The Community Structure of Benthic Macroinvertebrates Associated with Spartina alterniflora in the Yangtze Estuary, in China

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.

Analysis on Genetic Structure of Spartina alterniflora Populations in China Based on EH277045-derived Sequence

[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.

江苏沿海互花米草(Spartina alterniflora)盐沼的形成过程

选取江苏沿海的3个典型岸段,在2000—2001年进行了野外地貌沉积及植被调查,并进行了地形高程测量;选用了1985—2001年间7个时相的TM卫星影像资料,追踪了江苏互花米草盐沼形成的过程。结果表明,在移栽后的5—6年内,互花米草植被扩散缓慢,主要为立地扎根,走茎蔓延。在TM影像可以计量的规模上,互花米草植被在裸滩上的扩散可以分为三个阶段第一阶段为1993—1996年,随着面积逐渐增大,草仔数量明显增加,年扩展率逐渐扩大,到1996年,平均年扩展率已达30%。第二阶段为1996—1999年的3年间,互花米草人工盐沼的面积迅速扩大,年扩展率平均为43%。第三阶段为1999年以后,平均年扩展率迅速减小,为10%,预计还要减缓,最后,待原有潮滩生态位长满后,与滩涂自然淤长速率相应。

刈割与水位调节集成技术控制互花米草(Spartina alterniflora)

治理和控制外来物种互花米草(Spartina alterniflora)对维护崇明东滩自然保护区生物多样性具有重要的意义和必要性。研究在上海崇明东滩鸟类国家级自然保护区建立的受损滩涂湿地生态修复示范样地中开展"刈割与水位调节集成技术"治理互花米草的物理控制实验,以期寻求有效治理互花米草的控制技术。示范研究结果表明,单一的水位调节方法虽然可以降低互花米草群落的密度和叶面积指数(LAI),但至水淹处理100d后,处理样区内互花米草的生长和生物量已与对照区无显著差异。单一的水位调节方法不能达到有效快速控制互花米草的效果。通过在互花米草生长关键期(7月的扬花期)刈割+水位调节集成技术处理后,互花米草地上部分无再新生现象,至当年10月份(生长季末期),样区内互花米草的地上部分和地下部分已完全死亡并开始腐烂,达到了有效控制互花米草的效果。因此,应用刈割+水位调节集成技术治理互花米草,必须选择关键季节刈割互花米草地上部分,同时配合一定水位的持续淹水(约3个月),才能有效发挥其迅速有效治理互花米草的效果。扬花期刈割+水位调节集成技术可为沿海地区大范围防治互花米草扩散提供有效途径。

米草属植物Spartina angilica和Spartina alterniflora引种后江苏海岸湿地生态演化的初步探讨

选取江苏王港潮滩的盐蒿滩、大米草滩及互花米草滩,分析这三类滩面的地面以上生物量、初级生产力、动物洞穴参数和沉积物粒度,探讨大米草和互花米草引种区的湿地生态系统相对于盐蒿滩的变化。分析结果表明,互花米草滩的生物量远大于盐蒿滩和大米草滩;单位面积上动物洞穴数量相近,但洞穴大小有一定差异,互花米草滩动物洞穴稍大,数量也相对较多,这可能与初级生产力的提高有关。表层底质的粒径以互花米草滩为最细,盐蒿滩最粗,这种分布状况与互花米草引种前不同,说明互花米草促进了细颗粒物质的堆积。互花米草的引种在江苏海岸具有促淤和提高初级生产力的作用,而它对湿地生态系统的结构和功能的影响需要进一步研究。

盐和温度胁迫对外来种互花米草(Spartina alterniflora)生理生态特性的影响

盐浓度和环境温度是影响外来种互花米草自然分布的两大重要生态因子。在不同NaCl浓度和温度胁迫条件下,对互花米草幼苗根部和叶片中膜脂过氧化产物丙二醛(MDA)、游离脯氨酸及可溶性糖、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)的动态变化进行了测定。结果表明:当NaCl浓度低于100mmol·L-1时,可以促进互花米草的生长;而NaCl浓度超过100mmol·L-1时,互花米草可以通过提高体内保护酶(SOD、POD、CAT)活性,增加可溶性糖和游离脯氨酸含量来适应外界盐浓度变化;温度胁迫后,互花米草地上和地下器官对胁迫的响应程度不同,叶片中可溶性糖含量、CAT活性明显比根部高,而根部SOD、POD活性比叶片中高。

