To determine the potential impacts of exogenous nitrogen(N)enrichment on distribution and transfer of N in Suaeda salsa marsh in the Yellow River Estuary,the variations of N in plant-soil system during the growing sea...To determine the potential impacts of exogenous nitrogen(N)enrichment on distribution and transfer of N in Suaeda salsa marsh in the Yellow River Estuary,the variations of N in plant-soil system during the growing season were investigated by field N addition experiment.The experiment included four treatments:NN(no N input treatment,0gNm^(−2) yr^(−1)),LN(low N input treatment,3.0 gNm^(−2) yr^(−1)),MN(medium N input treatment,6 gNm^(−2) yr^(−1))and HN(high N input treatment,12 gNm^(−2) yr^(−1)).Results showed that N additions generally increased the contents of total nitrogen(TN),ammonia nitrogen(NH_(4)^(+)-N)and nitrate nitrogen(NO_(3)^(−)-N)in different soil layers and the increasing trend was particularly evident in topsoil.Compared with the NN treatment,the average contents of TN in topsoil in the LN,MN and HN treatments during the growing season increased by 10.85%,30.14%and 43.98%,the mean contents of NH_(4)^(+)-N increased by 8.56%,6.96%and 14.34%,and the average contents of NO_(3)^(−)-N increased by 35.73%,45.99%and 46.66%,respectively.Although exogenous N import did not alter the temporal variation patterns of TN contents in organs,the N transfer and accumulation differed among tissues in different treatments.With increasing N import,both the N stocks in soil and plant showed increasing trend and the values in N addition treatments increased by 9.43%–38.22%and 13.40%–62.20%,respectively.It was worth noting that,compared with other treatments,the S.salsa in the MN treatments was very likely to have special response to N enrichment since not only the period of peak growth was prolonged by about 20 days but also the maximum of TN content in leaves was advanced by approximately one month.This paper found that,as N loading reached MN level in future,the growth rhythm of S.salsa and the accumulation and transference of N in its tissues would be altered significantly,which might generate great impact on the stability and health of S.salsa marsh ecosystem.展开更多
[Objective] Under salt stress condition,effects of inoculation of arbuscular mycorrhizal fungi Glomus mosseae on SOD and CAT activity in Suaeda salsa seedlings under salt stress were studied.[Method]There were 2 NaCl ...[Objective] Under salt stress condition,effects of inoculation of arbuscular mycorrhizal fungi Glomus mosseae on SOD and CAT activity in Suaeda salsa seedlings under salt stress were studied.[Method]There were 2 NaCl levels,namely 0 and 400 mmol/L and each NaCl contained 2 treatments,one is inoculated by Glomus mosseae and the other is control.The growths of Suaeda salsa,SOD and CAT activities as well as MDA content in leaves was determined.[Result]Under salt stress condition,Glomus mosseae could increase the growths of Suaeda salsa,SOD and CAT activities in leaves and decreased MDA content in leaves.[Conclusion]It preliminarily demonstrated that Arbuscular Mycorrhizal(AM)Fungi could increase salt resistance of Suaeda salsa by increasing the activities of SOD and CAT as well as alleviating membrane injury.展开更多
AdoMet plays numerous roles of being the major methyl-group donor in trans-methylation reactions. To gain insight into the possible functions of the AdoMet protein of Suaeda salsa L. in response to salt stress, S aden...AdoMet plays numerous roles of being the major methyl-group donor in trans-methylation reactions. To gain insight into the possible functions of the AdoMet protein of Suaeda salsa L. in response to salt stress, S adenosylmethionine synthetase gene (SAMS2) was analyzed. We isolated SAMS2 cDNA clone (AF321001) from a lambda -Zap cDNA library constructed from the halophyte S. salsa Pall aerial tissue treated with 400 mmol/L NaCl. SsSAMS2 was found to encode a S-adenolyl-L-methionine synthetase enzyme (AdoMet synthetase). The fragment was 1 531 bp with an open reading frame of 395 amino acids, the calculated molecular weight was about 43 kD. SsSAMS2 showed the highest homology to SAMS2 gene of Catharanthus roseus G. Don., with 93% identity in deduced amino acid sequence. Southern blotting analysis showed that SsSAMS2 might be a two-copy gene in S. salsa genome. Northern blot indicated that the cDNA was up-regulated by salt and other stresses. Enzyme activity assay indicated that the activity of SAMS2 increased under NaCl stress.展开更多
