The variation characteristics of acid rain and the relationship between the formation of acid rain and meteorological conditions were analyzed based on the observation data and meteorological records collected from ac...The variation characteristics of acid rain and the relationship between the formation of acid rain and meteorological conditions were analyzed based on the observation data and meteorological records collected from acid rain observation station in Dalian over 2006-2009.The results showed that Dalian was one of the regions with strong acid rain in northern China,with the frequency of 66% and pH value of 3.49.The acidity was the strongest in fall and weakest in spring;and the maximum and minimum frequencies were in summer and in winter respectively.Frequency of acid rain was inversely proportional to wind speed and concentration of inhalable particles in Dalian;acid rain occurred easily in foggy weather due to the steady stratification and abundant moisture;continuous precipitation did not mean the reduction of acidic material in the air,and the rainfall with increased acidity in the second day accounted for 42% in continuous precipitation cases.展开更多
The temporal-spatial distribution and seasonal variation of the precipitation acidity in Guangxi Province were statistically analyzed by means of the data from 2003 to 2008 in 10 Stations of Acid Rain Observation in t...The temporal-spatial distribution and seasonal variation of the precipitation acidity in Guangxi Province were statistically analyzed by means of the data from 2003 to 2008 in 10 Stations of Acid Rain Observation in the province and the data from 1996 to 2008 in two Monitoring Spots in Nanning and Baise,respectively.The results showed that annual average pH value of precipitation was <5.6 based on the analysis of the data from 10 Stations of Acid Rain Observation in the province,among which,the data from 5 stations indicated that annual average pH value of precipitation was <4.5.Thus,it can be thought that the serious acid rain had appeared in the province.There was an obvious seasonal variation in the extent of the acidity in precipitation and the acidity of precipitation in spring and winter was heavier than that in summer and autumn.展开更多
Environmental problem is one of three major issues of common concern in the world today.Being a developing socialist country,the environmental problems in china are even more prominent,mainly in population expansion,s...Environmental problem is one of three major issues of common concern in the world today.Being a developing socialist country,the environmental problems in china are even more prominent,mainly in population expansion,sharp decrease of global forest areas,soil erosion,acid rain pollution,water pollution and so on.This essay is to introduce the present status,formation causes and hazardous condition of acid rain pollution in china.Some feasible and effective control measures are put forward according to the actual situation in China.展开更多
In order to investigate the effect of acid rain on photosynthetic characteristics of spring wheat,spring wheat at the jointing stage was sprayed with simulated acid rain at different pH levels of 1.5,2.5,3.5,4.5 and 5...In order to investigate the effect of acid rain on photosynthetic characteristics of spring wheat,spring wheat at the jointing stage was sprayed with simulated acid rain at different pH levels of 1.5,2.5,3.5,4.5 and 5.6,and then,the photosynthetic parameters of spring wheat leaf was monitored.The results indicated that the pH value of simulated acid rain was positively and very significantly correlated with the net photosynthetic rate,stomata conductance,transpiration rate,water use efficiency and the chlorophyll relative content,whereas very significantly and negatively correlated with intercellular CO2 concentration.Due to acid rain,the net photosynthetic rate,stomata conductance,transpiration rate and the chlorophyll relative content decreased by 4.08%-67.04%,17.44%-58.44%,12.08%-48.08% and 12.16%-37.23% respectively,while intercellular CO2 concentration increased by 9.01%-14.29%.After simulated treatment with acid rain,the net photosynthetic rate had high significant positive correlation with stomata conductance,transpiration rate,water use efficiency,and the chlorophyll relative content,but high significant negative correlation with intercellular CO2 concentration.At the same time,transpiration rate was observed to be very significantly and positively correlated to stomata conductance and chlorophyll relative content,being significantly and positively correlated with water use efficiency,and very significantly and negatively correlated with intercellular CO2 concentration.In a word,the influence of simulated acid rain on photosynthetic characteristics of spring wheat leaf became more and more obvious with the increase of hydrogen ion concentration.展开更多
Based on the rainfall monitoring data and high altitude meteorological data,the present situation of acid rain pollution in Nanchang City was analyzed and the forming factors of acid rain were revealed. The results sh...Based on the rainfall monitoring data and high altitude meteorological data,the present situation of acid rain pollution in Nanchang City was analyzed and the forming factors of acid rain were revealed. The results showed that acid rain in Nanchang had the characteristics of high acidity and frequency,and the pH value of rainfall reduced in recent years,belonging to sulfuric acid type,and the most serious acid rain pollution appeared in autumn and winter. The pH value of rainfall went up with the improvement of rainfall grade,and the increase of rainfall quantity had diluting effect on the rainfall acidity. High altitude meteorological conditions affected acid rain obviously,when the upper wind velocity was below 7 m/s,the frequency of acid rain was higher and its pH value was lower,with serious acid rain pollution,and it showed that upper wind had diluting effect on the horizontal transport of pollutants. The frequency of acid rain became higher with stronger inversion intensity. Moreover,the surrounding industrial areas had obvious effect on the formation of acid rain. Unstable meteorological conditions were beneficial to the horizontal and vertical diffusion of pollution in the lower atmosphere,reducing the effect of induced-acidity pollutants on a region.展开更多
