土壤环境质量研究的回顾和展望

土壤环境质量作为土壤质量的重要组成部分之一，是表征土壤容纳、吸收和降解各种环境污染物的能力。目前对土壤环境质量定义尚无统一的意见，陈怀满教授给出了土壤环境质量的参考定义，指出土壤环境质量是在一定的时间和空间范围内，土壤自身性状对其持续利用和其他环境要素，特别是对人类或其他生物的生存、繁衍以及社会经济发展的适宜性。本文从土壤污染、环境容量、污染物迁移转化、生态安全以及修复技术等角度回顾了国内外土壤环境质量的研究内容。对今后土壤环境质量的发展趋势进行了展望，指出土壤环境质量在我国的研究和应用还比较薄弱，在土壤持续污染物防治、土壤污染风险评价等方面急需加强。随着我国环境形势日益严峻，土壤环境污染机理及其防治也提上议事日程，土壤环境质量的研究和应用对于我国的农业安全、食品安全、生态安全都具有极为重要的理论和现实意义。     

梯级开发河流污染物的积累性和缓冲性——兼论惰性物的积累模型

本文论述了梯级开发河流的“水库－河流”两重性，当该河流呈水库性质时，会发生对污染物的积累和缓冲；同时，论述了惰性物质氯离子（Ｃｌ＾－）的积累模型，提出了破坏此积累性和缓冲性的临界流量，以及如何用它来改善梯级开发河流的水质。     

土壤综合治理技术─—空气抽取法和堆肥法结合使用治理土壤污染

文中介绍了国外用土壤空气抽取法和堆肥法清除土壤中有机溶剂、芳香烃类和石油污染物的技术及其应用。这两种方法单独使用均可成功地治理有害废弃物。实践证明，将这两种技术串联使用可更有效地处理土壤中污染物及加速生物降解过程。根据现场特点，利用多种治理技术综合治理土壤污染物是治理污染物的发展方向。     

土壤综合治理技术─—空气抽取法和堆肥法结合使用治理土壤污染

文中介绍了国外用土壤空气抽取法和堆肥法清除土壤中有机溶剂、芳香烃类和石油污染物的技术及其应用。这两种方法单独使用均可成功地治理有害废弃物。实践证明，将这两种技术串联使用可更有效地处理土壤中污染物及加速生物降解过程。根据现场特点，利用多种治理技术综合治理土壤污染物是治理污染物的发展方向。     

土壤对钻井废水中有机污染物吸附作用研究

分析了钻井废水中有机污染物在土壤中吸附的机理,对吸附量和有机负荷的关系进行了阐述;针对钻井废水有机污染物在土壤中的吸附和解吸过程进行了实验研究。实验表明:钻井废水中有机污染物在土壤中的吸附量与土壤有机负荷的关系符合初始质量等温线;土壤中天然有机质含量越高,对钻井废水中有机污染物吸附能力越强;土壤对钻井废水中有机污染物具有一定的持久吸附作用;天然有机质含量越高的土壤对钻井废水中有机污染物的持久吸附能力越强。     

土壤污染的健康危害与修复技术

土壤污染是当今社会面临的重要环境问题之一,已经对人体健康构成了严重威胁。本文将土壤污染物分为有机污染物、无机污染物、生物污染物和放射性污染物,并阐述了各类污染物对人体健康的危害,介绍了具有广阔应用前景的污染土壤修复技术,即植物修复技术和微生物修复技术。最后,本文还对解决土壤污染问题提出了具体的建议。     

NAPL态石油类污染物在黄土中迁移的稳态数学模型

根据NAPL态石油类污染物迁移的特点，建立了NAPL态石油类污染物在土壤中迁移的稳态数学模型，提出了综合污染系数的概念；根据延安黄土高原地区土壤和石油类污染物的特性测定了NAPL态石油类污染物对黄土的综合污染系数S＝6－8。最后在实验室条件下对模型进行了验证，结果表明模型计算值与实验值能够较好吻合。     

石油类污染物在土壤中的环境行为

土壤中石油类污染物的环境行为一直是环保界研究的重点。为此,简述了土壤中石油类污染物的来源、危害及存在状态,介绍了其在土壤中的迁移、吸附和降解行为,以及其行为特征和影响因素。全面了解土壤中石油类污染物的环境行为,对保护生态环境、推动石油工业的持续发展具有重要意义。     

土壤净化功能的原理及其利用

本文通过对土地处理系统的剖析，从土壤去除有机物，悬浮物，氮，磷，汞量重金属，病原散生物，污染空气。以及对酸性沉降物的缓冲等诸方面，讨论了土壤净化功能的原理，概括了土壤净化过程，既包括物理的，化学的和生物的作用，又包括物理化学，生物化学的作用，为更好地研究，利用和管理土地处理系统，充分发挥土壤的净化功能提供研究的方向。     

