangrove plantation projects but lacks comprehensive assessments and monitoring related to land cover changes.This study aimed to(1)investigate land cover changes in the Banlaem mangrove from 1995 to 2023,and(2)generate a predictive model for future land cover changes.For land cover assessment,satellite imagery from multiple sources,including Sentinel-2(Level 2A)and Landsat(Collection 2 Level 2),was utilized to examine and classify changes in mangrove cover within the Banlaem mangrove forest from 1995 to 2023,using supervised classification with the maximum likelihood algorithm.Various regression models were analysed to develop a predictive model based on area size and time.The mangrove area in the Banlaem mangrove forest steadily grew throughout the study period,with the total area increasing from 56.16 ha in 1995 to 527.55 ha in 2023.This study represents the first analysis of changes in the Banlaem mangrove cover.Throughout the tested models,they reveal an unclear pattern of mangrove expansion,yet they indicate a high rate of expansion in the Banlaem mangrove forest.In addition,these results are expected to encourage greater community involvement in the monitoring and management of the Banlaem mangrove.We recommend establishing a community monitoring network to engage local residents in tracking changes in mangrove cover,supported by training and resources.
基金The Natural Science Foundation of China under contract Nos 41806130 and 42407149the National Science Foundation for Post-doctoral Scientists of China under contract No.2024M750629+2 种基金the Natural Science Foundation of Guangdong Province under contract No.2018A0303130063the Marine Ecological Survey and Evaluation in Guangdong Province under contract No.0877-23GZTP01F179the Project of the Marine Geological Survey Program of China Geological Survey under contract Nos DD20230460,DD20242792,DD20211394,and DD20190308.
文摘The contamination and accumulation of microplastics(MPs)in mangrove ecosystems have become an increasing concern due to their potential ecological risks.This study investigated and analyzed the abundance of MPs in sediments,water,and benthos of mangrove areas(MA)and adjacent non-vegetated areas(NA)in Qinglan Bay.Results showed that the abundance of MPs in MA was significantly higher than in adjacent NA[sediment:(4.39±2.20)items/50 g dry weight(dw)vs.(4.10±2.71)items/50 g dw;water:(11.79±7.61)items/L vs.(10.61±5.93)items/L;benthos:(4.94±5.27)items/individual vs.(3.5±0.71)items/individual].The primary components identified in sediments and benthos were rayon and cellulose,while polyethylene(PE)and polypropylene(PP)dominated in water.Smaller MPs(<1000μm)accounted for 44%,43%,and 61%of the MPs in sediments,water,and benthos,respectively,indicating that smaller MPs are more likely to be ingested or captured by benthic organisms.Additionally,MPsenrichment was calculated in benthos[enrichment index(EI)=1.41],water(EI=1.11),and sediments(EI=1.09),confirming that the unique ecological environment of the MA leads to different distribution and accumulation characteristics of MPs compared to the NA.The ecological risk assessment revealed low MPs pollution levels in sediments and water,but higher risks were observed for polychaetes and bivalves.
基金supported by Environmental Protection Project 2023-2024,with the Joint Vietnam-Russia Tropical Science and Technology Research Center(Southern Branch)as the lead Institution.
文摘Mangrove ecosystems along Vietnam’s coastline face significant degradation due to human activities,despite their crucial role in coastal protection against natural hazards.This study aims to assess the spatial and temporal changes in mangrove coverage along Vietnam’s southern coast by integrating remote sensing techniques with hydrodynamic model simulations.The research methodology combines the Collect Earth tool analysis of Spot-4 and Planet satellite imagery(2000–2020)with Mike 21-HD two-dimensional(2D)hydrodynamic modeling to evaluate mangrove coverage changes by simulating shoreline erosion.Results analysis reveals that a significant increase of 109.83 ha in mangrove area within Vinh Chau Town of Soc Trang Province during the period 2010–2020,predominantly in the eastern region.Hydrodynamic simulations demonstrate that the coastal zone is primarily influenced by the interaction of nearshore currents,East Sea tides,and seasonal monsoon wave patterns.The model results effectively capture the complex interactions between these hydrodynamic factors and mangrove distribution.These findings not only validate the effectiveness of combining remote sensing and hydrodynamic modeling for mangrove assessment but also provide crucial insights for sustainable coastal ecosystem management.The study’s integrated approach offers a robust framework for monitoring mangrove dynamics and developing evidence-based conservation strategies,highlighting the importance of maintaining these vital ecosystems for coastal protection.
