Development of pollution-neutralizing properties in very young mine soils

Various properties capable of neutralizing environmental pollution (aggregate stability, buffer capacity and ion adsorption capacity) were determined in spoil from a lignite mine in Galicia (northwest Spain) and in mine soils of four and seven years age developed from this spoil. Buffer capacity and the adsorption of copper, cadmium and phosphate increased markedly with soil age, whereas the dispersion ratios of both macro- and micro-aggregates decreased sharply. These changes are attributed to the known increase in organic matter and extractable iron and aluminium. These components aid interparticle binding and create both exchange sites and specific adsorption sites. The ultimate causes are thought to be the successful establishment of an active field plant cover, the considerable colloid content of the parent material, the management of the mine soils and the climatic conditions of the area, which favour both the accumulation of soil organic matter and the weathering of the parent material.     

Evaluation of three organic wastes for reclaiming burnt soils: Improvement in the recovery of vegetation cover and soil fertility in pot experiments

The efficacy of three abundant organic wastes: poultry manure (PM), cattle slurry (CS) and sewage sludge (SS) for the reclamation of burnt soils was evaluated. A forest soil, previously furnace-heated in order to simulate exposure to a high-intensity wildfire, was labelled with nitrogen-15 (¹⁵N) to evaluate the contribution of N derived from the organic waste to the burnt soil and vegetation. Four treatments were performed with the heated ¹⁵N-labelled soil: an unamended control soil (S) and three waste amended soils (S+PM, S+CS and S+SS) at a dose waste of 167mg total N kg^–1 soil. Lolium perenne was grown in all the pots for 3 months. In each treatment the phytomass produced and its N content decreased significantly in the following order of treatments: S+PM S+CS > S+SS S. The percentage of plant N derived from the waste was similar in the S+PM (22.8%) and S+CS (24.0%) treatments, but significantly lower in the S+SS treatment (16.5%). At the end of the 3 month experimental period, the available N reserves (phytomass N+soil inorganic N) in the control soil accounted for 51.5–71.5% of those in the S+PM, S+CS and S+SS treatments, whereas the yield of the plants was only 13.4–29.8% of that in the manured soils. These results demonstrated the importance of the addition of organic wastes, particularly PM, for the recovery of the vegetation cover and for the stabilization of the soil ash layer. They also showed that the level of N was not the main controlling factor of plant growth in the control soil, which, moreover, did not show evidence of a shortage of macronutrients, i.e. phosphorus, potassium, calcium or magnesium. It is hypothesized that, as occurs in heat-sterilized soils, phytomass production in the control-heated soil could have been inhibited by the heat-induced production of phytotoxic compounds, their negative effects being microbially or chemically suppressed by the addition of organic wastes. Received: 3 March 1997     

Amino acids in grassland soils: Climatic effects on concentrations and chirality

The response of soil organic nitrogen (SON) dynamics to climate may partly be deduced from changes in the concentration and origin of the major N constituents in soil, such as amino acids. In this study, we determined the enantiomers of bound amino acids in 18 native grassland soils (0–10 cm) that were sampled along a transect from central Saskatchewan, Canada, to Southern Texas, USA. Mean annual temperature (MAT) ranged from 0.9 to 23.4 °C and mean annual precipitation (MAP) from 300 to 1308 mm. d-alanine and d-glutamic acid served as markers for the bacterial origin of SON. The d-content of lysine, phenylalanine, and aspartic acid indicated an ageing of the respective SON forms. Deuterium labeling was applied to account for hydrolysis-induced racemization reactions. We found that the concentration of the bacterial biomarkers was weakly but significantly parabolically related to MAT, as previously reported for microbial-derived amino sugars. The age markers d-lysine, d-phenylalanine, and d-aspartic acid comprised 2–15% of the respective l-form. The presence of these compounds demonstrated that the structures that contained these d-enantiomers had survived microbial attack, i.e., these hydrolyzable SON forms were conserved in soil despite a living environment. First estimates indicate that the mean residence time of the lysine-containing organic matter forms extend beyond a century. Within this time-scale we did not find that climate significantly affects the degree of ageing of SON constituents in the studied topsoils.     

