The exotic saltmarsh cordgrass,Spartina alterniflora(Loisel)Peterson&Saarela,is one of the important causes for the extensive destruction of mangroves in China due to its invasive nature.The species has rapidly sp...The exotic saltmarsh cordgrass,Spartina alterniflora(Loisel)Peterson&Saarela,is one of the important causes for the extensive destruction of mangroves in China due to its invasive nature.The species has rapidly spread wildly across coastal wetlands,challenging resource managers for control of its further spread.An investigation of S.alterniflora invasion and associated ecological risk is urgent in China's coastal wetlands.In this study,an ecological risk invasive index system was developed based on the Driving Force-Pressure-State-Impact-Response framework.Predictions were made of'warning degrees':zero warning and light,moderate,strong,and extreme warning,by developing a back propagation(BP)artificial neural network model for coastal wetlands in eastern Fujian Province.Our results suggest that S.alterniflora mainly has invaded Kandelia candel beaches and farmlands with clustered distributions.An early warning indicator system assessed the ecological risk of the invasion and showed a ladder-like distribution from high to low extending from the urban area in the central inland region with changes spread to adjacent areas.Areas of light warning and extreme warning accounted for43%and 7%,respectively,suggesting the BP neural network model is reliable prediction of the ecological risk of S.alterniflora invasion.The model predicts that distribution pattern of this invasive species will change little in the next 10 years.However,the invaded patches will become relatively more concentrated without warning predicted.We suggest that human factors such as land use activities may partially determine changes in warning degree.Our results emphasize that an early warning system for S.alterniflora invasion in China's eastern coastal wetlands is significant,and comprehensive control measures are needed,particularly for K.candel beach.展开更多
Within the expanse of China’s coastline, the invasive alien cordgrass species Spartina alterniflora has caused profound nationwide damage and has emerged as a critical factor contributing to the degradation of mangro...Within the expanse of China’s coastline, the invasive alien cordgrass species Spartina alterniflora has caused profound nationwide damage and has emerged as a critical factor contributing to the degradation of mangrove wetlands, especially in the study area in Beihai, Guangxi. However, current treatments for S. alterniflora remain less effective and limited research focuses on the preliminary changes after artificial plantation. A comprehensive approach combining physical interventions with biological control measures has been employed to eradicate smooth cordgrass and facilitate the restoration of native mangrove wetlands. The study involved the periodic monitoring of the growth conditions of mangroves and the biodiversity of avian and benthic organisms, conducted at three to four-month intervals following the artificial plantation with one-year-old seedlings and propagules of native mangrove species Rhizophora stylosa. Results indicated that through the allometric equation, the above-ground biomass of planted seedlings had a ~20 g increase in average but the growth conditions were not significant over an eight-month period. High percentage of important avian species underlined the potential of the study site to serve as a worthwhile habitat and notable seasonal variations were observed in the biodiversity of bird species. Biodiversity indices of bird and benthos species also followed a similar fluctuation and reached a peak in April 2023. This research underscores the initial lack of distinct improvements during the early stages of the ecological restoration project, thorough maintenance, long-term monitoring, holistic considerations on a larger scale would be imperative for ongoing projects in the future.展开更多
