Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit gr...Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit greenhouse gases and particles contributing to haze,and prevention by constructing fire-break canals to reduce fire spread into forest reserves is crucial.This paper aims to determine peat physical and chemical properties near a fire-break canal at different fire frequency areas.Peat sampling was conducted at two forest reserves in Malaysia which represent low fire frequency and high fire frequency areas.The results show that peat properties were not affected by the construction of a fire-break canal,however lignin and cellulose content increased significantly from the distance of the canal in both areas.The study concluded that fire frequency did not significantly influence peat properties except for porosity.The higher fibre content in the high frequency area did not influence moisture content nor the ability to regain moisture.Thus,fire frequency might contribute differently to changes in physical and chemical properties,hence management efforts to construct fire-break canals and restoration efforts should protect peatlands from further degradation.These findings will benefit future management and planning for forest reserves.展开更多
The main soil type, principle contributor of nutrients and available agricultural land in the Hula Valley is the organic Peat. Nevertheless, the relative contribution of Phosphorus from the Hula Valley to the Lake Kin...The main soil type, principle contributor of nutrients and available agricultural land in the Hula Valley is the organic Peat. Nevertheless, the relative contribution of Phosphorus from the Hula Valley to the Lake Kinneret inputs is lower than regional outsourcing. The Nitrogenic matter, mostly Nitrate migration from the Peat soil is significant. The implementation of efficient development is the key factor of Hula Land use. The financial beneficial success of the Hula land use is therefore dependent of Peat soil properties. The porosity of the Peat Soil is high and preferential pathway volume is low and Hydraulic Conductivity is therefore low. Consequently, the Mobile Spray Irrigation line was found as most suitable for cultivation in Peat Soil. Enhancement of Summer irrigation creating moisture elevation reduces Phosphorus migration from Peat Soil and is therefore recommended and recently implemented.展开更多
To investigate the influence of diagenetic water media on the hydrogen isotopes of individual sedimentary aromatic compounds,a series of hydrous pyrolyses were conducted on herbaceous peat.Polycyclic aromatic hydrocar...To investigate the influence of diagenetic water media on the hydrogen isotopes of individual sedimentary aromatic compounds,a series of hydrous pyrolyses were conducted on herbaceous peat.Polycyclic aromatic hydrocarbons(PAHs)in hydrous pyrolysed samples and their hydrogen isotopic composition characteristics were studied.The aqueous medium demonstrated a significant influence on the hydrogen isotopic composition of the individual PAHs generated during pyrolysis.The results showed that the PAHs formed after pyrolysis in the presence of a saltwater medium with high δD value from a salt lake had a heavy hydrogen isotopic composition.The PAHs formed after pyrolysis in the presence of a fresh water medium with low δD value from a swamp had a light hydrogen isotopic composition.The difference in the average PAHδD value between the two hydrous experiments varied from -174‰ to -109‰,suggesting that the hydrogen isotopic composition of individual sedimentary PAHs can reflect the source of the diagenetic water medium.In addition,a comparative study found that the hydrogen isotopes of PAHs were superior to those of n-alkanes in the same sample for diagenetic water indications.The results indicated that the exchange of water-derived inorganic hydrogen and organic hydrogen was more intensive in freshwater experiments than in saltwater experiments.With an increase in the simulation temperature,the average δD value of PAHs generated in the hydrous simulation experiments showed an increasing trend,reflecting that the δD value of sedimentary PAHs formed with the participation of diagenetic water media was still closely related to the thermal maturity of organic matter.Comparative studies showed that theδD values of different types of organic compounds produced by hydrous pyrolysis of peat were in the order,PAHs>n-alkanes>methane.展开更多
