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1.
中国土壤化学的研究与展望   总被引:7,自引:1,他引:6       下载免费PDF全文
回顾土壤化学中重要研究领域的研究进展,可为21世纪土壤科学的长远发展提供基础学科分支的理论依据。本文在简短回顾我国土壤化学发展历程的基础上,总结讨论了近年来我国土壤化学的研究特点、现状及部分进展,并据此对该领域的未来研究趋势及重点发展方向作了概括性展望。综合分析认为,对土壤进行宏观调控要以土壤微观性质的认识为前提。新近基于分子尺度微观光谱技术对土壤微观性质的原位观测及认识的飞跃是近年来我国土壤化学研究领域迅速发展的基础;近代土壤学、环境科学、生态学、生物地球化学、化学、生物学以及地质医学等多学科的交叉与渗透又进一步拓展了传统土壤化学研究的领域,促进了土壤化学多个分支学科的形成和发展;立足农业生产,同时着眼于人类生存环境转变,建立具有中国特色的可变电荷土壤化学理论与技术体系,完善现代土壤学理论,是今后中国土壤化学研究的重要发展方向。  相似文献   

2.
土壤电化学的建立与发展   总被引:6,自引:1,他引:5  
于天仁 《土壤》1999,31(5):231-235,254
虽然在土壤学中“电化学”这个名称由来已久,但文献中对土壤电化学的含义的认识却很不相同。60年代初,我们分析了土壤化学的发展史和现状,也参考了电化学和胶体化学的发展情况,提出了土壤电化学的范畴是研究土壤中带电粒子间的相互作用及其化学表现,近40年来的研究成果表明,关于土壤电化学的这个定义及其范畴是适当的。根据土壤化学的发展趋势和我国土壤分布的特点,我们从水稻土的物理化学、可变电荷土壤的电化学和土壤电分析化学等方面的研究,发展土壤电化学。经过几十年的努力,我国已基本建立起较完整的土壤电化学体系,有关的研究成果对促进我国土壤科学的发展及提高我国土壤学的国际地位作出了积极的贡献,但是,我国的土壤电化学仅仅走过了开创阶段,真正的理论上的突破则有待于今后的努力。除了学科本身的发展以外,土壤电化学的实际应用也应是逐渐开拓的一个重要方面。有理由相信,土壤电化学基本理论在国民经济包括农业生产和生态环境保护中将得到日益广泛的应用。  相似文献   

3.
现代分析技术在土壤腐殖质研究中的应用   总被引:12,自引:0,他引:12       下载免费PDF全文
梁重山  刘丛强  党志 《土壤》2001,33(3):154-158
土壤腐殖质的研究已成为土壤学、环境化学和地球化学等领域的热点方向之一。应用核磁共振光谱 (NMR)、红外光谱 (IR)、荧光光谱 (FS)、电子自旋共振谱 (ESR)等现代分析技术 ,对在土壤腐殖质组成和结构研究中取得的主要成果进行了综述。  相似文献   

4.
环境土壤学是一门新兴的、土壤学和环境科学交叉融合的综合性学科,其研究重点从早期服务于农业安全生产发展至现在的土壤环境与健康,本文从土壤外源物质侵袭和土壤质量演变对土壤环境影响等方面回顾了环境土壤学发展历程。土壤污染物对土壤环境质量影响是以土壤元素背景值和环境现状调查为基础,以明确污染物形态,揭示土壤反应过程机制,评估污染效应,开展土壤环境修复工程为主线不断发展更新。土壤质量演变研究中碳、氮、硫、磷元素循环从土壤肥力和农业非点源污染的探讨拓展至土壤对全球气候变化的适应与响应;土壤退化研究则从对土壤生产力或功能丧失的研究发展至全球气候变化背景下农业发展可持续性及土壤生态功能的研究。环境土壤学在今后有四个重要发展趋势:提倡多学科交叉融合;评估全球气候变化对土壤元素循环的潜在影响;完善土壤健康评价框架中的土壤环境评价指标建立;学科发展服务于国家重大需求。  相似文献   

5.
张宏 《土壤》1991,23(5):227-230,245
文章从土壤学-土壤圈学乃至圈态学的角度,阐述了土壤电化学的特点和未来发展趋势。并提出了具体的研究课题。  相似文献   

