The feasibility of steel slag used as an iron fertilizer was studied in a pot experiment with corn. Slag alone or acidified slag was added to two Fe-deficient calcareous soils at different rates. Results showed that m...The feasibility of steel slag used as an iron fertilizer was studied in a pot experiment with corn. Slag alone or acidified slag was added to two Fe-deficient calcareous soils at different rates. Results showed that moderate rates (10 and 20 g kg-1) of slag or acidified slag substantially increased corn dry matter yield and Fe uptake. Application of steel slag increased the residual concentration of ammonium bicarbonate-diethylenetriamine pentaacetic acid (AB-DTPA) extractable Fe in the soils. The increase of extractable Fe was usually proportional to the application rate, and enhanced by the acidification of slag. Steel slag appeared to be a promising and inexpensive source of Fe to alleviate crop Fe chlorosis in Fe-deficient calcareous soils.展开更多
Water is the source of life. China ranks No.13 among the water shortage countries. The most of the water is utilized in agriculture, while the utilization rate of irrigation water is only 40%, so it is very important ...Water is the source of life. China ranks No.13 among the water shortage countries. The most of the water is utilized in agriculture, while the utilization rate of irrigation water is only 40%, so it is very important to study on the theory and technology on high efficient water utilization. The purpose for this study is to find out the optimal drainage line on potted flowers through the analysis of experimental results of Aglaonema modestum and Rhododendron simsii Planch in different drainage lines.展开更多
[Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetat...[Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetate copolymer and hydroxyl-modi- fied VCNAc were taken as coating materials to prepare slow release fertilizer. Nutri- ent release characteristics of VC/VAc slow release fertilizer was evaluated by water immersion method and the effects of VC/VAc slow release fertilizer on mineral ni- trogen were researched by pot experiment. [Result] The release periods of VC-VAc controlled-release urea and hydroxyl-modified VC/VAc coated urea were 60 and 50 d, respectively. Furthermore, the content of ammonium nitrogen reached the peak on the 30th d and the content of nitrate nitrogen reached the peak on the 60th d in soils in treatments with VCNAc and hydroxyl-modified VC/VAc; the content of nitrate nitrogen rose again on the 120th d in the treatment with VC/VAc. In terms of wheat yield, different treatments showed insignificant differences and rice yield in the treatment with VCNAc was significantly higher than that in the treatment with hy- droxyl-modified VCNAc (P〈0.05). [Conclusion] The release days of slow controlled- release fertilizer vary upon pot experiment method and water immersion method. Slow controlled-release fertilizer is not suitable for monoculture, due to long fertilizer efficiency, but multiple cropping would be optimal for its role to be fully exploited.展开更多
In order to better understand land application of sewage sludge, the characterization of heavy metals and organic pollutants were investigated in three different sewage sludges in Shanghai City, China. It was found th...In order to better understand land application of sewage sludge, the characterization of heavy metals and organic pollutants were investigated in three different sewage sludges in Shanghai City, China. It was found that the total concentrations of Cd in all of sewage sludge and total concentrations of Zn in Jinshan sewage sludge, as well as those ofZn, Cu, and Ni in Taopu sludge are higher than Chinese regulation limit of pollutants for sludge to be used in agriculture. Leachability of rig in all of studied samples and that of Cd in Taopu sewage sludge exceed the limit values of waste solid extraction standard in China legislation. Based on the characteristics for three kinds of sewage sludge, a pot experiment was conducted to investigate the effect of soil amended with Quyang sewage sludge on the accumulation of heavy metalo.by Begonia semperfloreas-hybr; Ophiopogon japonicas (L.F.) Ker-Gaw; Loropetalum chindense-var, rubrum; Dendranthema morifolium; Viola tricolor; A ntirrhinum majas; Buxas radicans Sieb; Viburnum macrocephalum; Osmanthas fragrans Lour; Cinnamomum camphora siebold and Ligustrum lucidum ait. Results showed that 8 species of plant survived in the amended soil, and moreover they flourished as well as those cultivated in the control soil. The heavy metal concentration in plants varied with species, As, Pb, Cd and Cr concentration being the highest in the four herbaceous species studied, particularly in the roots of D. morifolium. These plants, however, did not show accumulator of As, Pb, Cd and Cr. The highest concentration of Ni and Hg was found in the roots ofD. morifolium, followed by the leaves ofB. semperflorens-hybr. Levels of Zn and Cu were much higher in D. morifolium than in the other plant species. D. morifolium accumulated Ni, Hg, Cu and Zn, which may contribute to the decrease of heavy metal contents in the amended soil. Treatment with sewage sludge did not significantly affect the uptake of heavy metals by the L. chindense-var, rubrum, however, it significantly affected the uptake of heavy metals by D. morifolium.展开更多
