增温与干旱双重变化对若尔盖泥炭CH4排放的影响

若尔盖泥炭地经历了长期人为排水,未来又面临着强烈的变暖干旱,会对泥炭地CH₄排放产生复杂影响。在若尔盖选取了近自然和长期人为排水两种泥炭地类型,采集1 m深泥炭柱,采用室内环境控制试验,设定不同的氧气、水分和温度条件,探索这两种典型泥炭地的泥炭CH₄排放对增温与干旱双重变化的响应差异。结果表明:(1)由于水位降低和泥炭有机物质量下降,长期排水泥炭地的中下层泥炭(20—80 cm)CH₄累积排放量显著低于近自然泥炭地。(2)两种泥炭地的表层和深层泥炭CH₄排放都对升温不敏感,而中下层泥炭的CH₄累积排放量从5℃到15℃显著增加。(3)模拟增温10℃同时干旱水位降低20 cm条件下,中层泥炭受到了温度、水分和氧气变化的叠加影响,CH₄排放变化最剧烈。(4)最终整个1 m深泥炭近自然泥炭地高温低水位的CH₄总排放量为(204.29±15.13)μg/gC,比其低温高水位显著升高66.43 μg/gC(约48%); 排水泥炭地高温低水位的CH₄总排放量为(75.64±9.41)μg/gC,比其低温高水位升高11.95 μg/gC(约19%)。综上,升温干旱气候会对若尔盖泥炭地的有机碳稳定性造成破坏性影响,会集中导致中层泥炭CH₄排放的剧烈变化,可能最终使本区域CH₄排放量显著提高。     

七姊妹山自然保护区泥炭藓湿地剖面特征及元素垂直分布规律

泥炭藓湿地是由适应能力强、耐周期性干旱的泥炭藓(Sphagnum)以及草本植物沼泽化形成的一种十分重要的湿地类型,也是一种重要的自然资源,多分布于湿润多雨的地区[1]。泥炭藓湿地在我国主要集中分布于松嫩平原、三江平原和若尔盖高原[2]。在亚热带山地,由于受水热条件的限制,泥炭藓湿地有小面积分布。2005年对湖北省七姊妹山国家级自然保护区的科学考察中发现了面积约300hm2的呈斑块状分布的亚热带亚高山泥炭藓湿地,其发现为鄂西山地古地质、古气候及植被变迁研究提供了珍贵的研究样本。目前国内外关于泥炭藓湿地的研究主要集中在湿地植被研究、泥炭元素分析、泥炭种子和孢粉构成分析、泥炭对古气候及古环境的反映、     

国内外泥炭农用特性比较研究

比较研究国内外商品泥炭农用物理化学特性结果表明 ,与国外泥炭相比 ,国产泥炭总孔隙度小 ,容重、灰分含量、pH值和电导率均高 ,阳离子代换量低 ;国产泥炭全量养分含量较高 ,全N、全P、全K分别约为进口泥炭的2倍、3～ 4倍和 3～ 5倍。国产泥炭与进口泥炭相比微量元素全Fe和全Mn含量差异最大 ;除速效铁外国产泥炭其他速效养分与进口泥炭相比差异较小 ,而调试好 pH值的进口泥炭速效钙含量较高。     

试论泥炭的应用分类

泥炭是一种重要的肥料资源。近年来,全国各地普遍开展了挖掘泥炭,制造腐殖酸类肥料的群众运动。在实践过程中,这种泥炭腐殖酸类肥料在提高土壤肥力,增加作物产量等方面,显示了一定的效果。     

泥炭在水土保持中的应用

泥炭具有独特的物理化学性质,是天然的土壤改良剂。本文综述将泥炭应用于水土保持治理,在改善水土流失、土壤沙化、土质退化、降低土壤污染等方面的作用和意义,鉴于泥炭所具有的优良特性以及我国水土保持的严峻形势,寻求泥炭在水土保持领域的新发展。     

泥炭pH的调节试验研究

针对无土栽培中使用的泥炭酸性较强,不适合绝大多数花卉生长这一特点,通过在泥炭中加入不同粒径的白云质石灰石,在25℃±3℃的恒温培养箱中进行培养,测定泥炭pH的变化,从而研究白云质石灰石对泥炭pH调节的效果及pH与石粉粒径的关系。结果表明,泥炭的pH变化主要发生在前5天,到15天后基本达到稳定状态。并且当石灰石粉的粒径为A:Φ<0.01mm时,泥炭的pHH2O为6.00,pHKCl为5.80,达到了比较适合花卉生长的范围。     