This paper describes a programme for controlling acld rain and SO2 pollutions in the coming years in China. It embraces the control targets in some respects, such as precipitation acidity, urban SO2 pollution, SO2 emi...This paper describes a programme for controlling acld rain and SO2 pollutions in the coming years in China. It embraces the control targets in some respects, such as precipitation acidity, urban SO2 pollution, SO2 emission sources and its total emission, and various control measures, such as limiting the exploitation of high sulfur coal, promoting steam coal washing, strengthening SO2 emission sources control and readjusting their special layout, enhancing total SO2 emission control, implementing the licence system of pollution discharge and the exchange system of SO2 emission and revising the SO2 emission standards.展开更多
Based on acid rain data from ten monitoring sites in Guangxi from 2003 to 2009,the temporal and spatial distribution characteristic of acid rain in Guangxi were analyzed by means of empirical orthogonal function resol...Based on acid rain data from ten monitoring sites in Guangxi from 2003 to 2009,the temporal and spatial distribution characteristic of acid rain in Guangxi were analyzed by means of empirical orthogonal function resolution(EOF).The results showed that there was fluctuating change of acid rain frequency in Guangxi,and acid rain pollution became severer in 2004-2008;acid rain frequency changed conformably in the whole region and it was obviously higher in eastern and northwestern Guangxi,while acid rain pollution became severe in western Guangxi;acid rain frequency varied out of phase between northeastern and southwestern Guangxi in an individual year.展开更多
Acid rain is a serious environmental problem worldwide. In this study, a pot experiment using forest soils planted with the seedlings of four woody species was performed with weekly treatments of pH 4.40, 4.00, 3.52, ...Acid rain is a serious environmental problem worldwide. In this study, a pot experiment using forest soils planted with the seedlings of four woody species was performed with weekly treatments of pH 4.40, 4.00, 3.52, and 3.05 simulated acid rain (SAR) for 42 months compared to a control of pH 5.00 lake water. The cumulative amounts of C and N mineralization in the five treated soils were determined after incubation at 25 ℃ for 65 d to examine the effects of SAR treatments. For all five treatments, cumulative CO2-C production ranged from 20.24 to 27.81 mg kg-1 dry soil, net production of available N from 17.37 to 48.95 mg kg-1 dry soil, and net production of NO-3 -N from 9.09 to 46.23 mg kg-1 dry soil. SAR treatments generally enhanced the emission of CO2-C from the soils; however, SAR with pH 3.05 inhibited the emission. SAR treatments decreased the net production of available N and NO3-N. The cumulative CH4 and N2O productions from the soils increased with increasing amount of simulated acid rain. The cumulative CO2-C production and the net production of available N of the soil under Acmena acuminatissima were significantly higher (P ≤ 0.05) than those under Schima superba and Cryptocarya concinna. The mineralization of soil organic C was related to the contents of soil organic C and N, but was not related to soil pH. However, the overall effect of acid rain on the storage of soil organic matter and the cycling of important nutrients depended on the amount of acid deposition and the types of forests.展开更多
The effects of lanthanum on some redox system(PMRS) properties of the plasma membrane(PM) vesicles from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5)stress were studied. The results show tha...The effects of lanthanum on some redox system(PMRS) properties of the plasma membrane(PM) vesicles from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5)stress were studied. The results show that there are NADH oxidase and EDTA Fe 3+ reductase, and nitrate reductase in the seedling PM, and they have different responses to soaking seeds for 8 h in a series of LaCl 3 solution. The NADH oxidase activities and the Nitrate reductase activities can be stimulated when La 3+ concentrations is in the range of 50～200 mg·L -1 , but their activities are inhibited or fluctuate by the higher La 3+ concentrations. The EDTA Fe 3+ reductase activities can be stimulated by La 3+ concentrations in the range of 50～400 mg·L -1 . The research also revealed that La 3+ reduces the relative permeability of membranes and have the function in protecting membranes under acid rain stress by the way of inhibiting the leakage of electrolyte.展开更多