文摘Remote sensing and web-based platforms have emerged as vital tools in the effective monitoring of mangrove ecosystems, which are crucial for coastal protection, biodiversity, and carbon sequestration. Utilizing satellite imagery and aerial data, remote sensing allows researchers to assess the health and extent of mangrove forests over large areas and time periods, providing insights into changes due to environmental stressors like climate change, urbanization, and deforestation. Coupled with web-based platforms, this technology facilitates real-time data sharing and collaborative research efforts among scientists, policymakers, and conservationists. Thus, there is a need to grow this research interest among experts working in this kind of ecosystem. The aim of this paper is to provide a comprehensive literature review on the effective role of remote sensing and web-based platform in monitoring mangrove ecosystem. The research paper utilized the thematic approach to extract specific information to use in the discussion which helped realize the efficiency of digital monitoring for the environment. Web-based platforms and remote sensing represent a powerful tool for environmental monitoring, particularly in the context of forest ecosystems. They facilitate the accessibility of vital data, promote collaboration among stakeholders, support evidence-based policymaking, and engage communities in conservation efforts. As experts confront the urgent challenges posed by climate change and environmental degradation, leveraging technology through web-based platforms is essential for fostering a sustainable future for the forests of the world.
基金the State University of Makassar for their financial backing of this study(SP DIPA-023.17.2.677523/2021 Revision 01).
文摘Mangrove ecosystems support biodiversity,protect coastal areas,and provide sustainable livelihoods.However,they face significant threats from deforestation and unsustainable land use practices.This study examines the viability of the payments for ecosystem services(PES)programs in promoting sustainable mangrove tourism in Tongke-Tongke Village,Sinjai District,South SulawesiProvince,Indonesia.We collected data through household surveys,semi-structured stakeholder interviews,and tourist questionnaires to evaluate the economic value of mangrove tourism and tourists’willingness to pay(WTP)for conservation.Analytical methods included quantitative descriptive analysis,thematic analysis,travel cost analysis,and contingent valuationmethod.The results indicatedstrong community support,with 70.00% of respondents acknowledging sustainable mangrove tourism’s economic,environmental,and cultural benefits.Economic estimates revealedthat mangrove tourism generated 943.00 USD/(hm^(2)·a),while tourists’WTP for conservation rangedfrom 0.21 to 0.56 USD/(person×month),contributing approximately 11.39 USD/(hm^(2)·a).Despite challenges such as inadequate infrastructure,socioeconomic disparities,and land privatization,this study advocates for integrating the PES programs,enhancing governance frameworks,and fostering local community engagement to ensure equitable benefit distribution and maximize the potential of mangrove tourism.These strategies aim to bolster conservation efforts,improve local livelihoods,and strengthen the resilience of mangroveecosystems.
文摘Bangladesh is a deltaic country with a 710 km coastline and numerous newly accreted offshore islands in the central and eastern coastal regions. Natural mangrove forest (the Sundarbans) occupies about 100 km of coastline in the southwest, which protects the lives and properties of the coastal population of that area. The depletion of the forest stock of the Sundarbans was reported in 1875 due to the large-scale clearings by the woodcutters and uncertainty in natural regeneration. The restoration of the Sundarbans in the name of enrichment plantation and assisted natural regeneration was formally introduced in 1959 with Excoecaria agallocha followed by the introduction of mangrove and mainland (non-mangrove) species in the moderate to high saline zone and raised lands in the freshwater zone, respectively in 1975. Chakaria Sundarbans, the second largest natural mangrove forest on the east coast, was highly degraded with the rapid expansion of aquaculture between 1976 and 1989. Tremendous human interferences significantly altered the site condition, interrupting natural recovery. Coastal afforestation was initiated in 1966 with two pioneer mangrove species (Sonneratia apetala and Avicennia officinalis). Some afforested sites require attention for restoration due to natural and manmade causes. Bangladesh Forest Department adopted restoration activities with the technical support of the Bangladesh Forest Research Institute and other agencies. However, all the restoration activities for the Sundarbans, Chakaria Sundarbans, and coastal afforested sites had some success and failure stories. The success and failure of a mangrove restoration activity depends on planning (active or passive restoration), selection of suitable sites and species, planting materials, local community involvement, monitoring, evaluation and plantation management.