This study aimed to the molecular identification of isolated bacteria from the soils of Likouala (Congo-Brazzaville) peat bog area. Counting and isolation were carried out on Mossel and TSB media enriched with petrole...This study aimed to the molecular identification of isolated bacteria from the soils of Likouala (Congo-Brazzaville) peat bog area. Counting and isolation were carried out on Mossel and TSB media enriched with petroleum and vegetable oil;the amplification and sequencing of 16S RNA genes by PCR and Artic Oxford Nanopore Technology. The results showed bacterial loads of (5.81 ± 1.08) × 10<sup>4</sup>;(6.64 ± 1.94) × 10<sup>4</sup> et (8.56 ± 1.19) × 10<sup>3</sup> CFU/g on Mossel respectively for samples 1, 2 and 3 against (2.12 ± 4.1) × 10<sup>8</sup> et (8.15 ± 10.1) × 10<sup>7</sup> CFU/g respectively on TSB enriched with petroleum and vegetable oil exclusively with sample 2. The analysis of the 16S rRNA of the isolates gene made it possible, after PCR, agarose gel electrophoresis, sequencing and bioinformatics analysis, to identify eight (08) strains with similarities of 99 to 100% whose sequences genes placed in GenBank have made it possible to obtain accession numbers corresponding to: Bacillus thuringiensis strain (ON303633);Bacillus cereus strain (ON350770);Bacillus thuringiensis strain (ON350771);Bacillus thuringiensis strain (ON738723);Priestia megaterium strain (ON738719);Bacillus anthracis strain (ON738720);Bacillus subtilis (ON738721);Enterobacter sp (ON738722). The phylogenetic classification of strains was done and revealed two genuses which are Bacillus and Enterobacteriaceae.展开更多
Peatlands,as a special type of wetland,occupy only 3%of the Earth’s surface,but bear about one-third of the world’s soil carbon storage and play an important role in the global carbon cycle.The Zoige Wetland is loca...Peatlands,as a special type of wetland,occupy only 3%of the Earth’s surface,but bear about one-third of the world’s soil carbon storage and play an important role in the global carbon cycle.The Zoige Wetland is located on the eastern edge of the Qinghai-Tibet Plateau,and its peat reserves are up to 1.9 billion tons,accounting for more than 40%of the country’s peat resources,which is an important support for China to achieve the“double carbon”goal.This paper reviews the research status and storage estimation of soil organic carbon in Zoige Wetland.The statistical results show that there is a large difference in the estimation of carbon storage in the peatland of Zoige(0.43-1.42 Pg).The reasons are mainly related to marked differences in values reported for soil densities,organic carbon levels,and accumulation rates.There are still great uncertainties in the estimation of wetland carbon stocks,and future studies should focus on reducing soil carbon sink uncertainties,climate change,the impact of permafrost melting on carbon sink functions,the impact of degraded ecosystem restoration and sink enhancement pathways,and other greenhouse gas functions.In order to accurately reveal the current situation and future trend of carbon sink in peat wetlands,a model-multi-source observation data fusion system was constructed to complement the observation shortcomings in key areas,and provide reference and support for the construction of carbon neutral ecological civilization.展开更多
Peat and peatified wood are significant carbohydrate resources in tropical rainforests. The carbohydrates of cellulose and hemicellulose are important sources of monosaccharides for both vital activities and industria...Peat and peatified wood are significant carbohydrate resources in tropical rainforests. The carbohydrates of cellulose and hemicellulose are important sources of monosaccharides for both vital activities and industrial applications, such as furan production of furfural and hydroxymethyl furfural. Hydrothermal treatment at 200°C and ultrasonic irradiation pretreatment were used to recover monosaccharides from the abovementioned resources. The monosaccharide recovery from peat was shown to be higher than that from peatified wood. The conversion to organic acids is considered to proceed rapidly because acids are always detected with monosaccharides. This conversion is outstripped by the organic acid-to-gas reaction for treatment times longer than 20 min. The monosaccharide recovery from peatified wood was improved by the ultrasonication pretreatment. It is considered that ultrasonic irradiation broke down lignin blockages, enabling water molecules to access the carbohydrates more easily in the subsequent hydrothermal treatment.展开更多