Development of a capillary electrophoresis–mass spectrometry method for small peptides in the soil solution

Small peptides are being investigated for their role in ecosystem cycling and plant uptake of organic N, but little is known of molecular forms in the soil solution. The aim of this study was to develop a capillary electrophoresis–tandem mass spectrometry procedure for profiling small peptides in the soil solution. Capillary electrophoresis–mass spectrometry was capable of separating and detecting a range of small peptide standards. Adequate recovery (>90%) of standard peptides spiked into samples of soil solution indicated that separation and detection were robust and not significantly affected by the sample matrix. The method was applied to samples of soil solution from grassland mesocosms filled with clay-loam soil from an abruptic lixisol. Soil solution (ultrafiltered <3 kDa) contained at least 298 putatively identified peptides with most being smaller than 600 Da. Less than 5% of small peptides contained basic amino acids, which may reflect their preferential adsorption to the soil stationary phase versus peptides comprised of acid or neutral amino acids. Capillary electrophoresis–mass spectrometry of small peptides is robust and has already yielded novel findings with its first proof of concept measurements on the soil solution.     

不同种植模式下菜地土壤腐殖质组分特性的动态变化

通过在南京普朗克有机农场开展的9年长期定位监测,研究了有机(露地和大棚)和常规种植模式下蔬菜地耕层土壤有机碳和土壤腐殖质组分特性的动态变化。结果表明,有机露地、有机大棚和常规露地种植土壤有机碳含量分别从11.41、9.29、9.00 g k g-1提高至15.35、20.90、10.00 g kg-1;胡敏酸碳(CHA)分别从1.79、1.23、1.14 g kg-1提高至2.11、3.11、1.31 g kg-1;富里酸碳(CFA)分别从2.19、1.88、1.73 g kg-1提高至2.44、2.68、1.91 g kg-1。两种有机种植模式的土壤有机碳及腐殖质组分含量增加达到显著水平,而常规种植模式下的变化不显著。两种有机种植模式下表征土壤腐殖质品质的胡/富比(CHA/CFA)、胡敏酸占总腐殖物质的比例(PQ值)均高于常规种植模式,土壤富里酸的E4/E6值、色调系数(ΔlogK)值随着种植时间增加的幅度较常规种植模式更大,土壤胡敏酸芳化度呈现先降低后增高的趋势,但在常规种植下变化不明显。说明土壤在长期有机种植模式下不仅更有利于土壤有机碳的积累,而且能促进土壤腐殖化进程。     

Temporal variation in pools of amino acids, inorganic and microbial N in a temperate grassland soil

Plants can take up intact amino acids, even in competition with soil microbes, yet we lack detailed information on which amino acids dominate the soil and whether amino acid composition varies seasonally. This study tested the hypotheses that 1) the pool of amino acid N is generally larger than inorganic N; 2) temporal changes in the concentration of amino acid N is related to changes in the size of the microbial N pool; and 3) amino acid N is dominated by simple, neutral amino acids during warm months, whereas during cold months the amino acid N is dominated by more complex aromatic and basic amino acids. Approximately every month for two years we collected soil from a temperate, sub-alpine grassland in the Snowy Mountains of Australia. We quantified exchangeable pools of amino acids, nitrate and ammonium in 1 M KCl extracts. Microbial N was quantified by chloroform fumigation. Averaged across the 21 monthly samples, nitrate was 13% of the quantified pool of soluble non-protein N, ammonium was 34% and amino acid N was 53%. These data are consistent with our hypothesis that the pool of amino acid N is larger than inorganic N. There was substantial variation between months in concentrations of amino acids and inorganic N, but no clear temporal pattern. Microbial N did not vary between months, and thus changes in amino acid N were unrelated to microbial N. Principal components analysis indicated multivariate groupings of the different pools of N that were broadly indicative of function and/or biosynthetic relationships. Thus PCA identified a grouping of aromatic amino acids (Phe and Try) with amino acids derived from oxaloacetate (Asp, Ala, Val, Leu, Ile), and a second group comprising microbial N, nitrate and glycine. The pool of exchangeable amino acid N was dominated by Arg (26% of amino N) Val (20%) Gln (18%), Try (8%) and Asn (8%). Contrary to our hypothesis, the composition of the amino acid pool did not vary in a consistent way between months, and there was no evidence simple amino acids were relatively more abundant in warm months and complex amino acids in cool months.     