基金funded by Vietnam National University Ho Chi Minh City(VNU-HCM)under grant number B2019-18-09.
文摘Mangrove forest is always considered an effective barrier to protect habitats from high waves,especially tsunami.Therefore,the estimation of wave energy dissipation is required for disater warning.The aim of this study is to calculate wave attenuation in mangrove areas by combining field survey method and mathematical modeling method.The application area is Cu Lao Dung mangrove forest,Soc Trang,Vietnam.From data measurements of hydrodynamics and mangrove characteristics,the wave attenuation coefficient r,the drag coefficient Cd were determined in mud area,mud-mangrove area and mangrove area.In addition,using WAPROMAN model,the attenuation of wave height is simulated in different cases such as without mangrove,with mangrove,breaking wave effect and wave trunk interaction effect.Both the results from the measured method and the model method show the role of mangroves in reducing wave energy.The results from modeling are smaller than the calculated results.However,both methods tend to be suitable.Such difference required more considerations not only on calculation formulas but also on modeling adjustment.The research clearly demonstrated the effectiveness of mangroves in coastal protection,with wave-trunk interaction becoming the dominant factor in energy dissipation deeper into the forest.For future,extending the study to different mangrove forests and longer time scales could provide a more comprehensive understanding of the role of mangroves in coastal protection across various geographical and temporal contexts.
基金supported by China Geological Survey(DD20211301).
文摘This research investigates the ecological importance,changes,and status of mangrove wetlands along China’s coastline.Visual interpretation,geological surveys,and ISO clustering unsupervised classification methods are employed to interpret mangrove distribution from remote sensing images from 2021,utilizing ArcGIS software platform.Furthermore,the carbon storage capacity of mangrove wetlands is quantified using the carbon storage module of InVEST model.Results show that the mangrove wetlands in China covered an area of 278.85 km2 in 2021,predominantly distributed in Hainan,Guangxi,Guangdong,Fujian,Zhejiang,Taiwan,Hong Kong,and Macao.The total carbon storage is assessed at 2.11×10^(6) t,with specific regional data provided.Trends since the 1950s reveal periods of increase,decrease,sharp decrease,and slight-steady increases in mangrove areas in China.An important finding is the predominant replacement of natural coastlines adjacent to mangrove wetlands by artificial ones,highlighting the need for creating suitable spaces for mangrove restoration.This study is poised to guide future mangroverelated investigations and conservation strategies.
基金Under the auspices of the National Key Research and Development Program of China (No.2017YFA0604902,2017YFA0604903,2017YFA0604901)。
文摘Mangroves play a pivotal role in tropical and subtropical coastal ecosystem,yet they are highly vulnerable to the effects of climate change,particularly the accelerated global sea level rise(SLR)and stronger tropical cyclones(TCs).However,there is a lack of research addressing future simultaneous combined impacts of the slow-onset of SLR and rapid-onset of TCs on China's mangroves.In order to develop a comprehensive risk assessment method considering the superimposed effects of these two factors and analyze risk for mangroves in Dongzhaigang,Hainan Island,China,we used observational and climate model data to assess the risks to mangroves under low,intermediate,and very high greenhouse gas(GHG)emission scenarios(such as SSP1-2.6,SSP2-4.5,and SSP5-8.5)in 2030,2050,and 2100,and compiled a risk assessment scheme for mangroves in Dongzhaigang,China.The results showed that the combined risks from SLR and TCs will continue to rise;however,SLRs will increase in intensity,and TCs will decrease.The comprehensive risk of the Dongzhaigang mangroves posed by climate change will remain low under SSP1-2.6 and SSP2-4.5 scenarios by 2030,but it will increase substantially by 2100.While under SSP5-8.5 scenario,the risks to mangroves in Dongzhaigang are projected to increase considerably by 2050,and approximately 68.8%of mangroves will be at very high risk by 2100.The risk to the Dongzhaigang mangroves is not only influenced by the hazards but also closely linked to their exposure and vulnerability.We therefore propose climate resilience developmental responses for mangroves to address the effects of climate change.This study for the combined impact of TCs and SLR on mangroves in Dongzhaigang,China can enrich the method system of mangrove risk assessment and provide references for scientific management.
