[Objective] The aim was to propose a new entropy weight fuzzy compre- hensive evaluation method for assessing cotton salt tolerance, realizing the objective, accurate and comprehensive evaluation of salt tolerance of ...[Objective] The aim was to propose a new entropy weight fuzzy compre- hensive evaluation method for assessing cotton salt tolerance, realizing the objective, accurate and comprehensive evaluation of salt tolerance of cotton. [Method] A sand culture experiment under salt stress of 150 mmol/L of NaCI was designed. The in- dicator weight was determined with the entropy weight fuzzy comprehensive evalu- ation method, based on the salt injury index of indicators. The salt tolerance of cotton was evaluated comprehensively. [Result] At the germination stage, the entropy and weight of salt injury index of germination energy, vigor index, hypocotyl length and fresh weight were highest, followed by germination rate and germination index, and of root length were lowest. At the seedling stage, the entropy and weight of salt injury index of plasma membrane permeability, root vigor and leaf expansion rate were highest, followed by plant height and net photosynthetic rate, and of shoot dry weight and root dry weight were lowest. The salt tolerance of cotton differed a- mong growth stages and cultivars. Among the 11 cultivars, CCRI-44 and CCRI-75 were steadily salt-tolerant at both germination and seedling stages; CCRI-17, Sumi- an 22, Sumian 15 and Dexiamianl had a stable moderate salt tolerance; while Sumian 12 and Simian 3 were steadily salt-sensitive. [Conclusion] The evaluated result was objective and exact, which indicated that this method could be used in comprehensive evaluation of salt tolerance of cotton.展开更多
The selection and application of salt tolerance varieties in peanut is impor- tant for the exploitation of saline soil. In this study, 41 peanut varieties were select- ed for the evaluation of salt tolerance in both g...The selection and application of salt tolerance varieties in peanut is impor- tant for the exploitation of saline soil. In this study, 41 peanut varieties were select- ed for the evaluation of salt tolerance in both germination and young seedling stage. The results showed the germination and growth of peanut were significantly inhibited by salt stress, which were enhanced by salt concentration increasing. The 0.5% NaCI was selected as the most suitable concentration for further identification, and the characters in germination stage (including the relative germination potential, relative germination rate and germination index) and young seedling stage (including relative main root length, seedling height, fresh weight, dry weight, et aL) were measured. Cluster analysis showed the varieties could be divided into different groups, and 9 and 3 salt-tolerant varieties were identified in the two stages, respec- tively, including two varieties performed well in both two stages, which could be useful for the breeding of new salt tolerance varieties and the study of salt toler- ance mechanism.展开更多
For screening out salt tolerance germplasm and providing materials for ge- netic research of peanut, based on the indexes including relative germination poten- tial, relative germination rate, relative germination ind...For screening out salt tolerance germplasm and providing materials for ge- netic research of peanut, based on the indexes including relative germination poten- tial, relative germination rate, relative germination index and salt-injury rate, 128 peanut germplasms were selected for salt-tolerant identification and estimation under 2.5% NaCI. We found significant but various depressing levels of germination rate under salt stress among different germplasms, and only 5% of 128 germplasms were highly resistant to salinity. We also found that the relative germination index was a useful evaluation index for salt tolerance besides salt damage rate and rela- tive germination rate. After all, we comprehensively screened out 7 materials (JS011, JS024, JS125, JS491, JS523, JS524 and JS525) as salt tolerance germplasms for further research. Key展开更多
Experiments on the partitioning of Cu between different granitic silicate melts and the respective coexisting aqueous fluids have been performed under conditions of 850 ℃, 100 MPa and oxygen fugacity (fO2) buffered...Experiments on the partitioning of Cu between different granitic silicate melts and the respective coexisting aqueous fluids have been performed under conditions of 850 ℃, 100 MPa and oxygen fugacity (fO2) buffered at approaching Ni-NiO (NNO). Partition coefficients of Cu (Dcu = Cfluid/Cmelt) were varied with different alumina/alkali mole ratios [Al2O3/(Na2O + K2O), abbreviated as Al/ Alk], Na/K mole ratios, and SiO2 mole contents. The DCu increased from 1.28 ± 0.01 to 22.18 ±0.22 with the increase of Al/Alk mole ratios (ranging from 0.64 to 1.20) and Na/K mole ratios (ranging from 0.58 to 2.56). The experimental results also showed that Dcu was positively correlated with the HCl concentration of the starting fluid. The Dcu was independent of the SiO2 mole content in the range of SiO2 content considered. No Dcu value was less than 1 in our experiments at 850 ℃ and 100 MPa, indicating that Cu preferred to enter the fluid phase rather than the coexisting melt phase under most conditions in the melt-fluid system, and thus a significant amount of Cu could be transported in the fluid phase in the magmatichydrothermal environment. The results indicated that Cu favored partitioning into the aqueous fluid rather than the melt phase if there was a high Na/K ratio, Na-rich, peraluminous granitic melt coexisting with the high Cl^- fluid.展开更多