Benthic macroinvertebrate communities in Spartina alterniflora zones in the Yangtze Estuary, in China, were investigated seasonally in 2005, and their structure and biodiversity were analyzed. Twenty-one species were ...Benthic macroinvertebrate communities in Spartina alterniflora zones in the Yangtze Estuary, in China, were investigated seasonally in 2005, and their structure and biodiversity were analyzed. Twenty-one species were identified, across four Classes; 10 species of Crustacea, five species of Polychaeta, five species of Gastropoda, and one species of Lamellibranchia. Dominant species included： Assiminea sp., Notomastus latericeus, Cerithidea largillierl, Gtauconome chinensi and Gammaridae sp. Functional groups were comprised of a phytophagous group and a detritivorous group. The average density of all benthic macroinvertebrates was 650.5 ±719.2 inds/m^2 in the survey area. The high value of the standard deviation of the average density was a result of abundant Assiminea sp. at Beihu tidal flats. The average density of macroinvertebrates from Beihu tidal flat, Chongming Dongtan to Jinshanwei tidal flat decreased gradually. There was significant difference between compositions and abundance of macroinvertebrates along the estuary gradient （P 〈 0.05）. The density and biodiversity were highest in summer and lowest in winter. The mean biomass of macroinvertebrates was 20.8 ± 6.1 g/m^2. Biomass changed seasonally in the same way as density, with the change in biomass being： summer （Aug.） 〉autumn （Oct.） 〉spring （Apr.） 〉 winter （Dec.）. A BIO-ENV analysis showed that the mean grain size of sediment, height of Spartina and salinity were the ma- jor factors which affected the structure of the macroinvertebrate community. Variations in the community structure were probably caused by the population dynamics of S. alterniflora along with the variation in sampling time and location.展开更多
互花米草(Spartina alterniflora属于禾本科米草属多年生单子叶草本植物,具有耐盐耐淹及其快速高效的生物质合成能力以及生物质能储量丰富的特点。自1979年引种到我国以来,在防风护沙、保滩护堤等方面发挥了积极的作用,同时也给沿海生...互花米草(Spartina alterniflora属于禾本科米草属多年生单子叶草本植物,具有耐盐耐淹及其快速高效的生物质合成能力以及生物质能储量丰富的特点。自1979年引种到我国以来,在防风护沙、保滩护堤等方面发挥了积极的作用,同时也给沿海生态系统带来了一定的影响,年国家环保总局将其列入首批外来入侵物种名单。本文根据文献报道简析了近年来国内外科学家对互花米草的研究成果。利用科学引文索引(Science Citation Index Expanded,SCI-E和德温特专利索引(Derwent Innova.tion Index,DII及Innography为数据源,采用Thomson Data AnalyzerTDA等数据库和分析软件对互花米草研究领域发表的文献和专利进行分析,简要阐述了近年来国际上对于互花米草的研发动态与综合利用情况。展开更多
[Objective] This study aimed to analyze the genetic structure of eight populations of Spartina alterniflora in China at the nuclear DNA level.[Method] The EH277045-derived sequences were amplified from 75 samples in 8...[Objective] This study aimed to analyze the genetic structure of eight populations of Spartina alterniflora in China at the nuclear DNA level.[Method] The EH277045-derived sequences were amplified from 75 samples in 8 populations and directly sequenced.Nucleotide diversity,haplotype diversity,the mean value of Nei＇s genetic distance,genetic differentiation index FST and other genetic parameters were calculated to estimate the genetic diversity and genetic differentiation of S.alterniflora populations in China.[Result] 75 samples were divided into 25 haplotypes by 28 polymorphic sites.Relatively high nucleotide diversity（π=0.011） and haplotype diversity（Hd=0.794） were detected.The mean value of Nei＇s genetic distance and genetic differentiation index FST among eight populations were 0.056 and 0.222,respectively,the Nei＇s genetic distance ranged from 0.000 to 0.189 and FST ranged from 0.000 to 0.444 between each pair of the eight populations.AMOVA result revealed that 79% and 21% of the total genetic variation was partitioned within and among S.alterniflora populations,respectively.[Conclusion] At the nuclear DNA level,there were a relatively high level of genetic diversity and a relatively low level of genetic differentiation among S.alterniflora populations in China,and the genetic diversity existed mainly within rather than among populations.展开更多
The tidal flats of the Wanggang area, on the Jiangsu coast, represent the largest continuously distributed coastal wetland in terms of area coverage in China, and the dynamics of tidal flat accretion and erosion is hi...The tidal flats of the Wanggang area, on the Jiangsu coast, represent the largest continuously distributed coastal wetland in terms of area coverage in China, and the dynamics of tidal flat accretion and erosion is highly complicated. The cord-grass Spartina alterniflora, which was introduced artificially into the Jiangsu coast, has significant influences on the regional tidal flat evolution in terms of deposition rate, spacial sediment distribution patterns and tidal creek morphology. On the basis of the data set of bed elevation and accumulation rate for different periods of time, the applicability of the Pethick - Allen model to the Jiangsu tidal salt marshes is discussed. In addition, caesium-137 dating was carried out for sediment samples collected from the salt marsh of the Wangang area. In combination with the caesium-137 analysis and the data collected from literature, the Pethick - Allen model was