基金the Major Program of the National Fund of Philosophy and Social Science of China(Nos.21&ZD109).
文摘Mangrove ecosystems have important ecological and economic values,especially their ability to store carbon.However,in recent years,human disturbance has accelerated mangrove degradation.Among them,the emission of pollutants cannot be ignored.It is of great significance for carbon emission reduction and ecological protection to study the impacts of different pollutants on mangroves and their carbon stocks.Based on the remote sensing data of coastal areas south of the Yangtze River in China's Mainland,this paper builds the ensemble learning model Random Forest(RF)and Gradient Boosting Regression(GBR)to empirically analyse the relationship between industrial wastewater,industrial sulfur dioxide(SO2),PM2.5 and mangrove forests.The results show that the pollutant concentration of meteorological normalisation is more stable.The importance of pollutants presents regional heterogeneity.The area of mangroves in different cities and the corresponding total carbon stocks show different trends with the increase or decrease of pollutants,and there is a dynamic balance between urban pollutant discharge and mangrove growth in some cities.The research in this paper provides an analysis and explanation from the perspective of machine learning to explore the relationship between mangroves and pollutants and at the same time,provides scientific suggestions for the formulation of future pollutant emission policies in different cities.
基金financially supported by the Geological Survey Project of China Geological Survey(No.DD20190304)。
文摘Mangrove wetlands are among the four most productive tropical and subtropical ecosystems.They are also a core component of the coastal blue carbon ecosystem,which is of great ecological significance to human beings,plants,animals,and the global carbon balance.There has been a global decrease in the distribution of mangrove forests,and their ecological function has gradually degenerated since the Holocene.Sediment from coastal mangrove wetlands can provide records of climate change and human activities,and multiple proxies including palynology,leaf fossil,biomarkers,DNA,phytolith and stable isotopes,can be used to reconstruct the evolutionary stages of paleo-mangroves and to identify the effect of natural processes and human activities on the distribution and evolution of mangroves.This information can provide theoretical support for mangrove protection and for improving carbon sequestration capacity.This paper summarizes and compares the multiple proxies for mangrove reconstruction,reviews progress in the study of natural succession of global mangroves since the Holocene,expands on the influence mechanisms of human activities on mangrove growth and development and uses past information to lay a foundation for a model to predict future mangrove development.
基金This study was funded by the Forestry Administration of Guangdong Province(2022KJCX014)the Guangdong Basic and Applied Basic Research Foundation(2022A1515010550)the Department of Science and Technology of Guangdong Province,China(2019B121202003).