Tertiary amine cationic polyacrylamide with high cationization degree was used as a new cationic agent to pretreat cotton with dip-pad-bake method. The obtained cationic cotton was dyed with reactive dyes in the ab-se...Tertiary amine cationic polyacrylamide with high cationization degree was used as a new cationic agent to pretreat cotton with dip-pad-bake method. The obtained cationic cotton was dyed with reactive dyes in the ab-sence of electrolyte. The effects of the characteristics of the cationic agent and the pretreatment conditions on dye-ability of reactive dye were investigated. The results showed that the fixation and K/S values of the reactive dyes on the cationic cotton were improved compared with those on the untreated one in the presence of salt. Tests on fast-ness properties of the dyed cotton and fabric quality of the pretreated cotton were carried out and the results showed that wash and rub fastness of the salt-free dyeing were both satisfactory. And anti-crease property,tensile and tear strength,and handling of the cationic cotton were also good compared with that of the untreated one.展开更多
The paper aimed to investigate the growth of seedlings of three species of Cassia (C tora, C. sophera and C occidentalis) at different concentrations of salinity (NaC1) and pH treatments. All the species showed th...The paper aimed to investigate the growth of seedlings of three species of Cassia (C tora, C. sophera and C occidentalis) at different concentrations of salinity (NaC1) and pH treatments. All the species showed the highest seedling length under control condition, and with the increase of salinity, C occidentalis showed the highest sensitivity. The seedling length of C tora at 0.05 M NaCI significantly (P = 0.05) decreased to 5.71 cm, and further increase of salinity to 0.1 M, the seedling length was decreased to less than the value of 0.05 M NaC1 treatment and one-third (2.15 cm) of that of control (6.92 cm). Seeds of all the species failed to germinate at 0.5 M NaC1. Scarified seeds of C. sophera and C occidentalis increased seedling length. The highest seedling length was in C. sophera, followed by C. tora and C. occidentalis. All the species showed significant decrease (P 〈 0.05) of fresh weight with the increase of salinity; scarification of seeds in C. occidentalis and C. sophera showed higher fresh weight than those of without scarification. Experiments at different pH levels did not show any significant (P = 0.05) change in seedling length, except C. sophera, while at acidic pH, both seedling length and dry weight were significantly (P 〈 0.05) decreased.展开更多
This experiment was conducted in Horticulture Department, School of Plant Production, Faculty of Agriculture and Forestry, University of Duhok, Iraq in 2010 on Chrysanthemum plants, in order to mitigate the adverse in...This experiment was conducted in Horticulture Department, School of Plant Production, Faculty of Agriculture and Forestry, University of Duhok, Iraq in 2010 on Chrysanthemum plants, in order to mitigate the adverse influence of salinity by the use of liquorice root extract and study its effect on vegetative growth, chlorophyll content in leaves from chlorophyll and assistant pigment, carbohydrate and starch. Subsequently, the trail consisted of three levels of salinity (0, 4 and 8 ds m^-1) and three concentrations of the liquorice root extract 0, 2.5 and 5 g L^-1. Results showed that salinity (4 ds m^-1) rate caused significant increases in certain vegetative characteristics (branches number, plant height, leaves number and leaf area), photosynthetic pigments (Chl a, Chl b, total chlorophyll, a-carotene, β-carotene, zeaxanthin, astaxanthin), fresh shoot weight, fresh root weight, shoot dry weight, root dry weight, shoot: root ratio, carbohydrate dry weight percentage and starch percentage as compared to untreated check. However, increasing salinity rate to 8 ds m^-1 resulted in substantial reductions in all above mentioned Waits. Treatment with liquorices root extract, in particular, 5 g L^-1 manifested a potent capability in ameliorating the salinity negative effects in terms of vegetative and photosynthetic pigments aspects.展开更多
