Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly...Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. On the other hand, this sludge has benefit for plants and soils. Sludge samples were collected over a 12 month period from sewage treatment plants （STP＇s）, i.e, Khairathabad and Meeralam Tank, Hyderabad, India and analyzed for C, H, N, S by elementar analyzer, P, K, Ca, Mg by spectrophotometer and heavy metals like Zn, Pb, Ni, Cu, Cd by atomic absorption spectrophotometer. The sludge contained approximately 50% organic matter and 1-4% inorganic carbon. Organic and inorganic carbon, organic nitrogen, inorganic phosphorous, Ca and Mg were found to be present in sludge at a relatively constant concentration with respect to sampling time. Inorganic N, organic P, K, and all metals were found to be quite variable with time when sludge produced from different STP＇s.展开更多
At present, there is little commercial sale of biochar, since farmers find they can not gain a return on their investment in this amendment in the first few years after its application, because of the high cost associ...At present, there is little commercial sale of biochar, since farmers find they can not gain a return on their investment in this amendment in the first few years after its application, because of the high cost associated with large application rates. To overcome this constraint, development of artificially aged enriched biochar-mineral complexes(BMCs), having a higher mineral content, surface functionality, exchangeable cations, high concentration of magnetic iron(Fe) nanoparticles, and higher water-extractable organic compounds has been undertaken by a combined team of researchers and a commercial company. Two biochars produced under different pyrolysis conditions were activated with a phosphoric acid treatment. A mixture of clay, chicken litter, and minerals were added to the biochar, and then this composite was torrefied at either 180 or 220?C. In this study a pot experiment was carried out in glasshouse conditions to determine the effects of four different BMCs, with different formulations applied at rates of 100 and 200 kg ha-1, on the mycorrhizal colonisation, wheat growth and nutrient uptake, and soil quality improvement. It was found that the phosphorus(P) and nitrogen uptake in wheat shoots were significantly greater for a low application rate of BMCs(100 kg ha-1). The present formulation of BMC was effective in enhancing growth of wheat at low application rate(100 kg ha-1). The increase in growth appeared due to an increase in P uptake in the plants that could be partly attributed to an increase in mycorrhizal colonisation and partly due to the properties of the BMC.展开更多
We studied the uptake of ammonium, nitrate, and a variety of amino acids by alpine plant species in the Kobresia humil alpine meadow ecosystem in situ. We examined the extent of niche separation in uptake of N source ...We studied the uptake of ammonium, nitrate, and a variety of amino acids by alpine plant species in the Kobresia humil alpine meadow ecosystem in situ. We examined the extent of niche separation in uptake of N source by different plant species in alpine communities, and investigated the contribution of symbiotically fixed N to the total N in alpine meadow. The results are （1） δ15N natural abundance values of 13 plant species lie between -2.680‰ and 5.169‰, and the scope is 7.849‰. （2） Le- guminous plants, such as Trigonella ruthenica, Gueldenstaedtia diversiffolia, and Oxytyopis ochrocephala, and non-legumi- nous plant Gentiana straminea uptake low amounts of 15N labeled ammonium, nitrate, glycine or aspartate in soil. （3） As far as the plant uptake of organic N is concerned, Kobresia humilis, Poa pratensis, and Gentiuna spathutifolta can effectively uptake organic nitrogen, and about 37%-40% of the nitrogen of these species comes from soil organic nitrogen sources （such as glycine and aspartate）. Stipa aliena can effectively uptake nitrate, and 60% of its nitrogen comes from soil nitrate. Potentilla anserina, Poa pratensis, and Thalictrum alpinum can effectively absorb ammonium in comparason to other plant species in the meadow, and about 25%-27% of the nitrogen in these plants comes from soil ammonium. （4） The contribution of leguminous fixed N to total N is 7.48%-9.26% in Kobresia humilis alpine meadow. （5） These data show many plant species of alpine meadow may effectively utilize dissolved organic nitrogen such as amino acids, and these plants have diverse ways to uptake soil nitrogen in alpine meadows. Based on the results we can partly explain why there are abundant biodiversities and how plants at alpine habitat utilize the limited soil N sources.展开更多
