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1.
基于CNKI及Web of Science数据库,利用Citespace软件,对该方面的研究主要结构、研究基础、热点问题及趋势等开展分析,探讨有机质对重金属生物有效性的影响。以中科院为代表的中国研究机构对该领域的研究做出了巨大贡献,发文总量占31.8%。该领域大多数文献发表在Science of the Total Environment及Chemosphere等国际期刊。根据WoS文献共被引分析,得到该领域研究共识主要有三个方面:一是重金属形态对其生物有效性影响巨大;二是植物吸收、动物积累重金属与有机质及其他环境因素密切相关;三是有机质与重金属的相互作用如溶解－沉淀、氧化－还原等是影响重金属迁移转化及生物有效性的机制。根据关键词共现分析,得到该领域国际研究的热点类型共11类。通过WoS文献高被引文献分析,研究主要集中在不同来源有机质与重金属在固相、液相体系环境中相互作用,对重金属的活化或固定的作用机制及相关应用。根据关键词突现分析,该领域“大米”、“生物炭”、“修复”等是目前国际研究热点。 相似文献
2.
Relations between soil fertility parameters and sugar beet yield and quality characteristics respectively, on Haplic Chernozem soils In interpreting four “experiments without interference” (VoE) on a total of 435 plots the influence of soil fertility parameters (BFKi) as organic matter, P, K, Mg, pH value, Cu, B and Mn on sugar beet yield and its nutrient contents on Haplic Chernozem sites under Ca immission has been analysed. “VoE” is a method applied to find specific field data by means of which relations within the multidimensional system soil - plant are ascertained by utilizing soil and yield parameter variations. With increasing pH value the nutrient contents in the soil decreased in the order the following sequence: Mn, Mg. Cu, B; and, resulting from that, the sugar beet yield decreased significantly. The coefficients of determination (B) of the triple linear regression between yield and BFKi ranged from B = 0,21 to B = 0,33 and between nutrient contents and BFKi from B = 0 to B = 0,41. Most of the regression functions contained “BFKi boron” as a variable. It has been found that there were positive correlations between “BFKi pH value” and “soluble ashes” and negative correlations between “BFKi pH value” and P contents in sugar beet. 相似文献
3.
For twenty‐one years, soil information and knowledge in Victoria, Australia has been shared via the Victorian Resources Online (VRO) website. VRO has been the primary online repository for soil and landscape information generated from land resource assessment studies, field days, training workshops, and the visualization and animation of soil and landscape processes. User surveys and qualitative feedback have highlighted the value of online soil information to users, with many considering it a useful “tool of trade,” particularly those involved in agricultural research, extension, planning and education. An extensive series of “Healthy Soils” training workshops (2007–2010) focused on topics such as “soil types and structure,” “soil chemical testing,” “soil biology,” “soil erosion” and “organic matter.” Evaluation has demonstrated their usefulness and relevance, with learning outcomes achieved by >80% of overall participants, many of whom planned to make better management decisions and change management practices on‐farm. The information and knowledge generated through the series of workshops remains a valuable online resource. The development of more sophisticated knowledge visualization tools, such as animations, has broadened the potential audience for soil‐related information. Analytical profiling of VRO users in recent years has highlighted it as a source of information and knowledge for a local, national and international audience. This supports the notion that increasing access to public‐sector data and information provides significant benefits. Lessons learnt from enduring programs such as VRO can inform future information and knowledge management initiatives. 相似文献
4.
The definition of humusforms from soils under cultivation. II. Quantity and quality of soil organic matter In the new edition of the German textbook “Practical Studies in Soil Science” the authors presented a proposal of mapping humusforms in arable soils in order to characterize soil and site ecology (Schlichting et al., 1995). This proposal was developed from the definitions “Ochric”, “Mollic” and “Umbric” of the Soil Taxonomy and the FAO classification. The characterization of humusforms in 45 arable surface soils was carried out according to this proposal while soil organic matter (SOM) composition was investigated by means of wet chemistry and CPMAS 13C-NMR spectroscopy. “Mollic” in contrast to “Umbric” humusforms could be characterized by a higher carbonyl/carboxyl carbon content probably deriving from proteins, polysaccharides and humic substances. In addition the mollic epipedon contains 10% more litter compounds, whereas in the umbric epipedon humic acids are of major importance. The humin fraction in the mollic epipedon is thought to be raised by the formation of Ca-humates. Our data suggest, that with regard to microbial decomposition a surplus of available organic matter is present in the mollic horizons. The ochric-like epipedon has a much lower humus content compared to “Mollic” and “Umbric” horizons and exhibits the highest amounts of soluble organic matter as well as aromatic and carboxylic C-compounds in the humic fraction. Our data suggest, that SOM quantity and quality of the mollic, umbric and ochric epipedons differ substantially. These findings suggest that the proposal of Schlichting et al. (1995), which was extended by Blume & Beyer (1996), should be regarded as a useful basis to discuss the development of humusforms in soils under cultivation and facilitate soil survey in order to improve site characterization. 相似文献
5.
