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1.
生物质炭和腐殖质对稻田土壤CH4和N2O排放的影响   总被引：1，自引：0，他引：1  
为探讨生物质炭与腐殖质单独施用与配合施用对稻田土壤CH4和N2O气体排放以及水稻产量的影响。以浙江临安潜育性水稻土的稻田系统为研究对象,设置2个水稻秸秆生物质炭添加水平(0,20 t/hm2)和3个腐殖质水平(0,0.6,1.2 t/hm2),共6个处理,分别为:(1)B0F0(对照,不添加生物质炭和腐殖质);(2)B0F1(腐殖质用量为0.6 t/hm2);(3)B0F2(腐殖质用量为1.2 t/hm2);(4)B1F0(生物质炭用量为20 t/hm2);(5)B1F1(生物质炭和腐殖质用量分别为20,0.6 t/hm2);(6)B1F2(生物质炭和腐殖质用量分别为20,1.2 t/hm2),研究生物质炭和腐殖质输入对水稻产量、稻田CH4和N2O气体排放的影响。结果表明:(1)与B0F0相比,单独施用生物质炭和腐殖质或生物质炭与腐殖质配施均降低了土壤CH4累积排放量,但增加了土壤N2O累积排放量;(2)生物质炭处理对GWP(global warming potential)和GHGI(greenhouse gas intensity)没有显著影响(P>0.05),腐殖质处理显著降低了GWP和GHGI(P<0.05),生物质炭和腐殖质对GWP和GHGI存在显著交互作用(P<0.05);(3)与B0F0相比,单独施用生物质炭和腐殖质或者生物质炭与腐殖质配施均能在一定程度上减少单位水稻产量的温室气体排放强度(GHGI),B0F2处理的GHGI最低,表明单施腐殖质处理(腐殖质用量为1.2 t/hm2)稻田土壤的减排效果和环境效应最好。研究结果为进一步探讨稻田土壤固碳减排提供数据支撑和理论依据。  相似文献   

2.
The influence of vegetational background on binding of selected heavy metals in humus was examined. For this purpose samples of terrestrial humus from surface soil layers with different vegetational background, such as spruce, pine and oak forests, and different types of mires were studied with respect to differences in binding of Cd, Cu, Pb and Zn. The metal binding capacity was examined at different pH using batch extractions. The results indicated that vegetational background influences the binding of metals in organic soil significantly. Drying and storage of the soil samples appeared not to affect the metal binding capacity of the soils. Neither did heating of the samples at 100 °C or incubation at constant temperature and moisture affect the binding significantly, indicating that any fungi or soil microorganisms present did not appreciably affect the metal binding in these soils.  相似文献   

3.
G. Ogner 《Geoderma》1985,35(4):343-353
Crust, felty, greasy and granular raw humus were analysed by wet chemical methods and by 13C NMR. The amounts of amino acids, monosaccharides and aliphatic dicarboxylic acids were determined and the yields compared with the 13C NMR spectra. Protein carbon constitutes 9–13%, polysaccharide carbon 8–19% dicarboxylic acids 1–2% and free carboxylic acid groups 2–4% of the total sample carbon. Degradation of greasy raw humus yields half the amount of monosaccharides and twice the amount of aliphatic dicarboxylic acids found in the other raw humus types. This result is confirmed by 13C NMR. Forty to fifty percent of the soil carbon is unaccounted for among the degradation products identified. Based on estimates of 13C NMR data, the unknown part consists of aliphatic carbon, where the C:O ratio ranges between 1 1.1:1 and 1.8:1. All data indicate great similarity between crust and felty raw humus, whereas greasy raw humus differs clearly from those two. Granular raw humus gives approximately the same amount of degradation products as crust and felty raw humus but differs in its 13C NMR spectrum. The relative proportions of all compounds identified, including aliphatic dicarboxylic acids, are approximately constant, indicating a difference in degree rather than kind of the four raw humus types.  相似文献   

4.
Organic soil samples with different vegetational background and others with variation in the degree of humification, were investigated with solid-state 13C NMR. This work indicates that the vegetational origin and degree of humification of the organic matter appear to influence the distribution of functional groups in organic soils considerably, but one year of decomposition under controlled laboratory conditions gave only small changes in the chemical composition.  相似文献   

