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
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
The intertidal zone of mangroves has a significant impact on the ecological environment by serving as a crucial habitat for a wide range of organisms.When assessing heavy metal contamination in sediments within this z...The intertidal zone of mangroves has a significant impact on the ecological environment by serving as a crucial habitat for a wide range of organisms.When assessing heavy metal contamination in sediments within this zone,it is essential to establish a regional geochemical baseline that accounts for natural variations.In this study,regional geochemical baselines of heavy metals were established based on core sediment samples collected from Dongzhai Harbor in November 2015.Linear regression analysis was employed to examine the correlations between heavy metals and potential normalized elements.Subsequently,the sediment quality and intensity of pollutant input in the sediments of a mangrove intertidal zone were evaluated with enrichment factor(EF)and excessive influx of heavy metals.The EF values for Cr,Cd,Pb,Zn,and Ni in the study area were all below 1.5,indicating minimal levels of contamination;however,minor Cu contamination was observed in the high tidal flat area due to potential terrestrial inputs.These findings suggest that the overall environmental quality about heavy metals was good within the intertidal zone of mangroves.Moreover,as for the excess fluxes of heavy metals in intertidal sediments,there was consistency between influence and intervention of human activities on sedimentary environment during the selected period when examining variation trends.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 forests are critical ecosystems for carbon sequestration,effectively capturing atmospheric carbon and permanently storing soil organic carbon(SOC)in coastal wetlands.Recent restoration and afforestation initi...Mangrove forests are critical ecosystems for carbon sequestration,effectively capturing atmospheric carbon and permanently storing soil organic carbon(SOC)in coastal wetlands.Recent restoration and afforestation initiatives have been undertaken to mitigate the rising atmospheric CO_(2) concentrations along tropical ocean coasts worldwide.The expansion of mangrove forests has garnered significant attention for elucidating their contributions to the permanent storage of carbon in both surface and subsoil layers.In this study,we investigated a recently expanding mangrove forest in the Beilun River Estuary of Guangxi Province,focusing on the abundance and sources of organic carbon(OC)in surface sediments.We also analyzed sediment grain size distribution,SOC,total nitrogen(TN)content,and stable carbon isotope composition(δ^(13)C).Additionally,we determined the molar ratio of SOC to nitrogen(C/N).The SOC content ranged from 0.25%to 6.58%,the C/N ratio varied from 9.85 to 17.73,δ^(13)C values spanned from-29.58‰to-24.93‰,andδ^(15)N values ranged from 3.10‰to 7.36‰.A strong correlation was observed between SOC and TN content.However,particle size did not significantly influence these relationships.In terms of SOC sources in the sediments,contributions from mangrove,terrestrial,and marine sources accounted for 37.1%to 99.5%,0.5%to 47.4%,and 0%to 17.6%,respectively.The findings of this study provide essential insights for evaluating and managing carbon sinks within the mangrove ecosystems of the Beibu Gulf region,contributing to more effective carbon management strategies in coastal areas.展开更多
The increased erosion of mangrove forests has alarmed the government about the damage to both the economy and livelihoods.To evaluated forest and land erosion the coast.Based on survey data is divided into five levels...The increased erosion of mangrove forests has alarmed the government about the damage to both the economy and livelihoods.To evaluated forest and land erosion the coast.Based on survey data is divided into five levels(F1:no erosion;F2:little erosion;F3:moderate erosion;F4:high erosion;F5:strong erosion),and ecological conditions,the coast is divided into sub-regions for investigation.From the surveyed indicators at each erosion level,forest structure is analyzed for comparison.The erosion level is defined as an erosion function(Er)from 1 to 5(+),where(1)parameters include the number of trees per hectare(Ntr/ha),height to top(Ht),trunk diameter at 1.3 m(D1.3),tree canopy diameter(Dc),and width of the forest range(Wf);(2)land erosion is a function(Erl=Erlte+Erlsa+Erlsi+Erlcl),with parameters including erosion by terrain(Erlte),sand(Erlsa),silt(Erlsi),and clay(Erlcl);and(3)climate change leading to erosion is an inverse function(Cl)from 1 to 5(-),with parameters including erosion by rainfall(Clra),wind(Clwi),waves(Clwa),and tide(Clti).The resulting function output is Er=(Erf+Erl)-Cl.On eroded forest land,species were tested under climate change conditions and their growth in the next rainy season to assess survival rates affected by rainfall,waves,wind,and tides.These results help to plan planting mangrove forest anti-erosion models and construct a theoretical function of mangrove erosion and proposes restore forests using pioneer species.