本研究基于华北平原区的少耕培肥长期定位试验(1985年至今),以冬小麦--夏玉米轮作体系为研究对象,研究了长期施用氮磷肥、不同耕作方式结合秸秆还田对土壤过氧化氢酶活性的影响。结果表明:土壤过氧化氢酶活性与土壤温度的相关性极显著,...本研究基于华北平原区的少耕培肥长期定位试验(1985年至今),以冬小麦--夏玉米轮作体系为研究对象,研究了长期施用氮磷肥、不同耕作方式结合秸秆还田对土壤过氧化氢酶活性的影响。结果表明:土壤过氧化氢酶活性与土壤温度的相关性极显著,冬小麦和夏玉米生长季两者间的相关系数分别为:0.738**和0.907**,说明在一定范围内温度增强了酶与底物的亲和力、提高了酶的活性。土壤酶的活性与施肥等因素有一定的相关性:氮肥施用量对土壤过氧化氢酶的活性影响不大(P>0.05);无论是小麦季还是玉米季,随着磷肥施用量的增加,土壤过氧化氢酶的活性呈现明显的下降趋势,说明施用磷肥明显抑制了土壤过氧化氢酶的活性(P<0.05);随着秸秆还田量的增加,土壤过氧化氢酶的活性表现出了增加的趋势,但效果不显著(P>0.05)。不同耕作方式对土壤过氧化氢酶活性的影响不显著(P>0.05)。总之,在少耕条件下,不施用磷肥、少施用氮肥(225 kg N hm^-2a^-1)和高量秸秆(4500 kg hm^-2a^-1)的处理有利于提高过氧化氢酶的活性。展开更多
Developments in soil biology and in methodsto characterize soil organic carbon can potentially delivernovel soil quality indicators that can help identifymanagement practices able to sustain soil productivityand envir...Developments in soil biology and in methodsto characterize soil organic carbon can potentially delivernovel soil quality indicators that can help identifymanagement practices able to sustain soil productivityand environmental resilience. This work aimed atsynthesizing results regarding the suitability of a range ofsoil biological and biochemical properties as novel soilquality indicators for agricultural management. The soilproperties, selected through a published literature review,comprised different labile organic carbon fractions [hydrophilicdissolved organic carbon, dissolved organic carbon,permanganate oxidizable carbon (POXC), hot waterextractable carbon and particulate organic matter carbon],soil disease suppressiveness measured using a Pythium-Lepidium bioassay, nematode communities characterizedby amplicon sequencing and qPCR, and microbialcommunity level physiological profiling measured withMicroResp™. Prior studies tested the sensitivity of each ofthe novel indicators to tillage and organic matter additionin ten European long-term field experiments (LTEs) andassessed their relationships with pre-existing soil qualityindicators of soil functioning. Here, the results of theseprevious studies are brought together and interpretedrelative to each other and to the broader body of literatureon soil quality assessment. Reduced tillage increasedcarbon availability, disease suppressiveness, nematoderichness and diversity, the stability and maturity of thefood web, and microbial activity and functional diversity.Organic matter addition played a weaker role in enhancingsoil quality, possibly due to the range of composition of theorganic matter inputs used in the LTEs. POXC was theindicator that discriminated best between soil managementpractices, followed by nematode indices based on functionalcharacteristics. Structural equation modeling showsthat POXC has a central role in nutrient retention/supply,carbon sequestration, biodiversity conservation, erosion control and disease regulation/suppression. The novelind展开更多
To ascertain the effects of long-term conservation tillage and residue retention on soil organic carbon(SOC) content and aggregate distribution in a deep soil(>20-cm depth) in a dryland environment,this paper analy...To ascertain the effects of long-term conservation tillage and residue retention on soil organic carbon(SOC) content and aggregate distribution in a deep soil(>20-cm depth) in a dryland environment,this paper analyzed the SOC and aggregate distribution in soil, and the aggregate-associated organic carbon(OC) and SOC physical fractions. Conservation tillage(reduced tillage with residue incorporated(RT) and no-tillage with residue mulch(NT)) significantly increased SOC sequestration and soil aggregation in deep soil compared with conventional tillage with residue removal(CT). Compared with CT, RT significantly increased the proportion of small macroaggregates by 23%–81% in the 10–80 cm layer, and the OC content in small macroaggregates by 1%–58% in the 0–80 cm layer. RT significantly increased(by 24%–90%) the OC content in mineral-SOC within small macroaggregates in the 0–60 cm layer, while there was a 23%–80% increase in the 0–40 cm layer with NT. These results indicated that:(1) conservation tillage treatments are beneficial for soil aggregation and SOC sequestration in a deep soil in a dryland environment; and(2)the SOC in mineral-associated OC plays important roles in soil aggregation and SOC sequestration. In conclusion, RT with NT is recommended as an agricultural management tool in dryland soils because of its role in improving soil aggregation and SOC sequestration.展开更多