Tropic and sub-tropic tidal flats (generalised) are a kind of speific peat-forming environments. Taking the Mangrove tidal flats and mangrove pets in Hainan island as a example, the authors deeply study and discuss th...Tropic and sub-tropic tidal flats (generalised) are a kind of speific peat-forming environments. Taking the Mangrove tidal flats and mangrove pets in Hainan island as a example, the authors deeply study and discuss the peat-forming mechanism of tropic and sub-tropic tidal flats. The conclusions are as follows: intrusion accretiou of plant organic matter is more important ; the organic matter has accumulated witk high productivity, high return rate and high decompeition rate ;anaerobic bacterin play a more important role during early peatification ; sea level change is the fundameutal factor controlling the formation and evolution of tidal flat peat-forming environments; lagoon peat-flat and delta peat-flat are main types of tidal flat peat-forming euvironments ;tidal flat peat-forming environments are remarkably characterized by low-level and rabe properties.展开更多
Field surveys indicate lateral variation in peat humification levels (von Post) in dominantly occurring fibric,fibric to hemic,sapric and hemie to sapric peats across a gradient from the margin towards the centre of...Field surveys indicate lateral variation in peat humification levels (von Post) in dominantly occurring fibric,fibric to hemic,sapric and hemie to sapric peats across a gradient from the margin towards the centre of tropical lowland peat domes.Cement-peat stabilisation can be enhanced by adding mineral soil fillers (silt,clays and fine sands) obtained from Quaternary floodplain deposits and residual soil (weathered schist).The unconfined compressive strength (UCS) of the stabilised cement-mineral soil fifler-peat mix increases with the increased addition of selected mineral soil filler.Lateral variation in the stabilised peat strength (UCS) in the top 0 to 0.5 m layer was found from the margin towards the centre of the tropical lowland peat dome.The variations in the UCS of stabilised tropical lowland peats along a gradient from the periphery towards the centre of the peat dome are most likely caused by a combination of factors due to variations in the mineral soil or ash content of the peat and horizontal zonation or lateral variation in the dominant species of the plant assemblages (due to successive vegetation zonation of the peat swamp forest from the periphery towards the centre of the tropical lowland peat dome).展开更多
In order to enhance the nitrogen removal, a subsurface wastewater infiltration system (SWIS) was improved by adding peat in deep soil as carbon source for denitrification process. The effects of addition of carbon s...In order to enhance the nitrogen removal, a subsurface wastewater infiltration system (SWIS) was improved by adding peat in deep soil as carbon source for denitrification process. The effects of addition of carbon source in the underpart of the SWIS on nitrogen removal at different influents (with the total nitrogen (TN) concentration 40 and 80 mg L^-1, respectively) were investigated by soil column simulating experiments. When the relatively light pollution influent with 40 mg L^-1 TN was used, the average concentrations of NO3-N and TN in effluents were (4.69±0.235), (6.18±0.079) mg L^-1, respectively, decreased by 32 and 30.8% than the control; the NO3--N concentration of all effluents was below the maximum contaminant level of 10 mg L^-1; as high as 92.67% of the TN removal efficiency was achieved. When relatively heavy pollution influent with 80 mg LITN was used, the average concentrations of NO3--N and TN in effluents were (10.2±0.265), (12.5±0.148) mg L^-1 respectively, decreased by 20 and 21.2% than the control; the NO3--N concentration of all effluents met the grade Ⅲ of the national quality standard for ground water of China (GB/T 14848-1993) with the values less than 20 mg L^-1; the TN removal efficiency of 94.1% was achieved. In summary, adding peat in the underpart of the SWIS significantly decreased TN and NO3- -N concentration in effluents and the nitrogen removal efficiency improved significantly.展开更多