林火对土壤有机质的影响研究综述

火干扰被认为地球化学循环和土壤碳循环的主要干扰因素,主要包括森林火灾和计划烧除。就火干扰对土壤有机质的影响进行归纳总结,火干扰对土壤有机质的影响差异很大,主要取决于火灾类型、火强度、火干扰持续时间、可燃物特性、土壤类型、土壤含水率等,高强度火灾后土壤有机质显著减少、腐殖质急剧转化成溶解性物质,火干扰土壤中各粒度级碳含量增加、游离脂肪链的长度有选择性降低、土壤芳香烃和烷基大量增加、土壤腐殖酸与富里酸中的胡敏素数量增加,更高温度下胡敏素是残留在土壤中的主要有机成分,森林可燃物不完全燃烧后经过冷凝形成黑碳;森林火灾直接杀死部分菌类,改变土壤微生物结构和营养成分,通过核磁共振光谱比较腐殖质中的有机化合物,发现火干扰土壤的腐殖质羧基缺位。根据归纳现有研究现状,并提出今后的研究重点与方向。建立火干扰后土壤有机质连续跟踪调查研究机制,土壤有机质变异数据库,加强火干扰对土壤有机质影响机理的模拟研究。     

Structural studies on soil nitrogen by Curie-point pyrolysis — gas chromatography/mass spectrometry with nitrogen-selective detection

Curie-point pyrolysis-gas chromatography mass spectrometry with N-selective detection was used to characterize the structure of organic N compounds in four mineral soils. The technique was found suitable for the fast, sensitive, and highly specific identification of N-containing pyrolysis products from whole soils with total N contents between 0.08 and 0.46%. In order to optimize the methodology, one agricultural soil was pyrolyzed at final temperatures of 573, 773, and 973 K. Almost no chemical alterations to identifiable pyrolysis products were observed when the final pyrolysis temperature was increased from 573 to 973 K. More than 50 N-containing pyrolysis products were identified, and were divided into compound classes chracterized by specific molecular-chemical structures. These included pyrroles, imidazoles, pyrazoles, pyridines, pyrimidines, pyrazines, indoles, quinolines, N derivatives of benzene, alkyl nitriles, and aliphatic amines. Three additional soil samples different in origin and N content were analyzed at 773 K and each showed a specific thermosensitive N-selective chromatogram. Many N-containing pyrolysis products were identified in all samples, which indicated general qualitative regularities in the thermal release of N-containing pyrolysis products from the four soils. In the pyrolyzates of the investigated soils a number of compounds were identified, which is usually not detectable in pyrolysis-gas chromatography spectrometry analyses with N-selective detection of plants and microorganisms. Among these were N derivatives of benzene and long-chain alkyl nitriles, which appear to be soil-specific and suggest significant transformations of organic N in soils. Thus, our results contribute to a better understanding of the molecular-chemical structure of unknown N.     

红原1#泥炭地泥炭性质的初步研究

红原县 1#泥炭地是四川省若尔盖高原泥炭区的优良泥炭矿区之一。对该矿主矿段泥炭的品质作了初步综合考察,测定了泥炭的组成和元素的含量,其质量优于若尔盖地区其他的泥炭矿,具有较高的开发价值。     

Evaluation of the land reclamation project at the As Pontes Mine (NW Spain) in relation to the suitability of the soil for plant growth

The reclamation and monitoring methodologies implemented at the mining waste dump at the As Pontes Lignite Mine in Galicia (NW Spain) are briefly described. In addition the factors affecting achievement of reclamation objectives and an evaluation of the factors limiting plant growth on the constructed soils are outlined. The most serious limitations were found in the oldest mine soils constructed from sulphide-bearing spoils; high acidity, toxicity, nutrient deficiency, seasonal waterlogging due to their impermeability, and compaction. The youngest soils were constructed using sulphide-free spoils as topsoil substitutes and had fewer limitations for plant development. The results show that proper handling of spoils, and paying special attention to selective placement of sulphide bearing materials, are the most important factors in providing a suitable medium for plant growth. © 1998 John Wiley & Sons, Ltd.     