The effects of La^(3+) on the growth and the ATPases activities of plasma membrane(PM) vesicles isolated from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5) stress were studied. The results show ...The effects of La^(3+) on the growth and the ATPases activities of plasma membrane(PM) vesicles isolated from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5) stress were studied. The results show that the height, length of roots, fresh weight and PM H^+-ATPase activites of Casuarina equisetifolia seedlings increase by the treatments of soaking seeds in LaCl_3 solutions with lower concentrations, and those can reach their peak values by treating with 200 mg·L^(-1) La^(3+). However, in comparison with the CK, those are inhibited by the higher La^(3+) concentrations; PM Ca^(2+)-ATPase activity is inhibited with the treatments of La^(3+). The results also reveal that the H^+-ATPase activity and the growth of cell enlarge have a remarkable positive correlation, and La^(3+) activating H^+-ATPase can facilitate plant growth. La^(3+) also can alleviate cytosolic acidification of plant under acid rain stress and indirectly maintain the stability of intracellular environment. In order to resistant to acid rain and accelerate the growth of Casuarina equisetifolia, the suitable range of La^(3+) concentrations to soak seeds for 8 h is 50～200 mg·L^(-1).展开更多
The content and distribution characteristics of REE in spinach and soil under using REE and acid rain stress were studied by pot experiments. The results show that the content of REE is 0 527～0 696 (μg·g -...The content and distribution characteristics of REE in spinach and soil under using REE and acid rain stress were studied by pot experiments. The results show that the content of REE is 0 527～0 696 (μg·g -1 ) in the above ground portion of spinach, 2 668～3 003 (μg·g -1 ) in the under ground portion of spinach and 229 09～250 30 (μg·g -1 ) in the soil. With the acidity of acid rain increasing, the leaching of REE in plants and soil is strengthened and the amount of REE reduces with decreasing of pH value. After REE are used, though plants show the selective absorption to Ce group elements (especially spraying on leaves), regardless under acid rain stress or using REE or not, the distribution model of REE in the above ground and under ground portion of plants is basically the same with the control. Plants also follow the Oddo Harkins rule of the REE of distribution abundance, light rare earth elements is enriched, the minus of Eu is abnormal and admeasure of Ce is a rich model. The results show that REE in plants mainly come from soil and are affected by it.展开更多
The regulatory role of calcium in fertility of pollen and pistil under simulated acid rain was investigated. The germination percentage of pollen treated with acid rain of pH 4.5 was 9.42% lower than that of control, ...The regulatory role of calcium in fertility of pollen and pistil under simulated acid rain was investigated. The germination percentage of pollen treated with acid rain of pH 4.5 was 9.42% lower than that of control, and that of pH 3.5, pH 2.5 and pH 1.5 were 22.47%, 45.49% and 71.62%, respectively. Simultaneously, the injury character of pollen was obviously observed when flowers were treated with acid rain of pH 3.5. The difference in fruit setting rate between the female flower treated with acid rain of pH 4.0 and the control was significant at p 〈 0.05. Ca（NO3 ）5 of 0.2-0.4 mmol/L could promote pollen germination under the stress of acid rain. The beneficial function was reduced when calcium concentration surpassed 0.8 mmol/L. Spraying 2 mmol/L Ca（NO3 ）5 reduced the injury of acid rain to pistil and increased fruit-setting rate significantly. The physiological importance of calcium during pollen germination and pistil development was also discussed.展开更多
Effects of the simulated acid rain（AR） and ultraviolet-B（UV-B, 280-320 nm） radiation with a single or two ways simultaneously （AR ＋ UV-B） on the antioxidant enzyme and photosynthesis of the rape seedlings were ...Effects of the simulated acid rain（AR） and ultraviolet-B（UV-B, 280-320 nm） radiation with a single or two ways simultaneously （AR ＋ UV-B） on the antioxidant enzyme and photosynthesis of the rape seedlings were investigated by the hydroponic culture. The results of static experiment indicated that the tolerance of rape seedling to single stress（AR or UV-B） is stronger than that to dual stresses（AR ＋ UV-B）. Furthermore, the dual stresses had additive effect on catalase activity, and a synergistic effect on MDA content, net photosynthesis rate, water use efficiency as well as intercellular CO2 concentration. Meanwhile, it has an independent effect on chlorophyll content, stomatal conductance, and transpiration rate as well as membrane permeability. During 64 h restoration course, the dynamic change in the curves of physiological and biochemical indices were not identical, and none of them show a simple linear variation. According to the static and dynamic experiments, it was found that a responsive sequence of catalase activity, membrane permeability, MDA content and photosynthetic characteristics to the above-mentioned stresses was as follows： AR ＋ UV-B 〉 UV-B 〉 AR.展开更多
Several factors, namely, coal dominated primary energy mix, extensive economic development mode, inefficient energy utilization, and the imperfect environmental regulations, result in the serious urban sulfur dioxide...Several factors, namely, coal dominated primary energy mix, extensive economic development mode, inefficient energy utilization, and the imperfect environmental regulations, result in the serious urban sulfur dioxide pollution and large scale sulfate type acid precipitation in China. In 1995, China′s sulfur dioxide emissions reached 23.70 Mt, and the areas affected by acid rain accounted for 40% of the territory. Chinese government accords considerable importance to the sulfur dioxide and acid rain contamination. New sets of environmental friendly policies have been promulgated. But enforcement of laws and regulations on SO 2 emissions need to be further improved and broadened, especially those respond to market conditions. This paper focuses particular attention on the analysis of strategy, policies, and national actions which had or should be taken against sulfur dioxide emissions nationwide to achieve the environmental targets, on the basis of which gives the technical options in future.展开更多