Floating tephra was deposited together with ice core, snow layer, abyssal sediment, lake sediments, and other geological records. It is of great significance to interpret the impact on the climate change of volcanic e...Floating tephra was deposited together with ice core, snow layer, abyssal sediment, lake sediments, and other geological records. It is of great significance to interpret the impact on the climate change of volcanic eruptions from these geological records. It is the first time that volcanic glass was discovered from the peat of Jinchuan (金川) Maar, Jilin (吉林) Province, China. And it is in situ sediments from a near-source explosive eruption according to particle size analysis and identification results. The tephra were neither from Tianchi (天池) volcano eruptions, Changbai (长白) Mountain, nor from Jinlongdingzi (金龙顶子) volcano about 1 600 aBP eruption, but maybe from an unknown eruption of Longgang (龙岗) volcano group according to their geochemistry and distribution. Geochemical characters of the tephra are similar to those of Jinglongdingzi, which are poor in silica, deficient in alkali, Na2O content is more than K2O content, and are similar to distribution patterns of REE and incompatible elements, which helps to speculate that they originated from the same mantle magma with rare condemnation, and from basaltic explosive eruption of Longgang volcano group. The tephra, from peat with age proved that the eruption possibly happened in 15 BC-26 AD, is one of Longgang volcano group eruption that was not recorded and is earlier than that of Jinglongdingzi about 1 600 aBP eruption. And the sedimentary time of tephra is during the period of low temperature alteration, which may be the influence of eruption toward the local climate according to the correlativity of eruption to local temperature curve of peat cellulose oxygen isotope.展开更多
In terms of macrolithotypes and microlithotypes, the petrographic composition was determined on column samples of Permian Seam 2 and Carboniferous Seam 9(2) from the Xingtai Coalfield, China. The macrolithotypes are c...In terms of macrolithotypes and microlithotypes, the petrographic composition was determined on column samples of Permian Seam 2 and Carboniferous Seam 9(2) from the Xingtai Coalfield, China. The macrolithotypes are classified into bright coal (B), banded bright coal (BB), banded coal (BC),banded dull coal (BD), dull coal (D) and fibrous coal (F). The lithotypes are dominated by BD and D in Seam 2, and BB in Seam 9(2).Microlithotypes are dominated by inertite and durite in Seam 2 and by vitrite in Seam 9(2). Eight microlithotypes were selected as indicators of peat-forming environments. Two triangle diagrams were drawn based on the indicators in order to explicate the peat-forming environments of Permian Seam 2 and Carboniferous Seam 9(2). The results indicate that the peat of Carboniferous Seam 9(2) was formed dominantly in wet swamps, whereas tbe peat of Permian Seam 2 formed dominantly in dry and wet swamps. These results are agree with the regional geology, that is, the peat of Carboniferous Seam 9(2) was formed in a transition zone and the peat of Permian Seam 2 formed in an upper delta zone.The climate of the peat-forming time for Permian Seam 2 was drier than that for Carboniferous.展开更多
To predict future spatio-temporal patterns of climate change, we should fully understand the spatio-temporal patterns of climate change during the past millennium. But, we are not yet able to delineate the patterns be...To predict future spatio-temporal patterns of climate change, we should fully understand the spatio-temporal patterns of climate change during the past millennium. But, we are not yet able to delineate the patterns because the qualities of the retrieved proxy records and the spatial coverage of those records are not adequate. Northern Xinjiang of China is one of such areas where the records are not adequate. Here, we present a 500-yr land-surface moisture sequence from Heiyangpo Peat(48.34°N, 87.18°E, 1353 m a.s.l) in the southern Altai Mountains within northern Xinjiang. Specifically, peat carbon isotope value of cellulose(δ^(13)C_(cellulose)) was used to estimate the warm-season moisture variations and the degree of humification was used to constrain the δ^(13)C_(cellulose)-based hydrological interpretation. The climatic attributions of the interpreted hydrological variations were based on the warm-season temperature reconstructed from Belukha ice core and the warm-season precipitation inferred from the reconstructed Atlantic Multidecadal Oscillations(AMO). The results show that humification decreased and the δ^(13)C_(celluose)-suggested moisture decreased from ~1510 to ~1775 AD, implying that a constant dryingcondition may have inhibited peat decay. Our comparison with reconstructed climatic parameters suggests that the moisture-level decline was most likely resulted from a constant decline of precipitation. The results also show that humification kept a stable level and the δ^(13)C_(celluose)-suggested moisture also decreased from ~1775 to ~2013 AD, implying that peat decay in the acrotelm primarily did not depend on the water availability or an aerobic environment. Again, our comparison with reconstructed climatic parameters suggests that the land-surface moisturelevel decline was most likely resulted from a steady warming of growing-season temperature.展开更多
