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Geotechnical investigation of low-plasticity organic soil treated with nano-calcium carbonate 被引量:1
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作者 Govindarajan Kannan Brendan C.O’Kelly Evangelin Ramani Sujatha 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第2期500-509,共10页
Soil stabilization using nanomaterials is an emerging research area although,to date,its investigation has mostly been laboratory-based and therefore requires extensive study for transfer to practical field ap-plicati... Soil stabilization using nanomaterials is an emerging research area although,to date,its investigation has mostly been laboratory-based and therefore requires extensive study for transfer to practical field ap-plications.The present study advocates nano-calcium carbonate(NCC)material,a relatively unexplored nanomaterial additive,for stabilization of low-plasticity fine-grained soil having moderate organic content.The plasticity index,compaction,unconfined compressive strength(UCS),compressibility and permeability characteristics of the 0.2%,0.4%,0.6%and 0.8%NCC-treated soil,and untreated soil(as control),were determined,including investigations of the effect of up to 90-d curing on the UCS and permeability properties.In terms of UCS improvement,0.4%NCC addition was identified as the optimum dosage,mobilizing a UCS at 90-d curing of almost twice that for the untreated soil.For treated soil,particle aggregation arising from NCC addition initially produced an increase in the permeability coef-ficient,but its magnitude decreased for increased curing owing to calcium silicate hydrate(CSH)gel formation,although still remaining higher compared to the untreated soil for all dosages and curing periods investigated.Compression index decreased for all NCC-treated soil investigated.SEM micro-graphs indicated the presence of gel patches along with particle aggregation.X-ray diffraction(XRD)results showed the presence of hydration products,such as CSH.Significant increases in UCS are initially attributed to void filling and then because of CSH gel formation with increased curing. 展开更多
关键词 organic silt Calcium carbonate Nano-calcium carbonate(NCC) Calcium silicate hydrate(CSH) soil stabilization
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Changes in soil organic carbon and aggregate stability following a chronosequence of Liriodendron chinense plantations 被引量:3
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作者 Qicong Wu Xianghe Jiang +2 位作者 Qianwen Lu Jinbiao Li Jinlin Chen 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期355-362,共8页
The objectives for this study were to determine changes in soil organic carbon(SOC)components and water-stable aggregates for soil profi les from diff erent ages of plantations of Liriodendron chinense and to clarify ... The objectives for this study were to determine changes in soil organic carbon(SOC)components and water-stable aggregates for soil profi les from diff erent ages of plantations of Liriodendron chinense and to clarify which organic carbon component is more closely associated with the formation and stability of soil aggregates.Three layers of soil(depths 0–20 cm,20–40 cm,40–60 cm)were collected from young,half-mature and mature stages of L.chinense.SOC,readily oxidizable organic carbon,chemically stable organic carbon and aggregate composition were determined.Intermediate stable organic carbon,the microbial quotient and aggregate stability(mean weight diameter)were calculated.SOC and aggregate stability in the L.chinense plantation did not increase linearly with an increase in L.chinense age;rather,they fi rst decreased,then increased with increasing age of L.chinense.The microbial quotient had a negative eff ect on the level of organic carbon and the stability of aggregates,while chemically stable organic carbon had a positive eff ect,which explained 55.0%and 19.3%of the total variation,respectively(P<0.01).Therefore,more attention should be paid of these two indicators in the future. 展开更多
关键词 soil organic carbon Aggregate stability Liriodendron chinense plantation CHRONOSEQUENCE soil depth
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Effect of Wetland Reclamation on Soil Organic Carbon Stability in Peat Mire Soil Around Xingkai Lake in Northeast China 被引量:1
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作者 HUO Lili ZOU Yuanchun +3 位作者 LYU Xianguo ZHANG Zhongsheng WANG Xuehong AN Yi 《Chinese Geographical Science》 SCIE CSCD 2018年第2期325-336,共12页