6.
马菲  周健民  杜昌文 《土壤学报》2022,59(3):642-653
土壤分析是土壤学研究及应用的前提和基础,传统化学土壤分析方法逐渐不能适应现代土壤学海量信息数据快速获取的需求。激光诱导击穿光谱作为一种全新的、反映土壤组成元素原子信息的光谱技术,其无需对样品进行复杂前处理,可实现原位、快速、多元素连续在线检测,每条光谱记录土壤样本独一无二的特征,可以视为土壤“指纹”,成为现代土壤分析的有效技术之一。首先介绍和分析了激光诱导击穿原子光谱的原理、光谱获取的主要影响因素、光谱数据处理的化学计量学方法等;然后阐述和梳理了基于激光诱导击穿光谱技术在土壤分析方面的应用成果和进展,包括土壤鉴定、土壤养分评估、土壤重金属测定、微观/介观尺度土壤原位表征等;最后讨论和总结了激光诱导击穿光谱技术在土壤分析中所面临的挑战及其应用展望。  相似文献   

7.
土壤地理学是研究土壤时空分布规律、形成过程及其资源环境效应的土壤学学科分支,其主要目标和任务是理解土壤形成演化的关键过程与影响因素并预测未来土壤-环境的共同演化特征,揭示土壤资源分布规律、利用前景和保护对策,为农业、生态环境保护等提供科学依据,支撑土壤普查、耕地保护等国家目标。21世纪特别是新时代10年以来土壤地理学取得了一些重要的进展,研究对象和内容也发生了很大的变化,逐渐向以土壤为核心的地球表层系统科学发展,高强度人为活动和全球气候变化背景下的土壤时空演变研究愈加活跃。土壤地理学主要发展趋势包括土壤信息获取方式正在发生变革,数字土壤制图向融合过程机理与数据驱动发展,土壤时空信息的应用范围更加广泛。未来土壤地理学优先发展领域包括:以关键带研究带动土壤发生和演变研究的革新,基于多传感器的土壤综合观测原理与技术,多尺度数字土壤制图与时空变化预测等。  相似文献   

8.
骆永明 《土壤学报》2008,45(5):846-851
结合国内外研究现状和发展趋势分析,提出开展土壤环境的生物地球化学过程、质量演变和风险管理研究。认为将土壤环境划分为内部、界面和外部三部分,有助于认识土壤环境中污染物的交换与循环规律及其相互影响。强调了开展土壤环境的物理-化学-生物学-地学交叉、综合研究的必要性,并从土壤颗粒表面-溶液、土壤-生物、土壤-植物、土壤-大气、土壤-水体等土壤环境子系统探讨了科学问题,展望了未来研究方向,旨在促进不同尺度土壤环境的质量变化规律与修复调控研究。  相似文献   

9.
固碳土壤学的核心科学问题与研究进展   总被引:67,自引:10,他引:57  
土壤碳固定是当前有关陆地生态系统碳循环与全球变化的地球表层过程研究的重要优先领域。国际社会对全球农业温室气体减排的需求,驱动着土壤学对土壤固碳容量与潜力、固碳与减排的过程与机理的前沿探索,并越来越呈现为一个独特的土壤学新兴分支学科——固碳土壤学(SoilScience of C Sequestration)。本文围绕固碳土壤学的基本科学问题,回顾了最近10多年来,特别是最近5年来国内外关于土壤固碳研究的主要进展,讨论了固碳土壤学中的核心科学问题是土壤固碳容量与固碳作用的机理,论述了土壤物理保护、碳化学结合与碳化学转化稳定与固碳容量及稳定化的关系,提出了土壤-植物(作物)-微生物相互作用是当前固碳土壤学的前沿领域和深化方向,并结合国内对水稻土固碳的研究进展,提出了固碳土壤学的概念性框架,认为我国亟待加强固碳土壤学研究,深入探索我国农业经营管理特色下土壤固碳容量、过程、机理,丰富和发展农业土壤碳循环理论,并服务于全球变化生物学和国家碳管理。  相似文献   

10.
提升对土壤认识, 创新现代土壤学   总被引:7,自引:1,他引:6       下载免费PDF全文
赵其国 《土壤学报》2008,45(5):771-777
土壤是农业生产的基础,是人类赖以生存的基石,也是人类食物与生态环境安全的保障。随着现代科技和国家社会经济的快速发展,土壤的地位与功能正在发生变化。本文基于土壤与土壤学科及国民经济发展需求的关系为出发点,指出了当前对我国土壤的重要性认识正在从农业生产向环境安全、资源利用、生态健康及全球变化等方向转变与提升。同时,明确了现代土壤学的内涵和创新现代土壤学的战略思想,全面、系统、前瞻性地提出了现代土壤学的研究前沿与特点,以及现代土壤学研究领域所面临的挑战与展望,为我国现代土壤学的发展指明了方向。  相似文献   