Two different cDNA clones (Sscat1 and Sscat2) encoding catalase, the primary important H2O2-scavenging enzyme, were isolated from a AZap-cDNA library constructed from a 400 mmol/L NaCl-treated library of Suaeda salsa ...Two different cDNA clones (Sscat1 and Sscat2) encoding catalase, the primary important H2O2-scavenging enzyme, were isolated from a AZap-cDNA library constructed from a 400 mmol/L NaCl-treated library of Suaeda salsa ( L.) Pall aerial tissue. Sscat1 (1.7 kb) contains a full open reading frame of 492 amino acids and Sscat2 (1.1 kb) is a partial clone. BLAST analysis indicates that the two clones share 71.9% identity in nucleotide sequence and 75% identity in deduced amino acid sequence within the last 287 amino acid residues of Sscat1. Southern blotting analysis showed that Sscat1 is multicopy in S. salsa genome, while Sscat2 is a single copy gene. Northern blotting analysis showed a rapid increase in the steady-level of both genes in roots after 48 It salt treatment, but only Sscat1 was induced in salinity treated leaves. Time-course analysis carried out in leaves confirmed that Sscat1 was induced by salt stress, in contrast to Sscat2. These implied that the expression of Sscat1 and Sscat2 genes are differentially regulated in S. salsa. The activity of total catalase is dramatically increased in response to salt stress.展开更多
Suaeda salsa L. seedlings grown in Hoagland nutrient solution were treated with different concentrations of NaCl combined with two levels of K + (12 μmol/L and 6 mmol/L) to study the K + nutrition effect on plant g...Suaeda salsa L. seedlings grown in Hoagland nutrient solution were treated with different concentrations of NaCl combined with two levels of K + (12 μmol/L and 6 mmol/L) to study the K + nutrition effect on plant growth and leaf tonoplast V-H +-ATPase and V-H +-PPase activity. Increase of K + supply in the culture solution markedly increased the fresh weight, dry weight and K + content of S. salsa plants. Western blot analysis showed that the leaf V-H +-ATPase of S. salsa was at least composed of A,B,C,D,E and c subunits, and their expression decreased with the increase of NaCl concentration under K + starvation (12 μmol/L K +), but increased under normal K + application (6 mmol/L K +). Leaf V-H +-PPase molecular weight was about 72.6 kD and its expression increased as NaCl concentration increased under both high or low levels of K + concentration in nutrient solution. There was a positive correlation between of V-H +-ATPase or V-H +-PPase activity and the amounts of their expression. Results in this study suggest that K + nutrition plays an important role in the salt tolerance of S. salsa, and K + is involved in the regulation of V-H +-ATPase or V-H +-PPase activity under salt stress.展开更多
[Objective] This study was to investigate the Suaeda salsa community characteristics,further getting the soil chemical properties.[Method] The paired-data of field spectra and corresponding soil physical-chemical prop...[Objective] This study was to investigate the Suaeda salsa community characteristics,further getting the soil chemical properties.[Method] The paired-data of field spectra and corresponding soil physical-chemical property of seventeen samples was used to reveal the relationship between soil chemical property and field spectra（visible and near infra-red spectra）of S.salsa.[Result] The second derivative spectrum of S.salsa at 1 121 nm could reflect the changes of soil organic matter and soil total nitrogen,and that at 1 208 nm could commendably indicate changes of soil total phosphorus and at 724 nm could indicate changes of soil pH.The first derivative spectrum of S.salsa at 353 nm can indicate changes of soil available potassium,and that at 950 nm could commendably reflect the changes of soil salt content.[Conclusion] Our results laid basis for monitoring chemical property of soil covered with S.salsa using remote sensing technology.展开更多
Extremely saline soils are very harsh environments for the growth and survival of most plant species, however, halophytes can grow well. The underlying mechanism of halophyte to resist high saline is not well understo...Extremely saline soils are very harsh environments for the growth and survival of most plant species, however, halophytes can grow well. The underlying mechanism of halophyte to resist high saline is not well understood by us. This study was conducted at the potash mine near the Lop Nur, China, where the effects of the halophyte Suaeda salsa L. on the saline-alkaline soils and its growth and sustainability were investigated. Four plots（in which the salt encrustation layers were removed）, with different soil treatments were evaluated：（1） undisturbed soil, with no additional treatment（T1）;（2） the slag soil zone, in which a 40-cm layer of slag was placed on the undisturbed soil surface（T2）;（3） slag＋sandy soil, in which a 20-cm layer of slag was placed in the lower layer and 20 cm of sandy soil, taken from an area about 70 km away from Lop Nur potash mine, where Tamarix species were growing, was placed in the upper layer（T3）; and（4） a 40-cm sandy soil layer taken from the area where Tamarix species were growing