Content and density of soil organic carbon(SOC) and labile and stable SOC fractions in peat mire soil in wetland, soybean field and rice paddy field reclaimed from the wetland around Xingkai Lake in Northeast China we... Content and density of soil organic carbon(SOC) and labile and stable SOC fractions in peat mire soil in wetland, soybean field and rice paddy field reclaimed from the wetland around Xingkai Lake in Northeast China were studied. Studies were designed to investigate the impact of reclamation of wetland for soybean and rice farming on stability of SOC. After reclamation, SOC content and density in the top 0–30 cm soil layer decreased, and SOC content and density in soybean field were higher than that in paddy field. Content and density of labile SOC fractions also decreased, and density of labile SOC fractions and their ratios with SOC in soybean field were lower than that observed in paddy field. In the 0–30 cm soil layer, densities of labile SOC fractions, namely, dissolved organic carbon(DOC), microbial biomass carbon(MBC), readily oxidized carbon(ROC) and readily mineralized carbon(RMC), in both soybean field and paddy field were all found to be lower than those in wetland by 34.00% and 13.83%, 51.74% and 35.13%, 62.24% and 59.00%, and 64.24% and 17.86%, respectively. After reclamation, SOC density of micro-aggregates(< 0.25 mm) as a stable SOC fraction and its ratio with SOC in 0–5, 5–10, 10–20 and 20–30 cm soil layers increased. SOC density of micro-aggregates in the 0–30 cm soil layer in soybean field was 50.83% higher than that in paddy field. Due to reclamation, SOC density and labile SOC fraction density decreased, but after reclamation, most SOC was stored in a more complex and stable form. Soybean farming is more friendly for sustainable SOC residence in the soils than rice farming. 展开更多
关键词 soil organic carbon soil organic carbon fractions soil organic carbon stability RECLAMATION wetland
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Formation and Water Stability of Aggregates in Red Soils as Affected by Organic Matter 被引量:39
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作者 ZHANG MINGKUI HE ZHENLI +1 位作者 CHEN GUOCHAO HUANG CHANGYONGI andM. J. WILSON ̄2( ̄1DePartment of Land Use and Applied Chemistry, Zhejiang Agricultural University, Hangzhou 31O029(China))( ̄2Soils and Soil Microbiology Division, Macaulay Land Use Research Inst 《Pedosphere》 SCIE CAS CSCD 1996年第1期39-45,共7页
The water stability of aggregates in various size classes separated from 18 samples of red soils under different managements, and the mechanisms responsible for the formation of water-stable soil aggregates were studi... The water stability of aggregates in various size classes separated from 18 samples of red soils under different managements, and the mechanisms responsible for the formation of water-stable soil aggregates were studied. The results showed that the water stability of soil aggregates declined with increasing size, especially for the low organic matter soils. Organic matter plays a key role in the formation of water-stable soil aggregates. The larger the soil aggregate size, the greater the impact of organic matter on the water stability of soil aggregates. Removal of organic matter markedly disintegrated the large water-stable aggregates (> 2.0 mm) and increased the small ones (< 0.25-0.smm) to some extent, whereas removal of free iron(aluminium) oxides considerably destroyed aggregates of all sizes, especially the < 0.25-0.5 mm classes. The contents of organic matter in water-stable aggregates increased with aggregate sizes. It is concluded from this study that small water-stable aggregates (< 0.25-0.5 mm) were chiefly cemented by Fe and Al oxides whilst the large ones (> 2.0 mm) were mainly glued up by organic matter. Both free oxides and organic matter contribute to the formation and water stability of aggregates in red soils. 展开更多
关键词 AGGREGATE free oxides organic matter red soil water stability
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Effects of organic mulching on soil aggregate stability and aggregate binding agents in an urban forest in Beijing, China 被引量:3
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作者 Wei Zhou Xiangyang Sun +3 位作者 Suyan Li Tiantian Du Yi Zheng Zhihui Fan 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第3期1083-1094,共12页
Urban forest soil is often disturbed by rapid urbanization. Organic mulching is effective for improving soil quality and aggregate stability. This study evaluated how soil binding agents changed aggregate stability th... Urban forest soil is often disturbed by rapid urbanization. Organic mulching is effective for improving soil quality and aggregate stability. This study evaluated how soil binding agents changed aggregate stability through organic mulching in urban forest soils. Three treatments were applied in Jiufeng National Forest Park, Beijing: (1) no organic mulch (control);(2) wood chips alone (5 cm thickness);and, (3) wood chips + wood compost (This mulch was divided into two layers, the upper layer of wood chips (2.5 cm), the lower layer wood compost (2.5 cm)). Soil samples were collected from the surface 10- cm soil layer and fraction into four aggregates. Glomalin-related soil protein and soil organic carbon were measured in bulk soil and the four aggregates. The results show that wood chips + wood compost increased the proportion of large and small macroaggregates, mean weight diameter and geometric mean diameter. The total