Mineralization of soil organic matter and of added 14C labelled substrates were studied on samples from two acidic forest soils, “Cademario”-sample from the Bh-horizon of a cryptopodzolic soil rich in humus and nonexchangeable Al and “Sagno”-sample from the A-horizon of a Haplumbrept with moderate humus- and Al-content. The respiration rates for the two soils were not different when related to the content of organic matter. When treated with Na2CO3, the CO2 production rate in the Sagno soil increased about three fold whereas no significant difference was observed for Cademario samples. This is attributed to the more pronounced dissolution of organic matter due to the pH increase in the Sagno soil. N-mineralization was different in the two soils. During a 28 day incubation period, 0.11% and 0.34% of the total organic N was released in the Cademario and Sagno samples, respectively. Na2CO3 treatment stimulated N-mineralization in both soils but the mineral N-form was primarily nitrate in the Sagno sample and ammonium in the aluminum-rich sample from Cademario. Glucose, succinate and salicylate added to the soils were mineralized in this order. However, CO2 evolution was much slower in the case of salicylate, especially in the untreated soils, a fact which is attributed to the Al-complexing power of this substrate. 相似文献
6.
Differences in the properties of soil organic matter as a result of differing soil managements The organic matter of 62 soil samples from 20 farms was analyzed by the following methods: total organic C, “light” C (density < 2 g/ml) and C content and Q 4/6 of extracts obtained with NaF and NaOH solutions under different conditions. The soil samples were obtained from 10 pairs of adjacent plots; in each pair one of the plots was under “conventional”, the other under “bio-dynamic” management. The results obtained by the different laboratory methods evidenced more or less clearly the different managements. C extracted by shaking the soil with 0,5 % NaOH was most significant in that respect. The results as a whole are coherent in showing that in the soils under bio-dynamic treatment of higher content of the more easily decomposable fractions of the organic matter as compared with the soils under conventional treatment can be detected by rather simple means. 相似文献
7.
The retention of dissolved organic matter in soils is mainly attributed to interactions with the clay fraction. Yet, it is unclear to which extent certain clay‐sized soil constituents contribute to the sorption of dissolved organic matter. In order to identify the mineral constituents controlling the sorption of dissolved organic matter, we carried out experiments on bulk samples and differently pretreated clay‐size separates (untreated, organic matter oxidation with H2O2, and organic matter oxidation with H2O2 + extraction of Al and Fe oxides) from subsoil horizons of four Inceptisols and one Alfisol. The untreated clay separates of the subsoils sorbed 85 to 95% of the dissolved organic matter the whole soil sorbed. The sorption of the clay fraction increased when indigenous organic matter was oxidized by H2O2. Subsequent extraction of Al and Fe oxides/hydroxides caused a sharp decrease of the sorption of dissolved organic matter. This indicated that these oxides/hydroxides in the clay fraction were the main sorbents of dissolved organic matter of the investigated soils. Moreover, the coverage of these sorbents with organic matter reduced the amount of binding sites available for further sorption. The non‐expandable layer silicates, which dominated the investigated clay fractions, exhibited a weak sorption of dissolved organic matter. Whole soils and untreated clay fractions favored the sorption of ”︁hydrophobic” dissolved organic matter. The removal of oxides/hydroxides reduced the sorption of the lignin‐derived ”︁hydrophobic” dissolved organic matter onto the remaining layer silicates stronger than that of ”︁hydrophilic” dissolved organic matter. 相似文献
8.
Soil was freed of its organic matter by heating it to 400°C. Plants were grown in a 14CO2 atmosphere and from them a labelled “soil organic matter” (humus) was prepared by composting the plant material for more than 3 yr in the modified soil under laboratory conditions. The influence of small additions of unlabelled glucose on the decomposition of the labelled soil organic matter was studied. Shortly after the addition of glucose there was a small extra evolution of 14CO2, which lasted about 1 day. It is claimed that the extra evolution of 14CO2 was caused by conversion of labelled material in the living biomass and was not due to a real priming action, i.e. an accelerated decomposition of humic substances or dead cellular material. 相似文献
9.