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
Mangroves are increasingly being degraded in West Africa. We explored local utilization, threats and assessed existing conservation practices in Ghana through field visits, mapping, laboratory analyses and interviews....Mangroves are increasingly being degraded in West Africa. We explored local utilization, threats and assessed existing conservation practices in Ghana through field visits, mapping, laboratory analyses and interviews. The study reports three species of mangroves along Ghana’s coastline;white (Avicennia germinans), red (Rhizophora racemosa), and black (Laguncularia racemosa) mangroves. White mangrove is the most dominant, with black mangroves being the least. The current mangrove cover of Ghana was estimated at 72.4 km<sup>2</sup> with over 18 million trees (average = 2284.21 trees per hectare), both naturally occurring and planted mangroves. The Volta Region had the most abundant mangroves, with the Central region recording the least. Notable flora within the mangrove forests included Acrostichum aureum, Sesuvium portulacastrum, Paspalum vaginatum, Sporobolus maritima and Conocarpus erectus. Mangrove wetland in Ghana provides suitable nursery habitats for several important fish species, including Sarotherodon melanotheron, Mugil cephalus, Callinectes amnicola, Cardiosoma armatum, Crassostrea sp, Periophthalmus papilio, Coptodon spp. Ghana’s mangrove forest is declining at a rate of 8.1 km<sup>2</sup> per annum due to over-cutting, land conversion, wildfires, pollution, overgrazing and natural death from disease. Over cutting mangrove for fish smoking and housing construction were significant threats to mangroves nationwide. Continuous education, law enforcement, nature-based methods and local control mechanisms effectively protect mangroves.展开更多
Located between terrestrial and marine ecosystems,mangrove forests are sensitive to changes in climate.The responses of mangrove ecosystems to climate change in the future can be understood by reconstructing past mang...Located between terrestrial and marine ecosystems,mangrove forests are sensitive to changes in climate.The responses of mangrove ecosystems to climate change in the future can be understood by reconstructing past mangrove dynamics using proxies preserved in the intertidal sediments.Considering the complexity of the proxies commonly used,it is necessary to develop a relatively simple,inexpensive proxy.In this study,available chemical tracers(δ13Corg and C:N)of the four cores(YLW02,YLW03,O18,and Q37)from the intertidal zone of the northern Beibu Gulf(NBG)and a three-end-member(mangrove,sea grass,and suspended particulate matter)model was utilized to determine the contribution of mangrove-derived organic matter(CMOM)in carbonate-free sediments.Compared with the summed concentration of mangrove pollen(SCMP),a significant positive correlation between CMOM and SCMP is displayed.The calculated CMOM for an additional 210Pb-dated sediment core from the Yingluo Bay,NBG(YLW01)clearly indicates a mangrove development going through degradation,flourishing,relative degradation,and relative flourishing,which are separately in correspondence with the lowest,highest,lower,and higher air temperature and rainfall in the time intervals of 1890–1918 AD,1919–1956 AD,1957–1990 AD,and 1991–2010 AD.This suggests that CMOM preserved in intertidal sediments has a potential to reconstruct historical mangrove development in high resolution,at the very least,along the coasts of the NBG.展开更多