was placed on undisturbed soil（T4）. Soil nutrient contents increased in the four treatments, but salt content only decreased in the T1 treatment. Salt content in the T4 treatment increased over the two-year period, which may be partly attributed to salt deposition from wind-blown dust within the mine and salt accumulation within the surface soil（0–20 cm） in response to high evaporative demands. The S. salsa plants exhibited greater improvements in growth under the T4 treatment than under the T1, T2, and T3 treatments, which demonstrated that low levels of salinity are beneficial for the growth of this species. The T1 treatment was sustainable because of its low cost and superior soil improvement characteristics. Therefore, S. salsa plants not only reduced soil salinity and increased soil nutrient levels, but also ameliorated the plant growth environment, which would be beneficial for both the ecological restoration of the Lop Nur area and similar areas throughout the world.展开更多
Land use practice significantly affects soil properties. Soil is a major sink for atmospheric carbon, and soil organic carbon （SOC） is considered as an essential indicator of soil quality. The objective of this stud...Land use practice significantly affects soil properties. Soil is a major sink for atmospheric carbon, and soil organic carbon （SOC） is considered as an essential indicator of soil quality. The objective of this study was to assess the effects of N and P applied to Suaeda salsa on biomass production, SOC concentration, labile organic carbon （LOC） concentration, SOC pool and carbon management index （CMI） as well as the effect of the land use practice on soil quality of coastal tidal lands in east coastal region of China. The study provided relevant references for coastal exploitation, tidal land management and related study in other countries and regions. The field experiment was laid out in a randomized complete block design, consisting of four N-fertilization rates （0 （NO）, 60 （N1）, 120 （N2） and 180 kg ha-1 （N3））, three P-fertilization rates （0 （P0）, 70 （P1） and 105 kg ha-~ （P2）） and bare land without vegetation. N and P applied to S. salsa on coastal tidal lands significantly affected biomass production （above-ground biomass and roots）, bulk density （Pb）, available N and P, SOC, LOC, SOC pool and CMI. Using statistical analysis, significantly interactions in N and P were observed for biomass production and the dominant factor for S. salsa production was N in continuous 2-yr experiments. There were no significant interactions between N and P for SOC concentration, LOC concentration and SOC pool. However, significant interaction was obtained for CMI at the 0-20 cm depth and N played a dominant role in the variation of CMI. There were significant improvements for soil measured attributes and parameters, which suggested that increasing the rates of N and P significantly decreased Pb at the 0-20 cm depth and increased available N and P, SOC, LOC, SOC pool as well as CMI at both the 0-20 and 20-40 cm depth, respectively. By correlation analysis, there were significantly positive correlations between biomass （above- ground biomass and roots） and SOC as well as LOC in 2010 and 2011 across all soil depth, respectively. The treatment with N at 180 kg ha-~ and P at 105 kg ha-1 was superior to the other treatments. The results from the 2-yr continuous experiments indicated that, in short-term, there were a few accumulation of SOC and LOC concentrations by means of N and P application to S. salsa, whereas in the long run, S. salsa with N and P application was recommended for coastal tidal lands because of its great potential of carbon sequestration, improvements of soil nutrition status and promotion of soil quality.展开更多
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. Therefor...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.展开更多
Little information is available on biogenic elements(carbon, nitrogen, phosphorus and sulfur) and the ecological stoichiometric characteristics of plants in coastal wetlands. To investigate the contents of carbon, nit...Little information is available on biogenic elements(carbon, nitrogen, phosphorus and sulfur) and the ecological stoichiometric characteristics of plants in coastal wetlands. To investigate the contents of carbon, nitrogen, phosphorus and sulfur of plants, and their ecological stoichiometric characteristics in the Yellow(Huanghe) River Delta, plant samples were collected from two typical salt marshes(Suaeda salsa and Phragmites australis wetlands) during the period of from August to October in 2007, and the ratios of C/N, C/P, N/P, C/N/P and C/N/P/S were calculated. Results showed that during the studying period, plant C, N and P were lower than the global average values, and plant N and P were lower than the China's average values. Leaf