Nutrimental requirements of heliophytic poinsettias have not yet been determined, this information is essential for developing an adequate technological package to orient producers in its management. The behavior of t...Nutrimental requirements of heliophytic poinsettias have not yet been determined, this information is essential for developing an adequate technological package to orient producers in its management. The behavior of the plant under nutritional stress needs to be known by the application of a hydroponic system. The objective of the present work was to evaluate the physiological effect of induced deficiencies of five macronutriments (nitrogen, phosphorous, potassium, calcium, and magnesium) and its influence on the pigment production of the poinsettia Euphorbia puleherrima cv. "Valenciana". The study was made during 2010 at the Research Unit "Dr. Ramon Fernandez Gonzalez" in Texcoco, State of Mexico. Six treatments were tested during 240 days from transplant in a totally randomized experimental design. Chlorophylls contents were determined at the beginning of the experiment. At the end of the treatment period, the contents of nutrients, chlorophylls, leaf carotenoids and bract anthocyanins were determined. The effects observed as results of the treatments were: reduction in plant height and diameter; the lowest content of total chlorophylls was observed in the absence of nitrogen, the largest reduction being of chlorophyll a and carotenoids; a low content of anthocyanins was observed to be associated with low nitrogen and calcium; a high correlation was found between nitrogen supplementation and measured non-destructively with a SPAD 502 Minolta unit values measured intensity of green color of leaves.展开更多
Spartina alterniflora is ecologically important in its original habitat; however, it has caused controversy since it was introduction into China(now it has been spreading rapidly on the Jiangsu, Shanghai, Zhejiang and...Spartina alterniflora is ecologically important in its original habitat; however, it has caused controversy since it was introduction into China(now it has been spreading rapidly on the Jiangsu, Shanghai, Zhejiang and Fujian coasts). The purpose of the present contribution is, on the basis of an analysis and synthesis of existing data sets, to evaluate the environmental-ecological effects of S. alterniflora, and to identify the relevant scientific problems that require further research in the future. Investigations have shown that, by reducing the near-bed shear stress associated with tidal currents, S. alterniflora can enhance the settling flux of suspended sediment and deposition rate on the tidal flats over the region. Further, field survey and analysis indicate that the S. alterniflora salt-marsh has a high primary production and provides a new type of habitat for the native benthic fauna. Some macro-, meio- and micro-fauna that used to live in the native salt-marshes have adapted to the S. alterniflora salt-marsh, forming a new ecosystem. Under the influences of a number of background factors, such as latitude variations and the coastal type, the environmental-ecological changes induced by Spartine have regional differentiations. To the north of Hangzhou Bay, with a high position of the pre-Holocene stratum base, a large width of the tidal flats, and a gentle bed slope, only a small part of the intertidal zone is occupied by the S. alterniflora salt-marsh. Here, the S. alterniflora salt-marshes mainly play a positive role in coastal protection and ecosystem functioning. In contrary, to the South of Hangzhou Bay, The pre-Holocene deposits are situated in relatively deeo waters, and the width of the tidal flats formed within coastal embayments is relatively narrow. As such, the expansion of S. alterniflora has squeezed the living space of other intertidal organisms, thus has a negative ecological effect. Therefore, the regional differentiation of the Spartina effects should be sufficiently considered in coastal development and management. Furthermore, in order to predict the future evolution of the S. alterniflora wetlands over the region, in addition to in situ monitoring and measurements, an ecosystem dynamic model should be established, taking into account the coupling of the rerrestrial and marine environmental-ecological processes.展开更多
A sand culture experiment was conducted to determine the effects of different seawater (5% and 10%) treatments on plant growth,inorganic ions,indole alkaloid concentrations and yields of Catharanthus roseus,in an effo...A sand culture experiment was conducted to determine the effects of different seawater (5% and 10%) treatments on plant growth,inorganic ions,indole alkaloid concentrations and yields of Catharanthus roseus,in an effort to increase the alkaloid yield by artificial cultivation.The total fresh and dry weights and tissue K + concentrations decreased,but Na + concentrations increased in the plant roots,stems and leaves of C.roseus under seawater stress as compared to the control.The concentrations and yields of vindoline,catharanthine,vinblastine and vincristine increased under seawater stress.The concentrations and yields of these alkaloids were higher in 5% seawater-treated plants than those in the 10% seawater-treated plants.Considering the industrial production,5% seawater treatments could reduce the cost of producing alkaloid.In the control plants,the highest alkaloid concentrations reached a peak at 100 days after planting,suggesting that plant harvest must be optimized in terms of growth duration.展开更多
