A number of paddy fields pertaining to the Majiabang Cultures (5500-3800 years BC) were discovered during the archaeological excavations that were carried out since 1998 at the Chuodun site in the Yangtze River Delta....A number of paddy fields pertaining to the Majiabang Cultures (5500-3800 years BC) were discovered during the archaeological excavations that were carried out since 1998 at the Chuodun site in the Yangtze River Delta. The pollen and phytolith analyses of two soil profiles from the northeastern part of this site were carried out to trace the agricultural practices of the Neolithic period. The phytolith results showed that rice domestication in the Yangtze River Delta could be traced back to as early as the Majiabang Culture. The pollen assemblage also revealed low levels of aquatic species, similar to that in modern paddy fields. This finding suggested that humans might have removed weeds for rice cultivation during the Neolithic period. Thus, pollen analysis in association with phytolith analysis was a promising method for identifying ancient paddy fields.展开更多
The leaching characteristics of a garden soil may be greatly affected by application of poultry and livestock manures from intensive farming.Packed soil columns of a garden soil (CK) and the soils after respectively r...The leaching characteristics of a garden soil may be greatly affected by application of poultry and livestock manures from intensive farming.Packed soil columns of a garden soil (CK) and the soils after respectively receiving 2% pig manure (PM),chicken manure (CM),and commercial organic manure (OM) were leached with 0.05 mol L^(-1) Ca(NO_3)_2 and 0.01 mol L^(-1) EDTA solutions.The leachate EC (electric conductivity) values gradually increased at the beginning and then reached a stable value when the soil columns were leached with 0.05 mol L^(-1) Ca(NO_3)_2 solution.The leachate EC values showed a peak-shape when leached with 0.01 mol L^(-1) EDTA solution.In all the soil columns,the pH values of the leachates decreased with increase of displacement volumes when the Ca(NO_3)_2 solution was used.The total amounts of Cu and Zn eluted from the four soil columns were significantly correlated with the extracted soil Cu and Zn concentrations by 1.0 mol L^(-1) NH_4NO_3,but were not correlated with the leachate dissolved organic carbon (DOC) contents.The Zn concentration in the leachate of the PM-treated soil column with 0.05 mol L^(-1) Ca(NO_3)_2 solution was above the Quality StandardⅢfor Ground Water of China (GB/T 14848-93,Zn<1.0 mg L^(-1)).When compared with 0.05 mol L^(-1) Ca(NO_3)_2,the EDTA solution significantly accelerated Cu and Zn elutions in the manure-treated columns.This suggested that applying poultry and livestock manures from intensive farming to farmland might pose a threat to the groundwater quality.展开更多
Field investigation and laboratory analysis of 22 ancient paddy soils excavated at Chuodun site, Kunshan City, Jiangsu Province, China were carried out in 2003 to (1) understand the basic characteristics of ancient pa...Field investigation and laboratory analysis of 22 ancient paddy soils excavated at Chuodun site, Kunshan City, Jiangsu Province, China were carried out in 2003 to (1) understand the basic characteristics of ancient paddy soils, (2) compare the difference of soil fertility between ancient paddy soils and recent paddy soils, and (3) inquire into mechanisms of the sustainability of paddy soil. The oldest paddy soils at Chuodun site can be dated back to Neolithic age, around 6 000 aBP. These ancient fields were buried in about 1-m deep from the soil surface and their areas ranged from 0.32 to 12.9 m2 with an average of 5.2 m2. The paddy soils with > 5 000 pellets phytolith g-1 soil were termed intensively cultivated paddy soils (ICPS) and those with < 5 000 pellets phytolith g-1 soil were called weakly cultivated soils (WCPS). The contents of organic carbon (OC), and total N in the former were significantly higher than that in the latter. Ancient paddy soils had higher soil pH and C/N, total and available P, and lower contents of OC, DOC, total N, S, Cu, Fe, and available K, S, Fe, Mn, and Cu compared with recent paddy soils, which were attributed to application of chemical and manure fertilizers, pollution and acidification in recent paddy soils. The variation coefficients of OC and other nutrients in ancient paddy soils with higher PI were greater than that in ancient paddy soils with low PI, which indicated that human activities had a great impact on the spatial variability of soil nutrients. The contents of OC, total N, P and S in ancient paddy soils were higher than that in ancient moss of the same age, which indicated that planting rice during Majiabang culture period was beneficial to the accumulation of those life elements.展开更多
