封育是当前恢复和改良内蒙古草地的重要措施，也是实现草地固碳效应最有效的途径之一。本文利用内蒙古封育32年和自由放牧的羊草草地，分析了其土壤有机碳组分、土壤团聚体和土壤腐殖质组分碳含量的变化，并运用13 C核磁共振波普法对土...封育是当前恢复和改良内蒙古草地的重要措施，也是实现草地固碳效应最有效的途径之一。本文利用内蒙古封育32年和自由放牧的羊草草地，分析了其土壤有机碳组分、土壤团聚体和土壤腐殖质组分碳含量的变化，并运用13 C核磁共振波普法对土壤腐殖质的有机碳组分进行波普分析，探讨了长期封育对羊草草地土壤有机碳组分和土壤有机质结构的影响，期望能为科学地评估长期封育状况下草地固碳效应及其稳定性提供理论依据。实验结果表明：长期封育显著提高了草地土壤有机碳含量；在土壤有机碳组分中，除土壤微生物碳（MBC ）含量降低外，其碳组分含量都相应增加。其中，易氧化有机碳（EOC）含量增加最为明显，长期封育草地是自由放牧草地土壤的4．53倍；长期封育显著提高了草地土壤0．25～2 mm 团聚体所占比例及其有机碳含量；长期封育提高了草地土壤腐殖质中的胡敏酸碳（HAC）、胡敏素碳（HUC）含量和胡敏酸／腐殖质碳，降低了富里酸碳（FAC）的含量，封育草地土壤的 H AC／FAC是自由放牧草地土壤的5．66倍。此外，长期封育草地土壤的脂族碳含量显著增加，芳香度相应增加，疏水碳／亲水碳增大。总之，长期封育不仅提高了草地土壤有机碳贮量，还能改善草地土壤结构、增强土壤有机碳的稳定性。展开更多
Ploughing and fertilization practices in rice-wheat system have deteriorated the soil carbon (C) pools. Conservation agriculture (CA) based management approaches have proven to enhance C sequestration and reverse the ...Ploughing and fertilization practices in rice-wheat system have deteriorated the soil carbon (C) pools. Conservation agriculture (CA) based management approaches have proven to enhance C sequestration and reverse the loss of soil-organic-carbon (SOC), which further enhances soil fertility. Different fractions of SOC pools react to the alterations in management practices and indicate changes in SOC dynamics as compared to total C in the soil. Higher SOC levels in soil have been observed in case of reduced/no-till (NT) practices than conventional tillage (CT). However, between CT and zero tillage/NT, total SOC stocks diminished with an increase in soil depth, which demonstrated that the benefits of SOC are more pronounced in the topsoil under NT. Soil aggregation provides physical protection to C associated with different-sized particles, thus, the improvement in soil aggregation through CA is an effective way to mitigate soil C loss. Along with less soil disturbance, residual management, suitable crop rotation, rational application of manures and fertilizers, and integrated nutrient management have been found to be effective in not only improving soil C stock but also enhancing the soil health and productivity. Thus, CA can be considered as a potential method in the build-up of SOC of soil in rice-wheat system.展开更多
Soil chemistry influences plant health and carbon storage in forest ecosystems. Increasing nitrogen(N) deposition has potential effect on soil chemistry. We studied N deposition effects on soil chemistry in subtropica...Soil chemistry influences plant health and carbon storage in forest ecosystems. Increasing nitrogen(N) deposition has potential effect on soil chemistry. We studied N deposition effects on soil chemistry in subtropical Pleioblastus amarus bamboo forest ecosystems. An experiment with four N treatment levels(0, 50, 150,and300 kg N ha-1a-1,applied monthly, expressed as CK,LN,MN, HN,respectively) in three replicates. After6 years of N additions, soil base cations, acid-forming cations, exchangeable acidity(EA), organic carbon fractions and nitrogen components were measured in all four seasons. The mean soil pH values in CK,LN,MN and HN were 4.71, 4.62, 4.71, and 4.40, respectively, with a significant difference between CK and HN. Nitrogen additions significantly increased soil exchangeable Al3+,EA, and Al/Ca,and exchangeable Al3+ in HN increased by 70%compared to CK. Soil base cations(Ca2+, Mg2+, K+, and Na+) did not respond to N additions. Nitrogen treatments significantly increased soil NO3--N but had little effect on soil total nitrogen, particulate organic nitrogen, or NH4~+-N. Nitrogen additions did not affect soil total organic carbon, extractable dissolved organic carbon,incorporated organic carbon, or particulate organic carbon.This study suggests that increasing N deposition could increase soil NO3--N, reduce soil pH, and increase mobilization of Al3+. These changes induced by N deposition can impede root grow and function, further may influence soil carbon storage and nutrient cycles in the future.展开更多
