重力勘探地形改正最大半径的选择

重力勘探地形改正半径偏小,会降低资料的可信度;地形改正半径过大,则会造成人力、财力的浪费。通过地形改正数学物理模型的建立,提出了地形改正最大半径的选择方法。      

Application of the Haug model for process design of petroleum hydrocarbon-contaminated soil bioremediation by composting process

The main scope of this work is applying an aerobic composting model for remediation of petroleum hydrocarbon-contaminated soil. For this purpose, the reaction kinetics was integrated with the mass and energy balances over the composting system. Literature pilot scale data for bioremediation of diesel oil-contaminated soil was used for model validation. Comparisons of simulation results with experimental data for diesel concentration and oxygen concentration showed good agreement during the remediation process. With validated model for bioremediation of diesel oil-contaminated soil, the influence of amendment type, bulking agent, amendment/soil ratio, bulking agent/soil ratio, moisture content and airflow rate were investigated on diesel biodegradation. The simulation results showed that maximum degradation of diesel occurred in the presence of yard waste as amendment. Furthermore, addition of bulking agent (wood chips) increased the diesel degradation about 6 %. In presence of yard waste as amendment and wood chips as bulking agent, the optimal values for maximum remediation were amendment/soil ratio (2.5 kg kg^?1), bulking agent/soil ratio (2.25 kg kg^?1), initial moisture content (62.5 %) and airflow (0.520 m³ day^?1 kgBVS^?1).     

江汉平原富硒冷浸田的利用模式

江汉平原是中国四大粮仓之一,拥有约69万公顷富硒土壤,大部分为冷浸田,如何利用富硒冷浸田种植富硒水稻是当前亟需研究解决的重大实际问题.以排水整改、强化施硒肥和排水整改后施硒肥3种模式开展了江汉平原富硒冷浸田的大田种植实验.结果表明,在排水整改模式下,排水降低了冷浸田地下水位,提升了土壤的通气性和氧化还原电位,加快了土壤中有机结合态硒向可利用态硒转化,使得土壤可利用态硒比整改前提高25.0%;促进了水稻对硒的吸收,使得水稻根系和籽实中硒含量比整改前分别增加20.6%和8.3%,仅茎干中硒含量无明显变化.在强化施硒肥模式下,每亩施加80 kg硒肥后土壤可利用态硒比施肥前提高41.7%;极大地促进了水稻对硒的吸收,使得水稻根系、茎秆、籽实中硒含量比施肥前分别提升79.4%、37.1%、25.0%.在冷浸田排水整改后每亩施加80 kg硒肥模式下,土壤可利用态硒含量和水稻根系、茎干、籽实中硒含量分别增加50.0%和41.8%、46.1%、47.9%.总之,上述3种利用模式均可提高土壤可利用态硒含量,有利于水稻对土壤硒的吸收,能够显著提高水稻籽实中硒含量;冷浸田排水整改后强化施硒肥利用模式效果最佳.      

石灰岩含水介质中苯系物（BTEX） 生物可降解性判识

    岩溶含水系统遭受石油烃污染的环境问题十分普遍。相对于多孔含水介质,石油烃BTEX在石灰岩含水介质中的生 物可降解性还不确定。为此,本研究开展了BTEX在石灰石和岩溶地下水介质中的静态微元体实验。经过77天的实验检测 分析,结果表明：（1） BTEX化合物在可利用电子受体溶解氧或硝酸盐存在条件下具有生物可降解性;（2） 向系统中补充 电子受体硝酸盐,具有促进生物降解的作用,其对BTEX的去除率可高达94%;（3） 未发现补充硫酸盐能够促进BTEX生物 可降解性;（4） 甲苯和二甲苯容易被生物降解,但苯的去除具有一定的难度。     

Effects of biochar-based fertilizers on nutrient leaching in a tobacco-planting soil

Acta Geochimica - Biochar is a soil amendment for increasing soil quality and decreasing nutrient leaching. However, there is little information on the impact of biochar-based fertilizer (BF) on...     