The species composition and characteristics of mangrove flora in the world were reviewed and discussed. The results suggested that the world's mangrove plants have 84 species (including 12 varieties) in 24 genera ...The species composition and characteristics of mangrove flora in the world were reviewed and discussed. The results suggested that the world's mangrove plants have 84 species (including 12 varieties) in 24 genera and 16 families. Of which, true mangrove plants have 70 species (including 12 varieties) in 16 genera and 11 families, and semi-mangrove plants 14 species in eight genera and five families. The Eastern Group has 74 species (including 12 varieties) in 18 genera and 14 families, characterized by the genera Aegiceras, Osbornia, Aegialitis, Bruguiera, Ceriops, Kandelia, Scyphiphora and Nypa etc. The Western Group has only 10 species in six genera and five families, characterized by the endemic one-species family, Pelliceraceae, and the genus Laguncularia. The mangrove flora of China is composed of 26 species (including one variety) in 15 genera and 12 families, four of which are endemic. Hainan is most rich in mangrove species, making up about 96.2% of the Chinese total; Guangdong ranks second, making up about 42.3%. It has been demonstrated that Rhizophora stylosa was mistaken for R. mucronata in Taiwan by previous authors.展开更多
An unusual diterpenoid excoagallochaol A (1), together with epi-β-amyrin (2), epitaraxerol (3), epi-a-amyrin (4), epilupeol (5), betulin (6), betulinic acid (7), lupenone (8), betulone (9), betuloni...An unusual diterpenoid excoagallochaol A (1), together with epi-β-amyrin (2), epitaraxerol (3), epi-a-amyrin (4), epilupeol (5), betulin (6), betulinic acid (7), lupenone (8), betulone (9), betulonic acid (10), (9Z,12Z,15Z)-2,3-dihydroxypropyl octadecatrienoate (11), and (9Z,12Z)-2,3-dihydroxypropyl octadecadienoate (12)were isolated from the stems of Excoecaria agallocha L. Their structures were elucidated by spectroscopic analyses, and the absolute stereochemistry of 1 was assigned using Mosher method. Compounds 4, 8, 10-12 were isolated from the genus Excoecaria for the first time.展开更多
The characteristics of macrofauna communities in three mangrove assemblages [Avicennia marina+Acgiceras corniculatum (MC)community, A.corniculatum (C) community and Bruguiera gymnorrhiza+A.corniculatum (GC) co...The characteristics of macrofauna communities in three mangrove assemblages [Avicennia marina+Acgiceras corniculatum (MC)community, A.corniculatum (C) community and Bruguiera gymnorrhiza+A.corniculatum (GC) community] were studied in Zhanjiang Mangrove Nature Reserves during 2005 and 2006. Of the three mangrove assemblages, the macrofauna species number, density, biomass, Richness index and Shannon-Wiener index were the highest, and the Simpson dominance index was medial at MC community. However the Pielou Evenness index of MC community was slightly lower than that at C community. At C community, the number of macrofauna species obviously reduced, especially infaunal, caving and adhering life forms, and the biomass and density were the lowest. Because of the even distribution of individuals of different species, the Simpson dominance index was the lowest and the evenness index was the highest. Although the Richness index at C community was slightly lower than that at MC community, the Shannon-Wiener index was near to that at MC community. At GC community, the number of macrofauna species, especially infaunal and caving life forms, continued to decrease comparing C community, but the biomass and density increased slightly. As the distribution of individuals of different species was uneven, the Simpson dominance index was the highest and the Pielou Evenness index was the lowest. Furthermore, the Richness index dropped to the lowest. The Shannon-Wiener index also dropped accordingly to the lowest. The dominant life forms of MC were infaunal and caving, while those of C and GC community were both caving. The ratio of the GS/GSB of macrofauna communities in the three mangrove assemblages were 0.48, 0.63 and 0.80, respectively. The community structures at the same mangrove assemblages were all quite similar, with those at GC community being most similar. However, there were obvious differences among the community structures at the three different mangrove assemblages. These results implied that the different mangrove assemblages had different affects on the macrofauna communities and shed light on the macrofauna adaptation capability to specific habitats.展开更多