文摘Salinity is among the most critical factors limiting the growth and species distribution of coastal plants.Water salinity in estuarine ecosystems varies temporally and spatially,but the variation patterns across different time scales and salinity fluctuation have rarely been quantified.The effects of salinity on floristic diversity in mangroves are not fully understood due to the temporal and spatial heterogeneity of salinity.In this study,we monitored water salinity at an interval of 10-min over one year in three mangrove catchment areas representing the outer part,middle part,and inner part respectively of Dongzhai Bay,Hainan,China.The number of mangrove community types and dominant mangrove species of the three catchment areas were also investigated.We found that the diurnal variation and dry-season intra-month variation in water salinity were driven by tidal cycles.The seasonal variation in water salinity was mainly driven by rainfall with higher salinity occurring in the dry season and lower salinity occurring in the wet season.Spatially,water salinity was highest at the outer part,intermediate at the middle part,and lowest at the inner part of the bay.The intra-month and annual fluctuations of water salinity were highest at the middle part and lowest at the outer part of the bay.The number of mangrove community types and dominant species were lowest at the outer part,intermediate at the middle part,and highest at the inner part of the bay.These results suggest that the temporal variation of water salinity in mangroves is driven by different factors at different time scales and therefore it is necessary to measure water salinity at different time scales to get a complete picture of the saline environment that mangroves experience.Spatially,lower salinity levels benefit mangrove species richness within a bay landscape,however,further research is needed to distinguish the effects of salinity fluctuation and salinity level in affecting mangrove species richness.
基金This study is supported by the Key Program of National Natural Science Foundation of China (39830310).
文摘This paper reviews and discusses the technical terms and definition of mangrove and mangal, as well as mangrove plant. The word mangrove has been used to refer either to the constituent plant of tropical and subtropical intertidal community or to the community itself, but this usage makes more confusion. Being leaved mangrove in the more limited sense for the constituent plant species, mangal was proposed by MacNae (1968) as a term for mangrove community, which has been universally applied to most previous studies and should be adopted now. Mangrove should be therefore defined as a tropical and subtropical tree restricted to intertidal zones, which possesses some morphological specializion and physiological mechanism adapted to its habitat, and mangal as a tropical and subtropical forest community restricted to marine intertidal zones and periodically inundeated by the tides. A new term "consortive plant" is proposed here for herb, liana, epiphyte or parasite, which is restricted in the strict mangrove habitat.
文摘Mangrove forests in southern Iran are of high ecological and economic importance.These forests are being threatened because of uncontrolled harvesting to provide fodder for livestock.The objective of this study is to provide recommendations for appropriate harvesting intensities by quantifying the effect of different harvesting intensities on vegetative and vigor characteristics of mangrove trees.This study was conducted using a randomized complete block design comprising four treatments(10.00%,20.00%,and 30.00% trimming,along with a control)replicated three times.Vegetative characteristics were measured before and after trimming(five-year period)and analyzed using generalized linear model statistical analysis.The growths of the average diameter of canopy,canopy area,canopy volume,canopy height,tree height,and collar diameter in the control treatment were all significantly higher than those in the trimming treatments.In addition,there was a decreasing trend in leaf fresh and dry mass,leaf area index,total area of canopy leaves,and health status of tree in the trimming treatments.For example,the percentage change in fresh and dry leaf mass in the control treatment was positive(29.87% and 38.31%,respectively),whereas the trimming treatments of 10.00%,20.00% and 30.00% had negative effects(-7.01% and -4.79%,-11.32% and -14.30%,and -15.84% and -17.29%,respectively).In addition,the changes in leaf area index in the control(4.95%)and 30.00% trimming(-24.57%)treatments were the highest and lowest,respectively.The percentage change in soil organic matter in the control,10.00%,20.00%,and 30.00% treatments were 22.94%,-9.90%,-16.91%,and -18.68%,respectively.The study demonstrated that gray mangrove trees were highly sensitive to canopy trimming,with even minimal trimming intensities negatively affecting vegetative growth and soil organic matter.Therefore,it is recommended that cutting and trimming of mangrove trees should be prevented even at low intensity to preserve mangrove ecosystem health and resilience against environmental stressors.
基金funded by the National Key R&D Program of China(No.2023YFC3007900)the Young Scientists Fund of the National Natural Science Foundation of China(No.42106204)+2 种基金the Jiangsu Basic Research Program(Natural Science Foundation)(No.BK20220082)the National Natural Science Foundation of China(No.52271271)the Major Science&Technology Projects of the Ministry of Water Resources(No.SKS-2022025).