基金This research was funded by the Ministry of Higher Education Malaysia via the Fundamental Research Grant Scheme(FRGS/1/2020/WAB03/UPM/02/1)。
文摘Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit greenhouse gases and particles contributing to haze,and prevention by constructing fire-break canals to reduce fire spread into forest reserves is crucial.This paper aims to determine peat physical and chemical properties near a fire-break canal at different fire frequency areas.Peat sampling was conducted at two forest reserves in Malaysia which represent low fire frequency and high fire frequency areas.The results show that peat properties were not affected by the construction of a fire-break canal,however lignin and cellulose content increased significantly from the distance of the canal in both areas.The study concluded that fire frequency did not significantly influence peat properties except for porosity.The higher fibre content in the high frequency area did not influence moisture content nor the ability to regain moisture.Thus,fire frequency might contribute differently to changes in physical and chemical properties,hence management efforts to construct fire-break canals and restoration efforts should protect peatlands from further degradation.These findings will benefit future management and planning for forest reserves.
文摘The main soil type, principle contributor of nutrients and available agricultural land in the Hula Valley is the organic Peat. Nevertheless, the relative contribution of Phosphorus from the Hula Valley to the Lake Kinneret inputs is lower than regional outsourcing. The Nitrogenic matter, mostly Nitrate migration from the Peat soil is significant. The implementation of efficient development is the key factor of Hula Land use. The financial beneficial success of the Hula land use is therefore dependent of Peat soil properties. The porosity of the Peat Soil is high and preferential pathway volume is low and Hydraulic Conductivity is therefore low. Consequently, the Mobile Spray Irrigation line was found as most suitable for cultivation in Peat Soil. Enhancement of Summer irrigation creating moisture elevation reduces Phosphorus migration from Peat Soil and is therefore recommended and recently implemented.
基金supported by the National Natural Science Foundation of China(Grant Nos.41972110 and 41772108)。
文摘To investigate the influence of diagenetic water media on the hydrogen isotopes of individual sedimentary aromatic compounds,a series of hydrous pyrolyses were conducted on herbaceous peat.Polycyclic aromatic hydrocarbons(PAHs)in hydrous pyrolysed samples and their hydrogen isotopic composition characteristics were studied.The aqueous medium demonstrated a significant influence on the hydrogen isotopic composition of the individual PAHs generated during pyrolysis.The results showed that the PAHs formed after pyrolysis in the presence of a saltwater medium with high δD value from a salt lake had a heavy hydrogen isotopic composition.The PAHs formed after pyrolysis in the presence of a fresh water medium with low δD value from a swamp had a light hydrogen isotopic composition.The difference in the average PAHδD value between the two hydrous experiments varied from -174‰ to -109‰,suggesting that the hydrogen isotopic composition of individual sedimentary PAHs can reflect the source of the diagenetic water medium.In addition,a comparative study found that the hydrogen isotopes of PAHs were superior to those of n-alkanes in the same sample for diagenetic water indications.The results indicated that the exchange of water-derived inorganic hydrogen and organic hydrogen was more intensive in freshwater experiments than in saltwater experiments.With an increase in the simulation temperature,the average δD value of PAHs generated in the hydrous simulation experiments showed an increasing trend,reflecting that the δD value of sedimentary PAHs formed with the participation of diagenetic water media was still closely related to the thermal maturity of organic matter.Comparative studies showed that theδD values of different types of organic compounds produced by hydrous pyrolysis of peat were in the order,PAHs>n-alkanes>methane.