5.
In incubation experiments in the laboratory interactions of urea or NH4NO3 with humus from stands of fir (Abies cephalonica, Loudon) growing on soils developed from flysch (shales) and limestone and with humus from stands of black pine (pinus nigra, Arn.) growing on soils developed from peridotites, limestone and schists were investigated.Fir humus from stands on flysch and limestone and black pine humus from limestone showed nitrification but it was absent from black pine humus from stands on peridotites and on schists. Humus from stands on schists showed appreciable ammonification. Increasing concentrations of urea did not initiate nitrification in the latter type of humus. No substantial N immobilization was detected in spite of relatively high P immobilization. Increases in concentration of Ca, Mg and K occurring on incubation of humus samples were related to the ability of a humus type to nitrify rather than to concentrations of added urea-N.Urea was hydrolyzed rapidly to NH+4 during contact with various types of humus, resulting in an increase of pH. Production of NH+4 from urea was only minimally affected by drying the humus samples at 70°C for 20 h before incubation but was reduced to 30% at 1–5°C.  相似文献   

6.
We investigated the effect of continuous compost application on humus composition and N fertility of soils in a field subjected to double cropping (paddy rice and barley) for 25 years. Soil samples were collected from three different plots: (a) No-NF, fertilizer containing P and K but no N; (b) F, fertilizer containing N, P, and K; and (c) F+C, fertilizer plus compost. The amounts of total humus, extracted humus, and humic and fulvic acids increased in the order No-NF<F≪F+C. The amounts of humic and fulvic acids were 2.7 and 1.7 times larger in the F+C plot than in the F plot, respectively. The degree of humification of the humic acids decreased in the order No-NF<F<F+C. The absorption curves and 13C-NMR spectra (TOSS method) of the humic acids indicated the presence of lignin-like structure, and its degree was the strongest in the F+C plot. The 13C-NMR spectra showed distinct differences in the distribution of carbon species between humic and fulvic acids. In humic acids, the content of aromatic-C, ranging from 37 to 44%, was the highest among carbon species. In fulvic acids, the content of O-alkyl-C, ranging from 45 to 51%, was the highest. The amounts of phosphate buffer-extractable N (PEON) and total N (TN) increased in the order No-NF<F<F+C. The amounts of PEON and TN were 1.2 and 1.7 times larger in the F+C plot than in the F plot, respectively. Present and previous findings indicated that continuous compost application could improve various properties of soils in a field subjected to long-term double cropping.  相似文献   

7.
A 22-factorial design with sulphuric acid (pH 3.1) and Cu-Ni addition was used to assess the effects of moderate amounts of continuous acid (Acid and CuNi+Acid) and metal (CuNi and CuNi+Acid) deposition on humus microbial activity and community structure in the field after nine growing seasons. These 20 field experiment samples were also used to measure the suitability of wood ash for remediation. Microcosms were treated with wood ash at a fertilization rate of 5000 kg ha−1, irrigated with water and incubated for 2 months in the dark at 20 °C and a constant relative humidity of 60%. Microcosms only irrigated with water served as a control. Microbial activity was measured as basal respiration. Microbial community structure was determined by phospholipid fatty acid analysis, which mainly targets bacteria. Fungal community structure was assessed by 18S rDNA-targeted polymerase chain reaction-denaturing gradient gel electrophoresis analysis. The bioavailability of Cu was tested with the Pseudomonas fluorescens DF57-Cu15 reporter strain, which bioluminescences in the presence of Cu. Our field study showed, that acid and metal treatments both changed the humus layer microbial community structure. Acid application decreased humus layer pH and base saturation (BS) and increased the amounts of both extractable and bioavailable Cu. Metal application increased the concentration of extractable Ni and changed the fungal community structure. In irrigated laboratory microcosms the above-mentioned treatment effects were still seen except for the acid and metal effects on microbial and fungal community structures. For ash-treated microcosms, neither acid nor metal effects were found for humus layer pH, BS, extractable Cu and Ni, or bioavailable Cu. Thus, wood ash can be used for remediation of acid and metal polluted humus.  相似文献   

