施肥措施对重金属污染土壤-植物系统影响的研究进展

植物修复作为一种原位修复方法，因其投入成本低、拥有良好的经济效益和生态协调性等优点而成为国内外研究热点，在重金属污染农田实地得到广泛应用。本文综述施肥农艺措施强化重金属污染土壤植物修复以及对土壤-植物系统影响的研究进展，如土壤重金属含量和生物有效性的影响等，以便进一步提高植物修复效率，为今后规模化修复重金属污染农田土壤提供参考。     

苎麻修复重金属污染土壤研究现状

植物修复技术适用于中、低浓度污染土壤的治理,具有良好的生态效益。苎麻对重金属具有较强的耐受和吸收能力,是一种修复重金属污染土壤潜力较大的目标植物。综述了苎麻作为修复作物的特点,对镉、铅以及其它重金属的抗性,对重金属污染土壤的修复效果,并对苎麻修复重金属污染土壤研究前景进行了讨论。     

土壤修复剂（金无踪）的推广与应用

我国耕地重金属污染日益加剧，已严重威胁到食品安全和人体健康，亟需治理和修复。金葵子公司经过多年的探索和研究，成功研制出用于治理重金属污染的土壤修复剂——金无踪。试验示范和实际应用表明，施用金无踪土壤修复剂可有效降低土壤中重金属离子的生物有效性，减少作物对重金属的摄取量，保证农产品的安全并提高农产品的质量和产量。     

辽宁烟区土壤保育与修复技术研究

土壤是影响烟叶质量的首要环境因素。植烟土壤的保育与修复技术是解决烟叶质量发展瓶颈问题的关键。以辽西朝阳为例,通过对种植制度、精准施肥技术、土壤改良技术和土壤修复技术进行分析,找出原因,修复植烟土壤物理结构、平衡土壤养分、改善土壤生态环境、减少病虫危害,保持现有健康土壤不再退化,实现退化土壤逐渐修复,维护烟区烟叶生态安全的红线,达到烟叶质量提升和种烟效益增加的目标任务。     

亚麻修复重金属污染土壤的研究与应用

亚麻是一种重金属污染土壤修复的理想作物之一,不仅对重金属具有较强的耐受性,而且对重金属有很强的吸附作用,适当进行调节剂、水分、肥料、微生物、p H等外界条件使用或调节可以提高亚麻对重金属的吸收、转移及积累能力。为提高亚麻对重金属污染土壤的修复能力,要加强亚麻品种培育及种质资源筛选,积极开展亚麻重金属污染土壤修复技术研究,对亚麻进行规模化、机械化种植,促进重金属污染土壤的治理。     

双季稻丰产栽培的清洁生产技术

根据多年的研究结果,提出了一套包括品种替代、化肥污染控制、农药污染控制、水稻健身栽培、土壤质量提升、灌溉与水体净化等技术的双季稻丰产栽培中的清洁生产技术体系,对中国南方双季稻区的水稻清洁生产具有重要的指导作用。     

收益型植物修复镉污染耕地土壤的研究进展

植物修复是当前修复镉(Cd)污染耕地土壤的重要方法之一,而如何平衡土壤修复效果和经济效益是应用推广植物修复技术的关键。文章在提出收益型植物修复概念的基础上,按用途将收益型植物分为3类:非食用型、可安全食用型和可选择进入食物链型,分类综述不同类型收益型植物对Cd污染耕地土壤的修复效果,以及修复过程中产生的修复成本、经济效益,以期为Cd污染耕地土壤植物修复推广和种植结构调整选取合适的替代作物提供参考。     

向日葵、油菜对镉胁迫反应及对镉污染土地修复作用研究进展

随着人类活动的增加,越来越多的重金属进入土壤中造成土壤污染,其中镉是对人体毒害最强的,土壤镉污染治理已经成了人们最关心的问题之一。对比不同的土壤重金属污染治理的方法,植物修复被认为是最好的。总结了向日葵和油菜对镉胁迫的反应,以及它们对镉污染土地的修复作用,并对以后的研究方向进行了探讨。     

喀斯特地区茶园土壤酸化机理及防治措施

近年来，随着中国农业的迅速增长，茶叶的生长受到越来越多的关注。然而，随着时间的推移，土壤pH值的变化也变得越来越严峻。本研究通过综合研究贵州等地的茶叶生长情况，探讨了影响土壤pH值的内部原因与外部影响。采取有效的技术手段，如使用白云石粉、合理的施肥以及进行有效的生态修复，可以有效地阻止茶园的土壤变质。为茶园土壤调控管理和茶园发展规划提供科学依据。     

茶园稀土污染修复的技术途径

本文针对茶园土壤稀土污染问题,提出污染修复的技术途径如物理修复、化学修复、植物修复和微生物修复等,并对这些修复技术作出比较.     