used to derive the accumulation rate in the Wanggang tidal flat for the various periods. The results show that the pattern of tidal flat accretion has been modified, due to more rapid accretion following the iatroduction of S. alterniflora to the region. Surficial sediment samples were collected from representative profiles and analyzed for grain size with a laser particle analyzer. The result shows that fine-grained sediment has been trapped by the plant, with most of the sediment deposited on the Suaeda salsa and Spartina angelica flats being derived from drainage creeks rather than the from gently sloping tidal flats. Remote sensing analysis and in situ observations indicate that the creeks formed in the S. alterniflora flat have a relatively small ratio of width to depth, a relatively high density, and are more stable than the other tidal flat creek systems in the study area.展开更多
Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in China almost 30 years ago and has become an urgent topic due to its invasiveness i...Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in China almost 30 years ago and has become an urgent topic due to its invasiveness in the coastal zone of China. The impacts of this alien species S. alterniflora on intertidal ecosystem processes in the Jiangsu coastland were investigated by comparing the sediment nutrient availability and trace element concentration characteristics in a mud flat and those of a four-year old Spartina salt marsh that had earlier been a mudflat. At each study site, fifteen plots were sampled in different seasons to determine the sediment characteristics along the tidal flats. The results suggested that Spartina salt marsh sediments had significantly higher total N, available P, and water content, but lower pH and bulk density than mudflat sediments. Sediment salinity, water content, total N, organic C, and available P decreased along a seaward gradient in the Spartina salt marsh and increased with vegetation biomass. Furthermore, the concentrations of trace elements and some metal elements in the sediment were higher under Spartina although these increases were not significant. Also, in the Spartina marsh, some heavy metals were concentrated in the surface layer of the sediment. The Spartina salt marsh in this study was only four years old; therefore, it is suggested that further study of this allen species on a longer time frame in the Jiangsu coastland should be carried out.展开更多
基金funded by Forestry Peak Discipline Construction Project of Fujian Agriculture and Forestry University (72202200205)Fujian Province Natural Science (2022J01575)Science and Technology Innovation Project of Fujian Agriculture and Forestry University (KFA20036A)。
文摘The exotic saltmarsh cordgrass,Spartina alterniflora(Loisel)Peterson&Saarela,is one of the important causes for the extensive destruction of mangroves in China due to its invasive nature.The species has rapidly spread wildly across coastal wetlands,challenging resource managers for control of its further spread.An investigation of S.alterniflora invasion and associated ecological risk is urgent in China's coastal wetlands.In this study,an ecological risk invasive index system was developed based on the Driving Force-Pressure-State-Impact-Response framework.Predictions were made of'warning degrees':zero warning and light,moderate,strong,and extreme warning,by developing a back propagation(BP)artificial neural network model for coastal wetlands in eastern Fujian Province.Our results suggest that S.alterniflora mainly has invaded Kandelia candel beaches and farmlands with clustered distributions.An early warning indicator system assessed the ecological risk of the invasion and showed a ladder-like distribution from high to low extending from the urban area in the central inland region with changes spread to adjacent areas.Areas of light warning and extreme warning accounted for43%and 7%,respectively,suggesting the BP neural network model is reliable prediction of the ecological risk of S.alterniflora invasion.The model predicts that distribution pattern of this invasive species will change little in the next 10 years.However,the invaded patches will become relatively more concentrated without warning predicted.We suggest that human factors such as land use activities may partially determine changes in warning degree.Our results emphasize that an early warning system for S.alterniflora invasion in China's eastern coastal wetlands is significant,and comprehensive control measures are needed,particularly for K.candel beach.