and easily extractable glomalin-related soil protein were higher in the wood chips + wood compost. However, soil organic carbon was lower in the wood chips alone application compared to the controls and wood chips + wood compost. Easily extractable / total glomalin-related soil protein and glomalin-related soil protein / soil organic carbon ratios of wood chips alone and wood chips + wood compost had increased trend compared to the controls but did not reach significant levels (p > 0.05). Mean weight diameter and geometric mean diameter correlated positively with total and easily extractable glomalin-related soil protein but were not positively correlated with soil organic carbon, the ratios of easily extractable and total glomalin-related soil protein, and the ratios of glomalin-related soil protein and soil organic carbon. Redundancy analysis revealed that total glomalin-related soil protein was the most important driver for soil aggregate stability, especially the total glomalin-related soil protein of small macroaggregates. The results suggest that wood chips + wood compost enhanced soil aggregate stability through the increase of glomalin-related soil protein. Wood chips alone cannot enhance soil aggregate stability in urban forests in the short term. 展开更多
关键词 organic mulching soil aggregate stability soil binding agents Glomalin-related soil protein(GRSP) soil organic carbon(SOC)
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Soil organic carbon contents, aggregate stability,and humic acid composition in different alpine grasslands in Qinghai-Tibet Plateau 被引量:4
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作者 CAO Zhi-yuan WANG Yong +2 位作者 LI Jie ZHANG Jin-jing HE Nian-peng 《Journal of Mountain Science》 SCIE CSCD 2016年第11期2015-2027,共13页
Alpine grassland soils on Qinghai-Tibet Plateau store approximately 33.5 Pg of organic carbon(C) at 0–0.75 m depth and play an important role in the global carbon cycle.We investigated soil organic C(SOC),water-solub... Alpine grassland soils on Qinghai-Tibet Plateau store approximately 33.5 Pg of organic carbon(C) at 0–0.75 m depth and play an important role in the global carbon cycle.We investigated soil organic C(SOC),water-soluble organic C(WSOC),easily oxidizable organic C(EOC),humic C fractions,aggregate-associated C,aggregate stability,and humic acid(HA) composition along an east-west transect across Qinghai-Tibet Plateau,and explored their spatial patterns and controlling factors.The contents of SOC,WSOC,EOC,humic C fractions and aggregate-associated C,the proportions of macroaggregates(2-0.25) and micro-aggregates(0.25-0.053 mm),and the aggregate stability indices all increased in the order alpine desert < alpine steppe < alpine meadow.The alkyl C,O-alkyl C,and aliphatic C/aromatic C ratio of HA increased as alpine desert < alpine meadow < alpine steppe,and the trends were reverse for the aromatic C and HB/HI ratio.Mean annual precipitation and aboveground biomass weresignificantly correlated with the contents of SOC and its fractions,the proportions of macro- and microaggregates,and the aggregate stability indices along this transect.Among all these C fractions,SOC content and aggregate stability were more closely associated with humic C and silt and clay sized C in comparison with WSOC,EOC,and macro- and microaggregate C.The results suggested that alpine meadow soils containing higher SOC exhibited high soil aggregation and aggregate stability.Mean annual precipitation should be the main climate factor controlling the spatial patterns of SOC,soil aggregation,and aggregate stability in this region.The resistant and stable C fractions rather than labile C fractions are the major determinant of SOC stocks and aggregate stability. 展开更多
关键词 soil organic carbon Aggregate stability Humic acid carbon-13 nuclear magnetic resonance Latitudinal transect Qinghai-Tibet Plateau
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Contents of soil organic carbon and nitrogen in water-stable aggregates in abandoned agricultural lands in an arid ecosystem of Northwest China 被引量:6
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作者 WANG Junqiang LIU Lichao +3 位作者 QIU Xiaoqing WEI Yujie LI Yanrong SHI Zhiguo 《Journal of Arid Land》 SCIE CSCD 2016年第3期350-363,共14页