C and S in Suaeda salsa were significantly lower than those in Phragmites australis(P < 0.05), and leaf N and P in Suaeda salsa and Phragmites australis showed no significant differences(P > 0.05). Average C/N ratios were 23.75 in leaf, 73.36 in stem, 65.67 in root of Suaeda salsa, and 33.77 in leaf, 121.68 in stem, 97.13 in root of Phragmites australis. Average C/N ratios of Suaeda salsa and Phragmites australis were all great than 25, indicating the salt marsh in the Yellow River Delta is an N limitation system. Average C/P ratios were 276.78 in leaf, 709.28 in stem and 1031.32 in root of Suaeda salsa, and 536.94 in leaf, 768.13 in stem and 875.22 in root of Phragmites australis. The average N/P ratios of Suaeda salsa were 12.92 in leaf, 10.77 in stem and 10.91 in root, and the average N/P ratios of Phragmites australis were 16.40 in leaf, 7.40 in stem and 6.92 in root, indicating the Suaeda salsa wetlands were N limited and Phragmites australis wetlands were N limited in August and P limited in October in 2007. The average C/N, C/P and C/N/P ratios in Suaeda salsa and Pragmites australis were higher than the global average values, indicating the lower quality of organic matter provided by wetland plants in the Yellow River delta.展开更多
The halophyte Suaeda salsa can grow in heavy metal-polluted areas along intertidal zones having high salinity.Since phytochelatins can effectively chelate heavy metals,it was hypothesized that S.salsa possessed a phyt...The halophyte Suaeda salsa can grow in heavy metal-polluted areas along intertidal zones having high salinity.Since phytochelatins can effectively chelate heavy metals,it was hypothesized that S.salsa possessed a phytochelatin synthase(PCS) gene.In the present study,the cDNA of PCS was obtained from S.salsa(designated as SsPCS) using homologous cloning and the rapid amplification of cDNA ends(RACE).A sequence analysis revealed that SsPCS consisted of 1 916 bp nucleotides,encoding a polypeptide of 492 amino acids with one phytochelatin domain and one phytochelatin C domain.A similarity analysis suggested that SsPCS shared up to a 58.6%identity with other PCS proteins and clustered with PCS proteins from eudicots.There was a new kind of metal ion sensor motif in its C-terminal domain.The SsPCS transcript was more highly expressed in elongated and fibered roots and stems(P<0.05) than in leaves.Lead and mercury exposure significantly enhanced the mRNA expression of SsPCS(P<0.05).To the best of our knowledge,SsPCS is the second PCS gene cloned from a halophyte,and it might contain a different metal sensing capability than the first PCS from Thellungiella halophila.This study provided a new view of halophyte PCS genes in heavy metal tolerance.展开更多
We have done a comparative study of ion status, growth and biochemical parameters in shoots and roots of seablite (Suaeda altissima (L.) Pall.) and spinach (Spinacia oleracea L.) grown with different salinity levels i...We have done a comparative study of ion status, growth and biochemical parameters in shoots and roots of seablite (Suaeda altissima (L.) Pall.) and spinach (Spinacia oleracea L.) grown with different salinity levels in the medium (0.5 - 750 mМ). A distinctive feature of the halophyte was a high Na+ content in tissues at its low concentration in the medium (0.5 mM). In these conditions, Na+ accumulation in seablite roots was four-fold higher than in spinach roots, and Na+ content in seablite leaves was almost 20-fold higher than in spinach. Together with an increase in sodium concentration in the medium, K+ content decreased six-fold in seablite leaves, while in spinach it did not decrease so drastically. We can suppose that in the halophyte, some processes occur only in the presence of sodium, and these functions of sodium cannot be fully fulfilled by potassium. Analysis of protein and total nitrogen content in tissues shows that at high salinity, the ability to synthesize non-protein nitrogen-containing compounds increases in the halophyte and decreases in the glycophyte. Data on proline content dynamics show that its increase in tissues of spinach (salinity levels 150 and 250 mМ) and seablite (salinity levels 0.5 and 750 mМ) is an indicator of plant injury. In seablite and spinach, proline is not a major osmoregulator. Its concentration both in roots and leaves was no more than 2.5 μmol/g fresh weight. The data presented in this work concern the accumulation and distribution of Na+, Cl?, K+ and ions, as well as growth and biochemical parameters. Our data show that the development of adaptation reactions in the whole plants in the conditions of high salinity is determined by morphofunctional systems and their interaction.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.41371104,41971128)the Award Program for Min River Scholar in Fujian Province(No.Min[2015]31).
