云南省土壤和植物性饲料中矿质元素含量及相关性研究

对云南省家畜饲养基地所属的6个主要地质背景区的土壤和饲料样品的钾，钠，镁、铜，锌、锰、钴，铁、硒和碘元紊进行测定分析．并进行了相关性统计，结果表明：玄武岩红壤区（Ⅴ）和碳酸岩盐红壤区（Ⅰ）土壤各种矿质元素都比较高；其次是碳酸岩盐、碎屑岩和玄武岩混合型黄红壤区（Ⅱ），除了钴较低外，其它元素含量都居中等或偏上水平；而碎屑岩紫色土区（Ⅲ）、变质岩赤红壤区（Ⅵ）和碎屑岩黄红壤区（Ⅳ）大多数矿质养分相对都比较低。大多数饲料中钴、铁和硒的含量受土壤中元素的丰度影响较大；其次为铜、镁、锰、锌和钾；饲料中碘受土壤碘含量影响最小。土壤和各主要饲料间铁、钴、镁、硒和铜相关性较强。     

云南省主要地质背景区钴、铁和硒在岩石—土壤—饲料中的分布与转移规律研究

对云南省反刍家畜主要生产基地所属的6个地质背景区的土壤、岩石和饲料样品的钴、铁和硒元素进行测定分析。结果表明:土壤和饲料钴、铁和硒元素含量在玄武岩(Ⅴ)和碳酸岩盐红壤区(Ⅰ)较丰富;碳酸岩盐、碎屑岩和玄武岩混合型黄红壤区(Ⅱ)居中;而由碎屑岩(Ⅲ)和变质岩(Ⅵ)发育的土壤区土壤和饲料钴、铁和硒元素最低。饲料中钴、铁和硒的含量受地质背景值,特别是土壤中元素的丰度的影响较大。     

云南省主要地质背景区铜、锰、锌、镁、钾在岩石-土壤-饲料系统的分布与迁移规律研究

对云南省6个主要地质背景区的土壤、岩石和饲料样品的铜、锰、锌、镁和钾元素进行测定分析。结果表明:玄武岩和碳酸盐岩红壤区土壤和饲料钾、镁、锌、锰和铜元素含量较丰富;碳酸盐岩、碎屑岩和玄武岩混合型黄红壤区居中;而由碎屑岩和变质岩发育的土壤区土壤和饲料钾、镁、锌、锰和铜元素最低。饲料中钾、镁、锌、锰和铜的含量受地质背景值,特别是土壤中元素的丰度的影响不大。     

京东板栗主产区土壤元素背景值及其影响因素分析

以京东板栗主产区迁西县为研究区域,对土壤中20种植物必需和有益营养元素的背景值及影响元素背景值分布的主要因素进行了分析。结果表明,迁西县土壤中Mg、Fe、Cu、Na、Co和Ni的含量相对富集,而Ca、S、B、Mo和Se的含量相对贫乏,P、K、Ca、Mo和Ni在全县水平范围内的变异性较大。进一步分析发现,成土母质类型是影响矿质元素背景值含量及分布的最基本和最主要的因素,土壤质地、土壤类型和有机质含量是影响背景值的重要因素,而海拔高度对其影响较小。     

中南地区几种土壤的表面电荷特性Ⅲ.土壤的电荷量,电荷零点(PZC)和净电荷零点(PZNC)

研究了中南地区3种土壤的电荷量、电荷零点(PZC)和净电荷零点(PZNC)等表面电荷性质及其与土壤矿质组成的关系.结果表明:(1)从赤红壤、红壤到黄棕壤,永久负电荷量(CECp)趋于增大,主要与土壤的粘土矿物组成和粘粒含量有关;可变负电荷量(CECv)变异趋势不明显,主要与土壤氧化铁铝的组成及含量有关;可变负电荷量占负电荷总量的比例趋于降低;正电荷量趋于减小.(2)供试赤红壤、红壤和黄棕壤的PZC分别为3.90、3.35～3.50和2.96～3.12;赤红壤和红壤的PZNC分别为3.85和2.15～2.84,黄棕壤不存在PZNC.(3)初步提出可变电荷土壤表面电荷性质的指标为:PZC>3.0、PZNC>2.0、PZC朠ZNC<1.0和CECv/CEC8.2>0.4.     

