Agricultural liming contributes significantly to atmospheric CO2 emission from soils but data on magnitude of lime- contributed CO2 in a wide range of acid soils are still few. Data on lime-contributed CO2 and SOC tur...Agricultural liming contributes significantly to atmospheric CO2 emission from soils but data on magnitude of lime- contributed CO2 in a wide range of acid soils are still few. Data on lime-contributed CO2 and SOC turnover for global acid soils are needed to estimate the potential contribution of agricultural liming to atmospheric CO2. Using Ca13CO3 (13C 99%) as lime and tracer, here we separated lime-contributed and SOC-originated CO2 evolution in an acidic Kuroboku Andisol from Tanashi, Tokyo Prefecture (35°44′ N, 139°32′ E) and Kunigami Mahji Ultisol of Nakijin, Okinawa Prefecture, Japan (26°38′ N, 127°58′ E). On the average, lime-CO2 was 76.84% (Kuroboku Andisol) and 66.36% (Kunigami Mahji Ultisol) of overall CO2 emission after 36 days. There was increased SOC turnover in all limed soils, confirming priming effect (PE) of liming. The calculated PE of lime (Kuroboku Andisol, 51.97% - 114.95%;Kunigami Mahji Ultisol, 10.13% - 35.61%) was entirely 12C turnover of stable soil organic carbon (SOC) since SMBC, a labile SOC pool, was suppressed by liming in our experiment. Our results confirmed that mineralization of lime-carbonates is the major source of CO2 emission from acid soils during agricultural liming. Liming can influence the size of CO2 evolution from agricultural ecosystems considering global extent of acid soils and current volume of lime utilization. We propose the inclusion of liming in simulating carbon dynamics in agricultural ecosystems.展开更多
We characterized humic acids （HAs） and glycerol-extractable organic fractions （GEOFs） extracted from four Andisols, taken from comparable soil-climate conditions on the east side of Mount Etna. The soils were form...We characterized humic acids （HAs） and glycerol-extractable organic fractions （GEOFs） extracted from four Andisols, taken from comparable soil-climate conditions on the east side of Mount Etna. The soils were formed on old lava （about 9000 years ago）, old tephra （about 8 700 years ago）, recent lava （about 2 600 years ago） and recent tephra （about 3600 years ago）. A part of the organic matter of the soils, deprived of HAs and fulvic acids （FAs）, was isolated by glycerol extraction. The GEOF can not be extracted with alkaline solutions, probably because it is closely bound to the mineral component of the soil. The characterization of the extracted organic fraction was carried out using elementary and functional group analysis and Fourier transform infrared （FT-IR） spectroscopy. About 20 extractions were necessary to extract the HA and FA from the older soils and about 10 extractions to extract them from the younger soils. Data showed that the CEOFs had a greater ash content and a smaller N content, as well as a greater presence of aliphatic compounds and carboxylic groups as compared to the HA extracted from the same soil. The GEOFs extracted from younger soils also had a lower yield, ash and COOH-group content, and were more aliphatic than the GEOF extracted from older soils. Finally, the GEOFs were more closely bound to the amorphous component of the soil （＇short-range＇ minerals） and consequently less subject to biodegradation.展开更多
Economic losses associated with grass tetany either of death or poor growth performance of livestock are a growing concern. Breeding of high magnesium (high-Mg) cool-season forage grass (C<sub>3</sub>) has...Economic losses associated with grass tetany either of death or poor growth performance of livestock are a growing concern. Breeding of high magnesium (high-Mg) cool-season forage grass (C<sub>3</sub>) has been a challenging process to minimize the hazards of grass tetany. For appraising the breeding of high Mg-containing cultivars in Japanese Andisol, agronomic properties and grass tetany risk of high-Mg cultivars were compared with commercial cultivars. The high-Mg cultivars of Italian ryegrass (Lolium multiflorum L.), tall fescue (Festuca arundinacea Schreb.), and orchardgrass (Dactylis glomerata L.) were “Magnet”, “HiMag” and “Mgwell”, respectively. The commercial cultivars were viz., Ace, Tachiwase, and Waseyutaka of Italian ryegrass, Hokuryo, Kentucky-31 (Ky-31), and Fawn of tall fescue, and Akimidori and Okamidori of orchardgrass, respectively. Grasses were grown in temperate Andisol under field conditions with standard management practices and were harvested four times during the year. The average plant heights of the high-Mg containing cultivars were lower than the commercial cultivars with the relative range of −7.4%, −3.7%, and −1.5% for Italian ryegrass, tall fescue, and orchard grass species, respectively. The seasonal yield of high-Mg cultivars was ranked as Magnet > HiMag > Mgwell. The Mgwell orchard grass had lower potassium (K) content compared with their respective commercial cultivars with a relative range of −2.2%. Across four harvests, a significantly higher calcium (Ca) and magnesium (Mg) content, and lower grass tetany potential were recorded in high-Mg cultivars when compared to commercial cultivars, irrespective of species. Across four harvests, the lowest grass tetany index, [K/(Ca + Mg)] of 1.36 was recorded in Mgwell orchard grass. The high-Mg cultivars showed the lowest [K/(Ca + Mg)] across four harvests compared to commercial cultivars, promoting the effectiveness of breeding cool-season grass species to control grass tetany in temperate regions (Andisol) and climatic conditions.展开更多