文摘To determine the potential impacts of exogenous nitrogen(N)enrichment on distribution and transfer of N in Suaeda salsa marsh in the Yellow River Estuary,the variations of N in plant-soil system during the growing season were investigated by field N addition experiment.The experiment included four treatments:NN(no N input treatment,0gNm^(−2) yr^(−1)),LN(low N input treatment,3.0 gNm^(−2) yr^(−1)),MN(medium N input treatment,6 gNm^(−2) yr^(−1))and HN(high N input treatment,12 gNm^(−2) yr^(−1)).Results showed that N additions generally increased the contents of total nitrogen(TN),ammonia nitrogen(NH_(4)^(+)-N)and nitrate nitrogen(NO_(3)^(−)-N)in different soil layers and the increasing trend was particularly evident in topsoil.Compared with the NN treatment,the average contents of TN in topsoil in the LN,MN and HN treatments during the growing season increased by 10.85%,30.14%and 43.98%,the mean contents of NH_(4)^(+)-N increased by 8.56%,6.96%and 14.34%,and the average contents of NO_(3)^(−)-N increased by 35.73%,45.99%and 46.66%,respectively.Although exogenous N import did not alter the temporal variation patterns of TN contents in organs,the N transfer and accumulation differed among tissues in different treatments.With increasing N import,both the N stocks in soil and plant showed increasing trend and the values in N addition treatments increased by 9.43%–38.22%and 13.40%–62.20%,respectively.It was worth noting that,compared with other treatments,the S.salsa in the MN treatments was very likely to have special response to N enrichment since not only the period of peak growth was prolonged by about 20 days but also the maximum of TN content in leaves was advanced by approximately one month.This paper found that,as N loading reached MN level in future,the growth rhythm of S.salsa and the accumulation and transference of N in its tissues would be altered significantly,which might generate great impact on the stability and health of S.salsa marsh ecosystem.
基金Supported by the National Natural Science Foundation of China(30670177)State Ocean863Project(2007AA091701)~~
文摘[Objective] Under salt stress condition,effects of inoculation of arbuscular mycorrhizal fungi Glomus mosseae on SOD and CAT activity in Suaeda salsa seedlings under salt stress were studied.[Method]There were 2 NaCl levels,namely 0 and 400 mmol/L and each NaCl contained 2 treatments,one is inoculated by Glomus mosseae and the other is control.The growths of Suaeda salsa,SOD and CAT activities as well as MDA content in leaves was determined.[Result]Under salt stress condition,Glomus mosseae could increase the growths of Suaeda salsa,SOD and CAT activities in leaves and decreased MDA content in leaves.[Conclusion]It preliminarily demonstrated that Arbuscular Mycorrhizal(AM)Fungi could increase salt resistance of Suaeda salsa by increasing the activities of SOD and CAT as well as alleviating membrane injury.
文摘AdoMet plays numerous roles of being the major methyl-group donor in trans-methylation reactions. To gain insight into the possible functions of the AdoMet protein of Suaeda salsa L. in response to salt stress, S adenosylmethionine synthetase gene (SAMS2) was analyzed. We isolated SAMS2 cDNA clone (AF321001) from a lambda -Zap cDNA library constructed from the halophyte S. salsa Pall aerial tissue treated with 400 mmol/L NaCl. SsSAMS2 was found to encode a S-adenolyl-L-methionine synthetase enzyme (AdoMet synthetase). The fragment was 1 531 bp with an open reading frame of 395 amino acids, the calculated molecular weight was about 43 kD. SsSAMS2 showed the highest homology to SAMS2 gene of Catharanthus roseus G. Don., with 93% identity in deduced amino acid sequence. Southern blotting analysis showed that SsSAMS2 might be a two-copy gene in S. salsa genome. Northern blot indicated that the cDNA was up-regulated by salt and other stresses. Enzyme activity assay indicated that the activity of SAMS2 increased under NaCl stress.