Accumulation and fractionation of rare earth elements (REEs) were studied through applications of exogenous REEs in soils with pot-cultured rice for 2 years. The results show that the biomass of rice consistently de...Accumulation and fractionation of rare earth elements (REEs) were studied through applications of exogenous REEs in soils with pot-cultured rice for 2 years. The results show that the biomass of rice consistently decreases at sprouting and maturity stages when the amount of exogenous REEs are over 400 mg· kg^- 1. It illustrates that the endurance of rice to exogenous REE exposure is much weaker than that of wheat. The distribution patterns of REEs in rice of the control are similar to that in the soil, both exhibiting light REE (LREE) enrichment and positive Tb in the roots and the aboveground parts. Applications of exogenous REEs ranging from 400 to 1200 mg· kg^- 1 have significant effects on the distribution patterns of REEs in roots, some effects in stems and leaves, and almost no effects in grains. Accumulation rates of REEs in different organs follow the order of roots 〉 leaves 〉 stems 〉 panicle axes and crusts 〉 grains. The roots take up different REEs at almost the same rates, except for the selective accumulation of Th. In the aboveground parts, the accumulation rates of middle REEs (MREEs) and heavy REEs (HREEs) are higher than those of LREEs, there are significant selective accumulations of Eu and Tb. Accumulation rates of REEs in the roots, stems and leaves increase with the increasing applications of exogenous REEs, but they change slightly in the panicle axes, crusts and grains, demonstrating that it is easier for the roots, stems and leaves to accumulate exogenous REEs. Selective accumulation and fractionation of exoge nous Nd are also observed in rice organs including grains.展开更多
Three types of new high-efficiency phosphate fertilizers were made when pillared clays at certain proportions were added into ground phosphate rock. Chemical analyses showed that their soluble phosphorus content decre...Three types of new high-efficiency phosphate fertilizers were made when pillared clays at certain proportions were added into ground phosphate rock. Chemical analyses showed that their soluble phosphorus content decreased more than that of superphosphate. Pot experiment showed that, under equal weights, the new fertilizers increased their efficiency by a large margin over that of superphosphate. Researches on their structures by means of XRD, IR and EPR spectrum revealed that their crystal structures changed considerably, improving their activity and preventing the fixation of available phosphorus in the soil, and consequently, greatly improved the bioavailability and became the main cause of the increase of biomass.展开更多
A pot experiment combined with15N isotope techniques was conducted to evaluate effects of the varying rates of urea-N fertilizer application on yields,quality,and nitrogen use efficiency (NUE) of pakchoi cabbage (Bras...A pot experiment combined with15N isotope techniques was conducted to evaluate effects of the varying rates of urea-N fertilizer application on yields,quality,and nitrogen use efficiency (NUE) of pakchoi cabbage (Brassica chinensis L.) and asparagus lettuce (Lactuca saiva L.).15N-labbled urea (5.3515N atom %) was added to pots with 6.5 kg soil of 0.14,0.18,0.21,0.25,and 0.29 g N/kg soil,and applied in two splits:60 percent as basal dressing in the mixture and 40 percent as topdressing.The fresh yields of two vegetable species increased with the increasing input of urea-N,but there was a significant quadratic relationship between the dose of urea-N fertilizer application and the fresh yields.When the dosage of urea-N fertilizer reached a certain value,nitrate readily accumulated in the two kinds of plants due to the decrease in NR activity; furthermore,there was a linear negative correlation between nitrate content and NR activity.With the increasing input of urea-N,ascorbic acid and soluble sugar initially increased,declined after a while,and crude fiber rapidly decreased too.Total absorbed N (TAN),N derived from fertilizer (Ndff),and N derived from soil (Ndfs) increased,and the ratio of Ndff and TAN also increased,but the ratio of Ndfs and TAN as well as NUE of urea-N fertilizer decreased with the increasing input of urea-N.These results suggested that the increasing application of labeled N fertilizer led to the increase in unlabeled N (namely,Ndfs) presumably due to "added nitrogen interaction" (ANI),the decease in NUE of urea-N fertilizer may be due to excess fertilization beyond the levels of plant requirements and the ANI,and the decrease in the two vegetable yields with the increasing addition of urea-N possibly because the excess accumulation of nitrate reached a toxic level.展开更多