汞在泥炭上的吸附动力学研究

采用批次法研究了汞在三江平原泥炭和吉林双阳泥炭上的吸附动力学特征及温度、pH值对吸附的影响,实验表明:在相同的实验条件下,三江平原泥炭对汞的吸附速率小于吉林双阳泥炭;温度升高加快泥炭吸附汞的反应速度;两种泥炭对汞的吸附速率受pH值的影响明显且都在pH6.0左右具有最大的吸附量;在酸性介质内,介质的pH值升高,利于泥炭对汞的吸附;两种泥炭对汞的吸附动力学用Hill方程描述最为合适。湿地泥炭土壤较高的吸附容量,以及湿地低温和适当的pH都利于湿地对汞的累积。     

汞在泥炭上的吸附特征研究

采用批次法研究了汞在三江平原泥炭、吉林双阳泥炭上等温吸附特征及介质pH值、背景离子浓度的影响。实验结果表明:两种泥炭吸附等温线均同时符合Langmuir和Freundlich等温吸附方程,而与Langmuir方程的拟合效果更好; 在溶液汞浓度相同时,温度升高,泥炭对汞的吸附量降低;在相同的条件下,三江平原泥炭对汞的吸附量大于吉林双阳泥炭对汞的吸附量;两种泥炭对汞的吸附量受pH值的影响明显且都在pH 6.0左右具有最大的吸附量;在酸性条件下,吸附介质的pH值升高利于泥炭对汞的吸附;介质的离子浓度升高,可以使两种泥炭对汞的吸附量迅速降低。     

改性泥炭对滨海盐渍土的改良作用研究

采用土培的方法,通过泥炭改性处理,研究不同泥炭对滨海盐渍土物理、化学、生物性质的影响,为滨海盐渍土快速改良提供理论依据。研究结果表明:碱改性泥炭的红外图谱特征与原始泥炭相似,但酸改性泥炭在1 710 cm–1处具有明显的特征峰;扫描电镜下,碱改性泥炭颗粒突起最少,表明碱改性泥炭质地相对均一。碱改性泥炭能够显著降低土壤p H,增加土壤团聚体;而原始泥炭提升土壤有机质和增加碱解氮含量方面效果更加明显。碱改性泥炭和原始泥炭均能够提升土壤酶活性,但酸改性泥炭对土壤酶活性存在抑制作用。相关分析结果表明,土壤p H、有效磷、速效钾与过氧化氢酶、蔗糖酶和纤维素酶的活性具有显著相关性(P0.05)。综上所述,在本次试验中,碱改性泥炭对滨海盐渍土改良作用最佳,添加改性泥炭能更有效地消减滨海盐渍土盐、碱、瘦、板、活力差等障碍因子。     

亦论泥炭的应用分类-就泥炭的应用分类问题与郑应顺等同志商榷

从七十年代开始,我国在农业上就大量利用泥炭制做腐殖酸肥料;在工业上,也开展了应用泥炭的试验研究工作.在实践中,急需要一套适用于生产领域的应用分类,以利泥炭的合理利用.郑应顺等同志1980年2月在本刊发表的《试论泥炭的应用分类》(以下简称《试论》),是我国第一篇专门论述泥炭应用分类的文章,是值得欢迎的.     

THE IMPREGNATION OF WET PEAT FOR THE PRODUCTION OF THIN SECTIONS

A technique is described to replace the water in peat by acetone prior to impregnation with resin. The peat is exposed to the vapour of aqueous acetone of increasing concentration up to 100 per cent acetone. After impregnation with resin, high quality thin sections can be obtained.     

三江平原泥炭资源及其利用

三江平原(包括穆稜—兴凯平原)位于我国的东北部,是黑龙江、乌苏里江和松花江汇流的三角地带,是由沼泽、草甸、森林、河流、湖泊和农田组成的一个巨大的湿生生态系统的低湿平原,是我国重要商品粮基地之一。这里蕴藏着丰富的泥炭资源,合理地开发利用这些泥炭资源,对改良和培肥土壤,建设高产稳产农田和提高作物产量有重要意义。     