Long-term experiments can be used to assess management induced changes in soil properties and sustainability of the management system in terms of the productivity. Such data are scanty, especially in the semi-arid tro...Long-term experiments can be used to assess management induced changes in soil properties and sustainability of the management system in terms of the productivity. Such data are scanty, especially in the semi-arid tropics (SAT) region. A long-term experiment established in 1976 at ICRISAT in India on Vertisols with two management treatments;improved management (IM), comprising semi-permanent broadbed and furrow (BBF) landform with minimum tillage and improved cropping practices;and traditional management (TM) system comprising keeping the land fallow during the rainy season and sowing on flat landform during post-rainy season with traditional cropping practices, was sampled after 24 and 34 years for soil physical and hydrological properties. Results showed that both in short-and long-term the management systems had profound effect on crop yields. Also in the long-term IM and TM management systems had significant effect on several soil physical and hydrological properties. Throughout the soil profile IM systems had significantly lower bulk density, significantly higher porosity, substantially lower penetration resistance both at 5 cm (1 and 8 MPa) and 15 cm depths (8 and 15 MPa), significantly higher infiltration and sorptivity and significantly larger mean weight diameter of 4.3 mm compared to 2.8 mm for soils under TM. However, management systems had no significant effect on moisture holding capacities both at 0.033 and 1.5 MPa. Significant differences between the improved and traditional systems were observed in the size and pattern of soil surface cracks. Over the long-term, the improved management systems has very favorable effects on soil physical and hydrological properties and on the soil surface cracking and its patterns, thereby contributing to higher productivity.展开更多
Biochar application and conservation tillage are significant for long-term organic carbon(OC)sequestration in soil and enhancing crop yields,however,their effects on native soil organic carbon(native SOC)without bioch...Biochar application and conservation tillage are significant for long-term organic carbon(OC)sequestration in soil and enhancing crop yields,however,their effects on native soil organic carbon(native SOC)without biochar carbon sequestration in situ remain largely unknown.Here,an 11-year field experiment was carried out to examine different biochar application rates(0,30,60,and 90 Mg ha^(−1))on native SOC pools(native labile SOC pool I and II,and native recalcitrant SOC)and microbial activities in calcareous soil across an entire winter wheat-maize rotation.The proportions of C_(3) and C_(4)-derived native SOC mineralization were quantified using soil basal respiration(SBR)combined with 13C natural isotope abundance measurements.The results showed that 39-51%of the biochar remained in the top 30 cm after 11 years.Biochar application rates significantly increased native SOC and native recalcitrant SOC contents but decreased the proportion of native labile SOC[native labile SOC pool I and II,dissolved organic carbon(DOC),and microbial biomass carbon(MBC)].Biochar application tended to increase the indicators of microbial activities associated with SOC degradation,such as SBR,fluorescein diacetate hydrolysis activity,and metabolic quotient(qCO_(2)).Meanwhile,higher biochar application rates(B60 and B90)significantly increased the C_(4)-derived CO_(2) proportion of the SBR and enhanced C_(4)-derived native SOC mineralization.The effect of the biochar application rate on the content and proportion of native SOC fractions occurred in the 0-15 cm layer,however,there were no significant differences at 15-30 cm.Soil depth also significantly increased native labile SOC pool Ⅰ and Ⅱ contents and decreased qCO_(2).In conclusion,the biochar application rate significantly increased native SOC accumulation in calcareous soil by enhancing the proportion of native recalcitrant SOC,and biochar application and soil depth collectively influenced the seasonal turnover of native SOC fractions,which has important implications for 展开更多
文摘本研究基于华北平原区的少耕培肥长期定位试验(1985年至今),以冬小麦--夏玉米轮作体系为研究对象,研究了长期施用氮磷肥、不同耕作方式结合秸秆还田对土壤过氧化氢酶活性的影响。结果表明:土壤过氧化氢酶活性与土壤温度的相关性极显著,冬小麦和夏玉米生长季两者间的相关系数分别为:0.738**和0.907**,说明在一定范围内温度增强了酶与底物的亲和力、提高了酶的活性。土壤酶的活性与施肥等因素有一定的相关性:氮肥施用量对土壤过氧化氢酶的活性影响不大(P>0.05);无论是小麦季还是玉米季,随着磷肥施用量的增加,土壤过氧化氢酶的活性呈现明显的下降趋势,说明施用磷肥明显抑制了土壤过氧化氢酶的活性(P<0.05);随着秸秆还田量的增加,土壤过氧化氢酶的活性表现出了增加的趋势,但效果不显著(P>0.05)。不同耕作方式对土壤过氧化氢酶活性的影响不显著(P>0.05)。总之,在少耕条件下,不施用磷肥、少施用氮肥(225 kg N hm^-2a^-1)和高量秸秆(4500 kg hm^-2a^-1)的处理有利于提高过氧化氢酶的活性。