高温高压间歇灭菌对中国典型土壤性质的影响

以中国8种典型土壤(砂质潮土、壤质潮土、黄泥土、乌栅土、红壤、红黏土、赤红壤和砖红壤)为代表,首先比较土壤高温高压间歇灭菌前后细菌、真菌、放线菌的数量,以评估灭菌效果,其次评价灭菌前后主要土壤性质的变化,包括土壤有机质(OM)、比表面积(SSA)、pH、阳离子交换量(CEC)、游离铁铝氧化物(Fed、Ald)、电荷零点(ZPC)。结果表明,该方法可以达到理想的灭菌效果,对部分理化性质则会造成一定的影响。除砂质潮土和红壤高温高压灭菌后OM含量显著增加外,其他6种土壤的OM含量受该灭菌方法的影响不大;酸性和有机质含量高的土壤,pH受高温高压灭菌影响较大,而碱性和有机质含量低的土壤则影响不大;所有供试土壤的SSA均显著降低,而CEC和Fed,Ald没有显著变化;4种可变电荷土壤中,红黏土、赤红壤和砖红壤的电荷零点(ZPC)没有变化,而红壤的ZPC则显著降低,且未出现于本研究测定的pH范围内(pH2.5~8)。由于土壤是一个复杂的多物质体系,受高温高压灭菌导致其性质变化还有待进一步的研究。     

广东省土壤无机元素背景值的变化趋势研究

通过对“七五”期间广东省土壤环境背景监测点回顾性调查,以研究广东省土壤背景监测点13种无机元素含量变化趋势.与“七五”背景值对比,土壤A层中Hg以及A、C两层中F含量下降,其他11种元素含量均上升,特别是Se、V、Zn和Co的含量有较明显的上升.As、Co、Cr、F、Hg、Mn、Ni、V和Zn的含量从A层到C层呈增加趋势,Cd、Pb和Cu的含量呈减少趋势,Se的含量基本没有变化,此外还对无机元素含量变化的原因进行分析.     

不同母质发育土壤的中红外吸收光谱特征

选取湘东丘陵区四种典型母质发育土壤(酸性紫色土、花岗岩红壤、板岩红壤和第四纪红土红壤),采集剖面(深至母岩/母质层)样品,应用傅里叶变换红外光谱仪研究灼烧去除有机质处理、土层深度和母质类型对土壤中红外吸收光谱特征的影响,分析吸收光谱与土壤理化性质的关系。结果表明,去除有机质后,特征区的中红外吸收值升高,反映矿物质对红外吸收谱线的强烈影响。在剖面上,底土(60~80 cm或100~120 cm)的中红外吸收值高于表土(0~20 cm),与土壤有机质含量的剖面分布相反。四种土壤的中红外光谱均属典型的高岭石图谱。砂粒、粘粒含量与红外吸收值的相关性最好,砂粒含量的最大相关系数(0.51)出现在3700、913和720~540 cm~(-1)附近,粘粒含量的最大相关系数(0.54)出现在1100~694 cm~(-1);本研究表明,原土的中红外吸收光谱特征主要受矿物质的支配,可以很好地反映土壤质地的状况,指示土壤质量变化。     

攀枝花芒果幼果黑心病与土壤理化性状相关性分析

为明确芒果幼果黑心病发生与土壤理化性状的关系,比较黑心和正常幼果矿质营养含量差异,调查幼果黑心病果园土壤pH值和养分丰缺情况,并采用相关分析、逐步回归分析和通径分析方法,对发病果园的土壤pH值、土壤养分和幼果黑心病率进行统计分析。结果表明:黑心病果的矿质养分氮、钾、磷、镁和锌含量均显著高于正常果,其他矿质元素含量差异不显著;不同黑心病果园土壤pH值、养分的变异系数和丰缺差异较大,近半数果园土壤pH值不适宜芒果生长,土壤有机质严重偏低、交换性镁和有效铁含量偏高;幼果黑心病率与土壤pH值和有效硼显著负相关,与土壤碱解氮和有机质分别达显著和极显著正相关,与其他土壤养分差异不显著,筛选出pH值(x_1)、有机质(x_2)、交换性镁(x_7)及有效硼(x_(13)),对幼果黑心病率(y)的最优回归方程达到极显著水平;土壤pH值、交换性镁和有效硼对幼果黑心病率影响主要由其直接作用决定,有机质对幼果黑心病率的影响主要由其直接作用和通过pH值间接作用决定。芒果园的土壤酸碱和个别养分丰缺导致幼果矿质元素含量失衡,进而引起幼果黑心病发生,建议通过改良种植土壤和幼果期叶面喷施硼肥等措施防治该病发生。     