文摘This paper provides a comprehensive overview on coastal protection and hazard mitigation by mangroves.Previous stud-ies have made great strides to understand the mechanisms and influencing factors of mangroves’protection function,including wave energy dissipation,storm surge damping,tsunami mitigation,adjustment to sea level rise and wind speed reduction,which are sys-tematically summarized in this study.Moreover,the study analyzes the extensive physical models,based on indoor flume experi-ments and numerical models,that consider the interaction between mangroves and hydrodynamics,to help our understanding of mangrove-hydrodynamic interactions.Additionally,quantitative approaches for valuing coastal protection services provided by man-groves,including index-based and process-resolving approaches,are introduced in detail.Finally,we point out the limitations of previous studies,indicating that efforts are still required for obtaining more long-term field observations during extreme weather events,to create more real mangrove models for physical experiments,and to develop numerical models that consider the flexible properties of mangroves to better predict wave propagation in mangroves having complex morphology and structures.
基金The Key R&D Project of Hainan Province under contract No.ZDYF2023SHFZ097the National Natural Science Foundation of China under contract No.42376180。
文摘Mangroves are indispensable to coastlines,maintaining biodiversity,and mitigating climate change.Therefore,improving the accuracy of mangrove information identification is crucial for their ecological protection.Aiming at the limited morphological information of synthetic aperture radar(SAR)images,which is greatly interfered by noise,and the susceptibility of optical images to weather and lighting conditions,this paper proposes a pixel-level weighted fusion method for SAR and optical images.Image fusion enhanced the target features and made mangrove monitoring more comprehensive and accurate.To address the problem of high similarity between mangrove forests and other forests,this paper is based on the U-Net convolutional neural network,and an attention mechanism is added in the feature extraction stage to make the model pay more attention to the mangrove vegetation area in the image.In order to accelerate the convergence and normalize the input,batch normalization(BN)layer and Dropout layer are added after each convolutional layer.Since mangroves are a minority class in the image,an improved cross-entropy loss function is introduced in this paper to improve the model’s ability to recognize mangroves.The AttU-Net model for mangrove recognition in high similarity environments is thus constructed based on the fused images.Through comparison experiments,the overall accuracy of the improved U-Net model trained from the fused images to recognize the predicted regions is significantly improved.Based on the fused images,the recognition results of the AttU-Net model proposed in this paper are compared with its benchmark model,U-Net,and the Dense-Net,Res-Net,and Seg-Net methods.The AttU-Net model captured mangroves’complex structures and textural features in images more effectively.The average OA,F1-score,and Kappa coefficient in the four tested regions were 94.406%,90.006%,and 84.045%,which were significantly higher than several other methods.This method can provide some technical support for the monitoring and protection of mangrove ecosystems.
基金supported by the National Key R&D Program of China(No.2022YFD2401304)。
文摘Since the 1980s,the robust economic growth of China has prompted extensive land reclamation projects along its coastline,notably affecting local hydrodynamics and resulting in ecological repercussions.Using a nearshore finite volume ocean model,we constructed a hydrodynamic model for Shacheng Bay,a southeastern coastal region with a winding and narrow entrance.We examined the hydrodynamic changes and mangrove dynamics over the past 36 years and the relationship between hydrodynamic alterations and mangrove degradation.Simulation results reveal that extensive reclamation projects between 1984 and 2000 weakened the current in Shacheng Bay,leading to decreased water exchange capacity and a significant reduction in mangrove area from 0.3 to 0.06km^(2).During this period,over 37% of mangrove degradation was ascribed to time-changing hydrodynamic variables without the direct influence of land reclamation.The results also highlight the changes in local hydrodynamics and water exchange patterns that adversely influenced mangrove growth.From 2000 to 2020,there were minimal coastline changes in Shacheng Bay,demonstrating reduced land reclamation activities.This stopped the further weakening trend of the currents,with a slight increase during ebb tides,while the residual current continued to weaken due to the decreasing tidal prism and water exchange capacity.The mangrove area partially recovered during this period,expanding from 0.06 to 0.11 km^(2),predominantly in new areas instead of where mangroves disappeared from 1984 to 2000.This work underlines the intricate relationship between land reclamation,hydrodynamics,and mangrove ecosystems,underscoring the need for sustainable coastal development strategies.