基金the EU Horizon 2020 projectInteractive Soil Quality Assessment in Europe and China for agriculturalproductivity and environmental resilience (iSQAPER), grant number 635750(mediated through the Swiss State Secretariat for Education, Research andInnovation). The University of Ljubljana, University of Trier, UniversityMiguel Hernandez, and the long-term field experiment owners providedsamples and data, and Lijbert Brussaard, Ron de Goede, Else Biinemann-Konig and Paul Mader provided constructive feedback on earlier versions ofthe manuscript.
文摘Developments in soil biology and in methodsto characterize soil organic carbon can potentially delivernovel soil quality indicators that can help identifymanagement practices able to sustain soil productivityand environmental resilience. This work aimed atsynthesizing results regarding the suitability of a range ofsoil biological and biochemical properties as novel soilquality indicators for agricultural management. The soilproperties, selected through a published literature review,comprised different labile organic carbon fractions [hydrophilicdissolved organic carbon, dissolved organic carbon,permanganate oxidizable carbon (POXC), hot waterextractable carbon and particulate organic matter carbon],soil disease suppressiveness measured using a Pythium-Lepidium bioassay, nematode communities characterizedby amplicon sequencing and qPCR, and microbialcommunity level physiological profiling measured withMicroResp™. Prior studies tested the sensitivity of each ofthe novel indicators to tillage and organic matter additionin ten European long-term field experiments (LTEs) andassessed their relationships with pre-existing soil qualityindicators of soil functioning. Here, the results of theseprevious studies are brought together and interpretedrelative to each other and to the broader body of literatureon soil quality assessment. Reduced tillage increasedcarbon availability, disease suppressiveness, nematoderichness and diversity, the stability and maturity of thefood web, and microbial activity and functional diversity.Organic matter addition played a weaker role in enhancingsoil quality, possibly due to the range of composition of theorganic matter inputs used in the LTEs. POXC was theindicator that discriminated best between soil managementpractices, followed by nematode indices based on functionalcharacteristics. Structural equation modeling showsthat POXC has a central role in nutrient retention/supply,carbon sequestration, biodiversity conservation, erosion control and disease regulation/suppression. The novelind
基金supported jointly by the National Key Research and Development Program of China (2018YFD0200408, 2016YFD0300804)the Science and Technology Project (2015BAD22B03)the Basic Scientific Research Business Expenses of the Chinese Academy of Agricultural Sciences (1610132018024)
文摘To ascertain the effects of long-term conservation tillage and residue retention on soil organic carbon(SOC) content and aggregate distribution in a deep soil(>20-cm depth) in a dryland environment,this paper analyzed the SOC and aggregate distribution in soil, and the aggregate-associated organic carbon(OC) and SOC physical fractions. Conservation tillage(reduced tillage with residue incorporated(RT) and no-tillage with residue mulch(NT)) significantly increased SOC sequestration and soil aggregation in deep soil compared with conventional tillage with residue removal(CT). Compared with CT, RT significantly increased the proportion of small macroaggregates by 23%–81% in the 10–80 cm layer, and the OC content in small macroaggregates by 1%–58% in the 0–80 cm layer. RT significantly increased(by 24%–90%) the OC content in mineral-SOC within small macroaggregates in the 0–60 cm layer, while there was a 23%–80% increase in the 0–40 cm layer with NT. These results indicated that:(1) conservation tillage treatments are beneficial for soil aggregation and SOC sequestration in a deep soil in a dryland environment; and(2)the SOC in mineral-associated OC plays important roles in soil aggregation and SOC sequestration. In conclusion, RT with NT is recommended as an agricultural management tool in dryland soils because of its role in improving soil aggregation and SOC sequestration.