Humus forms in terrestrial ecosystems: a framework to biodiversity

Humus forms are the seat of most biological transformations taking place in terrestrial ecosystems, being at the interface between plants, animals and microbes. The diversity of terrestrial humus forms (mor, moder and mull) can be attributed to the existence of different patterns (strategies) for the capture and use of resources by ecosystems, in ascending order of biodiversity and bioavailability. Arguments are found in the parallel development of humus forms and terrestrial ecosystems, in exclusion mechanisms between organisms living in different humus forms, and in palaeontological studies. The diversification of terrestrial life forms in the course of Earth history, concomitant with an improvement in resource availability due to the development of sedimentary layers at the surface of continents, may explain the successive appearance of more active humus forms enabling the co-existence of an increasing number of organisms. Contradictory reports about the relationships between biodiversity and stability of ecosystems can be explained by the existence of different belowground pathways making ecosystems more stable.     

腐殖质在工业污染场地土壤修复中的应用综述

随着城市化发展和产业结构调整,大量遗留的工业污染场地对生态环境和人类健康构成严重威胁,新的修复技术和修复材料亟待开发,腐殖质作为天然有机材料对污染场地土壤修复的作用已经引起研究人员的广泛关注。综述了土壤腐殖质的结构与性质、分离与纯化方法,在此基础上阐述了腐殖质在工业污染场地土壤修复,特别是有机污染物和重金属修复中的作用,并介绍了腐殖质作为有机修复剂在土壤修复工程实践中的应用现状,最后提出腐殖质在土壤修复中还需要重点研究的方向,以期为腐殖质作为新的工程材料在土壤修复中的开发利用提供理论基础和技术参考。     

Net microbial amino sugar accumulation process in soil as influenced by different plant material inputs

Identifying the impact of plant material inputs on soil amino sugar synthesis may advance our knowledge of microbial transformation processes in soils. In a 12-week laboratory microcosm incubation, 1, 2, 4, and 6% (w/w) soybean leaf or maize stalk were initially added to soil, respectively, whereas soil without plant addition was used as a control. The results showed that adding organic materials to the soil led to a net accumulation of amino sugars, because of greater microbial synthesis. The ratios of glucosamine to galactosamine and of glucosamine to muramic acid, two indicators differentiating the relative contribution to soil organic matter of fungi and bacteria, showed substantial variance across the gradient of substrate addition. Our results suggest that the amount of nutrients in a given substrate is the primary attribute determining microbial net accumulation of soil amino sugars, especially in the relatively short term, whereas the composition of nutrients might be more important in the relatively long term when nutrients are not sufficient. The use of the two ratios (glucosamine to galactosamine and glucosamine to muramic acid) reflects different dynamics of galactosamine and muramic acid during the decomposition of organic substrates in soils. Muramic acid, compared with galactosamine, is more likely to accumulate in the soil active organic fraction under abundant nutrient conditions, whereas it would be decomposed along with active organic matter when the nutrients are scarce and remain in minor quantities in the clay fraction without being attacked by microbes.     

有机物料施用下原生盐碱土胡敏酸结构特征

为研究不同有机物料对原生盐碱土胡敏酸官能团组成的影响,以吉林省大安市原生盐碱地为研究对象,设置空白处理(CK)、颗粒状秸秆处理(KL)、正常玉米秸秆处理(JG)、牧草处理(MC)和羊粪处理(YF),通过红外光谱与主成分分析(Principal component analysis,PCA)相结合,研究不同有机物料施用下土壤胡敏酸红外光谱特征。结果表明,有机物料各处理与CK处理相比增加了土壤胡敏酸中脂肪碳和芳香碳的相对含量,减少了羧基碳的含量。除KL处理外,其他处理均增加了土壤胡敏酸中氨基化合物的相对含量。同时有机物料的施用增加了土壤胡敏酸的脂族碳/羧基碳和脂族碳/芳香碳比值,表征有机物料的施用使得土壤胡敏酸结构缩合度和氧化度下降,脂族性增强,芳香性降低,胡敏酸结构趋于脂族化、简单化、年轻化。对比两种秸秆处理,发现KL处理更有利于土壤新形成结构年轻化、简单化、脂族性强的胡敏酸分子。根据PCA结果,有机物料的施用是土壤中脂族性碳、芳香族碳以及氨基化合物的主要来源之一,为探讨胡敏酸官能团的来源提供依据。通过红外光谱结合PCA,发现了土壤胡敏酸官能团组成对有机物料的不同响应,为研究有机物料的施...     