Anthrosols in Iron Age Shetland: Implications for arable and economic activity

The soils surrounding three Iron Age settlements on South Mainland, Shetland, were sampled and compared for indicators of soil amendment. Two of the sites (Old Scatness and Jarlshof) were on lower‐lying, better‐drained, sheltered land; the third (Clevigarth) was in an acid, exposed environment at a higher elevation. The hypothesis, based on previous regional assessments, soil thicknesses, and excavations at Old Scatness, was that the lowland sites would have heavily fertilized soils and that the thin upland soil would show little if any amendment. Our findings indicate that the Middle Iron Age soils at Old Scatness had extremely high phosphorus levels, while the soil at Jarlshof had lower levels of enhancement. At Clevigarth, where charcoal from the buried soil was 14C dated to the Neolithic and Bronze Age, there was no evidence of arable activity or soil amendment associated with the Iron Age phases of settlement. These observations indicate that not all sites put the same amount of effort into creating rich arable soils. The three sites had very different agricultural capacities, which suggests the emergence of local trade in agricultural commodities in Iron Age Shetland. © 2008 Wiley Periodicals, Inc.     

Do NaOH amendments control the chemical and biological production of sulphate in aerated mine lake sediments?

. The aim of our work was to evaluate the effects of NaOH addition to aerated mine lake sediment on the production of sulphate and to discriminate between the spontaneous chemical oxidation and microbially mediated oxidation of sulphurous compounds. From the viewpoint of practical applicability, we asked ourselves the following key questions: (1) does NaOH addition control the chemical and biological oxidation of sulphate in aerated sediment? and (2) can NaOH be used in practice to control sulphate production? From our experimental results, we can conclude that (1) NaOH amendment controls the rate of both chemical (enhancement) and biological (suppression) processes and (2) NaOH amendment under practical conditions can not be applied to reduce the total amount of produced sulphate from aerated sediment.     

Amending highly weathered soils with finely ground basalt rock

Surface (0–10 cm) samples of 7 soils from tropical coastal Queensland were incubated at room temperature and at field capacity with finely ground (<150 μ) basalt rock for 3 months. The amendment was applied at 0, 1, 5, 25 and 50 t/ha to cover situations of moderate application rates to that where the amendment might be banded to produce high local concentrations. Having an abrasion pH of about 9, the amendment was able to reduce both active acidity (as estimated by an increase in soil pH) and reserve acidity (reduction in % Al saturation of the CEC). Increases in soil pH resulted in increased CEC, depending on the variable charge nature of each soil, accompanied by increases in exchangeable Ca, Mg, and K supplied by the basalt. The amounts of basic cations converted to exchangeable form constituted only a fraction of the amounts applied. Thus the cations held in reserve ensure that the effect of cation enrichment will be prolonged. In some soils phosphate sorption was significantly reduced by crushed basalt application. Furthermore, ‘available’ P as measured by extraction with 0.005 M H₂SO₄ was increased. These effects appear to be due to the release of silicate from the basalt as well as modest amounts of phosphate in the rock. Three extractants commonly used for estimating Si availability in sugarcane production indicated that all 7 soils contained sub-optimal levels of the element. Application of crushed basalt rock increased extractable Si levels above what is considered sufficient for this crop. The incubated soils were placed in columns and leached with the equivalent of 2750-mm (average wet season) rainfall. Re-analysis showed that the favourable chemical soil properties imparted by the amendment were retained. These results add further support to the contention that the effects of amelioration will continue for some time.     

Immobilization of phosphorus in sewage sludge using inorganic amendments

Sewage sludge contains large amount of water-soluble phosphorus, which is prone to runoff loss when sewage sludge is land applied. Phosphorus export from sewage sludge is an important cause for water eutrophication. Immobilization of phosphorus before sewage sludge land application seems necessary. In this study, three amendments including red mud (RM), lime and mixture of RM and lime were employed to immobilize phosphorus in fresh sewage sludge. It was found that phosphorus was effectively controlled by RM, lime and mixture of RM and lime. Sequential chemical extraction results indicate that the RM amendment transformed H₂O-P in the sewage sludge into the NaOH-P, while the lime amendment transformed H₂O-P in the sewage sludge into the HCl-P. Such transformations in phosphorus fractions would have little influence on phosphorus availability but would retard and reduce potential phosphorus loss following sewage sludge was land applied.     