Soil organic matter content in water-stable aggregates(WSA) in the arid ecosystems(abandoned agricultural lands especially) of China is poorly understood. In this study, we examined the WSA sizes and stability, an... Soil organic matter content in water-stable aggregates(WSA) in the arid ecosystems(abandoned agricultural lands especially) of China is poorly understood. In this study, we examined the WSA sizes and stability, and soil organic carbon(OC) and nitrogen(N) contents in agricultural lands with abandonment ages of 0, 3, 12, 20, 30 and 40 years, respectively, in the Minqin Oasis of Northwest China. The total soil OC and N contents at depths of 0–20, 20–40 and 40–60 cm in abandoned agricultural lands were compared to those in cultivated land(the control). Agricultural land abandonment significantly(P0.25 mm) as the age of agricultural land abandonment increased. The effect of abandonment ages of agricultural lands on MWD was determined by the changes of OC and N accumulation in WSA sizes &gt;2 mm. The total OC and N contents presented a stratification phenomenon across soil depths in this arid ecosystem. That is, both of them decreased significantly at depths of 0–20 and 40–60 cm while increased at the depth of 20–40 cm. The WSA sizes &lt;0.053 mm had the highest soil OC and N contents(accounting for 51.41%–55.59% and 42.61%–48.94% of their total, respectively). Soil OC and N contents in microaggregates(sizes 0.053–0.25 mm) were the dominant factors that influenced the variations of total OC and N contents in abandoned agricultural lands. The results of this study suggested that agricultural land abandonment may result in the recovery of WSA stability and the shifting of soil organic matter from the silt+clay(&lt;0.053 mm) and microaggregate fractions to the macroaggregate fractions. However, agricultural land abandonment did not increase total soil OC and N contents in the short-term. 展开更多
关键词 aggregate stability water-stable aggregates agricultural abandonment soil organic carbon total nitrogen northwestern China
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Effects of soil organic matter components and iron aluminum oxides on aggregate stability during vegetation succession in granite red soil eroded areas
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作者 LIN Zhe HUANG Zhi-gang +3 位作者 LIAO Da-lan HUANG Wan-xia HUANG Juan DENG Yu-song 《Journal of Mountain Science》 SCIE CSCD 2022年第9期2634-2650,共17页
Soil aggregates determine the basic structure of soil,and their composition and stability are influenced by the various types of cementitious substances occurring in soil.To explore the main limiting factors of soil a... Soil aggregates determine the basic structure of soil,and their composition and stability are influenced by the various types of cementitious substances occurring in soil.To explore the main limiting factors of soil aggregation in the process of vegetation succession with granite as the parent material,five stages of vegetation succession in an eroded area were selected:bare land(BL),grassland(GL),grassland shrub transition land(GS),shrubland(SL)and secondary forest(SF).Soil samples were collected to determine the composition and stability of aggregates.The contents of organic and inorganic cementitious substances,including organic matter components and iron aluminum oxides,were determined at five soil aggregate grain levels.The results indicated that the stability of soil aggregates and the>0.25 mm water-stable aggregate content(WR_(0.25))increased with vegetation succession.Based on the Le Bissonnais(LB)method,the mean weight diameter(MWD)of soil aggregates increased,and the relative dissipation index(RSI)and relative mechanical crushing index(RMI)decreased.The humic acid(HA)and fulvic acid(FA)contents in soil aggregates increased with vegetation succession,and the soil humus content at the SF stage increased by more than 13.54%over the BL level.Upon different vegetation succession stage,the iron and aluminum oxides for the SL and the SF were at a high level,and the contents of free-form iron oxide(Fe_(d))and amorphous iron oxide(Fe_(o))for BL were high.Correlation analysis indicated that the soil humic degree(PQ)and the contents of amorphous alumina(Al_(o))were positively correlated with aggregate stability to varying degrees.Redundancy analysis(RDA)revealed that PQ values of 1-2 mm(PQ_(2))and 0.25-0.5 mm(PQ_(4))aggregates,the contents of Fe_(o) of bulk soil(Fe_(oB)),>2 mm(Fe_(o1)),1-2 mm(Fe_(o2)),and<0.25 mm(Fe_(o5))aggregates,and the contents of Al_(o) of>2 mm(Al_(o1))aggregates could explain 99.4%of the changes in soil aggregate stability at different vegetation succession stages.Al_(o1) had a contribution rate of 71.2%and is the key factor for improving the stability of soil aggregates. 展开更多
关键词 soil aggregate stability Vegetation succession soil organic matter components Iron aluminum oxides
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Structural Stability and Accumulation of Organic Matter in Some Soils under Cashew Tree Orchards in the Department of Touba in North-West Cote d’Ivoire
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作者 Alui Konan Alphonse Ballo Koffi Celestin +1 位作者 Kouassi Kouakou Joselin Yao-Kouame Albert 《Open Journal of Soil Science》 2020年第5期181-193,共13页