文摘Two different cDNA clones (Sscat1 and Sscat2) encoding catalase, the primary important H2O2-scavenging enzyme, were isolated from a AZap-cDNA library constructed from a 400 mmol/L NaCl-treated library of Suaeda salsa ( L.) Pall aerial tissue. Sscat1 (1.7 kb) contains a full open reading frame of 492 amino acids and Sscat2 (1.1 kb) is a partial clone. BLAST analysis indicates that the two clones share 71.9% identity in nucleotide sequence and 75% identity in deduced amino acid sequence within the last 287 amino acid residues of Sscat1. Southern blotting analysis showed that Sscat1 is multicopy in S. salsa genome, while Sscat2 is a single copy gene. Northern blotting analysis showed a rapid increase in the steady-level of both genes in roots after 48 It salt treatment, but only Sscat1 was induced in salinity treated leaves. Time-course analysis carried out in leaves confirmed that Sscat1 was induced by salt stress, in contrast to Sscat2. These implied that the expression of Sscat1 and Sscat2 genes are differentially regulated in S. salsa. The activity of total catalase is dramatically increased in response to salt stress.
文摘Suaeda salsa L. seedlings grown in Hoagland nutrient solution were treated with different concentrations of NaCl combined with two levels of K + (12 μmol/L and 6 mmol/L) to study the K + nutrition effect on plant growth and leaf tonoplast V-H +-ATPase and V-H +-PPase activity. Increase of K + supply in the culture solution markedly increased the fresh weight, dry weight and K + content of S. salsa plants. Western blot analysis showed that the leaf V-H +-ATPase of S. salsa was at least composed of A,B,C,D,E and c subunits, and their expression decreased with the increase of NaCl concentration under K + starvation (12 μmol/L K +), but increased under normal K + application (6 mmol/L K +). Leaf V-H +-PPase molecular weight was about 72.6 kD and its expression increased as NaCl concentration increased under both high or low levels of K + concentration in nutrient solution. There was a positive correlation between of V-H +-ATPase or V-H +-PPase activity and the amounts of their expression. Results in this study suggest that K + nutrition plays an important role in the salt tolerance of S. salsa, and K + is involved in the regulation of V-H +-ATPase or V-H +-PPase activity under salt stress.
基金Supported by National Natural Science Foundation of China(40771172)Program for the Independent Innovation Team at State Key Laboratory of Resources and Environmental Information System(088RA400SA)Pilot Program of Knowledge Innovation Projectfrom Chinese Academy of Science~~
文摘[Objective] This study was to investigate the Suaeda salsa community characteristics,further getting the soil chemical properties.[Method] The paired-data of field spectra and corresponding soil physical-chemical property of seventeen samples was used to reveal the relationship between soil chemical property and field spectra（visible and near infra-red spectra）of S.salsa.[Result] The second derivative spectrum of S.salsa at 1 121 nm could reflect the changes of soil organic matter and soil total nitrogen,and that at 1 208 nm could commendably indicate changes of soil total phosphorus and at 724 nm could indicate changes of soil pH.The first derivative spectrum of S.salsa at 353 nm can indicate changes of soil available potassium,and that at 950 nm could commendably reflect the changes of soil salt content.[Conclusion] Our results laid basis for monitoring chemical property of soil covered with S.salsa using remote sensing technology.
基金supported by the Youth Innovation Promotion Association of Chinese Academy of Sciences (2017476)the National High-level Personnel Special Support Program+3 种基金Xinjiang Youth Science and Technology Innovation Leader Project (QN2016BS0162)the National Key Research and Development Program (2017YFSF03024105)the National Natural Science Foundation of China (31700423,31300449)the Xinjiang Uygur Autonomous Region Science and Technology Support Project (201433101)
文摘Extremely saline soils are very harsh environments for the growth and survival of most plant species, however, halophytes can grow well. The underlying mechanism of halophyte to resist high saline is not well understood by us. This study was conducted at the potash mine near the Lop Nur, China, where the effects of the halophyte Suaeda salsa L. on the saline-alkaline soils and its growth and sustainability were investigated. Four plots（in which the salt encrustation layers were removed）, with different soil treatments were evaluated：（1） undisturbed soil, with no additional treatment（T1）;（2） the slag soil zone, in which a 40-cm layer of slag was placed on the undisturbed soil surface（T2）;（3） slag＋sandy soil, in which a 20-cm layer of slag was placed in the lower layer and 20 cm of sandy soil, taken from an area about 70 km away from Lop Nur potash mine, where Tamarix species were growing, was placed in the upper layer（T3）; and（4） a 40-cm sandy soil layer taken from the area where Tamarix species were growing was placed on undisturbed soil（T4）. Soil nutrient contents increased in the four treatments, but salt content only decreased in the T1 treatment. Salt content in the T4 treatment increased over the two-year period, which may be partly attributed to salt deposition from wind-blown dust within the mine and salt accumulation within the surface soil（0–20 cm） in response to high evaporative demands. The S. salsa plants exhibited greater improvements in growth under the T4 treatment than under the T1, T2, and T3 treatments, which demonstrated that low levels of salinity are beneficial for the growth of this species. The T1 treatment was sustainable because of its low cost and superior soil improvement characteristics. Therefore, S. salsa plants not only reduced soil salinity and increased soil nutrient levels, but also ameliorated the plant growth environment, which would be beneficial for both the ecological restoration of the Lop Nur area and similar areas throughout the world.