文摘This study aimed to the molecular identification of isolated bacteria from the soils of Likouala (Congo-Brazzaville) peat bog area. Counting and isolation were carried out on Mossel and TSB media enriched with petroleum and vegetable oil;the amplification and sequencing of 16S RNA genes by PCR and Artic Oxford Nanopore Technology. The results showed bacterial loads of (5.81 ± 1.08) × 10<sup>4</sup>;(6.64 ± 1.94) × 10<sup>4</sup> et (8.56 ± 1.19) × 10<sup>3</sup> CFU/g on Mossel respectively for samples 1, 2 and 3 against (2.12 ± 4.1) × 10<sup>8</sup> et (8.15 ± 10.1) × 10<sup>7</sup> CFU/g respectively on TSB enriched with petroleum and vegetable oil exclusively with sample 2. The analysis of the 16S rRNA of the isolates gene made it possible, after PCR, agarose gel electrophoresis, sequencing and bioinformatics analysis, to identify eight (08) strains with similarities of 99 to 100% whose sequences genes placed in GenBank have made it possible to obtain accession numbers corresponding to: Bacillus thuringiensis strain (ON303633);Bacillus cereus strain (ON350770);Bacillus thuringiensis strain (ON350771);Bacillus thuringiensis strain (ON738723);Priestia megaterium strain (ON738719);Bacillus anthracis strain (ON738720);Bacillus subtilis (ON738721);Enterobacter sp (ON738722). The phylogenetic classification of strains was done and revealed two genuses which are Bacillus and Enterobacteriaceae.
基金2023 financial research project of Sichuan Research Institute of Geological Survey“Carbon Storage Monitoring of Wetland Ecosystem in Northwest Sichuan Plateau based on Big Data and expert Knowledge” (SCIGS-CYBXM-2023014).
文摘Peatlands,as a special type of wetland,occupy only 3%of the Earth’s surface,but bear about one-third of the world’s soil carbon storage and play an important role in the global carbon cycle.The Zoige Wetland is located on the eastern edge of the Qinghai-Tibet Plateau,and its peat reserves are up to 1.9 billion tons,accounting for more than 40%of the country’s peat resources,which is an important support for China to achieve the“double carbon”goal.This paper reviews the research status and storage estimation of soil organic carbon in Zoige Wetland.The statistical results show that there is a large difference in the estimation of carbon storage in the peatland of Zoige(0.43-1.42 Pg).The reasons are mainly related to marked differences in values reported for soil densities,organic carbon levels,and accumulation rates.There are still great uncertainties in the estimation of wetland carbon stocks,and future studies should focus on reducing soil carbon sink uncertainties,climate change,the impact of permafrost melting on carbon sink functions,the impact of degraded ecosystem restoration and sink enhancement pathways,and other greenhouse gas functions.In order to accurately reveal the current situation and future trend of carbon sink in peat wetlands,a model-multi-source observation data fusion system was constructed to complement the observation shortcomings in key areas,and provide reference and support for the construction of carbon neutral ecological civilization.
文摘Peat and peatified wood are significant carbohydrate resources in tropical rainforests. The carbohydrates of cellulose and hemicellulose are important sources of monosaccharides for both vital activities and industrial applications, such as furan production of furfural and hydroxymethyl furfural. Hydrothermal treatment at 200°C and ultrasonic irradiation pretreatment were used to recover monosaccharides from the abovementioned resources. The monosaccharide recovery from peat was shown to be higher than that from peatified wood. The conversion to organic acids is considered to proceed rapidly because acids are always detected with monosaccharides. This conversion is outstripped by the organic acid-to-gas reaction for treatment times longer than 20 min. The monosaccharide recovery from peatified wood was improved by the ultrasonication pretreatment. It is considered that ultrasonic irradiation broke down lignin blockages, enabling water molecules to access the carbohydrates more easily in the subsequent hydrothermal treatment.