文摘Within the expanse of China’s coastline, the invasive alien cordgrass species Spartina alterniflora has caused profound nationwide damage and has emerged as a critical factor contributing to the degradation of mangrove wetlands, especially in the study area in Beihai, Guangxi. However, current treatments for S. alterniflora remain less effective and limited research focuses on the preliminary changes after artificial plantation. A comprehensive approach combining physical interventions with biological control measures has been employed to eradicate smooth cordgrass and facilitate the restoration of native mangrove wetlands. The study involved the periodic monitoring of the growth conditions of mangroves and the biodiversity of avian and benthic organisms, conducted at three to four-month intervals following the artificial plantation with one-year-old seedlings and propagules of native mangrove species Rhizophora stylosa. Results indicated that through the allometric equation, the above-ground biomass of planted seedlings had a ~20 g increase in average but the growth conditions were not significant over an eight-month period. High percentage of important avian species underlined the potential of the study site to serve as a worthwhile habitat and notable seasonal variations were observed in the biodiversity of bird species. Biodiversity indices of bird and benthos species also followed a similar fluctuation and reached a peak in April 2023. This research underscores the initial lack of distinct improvements during the early stages of the ecological restoration project, thorough maintenance, long-term monitoring, holistic considerations on a larger scale would be imperative for ongoing projects in the future.
文摘Benthic macroinvertebrate communities in Spartina alterniflora zones in the Yangtze Estuary, in China, were investigated seasonally in 2005, and their structure and biodiversity were analyzed. Twenty-one species were identified, across four Classes; 10 species of Crustacea, five species of Polychaeta, five species of Gastropoda, and one species of Lamellibranchia. Dominant species included： Assiminea sp., Notomastus latericeus, Cerithidea largillierl, Gtauconome chinensi and Gammaridae sp. Functional groups were comprised of a phytophagous group and a detritivorous group. The average density of all benthic macroinvertebrates was 650.5 ±719.2 inds/m^2 in the survey area. The high value of the standard deviation of the average density was a result of abundant Assiminea sp. at Beihu tidal flats. The average density of macroinvertebrates from Beihu tidal flat, Chongming Dongtan to Jinshanwei tidal flat decreased gradually. There was significant difference between compositions and abundance of macroinvertebrates along the estuary gradient （P 〈 0.05）. The density and biodiversity were highest in summer and lowest in winter. The mean biomass of macroinvertebrates was 20.8 ± 6.1 g/m^2. Biomass changed seasonally in the same way as density, with the change in biomass being： summer （Aug.） 〉autumn （Oct.） 〉spring （Apr.） 〉 winter （Dec.）. A BIO-ENV analysis showed that the mean grain size of sediment, height of Spartina and salinity were the ma- jor factors which affected the structure of the macroinvertebrate community. Variations in the community structure were probably caused by the population dynamics of S. alterniflora along with the variation in sampling time and location.