In this research, soil samples were frst polluted with 6 PAEs (i.e. DMP, DEP, DIBP, DBP, DEHP, and BBP) at 3 different concentration gradients (0, 10, and 20 mg/kg) and then treated with a highly-efficient degrada...In this research, soil samples were frst polluted with 6 PAEs (i.e. DMP, DEP, DIBP, DBP, DEHP, and BBP) at 3 different concentration gradients (0, 10, and 20 mg/kg) and then treated with a highly-efficient degradation fungus, Fusarium oxysporum (PO-Yi), to investigate the biodegradation of PAEs in pepper and eggplant soil. The findings revealed that PO-Yi can accelerate the degradation of PAEs in vegetable soils including pepper and eggplant soil to varying degrees. The highest absolute degradation rate (up to 39.5%) was observed in DEP-treated soils at the high pollution level (20 mg/kg), which was 14.2% higher than that at the middle pollution level (10 mg/kg). The degradation effect in the pepper soil was superior to that in the eggplant soil. Vegetable soil, either pepper soil or eggplant soil, which was polluted by various PAEs at different pollution gradients and then treated with PO-Yi fungus presented good bioremediation results. In the pepper and eggplant soil, 76.8% and 63.1% of the PAEs with a total volume of 60 mg/kg were degraded within 30 d respectively. PO-Yi, indigenous microorganisms, and the vegetables, i.e. pepper and eggplant had good synergistic effects on the degradation of compound PAEs in PAE-polluted pot soil.展开更多
Oil spills may considerably damage sensitive coastal wetlands. The phytoremediation potential and restoration of a dominant coastal marsh plant, Cyperus rotundus, for diesel pollutant and its phytoremediation effectiv...Oil spills may considerably damage sensitive coastal wetlands. The phytoremediation potential and restoration of a dominant coastal marsh plant, Cyperus rotundus, for diesel pollutant and its phytoremediation effectiveness were investigated in this open-air pot experiment. Cyperus rotundus was transplanted into soil contaminated with diesel at concentrations of 1 000, 5 000, 10 000, 15 000, 20 000 mg/kg. In order to better elucidate the biochemical and physiological responses to diesel pollutants, activity of the antioxidant enzymes peroxidase (POD), catalase (CAT) and ascorbic acid oxidase (AAO) were determined in the plant tissue after 50 d treatment at the levels mentioned above. The results showed that CAT and AAO of stem and leaf exhibited peak enzyme activities on 15 000 mg/kg soil and 10 000 mg/kg soil respectively, and declined at higher concentrations. Additionally, the increment of biomass and the content of soluble protein, as well as chlorophyll content were affected by diesel. The highest restoration effectiveness appeared at the level of 5 000 mg/kg. Collectively, Cyperus rotundus is a potential plant which can be used for restoring the diesel-contaminated soil.展开更多
In this research, soil samples were first polluted with 6 PAEs (i.e. DMP, DEP, DIBP, DBP, DEHP, and BBP) at 3 different concentration gradients (0, 10, and 20 mg/kg) and then treated with a highly-efficient degradatio...In this research, soil samples were first polluted with 6 PAEs (i.e. DMP, DEP, DIBP, DBP, DEHP, and BBP) at 3 different concentration gradients (0, 10, and 20 mg/kg) and then treated with a highly-efficient degradation fungus, Fusarium oxysporum (PO-Yi), to investigate the biodegradation of PAEs in pepper and eggplant soil. The findings revealed that PO-Yi can accelerate the degradation of PAEs in vegetable soils including pepper and eggplant soil to varying degrees. The highest absolute degradation rate (up to 39.5%) was observed in DEP-treated soils at the high pollution level (20 mg/kg), which was 14.2% higher than that at the middle pollution level (10 mg/kg). The degradation effect in the pepper soil was superior to that in the eggplant soil. Vegetable soil, either pepper soil or eggplant soil, which was polluted by various PAEs at different pollution gradients and then treated with PO-Yi fungus presented good bioremediation results. In the pepper and eggplant soil, 76.8% and 63.1% of the PAEs with a total volume of 60 mg/kg were degraded within 30 d respectively. PO-Yi, indigenous microorganisms, and the vegetables, i.e. pepper and eggplant had good synergistic effects on the degradation of compound PAEs in PAEpolluted pot soil.展开更多
In order to compare the differences in the accumulation of plumbum(Pb),cadmium(Cd),chromium(Cr),cuprum(Cu),nickel(Ni)and zinc(Zn)from the multi-contaminated,alkalescent soil in the plants of four-season big-leaf coria...In order to compare the differences in the accumulation of plumbum(Pb),cadmium(Cd),chromium(Cr),cuprum(Cu),nickel(Ni)and zinc(Zn)from the multi-contaminated,alkalescent soil in the plants of four-season big-leaf coriander,butter lettuce,four-season fast-growing pakchoi and four-season parsley to choose low accumulation vegetables,a pot experiment was conducted by using heavy metal salts to simulate high-,moderate-and low-level heavy metals multi-contaminated soils.The results showed that the multi-contaminated soil by high levels of Pb,Cd,Cr,Cu and Zn produced inhibition on biomass of four-season fast-growing pakchoi,failing to collect samples,but had no obvious inhibition on the growth of the three other vegetables.Among the four kinds of vegetables examined,the accumulation ability of four-season parsley to the five heavy metals of Pb,Cd,Cr,Cu and Zn was the strongest,while the accumulation ability of four-season fast-growing pakchoi to Ni was the strongest.In the high-level contaminated soil,the underground part of these four vegetables grown was more likely to accumulate heavy metals than their aboveground part.Both of vegetable varieties and heavy metal types can affect the accumulation of heavy metals in vegetables.Our research also found that four-season big-leaf coriander was high yielding and low accumulation of heavy metals.展开更多