A significant fraction of soil organic carbon, named stable organic carbon (C) pool, has residence times longer than centuries and its vulnerability to land use or climatic changes is virtually unknown. Long-term bare fallows offer a unique opportunity to isolate the stable organic pool of soils and study its properties. We investigated the vulnerability of the stable organic C pool to fresh organic matter inputs by comparing the mineralization in a long-term bare fallow soil with that of an adjacent arable soil, containing stable C as well as more labile C. For this, we amended or not the soil samples with two different 13C-labelled fresh organic matter (straw or cellulose). In all cases we found a positive priming effect (i.e. an increased mineralization of soil organic carbon) when fresh organic matter was added. By comparing the results obtained on both soils, we estimated that half of the “primed” C in the arable soil due to straw addition as fresh organic matter, originated from the stable C pool. Our results suggest that under such conditions, which frequently occur, the stable pool of soil organic matter may largely contribute to soil extra-CO2 emissions due to priming effect. Consequently, the C storage potential of this pool may be modified by changes in land use and/or biomass production that might change the priming of the mineralization of the stable pool of soil organic carbon. 相似文献
10.
Changes in the carbon (C) balance of boreal forest ecosystems may impact the global C cycle and climate. The degree to which antecedent temperature regime and mineral protection of soil organic matter (OM) influence the temperature response of boreal soil C pools remains unknown, however. To investigate these phenomena on time scales relevant to anthropogenic climate change, we quantified the temperature response of four soil C pools (L, F and H organic horizons and B mineral horizon) within soil profiles collected from replicated sites representing two regions along a climate transect (“regional warming”) during a 480-day incubation at 5 and 15 °C (“experimental warming”). We hypothesized that 1) warmer region soils would exhibit reduced bioreactivity, a measure of C lability assessed via cumulative soil C mineralization, relative to colder region soils, paralleling a decrease in bioreactivity with depth in both regions, and 2) temperature sensitivity of C mineralization (denoted as Q10) would increase with decreasing bioreactivity congruent with the “C quality-temperature” (CQT) hypothesis, with a smaller effect in mineral soil where physico-chemical protection likely occurs. Cumulative C mineralization decreased from surface L to deeper horizons and from the cold to warm region for organic F and H horizons only. This decrease in soil bioreactivity with depth was paralleled by an increase in Q10 with depth as expected, except in mineral soil where Q10 was similar to or lower relative to the overlying organic layer. The lower bioreactivity in F and H horizons of the warm relative to the cold region was not, however, associated with a greater Q10. A warmer regional climate in these otherwise similar forests thus resulted in reduced bioreactivity of isolated soil C pools without increasing the temperature sensitivity of soil C mineralization. This suggests that assumptions about temperature sensitivity of C mineralization based on the propensity for isolated organic C pools to undergo mineralization may not be valid in some organic-rich, boreal forest soils. 相似文献
11.
Muhammad Shahid Tiantian Xiong Nasir Masood Tibo Leveque Katelle Quenea Annabelle Austruy Yann Foucault Camille Dumat 《Journal of Soils and Sediments》2014,14(4):655-665
Purpose
The present research aimed to assess the influence of two phosphorous (P) amendments on metal speciation in rhizosphere soil and the soil–plant transfer of metals.Materials and methods
Complementary experiments were performed: field experiments on a contaminated cultivated soil and laboratory experiments on an uncultivated contaminated soil to highlight the mechanisms involved in metal-phosphorous interactions. In laboratory experiment, P amendments were added at 120 mg P/kg of soluble KH2PO4 amendment and 9,000 mg P/kg of solid Ca5(PO4)3OH amendment.Results and discussion
Field-culture results showed the possible food-chain contamination due to Pb, Cd, Cu, and Zn phytoaccumulation by pea and mustard plants from a cultivated agricultural soil. Moreover, P-metal complexes were observed by microscopy in the rhizosphere soil. In laboratory experiments, the application of P amendments significantly increased Pb and Zn level in rhizosphere soil compared to control. Phosphate amendments significantly increased metal-P fraction and decreased “oxides” and “organic matter” fractions of Pb and Zn. Soluble-P amendment was more effective than solid P amendment in changing Pb and Zn speciation. The changes in metal speciation are higher in the rhizosphere soil of pea than tomato. Application of P amendments increased Pb and Zn TF root/soil but decreased TF shoot/root.Conclusions
The effectiveness of in situ metal immobilization technique varies with the type and quantity of applied P amendment as well as plant and metal type. 相似文献12.