8.
Analysis of variance has been carried out between soil samples separated by distances of 0.5 m, 10 m and 0.5–8 km. The samples were taken from the A2 horizon of the Countesswells series iron podzol, thus maintaining the same pedological feature, profile class and parent material. The organic matter has been examined by the pyrolysis characteristics, total carbon and nitrogen, and the cations by exchangeable Ca2+, Mg2+, Na+, K+ and H+, whilst pH and total phosphorus have also been determined. The analysis of variance with respect to distance between the samples shows that all the properties examined exhibit considerable variation over short distances, many showing the major proportion of their total variance at a distance of 0.5 m. This markedly limits the interpretation of data from single samples. Those properties reflecting base status and humus type show, in addition, a variation of similar size over distances of the order of a kilometre.  相似文献   

9.
[14C] and [35S]labeled lignosulfonates (LS) or [14C]labeled coniferyl alcohol dehydropolymer (DHP) were aerobically incubated in soil for 17 weeks. Respiratory 14CO2 was compared with that from DHP or that from [U14C]cellulose. Less CO2 was released from ring and side chain carbons of LS than from DHP, though similar amounts of CO2 were released from the methoxyl groups of both compounds. After incubation, the soil samples were exhaustively extracted with water and then with a sodium pyrophosphate-NaOH solution. The water solubility of the originally completely-soluble LS carbons was greatly decreased by incubation, and a large portion of the extracted 35S was detected as sulfate. The pyrophosphate extract was separated into humic and fulvie acids. The humic acid from soils incubated with LS contained low 35S activity and a similar 14C activity to that from soils incubated with DHP. The fulvic acid from the soils incubated with LS contained higher amounts of 14C (and 35S) than that of the soils incubated with DHP. More side chain 14C activity than other 14C activity was found in both, the water extract and the fulvic acid from soils incubated with LS. The high 35S together with the high side chain 14C activity probably indicates an elimination of the side chain carbons together with sulfonic acid groups. Anaerobic incubation of soil with LS or DHP promoted breakdown and incorporation of LS and DHP into humus much less than aerobic incubation. The possible reduction in potential pollution from lignosulfonates due to the observed transformations in soil are discussed.  相似文献   

10.
Laboratory incubation experiments with and without added urea or NH4NO3 were performed on humus from stands of beech (Fagus silvatica) grown on soils from limestone, schists, flysch and peridotites and on humus from oak (Quercus conferta) stands on soils from limestone and schists.Beech and oak humus from stands grown on soils from limestone and flysch showed considerable nitrification with a concurrent high mobilization rate of the nutrient elements Ca, Mg and K, especially in the presence of increasing urea concentrations, but no net humus N mineralization was observed. Beech humus from stands grown on soils from schists and peridotites showed no nitrification and increasing concentrations of added urea did not modify their inability to nitrify. Non-nitrifying types of humus showed considerable ammonification but their Ca, Mg and K mobilization rates were about one-tenth those observed in nitrifying humus and were inversely correlated with urea concentrations.Exchangeable Al3+ and extractable Mn were present in high concentrations in the underlying inorganic soils in all cases where nitrification was absent from the overlying humus but addition of 500 parts Al3+ and 1000 parts Mn/106 separately or in combination to a nitrifying humus failed to inhibit nitrification.An interpretation of these findings is attempted with reference to the possibility of absence of nitrification in climax vegetations and the preference of certain forest species for NH+4 or NO?3.  相似文献   

11.
《Geoderma》2006,130(1-2):26-34
Aluminum–humus complexes are believed to be highly stable under natural conditions in nonallophanic Andosols. However, it has been shown that the aluminum complexed with humus is easily released by acidic buffer solutions and possibly controls the aluminum solubility of these soils. Thus, it is highly probable that Al–humus complexes are easily influenced by rather simple chemical treatments. We examined the effects of liming (CaCO3 treatment) on Al–humus complexes of A and B horizons from Andosols. It was observed that liming reduced the Al release rates from soil samples with pH 3.5 acetate buffer solution and the amounts of the KCl-extractable Al, suggesting the formation of precipitation from easily exchangeable Al. A much larger decrease with liming was also obtained for 0.1 M sodium pyrophosphate-extractable Al (decrease rates of 7–52%) and 0.5 M CuCl2-extractable Al (decrease rates of 9–43%). These results strongly indicate that liming reduces significant amounts of organically complexed Al as well as the exchangeable Al. The increase in the cation exchange capacity of soils at pH 7 after liming further suggested that the carboxyl group of humus complexed with Al was partly liberated from the Al complexation and became to develop negative charges.  相似文献   