The positive effects of silicon(Si) on growth of plants have been well documented;however,the impact of Si on plant nutrient uptake remains unclear.The growth,nutrient content and uptake of wheat(Triticum aestivum L.)...The positive effects of silicon(Si) on growth of plants have been well documented;however,the impact of Si on plant nutrient uptake remains unclear.The growth,nutrient content and uptake of wheat(Triticum aestivum L.),canola(Brassica napus L.) and cotton(Gossypium hirsutum L.) plants were evaluated with or without application of 1.5 mmol L^(-1) Si.Application of Si increased dry weights by 8%,30%and 30%and relative growth rate(RGR) by 10%,13%and 17%in the cotton,canola and wheat plants,respectively.The plant relative water content(RWC) was also increased,but the plant transpiration was decreased by Si application.The uptake and content of Ca^(2+) were 19%and 21%lower in the cotton and wheat plants with Si than those without Si,respectively;however,Si application increased both K^+ and Fe uptake and contents in all plant species.Silicon application reduced B uptake and content only in cotton and increased P and Zn^(2+) contents in all three plant species.The decrease in Ca^(2+) uptake by Si application was sustained even in the presence of metabolic inhibitors 2,4-dinitrophenol and sodium cyanide.Uptake of Ca^(2+) by Si application was enhanced or did not change when plant shoots were saturated with water vapor or their roots were exposed to low temperature.Thus,Si application increased the uptake of transcellularly transported elements like K^+,P,Zn^(2+) and Fe.In contrast,Ca2+ uptake which occurred via both apoplastic and transcellular pathways was decreased by Si application,possibly through reduction of apoplastic uptake.More efficient nutrient uptake might be another promoting effect of Si on plant growth.展开更多
We studied the effects of hardwood-derived biochar（BC） and the phytohormone-producing endophyte Galactomyces geotrichum WLL1 in soybean（Glycine max（L.） Merr.） with respect to basic, macro- and micronutrient upta...We studied the effects of hardwood-derived biochar（BC） and the phytohormone-producing endophyte Galactomyces geotrichum WLL1 in soybean（Glycine max（L.） Merr.） with respect to basic, macro- and micronutrient uptakes and assimilations, and their subsequent effects on the regulation of functional amino acids, isoflavones, fatty acid composition, total sugar contents, total phenolic contents, and 1,1-diphenyl-2-picrylhydrazyl（DPPH）-scavenging activity. The assimilation of basic nutrients such as nitrogen was up-regulated, leaving carbon, oxygen, and hydrogen unaffected in BC＋G. geotrichum-treated soybean plants. In comparison, the uptakes of macro- and micronutrients fluctuated in the individual or co-application of BC and G. geotrichum in soybean plant organs and rhizospheric substrate. Moreover, the same attribute was recorded for the regulation of functional amino acids, isoflavones, fatty acid composition, total sugar contents, total phenolic contents, and DPPH-scavenging activity. Collectively, these results showed that BC＋G. geotrichum-treated soybean yielded better results than did the plants treated with individual applications. It was concluded that BC is an additional nutriment source and that the G. geotrichum acts as a plant biostimulating source and the effects of both are additive towards plant growth promotion. Strategies involving the incorporation of BC and endophytic symbiosis may help achieve eco-friendly agricultural production, thus reducing the excessive use of chemical agents.展开更多
In situ evaluating the availability of soil nutrients has been a challenge. In this study, a new type of Device for Simulating Soil Nutrient Extraction and Plant Uptake （DSSNEPU） and its operating procedures were in...In situ evaluating the availability of soil nutrients has been a challenge. In this study, a new type of Device for Simulating Soil Nutrient Extraction and Plant Uptake （DSSNEPU） and its operating procedures were introduced. The device consists of a sampling tube, a fluid supply system, a low pressure system, a tube sheath and an elution cylinder. The sampling tube was firstly soaked in the solution of 0.5 mol L-1 NaHCO3 and then buried into soils. The fluid supply system was connected to the sampling tube and the deionized water was supplied. During the period, low pressure system started a vacuum for 3 min every 10 rain interval. After extraction, the sampling tube was removed and the nutrients on the sampling tube were eluted with 0.5 tool L-1 HCl. The elution solution was used for nutrient measurement. The amounts of P and K extracted by DSSNEPU reached the maximal values after 4 h. No significant increases of P and K were observed for longer extraction duration. The optimal temperature for extracting P and K was 30 ℃ in this experiment. Extracted P and K were increased by 83.3% and 84.6% with the employment of low pressure system in comparison to those without employing low pressure system. Correlation analysis indicated that 1~ and K extracted by DSSNEPU were highly correlated with those by conventional chemical extraction and by plant uptake. The above results suggest that this device is applicable to assess the availability of nutrients in soils.展开更多
文摘Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. On the other hand, this sludge has benefit for plants and soils. Sludge samples were collected over a 12 month period from sewage treatment plants （STP＇s）, i.e, Khairathabad and Meeralam Tank, Hyderabad, India and analyzed for C, H, N, S by elementar analyzer, P, K, Ca, Mg by spectrophotometer and heavy metals like Zn, Pb, Ni, Cu, Cd by atomic absorption spectrophotometer. The sludge contained approximately 50% organic matter and 1-4% inorganic carbon. Organic and inorganic carbon, organic nitrogen, inorganic phosphorous, Ca and Mg were found to be present in sludge at a relatively constant concentration with respect to sampling time. Inorganic N, organic P, K, and all metals were found to be quite variable with time when sludge produced from different STP＇s.