[Objective] The paper was to isolate Colletotrichum sp.from strawberry and to screen effective fungicides.[Method] The indoor toxicity of 7 fungicides to Colletotrichum sp.was measured by growth rate method.The potted...[Objective] The paper was to isolate Colletotrichum sp.from strawberry and to screen effective fungicides.[Method] The indoor toxicity of 7 fungicides to Colletotrichum sp.was measured by growth rate method.The potted control effect of 3 fungicides on Colletotrichum sp.was evaluated.[Result] Fludioxonil exhibited the highest indoor toxicity to Colletotrichum sp.,with the EC50 value of 0.117 mg/L,and the EC50 value of prochloraz and difenoconazole were 0.141 and 0.357 mg/L,respectively.The pot experiment showed that the potted control effect of 20% fludioxonil2 000 times dilution on Colletotrichum sp.was the highest of 92.86%.450 g/L prochloraz EW 4 500 times dilution and 250 g/L difenoconazole EC2 500 times dilution also received high control effects against Colletotrichum sp.,which were 91.68% and 89.29%,respectively.[Conclusion] Fludioxonil,prochloraz and difenoconazole could be used for the control of strawberry anthracnose.展开更多
Organoarsenics are widely used as growth promoters in poultry industry,resulting in arsenic(As)accumulation in poultry litter.A greenhouse pot study was implemented to investigate the fate of arsenic originated from p...Organoarsenics are widely used as growth promoters in poultry industry,resulting in arsenic(As)accumulation in poultry litter.A greenhouse pot study was implemented to investigate the fate of arsenic originated from poultry litter and their effects on the growth of Brassica napus(oilseed rape),and assess their potential health risks.Five poultry litter application rates(0,5%,10%,20%and 40%)were used,dividing into two groups:one for soil incubation(SI)and the other for plant cultivation(PC).Experimental results indicated that the total arsenic for composted poultry litter was(10.94±0.23)mg/kg,As(V)and As(III)decreased while methylated arsenic increased after 21 d in SI and PC treatments.Seed germination rates were negatively correlated with monomethylarsenic acid(MMA,R2=0.63,p<0.05).The length and biomass of roots and shoots were significantly inhibited by poultry litter,but plant length of 5%treatments was slightly stimulated.Within an average weekly intake of 0.5 kg Brassica napuss,the risk quotient(RQ)values induced from roots nearly all surpassed the acceptable limit(1),were two orders magnitude higher than shoots.According to the potential risk to order,child exhibited the highest risk,adolescent ranked secondly,and adult exhibited the lowest risk.Hence,people should better avoid intake Brassica napus roots to reduce arsenic potential risk.展开更多
Aims Invasive species continue to be a worldwide threat to ecosystems mainly as a cause for biodiversity loss.Forest ecosystems,for example,are subject to a change in species composition due to the invasion of exotic ...Aims Invasive species continue to be a worldwide threat to ecosystems mainly as a cause for biodiversity loss.Forest ecosystems,for example,are subject to a change in species composition due to the invasion of exotic species.specifying the attributes that cause the strong competitiveness of several exotic species may improve the ability to understand and effectively manage plant invasions in the future.In this study the following hypotheses were tested:(1)biomass production of below-and aboveground plant compo-nents of the exotic tree species is higher than that of the natives,resulting in a higher competitiveness of the exotics;(2)the exclu-sion of root competition has a positive effect on the biomass pro-duction of the inferior native species;and(3)mixtures of native and exotic species yield a higher biomass production than the respective monocultures.Methods a pot experiment,containing about 2000 tree seedlings,was established.We investigated the biomass productivity and growth reactions of two native(Quercus robur l.,Carpinus betulus l.)and two exotic tree species(Prunus serotina Ehrh.,Robinia pseudoacacia l.)in different intra-and interspecific,competitive situations with and without the influence of root competition.Important Findingsthe biomass production of both exotic species was significantly higher and led to a strong competitive advantage,resulting in a biomass decrease of the less competitive native species.the high belowground biomass of both exotic species had a negative effect on the biomass production.the competitive pressure of exotic tree seedlings on the native ones was largely driven by root competition.Furthermore,mixtures of native and exotic tree species had a higher productivity than their growth in monocultures would have predicted.Competition was lower for exotic species in mixtures with the less productive native species compared to the competition in monocultures or in mixture with the other highly productive exotic species.accordingly,both highly competitive exotic species produced less biomass in mixture with each other compared to monocultures.Despite the significantly higher biomass of P.serotina in all mixtures and in monoculture,R.pseudoacacia seemed to be the dominating species.Due to its strong root competition,R.pseudoacacia significantly reduced the biomass production of P.serotina.展开更多
基金Project supported by the National Natural Science Foundation of China (No. 30270800).