《中国土壤系统分类检索》(第三版,CST)关于火山灰土的诊断标准还存在一定问题,需要进一步修订。为此,整理并比较了《世界土壤资源参比基础》(World Reference Base for Soil Resources,WRB,1998—2014版)、美国《土壤系统分类检索》(Ke...《中国土壤系统分类检索》(第三版,CST)关于火山灰土的诊断标准还存在一定问题,需要进一步修订。为此,整理并比较了《世界土壤资源参比基础》(World Reference Base for Soil Resources,WRB,1998—2014版)、美国《土壤系统分类检索》(Keys to Soil Taxonomy,KST)(第3~12版,1987—2012年)、《中国土壤系统分类检索》(首次方案至第三版,1991—2001年)中,关于火山灰土的描述、诊断标准、分类检索和类型划分的演变历程,在此基础上提出了CST关于火山灰土诊断标准和分类检索的修订建议。展开更多
Aims We tested whether—in addition to weather conditions—the concentrations of nitrogen and phosphorus in the substrate have an effect on the radial stem increment of Nothofagus dombeyi trees in old-growth forest st...Aims We tested whether—in addition to weather conditions—the concentrations of nitrogen and phosphorus in the substrate have an effect on the radial stem increment of Nothofagus dombeyi trees in old-growth forest stands on volcanic soil at the western slopes of the Andes in South-Central Chile.Methods We took soil samples and tree increment cores from five proximate sites(1000-1300 m a.s.l.)that are located in the volcanic region of the Conguillío National Park and differ in the age of the substrate(Miocene—3500 years B.P.)and in its concentrations of nitrogen(N)and phosphorus(P).The soil samples were also analysed on their concentrations of other plant mineral nutrients,carbon(C)and nitrogen isotope ratios(δ^(15)N).Tree-ring widths and the stem basal area increment(BAI)were related to climate parameters.In selected tree rings,the stable isotope ratios of carbon(δ^(13)C)and oxygen(δ^(18)O)were determined and related to growth and climate parameters.Important FindingsConsistent with theory,the soils on the oldest substrate showed the highest(least negative)δ^(15)N values,but mineral N was the only nutrient whose concentration exhibited a straightforward(increasing)relationship with increasing substrate age.The BAI was largest on the soil with the highest concentration of plant-available P.In contrast to BAI,tree-ring chronologies did not differ among the study sites.However,tree-ring chronologies and BAI exhibited significantly positive correlations with summer precipitation,and negative correlations,with summer(December)temperature.A negative correlation was found betweenδ^(13)C and precipitation anomalies in the growing season(November-March).We interpret the negative correlations between growth and temperature,and betweenδ^(13)C andδ^(18)O in the tree rings,as an impairment of net carbon assimilation by anomalously warm weather conditions during the growing season.We conclude that the growth of N.dombeyi is mainly affected by high temperature and low precipitation in spring and summer irrespective of the substrate’s age,and enhanced by higher concentrations of plant-available P in the soil.Our results may be representative of N.dombeyi stands on volcanic substrate within their principal distribution range along the Andes of South America.展开更多
Many Hawaiian agricultural soils are acidic with low-nutrient retention;therefore,organic soil amendments are often used to improve soil properties and increase yields.Amendments can be incorporated for annual crops,b...Many Hawaiian agricultural soils are acidic with low-nutrient retention;therefore,organic soil amendments are often used to improve soil properties and increase yields.Amendments can be incorporated for annual crops,but perennial orchards need surface application to avoid damaging surface roots.Pot trials compared responses to incorporated(IBC)or surface-applied(SBC)combination of hardwood biochar and chicken manure compost(4%v/v of each amendment)added to an Andisol and Oxisol.Soil pH was increased by 0.4-1.1 units in IBC and by 0.2-0.5 for SBC in the 0-10 cm soil layer.Both SBC and IBC increased soil total N,extractable P,Ca and Mg in the 0-10 cm soil layer.Soil pH,total C and extractable Ca were also higher in the 10-20 cm soil layer for IBC soil,indicating movement and/or leaching of amendments.Chinese cabbage biomass was 18-70%higher in the IBC and 14-47%higher in the SBC than that in the unamended soil,while papaya biomass was 23%and 19%higher in SBC and IBC,respectively.There was a greater response in the more acidic Andisol soil,with larger improvements in soil pH,plant nutrient uptake and root biomass than the Oxisol.Surface application was as effective in increasing plant growth as the incorporated amendment,providing evidence for farm scale assessment.Biochar and compost are recommended for use in tropical soils,and surface application may be beneficial to annual and perennial crops.展开更多