Leizhou Peninsula, located at southem end of mailand China, has 9 284.3 ha mangrove distributed more than 100 sites along its inlets and open coastlines. This paper presents the surveys on mangrove area in Leizhou Pen...Leizhou Peninsula, located at southem end of mailand China, has 9 284.3 ha mangrove distributed more than 100 sites along its inlets and open coastlines. This paper presents the surveys on mangrove area in Leizhou Peninsula during 2000 and 2008, especially the survey in the eight major mangrove areas in 2002. The flora recorded in mangrove systems includes 69 large algea species, 13 native true mangrove species, nine native semi-mangrove species, and another seven intoduced true mangrove species with Sonneratia apetala as the quickest growing exotic mangrove species dominatant in the mangrove plantations, and more than 100 land flora species, consisting of 17 main mangrove associations. The plant biodiversity habitats remained mainly small patches and diverse, and were becoming worse under the intensive disturbance of human acitivities and coastal pollutions, which decreased the value of mangrove coasts as the important sites for flying-by migrating birds in Leizhou Peninsula. The effective mangrove conservation measures should be implemented.展开更多
[Objective] The aim was to identify the species diversity of Actinomycetes from Mangrove forest in Beihai,Guangxi Province. [Method] 10 strains of typical Actinomycetes were isolated from Mangrove forest soil,and the ...[Objective] The aim was to identify the species diversity of Actinomycetes from Mangrove forest in Beihai,Guangxi Province. [Method] 10 strains of typical Actinomycetes were isolated from Mangrove forest soil,and the Actinomycetes genomic DNA was successful extracted. 16S rDNA was amplified by PCR and sequenced by Sanger dideoxy sequencing method. [Result] All the sequences were blasted in genbank,eight strains belonged to the genus of Streptomyces (80%),and two strains belonged to the genus of Nocardiopsis (20%). [Conclusion] There are many different Actinomycetes species in Mangrove forest soil samples in Beihai,Guangxi Province.展开更多
Based on total carbon(C) and C isotopes in sediment cores,sedimentary organic carbon(SOC) was quantified in three types of mangrove sites(barren flat sites without mangroves,mangrove plantations,and natural mangrove f...Based on total carbon(C) and C isotopes in sediment cores,sedimentary organic carbon(SOC) was quantified in three types of mangrove sites(barren flat sites without mangroves,mangrove plantations,and natural mangrove forests),which were considered to represent a continuum from least restored to most restored sites in southern China.SOC densities in the barren sites,plantations,and natural forests were 90,170 and 288 Mg ha 1,respectively.We inferred that mangrove restoration increased SOC accumulation in coastal areas.At 0-70 cm depth,SOC δ 13 C values in both mangrove sites ranged from 27.37‰ to 23.07‰ and exhibited gradual enrichment with depth.In contrast,the values in the barren flat sites remained around 22.19‰ and fluctuated slightly with depth.At 0-60 cm,the 14 C ages of the SOC in the barren flat site,the natural mangrove site,and the artificial mangrove site ranged from 1 397 to 2 608,255 to 2 453,and 391 to 2 512 years BP,respectively.In both types of mangrove sites but not in the barren flat sites,the enrichment of δ 13 C with depth was related to increases in SOC decay and SOC age with depth.According to analysis of 14 C age,much of the mangrove-derived C was transported and stored at 0-60 cm depth under anaerobic conditions in both mangrove sites.The sediments of mangrove forests in southern China sequester large quantities of SOC during mangrove restoration.展开更多
According to the survey of Guangdong mangrove resource in 2001 and authors field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for ...According to the survey of Guangdong mangrove resource in 2001 and authors field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for 41.4% of total mangrove land area of China. These mangrove forests totally consisted of 50 species belonging to 28 families, distributed at more than 100 locations along the coastlines of Guangdong and most of them present a high dense and dwarf appearance. The Ass. Avicennia marina is the most dominant mangrove association. The investigation results showed that the mangrove forests with coverage rates above 0.7 accounted for 68.0% of the total mangrove land area of the province and 77.8% of mangrove forests was less than 2 m in tree height. Since 1950, 54.6% of mangrove forests have disappeared due to paddy rice reclaim, aquaculture and city constructions. Derivational conservation efforts are still weakly empowered and should be strengthened intensively. The author suggested that mangrove laws and regulations should be enforced, mangrove scientific research should be strengthened; and mangrove conservation awareness of local community should be raised on conservation of mangroves.展开更多
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.