Effect of Ce on barley seed germination under acid rain stress was studied. The experiment results show that the seed germination percentage, germination viability, dry weight of seedling and chlorophyll content decre...Effect of Ce on barley seed germination under acid rain stress was studied. The experiment results show that the seed germination percentage, germination viability, dry weight of seedling and chlorophyll content decrease with increasing pH value, but root membrane permeability increases with decreasing acid rain pH value. Ce can reduce the acid rain stress when barley seed is soaked with Ce. It indicates that Ce mitigates the germination by acid rain inhibition of seed.展开更多
Acid rain can deteriorate the performance of reinforced concrete structure.Combined with the characteristics of acid rain in China,the properties of steel fiber reinforced concrete subjected to acid rain were studied....Acid rain can deteriorate the performance of reinforced concrete structure.Combined with the characteristics of acid rain in China,the properties of steel fiber reinforced concrete subjected to acid rain were studied.The effects of steel fiber content and pH value of acid rain on the mass loss,erosion depth,neutralization depth,and splitting tensile strength of tested concrete were investigated.The mercury intrusion pore（MIP） test was used to analyze the influence of steel fiber on the acid rain resistance of concrete matrix.The results show that the corrosion of steel fiber reinforced concrete subjected to acid rain results from the combined effect of H^＋ and SO4^2- in the acid rain,and steel fiber can improve the acid rain resistance of the tested concrete by improving the pore structure and enhancing the tie effect of the concrete matrix.The experiment further indicates that the optimum content of steel fiber is 1.5%compared to the various mixing proportion in this tests.The tested concrete mass loss and splitting tensile strength decrease followed by increasing as a function of corrosion time when the pH value of the simulation solution is 3 or 4,while they decrease continuously in the simulation solution at pH 2.Thanks to the tie effect of steel fiber,the spalling of concrete matrix is significantly improved,and the erosion depth and neutralization depth are less than those of conventional concrete.展开更多
Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the ...Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the results indicate that Pr(Ⅲ) interacts with MP11, increasing the non planarity of porphyrin periphery, leading MP11 to form two conformations when titrated by Pr(Ⅲ). Excessive Pr(Ⅲ) acts as a contaminant in living organism. H + and Pr(Ⅲ) have antagonistic effect on MP11, suggesting that at suitable concentration under physiological conditions, Pr(Ⅲ) can be used as biomodulator in protecting plants from acid rain stress or in rehabilitating the harm.展开更多
Acid rain has been recognized as a serious environmental problem in China since the 1980s, but little is known about the effects of the climatic change in regional precipitation on the temporal and spatial variability...Acid rain has been recognized as a serious environmental problem in China since the 1980s, but little is known about the effects of the climatic change in regional precipitation on the temporal and spatial variability of severe acid rain. We present the effects of the regional precipitation trend change on the area and intensity of severe acid rain in southern China, and the spatio-temporal distribution characteristics of SO2 and NO2 concentrations are analyzed on the basis of SO2 and NO2 column concentration data. The results are as follows. （1） The emission levels of SO2 and NO2 have reached or passed the precipitation scavenging capacity in parts of southern China owing to the emission totals of SOz and NO2 increasing from 1993 to 2004. （2） Notable changes in the proportion of cities subject to severe acid rain occurred mainly in the south of the middle-lower reaches of the Yangtze River during 1993-2004. With an abrupt change in 1999, the severe acid rain regions were mainly located in central and western China during 1993-1999 and moved obviously eastward to the south of the lower-middle reaches of the Yangtze River with the proportion of cities subject to severe acid rain increasing significantly from 2000 to 2004. （3） The spatial distribution and variation in the seasonal precipitation change rate of more than 10 mm/10a are similar to those of severe acid rain in southern China. An abrupt change in 1999 is seen for winter and summer precipitation, the same as for the proportion of cities subject to severe acid rain in southern China. The significant increase in summer storm precipitation from 1991 to 1999 mitigated the annual precipitation acidity in the south of the Yangtze River and reduced the area of severe acid rainfall. On the other hand, the decrease in storm rainfall in summer expanded the area of severe acid rainfall in the south of the Yangtze River in 2000-2006. Therefore, the change in seasonal precipitation is an important factor in the severe acid rain regions moving eastward and expanding in southern China.展开更多
To predict the economic loss of crops caused by acid rain,we used partial least squares(PLS) regression to build a model of single dependent variable -the economic loss calculated with the decrease in yield related to...To predict the economic loss of crops caused by acid rain,we used partial least squares(PLS) regression to build a model of single dependent variable -the economic loss calculated with the decrease in yield related to the pH value and levels of Ca2+,NH4+,Na+,K+,Mg2+,SO42-,NO3-,and Cl-in acid rain. We selected vegetables which were sensitive to acid rain as the sample crops,and collected 12 groups of data,of which 8 groups were used for modeling and 4 groups for testing. Using the cross validation method to evaluate the performace of this prediction model indicates that the optimum number of principal components was 3,determined by the minimum of prediction residual error sum of squares,and the prediction error of the regression equation ranges from -2.25% to 4.32%. The model predicted that the economic loss of vegetables from acid rain is negatively corrrelated to pH and the concentrations of NH4+,SO42-,NO3-,and Cl-in the rain,and positively correlated to the concentrations of Ca2+,Na+,K+ and Mg2+. The precision of the model may be improved if the non-linearity of original data is addressed.展开更多
