The study was conducted to reveal P fractions and N forms changing characters during composting of pig manure with rice straw.During composting,the NH 4 ＋-N concentration decreased and reached at a relatively low va...The study was conducted to reveal P fractions and N forms changing characters during composting of pig manure with rice straw.During composting,the NH 4 ＋-N concentration decreased and reached at a relatively low value（〈400 mg kg-1） in the final compost,while the NO 3--N concentration increased.Total N losses mainly occurred during thermophilic phase due to the high temperature,the high NH 4 ＋-N concentration and the increase of pH value.Labile inorganic P was dominated in the pig manure and initial compost mixture.During composting,the proportion of labile inorganic P of total extracted P decreased,while the proportion of Fe＋Al-bound P,Ca＋Mg-bound P and residual P increased.The evolutions of the proportion of labile inorganic P,Fe＋Al-bound P and Ca＋Mg-bound P were well correlated with the changes of pH value,organic matter and C/N ratio.Therefore,composting could increase the concentration of N and P and decrease the presence of NH 4 ＋-N and labile P fractions which might cause environmental issues following land application.展开更多
The repeated effects of vulnerable habitat and unreasonable human activities on the Bashang Plateau of China led the chestnut soil to degrade. It expresses in reducing soil CEC, decreasing nutrient content, decomposi...The repeated effects of vulnerable habitat and unreasonable human activities on the Bashang Plateau of China led the chestnut soil to degrade. It expresses in reducing soil CEC, decreasing nutrient content, decomposing organic complexes, and reducing humus in loose, steady and tight bond forms, respectively. The percentage of three forms are 21%—34%, 44%—55% and 5%—6.2%, respectively.展开更多
Sequencing batch reactor(SBR)for enhanced biological phosphorus removal(EBPR)processes was used to investigate the impact of the temperature shock on the competition between phosphorus-accumulating organisms(PAOs)and ...Sequencing batch reactor(SBR)for enhanced biological phosphorus removal(EBPR)processes was used to investigate the impact of the temperature shock on the competition between phosphorus-accumulating organisms(PAOs)and glycogen accumulating organisms(GAOs)in start-up stage.During the 34 days operation,SBR was set with temperature variation(0-5 d,22±1℃;6-13 d,29±1℃;14-34 d,14±1℃).PAOs and GAOs were analyzed by fluorescent in situ hybridization(FISH),and intracellular polyphosphate granules were stained by Neisser-stain.The results showed that the influence of temperature shock on PAOs’abundance was more serious than that on GAOs in the enriching process.Under sudden and substantially temperature variation,from 22±1℃ to 29±1℃ and then to 14±1℃,the domination of PAOs was deteriorated.After temperature shock,PAOs’competitive advantages at low temperature that concluded in other study did not appear in our study.As mesophilic,GAOs(indicated by Alphaproteobacteria and Gammaproteobacteria)were more temperature adaptive and better grew and took the domination at 14±1℃ in the end.In the competition process,organisms of tetrad forming organisms(TFOs)-like shape which were considered as typical GAOs,were observed.With the evidence of poly-P granules containing by Neisser-straining and result of FISH,these organisms of TFOs-like shape were better to be assumed as adaption state or a special self-protecting shape of PAOs.展开更多
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment (2012ZX07201004)Jilin Provincial Research Foundation for Basic Research, China (201105033)
文摘The study was conducted to reveal P fractions and N forms changing characters during composting of pig manure with rice straw.During composting,the NH 4 ＋-N concentration decreased and reached at a relatively low value（〈400 mg kg-1） in the final compost,while the NO 3--N concentration increased.Total N losses mainly occurred during thermophilic phase due to the high temperature,the high NH 4 ＋-N concentration and the increase of pH value.Labile inorganic P was dominated in the pig manure and initial compost mixture.During composting,the proportion of labile inorganic P of total extracted P decreased,while the proportion of Fe＋Al-bound P,Ca＋Mg-bound P and residual P increased.The evolutions of the proportion of labile inorganic P,Fe＋Al-bound P and Ca＋Mg-bound P were well correlated with the changes of pH value,organic matter and C/N ratio.Therefore,composting could increase the concentration of N and P and decrease the presence of NH 4 ＋-N and labile P fractions which might cause environmental issues following land application.
文摘The repeated effects of vulnerable habitat and unreasonable human activities on the Bashang Plateau of China led the chestnut soil to degrade. It expresses in reducing soil CEC, decreasing nutrient content, decomposing organic complexes, and reducing humus in loose, steady and tight bond forms, respectively. The percentage of three forms are 21%—34%, 44%—55% and 5%—6.2%, respectively.
基金This research was supported by the National Nature Science Foundation of China(Grant No.50821002,National Creative Research Groups)Mega-Projects of Science Research for Water(No.2008ZX07207-005-003)the National Natural Science Foundation of China(Grant No.50638020).
文摘Sequencing batch reactor(SBR)for enhanced biological phosphorus removal(EBPR)processes was used to investigate the impact of the temperature shock on the competition between phosphorus-accumulating organisms(PAOs)and glycogen accumulating organisms(GAOs)in start-up stage.During the 34 days operation,SBR was set with temperature variation(0-5 d,22±1℃;6-13 d,29±1℃;14-34 d,14±1℃).PAOs and GAOs were analyzed by fluorescent in situ hybridization(FISH),and intracellular polyphosphate granules were stained by Neisser-stain.The results showed that the influence of temperature shock on PAOs’abundance was more serious than that on GAOs in the enriching process.Under sudden and substantially temperature variation,from 22±1℃ to 29±1℃ and then to 14±1℃,the domination of PAOs was deteriorated.After temperature shock,PAOs’competitive advantages at low temperature that concluded in other study did not appear in our study.As mesophilic,GAOs(indicated by Alphaproteobacteria and Gammaproteobacteria)were more temperature adaptive and better grew and took the domination at 14±1℃ in the end.In the competition process,organisms of tetrad forming organisms(TFOs)-like shape which were considered as typical GAOs,were observed.With the evidence of poly-P granules containing by Neisser-straining and result of FISH,these organisms of TFOs-like shape were better to be assumed as adaption state or a special self-protecting shape of PAOs.