Effects of biochar and bio-fertilizer on yield and qualitative properties of soybean and some chemical properties of soil

This study attempted to examine the effects of biochar amendment together with bio-fertilizer on soybean yield and its qualitative properties, as well as a few chemical properties of soil through a factorial randomized complete block design at three replications in east of Golestan Province (Iran) during 2014. The two factors under study included the following: (1) biochar amendment (in four levels of 0, 2.5, 8, and 16 tons per hectare), (2) bio-fertilizer containing phosphorus and sulfur growth-promoting rhizobacteria (in two levels of inoculation and non-inoculation) applied through foliar feeding. The results of analysis of variance indicated that interactions of biochar amendment and bio-fertilizer on harvest index and grain yield were significant (p ≤?0.01). According to the results of this study, the highest harvest index and oil content were 56.9, and 17.7%, respectively, in the treatment of 8 tons per hectare biochar and inoculation with bio-fertilizer. The lowest harvest index and the lowest oil content were in the control treatment. The interaction of biochar and bio-fertilizer on bulk density and cation exchange capacity was significant (p ≤?0.01). The results of this study demonstrated that biochar affected the amount of residual nitrogen in the soil after harvest, cation exchange capacity (CEC), acidity (pH), and electrical conductivity (EC). The highest grain yield (3440 kg/ha) was in the 8-ton biochar treatment with inoculated bio-fertilizer. Our study concludes that the biochar and bio-fertilizers can improve grain yield of soybean till 51% relative to the control.     

Reduction of phosphorus release from high phosphorus soil by red mud

The high phosphorus levels cause the release of phosphorus from soils, thereby increasing the potential for phosphorus export to adjacent water bodies. The loss of phosphorus from soils to surface waters is a major source of water quality impairment. Therefore, soil phosphorus immobilization seems necessary. In this study, red mud (RM) was employed to immobilize phosphorus in a typical agricultural soil. It was found that phosphorus was effectively immobilized by RM. Batch leaching experiments showed that RM reduced phosphorus release from 14.38 to 2.56 mg/kg when soil was amended with 1% RM. Column leaching experiments showed that RM reduced the total amount of phosphorus released from 36.73 to 18.79 mg/kg during the investigated period. Sequential chemical extraction results indicated that RM amendment transformed H₂O-P into more stable fractions. The results suggested that application of RM amendment to soils could significantly immobilize soluble phosphorus, reducing phosphorus release to the environment.     

Comparative efficacy of brown, green and red seaweeds in the control of root infecting fungi and okra

The effect of soil amendment by brown, green and red seaweeds was studied in controlling the root rot infecting fungi of okra seedlings in the greenhouse. The soil amendment with seaweeds Stokeyia indica, Padina pavonia (brown), Solieria robusta (red), at 1% w/w redaced Macrophomina phaseolina, Rhizoctonia solani and Fusarium solani infection on okra roots. Codium iyengarii (green) at 0.5 % w/w was effective against F solani, while at 1% w/w was found phytotoxic. S. robusta showed better control of F. solani infection when used with Pseudomonas aeruginosa than either used alone. S. robusta produced better plant height and fresh weight of shoot than P. aeruginosa. Results of the present study suggest that the use of brown seaweeds S. indica and P. pavonia alone and S. robusta alone or in combination with P. aeruginosa have great potential to control root-infecting fungi of okra with enhancement of plant growth. These seaweeds alone or in combination with P. aeruginosa may be utilized as biological control of root infecting fungi of okra.     

在基于数字填图系统的1：25万区域地质调查修测中前人地质资料的利用与数据采集

1：25万区域地质调查修测的核心任务是挖掘、利用前人资料和对前人资料的二次开发。在1：25万玉林市幅数字地质填图试点的过程中．总结出一套基于数字填图系统的前人地质资料利用与数据采集的工作方法。其工作流程和工作步骤可分为6个阶段：①前期准备阶段;②室内地质资料录八阶段;③野外数字地质调查阶段;④室内资料整理阶段;⑤图件编制阶段;⑥成果提交阶段。该工作方法与传统的地质调查方法相比,提高了地质调查的工作效率和质量,已基本上达到了在1：252万区调修测区推广应用的“实战性”要求。     

Chemical variables influencing microbial properties in composted tannery sludge-treated soil

Repeated applications of composted tannery sludge to arable soils have the potential to greatly alter soil chemistry and thus potentially influence the soil microbial community over time. This study performed multivariate analyses using the data of soil microbial biomass, respiration, and enzymes activities obtained during 5 years (2010–2014) in a long-term experiment with composted tannery sludge amendment. The correlation between the soil microbial and chemical properties, via the analysis of similarity matrices, revealed calcium as the main single factor influencing the microbial properties, in 2010 and 2011. Afterward, chromium was the most important chemical variables driving the microbial properties in 2012, 2013, and 2014. The non-metric multidimensional scaling demonstrated that the soil microbial properties changed with composted tannery sludge application from 2010 to 2014. Multivariate analysis from soil microbial data with composted tannery sludge amendment, during 5 years, showed calcium and chromium as being the most significant variables influencing the soil microbial properties in composted tannery sludge-treated soil.     

