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1.
The problem of soil degradation through alkalinization/salinization in an irrigated area with a semi-arid climate was examined in the inner delta of the Niger River, Mali, by the study of groundwater hydraulics and hydrochemistry in an area recharged by irrigation water. On the basis of data analysis on various scales, it is concluded that the current extent of the surface saline soils is due to a combination of three factors: (1) the existence of ancient saline soils (solonchaks) resulting from the creation of a broad sabkha west of the former course of the Niger River, now called the Fala of Molodo. These saline crusts were gradually deposited during the eastward tilting of the tectonic block that supports the Niger River; (2) the irrigation processes during the recent reflooding of the Fala of Molodo (river diversion in 1950). These used very poorly mineralized surface water but reintroduced into the alluvial groundwater system – generally of a low permeability (K=10–6?m?s–1) – salts derived from the ancient solonchaks; and (3) the redeposition of the dissolved salts on the surface due to the intense evapotranspiration linked to the present Sahelian climate. In this context, only efficient artificial draining of subsurface alluvial groundwater can eliminate most of the highly mineralized flow and thus reduce the current saline deposits.  相似文献   

2.
This research describes application of laccase from white-rot fungi (polyporus) to remove dichlorodiphenyltrichloroethane in soil. The degradation kinetics of dichlorodiphenyltrichloroethane in soil was also investigated by laboratory batch experiments. The results showed that laccase from white-rot fungi can effectively degrade dichlorodiphenyltrichloroethane and the degradation of total dichlorodiphenyltrichloroethane (the sum of the four dichlorodiphenyltrichloroethane compounds in a sample) was pseudo-first-order kinetics. The residues of almost all the dichlorodiphenyltrichloroethane components and total dichlorodiphenyltrichloroethane in soils treated with laccase decreased rapidly during first 15 days and then kept at a stable level during next 10 days. The residues of total dichlorodiphenyltrichloroethane in soils with different dosages laccase decreased by about 21–32 %, 29–45%, 35–51 % and 36–51 % after 5, 10, 15 and 25 days of incubation, respectively. The half-life of total dichlorodiphenyltrichloroethane in soils with different dosages laccase ranged from 24.75 to 41.75 days. The residues of total dichlorodiphenyltrichloroethane in three different types of soils decreased by 25–29 %, 39–43 %, 44–47 % and 47–52 % after 5, 10, 15 and 25 days of incubation with laccase, respectively. The half-life of total dichlorodiphenyltrichloroethane in different types of soil ranged from 24.71 to 27.68 days. The residues of total dichlorodiphenyltrichloroethane in soils with different pH levels decreased by 18–24 %, 29–39 %, 36–39 % and 39–50% after 5, 10, 15 and 25 days of incubation with laccase, respectively. The half-life of total dichlorodiphenyltrichloroethane ranged from 25.63 to 36.42 days. Laccase can be an efficient and safe agent for remediation of dichlorodiphenyltrichloroethane-contaminated soil.  相似文献   

3.
盐渍土是江苏沿海地区开发建设需关注的地质环境问题之一。本文系统采集5 m以浅的土样,开展易溶盐试验,研究了江苏沿海盐渍土分布规律、盐渍化程度及影响因素。研究结果表明:全区盐渍土平行于海岸线分布;以中、弱盐渍土为主,强盐渍土零星分布。受沉积环境、气候、水文地质条件、人类活动等共同影响,盐渍化程度空间差异明显。平面上,盐渍化程度呈北强南弱、向海岸线方向延伸有逐渐增强的趋势,强盐渍土分布于连云港黏性土区,岩性、地下水矿化度为主导影响因素。垂向上,表层普遍积盐,连云港地区分带不明显,大丰和南通地区自地表而下可划分为三带,表层土蒸发积盐、中层盐动态变化、下层土饱水盐稳定,地下水位、土体结构为主导影响因素。随着沿海大开发的快速推进,为防止次生盐渍化问题,需关注地面沉降导致的地面高程损失诱发海水入侵加重表层土盐渍化,工程建设中可设置隔离层截断高矿化度地下水的毛细作用。  相似文献   