基金supported by Ven Earth LLC,San Francisco,CA,USA and the Australian Research Council
文摘At present, there is little commercial sale of biochar, since farmers find they can not gain a return on their investment in this amendment in the first few years after its application, because of the high cost associated with large application rates. To overcome this constraint, development of artificially aged enriched biochar-mineral complexes(BMCs), having a higher mineral content, surface functionality, exchangeable cations, high concentration of magnetic iron(Fe) nanoparticles, and higher water-extractable organic compounds has been undertaken by a combined team of researchers and a commercial company. Two biochars produced under different pyrolysis conditions were activated with a phosphoric acid treatment. A mixture of clay, chicken litter, and minerals were added to the biochar, and then this composite was torrefied at either 180 or 220?C. In this study a pot experiment was carried out in glasshouse conditions to determine the effects of four different BMCs, with different formulations applied at rates of 100 and 200 kg ha-1, on the mycorrhizal colonisation, wheat growth and nutrient uptake, and soil quality improvement. It was found that the phosphorus(P) and nitrogen uptake in wheat shoots were significantly greater for a low application rate of BMCs(100 kg ha-1). The present formulation of BMC was effective in enhancing growth of wheat at low application rate(100 kg ha-1). The increase in growth appeared due to an increase in P uptake in the plants that could be partly attributed to an increase in mycorrhizal colonisation and partly due to the properties of the BMC.
基金supported by National Natural Science Foundation of China(Grant Nos.30660120 and 41030105)National Basic Research Program of China (Grant No. 2009CB421102)International Cooperation Program of Science and Technology Department of Qinghai Province (Grant No. 2010-H-809)
文摘We studied the uptake of ammonium, nitrate, and a variety of amino acids by alpine plant species in the Kobresia humil alpine meadow ecosystem in situ. We examined the extent of niche separation in uptake of N source by different plant species in alpine communities, and investigated the contribution of symbiotically fixed N to the total N in alpine meadow. The results are （1） δ15N natural abundance values of 13 plant species lie between -2.680‰ and 5.169‰, and the scope is 7.849‰. （2） Le- guminous plants, such as Trigonella ruthenica, Gueldenstaedtia diversiffolia, and Oxytyopis ochrocephala, and non-legumi- nous plant Gentiana straminea uptake low amounts of 15N labeled ammonium, nitrate, glycine or aspartate in soil. （3） As far as the plant uptake of organic N is concerned, Kobresia humilis, Poa pratensis, and Gentiuna spathutifolta can effectively uptake organic nitrogen, and about 37%-40% of the nitrogen of these species comes from soil organic nitrogen sources （such as glycine and aspartate）. Stipa aliena can effectively uptake nitrate, and 60% of its nitrogen comes from soil nitrate. Potentilla anserina, Poa pratensis, and Thalictrum alpinum can effectively absorb ammonium in comparason to other plant species in the meadow, and about 25%-27% of the nitrogen in these plants comes from soil ammonium. （4） The contribution of leguminous fixed N to total N is 7.48%-9.26% in Kobresia humilis alpine meadow. （5） These data show many plant species of alpine meadow may effectively utilize dissolved organic nitrogen such as amino acids, and these plants have diverse ways to uptake soil nitrogen in alpine meadows. Based on the results we can partly explain why there are abundant biodiversities and how plants at alpine habitat utilize the limited soil N sources.