丘陵红壤蔗区土壤有机质的时空变异特征

采用地统计学和GIS相结合的方法，研究了甘蔗连作19年(1980～1999年)的低丘陵红壤蔗区土壤有机质含量的时空变异特征。研究结果表明：由于土壤侵蚀和土地利用格局的影响，1980年的土壤有机质与地形坡度为极显著负相关。在长期甘蔗连作下，地形坡度对1999年的土壤有机质空间分布已没有影响，而有机肥施用的侧重方向使得土壤有机质与经纬度、海拔高度都有相关性。土壤有机质的时空变异与蔗区耕作管理的精细化程度有关，精细化程度高的高产蔗区的土壤有机质平均降幅为11％，而精细化程度低的低产蔗区土壤有机质则平均增幅为50％。大量施用源自甘蔗的有机肥已造成蔗区土壤养分的不平衡。     

贵州草海耕地土壤与农作物中DDTs和HCHs残留及污染特征

采集草海流域周边成熟期整株农作物及土壤样品,分析测试其中DDTs和HCHs的含量,对比研究了土壤和作物中DDTs和HCHs污染水平及其在作物中富集能力。结果表明：研究区域土壤中HCHs和DDTs残留检出率均为100％,残留范围分别为0．06～16．66μg·kg^-1和0．08-39．77μg·kg^-1,土壤中HCHs和DDTs的残留量均小于国家土壤环境质量一级标准;三种农作物中DDTs、HCHs及∑（DDTs,HCHs）残留量差异显著,HCHs含量最高的是玉米,DDTs和（DDTs,HCHs）最高的是马铃薯;三种农作物中HCHs和DDTs残留的风险系数均为1．1,属于低度风险,农作物中DDTs、HCHs及∑（DDTs,HCHs）的安全指数IFSc均小于1,DDTs和HCHs残留量对三种农作物安全影响的风险是可以接受的。     

我国亚热带山地丘陵区特征及开发中的有关问题

我国亚热带山地丘陵区，山多地少、人口众多、经济基础薄弱，生态环境严重恶化，障碍着区内经济的发展，区内开发应按照以下几个方面搞好：１、协调山－林－地－人的关系；２．调整粮食－林牧－融渔关系；３．改善生产－生活－生态环境。４．提高生态－经济－社会效益。     

红薯对Pb、Cd的吸收累积特征及根际土壤Pb、Cd形态分布研究

为了解土壤在Pb、Cd单一以及复合污染条件下红薯对Pb、Cd的吸收和积累规律,通过盆栽试验对红薯地上部和地下部的生物量和重金属含量进行测定,分析了单一及复合污染土壤中重金属Pb、Cd形态分布特点。结果表明,相对于对照,较低浓度的Pb、Cd能显著促进红薯的生长（P〈0.05）,Pb超过50mg.kg-1、Cd超过3mg.kg-1时,红薯生长受到显著抑制（P〈0.05）,Cd是影响红薯生长的主要因素;随着试验处理浓度的升高,红薯体内重金属含量也随之升高,二者之间存在极显著的相关性（P〈0.01）,Pb、Cd共存对红薯吸收累积Pb、Cd具有明显的交互作用,Pb促进Cd向地上部转移,Cd促进Pb在地下部积累。根际土壤中Pb、Cd以可交换态与碳酸盐结合态为主,二者均占总量的55以上,在复合污染条件下,Pb浓度为50mg.kg-1时其活性系数显著高于其他Pb处理（P〈0.05）,并在很大程度上促进有效态Cd含量的增加。     