Seeds and seedlings of five broad-leaved species were separately exposed to simulated acid rain at pH values of 2.0, 3.5, 5.0, and 6.0, or to distilled water (the control). The results showed that seed germination was...Seeds and seedlings of five broad-leaved species were separately exposed to simulated acid rain at pH values of 2.0, 3.5, 5.0, and 6.0, or to distilled water (the control). The results showed that seed germination was remarkably inhibited by pH 2.0 treatment for three species. Significant foliar damage, decline in chlorophyll contents, and retardation of the seedlings growth of all the species, were observed at pH 2.0 treatment. The pH 2.0 treatment seemed to be a threshold level for inhibition of seed germination and seedling growth for all the treated species, while seedling was stimulated at pH value between 3.5 and 5.0.展开更多
基金Supported by Scientific Research Special Fund for Public Welfare Industry (Meteorology) (GYHY20080620)
文摘The variation characteristics of acid rain and the relationship between the formation of acid rain and meteorological conditions were analyzed based on the observation data and meteorological records collected from acid rain observation station in Dalian over 2006-2009.The results showed that Dalian was one of the regions with strong acid rain in northern China,with the frequency of 66% and pH value of 3.49.The acidity was the strongest in fall and weakest in spring;and the maximum and minimum frequencies were in summer and in winter respectively.Frequency of acid rain was inversely proportional to wind speed and concentration of inhalable particles in Dalian;acid rain occurred easily in foggy weather due to the steady stratification and abundant moisture;continuous precipitation did not mean the reduction of acidic material in the air,and the rainfall with increased acidity in the second day accounted for 42% in continuous precipitation cases.
文摘The temporal-spatial distribution and seasonal variation of the precipitation acidity in Guangxi Province were statistically analyzed by means of the data from 2003 to 2008 in 10 Stations of Acid Rain Observation in the province and the data from 1996 to 2008 in two Monitoring Spots in Nanning and Baise,respectively.The results showed that annual average pH value of precipitation was <5.6 based on the analysis of the data from 10 Stations of Acid Rain Observation in the province,among which,the data from 5 stations indicated that annual average pH value of precipitation was <4.5.Thus,it can be thought that the serious acid rain had appeared in the province.There was an obvious seasonal variation in the extent of the acidity in precipitation and the acidity of precipitation in spring and winter was heavier than that in summer and autumn.
文摘Environmental problem is one of three major issues of common concern in the world today.Being a developing socialist country,the environmental problems in china are even more prominent,mainly in population expansion,sharp decrease of global forest areas,soil erosion,acid rain pollution,water pollution and so on.This essay is to introduce the present status,formation causes and hazardous condition of acid rain pollution in china.Some feasible and effective control measures are put forward according to the actual situation in China.
基金Supported by Scientific Research Special Fund for Public Welfare Industry (Meteorology) (GY-HY200806021)Drought Fund Project of Lanzhou Arid Meteorology Institute,China Meteorological Administration (IAM200921)
文摘In order to investigate the effect of acid rain on photosynthetic characteristics of spring wheat,spring wheat at the jointing stage was sprayed with simulated acid rain at different pH levels of 1.5,2.5,3.5,4.5 and 5.6,and then,the photosynthetic parameters of spring wheat leaf was monitored.The results indicated that the pH value of simulated acid rain was positively and very significantly correlated with the net photosynthetic rate,stomata conductance,transpiration rate,water use efficiency and the chlorophyll relative content,whereas very significantly and negatively correlated with intercellular CO2 concentration.Due to acid rain,the net photosynthetic rate,stomata conductance,transpiration rate and the chlorophyll relative content decreased by 4.08%-67.04%,17.44%-58.44%,12.08%-48.08% and 12.16%-37.23% respectively,while intercellular CO2 concentration increased by 9.01%-14.29%.After simulated treatment with acid rain,the net photosynthetic rate had high significant positive correlation with stomata conductance,transpiration rate,water use efficiency,and the chlorophyll relative content,but high significant negative correlation with intercellular CO2 concentration.At the same time,transpiration rate was observed to be very significantly and positively correlated to stomata conductance and chlorophyll relative content,being significantly and positively correlated with water use efficiency,and very significantly and negatively correlated with intercellular CO2 concentration.In a word,the influence of simulated acid rain on photosynthetic characteristics of spring wheat leaf became more and more obvious with the increase of hydrogen ion concentration.