An E3 ubiquitin ligase gene(Genbank accession no.:MD01 G1010900) was cloned from the Royal Gala apple genome(Malus×domestica Borkh.).Sequence analysis showed that the length of the MdPUB29 gene was 1 275 bp,encod...An E3 ubiquitin ligase gene(Genbank accession no.:MD01 G1010900) was cloned from the Royal Gala apple genome(Malus×domestica Borkh.).Sequence analysis showed that the length of the MdPUB29 gene was 1 275 bp,encoding 424 amino acids.Phylogenetic tree analysis indicated that the apple E3 ubiquitin ligase exhibited the greatest sequence similarity to Pyrus×bretschneideri.The predicted protein structural domain of MdPUB29 showed that it contained a U-box domain.qRT-PCR analysis showed that Md PUB29 was expressed widely in different tissues of the Royal Gala apple species,and was highly expressed in the root,while the expression of MdPUB29 was significantly inhibited by exogenous NaCl.Immunoblotting assays revealed that MdPUB29 protein abundance in tissue cultures of the Royal Gala apple accumulated under NaC l stress conditions.Three-dimensional protein structure prediction indicated that MdPUB29 was highly homologous with AtPUB29.The growing potential of MdPUB29-expressing apple calli and Arabidopsis were much stronger than that of the control under salt stress conditions,suggesting that MdPUB29 may positively regulate salt tolerance.展开更多
基金Project supported by the National Natural Science Foundation of China (Nos. DO115-40335047, D0101-40401002, and D0218-40572178)the National Basic Research and Development Program of China (No. 2002CB410805).
文摘A number of paddy fields pertaining to the Majiabang Cultures (5500-3800 years BC) were discovered during the archaeological excavations that were carried out since 1998 at the Chuodun site in the Yangtze River Delta. The pollen and phytolith analyses of two soil profiles from the northeastern part of this site were carried out to trace the agricultural practices of the Neolithic period. The phytolith results showed that rice domestication in the Yangtze River Delta could be traced back to as early as the Majiabang Culture. The pollen assemblage also revealed low levels of aquatic species, similar to that in modern paddy fields. This finding suggested that humans might have removed weeds for rice cultivation during the Neolithic period. Thus, pollen analysis in association with phytolith analysis was a promising method for identifying ancient paddy fields.
基金Project supported by the Knowledge Innovative Program of Chinese Academy of Sciences (Nos.KZCX3-SW-435 and KZCX2-YW-404)the Natural Science Foundation of Jiangsu Province (No.BK2004219).
文摘The leaching characteristics of a garden soil may be greatly affected by application of poultry and livestock manures from intensive farming.Packed soil columns of a garden soil (CK) and the soils after respectively receiving 2% pig manure (PM),chicken manure (CM),and commercial organic manure (OM) were leached with 0.05 mol L^(-1) Ca(NO_3)_2 and 0.01 mol L^(-1) EDTA solutions.The leachate EC (electric conductivity) values gradually increased at the beginning and then reached a stable value when the soil columns were leached with 0.05 mol L^(-1) Ca(NO_3)_2 solution.The leachate EC values showed a peak-shape when leached with 0.01 mol L^(-1) EDTA solution.In all the soil columns,the pH values of the leachates decreased with increase of displacement volumes when the Ca(NO_3)_2 solution was used.The total amounts of Cu and Zn eluted from the four soil columns were significantly correlated with the extracted soil Cu and Zn concentrations by 1.0 mol L^(-1) NH_4NO_3,but were not correlated with the leachate dissolved organic carbon (DOC) contents.The Zn concentration in the leachate of the PM-treated soil column with 0.05 mol L^(-1) Ca(NO_3)_2 solution was above the Quality StandardⅢfor Ground Water of China (GB/T 14848-93,Zn<1.0 mg L^(-1)).When compared with 0.05 mol L^(-1) Ca(NO_3)_2,the EDTA solution significantly accelerated Cu and Zn elutions in the manure-treated columns.This suggested that applying poultry and livestock manures from intensive farming to farmland might pose a threat to the groundwater quality.