基金Supported by the Project of Investigation on the Background and Quality of Representative Intertidal Sediments in China and Compilation of Atlas,Ministry of Science and Technology of the People’s Republic of China(No.2014FY210600)the National Natural Science Foundation of China(No.41807247)。
文摘The intertidal zone of mangroves has a significant impact on the ecological environment by serving as a crucial habitat for a wide range of organisms.When assessing heavy metal contamination in sediments within this zone,it is essential to establish a regional geochemical baseline that accounts for natural variations.In this study,regional geochemical baselines of heavy metals were established based on core sediment samples collected from Dongzhai Harbor in November 2015.Linear regression analysis was employed to examine the correlations between heavy metals and potential normalized elements.Subsequently,the sediment quality and intensity of pollutant input in the sediments of a mangrove intertidal zone were evaluated with enrichment factor(EF)and excessive influx of heavy metals.The EF values for Cr,Cd,Pb,Zn,and Ni in the study area were all below 1.5,indicating minimal levels of contamination;however,minor Cu contamination was observed in the high tidal flat area due to potential terrestrial inputs.These findings suggest that the overall environmental quality about heavy metals was good within the intertidal zone of mangroves.Moreover,as for the excess fluxes of heavy metals in intertidal sediments,there was consistency between influence and intervention of human activities on sedimentary environment during the selected period when examining variation trends.
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The National Natural Science Foundation of China under contract No.42476043the Guangxi Key Research and Development Project under contract No.AB21076016+2 种基金the Scientific Research and Technology Development Project of Qinzhou under contract No.202116623the Natural Science Foundation of Guangxi under contract No.2021GXNSFAA075013the China College Students’Innovation and Entrepreneurship Training Program Project under contract No.S202411607002。
文摘Mangrove forests are critical ecosystems for carbon sequestration,effectively capturing atmospheric carbon and permanently storing soil organic carbon(SOC)in coastal wetlands.Recent restoration and afforestation initiatives have been undertaken to mitigate the rising atmospheric CO_(2) concentrations along tropical ocean coasts worldwide.The expansion of mangrove forests has garnered significant attention for elucidating their contributions to the permanent storage of carbon in both surface and subsoil layers.In this study,we investigated a recently expanding mangrove forest in the Beilun River Estuary of Guangxi Province,focusing on the abundance and sources of organic carbon(OC)in surface sediments.We also analyzed sediment grain size distribution,SOC,total nitrogen(TN)content,and stable carbon isotope composition(δ^(13)C).Additionally,we determined the molar ratio of SOC to nitrogen(C/N).The SOC content ranged from 0.25%to 6.58%,the C/N ratio varied from 9.85 to 17.73,δ^(13)C values spanned from-29.58‰to-24.93‰,andδ^(15)N values ranged from 3.10‰to 7.36‰.A strong correlation was observed between SOC and TN content.However,particle size did not significantly influence these relationships.In terms of SOC sources in the sediments,contributions from mangrove,terrestrial,and marine sources accounted for 37.1%to 99.5%,0.5%to 47.4%,and 0%to 17.6%,respectively.The findings of this study provide essential insights for evaluating and managing carbon sinks within the mangrove ecosystems of the Beibu Gulf region,contributing to more effective carbon management strategies in coastal areas.