基金Supported by Major Project of Chinese National Program for Fundamental Research and Development("973" Program)(2005CB42- 208)Meteorological Science and Technology Innovation Foundation of Jiangxi Province,China(2006KJC-X1006)
文摘Based on the rainfall monitoring data and high altitude meteorological data,the present situation of acid rain pollution in Nanchang City was analyzed and the forming factors of acid rain were revealed. The results showed that acid rain in Nanchang had the characteristics of high acidity and frequency,and the pH value of rainfall reduced in recent years,belonging to sulfuric acid type,and the most serious acid rain pollution appeared in autumn and winter. The pH value of rainfall went up with the improvement of rainfall grade,and the increase of rainfall quantity had diluting effect on the rainfall acidity. High altitude meteorological conditions affected acid rain obviously,when the upper wind velocity was below 7 m/s,the frequency of acid rain was higher and its pH value was lower,with serious acid rain pollution,and it showed that upper wind had diluting effect on the horizontal transport of pollutants. The frequency of acid rain became higher with stronger inversion intensity. Moreover,the surrounding industrial areas had obvious effect on the formation of acid rain. Unstable meteorological conditions were beneficial to the horizontal and vertical diffusion of pollution in the lower atmosphere,reducing the effect of induced-acidity pollutants on a region.
文摘This paper describes a programme for controlling acld rain and SO2 pollutions in the coming years in China. It embraces the control targets in some respects, such as precipitation acidity, urban SO2 pollution, SO2 emission sources and its total emission, and various control measures, such as limiting the exploitation of high sulfur coal, promoting steam coal washing, strengthening SO2 emission sources control and readjusting their special layout, enhancing total SO2 emission control, implementing the licence system of pollution discharge and the exchange system of SO2 emission and revising the SO2 emission standards.
基金Supported by Scientific Research and Technological Development Planning Project of Guangxi Province(10123009-9)~~
文摘Based on acid rain data from ten monitoring sites in Guangxi from 2003 to 2009,the temporal and spatial distribution characteristic of acid rain in Guangxi were analyzed by means of empirical orthogonal function resolution(EOF).The results showed that there was fluctuating change of acid rain frequency in Guangxi,and acid rain pollution became severer in 2004-2008;acid rain frequency changed conformably in the whole region and it was obviously higher in eastern and northwestern Guangxi,while acid rain pollution became severe in western Guangxi;acid rain frequency varied out of phase between northeastern and southwestern Guangxi in an individual year.
基金the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KSCX2-SW-120)the National Natural Science Foundation of China (No. 30470306)
文摘Acid rain is a serious environmental problem worldwide. In this study, a pot experiment using forest soils planted with the seedlings of four woody species was performed with weekly treatments of pH 4.40, 4.00, 3.52, and 3.05 simulated acid rain (SAR) for 42 months compared to a control of pH 5.00 lake water. The cumulative amounts of C and N mineralization in the five treated soils were determined after incubation at 25 ℃ for 65 d to examine the effects of SAR treatments. For all five treatments, cumulative CO2-C production ranged from 20.24 to 27.81 mg kg-1 dry soil, net production of available N from 17.37 to 48.95 mg kg-1 dry soil, and net production of NO-3 -N from 9.09 to 46.23 mg kg-1 dry soil. SAR treatments generally enhanced the emission of CO2-C from the soils; however, SAR with pH 3.05 inhibited the emission. SAR treatments decreased the net production of available N and NO3-N. The cumulative CH4 and N2O productions from the soils increased with increasing amount of simulated acid rain. The cumulative CO2-C production and the net production of available N of the soil under Acmena acuminatissima were significantly higher (P ≤ 0.05) than those under Schima superba and Cryptocarya concinna. The mineralization of soil organic C was related to the contents of soil organic C and N, but was not related to soil pH. However, the overall effect of acid rain on the storage of soil organic matter and the cycling of important nutrients depended on the amount of acid deposition and the types of forests.
文摘The effects of lanthanum on some redox system(PMRS) properties of the plasma membrane(PM) vesicles from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5)stress were studied. The results show that there are NADH oxidase and EDTA Fe 3+ reductase, and nitrate reductase in the seedling PM, and they have different responses to soaking seeds for 8 h in a series of LaCl 3 solution. The NADH oxidase activities and the Nitrate reductase activities can be stimulated when La 3+ concentrations is in the range of 50～200 mg·L -1 , but their activities are inhibited or fluctuate by the higher La 3+ concentrations. The EDTA Fe 3+ reductase activities can be stimulated by La 3+ concentrations in the range of 50～400 mg·L -1 . The research also revealed that La 3+ reduces the relative permeability of membranes and have the function in protecting membranes under acid rain stress by the way of inhibiting the leakage of electrolyte.
文摘The effects of La^(3+) on the growth and the ATPases activities of plasma membrane(PM) vesicles isolated from Casuarina equisetifolia seedlings under artificial acid rain(pH 4.5) stress were studied. The results show that the height, length of roots, fresh weight and PM H^+-ATPase activites of Casuarina equisetifolia seedlings increase by the treatments of soaking seeds in LaCl_3 solutions with lower concentrations, and those can reach their peak values by treating with 200 mg·L^(-1) La^(3+). However, in comparison with the CK, those are inhibited by the higher La^(3+) concentrations; PM Ca^(2+)-ATPase activity is inhibited with the treatments of La^(3+). The results also reveal that the H^+-ATPase activity and the growth of cell enlarge have a remarkable positive correlation, and La^(3+) activating H^+-ATPase can facilitate plant growth. La^(3+) also can alleviate cytosolic acidification of plant under acid rain stress and indirectly maintain the stability of intracellular environment. In order to resistant to acid rain and accelerate the growth of Casuarina equisetifolia, the suitable range of La^(3+) concentrations to soak seeds for 8 h is 50～200 mg·L^(-1).