Degradation of the physical quality of the soil is a common problem encountered in agrosystems, particularly in the case of open field cropping systems in the northern areas of C&#244;te d’Ivoire. Thus, the struc... Degradation of the physical quality of the soil is a common problem encountered in agrosystems, particularly in the case of open field cropping systems in the northern areas of C&#244;te d’Ivoire. Thus, the structural stability of the soil, which is a good indicator of the sensitivity to threshing and to water erosion in relation to the accumulation of organic matter, was evaluated in two types of soil (Ferralsol and Cambisol) in cashew orchards, in two villages (Mahana and Sanankoro) producing cashew nuts, located the Department of Touba in the North West of C&#244;te d’Ivoire. The objective of this study is to develop new technical routes that are better suited to further promote the sequestration of organic carbon in the soil. Soil samples were taken from open soil profiles at the two chosen sites to allow laboratory analyzes. The results indicate that the surface horizon of Cambisol (site 1) is more stable (Is = 0.78) than that of Ferralsol (site 2;Is = 1.08) with nevertheless relatively small thicknesses of horizons. The median horizons and those of depth, indicate a mediocre stability (Is vary from 1.03 to 1.62). In terms of the quantity of organic carbon, the estimated values vary from 1.96 to 4.53 t&sdot;ha&minus;1 for Cambisol (site 1) and from 1.44 to 3.46 t&sdot;ha&minus;1 for Ferralsol (site 2). These values remain relatively low especially at the level of the median horizons and those located in depths. Statistical tests have shown a very highly significant and negative association between the structural stability of soils and the amount of organic carbon in the different horizons. The relationship implies that organic carbon plays an important role in the structural stability of soil horizons under cashew tree orchards. 展开更多
关键词 Structural stability organic carbon soilS CASHEW Cote d’Ivoire
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Aggregate stability and associated C and N in a silty loam soil as affected by organic material inputs 被引量:7
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作者 LONG Pan SUI Peng +6 位作者 GAO Wang-sheng WANG Bin-bin HUANG Jian-xiong YAN Peng ZOU Juan-xiu YAN Ling-ling CHEN Yuan-quan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第4期774-787,共14页
To make recycling utilization of organic materials produced in various agricultural systems, five kinds of organic materials were applied in a field test, including crop straw (CS), biogas residue (BR), mushroom r... To make recycling utilization of organic materials produced in various agricultural systems, five kinds of organic materials were applied in a field test, including crop straw (CS), biogas residue (BR), mushroom residue (MR), wine residue (WR), pig manure (PM), with a mineral fertilizer (CF) and a no-fertilizer (CK) treatment as a control. Our objectives were: i) to quantify the effects of organic materials on soil C and N accumulation; ii) to evaluate the effects of organic materials on soil aggregate stability, along with the total organic carbon (TOC), and N in different aggregate fractions; and iii) to assess the relationships among the organic material components, soil C and N, and C, N in aggregate fractions. The trial was conducted in Wuqiao County, Hebei Province, China. The organic materials were incorporated at an equal rate of C, and combined with a mineral fertilizer in amounts of 150 kg N ha^-1, 26 kg P ha^-1 and 124 kg K ha-1 respectively during each crop season of a wheat-maize rotation system. The inputted C quantity of each organic material treatment was equivalent to the total amount of C contained in the crop straw harvested in CS treatement in the previous season. TOC, N, water-stable aggregates, and aggregate-associated TOC and N were investigated. The results showed that organic material incorporation increased soil aggregation and stabilization. On average, the soil macroaggregate proportion increased by 14%, the microaggregate proportion increased by 3%, and mean-weight diameter (MWD) increased by 20%. TOC content followed the order of PM〉WR〉MR〉BR〉CS〉CK〉CF; N content followed the order WR〉PM〉MR〉BR〉CS〉CF〉CK. No significant correlation was found between TOC, N, and the quality of organic material. Soil silt and clay particles contained the largest part of TOC, whereas the small macroaggregate fraction was the most sensitive to organic materials. Our results indicate that PM and WR exerted better effects on soil C and N accumulation, followed by MR and BR, suggesting that organic materials from ex situ farmland could promote soil quality more as compared to straw returned in situ. 展开更多
关键词 organic materials AGGREGATES soil organic carbon soil nitrogen stabilization
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Soil organic carbon pool along different altitudinal level in the Sygera Mountains, Tibetan Plateau 被引量:6
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作者 MA He-ping YANG Xiao-lin +2 位作者 GUO Qi-qiang ZHANG Xin-jun ZHOU Chen-ni 《Journal of Mountain Science》 SCIE CSCD 2016年第3期476-483,共8页