Rice is the main crop grown in Japan, approximately three million hectares or half of the total arable land being planted to rice. However, not less than 20 percent of the rice fields is estimated of so called “Akiochi” type, which means autumn-decline in English. It has been observed that these low productive paddy soils may be divided roughly into two types, one of which is the soil of well-drained, so called “degraded” paddy field, and the other is the soil of ill-drained one with too much organic matter, humus, in the soil. 相似文献
13.
《Communications in Soil Science and Plant Analysis》2012,43(19-20):2531-2544
Abstract The clay percentage determined by mechanical means in distilled water without the removal of organic matter and soluble salts and use of a chemical dispersant, is referred to as water dispersible clay (WDC). In this study, a “micro‐pipette” WDC method is developed and described. The method increases laboratory production, i.e., number of samples per day, and yet requires less laboratory space and time. In addition, this method yields, for most soils, WDC values comparable to those values obtained by the standard SCS “macro‐pipette” method. Statistical analysis of variance (ANOVA) for determination of WDC percent indicates nonsignificant effects at α = 0.05 for both method and method times soil but significant effects for method times soil interaction term at α=0.10. In order to characterize the particle‐size distributions, a moment analysis was run on each of the 14 soils. In this study, the distributions of most soils measured by the “macro‐pipette” method are not significantly different by the “micro‐pipette” method. This abbreviated method may represent a significant savings for both high‐volume characterization laboratories and research and developmental work. This application of the measurement of WDC may also be modified for use in the soil survey field office. 相似文献
14.
Kanji Kawai 《Soil Science and Plant Nutrition》2013,59(3):97-103
Andosol is a soil widely distributed throughout Japan and is one of the important soils for the agriculture. The name “Ando soil” was given by THORP and SMITH (19) which means dark soil with an organic matter content ranging up to 30 per cent in the darkest members of the group. In 1964, the Soil Correlation Meeting on Volcanic Ash Soils (8), organized by FAO, adopted “Andosol” for volcanic ash soil of which the active fraction is predominated by amorphous material. Andosol, moreover, has many special properties such as high sorption capacity, high accumulation of organic matter, low bulk density and low stickiness. TAYLOR (18), accordingly, named them “amorphic soils”. The latest soil classification system, 7th Approximation (15) includes andosol under the suborder andepts. 相似文献
15.
The data of long-term studies pertinent to functioning of cyanobacteria and their effects on soil fertility during periods of soil “blossoming” over more than 50% of the soil surface are presented. Parameters of and participants in this process and its features typical for the temperate zone are discussed. Using modern methods of investigations (field 15N2 and 13CO2 chambers, spectral-isotope and gas chromatographic analyses), cyanobacteria were revealed to produce 725 kg/ha. They are characterized by intense photosynthesis inherent to mosses and lichens. The conditions of cyanobacteria functioning in plowed soils are discussed. Their contribution to the nitrogen pool of soils reaches 30 kg/ha. Based on the model experiments, a concept of transforming the organic matter of cyanobacteria in soil and its movement along trophic chains of the biological cycle has been developed. 相似文献
16.
畜禽养殖业的集约化和规模化发展,造成畜禽粪污产生量急剧增加。畜禽粪污处理不当可对周遭的土壤、水体、大气等造成污染,成为我国农业面源污染的主要来源之一。基于Web of Science核心合集数据库,采用文献计量学方法对此研究领域的相关文献进行分析整合。结果表明：(1)全球对粪肥污染研究的重视程度越来越高,沼液作为畜禽粪污厌氧消化的主要产物,其在还田领域的发文主要集中于土壤科学、环境科学、农学3个学科;(2)美国、中国、德国、澳大利亚、法国等国家在沼液还田利用研究领域发文量较多,相互合作密切;(1)沼液还田利用领域的发文期刊主要有Agriculture Ecosystems&Environment、Geoderma、Science of the Total Environment,其中2021年的SCI影响因子较高的主要期刊有Science of the Total Environment、Geoderma、Agriculture Ecosystems&Environment、Catena等。沼液还田利用的未来研究趋势主要集中于沼液所携带的活性物质与菌群对土壤肥力的促进机... 相似文献
17.