文摘The feasibility of steel slag used as an iron fertilizer was studied in a pot experiment with corn. Slag alone or acidified slag was added to two Fe-deficient calcareous soils at different rates. Results showed that moderate rates (10 and 20 g kg-1) of slag or acidified slag substantially increased corn dry matter yield and Fe uptake. Application of steel slag increased the residual concentration of ammonium bicarbonate-diethylenetriamine pentaacetic acid (AB-DTPA) extractable Fe in the soils. The increase of extractable Fe was usually proportional to the application rate, and enhanced by the acidification of slag. Steel slag appeared to be a promising and inexpensive source of Fe to alleviate crop Fe chlorosis in Fe-deficient calcareous soils.
文摘Water is the source of life. China ranks No.13 among the water shortage countries. The most of the water is utilized in agriculture, while the utilization rate of irrigation water is only 40%, so it is very important to study on the theory and technology on high efficient water utilization. The purpose for this study is to find out the optimal drainage line on potted flowers through the analysis of experimental results of Aglaonema modestum and Rhododendron simsii Planch in different drainage lines.
基金Supported by National Department Public Benefit Research Foundation(201203013)Modern Agricultural Industry Technology System(CARS-11-B-15)+2 种基金IPNI Project(JIANGSU-10)Special Fund for Agro-scientific Research in the Public Interest(201003014-1-2)Jiangsu Agriculture S&T Self-Innovation Project[CX(12)3037]~~
文摘[Objective] The aim was to explore release characteristics of vinyl chlo- ride-vinyl acetate copolymer controlled-release N fertilizer and the effects on minerat nitrogen in soils. [Method] Vinyl chloride-vinyl acetate copolymer and hydroxyl-modi- fied VCNAc were taken as coating materials to prepare slow release fertilizer. Nutri- ent release characteristics of VC/VAc slow release fertilizer was evaluated by water immersion method and the effects of VC/VAc slow release fertilizer on mineral ni- trogen were researched by pot experiment. [Result] The release periods of VC-VAc controlled-release urea and hydroxyl-modified VC/VAc coated urea were 60 and 50 d, respectively. Furthermore, the content of ammonium nitrogen reached the peak on the 30th d and the content of nitrate nitrogen reached the peak on the 60th d in soils in treatments with VCNAc and hydroxyl-modified VC/VAc; the content of nitrate nitrogen rose again on the 120th d in the treatment with VC/VAc. In terms of wheat yield, different treatments showed insignificant differences and rice yield in the treatment with VCNAc was significantly higher than that in the treatment with hy- droxyl-modified VCNAc (P〈0.05). [Conclusion] The release days of slow controlled- release fertilizer vary upon pot experiment method and water immersion method. Slow controlled-release fertilizer is not suitable for monoculture, due to long fertilizer efficiency, but multiple cropping would be optimal for its role to be fully exploited.
基金The National Natural Science Foundation of China (No. 20007002)the Innovation Project of the Chinese Academy of Sciences (No.KSCX2-SW-128)the Science and Technology Commission Fund of Shanghai City, China (No. 02DZ1201)
文摘In order to better understand land application of sewage sludge, the characterization of heavy metals and organic pollutants were investigated in three different sewage sludges in Shanghai City, China. It was found that the total concentrations of Cd in all of sewage sludge and total concentrations of Zn in Jinshan sewage sludge, as well as those ofZn, Cu, and Ni in Taopu sludge are higher than Chinese regulation limit of pollutants for sludge to be used in agriculture. Leachability of rig in all of studied samples and that of Cd in Taopu sewage sludge exceed the limit values of waste solid extraction standard in China legislation. Based on the characteristics for three kinds of sewage sludge, a pot experiment was conducted to investigate the effect of soil amended with Quyang sewage sludge on the accumulation of heavy metalo.by Begonia semperfloreas-hybr; Ophiopogon japonicas (L.F.) Ker-Gaw; Loropetalum chindense-var, rubrum; Dendranthema morifolium; Viola tricolor; A ntirrhinum majas; Buxas radicans Sieb; Viburnum macrocephalum; Osmanthas fragrans Lour; Cinnamomum camphora siebold and Ligustrum lucidum ait. Results showed that 8 species of plant survived in the amended soil, and moreover they flourished as well as those cultivated in the control soil. The heavy metal concentration in plants varied with species, As, Pb, Cd and Cr concentration being the highest in the four herbaceous species studied, particularly in the roots of D. morifolium. These plants, however, did not show accumulator of As, Pb, Cd and Cr. The highest concentration of Ni and Hg was found in the roots ofD. morifolium, followed by the leaves ofB. semperflorens-hybr. Levels of Zn and Cu were much higher in D. morifolium than in the other plant species. D. morifolium accumulated Ni, Hg, Cu and Zn, which may contribute to the decrease of heavy metal contents in the amended soil. Treatment with sewage sludge did not significantly affect the uptake of heavy metals by the L. chindense-var, rubrum, however, it significantly affected the uptake of heavy metals by D. morifolium.