Research for changes of soil water and salt is an important content of land sciences and agriculture sciences in arid and semi arid regions. In this paper, sampling in actual agricultural fields, laboratory analysis o...Research for changes of soil water and salt is an important content of land sciences and agriculture sciences in arid and semi arid regions. In this paper, sampling in actual agricultural fields, laboratory analysis of soil samples and statistical analysis methods are used to quantitatively analyze soil salinity changes under different ir- rigation methods throughout the cotton growing season in Shihezi reclamation area. The results show that irrigation methods play an important role in soil salt content in the surface soil (0-20 cm) and sub-deep soil (40-60 cm), fol- lowed by deep soil layer (60-100 cm) and root soil layer (20-40 cm). Furrow irrigation yields the maximum soil salt content in deep layer (60-100 cm) or sub-deep layer (40-60 cm) and the maximum salinity occurs in the first half of the cotton growing season (June or earlier). In contrast, drip irrigation yields the maximum soil salinity in the root layer (20-40 cm) or sub-deep (40-60 cm), and this usually appears in the second half growing season (July or af- ter). The ratio of chloride ion to sulfate ion (Cl-/SO2- 4) and its change in the soil are on the rise under furrow irrigation while the value first increased and then decreased with a peak point in June under drip irrigation. This suggests that furrow irrigation may shift the type of soil salinization to chloride ion type moreso than drip irrigation. Potassium and sodium ion contents of the soil show that soil sodium+potassium content will drop after the first rise under furrow irrigation and the value is manifested by fluctuations under drip irrigation. Potassium+sodium content change is relatively more stable in the whole cotton growth period under irrigation methods. The maximum of sodium and potassium content of the soil usually occur in deep soil layer (60-100 cm) or sub-deep soil layer (40-60 cm) in most sample points under furrow irrigation while it is inconsistent in different sample points under drip irrigation. A non- parametric test for paired samples is used to analyze differences of soil salt content under different irrigation methods. This analysis shows that the impact of irrigation on soil salinity is most significant in July, followed by August, June, May, and April in most sample points. The most significant impact of irrigation methods occurs in the surface soil layer (0-20 cm), followed by deep layer (60-100 cm), root layer (20-40 cm) and sub-deep (40-60 cm). These conclusions will be benefitial for mitigation of soil salinization, irrigation and fertilization and sustainable land use.展开更多
基金Supported by Jiangsu Agricultural Science and Technology Innovation Fund(CX(12)5035)Jiangsu Agricultural "Three New Engineering" Project(SXGC[2014]299)~~
文摘[Objective] The aim was to propose a new entropy weight fuzzy compre- hensive evaluation method for assessing cotton salt tolerance, realizing the objective, accurate and comprehensive evaluation of salt tolerance of cotton. [Method] A sand culture experiment under salt stress of 150 mmol/L of NaCI was designed. The in- dicator weight was determined with the entropy weight fuzzy comprehensive evalu- ation method, based on the salt injury index of indicators. The salt tolerance of cotton was evaluated comprehensively. [Result] At the germination stage, the entropy and weight of salt injury index of germination energy, vigor index, hypocotyl length and fresh weight were highest, followed by germination rate and germination index, and of root length were lowest. At the seedling stage, the entropy and weight of salt injury index of plasma membrane permeability, root vigor and leaf expansion rate were highest, followed by plant height and net photosynthetic rate, and of shoot dry weight and root dry weight were lowest. The salt tolerance of cotton differed a- mong growth stages and cultivars. Among the 11 cultivars, CCRI-44 and CCRI-75 were steadily salt-tolerant at both germination and seedling stages; CCRI-17, Sumi- an 22, Sumian 15 and Dexiamianl had a stable moderate salt tolerance; while Sumian 12 and Simian 3 were steadily salt-sensitive. [Conclusion] The evaluated result was objective and exact, which indicated that this method could be used in comprehensive evaluation of salt tolerance of cotton.