文摘The increased erosion of mangrove forests has alarmed the government about the damage to both the economy and livelihoods.To evaluated forest and land erosion the coast.Based on survey data is divided into five levels(F1:no erosion;F2:little erosion;F3:moderate erosion;F4:high erosion;F5:strong erosion),and ecological conditions,the coast is divided into sub-regions for investigation.From the surveyed indicators at each erosion level,forest structure is analyzed for comparison.The erosion level is defined as an erosion function(Er)from 1 to 5(+),where(1)parameters include the number of trees per hectare(Ntr/ha),height to top(Ht),trunk diameter at 1.3 m(D1.3),tree canopy diameter(Dc),and width of the forest range(Wf);(2)land erosion is a function(Erl=Erlte+Erlsa+Erlsi+Erlcl),with parameters including erosion by terrain(Erlte),sand(Erlsa),silt(Erlsi),and clay(Erlcl);and(3)climate change leading to erosion is an inverse function(Cl)from 1 to 5(-),with parameters including erosion by rainfall(Clra),wind(Clwi),waves(Clwa),and tide(Clti).The resulting function output is Er=(Erf+Erl)-Cl.On eroded forest land,species were tested under climate change conditions and their growth in the next rainy season to assess survival rates affected by rainfall,waves,wind,and tides.These results help to plan planting mangrove forest anti-erosion models and construct a theoretical function of mangrove erosion and proposes restore forests using pioneer species.
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.
文摘Mangroves are increasingly being degraded in West Africa. We explored local utilization, threats and assessed existing conservation practices in Ghana through field visits, mapping, laboratory analyses and interviews. The study reports three species of mangroves along Ghana’s coastline;white (Avicennia germinans), red (Rhizophora racemosa), and black (Laguncularia racemosa) mangroves. White mangrove is the most dominant, with black mangroves being the least. The current mangrove cover of Ghana was estimated at 72.4 km<sup>2</sup> with over 18 million trees (average = 2284.21 trees per hectare), both naturally occurring and planted mangroves. The Volta Region had the most abundant mangroves, with the Central region recording the least. Notable flora within the mangrove forests included Acrostichum aureum, Sesuvium portulacastrum, Paspalum vaginatum, Sporobolus maritima and Conocarpus erectus. Mangrove wetland in Ghana provides suitable nursery habitats for several important fish species, including Sarotherodon melanotheron, Mugil cephalus, Callinectes amnicola, Cardiosoma armatum, Crassostrea sp, Periophthalmus papilio, Coptodon spp. Ghana’s mangrove forest is declining at a rate of 8.1 km<sup>2</sup> per annum due to over-cutting, land conversion, wildfires, pollution, overgrazing and natural death from disease. Over cutting mangrove for fish smoking and housing construction were significant threats to mangroves nationwide. Continuous education, law enforcement, nature-based methods and local control mechanisms effectively protect mangroves.
基金The National Natural Science Foundation of China under contract No.41576061the Basic Scientific Fund for National Public Research Institutes of China under contract No.2017Q03
文摘Located between terrestrial and marine ecosystems,mangrove forests are sensitive to changes in climate.The responses of mangrove ecosystems to climate change in the future can be understood by reconstructing past mangrove dynamics using proxies preserved in the intertidal sediments.Considering the complexity of the proxies commonly used,it is necessary to develop a relatively simple,inexpensive proxy.In this study,available chemical tracers(δ13Corg and C:N)of the four cores(YLW02,YLW03,O18,and Q37)from the intertidal zone of the northern Beibu Gulf(NBG)and a three-end-member(mangrove,sea grass,and suspended particulate matter)model was utilized to determine the contribution of mangrove-derived organic matter(CMOM)in carbonate-free sediments.Compared with the summed concentration of mangrove pollen(SCMP),a significant positive correlation between CMOM and SCMP is displayed.The calculated CMOM for an additional 210Pb-dated sediment core from the Yingluo Bay,NBG(YLW01)clearly indicates a mangrove development going through degradation,flourishing,relative degradation,and relative flourishing,which are separately in correspondence with the lowest,highest,lower,and higher air temperature and rainfall in the time intervals of 1890–1918 AD,1919–1956 AD,1957–1990 AD,and 1991–2010 AD.This suggests that CMOM preserved in intertidal sediments has a potential to reconstruct historical mangrove development in high resolution,at the very least,along the coasts of the NBG.