基金National Natural Science Foundation of China(Nos.U20A2001,81973195,21877133)the Guangdong Marine Economy Development Special Project(Nos.GDNRC[2022]35,GDNRC[2023]39)。
文摘(±)-Mycosphatide A(1a/1b),a pair of highly oxidized enantiomeric polyketides featuring a unique5/5/6/5-fused tetracyclic ring system,were isolated from the mangrove endophytic fungus Mycosphaerella sp.SYSU-DZG01.Their structures were established by extensive spectroscopic analyses,single crystal Xray diffraction,and experimental electronic circular dichroism(ECD)spectra comparison.The plausible biosynthetic pathway of 1 was proposed,which involved the generation of a key spiro[4.5]decane scaffold.Compounds(+)-1a and(-)-1b exhibited significant lipid-lowering activity in 3T3-L1 adipocytes model,with EC50values of 7.85±1.56 and 8.87±0.80μmol/L,respectively.
基金The Scientific Research Foundation of the Third Institute of Oceanography,Ministry of Natural Resources under contract Nos TIO2020008 and TIO2019028the Project of Marine Protected Areas Network in China-ASEAN Countries,National Key Research and Development Programe under contract No.2017YFC1405100the National Science Foundation of China under contract No.41976050.
文摘Global carbon cycle has received extensive attention,among which the river-estuary system is one of the important links connecting the carbon cycle between land and ocean.In this paper,the distribution and control factors of particulate organic carbon(POC)were studied by using the data of organic carbon contents and its carbon isotopic composition(δ13C)in the mainstream and estuary of Passur River in the Sundarbans area,combined with the hydrological and biological data measured by CTD.The results show that POC content ranged from 0.263 mg/L to 9.292 mg/L,and the POC content in the river section(averaged 4.129 mg/L)was significantly higher than that in the estuary area(averaged 0.858 mg/L).Two distinct stages of POC transport from land to sea in the Sundarbans area were identified.The first stage occurred in the river section,where POC distribution was mainly controlled by the dynamic process of runoff and the organic carbon was mainly terrestrial source.The second stage occurred during estuarine mixing,where the POC distribution was mainly controlled by the mixing process of seawater and freshwater.The source of POC was predominantly marine and exhibiting vertical differences.The surface and middle layers were primarily influenced by marine sources,while the bottom layer was jointly controlled by terrestrial and marine sources of organic carbon.These findings are of great significance for understanding the carbon cycle in such a large mangrove ecosystem like the Sundarbans mangrove.
基金supported by the Key-Area Research and Development Program of Guangdong Province(No.2023B1111050008)the National Natural Science Foundation of China(Nos.U23A20528,U20A20101)+1 种基金Guangdong Local Innovation Team Program(No.2019BT02Y262)the Postdoctoral Fellowship Program of CPSF(No.GZC20232777).
文摘Seven novel linear polyketides,talaketides A-G(1-7),were isolated from the rice media cultures of the mangrove sed-iment-derived fungus Talaromyces sp.SCSIO 41027.Among these,talaketides A-E(1-5)represented unprecedented unsaturated lin-ear polyketides with an epoxy ring structure.The structures,including absolute configurations of these compounds,were elucidated through detailed analyses of nuclear magnetic resonance(NMR)and high-resolution mass spectrometry(HR-MS)data,as well as elec-tronic custom distributors(ECD)calculations.In the cytotoxicity screening against prostate cancer cell lines,talaketide E(5)demon-strated a dose-dependent inhibitory effect on prostate cancer PC-3 cell lines,with an IC50 value of 14.44 μmol·L-1.Moreover,com-pound 5 significantly inhibited the cloning formation of PC-3 cell lines and arrested the cell cycle in S-phase,ultimately inducing ap-optosis.These findings indicate that compound 5 may serve as a promising lead compound for the development of a potential treat-ment for prostate cancer.