文摘Accumulation and fractionation of rare earth elements (REEs) were studied through applications of exogenous REEs in soils with pot-cultured rice for 2 years. The results show that the biomass of rice consistently decreases at sprouting and maturity stages when the amount of exogenous REEs are over 400 mg· kg^- 1. It illustrates that the endurance of rice to exogenous REE exposure is much weaker than that of wheat. The distribution patterns of REEs in rice of the control are similar to that in the soil, both exhibiting light REE (LREE) enrichment and positive Tb in the roots and the aboveground parts. Applications of exogenous REEs ranging from 400 to 1200 mg· kg^- 1 have significant effects on the distribution patterns of REEs in roots, some effects in stems and leaves, and almost no effects in grains. Accumulation rates of REEs in different organs follow the order of roots 〉 leaves 〉 stems 〉 panicle axes and crusts 〉 grains. The roots take up different REEs at almost the same rates, except for the selective accumulation of Th. In the aboveground parts, the accumulation rates of middle REEs (MREEs) and heavy REEs (HREEs) are higher than those of LREEs, there are significant selective accumulations of Eu and Tb. Accumulation rates of REEs in the roots, stems and leaves increase with the increasing applications of exogenous REEs, but they change slightly in the panicle axes, crusts and grains, demonstrating that it is easier for the roots, stems and leaves to accumulate exogenous REEs. Selective accumulation and fractionation of exoge nous Nd are also observed in rice organs including grains.
基金Project supported by the National Science Foundation of China (No.40202007) and the Provincial National Science Foundation ofGuangdong, China (Nos. 000623, 020938, 04020017)
文摘Three types of new high-efficiency phosphate fertilizers were made when pillared clays at certain proportions were added into ground phosphate rock. Chemical analyses showed that their soluble phosphorus content decreased more than that of superphosphate. Pot experiment showed that, under equal weights, the new fertilizers increased their efficiency by a large margin over that of superphosphate. Researches on their structures by means of XRD, IR and EPR spectrum revealed that their crystal structures changed considerably, improving their activity and preventing the fixation of available phosphorus in the soil, and consequently, greatly improved the bioavailability and became the main cause of the increase of biomass.
基金Supported by International Plant Nutrition Institute (IPNI China Program: Hunan-11 )Hunan Provincial Key Subject ( Grant No.04NK2006)
文摘A pot experiment combined with15N isotope techniques was conducted to evaluate effects of the varying rates of urea-N fertilizer application on yields,quality,and nitrogen use efficiency (NUE) of pakchoi cabbage (Brassica chinensis L.) and asparagus lettuce (Lactuca saiva L.).15N-labbled urea (5.3515N atom %) was added to pots with 6.5 kg soil of 0.14,0.18,0.21,0.25,and 0.29 g N/kg soil,and applied in two splits:60 percent as basal dressing in the mixture and 40 percent as topdressing.The fresh yields of two vegetable species increased with the increasing input of urea-N,but there was a significant quadratic relationship between the dose of urea-N fertilizer application and the fresh yields.When the dosage of urea-N fertilizer reached a certain value,nitrate readily accumulated in the two kinds of plants due to the decrease in NR activity; furthermore,there was a linear negative correlation between nitrate content and NR activity.With the increasing input of urea-N,ascorbic acid and soluble sugar initially increased,declined after a while,and crude fiber rapidly decreased too.Total absorbed N (TAN),N derived from fertilizer (Ndff),and N derived from soil (Ndfs) increased,and the ratio of Ndff and TAN also increased,but the ratio of Ndfs and TAN as well as NUE of urea-N fertilizer decreased with the increasing input of urea-N.These results suggested that the increasing application of labeled N fertilizer led to the increase in unlabeled N (namely,Ndfs) presumably due to "added nitrogen interaction" (ANI),the decease in NUE of urea-N fertilizer may be due to excess fertilization beyond the levels of plant requirements and the ANI,and the decrease in the two vegetable yields with the increasing addition of urea-N possibly because the excess accumulation of nitrate reached a toxic level.