Predicting soil moisture condition in arbitrary agricultural lands using the digital soil map and soil physical properties database

To predict soil moisture condition in arbitral agricultural lands by taking spatial distribution of soil type in a watershed into account, we investigated the possible proper methods of determining the soil hydrological parameters using available soil physical properties database of Japanese soils, “SolphyJ”, and the digital soil map. In this study, simulation of soil moisture was conducted at three neighboring locations, including monitoring sites each in Toyama and Fukui cities. The simulated results of soil moisture appeared to be improved when hydraulic parameters were obtained by fitting water retention data of SolphyJ compared to the parameters estimated by neural network with soil texture and dry bulk density data. It is probably because peculiar soil structure in each field could affect the hydraulic properties more than the soil texture. Simulation results also indicated that soil moistures are much different even if they are located in neighbors (<5 km). We concluded that combination of these two databases is useful for estimating soil hydraulic parameters and to predict soil moisture condition in arbitrary agricultural lands.     

Guidelines for soil conservation towards integrated basin management for sustainable development: A new approach based on the assessment of soil loss risk using remote sensing and GIS

Soil suspension in the Cidanau River of western Java, Indonesia, has increased recently, perhaps because of rapid environmental change in this watershed region. The objectives of this research are to assess soil loss risk using remote sensing and GIS and to develop effective guidelines for soil conservation in this watershed. To assess soil loss risk, a new soil loss model based on Universal Soil Loss Equation (USLE) was applied, in which C factor (crop management factor) was estimated using the perpendicular vegetation index (PVI); this was computed with satellite remote sensing data and used to simulate soil loss risk. The simulation showed that areas with highest risk of soil loss are on northern- and southern-facing hillsides with poor vegetation. Guidelines for soil conservation in the watershed were proposed: under these guidelines soil-loss risk is managed by evaluating the effectiveness of contour farming, belt farming, and mulch farming. Some recommended measures for soil conservation are as follows: (1) Green vegetation cover should be preserved as much as possible. (2) Vegetation coverage must be increased by forestation in steep sloped areas. (3) Belt farming and contour farming are recommended in areas with slopes under 100%, and mulch farming (more than 50% ground cover mulching is recommended) is desirable in areas with slopes over 100% and without green cover.     

Reduction of runoff and soil loss over steep slopes by using vetiver hedgerow systems

Vetiver hedgerow system has potential for reducing runoff and soil loss especially on steep slope areas, but the dynamics of these reductions are not fully understood. This research was conducted to determine reduction in runoff and soil loss by vetiver hedgerow system. Vetiver hedgerow systems with three vertical intervals of hedgerow were tested on three land slopes and compared with the case without hedgerow for six simulated rainfall amounts. The vetiver hedgerows reduce runoff volume and soil loss by 31–69 and 62–86 %, respectively compared to the case without vetiver hedgerow. Runoff volume increases with rainfall amount, and hence increases soil loss. Therefore soil loss increases with land slope, runoff volume, rainfall amount, and vertical hedge interval. Two final equations for estimating soil loss are presented in this study. The first equation contains parameters of runoff volume, land slope, and vertical hedge interval, while the second equation contains rainfall amount instead of runoff volume. The correlation coefficients between estimated soil losses and the experimental data in this study and in the literatures were found to be 0.94 and 0.90 for the first and second equations, respectively.     

Influence of rotation system on siderophere-producing microorganism(SPM) in rhizosphere soil of southern China

Soil siderophores are important for crop growth,benefit ferric iron absorption of root,and are affected by cropping patterns.The objective of this study was to evaluate the quantity of siderophores in soil of 2 continuous crop rotation patterns over 30 years in Anren country,China.Quantity and siderophore-producing capability of microorganisms in rice-riceoilseed rape(DDY)rotation and rice-rice(DD)rontinuous cropping rhizosphere soil were tested and analyzed by chrome azurol S method.Isolated strains were used to identify siderophore-producing microorganism(SPM)by PCR amplification and DNA sequencing.Results showed that 9 siderophore-producing bacteria strains were isolated from DDY rhizosphere soil while 7 strains were identified from DD rhizosphere soil.The mean solubility index which representing siderophore-producing capability of strains was 3.05.PCR amplification results indicated that bacterial were the major SPM in soil.This research indicates that crop rotation systems could drive microorganisms to produce siderophores and enrich them in bacterial communities.     

影响丹东地区水稻产量水平的因素及解决对策

土壤肥力降低,渗透性差;水稻生育时期降雨偏多,低温寡照;品种抗性不足,品种多乱杂;病虫鼠害严重等因素限制了丹东地区水稻产量的提高。针对影响丹东地区水稻农业生产的限制性因子,提出增加农业投入;改良土壤,培肥地力;改革品种布局;综合防治病虫鼠害;加强新品种的引进和开发等相应对策,以提高水稻产量。     