基金support of the Special Fund for Public-Welfare Industrial (Agriculture) Research of China (200903001)the National Natural Science Foundation of China (41171181,41101199)+1 种基金the Key Technology R&D Program of Jiangsu Province, China (BE2010313)the Prospective Project of Production Education Research Cooperation of Jiangsu Province, China (BY2010013)
文摘Land use practice significantly affects soil properties. Soil is a major sink for atmospheric carbon, and soil organic carbon （SOC） is considered as an essential indicator of soil quality. The objective of this study was to assess the effects of N and P applied to Suaeda salsa on biomass production, SOC concentration, labile organic carbon （LOC） concentration, SOC pool and carbon management index （CMI） as well as the effect of the land use practice on soil quality of coastal tidal lands in east coastal region of China. The study provided relevant references for coastal exploitation, tidal land management and related study in other countries and regions. The field experiment was laid out in a randomized complete block design, consisting of four N-fertilization rates （0 （NO）, 60 （N1）, 120 （N2） and 180 kg ha-1 （N3））, three P-fertilization rates （0 （P0）, 70 （P1） and 105 kg ha-~ （P2）） and bare land without vegetation. N and P applied to S. salsa on coastal tidal lands significantly affected biomass production （above-ground biomass and roots）, bulk density （Pb）, available N and P, SOC, LOC, SOC pool and CMI. Using statistical analysis, significantly interactions in N and P were observed for biomass production and the dominant factor for S. salsa production was N in continuous 2-yr experiments. There were no significant interactions between N and P for SOC concentration, LOC concentration and SOC pool. However, significant interaction was obtained for CMI at the 0-20 cm depth and N played a dominant role in the variation of CMI. There were significant improvements for soil measured attributes and parameters, which suggested that increasing the rates of N and P significantly decreased Pb at the 0-20 cm depth and increased available N and P, SOC, LOC, SOC pool as well as CMI at both the 0-20 and 20-40 cm depth, respectively. By correlation analysis, there were significantly positive correlations between biomass （above- ground biomass and roots） and SOC as well as LOC in 2010 and 2011 across all soil depth, respectively. The treatment with N at 180 kg ha-~ and P at 105 kg ha-1 was superior to the other treatments. The results from the 2-yr continuous experiments indicated that, in short-term, there were a few accumulation of SOC and LOC concentrations by means of N and P application to S. salsa, whereas in the long run, S. salsa with N and P application was recommended for coastal tidal lands because of its great potential of carbon sequestration, improvements of soil nutrition status and promotion of soil quality.
基金Supported by National Natural Science Foundation of China(41771199)Basic Research Project of Jiangsu Province,China(BK20171277)
文摘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.