EVALUATION OF ORGANIC SOLID WASTES COMPOSTS AS PEAT SUBSTITUTES FOR SEEDLING PRODUCTION

This research work was performed to investigate the possibility of using composted herb residues (C1), co-composted sewage sludge with sawdust (C2), co-composted pig manure with sawdust (C3), and co-composted pig manure with spent mushroom (C4) in the production of horticultural seedlings to replace part of peat in the growing media. The proportions of each compost in the mixtures elaborated with peat were 50%, 75%, and 100% (v/v), respectively. The substrate of 100% commercial peat was used as the control. First, some physical, physical-chemical, and chemical properties of these substrates were determined. Second, four kinds of plants tomato, cucumber, bermudagrass, and impatiens were used to evaluate the possibility of different composts to replace part of peat. The seed germination rate, fresh weight and nutrient concentrations of seedling were then measured. We found that the physical, physical-chemical and chemical properties of these substrates were statistically influenced by the type and the proportion of compost in the substrates. The substrates elaborated with C1 and C2 showed adequate physical and chemical properties for their use as substrate in horticultural seedlings production. The highest germination of cucumber, tomato, bermudagrass and impatiens all occurred at C1 based substrate. Seedling grown in the C1 and C2 based substrate reached better growth and nutrition than peat. Our results suggested that the C1 and C2 were good alternative to peat-based substrate for seedling production, especially at the rate of 75% and 100% of C1 and 50% of C2, which have shown beneficial effects on the seedling production of cucumber, tomato, bermudagrass and impatiens compared to the control. However, C3 and C4 were not always adequately used in substituting expensive peat.     

THE COMPLEXING OF COPPER BY HUMIFIED ORGANIC MATTER FROM LABORATORY PREPARATIONS, SOIL AND PEAT

The metal complexing properties of the colloidal and non-colloidal fractions of water extracts of peat and aerobically composted lucerne, and of chelating resin and alkali extracts of peat and soil organic matter were compared. The contributions of the non-colloidal fractions to the complexing properties of the whole extracts are considerable, and on a weight-for-weight basis are somewhat greater than that of the corresponding colloidal material. No one compound is preponderantly responsible for the complexing action. The complexing activity of the non-colloidal fractions is confined almost entirely to the acidic constituents. On the basis of the enhancement of the visible range of optical absorbance of the various preparations, Cu²⁺ is more extensively complexed than Mg²⁺, Mn²⁺, Cd²⁺, Zn²⁺, Co²⁺, Ni²⁺, and Pb²⁺.     

PEAT WASTAGE IN THE EAST ANGLIAN FENS

Measurements of the decline in peat depth between 1941 and 1971 were taken at 14 sites across the East Anglian Fens. Rates of wastage in the period before 1955 and in the more recent period varied widely from site to site. Wastage rates were higher at all sites but one, in the period before 1955. The mean value for wastage rate over the entire period covered was 1.37 (± 0.78) cm/yr.     

THE PRESERVATION OF PEAT MONOLITHS FOR PERMANENT DISPLAY

Techniques for preparation and preservation of peat soil monoliths for display purposes are described. Impregnation with a low molecular weight polyethylene glycol polymer has been found to be extremely effective in stabilising the natural structural features of peats.     

The Potential for Waste‐Derived Materials to Form Soil Covers for the Restoration of Mine Tailings in Ireland

Revegetation of mine tailings sites can require significant amounts of topsoil, the sourcing of which can be costly and have detrimental impacts. To address this problem at an Irish mine tailings site, engineered soils were created by mixing varying rates of glacial till with stockpiled peat and compost. Soil status was assessed using a range of soil parameters and vegetation growth characteristics and compared with locally sourced topsoil. Hordeum vulgare (Barley) germination and growth trials were assessed on engineered soils: compost with glacial till, peat with glacial till, compost/ peat with glacial till and topsoil. A range of soil quality parameters were examined including: nutrient status, dehydrogenase activity, metals availability and physical characteristics (bulk/particle density and porosity). Results demonstrate that compost derived soils yielded superior plant biomass and nutrient content, whilst peat derived treatments exhibited nutrient deficiency. Whilst the engineered soils offer potential as an alternative to sourcing topsoil for covering mine tailings, the phosphorus and metal content of composts should be assessed prior to inclusion. Copyright © 2015 John Wiley & Sons, Ltd.     

CHANGES IN THE PHYSICAL AND CHEMICAL PROPERTIES OF A MINERAL TOPSOIL UNDER THE INFLUENCE OF PEAT DEBRIS

Changes are reported of particle size distribution, organic carbon and nitrogen values, cation exchange capacity and exchangeable cation populations, and in iron and aluminium patterns as a result of adding varying rates of acid peat debris to a mineral topsoil. Up to 3 cm of peat had beneficial effects on soil chemical and physical properties but 5 to 8 cm was sufficient to cause considerable acidification, release of Fe and other ions from primary minerals and the development of an iron seam (or pan) which contains up to 7 per cent free iron. Greater thickness of peat (up to 30 cm) caused soil reaction to drop to pH 4 or less and produced so much humic acids as to inhibit iron precipitation and to facilitate its removal from the profiles. The effects of soil moisture on the pattern of peat humification in the deeper additions (20–30 cm) are also outlined.