Background: Soil organic carbon(SOC) is a large reservoir of terrestrial carbon(C); it consists of different fractions of varying complexity and stability. Partitioning SOC into different pools of decomposability help...Background: Soil organic carbon(SOC) is a large reservoir of terrestrial carbon(C); it consists of different fractions of varying complexity and stability. Partitioning SOC into different pools of decomposability help better predict the trend of changes in SOC dynamics under climate change. Information on how physical fractions and chemical structures of SOC are related to climate and vegetation types is essential for spatial model ing of SOC processes and responses to global change factors.Method: Soil samples were col ected from multiple representative forest sites of three contrasting climatic zones(i.e. cool temperate, warm temperate, and subtropical) in eastern China. Measurements were made on SOC contents and physical fractions of the 0–20 cm soil layer, and the chemical composition of SOC of the 0–5 cm soil layer, along with measurements and compilation of the basic site and forest stand variables. The long-term effects of temperature, litter inputs, soil characteristics and vegetation type on the SOC contents and factions were examined by means of "space for time substitution" approach and statistical analysis.Result: Mean annual temperature(MAT) varied from 2.1 °C at the cool temperate sites to 20.8 °C at the subtropical sites. Total SOC of the 0–20 cm soil layer decreased with increasing MAT, ranging from 89.2 g·kg^(-1) in cool temperate forests to 57.7 g·kg^(-1) in subtropical forests, at an average rate of 1.87% reduction in SOC with a 1 °C increase in MAT.With increasing MAT, the proportions of aromatic C and phenolic C displayed a tendency of decreases, whereas the proportion of alkyl C and A/O-A value(the ratio of alkyl C to the sum of O-alkyl C and acetal C) displayed a tendency of increases. Overall, there were no significant changes with MAT and forest type in either the physical fractions or the chemical composition. Based on the relationship between the SOC content and MAT, we estimate that SOC in the top 20 soil layer of forests potentially contribute 6.58–26.3 Pg C globally to t展开更多
为了研究成都市区内各级铺装道路积尘中碳组分特征,于2014年4~6月采集了成都市各类道路路面积尘,并利用DRI Model 2001A热光碳分析仪测定样品碳组分含量,AP-42模型计算碳排放因子。结果显示:成都市铺装道路积尘中OC浓度支路(64.28±...为了研究成都市区内各级铺装道路积尘中碳组分特征,于2014年4~6月采集了成都市各类道路路面积尘,并利用DRI Model 2001A热光碳分析仪测定样品碳组分含量,AP-42模型计算碳排放因子。结果显示:成都市铺装道路积尘中OC浓度支路(64.28±30.59mg/g)>次干路(49.25±20.28mg/g)>主干路(35.32±14.95mg/g),EC浓度支路(19.06±10.66mg/g)>次干路(17.16±7.81mg/g)>主干路(13.37±6.25mg/g);碳排放因子支路>次干路>主干路;支路沥青路面积尘的碳组分浓度高于水泥路面,排放因子低于水泥路面;来源解析结果显示,成都市铺装道路碳主要来源于汽油车排放和柴油车排放。展开更多
文摘封育是当前恢复和改良内蒙古草地的重要措施，也是实现草地固碳效应最有效的途径之一。本文利用内蒙古封育32年和自由放牧的羊草草地，分析了其土壤有机碳组分、土壤团聚体和土壤腐殖质组分碳含量的变化，并运用13 C核磁共振波普法对土壤腐殖质的有机碳组分进行波普分析，探讨了长期封育对羊草草地土壤有机碳组分和土壤有机质结构的影响，期望能为科学地评估长期封育状况下草地固碳效应及其稳定性提供理论依据。实验结果表明：长期封育显著提高了草地土壤有机碳含量；在土壤有机碳组分中，除土壤微生物碳（MBC ）含量降低外，其碳组分含量都相应增加。其中，易氧化有机碳（EOC）含量增加最为明显，长期封育草地是自由放牧草地土壤的4．53倍；长期封育显著提高了草地土壤0．25～2 mm 团聚体所占比例及其有机碳含量；长期封育提高了草地土壤腐殖质中的胡敏酸碳（HAC）、胡敏素碳（HUC）含量和胡敏酸／腐殖质碳，降低了富里酸碳（FAC）的含量，封育草地土壤的 H AC／FAC是自由放牧草地土壤的5．66倍。此外，长期封育草地土壤的脂族碳含量显著增加，芳香度相应增加，疏水碳／亲水碳增大。总之，长期封育不仅提高了草地土壤有机碳贮量，还能改善草地土壤结构、增强土壤有机碳的稳定性。
文摘Ploughing and fertilization practices in rice-wheat system have deteriorated the soil carbon (C) pools. Conservation agriculture (CA) based management approaches have proven to enhance C sequestration and reverse the loss of soil-organic-carbon (SOC), which further enhances soil fertility. Different fractions of SOC pools react to the alterations in management practices and indicate changes in SOC dynamics as compared to total C in the soil. Higher SOC levels in soil have been observed in case of reduced/no-till (NT) practices than conventional tillage (CT). However, between CT and zero tillage/NT, total SOC stocks diminished with an increase in soil depth, which demonstrated that the benefits of SOC are more pronounced in the topsoil under NT. Soil aggregation provides physical protection to C associated with different-sized particles, thus, the improvement in soil aggregation through CA is an effective way to mitigate soil C loss. Along with less soil disturbance, residual management, suitable crop rotation, rational application of manures and fertilizers, and integrated nutrient management have been found to be effective in not only improving soil C stock but also enhancing the soil health and productivity. Thus, CA can be considered as a potential method in the build-up of SOC of soil in rice-wheat system.