Amino acid cycling in three cold-temperate forests of the northeastern USA

Amino acids play a critical role in soil-N cycling. Much of the current research on amino acid cycling has been conducted in arctic, alpine, boreal, and temperate grassland ecosystems. There are no comparable data for temperate forests. We quantified the concentration and production of amino acid N and inorganic N in three forests varying in parent material and tree species composition in Connecticut, USA. Soil samples were collected on three sample dates in 2001 and 2002. At all three sites, a pool of free amino acids was present in soil on all sample dates. Among-site differences in the production of amino acids were related to variations in the activity of proteolytic enzymes, the sensitivity of proteolytic enzymes to the availability of protein substrate, and the presence or absence of a surface organic horizon. Among-site differences in amino acid turnover appeared to be at least partially related to soil C-to-N ratios and their effect on C vs. N limitation to microbial function. Amino acid concentrations in the top 15 cm of mineral soil in these study sites fell within the range of reported values for ecosystems spanning a wide latitudinal gradient, including ecosystems in which amino acids are thought to contribute substantively to plant-N nutrition. The concentration of amino acid N in the organic horizons of these study sites was considerably higher than those reported in the literature. The implications of the results for N capture by temperate forest trees are discussed.     

The effect of lime and fertilizers on four lignite overburdens under non‐drained conditions: I. Yield and nutrient concentration of common bermudagrass.

Abstract

Common bermudagrass (Cynodon dactylon (L.) Pers.) was grown on four different overburdens from the potential lignite mining area of Louisiana. A pot study was conducted in the greenhouse to evaluate the fertility status of the overburdens for future recommendations of fertilizers and soil amendments during the revegetation of the reconstructed soil.

Fertilizer at the rate of 0, 1/2>x, 1x, 2x and 4x the soil test recommended rate of N, P and K for common bermudagrass were applied to the materials. Lime was applied to the Cow Bayou formation material to raise the pH to 6.5. Bermudagrass forage was harvested every six weeks over a 24 week period to evaluate dry matter yield and mineral composition.

Yield and nutrient uptake (N, P, K, Ca, Mg, S, Fe, Mn, Zn, and Cu) were significantly (α = 1%) affected by increasing rates Df fertilizer in all overburden materials except P uptake in the Cow Bayou material. In general, yield and nutrient uptake increased with each addition of fertilizer. Total yield was not significantly (α = 1%) different when the recommended rate of N, P and K fertilizer was applied in all overburdens. However, total yield was highest in the Prairie Terrace and Dolet Hills overburdens when 4x this rate was applied. Nutrient concentration was not significantly affected by fertilizer application except for N in the Naborton material, Ca in Prairie Terrace and Naborton, S in Dolet Hills and Zn in Prairie Terrace and Naborton (α = 5%).     

模拟酸雨胁迫对赤红壤磷素形态特征的影响

通过田间小区模拟酸雨实验,研究酸雨胁迫下赤红壤不同磷素形态变化的方向和程度。结果表明,原位模拟酸雨影响下,一定强度（pH≥4.0）的酸雨胁迫能有效促进有效磷的释放,而当pH〈4.0强度酸雨胁迫时有效磷的释放随pH值降低逐渐受到抑制。随酸雨酸度的增强,土壤酸性磷酸酶和微生物量磷均呈现先升高后降低的变化趋势,可见一定强度酸雨胁迫能促进溶磷微生物和磷酸酶活性,而当高强度酸雨胁迫时土壤微生物活动逐渐受到抑制。无机磷组分中Al-P、Ca-P和Fe-P含量均随酸雨酸度的增强而降低,土壤O-P含量没有显著变化。相关分析发现,有效磷含量与微生物量磷、酸性磷酸酶呈极显著正相关,表明此时土壤有效磷变化与有机磷矿化关系最为密切。有效磷含量与各种形态无机磷（Al-P、O-P、Ca-P和Fe-P）含量之间也有较强的正相关性,表明土壤生态系统磷素转化是一个自我调节的动态平衡过程,且在一定条件下可以相互转化。