文摘Agricultural liming contributes significantly to atmospheric CO2 emission from soils but data on magnitude of lime- contributed CO2 in a wide range of acid soils are still few. Data on lime-contributed CO2 and SOC turnover for global acid soils are needed to estimate the potential contribution of agricultural liming to atmospheric CO2. Using Ca13CO3 (13C 99%) as lime and tracer, here we separated lime-contributed and SOC-originated CO2 evolution in an acidic Kuroboku Andisol from Tanashi, Tokyo Prefecture (35°44′ N, 139°32′ E) and Kunigami Mahji Ultisol of Nakijin, Okinawa Prefecture, Japan (26°38′ N, 127°58′ E). On the average, lime-CO2 was 76.84% (Kuroboku Andisol) and 66.36% (Kunigami Mahji Ultisol) of overall CO2 emission after 36 days. There was increased SOC turnover in all limed soils, confirming priming effect (PE) of liming. The calculated PE of lime (Kuroboku Andisol, 51.97% - 114.95%;Kunigami Mahji Ultisol, 10.13% - 35.61%) was entirely 12C turnover of stable soil organic carbon (SOC) since SMBC, a labile SOC pool, was suppressed by liming in our experiment. Our results confirmed that mineralization of lime-carbonates is the major source of CO2 emission from acid soils during agricultural liming. Liming can influence the size of CO2 evolution from agricultural ecosystems considering global extent of acid soils and current volume of lime utilization. We propose the inclusion of liming in simulating carbon dynamics in agricultural ecosystems.
基金Project supported by the Research Foundation of University of Catania, Italy (No. ORCT067410/2006)
文摘We characterized humic acids （HAs） and glycerol-extractable organic fractions （GEOFs） extracted from four Andisols, taken from comparable soil-climate conditions on the east side of Mount Etna. The soils were formed on old lava （about 9000 years ago）, old tephra （about 8 700 years ago）, recent lava （about 2 600 years ago） and recent tephra （about 3600 years ago）. A part of the organic matter of the soils, deprived of HAs and fulvic acids （FAs）, was isolated by glycerol extraction. The GEOF can not be extracted with alkaline solutions, probably because it is closely bound to the mineral component of the soil. The characterization of the extracted organic fraction was carried out using elementary and functional group analysis and Fourier transform infrared （FT-IR） spectroscopy. About 20 extractions were necessary to extract the HA and FA from the older soils and about 10 extractions to extract them from the younger soils. Data showed that the CEOFs had a greater ash content and a smaller N content, as well as a greater presence of aliphatic compounds and carboxylic groups as compared to the HA extracted from the same soil. The GEOFs extracted from younger soils also had a lower yield, ash and COOH-group content, and were more aliphatic than the GEOF extracted from older soils. Finally, the GEOFs were more closely bound to the amorphous component of the soil （＇short-range＇ minerals） and consequently less subject to biodegradation.
文摘Economic losses associated with grass tetany either of death or poor growth performance of livestock are a growing concern. Breeding of high magnesium (high-Mg) cool-season forage grass (C<sub>3</sub>) has been a challenging process to minimize the hazards of grass tetany. For appraising the breeding of high Mg-containing cultivars in Japanese Andisol, agronomic properties and grass tetany risk of high-Mg cultivars were compared with commercial cultivars. The high-Mg cultivars of Italian ryegrass (Lolium multiflorum L.), tall fescue (Festuca arundinacea Schreb.), and orchardgrass (Dactylis glomerata L.) were “Magnet”, “HiMag” and “Mgwell”, respectively. The commercial cultivars were viz., Ace, Tachiwase, and Waseyutaka of Italian ryegrass, Hokuryo, Kentucky-31 (Ky-31), and Fawn of tall fescue, and Akimidori and Okamidori of orchardgrass, respectively. Grasses were grown in temperate Andisol under field conditions with standard management practices and were harvested four times during the year. The average plant heights of the high-Mg containing cultivars were lower than the commercial cultivars with the relative range of −7.4%, −3.7%, and −1.5% for Italian ryegrass, tall fescue, and orchard grass species, respectively. The seasonal yield of high-Mg cultivars was ranked as Magnet > HiMag > Mgwell. The Mgwell orchard grass had lower potassium (K) content compared with their respective commercial cultivars with a relative range of −2.2%. Across four harvests, a significantly higher calcium (Ca) and magnesium (Mg) content, and lower grass tetany potential were recorded in high-Mg cultivars when compared to commercial cultivars, irrespective of species. Across four harvests, the lowest grass tetany index, [K/(Ca + Mg)] of 1.36 was recorded in Mgwell orchard grass. The high-Mg cultivars showed the lowest [K/(Ca + Mg)] across four harvests compared to commercial cultivars, promoting the effectiveness of breeding cool-season grass species to control grass tetany in temperate regions (Andisol) and climatic conditions.