Labile organic carbon(LOC) is one of the most important indicators of soil organic matter quality and dynamics elevation and plays important function in the Tibetan Plateau climate. However, it is unknown what the s... Labile organic carbon(LOC) is one of the most important indicators of soil organic matter quality and dynamics elevation and plays important function in the Tibetan Plateau climate. However, it is unknown what the sources and causes of LOC contamination are. In this study, soil organic carbon(SOC), total nitrogen(TN), microbial biomass carbon(MBC), microbial biomass nitrogen(MBN) and LOC were analyzed based on different soil horizons and elevations using turnover time in an experimental site(3700 m to 4300 m area) in Sygera. SOC and LOC in higher-elevation vegetation types were higher than that of in lower-elevation vegetation types. Our results presented that the soil microbial biomass carbon(SMBC) and soil microbial biomass nitrogen(SMBN)were positively correlated with SOC. The content of easily oxidized carbon(EOC), particulate organic carbon(POC) and light fraction organic carbon(LFOC) decreased with depth increasing and the content were the lowest in the 60 cm to 100 cm depth.The total SOC, ROC and POC contents decreased with increasing soil horizons. The SOC, TN, MBC and MBN contents increased with increasing altitude in the Sygera Mountains. The MBC and MBN contents weredifferent with the changes of SOC(p&lt;0.05),meanwhile, both LFOC and POC were related to total SOC(p&lt;0.05). The physical and chemical properties of soil, including temperature, humidity, and altitude,were involved in the regulation of SOC, TN, MBC,MBN and LFOC contents in the Sygera Mountains,Tibetan Plateau. 展开更多
关键词 Labile soil organic Easily oxidized carbon KMn O_4 Light fraction organic carbon Particulate organic carbon
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Impacts of long-term ridge culture on aggregate stability in purple paddy soil of Sichuan basin
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作者 唐晓红 《Journal of Chongqing University》 CAS 2010年第4期185-194,共10页
Ridge culture is a special conservation tillage method, but the long-term influence of this tillage system on soil aggregate-size stability in paddy fields is largely unknown in southwest of China. The paper is to eva... Ridge culture is a special conservation tillage method, but the long-term influence of this tillage system on soil aggregate-size stability in paddy fields is largely unknown in southwest of China. The paper is to evaluate soil aggregate stability and to determine the relationship between soil organic carbon (SOC) and soil aggregate stability. Soil samples at 0 cm-20 cm layer were adopted from a long-term (16 a) field experiment including conventional tillage: plain culture, summer rice crop and winter upland crop under drained conditions (PUR-r); and conservation tillage: ridge culture without tillage, summer rice and winter fallow with floodwater layer annually (NTR-f), winter upland crop under drained conditions (NTR-r), and wide ridge culture without tillage, summer rice crop and winter upland crop under conditions (NTRw-r), respectively. Different pretreatments, such as slaking in fast wetting, wetting and subsequent slaking, were applied to simulate the breakdown mechanisms of aggregates in paddy soil. The results show that soil particles contents were mainly consisted of silt (0.050 mm to 1.000 mm) in fraction of 42.9% to 51.2%, sand (0.050 mm to 0.001 mm) in fraction of 28.0% to 31.8%, and clay (<0.001 mm) in fraction of 17.9% to 25.4%. The amount of aggregate-size was greatly observed in fraction of 2.000 mm-6.720 mm under ridge culture in paddy soil (more than 50$) under slaking and wetting pretreatment. The proportion of soil macro-aggregates (>0.250 mm) in conservation tillage was greatly higher than that in conventional tillage under subsequent fast slaking treatment. Minimal differences of aggregate stability between slaking in fast wetting and wetting were observed, while significant differences were found between ridge culture and plain culture. The aggregate stability under slaking treatment ranked in the order of NTR-r>NTRw-r> NTR-f > PUR-r, while under wetting was NTRw-r > NTR-r > NTR-f >PUR-r. There was a positive correlation between the aggregate stability and SOC concentration under wetting, and a low correlation was observed under slaking pretreatment. Soil exposure with tillage and lack of rice/rape-seed stubble inputs caused declines in aggregation and organic carbon, both of which make soil susceptible to water erosion. Adoption of ridge culture with no-tillage integrated with crop rotation and stubble mulch significantly altered soil organic concentration. It was a valuable conservation practice for soil aggregation and soil organic carbon sequestration on paddy soil. 展开更多
关键词 ridge culture ROTATION aggregate stability organic carbon paddy soil
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Aggregate binding agents improve soil aggregate stability in Robinia pseudoacacia forests along a climatic gradient on the Loess Plateau,China 被引量:6
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作者 JING Hang MENG Min +1 位作者 WANG Guoliang LIU Guobin 《Journal of Arid Land》 SCIE CSCD 2021年第2期165-174,共10页