崂山风景区土壤重金属元素环境容量的计算

崂山在青岛土壤重金属的综合污染指数排序中位于第2位，重金属污染问题比较突出。通过计算崂山风景区土壤重金属元素的静态容量和动态容量，对二者进行了比较。重金属元素环境容量的计算，可以为了解土壤承载力，实现污染物容量总量控制等提供科学依据。     

FACTORS AFFECTING SPRING RUNOFF ON TWO FORESTED WATERSHEDS1

ABSTRACT Spring runoff from two forested watersheds in northern Minnesota is a function of annual snowfall, soil water recharge, and water supply rates. A drainage basin with a clay soil and a hardwood overstory had greater snowmelt and water supply rates than another drainage basin with a sandy soil and conifer overstory. The average soil water recharge rate for the clay soil was 28 percent less than for the sandy soil. The lower recharge rate of the clay soil resulted in spring runoff which averaged 40 percent of water supplied during the three year study while an average of two percent was produced on the sandy soil. Soil frost which affected soil water recharge varied between soil types and was influenced by amount of soil water storage and snow cover.     

Diversity of hydric soils in North Carolina,USA

Hydric soils are used as supportive evidence for wetland delineations by federal and state agencies and by the private sector in North Carolina, USA. An analysis of hydric soil distribution and hydric soil characteristics was conducted with county soil surveys and soil taxonomy of the USA. Approximately 100 hydric soils have been used for soil mapping in North Carolina, and they represent seven of the ten soil orders in soil taxonomy. An estimated 23% (2.9 million ha) of the land surface area in North Carolina supports hydric soils. Approximately 96% of the known hydric soil acreage was found in the coastal plain of North Carolina. Over one-third of the soils were hydric Ultisols, which represented close to 10% of the land surface area. The other soil orders with extensive hydric soil acreage included Histosols, Inceptisols, and Entisols. The soil orders were separated into great groups of soil taxonomy to discuss soil profile characteristics. Landscape positions and associated wetland communities were also presented. In North Carolina, a statewide inventory of wetlands does not exist and soil surveys offer a resource for a first approximation of wetland boundaries.     

Soil compaction--indicators for the assessment of harmful changes to the soil in the context of the German Federal Soil Protection Act

Soil compaction in agriculture induced by large-scale equipment is of growing concern. Heavy wheel loads used in arable cropping have the potential to cause irreversible damage to the subsoil structure and may lead to harmful soil compaction. In order to sustain or improve soil health or fitness on a sustainable basis, indicators are needed to assess the changes in the soil structure and the respective soil functions. This requires an adequate verification of methods for distinguishing between the impairment of soil structure and the disruption of soil functions, and for the respective subject of protection. In this article the link between existing models of soil physical prognosis, practical guidelines, and criteria for the identification of affected soil structure is demonstrated, and a viable concept to distinguish harmful changes to the soil is presented. The concept consists of methods for soil physical analysis such as "pre-compression stress" and "loading ratio", practical recommendations for best management practice, and an indicator-based model for the identification of harmful subsoil compaction derived from a research project for the German Federal Environmental Agency, making it possible to determine for a respective location the required level of action far beyond the common practice of precautions against harmful soil compaction.     

土壤环境监测技术规范中的土壤环境质量评价问题

近年来,场地和土壤污染勘查评价与修复逐渐发展成为环境科学和土木工程领域的热点,场地和土壤修复业务随之愈来愈多。但土壤修复理论和技术发展相对缓慢,无法满足土壤修复行业发展的需要。实践中,在场地和土壤污染勘查与评价的现行标准中,对土壤环境质量评价仅考虑了土壤中某物质成分的人为超标问题,而忽视了土壤中自然异常而导致土壤中某物质成分超标问题的评价,且误将土壤中某物质成分的超标等级定为土壤污染程度等级的全部。针对这些问题,本文通过研究,在深入分析各领域土壤污染评价差异的基础上,提出了土壤污染评价的一般过程、方法和标准,供标准修订参考。     

Adsorption-desorption behavior of copper at contaminated levels in red soils from China