基金Golestan University Deputy of Research and Office of Higher Education,Iran,for financial support to Pooyan Mehrabanjoubani in the form of grants for Ph.D.research projects
文摘The positive effects of silicon(Si) on growth of plants have been well documented;however,the impact of Si on plant nutrient uptake remains unclear.The growth,nutrient content and uptake of wheat(Triticum aestivum L.),canola(Brassica napus L.) and cotton(Gossypium hirsutum L.) plants were evaluated with or without application of 1.5 mmol L^(-1) Si.Application of Si increased dry weights by 8%,30%and 30%and relative growth rate(RGR) by 10%,13%and 17%in the cotton,canola and wheat plants,respectively.The plant relative water content(RWC) was also increased,but the plant transpiration was decreased by Si application.The uptake and content of Ca^(2+) were 19%and 21%lower in the cotton and wheat plants with Si than those without Si,respectively;however,Si application increased both K^+ and Fe uptake and contents in all plant species.Silicon application reduced B uptake and content only in cotton and increased P and Zn^(2+) contents in all three plant species.The decrease in Ca^(2+) uptake by Si application was sustained even in the presence of metabolic inhibitors 2,4-dinitrophenol and sodium cyanide.Uptake of Ca^(2+) by Si application was enhanced or did not change when plant shoots were saturated with water vapor or their roots were exposed to low temperature.Thus,Si application increased the uptake of transcellularly transported elements like K^+,P,Zn^(2+) and Fe.In contrast,Ca2+ uptake which occurred via both apoplastic and transcellular pathways was decreased by Si application,possibly through reduction of apoplastic uptake.More efficient nutrient uptake might be another promoting effect of Si on plant growth.
基金Project supported by the Korea Institute of Planning and Evaluation for Technology in Food,Agriculture,Forestry and Fisheries(IPET) through Agriculture,Food and Rural Affairs Research Center Support Program,funded by Ministry of Agriculture,Food and Rural Affairs(MAFRA)(716001-7)
文摘We studied the effects of hardwood-derived biochar（BC） and the phytohormone-producing endophyte Galactomyces geotrichum WLL1 in soybean（Glycine max（L.） Merr.） with respect to basic, macro- and micronutrient uptakes and assimilations, and their subsequent effects on the regulation of functional amino acids, isoflavones, fatty acid composition, total sugar contents, total phenolic contents, and 1,1-diphenyl-2-picrylhydrazyl（DPPH）-scavenging activity. The assimilation of basic nutrients such as nitrogen was up-regulated, leaving carbon, oxygen, and hydrogen unaffected in BC＋G. geotrichum-treated soybean plants. In comparison, the uptakes of macro- and micronutrients fluctuated in the individual or co-application of BC and G. geotrichum in soybean plant organs and rhizospheric substrate. Moreover, the same attribute was recorded for the regulation of functional amino acids, isoflavones, fatty acid composition, total sugar contents, total phenolic contents, and DPPH-scavenging activity. Collectively, these results showed that BC＋G. geotrichum-treated soybean yielded better results than did the plants treated with individual applications. It was concluded that BC is an additional nutriment source and that the G. geotrichum acts as a plant biostimulating source and the effects of both are additive towards plant growth promotion. Strategies involving the incorporation of BC and endophytic symbiosis may help achieve eco-friendly agricultural production, thus reducing the excessive use of chemical agents.
基金Supported by the National Natural Science Foundation of China (Nos. 31071847 and 31172026)the National Basic Research Program (973 Program) of China (No. 2007CB109303)+2 种基金the Ph.D. Programs Foundation of Ministry of Education of China (No. 20104404110016)the Foundation for High-Level Talents in Higher Education of Guangdong, Chinathe Preferred Foundation for Returned Scholars, Ministry of Personnel of China (No. 2010412)
文摘In situ evaluating the availability of soil nutrients has been a challenge. In this study, a new type of Device for Simulating Soil Nutrient Extraction and Plant Uptake （DSSNEPU） and its operating procedures were introduced. The device consists of a sampling tube, a fluid supply system, a low pressure system, a tube sheath and an elution cylinder. The sampling tube was firstly soaked in the solution of 0.5 mol L-1 NaHCO3 and then buried into soils. The fluid supply system was connected to the sampling tube and the deionized water was supplied. During the period, low pressure system started a vacuum for 3 min every 10 rain interval. After extraction, the sampling tube was removed and the nutrients on the sampling tube were eluted with 0.5 tool L-1 HCl. The elution solution was used for nutrient measurement. The amounts of P and K extracted by DSSNEPU reached the maximal values after 4 h. No significant increases of P and K were observed for longer extraction duration. The optimal temperature for extracting P and K was 30 ℃ in this experiment. Extracted P and K were increased by 83.3% and 84.6% with the employment of low pressure system in comparison to those without employing low pressure system. Correlation analysis indicated that 1~ and K extracted by DSSNEPU were highly correlated with those by conventional chemical extraction and by plant uptake. The above results suggest that this device is applicable to assess the availability of nutrients in soils.