互花米草(Spartina alterniflora L.)对重金属Cd胁迫的生理响应

以盐生植物互花米草幼苗为试材,研究了其抗氧化酶体系活性（超氧化物歧化酶,SOD;过氧化物酶,POX;过氧化氢酶,CAT）对不同浓度Cd胁迫的响应变化,并利用非变性聚丙烯酰胺凝胶电泳对SOD及CAT进行了同工酶分析.结果表明,抗氧化酶活性与Cd处理浓度关系密切,0.1-2.0 mmol/L Cd浓度范围内SOD活性显著增加;POX活性在Cd浓度较低时相对稳定,高浓度下降低显著;而CAT酶活性在Cd浓度较高时被诱导升高.SOD同工酶谱受到Cd胁迫的显著影响,4.0 mmol/L处理下酶活性明显降低.CAT同工酶活性呈现先降后升的变化趋势,与酶总活性的检测结果基本一致.表明互花米草对重金属Cd具有一定程度的耐受性,可以通过提高酶促过氧化体系活性来应答Cd导致的氧化胁迫;而Cd浓度超过一定阈值后（4.0 mmol/L）,互花米草即遭受较严重的不可逆损伤.

互花米草(Spartina alterniflora)草场土壤微生物生态分布及某些酶活性的研究

种植互花米草的盐沼土中,细菌、放线菌和真菌的数量比对照盐沼土中多。就不同深度来说,15—30厘米土层中,细菌数最多。细菌总数的增减趋势是:夏秋两季最多,冬春两季较少。在各生理类群中,氨化细菌占优势;固氮细菌、硝化细菌次之;反硝化细菌和硫酸盆还原细菌最少。内源呼吸作用强度、添加葡萄糖后的呼吸作用强度、氧化丙酮酸的能力和氧化多酚化合物的能力皆显示出同样的趋势,即三年生草场土壤中生物活性最强,光滩土壤中生物活性最弱。在光滩土壤中,脲酶和过氧化氢酶活性很低,而种植互花米草的土壤中这两种酶活性较强,但与种植年限和季节变化无显著相关性。

简析互花米草(Spartina alterniflora的研发态势与综合利用

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。

磁场对互花米草(Spartina alterniflora)三种生态型的生理效应

磁场对互花米草具有显著的生理影响,通过三种生态型互花米草在芽、苗期过氧化物酶(POD)、细胞色素氧化酶(COD)、苹果酸脱氢酶(MDH)、酯酶(Esterase)等同工酶、游离氨基酸和种子发芽状况的分析,表明四种同工酶、氨基酸代谢和种子萌发明显受磁场的影响。不同的植物发育期,磁场影响不相同;四种同工酶对磁场的感应强度并不相同,磁场作用具有阈值,特定的磁场强度具有特定的生物效应,而不同的生态型,磁场阈值不同,故基因型不同是磁场生物效应差异的一个重要因素,在磁场诱变育种等生产实践和其他有关研究中应注意基因型的差异。

Effect of an Alien Species Spartina alterniflora Loisel on Biogeochemical Processes of Intertidal Ecosystem in the Jiangsu Coastal Region,China

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.

Impact of the cord-grass Spartina alterniflora on sedimentary and morphological evolution of tidal salt marshes on the Jiangsu coast,China

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.