文摘Tropic and sub-tropic tidal flats (generalised) are a kind of speific peat-forming environments. Taking the Mangrove tidal flats and mangrove pets in Hainan island as a example, the authors deeply study and discuss the peat-forming mechanism of tropic and sub-tropic tidal flats. The conclusions are as follows: intrusion accretiou of plant organic matter is more important ; the organic matter has accumulated witk high productivity, high return rate and high decompeition rate ;anaerobic bacterin play a more important role during early peatification ; sea level change is the fundameutal factor controlling the formation and evolution of tidal flat peat-forming environments; lagoon peat-flat and delta peat-flat are main types of tidal flat peat-forming euvironments ;tidal flat peat-forming environments are remarkably characterized by low-level and rabe properties.
基金the IPPP grant PV018-2011A for financial support from the University of Malaya
文摘Field surveys indicate lateral variation in peat humification levels (von Post) in dominantly occurring fibric,fibric to hemic,sapric and hemie to sapric peats across a gradient from the margin towards the centre of tropical lowland peat domes.Cement-peat stabilisation can be enhanced by adding mineral soil fillers (silt,clays and fine sands) obtained from Quaternary floodplain deposits and residual soil (weathered schist).The unconfined compressive strength (UCS) of the stabilised cement-mineral soil fifler-peat mix increases with the increased addition of selected mineral soil filler.Lateral variation in the stabilised peat strength (UCS) in the top 0 to 0.5 m layer was found from the margin towards the centre of the tropical lowland peat dome.The variations in the UCS of stabilised tropical lowland peats along a gradient from the periphery towards the centre of the peat dome are most likely caused by a combination of factors due to variations in the mineral soil or ash content of the peat and horizontal zonation or lateral variation in the dominant species of the plant assemblages (due to successive vegetation zonation of the peat swamp forest from the periphery towards the centre of the tropical lowland peat dome).
基金supported by the Key Technologies R&D Program of China during the 11th Five-Year Plan period (2008BADC4B17 and 2006 BAD16B09)the Beijing Key Discipline Construction Project of Biomass Engineering Interdisciplinary
文摘In order to enhance the nitrogen removal, a subsurface wastewater infiltration system (SWIS) was improved by adding peat in deep soil as carbon source for denitrification process. The effects of addition of carbon source in the underpart of the SWIS on nitrogen removal at different influents (with the total nitrogen (TN) concentration 40 and 80 mg L^-1, respectively) were investigated by soil column simulating experiments. When the relatively light pollution influent with 40 mg L^-1 TN was used, the average concentrations of NO3-N and TN in effluents were (4.69±0.235), (6.18±0.079) mg L^-1, respectively, decreased by 32 and 30.8% than the control; the NO3--N concentration of all effluents was below the maximum contaminant level of 10 mg L^-1; as high as 92.67% of the TN removal efficiency was achieved. When relatively heavy pollution influent with 80 mg LITN was used, the average concentrations of NO3--N and TN in effluents were (10.2±0.265), (12.5±0.148) mg L^-1 respectively, decreased by 20 and 21.2% than the control; the NO3--N concentration of all effluents met the grade Ⅲ of the national quality standard for ground water of China (GB/T 14848-1993) with the values less than 20 mg L^-1; the TN removal efficiency of 94.1% was achieved. In summary, adding peat in the underpart of the SWIS significantly decreased TN and NO3- -N concentration in effluents and the nitrogen removal efficiency improved significantly.