文摘Long-term experiments can be used to assess management induced changes in soil properties and sustainability of the management system in terms of the productivity. Such data are scanty, especially in the semi-arid tropics (SAT) region. A long-term experiment established in 1976 at ICRISAT in India on Vertisols with two management treatments;improved management (IM), comprising semi-permanent broadbed and furrow (BBF) landform with minimum tillage and improved cropping practices;and traditional management (TM) system comprising keeping the land fallow during the rainy season and sowing on flat landform during post-rainy season with traditional cropping practices, was sampled after 24 and 34 years for soil physical and hydrological properties. Results showed that both in short-and long-term the management systems had profound effect on crop yields. Also in the long-term IM and TM management systems had significant effect on several soil physical and hydrological properties. Throughout the soil profile IM systems had significantly lower bulk density, significantly higher porosity, substantially lower penetration resistance both at 5 cm (1 and 8 MPa) and 15 cm depths (8 and 15 MPa), significantly higher infiltration and sorptivity and significantly larger mean weight diameter of 4.3 mm compared to 2.8 mm for soils under TM. However, management systems had no significant effect on moisture holding capacities both at 0.033 and 1.5 MPa. Significant differences between the improved and traditional systems were observed in the size and pattern of soil surface cracks. Over the long-term, the improved management systems has very favorable effects on soil physical and hydrological properties and on the soil surface cracking and its patterns, thereby contributing to higher productivity.
基金This research received funding from the National Natural Science Foundation of China(No.61511012).
文摘Biochar application and conservation tillage are significant for long-term organic carbon(OC)sequestration in soil and enhancing crop yields,however,their effects on native soil organic carbon(native SOC)without biochar carbon sequestration in situ remain largely unknown.Here,an 11-year field experiment was carried out to examine different biochar application rates(0,30,60,and 90 Mg ha^(−1))on native SOC pools(native labile SOC pool I and II,and native recalcitrant SOC)and microbial activities in calcareous soil across an entire winter wheat-maize rotation.The proportions of C_(3) and C_(4)-derived native SOC mineralization were quantified using soil basal respiration(SBR)combined with 13C natural isotope abundance measurements.The results showed that 39-51%of the biochar remained in the top 30 cm after 11 years.Biochar application rates significantly increased native SOC and native recalcitrant SOC contents but decreased the proportion of native labile SOC[native labile SOC pool I and II,dissolved organic carbon(DOC),and microbial biomass carbon(MBC)].Biochar application tended to increase the indicators of microbial activities associated with SOC degradation,such as SBR,fluorescein diacetate hydrolysis activity,and metabolic quotient(qCO_(2)).Meanwhile,higher biochar application rates(B60 and B90)significantly increased the C_(4)-derived CO_(2) proportion of the SBR and enhanced C_(4)-derived native SOC mineralization.The effect of the biochar application rate on the content and proportion of native SOC fractions occurred in the 0-15 cm layer,however,there were no significant differences at 15-30 cm.Soil depth also significantly increased native labile SOC pool Ⅰ and Ⅱ contents and decreased qCO_(2).In conclusion,the biochar application rate significantly increased native SOC accumulation in calcareous soil by enhancing the proportion of native recalcitrant SOC,and biochar application and soil depth collectively influenced the seasonal turnover of native SOC fractions,which has important implications for