11.
Donald L. Sparks 《Geoderma》2001,100(3-4):303-319
Contributions in the field of soil chemistry have immensely benefited humankind, including enhanced agricultural production and the quality of our environment. This review focuses on research breakthroughs since the mid-1970s and delineates frontiers in soil chemistry for the upcoming decade. However, early contributions in ion exchange, sorption phenomena, and soil acidity are highlighted. Beginning in the 1970s, soil chemistry paradigms shifted from the chemistry of plant nutrient reactions/processes in soils to studies on environmental soil chemistry. The latter included research on: acid rain effects on soils and waters; trace metal/metalloid, environmentally important plant nutrient, radionuclide, and organic chemical reaction mechanisms and retention; speciation of soil contaminants using chemical extraction and molecular scale analytical techniques; facilitated colloid transport of metals and organic chemicals; humic substance structure; kinetics of soil chemical processes; redox transformations of contaminants in soils; modeling of soil chemical reactions; and soil remediation. Frontiers in soil chemistry over the next decade will undoubtedly involve the use of advanced in situ technologies in combination with interdisciplinary research efforts to unlock important information on: speciation of contaminants in soils; cycling of trace elements and nutrients and impacts on global climate change; development of models to accurately predict the rate, fate, and transport of contaminants in the subsurface environment; elucidation of mechanisms for microbial transformations of contaminants; unraveling the precise structure of soil organic matter; and enhanced understanding of rhizosphere chemistry. In summary, the future of soil chemistry is bright for the 21st century.  相似文献   

12.
The foliar status and the factors affecting the foliar chemistry in a natural Aleppo pine forest grown on calcareous soils in Greece were examined. It was found that the Aleppo pine needles had significantly higher calcium (Ca) concentrations, but significantly lower concentrations of magnesium (Mg), potassium (K), phosphorus (P), iron (Fe) and manganese (Mn) than the respective average concentrations of natural Aleppo pine forests in Spain. It was also found that only foliar Ca and Mn had a significant correlation with the exchangeable Ca and available Mn in soils, respectively. Principal component analysis showed that the nature of the calcareous parent material, (colluvial rocks and hard limestones) were the main factors affecting both foliar and soil chemistry. This finding is important as colluvial soils always coexist with other soil types in hilly and mountainous regions containing calcareous material.  相似文献   

13.
Oxygen-18-labeled phosphate (OLP) and natural abundance 18O have been used as tools for elucidating the dynamics of phosphorus (P) in soils, yet much remains poorly understood. The objective of this research was to determine the extent of preferential soil sorption across the range of species contained within OLP. A variety of soils were shaken with water containing 65.5 mg L?1 OLP-P for a 24-h period. Following shaking, the OLP species remaining in the solution were determined. Increasing the oxygen-18 atoms in the phosphate molecule by one resulted in a 1.8% increase in the amount of that OLP species sorbed to the soil, and this increase in sorption was uniform across soils. A strong correlation (r2 = 0.94) was found between the amount of phosphate sorbed and the Mehlich 3 P saturation ratio of the soil. These results will be useful for studies using natural abundance and enriched 18O-phosphate in soils.  相似文献   

14.
A comprehensive study began in 1980, at the Loch Dee catchment (south west Scotland), to study the effects of acidification and coniferous afforestation on streamwater ecology. When the project started, acid emissions were high but have since declined and stabilised. Average rainfall pH did not change significantly during the study period but total sulphate concentrations declined by 30%. The Loch Dee basin has three main subcatchments. Almost 70% of the Green Burn subcatchment was planted with Sitka spruce, between 1973 and 1975 and canopy closure has occurred at lower altitudes. Comparison of the water chemistry of the Green Burn and the Dargall Lane was done with cusum plots. The pH in the Green Burn has fallen relative to the Dargall Lane, whereas total and non-marine sulphate concentrations have remained unchanged over the last 10 years.  相似文献   

15.
Nests of the yellow meadow ant (Lasius flavus) occur at high densities in grasslands worldwide. Although many studies have shown that L. flavus nests influence soil nutrient contents, little is known about their effect on soil nutrient cycling rates. The aim of this study was to examine the role of nest-mounds inhabited by L. flavus as potential ‘hot spots’ for soil nutrient cycling. Six pairs of nest-mounds and control soils were selected at a grassland site at the plateau of the Alter Gleisberg (Thuringia, Central Germany). L. flavus significantly modified the soil environment within the nest. In comparison to the control soils, nest-mounds were characterized by slightly higher soil temperatures during the summer months. In addition, we found that nests were related to decreased potential C mineralization rates and increased potential net N mineralization rates. Nest-mound soil exhibited lower amounts of SOC, hot-water extractable DOC and DN, and higher concentrations of leachable DOC and DN. Moreover, ants promoted the enrichment of base cations in the nest. Differences in the soil environment between nests and control soils were possibly a result of the burrowing activity of ants, soil mixing, accumulation of aphid honeydew, and decreased plant-derived nutrient inputs into the nest-mound soil. In conclusion, L. flavus nest-mounds had a significant but element dependent effect on the soil nutrient cycling and may represent cold spots for C cycling and hot spots for N cycling. Thus, L. flavus nests increase the spatial heterogeneity of soil properties and create unique micro-sites within grassland ecosystems.  相似文献   