文摘The content and distribution characteristics of REE in spinach and soil under using REE and acid rain stress were studied by pot experiments. The results show that the content of REE is 0 527～0 696 (μg·g -1 ) in the above ground portion of spinach, 2 668～3 003 (μg·g -1 ) in the under ground portion of spinach and 229 09～250 30 (μg·g -1 ) in the soil. With the acidity of acid rain increasing, the leaching of REE in plants and soil is strengthened and the amount of REE reduces with decreasing of pH value. After REE are used, though plants show the selective absorption to Ce group elements (especially spraying on leaves), regardless under acid rain stress or using REE or not, the distribution model of REE in the above ground and under ground portion of plants is basically the same with the control. Plants also follow the Oddo Harkins rule of the REE of distribution abundance, light rare earth elements is enriched, the minus of Eu is abnormal and admeasure of Ce is a rich model. The results show that REE in plants mainly come from soil and are affected by it.
文摘The regulatory role of calcium in fertility of pollen and pistil under simulated acid rain was investigated. The germination percentage of pollen treated with acid rain of pH 4.5 was 9.42% lower than that of control, and that of pH 3.5, pH 2.5 and pH 1.5 were 22.47%, 45.49% and 71.62%, respectively. Simultaneously, the injury character of pollen was obviously observed when flowers were treated with acid rain of pH 3.5. The difference in fruit setting rate between the female flower treated with acid rain of pH 4.0 and the control was significant at p 〈 0.05. Ca（NO3 ）5 of 0.2-0.4 mmol/L could promote pollen germination under the stress of acid rain. The beneficial function was reduced when calcium concentration surpassed 0.8 mmol/L. Spraying 2 mmol/L Ca（NO3 ）5 reduced the injury of acid rain to pistil and increased fruit-setting rate significantly. The physiological importance of calcium during pollen germination and pistil development was also discussed.
文摘Effects of the simulated acid rain（AR） and ultraviolet-B（UV-B, 280-320 nm） radiation with a single or two ways simultaneously （AR ＋ UV-B） on the antioxidant enzyme and photosynthesis of the rape seedlings were investigated by the hydroponic culture. The results of static experiment indicated that the tolerance of rape seedling to single stress（AR or UV-B） is stronger than that to dual stresses（AR ＋ UV-B）. Furthermore, the dual stresses had additive effect on catalase activity, and a synergistic effect on MDA content, net photosynthesis rate, water use efficiency as well as intercellular CO2 concentration. Meanwhile, it has an independent effect on chlorophyll content, stomatal conductance, and transpiration rate as well as membrane permeability. During 64 h restoration course, the dynamic change in the curves of physiological and biochemical indices were not identical, and none of them show a simple linear variation. According to the static and dynamic experiments, it was found that a responsive sequence of catalase activity, membrane permeability, MDA content and photosynthetic characteristics to the above-mentioned stresses was as follows： AR ＋ UV-B 〉 UV-B 〉 AR.
文摘Several factors, namely, coal dominated primary energy mix, extensive economic development mode, inefficient energy utilization, and the imperfect environmental regulations, result in the serious urban sulfur dioxide pollution and large scale sulfate type acid precipitation in China. In 1995, China′s sulfur dioxide emissions reached 23.70 Mt, and the areas affected by acid rain accounted for 40% of the territory. Chinese government accords considerable importance to the sulfur dioxide and acid rain contamination. New sets of environmental friendly policies have been promulgated. But enforcement of laws and regulations on SO 2 emissions need to be further improved and broadened, especially those respond to market conditions. This paper focuses particular attention on the analysis of strategy, policies, and national actions which had or should be taken against sulfur dioxide emissions nationwide to achieve the environmental targets, on the basis of which gives the technical options in future.
文摘Effect of Ce on barley seed germination under acid rain stress was studied. The experiment results show that the seed germination percentage, germination viability, dry weight of seedling and chlorophyll content decrease with increasing pH value, but root membrane permeability increases with decreasing acid rain pH value. Ce can reduce the acid rain stress when barley seed is soaked with Ce. It indicates that Ce mitigates the germination by acid rain inhibition of seed.