基金Supported by Hunan Key Research&Development Project(2016SK2053)Innovation Fund Project of Hunan Agricultural Science(2017JC65,2018ZD04)+1 种基金Project of International Joint Lab on Fruits&Vegetables Processing,Quality and Safety(2017)Project of Hunan Key Lab of Fruits&Vegetables Storage,Processing,Quality and Safety(2018)~~
文摘In this research, soil samples were frst polluted with 6 PAEs (i.e. DMP, DEP, DIBP, DBP, DEHP, and BBP) at 3 different concentration gradients (0, 10, and 20 mg/kg) and then treated with a highly-efficient degradation fungus, Fusarium oxysporum (PO-Yi), to investigate the biodegradation of PAEs in pepper and eggplant soil. The findings revealed that PO-Yi can accelerate the degradation of PAEs in vegetable soils including pepper and eggplant soil to varying degrees. The highest absolute degradation rate (up to 39.5%) was observed in DEP-treated soils at the high pollution level (20 mg/kg), which was 14.2% higher than that at the middle pollution level (10 mg/kg). The degradation effect in the pepper soil was superior to that in the eggplant soil. Vegetable soil, either pepper soil or eggplant soil, which was polluted by various PAEs at different pollution gradients and then treated with PO-Yi fungus presented good bioremediation results. In the pepper and eggplant soil, 76.8% and 63.1% of the PAEs with a total volume of 60 mg/kg were degraded within 30 d respectively. PO-Yi, indigenous microorganisms, and the vegetables, i.e. pepper and eggplant had good synergistic effects on the degradation of compound PAEs in PAE-polluted pot soil.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.40973073, 41073072)the Shanghai Leading Academic Discipline Project (Grant No.S30109),and the Technology Foundation of Shanghai University
文摘Oil spills may considerably damage sensitive coastal wetlands. The phytoremediation potential and restoration of a dominant coastal marsh plant, Cyperus rotundus, for diesel pollutant and its phytoremediation effectiveness were investigated in this open-air pot experiment. Cyperus rotundus was transplanted into soil contaminated with diesel at concentrations of 1 000, 5 000, 10 000, 15 000, 20 000 mg/kg. In order to better elucidate the biochemical and physiological responses to diesel pollutants, activity of the antioxidant enzymes peroxidase (POD), catalase (CAT) and ascorbic acid oxidase (AAO) were determined in the plant tissue after 50 d treatment at the levels mentioned above. The results showed that CAT and AAO of stem and leaf exhibited peak enzyme activities on 15 000 mg/kg soil and 10 000 mg/kg soil respectively, and declined at higher concentrations. Additionally, the increment of biomass and the content of soluble protein, as well as chlorophyll content were affected by diesel. The highest restoration effectiveness appeared at the level of 5 000 mg/kg. Collectively, Cyperus rotundus is a potential plant which can be used for restoring the diesel-contaminated soil.
文摘In this research, soil samples were first polluted with 6 PAEs (i.e. DMP, DEP, DIBP, DBP, DEHP, and BBP) at 3 different concentration gradients (0, 10, and 20 mg/kg) and then treated with a highly-efficient degradation fungus, Fusarium oxysporum (PO-Yi), to investigate the biodegradation of PAEs in pepper and eggplant soil. The findings revealed that PO-Yi can accelerate the degradation of PAEs in vegetable soils including pepper and eggplant soil to varying degrees. The highest absolute degradation rate (up to 39.5%) was observed in DEP-treated soils at the high pollution level (20 mg/kg), which was 14.2% higher than that at the middle pollution level (10 mg/kg). The degradation effect in the pepper soil was superior to that in the eggplant soil. Vegetable soil, either pepper soil or eggplant soil, which was polluted by various PAEs at different pollution gradients and then treated with PO-Yi fungus presented good bioremediation results. In the pepper and eggplant soil, 76.8% and 63.1% of the PAEs with a total volume of 60 mg/kg were degraded within 30 d respectively. PO-Yi, indigenous microorganisms, and the vegetables, i.e. pepper and eggplant had good synergistic effects on the degradation of compound PAEs in PAEpolluted pot soil.
文摘In order to compare the differences in the accumulation of plumbum(Pb),cadmium(Cd),chromium(Cr),cuprum(Cu),nickel(Ni)and zinc(Zn)from the multi-contaminated,alkalescent soil in the plants of four-season big-leaf coriander,butter lettuce,four-season fast-growing pakchoi and four-season parsley to choose low accumulation vegetables,a pot experiment was conducted by using heavy metal salts to simulate high-,moderate-and low-level heavy metals multi-contaminated soils.The results showed that the multi-contaminated soil by high levels of Pb,Cd,Cr,Cu and Zn produced inhibition on biomass of four-season fast-growing pakchoi,failing to collect samples,but had no obvious inhibition on the growth of the three other vegetables.Among the four kinds of vegetables examined,the accumulation ability of four-season parsley to the five heavy metals of Pb,Cd,Cr,Cu and Zn was the strongest,while the accumulation ability of four-season fast-growing pakchoi to Ni was the strongest.In the high-level contaminated soil,the underground part of these four vegetables grown was more likely to accumulate heavy metals than their aboveground part.Both of vegetable varieties and heavy metal types can affect the accumulation of heavy metals in vegetables.Our research also found that four-season big-leaf coriander was high yielding and low accumulation of heavy metals.