外来入侵物种互花米草(Spartina alterniflora)及凤眼莲(Eichhornia crassipes)的遥感监测研究进展

外来物种的入侵给生态系统带来了许多正面的和负面的影响,并已成为当前学术界关注的热点问题之一。为了有效地管理以及合理地开发利用外来入侵物种,变害为利,需要对其种群的空间分布和动态变化进行监测。然而由于沿海滩涂和水体表面特殊的自然地理环境,使得传统的实地调查较为困难。3S技术是近年来发展起来的,从较大尺度定量研究滩涂植被互花米草(Spartina alterniflora)或水生植被凤眼莲(Eichhornia crassipes)的一种有效手段。研究人员通过收集不同时相的遥感影像,运用遥感处理软件对其进行分类解译,并结合GPS的野外核实修正,最后在GIS中对解译结果进行数据合成,即可统计出滩涂及水生植被的空间分布及动态变化。国内外的研究表明,3S技术可应用于外来入侵物种的动态监测,进而为入侵物种的控制与管理提供科学依据。但由于海岸带地区空间尺度相对较小,水生植物的空间分布变化比较剧烈,植被群落交错地带存在着混合像元,使得这一方法的分类精度具有一定的局限性,还需要进一步的研究和改进。

Responses of CH_4 Emissions to Nitrogen Addition and Spartina alterniflora Invasion in Minjiang River Estuary, Southeast of China

The nitrogen （N） input and Spartina alterniflora invasion in the tidal marsh of the southeast of China are increasingly serious. To evaluate CH4 emissions in the tidal marsh as affected by the N inputs and S. alterniflora invasion, we measured CH4 emissions from plots with vegetated S. alterniflora and native Cyperus malaccensis, and fertilized with exogenous N at the rate of 0 （NO）, 21 （N1） and 42 （N2） g N/（m2.yr）, respectively, in the Shanyutan marsh in the Minjiang River estuary, the southeast of China. The average CH4 fluxes during the experiment in the C. malaccensis and S. alterniflora plots without N addition were 3.67 mg CHa/（m2.h） and 7.79 mg CH4/（m2-h）, respectively, suggesting that the invasion of S. alterniflora into the Minjiang River estuary stimulated CH4 emission. Exogenous N had positive effects on CH4 fluxes both in native and in invaded tidal marsh. The mean CH4 fluxes of NI and N2 treat- ments increased by 31.05% and 123.50% in the C. malaccensis marsh, and 63.88% and 7.55% in the S. alterniflora marsh, respectively, compared to that of NO treatment. The CH4 fluxes in the two marshes were positively correlated with temperature and pH, and nega- tively correlated with electrical conductivity and redox potential （Eh） at different N addition treatments. While the relationships between CH4 fluxes and environmental variables （especially soil temperature, pH and Eh at different depths） tended to decrease with N additions. Significant temporal variability in CH4 fluxes were observed as the N was gradually added to the native and invaded marshes. In order to better assess the global climatic role of tidal marshes as affected by N addition, much more attention should be paid to the short-term temporal variability in CH4 emission.

Geographical Variation and Influencing Factors of Spartina alterniflora Expansion Rate in Coastal China

Biological invasion poses a huge threat to ecological security.Spartina alterniflora was introduced into China in 1979,and its arrival corresponded with negative effects on native ecosystems.To explore geographical variation of its expansion rate in coastal China,we selected 43 S.alterniflora sites from Tianjin Coastal New Area to Beihai.The area expansion rate,expansion rate paralleling and vertical to the shoreline were analysed based on Landsat images and field survey in 2015.Simple Ocean Data Assimilation(SODA)and climate data were collected to statistically analyse the influential factors of expansion rate.Results showed that significant difference of S.alterniflora area expansion rate among different latitude zones(P<0.01),increasing from 6.08%at southern(21°N–23°N)to 19.87% in Bohai Bay(37°N–39°N)along latitude gradient.There was a significant difference in expansion rate vertical to shoreline in different latitude zones(P<0.01)with the largest occurring in Bohai Bay(256m/yr,37°N–39°N),and showed an decreasing tendency gradually from north to south.No significant difference and latitudinal clines in expansion rate paralleling to shoreline were observed.Expansion rate had significant negative correlation with mean seawater temperature,the lowest seawater temperature,current zonal velocity and meridional velocity and presented a reducing trend as these biotic factors increased;however,they were not significantly correlated with the highest seawater temperature and mean seawater salinity.We identified significant correlations between expansion rate and annual mean temperature,the lowest temperature in January and annual precipitation,but there was little correlation with annual diurnal difference in temperature and the highest temperature in July.The rapid expansion rate in high-latitude China demonstrated a higher risk of potential invasion in the north;dynamic monitoring and control management should be established as soon as possible.