基金Funded by National Natural Science Foundation of China(No.51380445)Natural Science Foundation of Shan’xi Province,China(No.2013JQ7033)Startup Foundation for Talents of Xi’an University of Architecture and Technology(No.DB 09077)
文摘Acid rain can deteriorate the performance of reinforced concrete structure.Combined with the characteristics of acid rain in China,the properties of steel fiber reinforced concrete subjected to acid rain were studied.The effects of steel fiber content and pH value of acid rain on the mass loss,erosion depth,neutralization depth,and splitting tensile strength of tested concrete were investigated.The mercury intrusion pore（MIP） test was used to analyze the influence of steel fiber on the acid rain resistance of concrete matrix.The results show that the corrosion of steel fiber reinforced concrete subjected to acid rain results from the combined effect of H^＋ and SO4^2- in the acid rain,and steel fiber can improve the acid rain resistance of the tested concrete by improving the pore structure and enhancing the tie effect of the concrete matrix.The experiment further indicates that the optimum content of steel fiber is 1.5%compared to the various mixing proportion in this tests.The tested concrete mass loss and splitting tensile strength decrease followed by increasing as a function of corrosion time when the pH value of the simulation solution is 3 or 4,while they decrease continuously in the simulation solution at pH 2.Thanks to the tie effect of steel fiber,the spalling of concrete matrix is significantly improved,and the erosion depth and neutralization depth are less than those of conventional concrete.
文摘Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the results indicate that Pr(Ⅲ) interacts with MP11, increasing the non planarity of porphyrin periphery, leading MP11 to form two conformations when titrated by Pr(Ⅲ). Excessive Pr(Ⅲ) acts as a contaminant in living organism. H + and Pr(Ⅲ) have antagonistic effect on MP11, suggesting that at suitable concentration under physiological conditions, Pr(Ⅲ) can be used as biomodulator in protecting plants from acid rain stress or in rehabilitating the harm.
基金Concentrated fund item of national science and technology foundation work, No.2005DKA31700-06-20Special fund from China Meteorological Administration,No.CCSF2006-32
文摘Acid rain has been recognized as a serious environmental problem in China since the 1980s, but little is known about the effects of the climatic change in regional precipitation on the temporal and spatial variability of severe acid rain. We present the effects of the regional precipitation trend change on the area and intensity of severe acid rain in southern China, and the spatio-temporal distribution characteristics of SO2 and NO2 concentrations are analyzed on the basis of SO2 and NO2 column concentration data. The results are as follows. （1） The emission levels of SO2 and NO2 have reached or passed the precipitation scavenging capacity in parts of southern China owing to the emission totals of SOz and NO2 increasing from 1993 to 2004. （2） Notable changes in the proportion of cities subject to severe acid rain occurred mainly in the south of the middle-lower reaches of the Yangtze River during 1993-2004. With an abrupt change in 1999, the severe acid rain regions were mainly located in central and western China during 1993-1999 and moved obviously eastward to the south of the lower-middle reaches of the Yangtze River with the proportion of cities subject to severe acid rain increasing significantly from 2000 to 2004. （3） The spatial distribution and variation in the seasonal precipitation change rate of more than 10 mm/10a are similar to those of severe acid rain in southern China. An abrupt change in 1999 is seen for winter and summer precipitation, the same as for the proportion of cities subject to severe acid rain in southern China. The significant increase in summer storm precipitation from 1991 to 1999 mitigated the annual precipitation acidity in the south of the Yangtze River and reduced the area of severe acid rainfall. On the other hand, the decrease in storm rainfall in summer expanded the area of severe acid rainfall in the south of the Yangtze River in 2000-2006. Therefore, the change in seasonal precipitation is an important factor in the severe acid rain regions moving eastward and expanding in southern China.
基金Funded by the Natural Basic Research Program of China under the grant No. 2005CB422207.
文摘To predict the economic loss of crops caused by acid rain,we used partial least squares(PLS) regression to build a model of single dependent variable -the economic loss calculated with the decrease in yield related to the pH value and levels of Ca2+,NH4+,Na+,K+,Mg2+,SO42-,NO3-,and Cl-in acid rain. We selected vegetables which were sensitive to acid rain as the sample crops,and collected 12 groups of data,of which 8 groups were used for modeling and 4 groups for testing. Using the cross validation method to evaluate the performace of this prediction model indicates that the optimum number of principal components was 3,determined by the minimum of prediction residual error sum of squares,and the prediction error of the regression equation ranges from -2.25% to 4.32%. The model predicted that the economic loss of vegetables from acid rain is negatively corrrelated to pH and the concentrations of NH4+,SO42-,NO3-,and Cl-in the rain,and positively correlated to the concentrations of Ca2+,Na+,K+ and Mg2+. The precision of the model may be improved if the non-linearity of original data is addressed.
文摘Seeds and seedlings of five broad-leaved species were separately exposed to simulated acid rain at pH values of 2.0, 3.5, 5.0, and 6.0, or to distilled water (the control). The results showed that seed germination was remarkably inhibited by pH 2.0 treatment for three species. Significant foliar damage, decline in chlorophyll contents, and retardation of the seedlings growth of all the species, were observed at pH 2.0 treatment. The pH 2.0 treatment seemed to be a threshold level for inhibition of seed germination and seedling growth for all the treated species, while seedling was stimulated at pH value between 3.5 and 5.0.