基金The study was funded by the National Natural Science Foundation of China(40335047).We thank Professor Xu Zhihong,the Faculty of Environmental Science,Griffith University,Australia,for revising this manuscript.
文摘Field investigation and laboratory analysis of 22 ancient paddy soils excavated at Chuodun site, Kunshan City, Jiangsu Province, China were carried out in 2003 to (1) understand the basic characteristics of ancient paddy soils, (2) compare the difference of soil fertility between ancient paddy soils and recent paddy soils, and (3) inquire into mechanisms of the sustainability of paddy soil. The oldest paddy soils at Chuodun site can be dated back to Neolithic age, around 6 000 aBP. These ancient fields were buried in about 1-m deep from the soil surface and their areas ranged from 0.32 to 12.9 m2 with an average of 5.2 m2. The paddy soils with > 5 000 pellets phytolith g-1 soil were termed intensively cultivated paddy soils (ICPS) and those with < 5 000 pellets phytolith g-1 soil were called weakly cultivated soils (WCPS). The contents of organic carbon (OC), and total N in the former were significantly higher than that in the latter. Ancient paddy soils had higher soil pH and C/N, total and available P, and lower contents of OC, DOC, total N, S, Cu, Fe, and available K, S, Fe, Mn, and Cu compared with recent paddy soils, which were attributed to application of chemical and manure fertilizers, pollution and acidification in recent paddy soils. The variation coefficients of OC and other nutrients in ancient paddy soils with higher PI were greater than that in ancient paddy soils with low PI, which indicated that human activities had a great impact on the spatial variability of soil nutrients. The contents of OC, total N, P and S in ancient paddy soils were higher than that in ancient moss of the same age, which indicated that planting rice during Majiabang culture period was beneficial to the accumulation of those life elements.
基金supported by the grants from the National Natural Science Foundation of China(31601728,31471854 and 31772288)the Innovation Team Support Program from the Ministry of Education of China(IRT15R42)+3 种基金the Shandong Natural Science Foundation,China(ZR2016CQ13)the Shandong Modern Agriculture Industry Technology System,China(SDAIT-06-03)the Shandong Agricultural University Outstanding Youth Fund,China(564024)the Shandong Agricultural University Science and Technology Innovation Fund Project,China(24024)
文摘An E3 ubiquitin ligase gene(Genbank accession no.:MD01 G1010900) was cloned from the Royal Gala apple genome(Malus×domestica Borkh.).Sequence analysis showed that the length of the MdPUB29 gene was 1 275 bp,encoding 424 amino acids.Phylogenetic tree analysis indicated that the apple E3 ubiquitin ligase exhibited the greatest sequence similarity to Pyrus×bretschneideri.The predicted protein structural domain of MdPUB29 showed that it contained a U-box domain.qRT-PCR analysis showed that Md PUB29 was expressed widely in different tissues of the Royal Gala apple species,and was highly expressed in the root,while the expression of MdPUB29 was significantly inhibited by exogenous NaCl.Immunoblotting assays revealed that MdPUB29 protein abundance in tissue cultures of the Royal Gala apple accumulated under NaC l stress conditions.Three-dimensional protein structure prediction indicated that MdPUB29 was highly homologous with AtPUB29.The growing potential of MdPUB29-expressing apple calli and Arabidopsis were much stronger than that of the control under salt stress conditions,suggesting that MdPUB29 may positively regulate salt tolerance.