12.
G. Ogner 《Geoderma》1983,29(3):215-219
Humic acids have been prepared from four Norwegian forest soils, namely crust, felty, greasy and granular raw humus. 31P-NMR spectra demonstrated the presence of a variety of phosphorus esters and diesters in all the humic acids investigated. Alkylphosphonic acids and/or esters were present in humic acids from crust and felty raw humus.  相似文献   

13.
Four samples of soil organic matter and their humic acids, fulvic acids and humin were studied with solid-state 13CP MAS NMR. The whole soil samples were fractionated using NaOH and HCl in order to extract humic acids, fulvic acids and humin. This investigation indicates that conventional humus fractionation does not significantly change the content of different functional groups in soil.  相似文献   

14.
Soil biodiversity includes organisms which spend a part or all of their life cycle on or in the soil. Among soil-dwelling animals, macro-fauna as an important group of animals have important effects on the dynamics of soil organic matter and litter decomposition process. The humus forms interact with the climatic conditions, flora, as well as soil fauna, and microbial activity. In new humus form classifications, soil organisms play an important role in separation of humus horizons from one another. The subject of this study was to determine the diversity of macro fauna for different humus forms. We determined humus forms using morphological classification, and then 69 random samples were taken from plots of 100 cm2 in area, and soil macro-fauna species were collected by hand sorting method. Two classes of humus forms, including Mull (with three humus orders, namely Dysmull, Oligomull, and Mesomull,) and Amphi (with four humus orders, namely Leptoamphi, Eumacroamphi, Eumesoamphi, and Pachyamphi) were identified. A number of 13 macro-fauna orders were identified using identification key. Among the humus orders, Shannon diversity, Simpson evenness and Margalef richness indices were the highest in Pachyamphi order. Arthropod diversity in Pachyamphi humus order was higher than those of Mull. These results showed that diversity of soil macrofauna increase by increasing the thickness of the organic horizons (OL, OF, OH), especially OH horizon.  相似文献   

15.
The Pepper Mild Mottle Virus (PMMoV) is a soil-borne virus that causes the mosaic disease to Capsicum ssp. This virus disease had been controlled by soil fumigation using methyl bromide, but the method was banned in 2005. Therefore, a new management and control technology that replaces methyl bromide is required. In the present study, the adsorption of PMMoV by soils that is considered to be one of the most important factors of the virus inactivation was examined. We used eight soil samples with different types of clay compositions and humus contents for the PMMoV adsorption experiments at three different pH levels (pH 4, 5 and 7). Large amounts of PMMoV particles were adsorbed by the soil samples with a low humus content at the low pH. This was attributed to the increase in the positive charges of the soil samples. On the other hand, low virus adsorptions were observed at the pH levels in the soils with a high organic matter content. There were close negative correlations (P < 0.05) between the PMMoV adsorption by the soils and the humus content of the soil samples. We considered that the inhibitory effect of humus against the virus adsorption is rather important in most soils in Japan.  相似文献   

16.
In summer 1994, stream water, moss and humus samples were collected for sulphur isotopic analysis from eight catchments located in the western Kola Peninsula region, where several industrial centres emit high loads of SO2 and other elements to the atmosphere. Three potential sources of sulphur and their isotopic signatures were identified: (1) marine (δ 34S+20 to +21‰ CDT), (2) anthropogenic emissions (<+10‰), and (3) geogenic (variableδ 34S, mostly <+10‰). Averaged per catchment, the sulphur isotopic composition varies between +6.0 and +16.3‰ for stream water sulphate, +6.0 and +8.4‰ for moss sulphur, and +5.2 and +12.2‰ for humus sulphur. Theδ 34S composition of stream water from the more remote catchments is quite variable, reflecting several natural (geogenic) sources, but it becomes restricted to the range +8 to +10‰ near the pollution sources. A plot ofδ 34S vs. 1:SO4 in stream water suggests that sulphate originating from the smelters has aδ 34S value ≈+9.5‰, and is a dominant source. Sulphur isotope values for moss and humus are consistent with the deduced composition for the emitted sulphur, though for humus a component of geogenic sulphur incorporated via vegetation uptake may play a role. Further isotopic characterisation of atmospheric emissions, together with environmental samples, is needed to better understand sulphur sources and sinks in the area.  相似文献   