文摘The species composition and characteristics of mangrove flora in the world were reviewed and discussed. The results suggested that the world's mangrove plants have 84 species (including 12 varieties) in 24 genera and 16 families. Of which, true mangrove plants have 70 species (including 12 varieties) in 16 genera and 11 families, and semi-mangrove plants 14 species in eight genera and five families. The Eastern Group has 74 species (including 12 varieties) in 18 genera and 14 families, characterized by the genera Aegiceras, Osbornia, Aegialitis, Bruguiera, Ceriops, Kandelia, Scyphiphora and Nypa etc. The Western Group has only 10 species in six genera and five families, characterized by the endemic one-species family, Pelliceraceae, and the genus Laguncularia. The mangrove flora of China is composed of 26 species (including one variety) in 15 genera and 12 families, four of which are endemic. Hainan is most rich in mangrove species, making up about 96.2% of the Chinese total; Guangdong ranks second, making up about 42.3%. It has been demonstrated that Rhizophora stylosa was mistaken for R. mucronata in Taiwan by previous authors.
文摘An unusual diterpenoid excoagallochaol A (1), together with epi-β-amyrin (2), epitaraxerol (3), epi-a-amyrin (4), epilupeol (5), betulin (6), betulinic acid (7), lupenone (8), betulone (9), betulonic acid (10), (9Z,12Z,15Z)-2,3-dihydroxypropyl octadecatrienoate (11), and (9Z,12Z)-2,3-dihydroxypropyl octadecadienoate (12)were isolated from the stems of Excoecaria agallocha L. Their structures were elucidated by spectroscopic analyses, and the absolute stereochemistry of 1 was assigned using Mosher method. Compounds 4, 8, 10-12 were isolated from the genus Excoecaria for the first time.
文摘The characteristics of macrofauna communities in three mangrove assemblages [Avicennia marina+Acgiceras corniculatum (MC)community, A.corniculatum (C) community and Bruguiera gymnorrhiza+A.corniculatum (GC) community] were studied in Zhanjiang Mangrove Nature Reserves during 2005 and 2006. Of the three mangrove assemblages, the macrofauna species number, density, biomass, Richness index and Shannon-Wiener index were the highest, and the Simpson dominance index was medial at MC community. However the Pielou Evenness index of MC community was slightly lower than that at C community. At C community, the number of macrofauna species obviously reduced, especially infaunal, caving and adhering life forms, and the biomass and density were the lowest. Because of the even distribution of individuals of different species, the Simpson dominance index was the lowest and the evenness index was the highest. Although the Richness index at C community was slightly lower than that at MC community, the Shannon-Wiener index was near to that at MC community. At GC community, the number of macrofauna species, especially infaunal and caving life forms, continued to decrease comparing C community, but the biomass and density increased slightly. As the distribution of individuals of different species was uneven, the Simpson dominance index was the highest and the Pielou Evenness index was the lowest. Furthermore, the Richness index dropped to the lowest. The Shannon-Wiener index also dropped accordingly to the lowest. The dominant life forms of MC were infaunal and caving, while those of C and GC community were both caving. The ratio of the GS/GSB of macrofauna communities in the three mangrove assemblages were 0.48, 0.63 and 0.80, respectively. The community structures at the same mangrove assemblages were all quite similar, with those at GC community being most similar. However, there were obvious differences among the community structures at the three different mangrove assemblages. These results implied that the different mangrove assemblages had different affects on the macrofauna communities and shed light on the macrofauna adaptation capability to specific habitats.