Adsorption-desorption of copper (Cu2+) at contaminated levels in two red soils was investigated. The red soil derived from the Quaternary red earths (clayey, kaolinitic thermic plinthite Aquult) (REQ) adsorbed more Cu2+ than the red soil developed on the Arenaceous rock (clayey, mixed siliceous thermic typic Dystrochrept) (RAR). The maximum adsorption values (M(A)) that are obtained from the simple Langmuir model were 25.90 and 20.17 mmol Cu2+ kg(-1) soil, respectively, for REQ and RAR. Adsorption of Cu2+ decreased soil pH, by 0.8 unit for the REQ soil and 0.6 unit for the RAR soil at the highest loadings. The number of protons released per Cu2+ adsorbed increased sigmoidally with increasing initial Cu2+ concentration for the RAR soil, but the relationship was almost linear for the REQ soil. The RAR soil released about 2.57 moles of proton per mole of Cu2+ adsorbed at the highest Cu2+ loading and the corresponding value for the REQ soil was 1.12. The distribution coefficient (Kd) decreased exponentially with increasing Cu2+ loading. Most of the adsorbed Cu2+ in the soils was readily desorbed in the NH4Ac. After five successive extractions with 1 mol L(-1) NH4Ac (p 5.0), 61 to 95% of the total adsorbed Cu2+ in the RAR soil was desorbed and the corresponding value for the REQ soil was 85 to 92%, indicating that the RAR soil had a greater affinity for Cu2+ than the REQ soil at low levels of adsorbed Cu2+.     

Enhancing the Ability of a Soil Moisture‐based Index for Agricultural Drought Monitoring by Incorporating Root Distribution

Agricultural drought differs from meteorological, hydrological, and socioeconomic drought, being closely related to soil water availability in the root zone, specifically for crop and crop growth stage. In previous studies, several soil moisture indices (e.g., the soil moisture index, soil water deficit index) based on soil water availability have been developed for agricultural drought monitoring. However, when developing these indices, it was generally assumed that soil water availability to crops was equal throughout the root zone, and the effects of root distribution and crop growth stage on soil water uptake were ignored. This article aims to incorporate root distribution into a soil moisture‐based index and to evaluate the performance of the improved soil moisture index for agricultural drought monitoring. The Huang‐Huai‐Hai Plain of China was used as the study area. Overall, soil moisture indices were significantly correlated with the crop moisture index (CMI), and the improved root‐weighted soil moisture index (RSMI) was more closely related to the CMI than averaged soil moisture indices. The RSMI correctly identified most of the observed drought events and performed well in the detection of drought levels. Furthermore, the RSMI had a better performance than averaged soil moisture indices when compared to crop yield. In conclusion, soil moisture indices could improve agricultural drought monitoring by incorporating root distribution.     

Strategies for determining soil-loss tolerance

Excessive soil losses due to erosion or lateral displacement by machinery impair productivity. Some soil loss is tolerable, but not so much that plant productivity diminishes. Thus productivity is the dominant concern in determining soil-loss tolerance. The effects of soil loss on productivity, however, are difficult to determine. Therefore, two alternatives are discussed for determining the limits of soil loss, or soil-loss tolerance. These alternatives are the maintenance of soil organic matter and, for shallow and moderately deep soils, the maintenance of soil depth. They are not new strategies, but our rapidly increasing knowledge of the dynamics of soil organic matter and the rates of soil formation from bedrock or consolidated sediments warrants the reconsideration of these alternatives. Reductions in either soil organic matter or the depth of shallow or moderately deep soils will lead to declining productivity. Soil organic matter, considered to be a surrogate for productivity, is much easier to monitor than is productivity. Also, there are many computer models for predicting the effects of management on soil organic matter. Recently compiled data on rates of soil formation suggest that soil losses of 1 t/a (2.24 Mg/ha yr) are greater than the rate of replenishment by the weathering of lithic or paralithic material in all but very wet climates.     

中国土壤修复与治理的投融资政策最新进展与展望

中国目前的土壤污染修复资金主要来源于政府财政性投资,融资渠道较为单一。《土壤污染防治行动计划》实施后,如何满足实现土壤污染修复与治理目标的投资需求是一个迫切需要解决的问题,充分创新发挥市场力量,建立长效的融资政策机制是核心内容。本文评估了中国土壤污染修复与治理投融资政策现状,识别了投融资面临的关键问题和挑战,提出了"十三五"时期中国土壤修复与治理的投融资机制建设的政策建议,为"十三五"时期中国土壤修复投融资模式创新提供管理技术支撑。     

沙枣对滨海盐渍土的改良作用探究

实验以野生沙枣为研究对象，在根系附近采集实验组土样，在周围裸露土地上采集对照组土样。通过实验组与对照组的各项指标对照表明，在盐渍土上种植沙枣，不但可增加土壤中的含水量，而且可增加土壤中的空气体积和有机质含量，提高土壤中的K含量，降低土壤中pH值。沙枣对滨海盐渍土有着很好的改良效果和一定的经济效益。