17.
Near-infrared spectroscopy and soil physicochemical determinations (pHH2O, organic matter content, total C content, NH inf4 sup+ , total N content, cation-exchange capacity, and base saturation) were used to characterize fire-or wood ash-treated humus samples. The spectroscopic and the soil physicochemical analysis data from the humus samples were used separately to explain observed variations in soil respiration and microbial biomass C by partial least-square regression. The first regression component obtained from the physicochemical and spectroscopic characterization explained 10–12% and 60–80% of the biological variation, respectively. This suggests that information on organic material collected from near-infrared spectra is very useful for explaining biological variations in forest humus.  相似文献   

18.
We evaluated the influence of the brown rot fungus Hygrophoropsis aurantiaca on P solubility in the humus layer of a podzolic forest soil. This fungus is known to exude large amounts of oxalic acid that may stimulate weathering of minerals and increase dissolution of humus, which in turn may increase P availability in the soil surrounding the fungus. Humus was inoculated using small wooden pieces colonised by the fungus. The presence of the fungus resulted in elevated concentration of PO4− in the humus solution. In a second experiment birch seedlings grown in the same humus were able to utilise the PO4− mobilised by the fungus to increase their internal P content. The factor determining this increased P uptake and the increased available P might be oxalate produced by fungus. The acid may directly dissolve P or change organic forms of P making it more susceptible to reaction with phosphatases. This fungal effect on P solubility diminished when N was added to the soil in the form of a slow release N fertilizer (methyl urea), or when a soil with a higher soil N concentration was used. We found a strong correlation between NH4+ concentration and total organic carbon in the soil solution at high NH4+ concentrations, suggesting the dissolution of humus as a result of the high NH4+ content in the solution. This study demonstrates that the wood-decaying fungus H. aurantiaca influences nutrient turnover in forest soil, and thereby nutrient uptake by forest trees. An intensified harvest of forest products such as whole tree harvesting may decrease the active biomass of the wood decomposers and may thereby change the availability of P and the leaching of N.  相似文献   

19.
The clay mineralogy of 22 samples of the Ap horizons of Ando soils was determined by a combination of methods. Of these samples, 15 did and 7 did not contain allophane and imogolite. Opaline silica was found in 4 samples, whereas aluminum—humus complexes, iron oxides and layer silicates were found in all samples. The presence of allophane and imogolite and the absence of opaline silica in a few Ap horizons was related to mixing of A1 horizons and subsoils by cultivation and to lower supplies of organic matter relative to the amounts of aluminum released from volcanic ash by weathering. The contents of 2:1 and 2:1:1 layer silicates and their intergrades were larger in soils in which quartz predominated in fine fractions. It was inferred that aluminum bound with humus and in allophane-like constituents, rather than aluminum in allophane and imogolite, is important in reactions with phosphate and fluoride.  相似文献   

20.
Abstract

Heavy metals may alter the structure and metabolic functions of soil microbial community. The objective of our study was to compare the community level physiological proffies (CLPPs) of microbial communities from forest humus polluted with different amounts of Zn, Pb, and Cd to test whether the addition of soluble Zn and Cd may affect the CLPPs of microbial communities. The samples were taken at 18 locations in southern Poland referred to as unpolluted (UP), slightly polluted (SP), and heavily polluted sites (HP). The contents of heavy metals were measured after wet digestions in concentrated HNO3. Microbial communities were extracted using 0.96% NaCl solution. In order to test heavy metal tolerance of microbial communities from UP sites the extracts from these sites were additionally treated with Zn (50 mg L-1; UP + Zn) and Cd (1 mg L-1; UP + Cd). Metabolic functions of the microbial communities were analyzed using BIOLOG Ecoplates method. The contents of Zn, Pb and Cd were the highest at HP sites (4,740, 1,120, 41.0 mg kg-1, respectively) followed by SP (830, 509, 9.2 mg kg-1, respectively), and UP (173, 93, 2.1 mg kg-1, respectively) sites. Principal components analysis (PCA) indicated that CLPPs at all sites were similar. This suggests that microbial community from SP and HP sites revealed tolerance to heavy metals. Addition of Zn affected CLPPs of microbial communities from UP sites as indicated by significantly (p < 0.05) higher value of PC1 score. The addition of Cd did not affect CLPPs of microbial communities from these sites.  相似文献   

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