基金Under the auspices of National Key R&D Program of China(No.2017YFC0505906)National Natural Science Foundation of China(No.51639001,51379012)Interdiscipline Research Funds of Beijing Normal University
文摘Little information is available on biogenic elements(carbon, nitrogen, phosphorus and sulfur) and the ecological stoichiometric characteristics of plants in coastal wetlands. To investigate the contents of carbon, nitrogen, phosphorus and sulfur of plants, and their ecological stoichiometric characteristics in the Yellow(Huanghe) River Delta, plant samples were collected from two typical salt marshes(Suaeda salsa and Phragmites australis wetlands) during the period of from August to October in 2007, and the ratios of C/N, C/P, N/P, C/N/P and C/N/P/S were calculated. Results showed that during the studying period, plant C, N and P were lower than the global average values, and plant N and P were lower than the China's average values. Leaf C and S in Suaeda salsa were significantly lower than those in Phragmites australis(P < 0.05), and leaf N and P in Suaeda salsa and Phragmites australis showed no significant differences(P > 0.05). Average C/N ratios were 23.75 in leaf, 73.36 in stem, 65.67 in root of Suaeda salsa, and 33.77 in leaf, 121.68 in stem, 97.13 in root of Phragmites australis. Average C/N ratios of Suaeda salsa and Phragmites australis were all great than 25, indicating the salt marsh in the Yellow River Delta is an N limitation system. Average C/P ratios were 276.78 in leaf, 709.28 in stem and 1031.32 in root of Suaeda salsa, and 536.94 in leaf, 768.13 in stem and 875.22 in root of Phragmites australis. The average N/P ratios of Suaeda salsa were 12.92 in leaf, 10.77 in stem and 10.91 in root, and the average N/P ratios of Phragmites australis were 16.40 in leaf, 7.40 in stem and 6.92 in root, indicating the Suaeda salsa wetlands were N limited and Phragmites australis wetlands were N limited in August and P limited in October in 2007. The average C/N, C/P and C/N/P ratios in Suaeda salsa and Pragmites australis were higher than the global average values, indicating the lower quality of organic matter provided by wetland plants in the Yellow River delta.
基金Supported by the 100 Talents Program of the Chinese Academy of Sciencesthe Key Technology R&D Program of Shandong Province(No.2012GGA06032)
文摘The halophyte Suaeda salsa can grow in heavy metal-polluted areas along intertidal zones having high salinity.Since phytochelatins can effectively chelate heavy metals,it was hypothesized that S.salsa possessed a phytochelatin synthase(PCS) gene.In the present study,the cDNA of PCS was obtained from S.salsa(designated as SsPCS) using homologous cloning and the rapid amplification of cDNA ends(RACE).A sequence analysis revealed that SsPCS consisted of 1 916 bp nucleotides,encoding a polypeptide of 492 amino acids with one phytochelatin domain and one phytochelatin C domain.A similarity analysis suggested that SsPCS shared up to a 58.6%identity with other PCS proteins and clustered with PCS proteins from eudicots.There was a new kind of metal ion sensor motif in its C-terminal domain.The SsPCS transcript was more highly expressed in elongated and fibered roots and stems(P<0.05) than in leaves.Lead and mercury exposure significantly enhanced the mRNA expression of SsPCS(P<0.05).To the best of our knowledge,SsPCS is the second PCS gene cloned from a halophyte,and it might contain a different metal sensing capability than the first PCS from Thellungiella halophila.This study provided a new view of halophyte PCS genes in heavy metal tolerance.
文摘We have done a comparative study of ion status, growth and biochemical parameters in shoots and roots of seablite (Suaeda altissima (L.) Pall.) and spinach (Spinacia oleracea L.) grown with different salinity levels in the medium (0.5 - 750 mМ). A distinctive feature of the halophyte was a high Na+ content in tissues at its low concentration in the medium (0.5 mM). In these conditions, Na+ accumulation in seablite roots was four-fold higher than in spinach roots, and Na+ content in seablite leaves was almost 20-fold higher than in spinach. Together with an increase in sodium concentration in the medium, K+ content decreased six-fold in seablite leaves, while in spinach it did not decrease so drastically. We can suppose that in the halophyte, some processes occur only in the presence of sodium, and these functions of sodium cannot be fully fulfilled by potassium. Analysis of protein and total nitrogen content in tissues shows that at high salinity, the ability to synthesize non-protein nitrogen-containing compounds increases in the halophyte and decreases in the glycophyte. Data on proline content dynamics show that its increase in tissues of spinach (salinity levels 150 and 250 mМ) and seablite (salinity levels 0.5 and 750 mМ) is an indicator of plant injury. In seablite and spinach, proline is not a major osmoregulator. Its concentration both in roots and leaves was no more than 2.5 μmol/g fresh weight. The data presented in this work concern the accumulation and distribution of Na+, Cl?, K+ and ions, as well as growth and biochemical parameters. Our data show that the development of adaptation reactions in the whole plants in the conditions of high salinity is determined by morphofunctional systems and their interaction.