文摘互花米草(Spartina alterniflora属于禾本科米草属多年生单子叶草本植物,具有耐盐耐淹及其快速高效的生物质合成能力以及生物质能储量丰富的特点。自1979年引种到我国以来,在防风护沙、保滩护堤等方面发挥了积极的作用,同时也给沿海生态系统带来了一定的影响,年国家环保总局将其列入首批外来入侵物种名单。本文根据文献报道简析了近年来国内外科学家对互花米草的研究成果。利用科学引文索引(Science Citation Index Expanded,SCI-E和德温特专利索引(Derwent Innova.tion Index,DII及Innography为数据源,采用Thomson Data AnalyzerTDA等数据库和分析软件对互花米草研究领域发表的文献和专利进行分析,简要阐述了近年来国际上对于互花米草的研发动态与综合利用情况。
基金Supported by National Natural Science Foundation of China(30900161)~~
文摘[Objective] This study aimed to analyze the genetic structure of eight populations of Spartina alterniflora in China at the nuclear DNA level.[Method] The EH277045-derived sequences were amplified from 75 samples in 8 populations and directly sequenced.Nucleotide diversity,haplotype diversity,the mean value of Nei＇s genetic distance,genetic differentiation index FST and other genetic parameters were calculated to estimate the genetic diversity and genetic differentiation of S.alterniflora populations in China.[Result] 75 samples were divided into 25 haplotypes by 28 polymorphic sites.Relatively high nucleotide diversity（π=0.011） and haplotype diversity（Hd=0.794） were detected.The mean value of Nei＇s genetic distance and genetic differentiation index FST among eight populations were 0.056 and 0.222,respectively,the Nei＇s genetic distance ranged from 0.000 to 0.189 and FST ranged from 0.000 to 0.444 between each pair of the eight populations.AMOVA result revealed that 79% and 21% of the total genetic variation was partitioned within and among S.alterniflora populations,respectively.[Conclusion] At the nuclear DNA level,there were a relatively high level of genetic diversity and a relatively low level of genetic differentiation among S.alterniflora populations in China,and the genetic diversity existed mainly within rather than among populations.
基金supported financially by the National Natural Science Foundation of China under contract Nos 40231010 and 40476041the Marine Science Youth Fund of State 0ceanic Administration of China under contract No.2006312.
文摘The tidal flats of the Wanggang area, on the Jiangsu coast, represent the largest continuously distributed coastal wetland in terms of area coverage in China, and the dynamics of tidal flat accretion and erosion is highly complicated. The cord-grass Spartina alterniflora, which was introduced artificially into the Jiangsu coast, has significant influences on the regional tidal flat evolution in terms of deposition rate, spacial sediment distribution patterns and tidal creek morphology. On the basis of the data set of bed elevation and accumulation rate for different periods of time, the applicability of the Pethick - Allen model to the Jiangsu tidal salt marshes is discussed. In addition, caesium-137 dating was carried out for sediment samples collected from the salt marsh of the Wangang area. In combination with the caesium-137 analysis and the data collected from literature, the Pethick - Allen model was used to derive the accumulation rate in the Wanggang tidal flat for the various periods. The results show that the pattern of tidal flat accretion has been modified, due to more rapid accretion following the iatroduction of S. alterniflora to the region. Surficial sediment samples were collected from representative profiles and analyzed for grain size with a laser particle analyzer. The result shows that fine-grained sediment has been trapped by the plant, with most of the sediment deposited on the Suaeda salsa and Spartina angelica flats being derived from drainage creeks rather than the from gently sloping tidal flats. Remote sensing analysis and in situ observations indicate that the creeks formed in the S. alterniflora flat have a relatively small ratio of width to depth, a relatively high density, and are more stable than the other tidal flat creek systems in the study area.
基金Project supported by the Natural Science Foundation of Jiangsu Province (No.JSNSF 20050307)the National Natural Science Foundation of China (No.NSFC 30470326).
文摘Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in China almost 30 years ago and has become an urgent topic due to its invasiveness in the coastal zone of China. The impacts of this alien species S. alterniflora on intertidal ecosystem processes in the Jiangsu coastland were investigated by comparing the sediment nutrient availability and trace element concentration characteristics in a mud flat and those of a four-year old Spartina salt marsh that had earlier been a mudflat. At each study site, fifteen plots were sampled in different seasons to determine the sediment characteristics along the tidal flats. The results suggested that Spartina salt marsh sediments had significantly higher total N, available P, and water content, but lower pH and bulk density than mudflat sediments. Sediment salinity, water content, total N, organic C, and available P decreased along a seaward gradient in the Spartina salt marsh and increased with vegetation biomass. Furthermore, the concentrations of trace elements and some metal elements in the sediment were higher under Spartina although these increases were not significant. Also, in the Spartina marsh, some heavy metals were concentrated in the surface layer of the sediment. The Spartina salt marsh in this study was only four years old; therefore, it is suggested that further study of this allen species on a longer time frame in the Jiangsu coastland should be carried out.