The distribution of binding agents(i.e.,soil organic carbon(SOC)and glomalin-related soil protein(GRSP))in soil aggregates was influenced by many factors,such as plant characteristics and soil properties.However,how t... The distribution of binding agents(i.e.,soil organic carbon(SOC)and glomalin-related soil protein(GRSP))in soil aggregates was influenced by many factors,such as plant characteristics and soil properties.However,how these factors affect binding agents and soil aggregate stability along a climatic gradient remained unclear.We selected the Robinia pseudoacacia L.forests from semi-arid to semi-humid of the Loess Plateau,China to analyze the plant biomass,soil physical-chemical properties,SOC and GRSP distribution in different sized soil aggregates.We found that from semi-arid to semi-humid forests:(1)the proportion of macro-aggregates(>0.250 mm)significantly increased(P<0.05),whereas those of micro-aggregates(0.250–0.053 mm)and fine materials(<0.053 mm)decreased and soil aggregate stability was increased;(2)the contents of SOC and GRSP in macro-aggregates and micro-aggregates significantly increased,and those in fine materials decreased;(3)the contribution of SOC to soil aggregate stability was greater than those of total GRSP and easily extractable GRSP;(4)soil properties had greater influence on binding agents than plant biomass;and(5)soil aggregate stability was enhanced by increasing the contents of SOC and GRSP in macro-aggregates and soil property was the important part during this process.Climate change from semi-arid to semi-humid forests is important factor for soil structure formation because of its positive effect on soil aggregates. 展开更多
关键词 binding agents GLOMALIN organic carbon soil property soil aggregate stability
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Effects of Organic Manure Applications on Methane and Nitrous Oxide Emissions in Paddy Fields 被引量:2
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作者 WU Jia-mei JI Xiong-hui +5 位作者 PENG Hua XIE Yun-he GUAN Di TIANFa-xiang ZHU Jian HUO Lian-jie 《Agricultural Science & Technology》 CAS 2018年第2期36-48,共13页
This study was carried out in paddy fields to explore how organic manure applications would affect greenhouse emissions in South China. The results showed that the seasonal emission of CH4 under the chemical fertiliz... This study was carried out in paddy fields to explore how organic manure applications would affect greenhouse emissions in South China. The results showed that the seasonal emission of CH4 under the chemical fertilizer (CF) treatment was 271.47 kg/hm^2. In comparison, the seasonal emissions of CH4 under the treatment of pig manure (PM), chicken manure (CM) and rice straw (RS) increased by 50.61,260.22 and 602.82 kg/hm^2, respectively. N2O emission under the CF treatment was 1.22 kg/hm^2, while the N20 seasonal emissions under tile PM, CM and RS treatment decreased by 23.6% (P〈0.05), 31.7% (P〈0.05) and 30.9% (P〈0.05), respectively. Meanwhile, the readily oxidized organic carbon (which was oxidized by 167 mmol/L potassium permanganate, ROC167) of manure, paddy soil Eh value and temperature could also affect the CH4 emissions. The average yield of the organic fertilizer treatments increased by 6.8% compared with that of the CF treatment. Among all the organic fertilizer treatments, the PM treatment offered the lowest global warming potential and greenhouse gas intensity, in which the PM was of no significant difference from NF (no fertilizing) and CF. Therefore, the pig manure is capable of coordinating the relationship between environment and yield, and it also has a low ROC167 content, so the PM is considered worthy of recommendation. 展开更多
关键词 Paddy field Methane emission Nitrous emission soil Eh value Readily oxidized organic carbon Greenhouse gas intensity
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自动滴定仪测定土壤有机碳及其组分的方法优化
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作者 李朝英 郑路 +3 位作者 郑之卓 李华 王亚南 明安刚 《岩矿测试》 CAS CSCD 北大核心 2024年第4期632-640,共9页
土壤有机碳及其组分(颗粒有机碳、矿物结合态有机碳等)是反映土壤质量的关键性指标,开展准确高效地测定这些指标对相关研究具有重要意义。自动滴定仪与传统人工滴定相比,人员工作强度低,检测准确,但检测效率不及人工滴定的30%。为解决... 土壤有机碳及其组分(颗粒有机碳、矿物结合态有机碳等)是反映土壤质量的关键性指标,开展准确高效地测定这些指标对相关研究具有重要意义。自动滴定仪与传统人工滴定相比,人员工作强度低,检测准确,但检测效率不及人工滴定的30%。为解决此问题,本文探讨了4种氧化剂加入量对测定有机碳的影响,研究了提前预加滴定液对检测效率提高的效果。最终优选氧化剂加入量为2mL,预加滴定液量以空白样滴定量的1/3计,建立了用于测定土壤有机碳的自动滴定仪法。采用有机碳不同水平的土壤样品和标准物质对方法进行验证,并与人工滴定进行比较,结果表明,自动滴定仪法与人工滴定法无显著性差异,方法的相对标准偏差(RSD,n=6)在2.10%~12.96%,加标回收率在93.37%~98.06%,标准物质相对误差为4.31%~4.79%;优化后的自动滴定法单个试样滴定用时由11min缩短到3.5min,整体检测效率高于人工滴定,而试剂耗用量仅是人工滴定法的40%。自动滴定仪法显著提升了有机碳的检测能力。 展开更多
关键词 自动滴定仪 人工滴定 土壤有机碳 氧化剂加入量 预加滴定量
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长期不同施氮量下黑土团聚体稳定性及有机碳含量的变化 被引量:4
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作者 姚俊红 武俊男 +4 位作者 王呈玉 崔炎田 高云航 孙嘉璐 刘淑霞 《农业环境科学学报》 CAS CSCD 北大核心 2024年第1期102-110,共9页