文摘The selection and application of salt tolerance varieties in peanut is impor- tant for the exploitation of saline soil. In this study, 41 peanut varieties were select- ed for the evaluation of salt tolerance in both germination and young seedling stage. The results showed the germination and growth of peanut were significantly inhibited by salt stress, which were enhanced by salt concentration increasing. The 0.5% NaCI was selected as the most suitable concentration for further identification, and the characters in germination stage (including the relative germination potential, relative germination rate and germination index) and young seedling stage (including relative main root length, seedling height, fresh weight, dry weight, et aL) were measured. Cluster analysis showed the varieties could be divided into different groups, and 9 and 3 salt-tolerant varieties were identified in the two stages, respec- tively, including two varieties performed well in both two stages, which could be useful for the breeding of new salt tolerance varieties and the study of salt toler- ance mechanism.
基金Supported by National Peanut Industry Technology System"Nanjing Comprehensive Experimental Station"(CARS-14)the Fund of Independent Innovation of Agricultural Science and Technology in Jiangsu Province"On the Collection,Identification and Shared Service of Germplasm Resources of Main Field Crops"[CX(14)2001]~~
文摘For screening out salt tolerance germplasm and providing materials for ge- netic research of peanut, based on the indexes including relative germination poten- tial, relative germination rate, relative germination index and salt-injury rate, 128 peanut germplasms were selected for salt-tolerant identification and estimation under 2.5% NaCI. We found significant but various depressing levels of germination rate under salt stress among different germplasms, and only 5% of 128 germplasms were highly resistant to salinity. We also found that the relative germination index was a useful evaluation index for salt tolerance besides salt damage rate and rela- tive germination rate. After all, we comprehensively screened out 7 materials (JS011, JS024, JS125, JS491, JS523, JS524 and JS525) as salt tolerance germplasms for further research. Key
文摘Experiments on the partitioning of Cu between different granitic silicate melts and the respective coexisting aqueous fluids have been performed under conditions of 850 ℃, 100 MPa and oxygen fugacity (fO2) buffered at approaching Ni-NiO (NNO). Partition coefficients of Cu (Dcu = Cfluid/Cmelt) were varied with different alumina/alkali mole ratios [Al2O3/(Na2O + K2O), abbreviated as Al/ Alk], Na/K mole ratios, and SiO2 mole contents. The DCu increased from 1.28 ± 0.01 to 22.18 ±0.22 with the increase of Al/Alk mole ratios (ranging from 0.64 to 1.20) and Na/K mole ratios (ranging from 0.58 to 2.56). The experimental results also showed that Dcu was positively correlated with the HCl concentration of the starting fluid. The Dcu was independent of the SiO2 mole content in the range of SiO2 content considered. No Dcu value was less than 1 in our experiments at 850 ℃ and 100 MPa, indicating that Cu preferred to enter the fluid phase rather than the coexisting melt phase under most conditions in the melt-fluid system, and thus a significant amount of Cu could be transported in the fluid phase in the magmatichydrothermal environment. The results indicated that Cu favored partitioning into the aqueous fluid rather than the melt phase if there was a high Na/K ratio, Na-rich, peraluminous granitic melt coexisting with the high Cl^- fluid.
基金Supported by the National Science Foundation for Distinguished Young Scholar of China(20525620) the National Natural Science Foundation of China(20806013) the Program for Changjiang Scholar and Innovative Research Team in University(IRT 0711)
文摘Tertiary amine cationic polyacrylamide with high cationization degree was used as a new cationic agent to pretreat cotton with dip-pad-bake method. The obtained cationic cotton was dyed with reactive dyes in the ab-sence of electrolyte. The effects of the characteristics of the cationic agent and the pretreatment conditions on dye-ability of reactive dye were investigated. The results showed that the fixation and K/S values of the reactive dyes on the cationic cotton were improved compared with those on the untreated one in the presence of salt. Tests on fast-ness properties of the dyed cotton and fabric quality of the pretreated cotton were carried out and the results showed that wash and rub fastness of the salt-free dyeing were both satisfactory. And anti-crease property,tensile and tear strength,and handling of the cationic cotton were also good compared with that of the untreated one.