16.
Serpentine soils represent a stressful growing environment for most plants due to a number of edaphic factors, including low concentrations of plant nutrients and high concentrations of heavy metals. Plants in these environments range from weakly resistant to strictly endemic, yet it remains unclear whether serpentine habitat affinity affects plant chemistry, including elemental distribution among various organs. We address this knowledge gap using three confamilial pairs of endemic and non‐endemic plants. First, we determined total and phytoavailable soil concentrations of four nutrients (Ca, Mg, P, K) and three heavy metals (Co, Cr, Ni) across 11 serpentine study sites. Next, we determined the concentrations of these elements in leaves, flowers, and seeds in plants of each species growing on serpentine soil. Soils at the study sites were characteristically high in concentrations of Mg, Ni, Co and Cr, and low in K, P and Ca relative to non‐serpentine soils. Habitat affinity was critical in determining the organ concentrations of Ca, Mg, K, and Co, although concentration often varied by organ type. Relative to non‐endemics, endemics had higher concentrations of Mg and K across all organ types, whereas Ca concentrations were higher for non‐endemics in the leaves but equal for the two reproductive organs. While no difference was observed in Ni or Cr concentrations, endemics contained 56% less Co than non‐endemics across all organ types. These results suggest that serpentine endemics are more effective at acquiring potentially limiting nutrients compared to non‐endemic species, but both endemic and non‐endemic plants exclude most phytotoxic heavy metals. Therefore, growth on serpentine requires common physiological responses of all plants, though high variation in uptake of some key nutrients and exclusion of some metals may reflect differential adaptation to serpentines by non‐endemic and endemic plants.  相似文献   

17.
以酶化学教学为例,论述了如何运用以旧导新法,实验推理法和形象思维法解决生物化学教学中的重点、难点问题,以提高教学效果。  相似文献   

18.
Morphological, chemical and mineralogical studies were made on different types of nodules and concretions occurring in Gleysols, Ferralsols and Vertisols of the R. Chinit area, Kompong Thorn Province, Cambodia.

The examinations indicated that nodules have developed through impregnation of soil matrix with iron and/or manganese oxides, whilceoncretions have formed through periodical precipitation of iron oxide around ferruginous or manganiferous nuclei to the exclusion of surrounding soil materials. Alternation of wet and dry seasons is believed to play an important part in the localization of iron and manganese into mottles and their subsequent hardening. The proportion of anhydrous iron oxides (hematite, maghemite) to hydrated iron oxide (goethite) appears to be closely related to the degree of desiccation of soils in dry seasons. Decomposition of kaolinite in the nodules and concretions was suggested by their lower kaolinite, and higher amorphous silica and alumina contents as compared to the surrounding soils. Mechanisms involved in the genesis of each of the types are further discussed.  相似文献   

19.
公开出版的专业书籍中土壤可溶性盐及其组分计算公式存在诸多意料不到的错误,却没有引起大家的重视并提出修正措施,这些错误的存在可能会导致盐分含量计算结果的出错和对盐碱土分类分级的错误判定。本文选取出版日期介于2000—2020年包含土壤可溶性盐总量和阴阳离子(CO32-、HCO3-、SO42-、Cl-、K+、Na+、Ca2+、Mg2+)含量9个指标计算公式的12本专业书籍为研究对象,基于相关概念、理论基础、实验原理和实验方法进行公式推导。结果发现,9个指标共出错68次,其中HCO3-出错次数最高,为11处,占比16.2%;其次为Ca2+,10处,占比14.7%;最低的是可溶性盐总量和Cl-,4处,占比5.88%。根据9个指标的出错特征,将其归纳为系数2、换算系数、公式、指代意义和公式不规范5种出错种类。5种出错种类中,换算系数出错次数最高,31处,占比45.6%;其次为公式,13处,占比19.1%;最低的是系数2,4处,占比5.88%。通过对土壤可溶性盐及其组分计算公式出错种类的特点和原因解析,指出问题所在,并提出了纠正措施,以期为相关公式的修正提供借鉴。  相似文献   

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