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 va...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.展开更多
The rapid invasion of the plant Spartina alterniflora in coastal wetland areas can threaten the capacity of their soils to store carbon(C),nitrogen(N),and sulfur(S).In this study,we investigated the spatial and tempor...The rapid invasion of the plant Spartina alterniflora in coastal wetland areas can threaten the capacity of their soils to store carbon(C),nitrogen(N),and sulfur(S).In this study,we investigated the spatial and temporal distribution patterns of C,N and S of both soil and(native and invasive)plants in four typical coastal wetlands in the core area of the Yancheng National Nature Reserve,China.The results show that the invasive S.alterniflora greatly influenced soil properties and increased soil C,N and S storage capacity:the stock(mean±standard error)of soil organic carbon(SOC,(3.56±0.36)kg/m^3),total nitrogen(TN,(0.43±0.02)kg/m^3),and total sulfur(TS,(0.69±0.11)kg/m^3)in the S.alterniflora marsh exceeded those in the adjacent bare mudflat,Suaeda salsa marsh,and Phragmites australis marsh.Because of its greater biomass,plant C((1193.7±133.6)g/m^2),N((18.8±2.4)g/m^2),and S((9.4±1.5)g/m^2)storage of S.alterniflora was also larger than those of co-occurring native plants.More biogenic elements circulated in the soil-plant system of the S.alterniflora marsh,and their spatial and temporal distribution patterns were also changed by the S.alterniflora invasion.Soil properties changed by S.alterniflora’s invasion thereby indirectly affected the accumulation of soil C,N and S in this wetland ecosystem.The SOC,TN,and TS contents were positively correlated with soil electrical conductivity and moisture,but negatively correlated with the pH and bulk density of soil.Together,these results indicate that S.alterniflora invasion altered ecosystem processes,resulted in changes in net primary production and litter decomposition,and increased the soil C,N and S storage capacity in the invaded ecosystems in comparison to those with native tallgrass communities in the coastal wetlands of East China.展开更多
基金Under the auspices of Special Foundation for State Major Basic Research Program of China(No.2013FY111800,2013FY111100-02)
文摘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.
基金Under the auspices of National Basic Research Program of China(No.2012CB956100)National Natural Science Foundation of China(No.41301085).
文摘The rapid invasion of the plant Spartina alterniflora in coastal wetland areas can threaten the capacity of their soils to store carbon(C),nitrogen(N),and sulfur(S).In this study,we investigated the spatial and temporal distribution patterns of C,N and S of both soil and(native and invasive)plants in four typical coastal wetlands in the core area of the Yancheng National Nature Reserve,China.The results show that the invasive S.alterniflora greatly influenced soil properties and increased soil C,N and S storage capacity:the stock(mean±standard error)of soil organic carbon(SOC,(3.56±0.36)kg/m^3),total nitrogen(TN,(0.43±0.02)kg/m^3),and total sulfur(TS,(0.69±0.11)kg/m^3)in the S.alterniflora marsh exceeded those in the adjacent bare mudflat,Suaeda salsa marsh,and Phragmites australis marsh.Because of its greater biomass,plant C((1193.7±133.6)g/m^2),N((18.8±2.4)g/m^2),and S((9.4±1.5)g/m^2)storage of S.alterniflora was also larger than those of co-occurring native plants.More biogenic elements circulated in the soil-plant system of the S.alterniflora marsh,and their spatial and temporal distribution patterns were also changed by the S.alterniflora invasion.Soil properties changed by S.alterniflora’s invasion thereby indirectly affected the accumulation of soil C,N and S in this wetland ecosystem.The SOC,TN,and TS contents were positively correlated with soil electrical conductivity and moisture,but negatively correlated with the pH and bulk density of soil.Together,these results indicate that S.alterniflora invasion altered ecosystem processes,resulted in changes in net primary production and litter decomposition,and increased the soil C,N and S storage capacity in the invaded ecosystems in comparison to those with native tallgrass communities in the coastal wetlands of East China.