互花米草(Spartina alterniflora)潜在分布格局的空间尺度效应

了解不同空间尺度下外来入侵植物互花米草(Spartina alterniflora)的潜在分布格局,有助于制定科学的防治管理策略,维护滨海湿地的生物多样性。研究基于有效的地理分布点位和环境变量数据集,设置了3个研究区幅度(区域、国家、全球)和5种环境变量粒度(30″、1.0′、2.5′、5.0′、10′),应用最大熵(MaxEnt)模型预测互花米草在不同幅度和粒度下的潜在分布,探究互花米草分布格局及其环境影响因子对空间尺度响应。结果表明:(1)MaxEnt模型在不同空间尺度下的预测效果较好,各尺度下测试集的受试者曲线下面积(AUC)值均大于0.8,真实技巧统计值(TSS)值则超过0.56,但模型的预测精度对空间尺度变化较为敏感;(2)不同空间尺度下互花米草的潜在分布格局存在着显著的差异性,表现为适生区面积会随着空间范围扩大或环境变量分辨率降低而提高,且质心位置也在不断发生地带性转移;(3)空间尺度的变化会削弱主要环境变量的解释力。在大尺度范围和低分辨率环境变量图层中,气候因子的重要性较大,而在相反尺度下地形因子的影响度得到提升;(4)研究区范围与环境变量分辨率不匹配时,模型预测精度和物种分布格局会产生显著的变化,建议在区域范围中,采用空间分辨率1.0′以下的环境变量来预测互花米草的潜在分布格局。

Distribution and invasion of Spartina alterniflora within the Jiaozhou Bay monitored by remote sensing image

Spartina alterniflora as an alien invasive plant,poses a serious threat to the ecological functions of the coastal wetland of the Jiaozhou Bay.As of 2019,the distribution area of S.alterniflora in the Jiaozhou Bay has reached more than 500 hm^(2).For this reason,combined with field surveys,remote sensing monitoring of the invasion S.alterniflora in the Jiaozhou Bay has been carried out.To accurately identify S.alterniflora within the Jiaozhou Bay coastal wetland,we used a new method which is an implement of deep convolutional neural network,and by which we got a higher accuracy than the traditional method.Based on distribution of S.alterniflora extracted by the proposed method,the temporal and spatial distribution characteristics of S.alterniflora were analyzed.And then combined with environmental factors,the invasion mechanism of S.alterniflora in the Jiaozhou Bay was analyzed in detail.From the monitoring results,it can be seen that S.alterniflora in Jiaozhou Bay is mainly distributed in the beaches near the Yanghe River Estuary and its southern side,the Dagu River Estuary and the Nügukou.Spartina alterniflora first broke out near the Yanghe River Estuary and gradually spread to the tidal flats near the Nügukou.The Dagu River Estuary is dominated by S.anglica,whose area has not changed much over the years,and a small amount of S.alterniflora has invaded later.

Soil Organic Carbon Contents and Stocks in Coastal Salt Marshes with Spartina alterniflora Following an Invasion Chronosequence in the Yellow River Delta,China