百菌清和毒死蜱在大棚番茄中的分布与降解特征

大棚和露地环境下,分别对番茄植株一次性喷洒推荐剂量的百菌清（CHT）和毒死蜱（CHP）,研究喷药后两周内农药在番茄根、茎、叶和果实中分布的持久性及其动态降解规律。实验结果表明,百菌清在大棚番茄中的残留浓度分布呈现为叶片垌果实〉茎〉根;毒死蜱呈现为叶片〉果实垌茎〉根。大棚番茄各部位的最高残留浓度出现时间滞后于喷药时间8~60h;空间浓度分布上表现为大棚中间区域浓度高于两侧,这与棚内的空气对流有关。大棚番茄果实中百菌清和毒死蜱的残留半衰期分别为5.8d和7.2d,明显高于文献报道。     

Sources of sulphate and acidity in wetlands and lakes in Nova Scotia

There is a declining gradient of wet SO₄ deposition from south to north in Nova Scotia with the highest values being in the south, along with a localized increase around the Halifax metropolitan area, due to local SO₄ emission. Edaphic conditions such as drainage from soils containing gypsum or drainage on disturbed rocks containing pyrite, provide additional SO₄ to surface waters.Acidity is usually absent in the former (pH > 7.0) and very high in the latter (as low as pH 3.6). By contrast peaty, organic drainages release water low in SO₄ during the growing season but they release high amounts of organic anions (A?), consequently, these waters maintain decreased pH values, usually < 4.5. A study of over 80 wetlands and lakes during the ice free period in Nova Scotia showed that sea salt corrected SO₄ concentrations range from 45 ueq L^?1 in the south end of the province, ～30 ueq L^?1 in the Kejimkujik area and < 17 ueq L^?1 in the northern areas with values > 85 ueq L^?1 in the Halifax area, reflecting the atmospheric deposition pattern of SO₄ The SO₄ concentrations may be > 2000 ueq L^?1 in drainages containing gypsum, > 700 ueq L^?1 in drainages over pyrite bearing socks but < 20 ueq/L^?1 in streams draining bogs. The SO₄ concentrations change considerably during the non-growing season when the ground is saturated with water or frozen, and the runoff is high (snow and rain often alternate in winter). Under such conditions SO₄ concentration drops in the two former cases and increases in bog drainages, accompanied with a considerable drop in (A?) concentrations. Care should be taken when interpreting SO₄ concentrations in surface waters in Nova Scotia with respect to atmospheric SO₄ deposition.     

Degradation and development of peatlands in Peninsular Malaysia and in the islands of Sumatra and Borneo since 1990

In this study, we investigated the extent of peatland degradation and development in Peninsular Malaysia and in the islands of Sumatra and Borneo, in the western part of insular Southeast Asia, since 1990. Furthermore, carbon emissions caused by these land cover changes were estimated in order to evaluate their contribution to global climate change. High resolution Landsat (30 m spatial resolution) and Satellite Pour l'Observation de la Terre (SPOT; 10–20 m) satellite images were used to derive information on land cover in 1990 and 2008. Analysis of land cover changes since 1990 revealed remarkable reduction and degradation of peatswamp forest ecosystems. In less than 20 years, 5·1 Mha of the total 15·5 Mha of peatland had been deforested (11·6 Mha → 6·5 Mha; 75 per cent → 42 per cent) and the great majority of the remaining forests had been selectively logged. Simultaneously, area covered by unmanaged secondary growth ecosystems had doubled to nearly a quarter of all peatlands and industrial plantations had expanded dramatically (0·3 Mha → 2·3 Mha; 2 per cent → 15 per cent). It was conservatively estimated that these changes have caused minimum of 1·5 Gt carbon emissions into the atmosphere since 1990. Currently, peatlands of the study area emit at least 81 Mt of carbon (equivalent to 300 Mt of carbon dioxide) on annual basis due to mere peat decomposition. Thereby, it was concluded that peatland degradation and development in insular Southeast Asia during the past two decades have not only put the existence of Southeast Asian peatswamp forest ecosystems in danger but it has also caused globally significant carbon emissions and created a constant source of carbon dioxide. Copyright © 2010 John Wiley & Sons, Ltd.     