基金the National Natural Science Foundation of China (Nos. 40231007, 40602031)the Open Research Foundation of the State Key Laboratory of Environmental Geochemistry,Chinese Academy of Sciences (SKEGL2003010)
文摘Floating tephra was deposited together with ice core, snow layer, abyssal sediment, lake sediments, and other geological records. It is of great significance to interpret the impact on the climate change of volcanic eruptions from these geological records. It is the first time that volcanic glass was discovered from the peat of Jinchuan (金川) Maar, Jilin (吉林) Province, China. And it is in situ sediments from a near-source explosive eruption according to particle size analysis and identification results. The tephra were neither from Tianchi (天池) volcano eruptions, Changbai (长白) Mountain, nor from Jinlongdingzi (金龙顶子) volcano about 1 600 aBP eruption, but maybe from an unknown eruption of Longgang (龙岗) volcano group according to their geochemistry and distribution. Geochemical characters of the tephra are similar to those of Jinglongdingzi, which are poor in silica, deficient in alkali, Na2O content is more than K2O content, and are similar to distribution patterns of REE and incompatible elements, which helps to speculate that they originated from the same mantle magma with rare condemnation, and from basaltic explosive eruption of Longgang volcano group. The tephra, from peat with age proved that the eruption possibly happened in 15 BC-26 AD, is one of Longgang volcano group eruption that was not recorded and is earlier than that of Jinglongdingzi about 1 600 aBP eruption. And the sedimentary time of tephra is during the period of low temperature alteration, which may be the influence of eruption toward the local climate according to the correlativity of eruption to local temperature curve of peat cellulose oxygen isotope.
文摘In terms of macrolithotypes and microlithotypes, the petrographic composition was determined on column samples of Permian Seam 2 and Carboniferous Seam 9(2) from the Xingtai Coalfield, China. The macrolithotypes are classified into bright coal (B), banded bright coal (BB), banded coal (BC),banded dull coal (BD), dull coal (D) and fibrous coal (F). The lithotypes are dominated by BD and D in Seam 2, and BB in Seam 9(2).Microlithotypes are dominated by inertite and durite in Seam 2 and by vitrite in Seam 9(2). Eight microlithotypes were selected as indicators of peat-forming environments. Two triangle diagrams were drawn based on the indicators in order to explicate the peat-forming environments of Permian Seam 2 and Carboniferous Seam 9(2). The results indicate that the peat of Carboniferous Seam 9(2) was formed dominantly in wet swamps, whereas tbe peat of Permian Seam 2 formed dominantly in dry and wet swamps. These results are agree with the regional geology, that is, the peat of Carboniferous Seam 9(2) was formed in a transition zone and the peat of Permian Seam 2 formed in an upper delta zone.The climate of the peat-forming time for Permian Seam 2 was drier than that for Carboniferous.
基金financially supported by Chinese Natural Science International Cooperation Program Foundation Grant (No. 41361140361)Chinese Natural Science Foundation Grant (No. U1203821L08)Chinese Academy Sciences International Cooperation Program (No. GJHZ201315)
文摘To predict future spatio-temporal patterns of climate change, we should fully understand the spatio-temporal patterns of climate change during the past millennium. But, we are not yet able to delineate the patterns because the qualities of the retrieved proxy records and the spatial coverage of those records are not adequate. Northern Xinjiang of China is one of such areas where the records are not adequate. Here, we present a 500-yr land-surface moisture sequence from Heiyangpo Peat(48.34°N, 87.18°E, 1353 m a.s.l) in the southern Altai Mountains within northern Xinjiang. Specifically, peat carbon isotope value of cellulose(δ^(13)C_(cellulose)) was used to estimate the warm-season moisture variations and the degree of humification was used to constrain the δ^(13)C_(cellulose)-based hydrological interpretation. The climatic attributions of the interpreted hydrological variations were based on the warm-season temperature reconstructed from Belukha ice core and the warm-season precipitation inferred from the reconstructed Atlantic Multidecadal Oscillations(AMO). The results show that humification decreased and the δ^(13)C_(celluose)-suggested moisture decreased from ~1510 to ~1775 AD, implying that a constant dryingcondition may have inhibited peat decay. Our comparison with reconstructed climatic parameters suggests that the moisture-level decline was most likely resulted from a constant decline of precipitation. The results also show that humification kept a stable level and the δ^(13)C_(celluose)-suggested moisture also decreased from ~1775 to ~2013 AD, implying that peat decay in the acrotelm primarily did not depend on the water availability or an aerobic environment. Again, our comparison with reconstructed climatic parameters suggests that the land-surface moisturelevel decline was most likely resulted from a steady warming of growing-season temperature.