Immobilization of Cd,Zn and Pb in sewage sludge using red mud

Sewage sludge is an inevitable end by-product of sewage treatment. Land application provides a cost-effective alternative for sewage sludge disposal. However, sewage sludge contains heavy metals that may limit its application. In this work, red mud was employed for the immobilization of heavy metals in sewage sludge. The effect of red mud amendment on heavy metal immobilization was evaluated using Toxicity Characteristic Leaching Procedure (TCLP) method. The TCLP results showed that the immobilization efficiency of Cd, Zn and Pb was 100, 92, and 82%, respectively, when sewage sludge was mixed with 10% red mud. Tests carried out in leaching columns demonstrated that heavy metal concentrations in the leachate of 10% red mud amended sludge were lower than those of the unamended sludge. Moreover, red mud decreased plant available heavy metal (Cd, Zn and Pb) content from 18.1, 17.2 and 14.6% to 6.9, 11.4 and 7.6%, respectively. Sequential chemical extraction experiments showed that after sludge was amended with 10% red mud, exchangeable fraction was reduced and iron and manganese oxides fraction was increased. Red mud amendment can effectively immobilize Cd, Zn and Pb in sewage sludge before land application.     

潜水完整井抽水时水跃值研究

针对艾连别格尔水跃值经验公式,用最小二乘法对其进行修正。通过实例对修正前后两公式进行验证,得出如下结论：艾连别格尔的水跃值经验公式过于保守,误差很大,而经最小二乘法修正后的公式能更好的反应实际情况,误差明显减小。说明修正后的公式更适用于实际工程。     

Microbial community changes in contaminated soils in response to phenanthrene amendment

Leachate and reclaimed wastewater have become the important sources of polycyclic aromatic hydrocarbons in soils. However, the information on bioremediation of leachate and reclaimed wastewater-contaminated soils is still lacking. Identification of changes in microbial structure or of enriched genera related to biodegradation could aid identification of particular organisms or consortia capable of degrading polycyclic aromatic hydrocarbons in these contaminated soils. In this study, terminal restriction fragment length polymorphism, coupled with 16S Ribosomal ribonucleic acid clone library analysis, was applied to investigate the composition of bacterial community in leachate-contaminated soil or grassland soil irrigated reclaimed wastewater and the response to phenanthrene amendment. Results showed that phenanthrene amendment had significant but different impacts on microbial community structure, dependent on soil source. Several greatly enriched terminal restriction fragments with phenanthrene biodegradation were identified. Moreover, genus rhizobacteria, possibly linked to phenanthrene biodegradation, was firstly reported in this study. This work might provide some new insights into bioremediation of polycyclic aromatic hydrocarbons-contaminated soils.     

Synthesis of biochar from sugarcane filter-cake and its impacts on physiological performance of lettuce (<Emphasis Type="Italic">Lettuce sativa</Emphasis>) grown on cadmium contaminated soil

Soil contamination with cadmium has become major concern all over the world because of its adverse impacts on ecosystem health and agricultural land. Soil amendment with biochar may have varied effects on physical and chemical properties of soil. The objective of the study was to explore the impact of sugarcane filter-cake biochar on physiological performance and growth of lettuce in an aged soil. Four different doses (0, 1.5%, 3%, and 5%) of biochar were used in the soil and conditioned for 1 month. After this, lettuce seedlings were grown in the soil. The results showed that the biochar treatment improved the fresh and dry biomass of leaves and roots as well as plant height while diminished the bioavailability of cadmium from the soil. As compared to control, biochar significantly enhanced the chlorophyll content in lettuce leaves. Due to the biochar amendment, the oxidative stress decreased in lettuce shoots over the control. As compared to control, concentration of cadmium in lettuce significantly decreased after the application of biochar. It was concluded that biochar could mitigate the toxicity of cadmium in lettuce by altering the biochemical and physiological processes in cadmium contaminated soil.     

深基坑“T”型地下连续墙应力监测分析

根据上海某工程深基坑“T”型截面地下连续墙安全监测数据,修正温度变化对振弦式钢筋计应力测值的影响,通过计算分析地连墙不同截面的应力规律并计算对应的弯矩及轴力值,得出了一些结论和建议,对类似工程有一定借鉴作用。