Nutrient Dynamics

Summary

Environmental concerns currently trigger the development of more sustainable soil fertility management strategies. It appears that effective sustainable practices are those that enhance natural soil processes. Soil processes include the decomposition of residues and mineralization of organic matter, nitrogen fixation, nitrification, nitrate leaching, denitrification and sulfur reduction. Natural soil processes also include less well-understood interactions, namely, those leading to the dissolution of minerals by organic acids, as well as rhizospheric and mycorrhizospheric interactions. Plants, associated with arbuscular mycorrhizal symbionts, supply and distribute carbon and energy, sustaining most of the biotic mechanisms responsible for nutrient release from soil, and maintaining organic pools of nutrients. Among these pools, the microbial biomass and fine roots pools, with their very fast turnover time, are particularly important as they can maintain large amounts of nutrients in very labile form and, therefore, increase soil fertility. Agricultural soil systems are very dynamic and are characterized by large spatial and temporal variations, which are largely driven by plant development. In addition, nutrient dynamics in agricultural soil systems seem particularly influenced by temperature, moisture, and nitrogen and phosphorus fertilization. Nitrogen losses from soil are reduced in systems where nitrogen release corresponds to plant demand. Biological nitrogen fixation is a sound way to input nitrogen in cropping systems. Phosphorus losses can be reduced through increased reliance on the arbuscular mycorrhizal symbiosis of crops. Soils are diverse and complex systems, which, furthermore, respond to increasingly unpredictable climatic variations. Optimal agricultural soil management is a moving target and, hence, a challenging goal that will never be totally reached.     

大豆连作减产主要障碍因素的研究：Ⅱ.连作大豆土壤有害生物的障碍效应

在田间条件下对土壤进行灭菌,施肥和灌水试验,其结果表明,土壤中所存在的以大豆生长为最佳生存条件的有害生物,对大豆生长发育有重大不良影响,连作较非连作土壤生长的大豆生物量减少了７．２６％－１４．５２％,株高降低了１１．６％－１７．２６％,茎粗减少了１４．６３％－２１．９５％,叶面积减少了１０．４２％－１８．７０％,最终导致收获期减产１２．１９％－１４．５９％,用一个大气压湿热灭菌法对大豆连作土壤进行     

西藏青稞产区土壤和籽粒硒含量调查研究

为明确西藏青稞产区土壤和籽粒硒含量及两者之间的关系,对西藏青稞主产区80个地点的青稞籽粒和土壤进行取样调查,研究不同青稞产区土壤全硒含量、有效硒含量和青稞籽粒硒含量及其成因。结果发现,西藏青稞产区土壤全硒含量范围在0.026～0.432 mg·kg^-1,平均值为0.180 mg·kg^-1;根据土壤全硒含量分类标准,缺硒土壤占49%,硒适量土壤占33%,富硒土壤占18%,富硒土壤主要分布在雅鲁藏布江以南地区。土壤有效硒含量范围在0.001～0.059 mg·kg^-1,平均值为0.013 mg·kg^-1。青稞籽粒硒含量范围在0～0.098 mg·kg^-1,平均值为0.011 mg·kg^-1;根据籽粒硒含量分类标准,其中90%属于硒缺乏。青稞主产区土壤全硒含量与土壤有效硒含量之间及二者与青稞籽粒硒含量之间均呈显著正相关关系,说明土壤全硒和有效硒含量可作为衡量青稞富硒潜力的有效指标。土壤有效硒每增加0.01 mg·kg^-1,籽粒硒含量增加0.014 4 mg·kg^-1。本结果有助于西藏富硒土壤资源的合理开发、富硒青稞等农作物生产。     

Managing Soil Fertility Decline

Summary

Soil fertility is defined in terms of the ability of the soil to maximize plant productivity, often within economic constraints. A decline in natural soil fertility seems to have occurred over all civilizations. Overgrazing and deforestation are the two most important factors affecting global soil degradation. Nutrient losses from agricultural systems are broadly divided into losses through volatilization, losses from leaching, losses due to product removal, losses to non-labile soil pools and losses from various forms of erosion. Rapid declines in soil fertility are associated with large demands for food due to expanding population, nutrient mining of agricultural areas with concomitant shifts of produce to cities, and intensification of agricultural activities without proper regard for long-term maintenance of fertility by application of fertilizers, recycling of organic wastes, liming to combat acidification, fallowing, rotations and prevention of large scale soil erosion. Agricultural policy has often encouraged soil fertility decline and soil degradation. In the future, agricultural scientists must have major inputs into the development and implementation of policy.     

不同耕作方式对辽西褐土物理性状及玉米根系分布的影响

通过连续3年大田试验,对旋耕、翻耕、深松3种耕作方式下的土壤物理性质、玉米根系分布和产量进行测定。结果表明,与翻耕和旋耕相比,深松显著增加了玉米田土壤耕层厚度和降低了犁底层厚度。在中下层土壤,深松还降低了土壤紧实度和容重,改善了土壤的孔隙状况,有利于玉米根系向下生长,使得中下层土壤的玉米根系不仅更丰富,而且占总根系量的比例也更高,最终提高了玉米产量。本研究表明,深松耕作有利于改善辽西褐土区土壤结构和促进玉米生长。