文摘《中国土壤系统分类检索》(第三版,CST)关于火山灰土的诊断标准还存在一定问题,需要进一步修订。为此,整理并比较了《世界土壤资源参比基础》(World Reference Base for Soil Resources,WRB,1998—2014版)、美国《土壤系统分类检索》(Keys to Soil Taxonomy,KST)(第3~12版,1987—2012年)、《中国土壤系统分类检索》(首次方案至第三版,1991—2001年)中,关于火山灰土的描述、诊断标准、分类检索和类型划分的演变历程,在此基础上提出了CST关于火山灰土诊断标准和分类检索的修订建议。
基金Fondo Nacional de Desarrollo Científico y Tecnológico(Fondecyt),Chile(Fondecyt Regular 1090135).
文摘Aims We tested whether—in addition to weather conditions—the concentrations of nitrogen and phosphorus in the substrate have an effect on the radial stem increment of Nothofagus dombeyi trees in old-growth forest stands on volcanic soil at the western slopes of the Andes in South-Central Chile.Methods We took soil samples and tree increment cores from five proximate sites(1000-1300 m a.s.l.)that are located in the volcanic region of the Conguillío National Park and differ in the age of the substrate(Miocene—3500 years B.P.)and in its concentrations of nitrogen(N)and phosphorus(P).The soil samples were also analysed on their concentrations of other plant mineral nutrients,carbon(C)and nitrogen isotope ratios(δ^(15)N).Tree-ring widths and the stem basal area increment(BAI)were related to climate parameters.In selected tree rings,the stable isotope ratios of carbon(δ^(13)C)and oxygen(δ^(18)O)were determined and related to growth and climate parameters.Important FindingsConsistent with theory,the soils on the oldest substrate showed the highest(least negative)δ^(15)N values,but mineral N was the only nutrient whose concentration exhibited a straightforward(increasing)relationship with increasing substrate age.The BAI was largest on the soil with the highest concentration of plant-available P.In contrast to BAI,tree-ring chronologies did not differ among the study sites.However,tree-ring chronologies and BAI exhibited significantly positive correlations with summer precipitation,and negative correlations,with summer(December)temperature.A negative correlation was found betweenδ^(13)C and precipitation anomalies in the growing season(November-March).We interpret the negative correlations between growth and temperature,and betweenδ^(13)C andδ^(18)O in the tree rings,as an impairment of net carbon assimilation by anomalously warm weather conditions during the growing season.We conclude that the growth of N.dombeyi is mainly affected by high temperature and low precipitation in spring and summer irrespective of the substrate’s age,and enhanced by higher concentrations of plant-available P in the soil.Our results may be representative of N.dombeyi stands on volcanic substrate within their principal distribution range along the Andes of South America.
基金funded through Western Sustainable Agriculture Research and Education(SARE),USDA(for NV Hue and A Ahmad)。
文摘Many Hawaiian agricultural soils are acidic with low-nutrient retention;therefore,organic soil amendments are often used to improve soil properties and increase yields.Amendments can be incorporated for annual crops,but perennial orchards need surface application to avoid damaging surface roots.Pot trials compared responses to incorporated(IBC)or surface-applied(SBC)combination of hardwood biochar and chicken manure compost(4%v/v of each amendment)added to an Andisol and Oxisol.Soil pH was increased by 0.4-1.1 units in IBC and by 0.2-0.5 for SBC in the 0-10 cm soil layer.Both SBC and IBC increased soil total N,extractable P,Ca and Mg in the 0-10 cm soil layer.Soil pH,total C and extractable Ca were also higher in the 10-20 cm soil layer for IBC soil,indicating movement and/or leaching of amendments.Chinese cabbage biomass was 18-70%higher in the IBC and 14-47%higher in the SBC than that in the unamended soil,while papaya biomass was 23%and 19%higher in SBC and IBC,respectively.There was a greater response in the more acidic Andisol soil,with larger improvements in soil pH,plant nutrient uptake and root biomass than the Oxisol.Surface application was as effective in increasing plant growth as the incorporated amendment,providing evidence for farm scale assessment.Biochar and compost are recommended for use in tropical soils,and surface application may be beneficial to annual and perennial crops.