Emilie Jardé Gérard Gruau Laurence Mansuy-Huault Pascal Peu José Martinez 《Water, air, and soil pollution》2007,178(1-4):169-178
Samples of pig slurry, as well as dairy and poultry manures collected in Brittany (western France) were analysed to test the ability of sterol profiles to provide a fingerprint of pig slurry contribution to soil organic matter. The data show that the 5β-stanol, known as coprostanol, is the most abundant sterol present in pig slurry, whereas this compound occurs only in minor amounts in both poultry and dairy manures. Moreover, systematic variations of (campesterol + sitosterol)/cholesterol (i.e., C28+29/C27) and (coprostanol + epi-coprostanol)/cholesterol (i.e., 5β/C27) ratios allow to discriminate clearly pig slurry from poultry and dairy manures. The robustness of the pig slurry “sterol fingerprint” was tested by analysing the sterol profiles of soil samples from an experimental field that had received a massive pig slurry input between 10 to 14 years ago. The results indicate that the specific sterol profile of pig slurry is conservative once the slurry has been incorporated into the soil. In particular, the diagnostic 5β/C27 ratio proves to be constant with time in soils having received pig slurry application, even 10 years after the end of the application. The “sterol fingerprint” of pig slurry is thus sufficiently distinctive from dairy and poultry manures, and also sufficiently time-resistant, to be of diagnostic value in determining whether a soil sample was once contaminated by pig slurry. 相似文献
18.
Soil respiration is not limited by reductions in microbial biomass during long-term soil incubations
Declining rates of soil respiration are reliably observed during long-term laboratory incubations. However, the cause of this decline is uncertain. We explored different controls on soil respiration to elucidate the drivers of respiration rate declines during long-term soil incubations. Following a long-term (707 day) incubation (30 °C) of soils from two sites (a cultivated and a forested plot at Kellogg Biological Station, Hickory Corners, MI, USA), soils were significantly depleted of both soil carbon and microbial biomass. To test the ability of these carbon- and biomass-depleted (“incubation-depleted”) soils to respire labile organic matter, we exposed soils to a second, 42 day incubation (30 °C) with and without an addition of plant residues. We controlled for soil carbon and microbial biomass depletion by incubating field fresh (“fresh”) soils with and without an amendment of wheat and corn residues. Although respiration was consistently higher in the fresh versus incubation-depleted soil (2 and 1.2 times higher in the fresh cultivated and fresh forested soil, respectively), the ability to respire substrate did not differ between the fresh and incubation-depleted soils. Further, at the completion of the 42 day incubation, levels of microbial biomass in the incubation-depleted soils remained unchanged, while levels of microbial biomass in the field-fresh soil declined to levels similar to that of the incubation-depleted soils. Extra-cellular enzyme pools in the incubation-depleted soils were sometimes slightly reduced and did not respond to addition of labile substrate and did not limit soil respiration. Our results support the idea that available soil organic matter, rather than a lack microbial biomass and extracellular enzymes, limits soil respiration over the course of long-term incubations. That decomposition of both wheat and corn straw residues did not change after major changes in the soil biomass during extended incubation supports the omission of biomass values from biogeochemical models. 相似文献
19.
《Communications in Soil Science and Plant Analysis》2012,43(17-18):2521-2537
Abstract Many of the cultivated soils of sub‐Saharan Africa typically have a surface horizon low in clay and with a low cation exchange capacity (CEC). In these soils, CEC is largely due to the soil organic matter (SOM). Measurements made on long‐term trials show that changes in CEC and SOM are positively correlated to one another, but not of same magnitude, suggesting that not all of the SOM plays an equal role as regards the soil CEC. To study the influence of the different SOM size fractions on the CEC, soils with or without application of manure or compost coming from trials in Chad and Côte d'Ivoire were separated without destruction of the SOM into five organo‐mineral fractions: “coarse sand”;, “fine sand”;, “coarse silt”;, “fine silt”;, and “clay”; made up of particles of sizes between 2,000 and 200, 200 and 50, 50 and 20, 20 and 2, and 2 and 0 μm, respectively. Fractionation was carried out by mechanical dispersion of the soil, wet sieving of the fractions larger than 20 μm, and decanting of the “clay”; and “fine silt”; fractions. The CEC of these fractions increases inversely with their size. The “clay”; fraction which contains half of the SOM contributes about 80% of the CEC of the soils. The CEC of the fractions is largely a function of their carbon (C) content, but the organic CEC per unit C of the “clay”; fraction appears to be four times greater than that of the other fractions (1,000 as against 270 cmolc kg‐1). Applications of manure or compost increase the CEC of the soils by increasing the soil C only when this C increase concerns the fine fractions of the SOM. 相似文献
20.
A range of potential substrates for ethylene formation was tested and methionine, in combination with glucose as an energy source, was found to give the greatest quantity of the gas. Crop residues provide natural sources of substrates, but no correlation was found between C2H4 production and the amount of combined organic matter (humus) present in the soil after residue application. Soils might be categorized “substrate-rich” or “substrate-deficient” in terms of their capacity to produce C2H4. In soils with small aggregates, C2H4 accumulation is enhanced when gaseous exchange with the atmosphere is inhibited. 相似文献