基金Supported by Overseas Talents Introduction Project of Shandong Academy of Agricultural Sciences(CXGC2021B04)。
文摘[Objective] The paper was to isolate Colletotrichum sp.from strawberry and to screen effective fungicides.[Method] The indoor toxicity of 7 fungicides to Colletotrichum sp.was measured by growth rate method.The potted control effect of 3 fungicides on Colletotrichum sp.was evaluated.[Result] Fludioxonil exhibited the highest indoor toxicity to Colletotrichum sp.,with the EC50 value of 0.117 mg/L,and the EC50 value of prochloraz and difenoconazole were 0.141 and 0.357 mg/L,respectively.The pot experiment showed that the potted control effect of 20% fludioxonil2 000 times dilution on Colletotrichum sp.was the highest of 92.86%.450 g/L prochloraz EW 4 500 times dilution and 250 g/L difenoconazole EC2 500 times dilution also received high control effects against Colletotrichum sp.,which were 91.68% and 89.29%,respectively.[Conclusion] Fludioxonil,prochloraz and difenoconazole could be used for the control of strawberry anthracnose.
基金National Natural Science Foundation of China(No.21177087)the National High Technology Research and Development Program of China(2012AA101405).
文摘Organoarsenics are widely used as growth promoters in poultry industry,resulting in arsenic(As)accumulation in poultry litter.A greenhouse pot study was implemented to investigate the fate of arsenic originated from poultry litter and their effects on the growth of Brassica napus(oilseed rape),and assess their potential health risks.Five poultry litter application rates(0,5%,10%,20%and 40%)were used,dividing into two groups:one for soil incubation(SI)and the other for plant cultivation(PC).Experimental results indicated that the total arsenic for composted poultry litter was(10.94±0.23)mg/kg,As(V)and As(III)decreased while methylated arsenic increased after 21 d in SI and PC treatments.Seed germination rates were negatively correlated with monomethylarsenic acid(MMA,R2=0.63,p<0.05).The length and biomass of roots and shoots were significantly inhibited by poultry litter,but plant length of 5%treatments was slightly stimulated.Within an average weekly intake of 0.5 kg Brassica napuss,the risk quotient(RQ)values induced from roots nearly all surpassed the acceptable limit(1),were two orders magnitude higher than shoots.According to the potential risk to order,child exhibited the highest risk,adolescent ranked secondly,and adult exhibited the lowest risk.Hence,people should better avoid intake Brassica napus roots to reduce arsenic potential risk.
文摘Aims Invasive species continue to be a worldwide threat to ecosystems mainly as a cause for biodiversity loss.Forest ecosystems,for example,are subject to a change in species composition due to the invasion of exotic species.specifying the attributes that cause the strong competitiveness of several exotic species may improve the ability to understand and effectively manage plant invasions in the future.In this study the following hypotheses were tested:(1)biomass production of below-and aboveground plant compo-nents of the exotic tree species is higher than that of the natives,resulting in a higher competitiveness of the exotics;(2)the exclu-sion of root competition has a positive effect on the biomass pro-duction of the inferior native species;and(3)mixtures of native and exotic species yield a higher biomass production than the respective monocultures.Methods a pot experiment,containing about 2000 tree seedlings,was established.We investigated the biomass productivity and growth reactions of two native(Quercus robur l.,Carpinus betulus l.)and two exotic tree species(Prunus serotina Ehrh.,Robinia pseudoacacia l.)in different intra-and interspecific,competitive situations with and without the influence of root competition.Important Findingsthe biomass production of both exotic species was significantly higher and led to a strong competitive advantage,resulting in a biomass decrease of the less competitive native species.the high belowground biomass of both exotic species had a negative effect on the biomass production.the competitive pressure of exotic tree seedlings on the native ones was largely driven by root competition.Furthermore,mixtures of native and exotic tree species had a higher productivity than their growth in monocultures would have predicted.Competition was lower for exotic species in mixtures with the less productive native species compared to the competition in monocultures or in mixture with the other highly productive exotic species.accordingly,both highly competitive exotic species produced less biomass in mixture with each other compared to monocultures.Despite the significantly higher biomass of P.serotina in all mixtures and in monoculture,R.pseudoacacia seemed to be the dominating species.Due to its strong root competition,R.pseudoacacia significantly reduced the biomass production of P.serotina.