Immobilization and species of heavy metals in soils in the absence and presence of rhizobia

Abstract

The effect of bacterial inoculation of Rhizobium fredii HN01 on the immobilization and speciation of Cu, Zn, and Cd was studied in Red and Cinnamon soil which are typical Chinese soils. The soil was mixed with bacterial suspension for one week followed by an immobilization of each heavy metal for another week. The total binding and fractionation of heavy metals in soils were analyzed. As compared with the control, the retention of total Cu, Zn, and Cd in Red soil increased by 28, 16, and 28%, respectively, in the presence of rhizobia. The amount of exchangeable, NH₄OAc-extractable, Mn oxides-bound and organic matter-bound Cu increased by 23–123%. There were significant decrease of exchangeable Cu and marked increases of NH₄OAc-extractable and Mn oxide-bound Cu in Cinnamon soil with the presence of rhizobial cells, although no changes for the total retention of Cu were observed. The amount of exchangeable Zn in Red soil-rhizobia composite was 20% greater than that of the no-rhizobia soil. Addition of rhizobia also increased exchangeable Cd and specifically-adsorbed Cd by 25 and 93%, respectively, in Red soil. No considerable differences were found for the total immobilization of Zn and Cd as well as their distribution in various solid fractions of Cinnamon soil in the absence and presence of rhizobial cells. In terms of soil components, it is assumed that bacterial biomass had a relatively less impact on the species of heavy metals bound with Fe oxides. Results suggested that the retention and speciation of heavy metals in soil are governed largely by the interactions of bacteria with various inorganic and organic soil constituents. The data are useful in understanding the impact of microorganisms on the behavior, mobility and transformation of heavy metals in soil environments.     

Distribution and fractionation of heavy metals in pairs of arable and afforested soils in Denmark

Afforestation of sandy arable soils in northern Europe is likely to lead to an increase in the soil's acidity and changes in the behaviour of the organic matter, and this might affect the ability of the soil to retain heavy metals. It is important to assess the impact of such a change in the land use on the solubility of the heavy metals and to assess the risk of leaching to surface‐ and groundwater and the possible entrapment of heavy metals in the tree canopy. The impact of afforestation was assessed by excavating soil profiles in adjacent 34‐year‐old Norway spruce stands and arable plots at four different sites. We found that after 34 years the pH had decreased and cations were depleted in the topsoil under forest. The aqua regia‐extractable heavy metals were determined, and the heavy metal binding within the soil was assessed using a modified version of the BCR (Community Bureau of Reference) sequential extraction procedure. Higher contents of heavy metal were found in the arable plots in the loamy sand soils. Cadmium was found only in the most mobile fractions. The content of Pb in the subsoil was strongly correlated with the clay content, but not in the topsoil, which suggested that Pb had been added to the topsoil. We found strong correlations between the clay content and the Cu, Ni and Zn in the residual fraction, leading us to conclude that much of the Cu, Ni and Zn is of geological origin. No significant differences in the heavy metal fractionation between forest and arable soil were found, presumably because 34 years of different land use is not long enough to produce such differences.     

Mycological complexes in Holocene and Late Pleistocene paleohorizons and in fragments of paleosols

Fragments of buried Late Pleistocene (30000-year-old) and Early Holocene (10000-year-old) paleosols contained viable complexes of microscopic fungi. The mycobiota of these paleosols represents a pool of fungal spores that is lower in number and species diversity as compared to that in the recent humus horizons and higher than that in the inclosing layers. The central part of the paleosol profiles is greatly enriched in microscopic fungi. In the intact humus horizons of the Late Holocene (1000–1200 years) paleosols, actively functioning fungal complexes are present. These horizons are characterized by their higher level of CO₂ emission. The buried horizons, as compared to the recent mineral ones, contain a greater fungal biomass (by several times) and have a higher species diversity of microscopic fungi (including fungi that are not isolated from the recent horizons). Nonsporulating forms are also present there as sterile mycelium. The seasonal dynamics of the species composition and biomass of the fungal complexes were more prominent and differed from those inherent to the surface soil horizons. In the buried humus horizons, the dynamics of the fungal biomass were mainly due to the changes in the content of spores. The data on the composition of the fungal complexes in the buried soils confirm (due to the presence of stenotopic species) the results of paleobotanic analyses of the past phytocenoses or do not contradict them.