文摘The paper aimed to investigate the growth of seedlings of three species of Cassia (C tora, C. sophera and C occidentalis) at different concentrations of salinity (NaC1) and pH treatments. All the species showed the highest seedling length under control condition, and with the increase of salinity, C occidentalis showed the highest sensitivity. The seedling length of C tora at 0.05 M NaCI significantly (P = 0.05) decreased to 5.71 cm, and further increase of salinity to 0.1 M, the seedling length was decreased to less than the value of 0.05 M NaC1 treatment and one-third (2.15 cm) of that of control (6.92 cm). Seeds of all the species failed to germinate at 0.5 M NaC1. Scarified seeds of C. sophera and C occidentalis increased seedling length. The highest seedling length was in C. sophera, followed by C. tora and C. occidentalis. All the species showed significant decrease (P 〈 0.05) of fresh weight with the increase of salinity; scarification of seeds in C. occidentalis and C. sophera showed higher fresh weight than those of without scarification. Experiments at different pH levels did not show any significant (P = 0.05) change in seedling length, except C. sophera, while at acidic pH, both seedling length and dry weight were significantly (P 〈 0.05) decreased.
文摘This experiment was conducted in Horticulture Department, School of Plant Production, Faculty of Agriculture and Forestry, University of Duhok, Iraq in 2010 on Chrysanthemum plants, in order to mitigate the adverse influence of salinity by the use of liquorice root extract and study its effect on vegetative growth, chlorophyll content in leaves from chlorophyll and assistant pigment, carbohydrate and starch. Subsequently, the trail consisted of three levels of salinity (0, 4 and 8 ds m^-1) and three concentrations of the liquorice root extract 0, 2.5 and 5 g L^-1. Results showed that salinity (4 ds m^-1) rate caused significant increases in certain vegetative characteristics (branches number, plant height, leaves number and leaf area), photosynthetic pigments (Chl a, Chl b, total chlorophyll, a-carotene, β-carotene, zeaxanthin, astaxanthin), fresh shoot weight, fresh root weight, shoot dry weight, root dry weight, shoot: root ratio, carbohydrate dry weight percentage and starch percentage as compared to untreated check. However, increasing salinity rate to 8 ds m^-1 resulted in substantial reductions in all above mentioned Waits. Treatment with liquorices root extract, in particular, 5 g L^-1 manifested a potent capability in ameliorating the salinity negative effects in terms of vegetative and photosynthetic pigments aspects.
文摘Nutrimental requirements of heliophytic poinsettias have not yet been determined, this information is essential for developing an adequate technological package to orient producers in its management. The behavior of the plant under nutritional stress needs to be known by the application of a hydroponic system. The objective of the present work was to evaluate the physiological effect of induced deficiencies of five macronutriments (nitrogen, phosphorous, potassium, calcium, and magnesium) and its influence on the pigment production of the poinsettia Euphorbia puleherrima cv. "Valenciana". The study was made during 2010 at the Research Unit "Dr. Ramon Fernandez Gonzalez" in Texcoco, State of Mexico. Six treatments were tested during 240 days from transplant in a totally randomized experimental design. Chlorophylls contents were determined at the beginning of the experiment. At the end of the treatment period, the contents of nutrients, chlorophylls, leaf carotenoids and bract anthocyanins were determined. The effects observed as results of the treatments were: reduction in plant height and diameter; the lowest content of total chlorophylls was observed in the absence of nitrogen, the largest reduction being of chlorophyll a and carotenoids; a low content of anthocyanins was observed to be associated with low nitrogen and calcium; a high correlation was found between nitrogen supplementation and measured non-destructively with a SPAD 502 Minolta unit values measured intensity of green color of leaves.