基金financially supported by the Openend Fund of Ecological Security and Protection Key Laboratory of Sichuan ProvinceMianyang Normal University(ESP1507)the National Natural Science Foundation of China(31300522)
文摘Soil chemistry influences plant health and carbon storage in forest ecosystems. Increasing nitrogen(N) deposition has potential effect on soil chemistry. We studied N deposition effects on soil chemistry in subtropical Pleioblastus amarus bamboo forest ecosystems. An experiment with four N treatment levels(0, 50, 150,and300 kg N ha-1a-1,applied monthly, expressed as CK,LN,MN, HN,respectively) in three replicates. After6 years of N additions, soil base cations, acid-forming cations, exchangeable acidity(EA), organic carbon fractions and nitrogen components were measured in all four seasons. The mean soil pH values in CK,LN,MN and HN were 4.71, 4.62, 4.71, and 4.40, respectively, with a significant difference between CK and HN. Nitrogen additions significantly increased soil exchangeable Al3+,EA, and Al/Ca,and exchangeable Al3+ in HN increased by 70%compared to CK. Soil base cations(Ca2+, Mg2+, K+, and Na+) did not respond to N additions. Nitrogen treatments significantly increased soil NO3--N but had little effect on soil total nitrogen, particulate organic nitrogen, or NH4~+-N. Nitrogen additions did not affect soil total organic carbon, extractable dissolved organic carbon,incorporated organic carbon, or particulate organic carbon.This study suggests that increasing N deposition could increase soil NO3--N, reduce soil pH, and increase mobilization of Al3+. These changes induced by N deposition can impede root grow and function, further may influence soil carbon storage and nutrient cycles in the future.
基金supported by the National Natural Science Foundation of China(Grant No.31470623)the National Basic Research Program of China(Grant No.2011CB403205)
文摘Background: Soil organic carbon(SOC) is a large reservoir of terrestrial carbon(C); it consists of different fractions of varying complexity and stability. Partitioning SOC into different pools of decomposability help better predict the trend of changes in SOC dynamics under climate change. Information on how physical fractions and chemical structures of SOC are related to climate and vegetation types is essential for spatial model ing of SOC processes and responses to global change factors.Method: Soil samples were col ected from multiple representative forest sites of three contrasting climatic zones(i.e. cool temperate, warm temperate, and subtropical) in eastern China. Measurements were made on SOC contents and physical fractions of the 0–20 cm soil layer, and the chemical composition of SOC of the 0–5 cm soil layer, along with measurements and compilation of the basic site and forest stand variables. The long-term effects of temperature, litter inputs, soil characteristics and vegetation type on the SOC contents and factions were examined by means of "space for time substitution" approach and statistical analysis.Result: Mean annual temperature(MAT) varied from 2.1 °C at the cool temperate sites to 20.8 °C at the subtropical sites. Total SOC of the 0–20 cm soil layer decreased with increasing MAT, ranging from 89.2 g·kg^(-1) in cool temperate forests to 57.7 g·kg^(-1) in subtropical forests, at an average rate of 1.87% reduction in SOC with a 1 °C increase in MAT.With increasing MAT, the proportions of aromatic C and phenolic C displayed a tendency of decreases, whereas the proportion of alkyl C and A/O-A value(the ratio of alkyl C to the sum of O-alkyl C and acetal C) displayed a tendency of increases. Overall, there were no significant changes with MAT and forest type in either the physical fractions or the chemical composition. Based on the relationship between the SOC content and MAT, we estimate that SOC in the top 20 soil layer of forests potentially contribute 6.58–26.3 Pg C globally to t
文摘为了研究成都市区内各级铺装道路积尘中碳组分特征,于2014年4~6月采集了成都市各类道路路面积尘,并利用DRI Model 2001A热光碳分析仪测定样品碳组分含量,AP-42模型计算碳排放因子。结果显示:成都市铺装道路积尘中OC浓度支路(64.28±30.59mg/g)>次干路(49.25±20.28mg/g)>主干路(35.32±14.95mg/g),EC浓度支路(19.06±10.66mg/g)>次干路(17.16±7.81mg/g)>主干路(13.37±6.25mg/g);碳排放因子支路>次干路>主干路;支路沥青路面积尘的碳组分浓度高于水泥路面,排放因子低于水泥路面;来源解析结果显示,成都市铺装道路碳主要来源于汽油车排放和柴油车排放。