为测定不同氮肥施用量对黑土团聚体组成及稳定性、有机碳含量及团聚体有机碳分布的影响,阐明黑土有机碳稳定性对不同施氮水平的响应机制,本研究在吉林省梨树县不同施氮水平长期定位试验田进行取样,以施氮水平不同设置5个处理,分别为T1(0... 为测定不同氮肥施用量对黑土团聚体组成及稳定性、有机碳含量及团聚体有机碳分布的影响,阐明黑土有机碳稳定性对不同施氮水平的响应机制,本研究在吉林省梨树县不同施氮水平长期定位试验田进行取样,以施氮水平不同设置5个处理,分别为T1(0)、T2(160 kg·hm^(-2))、T3(240 kg·hm^(-2))、T4(280 kg·hm^(-2))、T5(320 kg·hm^(-2)),分析长期不同施氮量下水稳性团聚体组成、团聚体结构特征、土壤总有机碳含量及团聚体有机碳分布的变化,探究酸化黑土有机碳含量影响特征。结果表明:随氮肥施用水平的升高,土壤碱解氮(AN)和全氮(TN)含量先增后减,T3处理含量最高,AN和TN分别比T1处理高24.90%、10.28%;土壤速效磷(AP)的含量呈下降趋势。随氮肥用量的提高,土壤团聚体呈现大粒径团聚体向小粒径团聚体转变的趋势,>2 mm粒径团聚体下降14.55%。土壤有机碳总量随施氮水平的提高呈先增后减的趋势,施氮量为280 kg·hm^(-2)有机碳含量最高;>2 mm和2~0.25 mm粒径团聚体有机碳含量较高;不同施氮水平下有机碳含量与团聚体稳定性特征的几何平均直径、土壤团聚体破坏率、不稳定团粒指数和土壤化学性质的相关度较高。研究表明:通过13 a连续施入不同水平氮肥,土壤有机碳含量随氮肥施用量的增加呈先增后减的趋势;氮肥施用量增加会显著降低土壤pH,土壤团聚体有机碳主要分布在2~0.25 mm粒径中。 展开更多
关键词 氮肥施用量 黑土 土壤理化性质 团聚体有机碳 团聚体稳定性
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长期施肥对黑土和棕壤团聚体稳定性的影响及驱动因素
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作者 李天娇 张乃于 +7 位作者 申文艳 宋天昊 刘红芳 刘晓燕 张秀芝 彭畅 杨劲峰 张淑香 《中国农业科学》 CAS CSCD 北大核心 2024年第19期3835-3847,共13页
【目的】比较长期不同施肥措施对两种典型土壤(黑土和棕壤)团聚体分布和稳定性的影响,探究影响团聚体稳定性的关键因素,为缓解土壤结构退化提供理论支撑。【方法】依托34年黑土和45年棕壤长期定位试验,选取两定位点共有的不施肥(CK)、化... 【目的】比较长期不同施肥措施对两种典型土壤(黑土和棕壤)团聚体分布和稳定性的影响,探究影响团聚体稳定性的关键因素,为缓解土壤结构退化提供理论支撑。【方法】依托34年黑土和45年棕壤长期定位试验,选取两定位点共有的不施肥(CK)、化肥(NPK)、化肥配施有机肥(NPKM)处理,以及黑土特有的化肥配施秸秆(NPKS)处理、棕壤特有的有机肥——猪厩肥(M)处理,采集0—20 cm土层土壤样品,测定土壤化学性质,采用湿筛法对土壤团聚体进行筛分。【结果】相比于CK,NPK处理下黑土和棕壤大团聚体(>0.25 mm)比例显著降低8.6%和11.3%,团聚体平均重量直径(MWD)分别显著减少18.6%和10.7%,说明单施化肥导致黑土和棕壤团聚体稳定性显著降低;NPKM和M处理下棕壤的MWD分别显著增加44.2%和17.9%,而NPKM处理下黑土MWD未发生显著变化,但NPKS处理下黑土MWD显著提高11.8%,说明在棕壤中施用猪厩肥,黑土中秸秆还田是提高团聚体稳定性的重要措施。土壤团聚体的稳定性主要受土壤化学性质的影响。长期施用化肥(NPK)导致黑土和棕壤的pH和交换性钙、镁离子(Ca^(2+)、Mg^(2+))降低,阻碍了大团聚体的形成和稳定。施用有机物料(M、NPKM、NPKS)抑制了土壤pH的降低,提高土壤颗粒态有机碳(POC)和矿物结合态有机碳(MAOC)的含量,促进有机碳与铁铝氧化物、钙镁离子的结合,推动了黑土和棕壤颗粒的团聚过程,进而维持和提高了团聚体的稳定性。综合分析表明,影响黑土团聚体稳定的因素从大到小依次为络合态氧化铝(Al_(p))、Ca^(2+)、POC、pH、MAOC,其中黑土团聚体稳定性与Al_(p)显著负相关,与其余因素显著正相关。影响棕壤团聚体稳定性的关键因素从大到小依次为POC、络合态氧化铁(Fe_(p))、pH、Mg^(2+)、Ca^(2+)、无定形态氧化铝(Al_(o))、Al_(p)、无定形态氧化铁(Fe_(o)),其中棕壤团聚体稳定性与Al_(o)和Fe_(o)显著负相关,与其他因素显著正相关。【结论】化肥配施有机物料(猪厩肥、秸秆)可以抑制土壤酸化,通过增加土壤POC和Ca^(2+)含量,提高黑土和棕壤团聚体的稳定性,是延缓土壤结构退化的重要施肥措施。 展开更多
关键词 长期施肥 黑土 棕壤 团聚体稳定性 有机碳组分 铁铝氧化物
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黑土与潮土铁氧化物结合态有机碳对长期秸秆还田的响应
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作者 孙悦 任科宇 +7 位作者 邹洪琴 高洪军 张水清 李德近 李冰洁 廖楚芊 段英华 徐明岗 《中国农业科学》 CAS CSCD 北大核心 2024年第19期3823-3834,共12页
【目的】旨在探究不同旱地土壤中不同类型铁氧化物结合态有机碳含量和性质的差异及其对长期秸秆还田的响应。【方法】基于1990年开始位于我国吉林公主岭和河南郑州的黑土和潮土长期定位施肥试验,选择长期定位试验中的不施肥对照(CK)、... 【目的】旨在探究不同旱地土壤中不同类型铁氧化物结合态有机碳含量和性质的差异及其对长期秸秆还田的响应。【方法】基于1990年开始位于我国吉林公主岭和河南郑州的黑土和潮土长期定位施肥试验,选择长期定位试验中的不施肥对照(CK)、单施化肥(NPK)和化肥+秸秆还田(NPKS)3个处理进行。通过连续浸提法获取土壤中络合铁(Fe_(PP))、非晶型铁氧化物(Fe_(HH))及晶型铁氧化物(Fe_(DH)),探究不同形态铁氧化物及其结合态有机碳的含量差异;结合紫外可见光谱分析,探究铁氧化物结合态有机碳的性质差异。【结果】与CK及NPK处理相比,NPKS处理下黑土有机碳含量显著提高了18.1%和14.9%,潮土有机碳含量显著提高了46.1%和13.3%。两种土壤中Fe_(PP)含量均低于Fe_(HH)及Fe_(DH)含量,但络合铁结合态有机碳(OC_(PP))含量明显高于非晶型铁氧化物结合态有机碳(OC_(HH))及晶型铁氧化物结合态有机碳(OC_(DH))含量,可占总铁氧化物结合态有机碳含量的71.4%—93.2%,说明OC_(PP)是铁氧化物结合有机碳的主要存在形态。与NPK相比,NPKS处理黑土中Fe_(PP)含量显著降低了65.6%,Fe_(HH)含量显著降低了17.8%,Fe_(DH)含量没有显著变化;潮土中Fe_(PP)含量显著增加了15.9%,Fe_(HH)含量没有显著变化,Fe_(DH)含量显著提高了24.6%。NPKS较NPK处理显著降低了黑土中总铁氧化物结合有机碳的含量,其中OC_(PP)降低了11.3%,OC_(DH)增加了53.7%,OC_(HH)没有显著变化,而对潮土中总铁氧化物结合有机碳含量没有显著影响。进一步对每克铁氧化物结合有机碳含量的分析发现,与NPK相比,NPKS处理显著增加了黑土中3种铁氧化物结合有机碳的能力,而对潮土中结合有机碳的能力没有显著影响。Fe_(PP)主要与疏水性较强、芳香性较弱的大分子有机碳结合,Fe_(HH)主要与疏水性、芳香性均较强的小分子有机碳结合,而Fe_(DH)主要与一些疏水性及芳香性均较差的大分子化合物结合。【结论】与单施化肥相比,长期秸秆还田后黑土和潮土中晶型和非晶型铁氧化物结合有机碳的含量均显著增加,而络合铁结合有机碳在黑土中显著降低,在潮土中无变化。这是秸秆还田后土壤有机碳水平提升且在土壤类型中存在差异的重要机制之一。 展开更多
关键词 长期秸秆还田 土壤有机碳 有机碳性质 铁氧化物
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放牧强度对高寒草地土壤团聚体稳定性及有机碳含量影响
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作者 甘安琪 姜佳昌 +6 位作者 李霞 王依婷 徐天宇 牛得草 杨晓霞 董全民 郭丁 《草地学报》 CAS CSCD 北大核心 2024年第6期1832-1842,共11页
土壤团聚体与土壤有机碳固存密切相关。本研究依托青藏高原高寒草地家畜系统适应性管理技术平台,系统研究了0~30 cm土层不同放牧强度对土壤团聚体稳定性和有机碳含量影响。结果表明,与禁牧对照相比,中度放牧处理下0~10 cm土层(表层)土... 土壤团聚体与土壤有机碳固存密切相关。本研究依托青藏高原高寒草地家畜系统适应性管理技术平台,系统研究了0~30 cm土层不同放牧强度对土壤团聚体稳定性和有机碳含量影响。结果表明,与禁牧对照相比,中度放牧处理下0~10 cm土层(表层)土壤大团聚体质量分数和平均重量直径(Mean weight diameter,MWD)分别提高了13.43%和12.50%。所有放牧处理均降低了10~30 cm土层(亚表层)土壤大团聚体质量分数和MWD。与对照相比,中度放牧下表层土壤大团聚体有机碳含量显著降低了8.02%;中度和重度放牧处理下,亚表层土壤大团聚体有机碳贡献率分别降低了29.85%和32.75%。MWD与大团聚体质量分数和有机碳贡献率呈显著正相关,与微团聚体和粉粘粒团聚体质量分数及有机碳贡献率呈显著负相关。该研究表明放牧强度对亚表层土壤团聚体特征的影响高于表层土壤,这为探究放牧管理对高寒草地土壤质量和结构影响提供理论基础。 展开更多
关键词 高寒草地 放牧强度 团聚体有机碳 团聚体稳定性
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带状采伐初期对华西雨屏区杉木人工林土壤碳组分及稳定性的影响
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作者 吴章明 唐思莹 +7 位作者 宋思宇 李聪 刘丽鸽 朱鹏 徐红伟 张学强 张健 刘洋 《四川农业大学学报》 CSCD 北大核心 2024年第4期847-860,878,共15页
【目的】旨在相同采伐强度下确定不同带宽采伐带和保留带对土壤碳组分及其稳定性的影响。【方法】在华西雨屏区洪雅林场人工林生态系统研究长期科研基地内,以集水区为功能单元,对23 a生的杉木人工林进行40%相同强度不同带宽的3种带状采... 【目的】旨在相同采伐强度下确定不同带宽采伐带和保留带对土壤碳组分及其稳定性的影响。【方法】在华西雨屏区洪雅林场人工林生态系统研究长期科研基地内,以集水区为功能单元,对23 a生的杉木人工林进行40%相同强度不同带宽的3种带状采伐处理,分别是S1(10 m采伐+15 m保留)、S2(20 m采伐+30 m保留)和S3(30 m采伐+45 m保留),在采伐1 a后进行土壤样品采集。【结果】(1)与未采伐杉木纯林相比,采伐带0~20 cm土层土壤有机碳含量均显著降低;(2)夏季0~40 cm土层的S2采伐带有机碳稳定性显著高于其他两个带宽,而S2保留带显著低于其他两个带宽;冬季表现为S1显著高于其他2个带宽;(3)冗余分析表明,微生物生物量碳与土壤有机碳各组分具有明显的协同作用;(4)土壤碳稳定性与可溶性有机碳含量呈显著正相关,与活性有机碳组分呈显著负相关。【结论】在40%采伐强度下,适宜选择S1带状采伐组合更有利于保持土壤有机碳含量和稳定性。研究结果为杉木人工林的近自然改造和指导林业碳汇经营提供了理论依据。 展开更多
关键词 杉木人工林 带状采伐 土壤有机碳 土壤碳稳定性
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