文摘Leizhou Peninsula, located at southem end of mailand China, has 9 284.3 ha mangrove distributed more than 100 sites along its inlets and open coastlines. This paper presents the surveys on mangrove area in Leizhou Peninsula during 2000 and 2008, especially the survey in the eight major mangrove areas in 2002. The flora recorded in mangrove systems includes 69 large algea species, 13 native true mangrove species, nine native semi-mangrove species, and another seven intoduced true mangrove species with Sonneratia apetala as the quickest growing exotic mangrove species dominatant in the mangrove plantations, and more than 100 land flora species, consisting of 17 main mangrove associations. The plant biodiversity habitats remained mainly small patches and diverse, and were becoming worse under the intensive disturbance of human acitivities and coastal pollutions, which decreased the value of mangrove coasts as the important sites for flying-by migrating birds in Leizhou Peninsula. The effective mangrove conservation measures should be implemented.
基金Supported by Science Foundation of Guangxi Province (0899006)South China Agricultural University Principal Foundation ( 5100-k05099)~~
文摘[Objective] The aim was to identify the species diversity of Actinomycetes from Mangrove forest in Beihai,Guangxi Province. [Method] 10 strains of typical Actinomycetes were isolated from Mangrove forest soil,and the Actinomycetes genomic DNA was successful extracted. 16S rDNA was amplified by PCR and sequenced by Sanger dideoxy sequencing method. [Result] All the sequences were blasted in genbank,eight strains belonged to the genus of Streptomyces (80%),and two strains belonged to the genus of Nocardiopsis (20%). [Conclusion] There are many different Actinomycetes species in Mangrove forest soil samples in Beihai,Guangxi Province.
基金Supported by the National Basic Research Program (973 Program) of China (No. 2009CB421101)the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KSCX2-SW-132)the Guangdong Sci-Tech Planning Project(Nos. 2008A030203007 and 2010B060200039)
文摘Based on total carbon(C) and C isotopes in sediment cores,sedimentary organic carbon(SOC) was quantified in three types of mangrove sites(barren flat sites without mangroves,mangrove plantations,and natural mangrove forests),which were considered to represent a continuum from least restored to most restored sites in southern China.SOC densities in the barren sites,plantations,and natural forests were 90,170 and 288 Mg ha 1,respectively.We inferred that mangrove restoration increased SOC accumulation in coastal areas.At 0-70 cm depth,SOC δ 13 C values in both mangrove sites ranged from 27.37‰ to 23.07‰ and exhibited gradual enrichment with depth.In contrast,the values in the barren flat sites remained around 22.19‰ and fluctuated slightly with depth.At 0-60 cm,the 14 C ages of the SOC in the barren flat site,the natural mangrove site,and the artificial mangrove site ranged from 1 397 to 2 608,255 to 2 453,and 391 to 2 512 years BP,respectively.In both types of mangrove sites but not in the barren flat sites,the enrichment of δ 13 C with depth was related to increases in SOC decay and SOC age with depth.According to analysis of 14 C age,much of the mangrove-derived C was transported and stored at 0-60 cm depth under anaerobic conditions in both mangrove sites.The sediments of mangrove forests in southern China sequester large quantities of SOC during mangrove restoration.
文摘According to the survey of Guangdong mangrove resource in 2001 and authors field investigations in the past 5 years, the total mature mangrove land area of Guangdong Province was estimated at 9084 hm2, accounting for 41.4% of total mangrove land area of China. These mangrove forests totally consisted of 50 species belonging to 28 families, distributed at more than 100 locations along the coastlines of Guangdong and most of them present a high dense and dwarf appearance. The Ass. Avicennia marina is the most dominant mangrove association. The investigation results showed that the mangrove forests with coverage rates above 0.7 accounted for 68.0% of the total mangrove land area of the province and 77.8% of mangrove forests was less than 2 m in tree height. Since 1950, 54.6% of mangrove forests have disappeared due to paddy rice reclaim, aquaculture and city constructions. Derivational conservation efforts are still weakly empowered and should be strengthened intensively. The author suggested that mangrove laws and regulations should be enforced, mangrove scientific research should be strengthened; and mangrove conservation awareness of local community should be raised on conservation of mangroves.