Plant invasion alters the fundamental structure and function of native ecosystems by affecting the biogeochemical pools and fluxes of materials and energy. Native(Suaeda salsa) and invasive(Spartina alterniflora) salt marshes were selected to study the effects of Spartina alterniflora invasion on soil organic carbon(SOC) contents and stocks in the Yellow River Delta. Results showed that the SOC contents(g/kg) and stocks(kg/m^2) were significantly increased(P < 0.05) after Spartina alterniflora invasion of seven years, especially for the surface soil layer(0–20 cm). The SOC contents exhibited an even distribution along the soil profiles in native salt marshes, while the SOC contents were gradually decreased with depth after Spartina alterniflora invasion of seven years. The natural ln response ratios(Ln RR) were applied to identify the effects of short-term Spartina alterniflora invasion on the SOC stocks. We also found that Spartina alterniflora invasion might cause soil organic carbon losses in a short-term phase(2–4 years in this study) due to the negative Ln RR values, especially for 20–60 cm depth. And the SOCD in surface layer(0–20 cm) do not increase linearly with the invasive age. Spearman correlation analysis revealed that silt + clay content was exponentially related with SOC in surface layer(Adjusted R^2 = 0.43, P < 0.001), suggesting that soil texture could play a key role in SOC sequestration of coastal salt marshes.

Influence of Artificial Cofferdam and Spartina alterniflora Expansion on Evolution of Suaeda salsa Marsh in Yancheng Coastal Wetland of East China

Suaeda salsa is an important local species in the intertidal beach of the Western Pacific coast. However,under the artificial cofferdam and Spartina alterniflora expansion,Suaeda marsh has degraded seriously. Therefore,using Yancheng Nature Reserve as a case study area,taking ETM+images in 2000,2006 and 2011 as the basic data sources,we revealed the evolution characteristics of Salsa marsh which was impacted. The research results are as follows. From 2000 to 2011,Salsa marsh area in the artificial area tempestuously degraded,decreasing by 87. 158%,more than 22% than those in the natural area. The landscape was fragmentized. Landscape polymerization degree index dropped from 95. 780 to 65. 455,more than 16% than those in the natural area. The mean patch area fell down to 21. 429 ha from 389. 333 ha,more than 11% that in the natural area. Compared to the steady change in natural conditions,the area was reduced by 118. 167 ha/a from 2000 to 2006,while during 2006-2011,it was only 51. 500 ha/a in artificial area. As for spatial change of landscape,in artificial area,the Salsa marsh centroid moved forward to the southeast with 666. 350 m,but that in natural area moved forward to the north with 1 042. 710 m from 2000 to 2006. From 2006 to 2011,the centroid moved forward to east and north respectively. Artificial cofferdam transformed the area into freshwater ecosystem,and meanwhile the freshwater was beneficial to Reed marsh. During 2000 to 2006,in the artificial area,539 ha Salsa marsh controlled by cofferdam transferred into reed marsh and aquaculture ponds,of which the transformation rate was nearly 4% higher than that in natural area. From 2006 to 2011,178 ha Salsa marsh was transferred into reed marsh,the transformation rate was 20% higher than that in natural area. With rapid spreading and strong competition of Spartina species,the coastal wetland has formed the pattern of " Salsa – Spartina marshes". From 2000 to 2006,in artificial area,15. 24% of Salsa marsh was transferred into Spartina marsh,of which the transformation rate was13% higher than that in natural area. And from 2006 to 2011,30. 07% Salsa marsh was replaced by the Spartina marsh in artificial area,the rate was almost 10% higher than that in the natural area.

Impacts of Expansion of Spartina alterniflora on Yancheng Tidal Flat Wetland in Jiangsu Province of China

Based on 4 phases of Thematic Mapper(TM) images of the Core Area of Yancheng National Nature Reserve in Jiangsu Province of China in 1996,2002,2006 and 2010,this paper analyzed the temporal and spatial changes in Spartina alterniflora landscape and the corresponding impacts on coastal wetlands in combination with Remote Sensing(RS) and Geographical Information System(GIS) technologies. The methods of field survey,transfer matrix,landscape diversity indicators and mass center were applied. The results indicated that:(1) S. alterniflora expansion brought about obvious changes in wetland landscape composition and structure,which seriously influenced the evolution process of wetland landscapes.(2) The transition rates of S. alterniflora marsh area were different dramatically in four periods.(3) The expansion of S. alterniflora promoted the siltation in tidal mudflat. It led to increase of the elevation and outward expansion of land. Understanding the temporal and spatial pattern of S. alterniflora is favorable for preservation,utilization and management of wetlands with S. alterniflora and the other coastal wetland landscapes.