基金supported financially by the Basic Research Project in Jiangsu Province (Grant No. SBK2011012)an National Natural Science Foundation of China (Grant No. 40476041)
文摘Spartina alterniflora is ecologically important in its original habitat; however, it has caused controversy since it was introduction into China(now it has been spreading rapidly on the Jiangsu, Shanghai, Zhejiang and Fujian coasts). The purpose of the present contribution is, on the basis of an analysis and synthesis of existing data sets, to evaluate the environmental-ecological effects of S. alterniflora, and to identify the relevant scientific problems that require further research in the future. Investigations have shown that, by reducing the near-bed shear stress associated with tidal currents, S. alterniflora can enhance the settling flux of suspended sediment and deposition rate on the tidal flats over the region. Further, field survey and analysis indicate that the S. alterniflora salt-marsh has a high primary production and provides a new type of habitat for the native benthic fauna. Some macro-, meio- and micro-fauna that used to live in the native salt-marshes have adapted to the S. alterniflora salt-marsh, forming a new ecosystem. Under the influences of a number of background factors, such as latitude variations and the coastal type, the environmental-ecological changes induced by Spartine have regional differentiations. To the north of Hangzhou Bay, with a high position of the pre-Holocene stratum base, a large width of the tidal flats, and a gentle bed slope, only a small part of the intertidal zone is occupied by the S. alterniflora salt-marsh. Here, the S. alterniflora salt-marshes mainly play a positive role in coastal protection and ecosystem functioning. In contrary, to the South of Hangzhou Bay, The pre-Holocene deposits are situated in relatively deeo waters, and the width of the tidal flats formed within coastal embayments is relatively narrow. As such, the expansion of S. alterniflora has squeezed the living space of other intertidal organisms, thus has a negative ecological effect. Therefore, the regional differentiation of the Spartina effects should be sufficiently considered in coastal development and management. Furthermore, in order to predict the future evolution of the S. alterniflora wetlands over the region, in addition to in situ monitoring and measurements, an ecosystem dynamic model should be established, taking into account the coupling of the rerrestrial and marine environmental-ecological processes.
基金Supported by the National High Technology Research and Development Program (863 Program) of China(No. 2007AA091702)the Open Foundation of Key Laboratory of Jiangsu Province, China (No. K04009)
文摘A sand culture experiment was conducted to determine the effects of different seawater (5% and 10%) treatments on plant growth,inorganic ions,indole alkaloid concentrations and yields of Catharanthus roseus,in an effort to increase the alkaloid yield by artificial cultivation.The total fresh and dry weights and tissue K + concentrations decreased,but Na + concentrations increased in the plant roots,stems and leaves of C.roseus under seawater stress as compared to the control.The concentrations and yields of vindoline,catharanthine,vinblastine and vincristine increased under seawater stress.The concentrations and yields of these alkaloids were higher in 5% seawater-treated plants than those in the 10% seawater-treated plants.Considering the industrial production,5% seawater treatments could reduce the cost of producing alkaloid.In the control plants,the highest alkaloid concentrations reached a peak at 100 days after planting,suggesting that plant harvest must be optimized in terms of growth duration.
基金National Natural Science Foundation of China(41171083/U1203181)
文摘Research for changes of soil water and salt is an important content of land sciences and agriculture sciences in arid and semi arid regions. In this paper, sampling in actual agricultural fields, laboratory analysis of soil samples and statistical analysis methods are used to quantitatively analyze soil salinity changes under different ir- rigation methods throughout the cotton growing season in Shihezi reclamation area. The results show that irrigation methods play an important role in soil salt content in the surface soil (0-20 cm) and sub-deep soil (40-60 cm), fol- lowed by deep soil layer (60-100 cm) and root soil layer (20-40 cm). Furrow irrigation yields the maximum soil salt content in deep layer (60-100 cm) or sub-deep layer (40-60 cm) and the maximum salinity occurs in the first half of the cotton growing season (June or earlier). In contrast, drip irrigation yields the maximum soil salinity in the root layer (20-40 cm) or sub-deep (40-60 cm), and this usually appears in the second half growing season (July or af- ter). The ratio of chloride ion to sulfate ion (Cl-/SO2- 4) and its change in the soil are on the rise under furrow irrigation while the value first increased and then decreased with a peak point in June under drip irrigation. This suggests that furrow irrigation may shift the type of soil salinization to chloride ion type moreso than drip irrigation. Potassium and sodium ion contents of the soil show that soil sodium+potassium content will drop after the first rise under furrow irrigation and the value is manifested by fluctuations under drip irrigation. Potassium+sodium content change is relatively more stable in the whole cotton growth period under irrigation methods. The maximum of sodium and potassium content of the soil usually occur in deep soil layer (60-100 cm) or sub-deep soil layer (40-60 cm) in most sample points under furrow irrigation while it is inconsistent in different sample points under drip irrigation. A non- parametric test for paired samples is used to analyze differences of soil salt content under different irrigation methods. This analysis shows that the impact of irrigation on soil salinity is most significant in July, followed by August, June, May, and April in most sample points. The most significant impact of irrigation methods occurs in the surface soil layer (0-20 cm), followed by deep layer (60-100 cm), root layer (20-40 cm) and sub-deep (40-60 cm). These conclusions will be benefitial for mitigation of soil salinization, irrigation and fertilization and sustainable land use.