4.
The main objective of this study is to assess the land degradation risk of cultivated land in El Fayoum depression. The physiographic map of the depression was produced by using remote sensing and land surveying data. The depression comprises lacustrine plain, alluvial–lacustrine plain, and alluvial plain representing 12.22%, 53.58%, and 34.20% of the total area, respectively. The soil, climate, and topographic characteristics of the depression were extracted from land surveying, laboratory analyses, digital elevation model, and available reports. A simple model was designed to employ these data for assessing the chemical and physical risk of land degradation using Arc-GIS 9.2 software. The obtained results indicate that severe risk to chemical and physical degradation affect 54.15% and 29.23% of the depression, respectively. The current status of soil salinity, sodicity, and water table indicate that most of lacustrine and alluvial–lacustrine soils are actually degraded by salinization, sodification, and waterlogging. The results of degradation risk and the actual hazard indicate that the human activities are not sufficient to overcome the degradation processes in the most of the depression (80. 22%). Moreover, a negative human impact affects 26.29% of the area mostly in the alluvial plain. Great efforts related to the land management are required to achieve the agriculture sustainability.  相似文献   

5.
The time at which deserts established their current arid or hyper-arid conditions remains a fundamental question regarding the history of Earth. Cosmogenic isotope exposure ages of desert pavement and welded, calcic–gypsic–salic Reg soils that developed on relatively flat alluvial surfaces ～2 Ma ago in the Negev Desert indicate long geomorphic stability under extremely dry conditions. Over a short interval during their initial stage of development between 1–2 Ma, these cumulative soils are characterized by calcic soils reaching maximum stage III of carbonate morphology. This interval is the only period when calcic soil horizons formed on stable abandoned alluvial surfaces in the southern Negev Desert. Since ～1 Ma pedogenesis changed toward more arid soil environment and the formation of gypsic–salic soil horizons that were later followed by dust accumulation. The dichotomy of only moderately-developed calcic soil (stages II–III) during a relatively long time interval (105–106 years) indicates an arid environment that does not support continuous development but only occasional calcic soil formation. The very low δ18O and relatively high δ13C values of these early pedogenic carbonates support soil formation under arid climatic conditions. Such an environment was probably characterized by rare and relatively longer duration rainstorms which occasionally allowed deeper infiltration of rainwater and longer retention of soil moisture. This, in turn enabled the growth of sparse vegetation that enhanced deposition of pedogenic carbonate. At ～1 Ma these rare events of slightly wetter conditions ceased and less atmospheric moisture reached the southern Negev Desert leading to deposition of soluble salts and dust deposited in the soils. The combination of long-term hyperaridity, scarcity of vegetation and lack of bioturbation, salts cementation, dust accumulation and tight desert pavement cover, has protected the surfaces from erosion forming one of the most remarkably stable landscapes on Earth, a landscape that essentially has not eroded, but accumulated salt and dust for more than 106 yr.  相似文献   

6.
为揭示冲积与湖积成因土壤镉的吸附特征,以安徽省当涂县冲积成因的江心洲和冲积、湖积成因的大陇乡根际土壤为研究对象,开展土壤镉的等温吸附实验和吸附动力学实验.等温吸附实验结果表明,冲积土壤镉的吸附量（S）、等温吸附常数（K）和固液分配系数（Kd）均较湖积土壤明显偏大,显示冲积土壤对镉的吸附能力较湖积土壤强;吸附动力学实验表明,冲积土壤的最大吸附量、平衡吸附量均较湖积土壤大,吸附速率也明显偏大,尤其在吸附实验早期更为显著;等温吸附常数K和平衡吸附速率Vb与土壤理化性质的分析表明,土壤pH是造成研究区土壤镉吸附能力差异的主要原因,其次为物理性粘粒含量;土壤pH是影响研究区冲积土壤镉吸附能力的主要因素;湖积土壤镉的吸附能力受土壤pH、有机质含量、Cd含量、物理性粘粒含量等因素的综合影响.研究对于揭示Cd在水土系统的迁移转化规律以及土壤Cd的污染防治具有重要的指导意义.   相似文献   

7.
Phosphorus (P) desorption characteristics may be altered due to the biosolids decomposition during the incubation period. In our previous work we studied the phosphorus release kinetics in biosolids-amended calcareous soils with no prior incubation. The objectives of this work were (1) to assess the phosphorus desorption behavior in soils as influenced by biosolids after 5 months of incubation and (2) to evaluate the influences of six levels of the biosolids on phosphorus availability and salinity of soil. The results showed that the biosolids addition significantly increased the soil available P and salinity. The P availability and salinity of the soils increased as level of the biosolids application increased. However, there was no significant difference between some application rates for some soils. The results indicated that the incubation can affect the factors controlling the P release rate. Also, the results showed that the soil organic matter negatively affected the P desorption rate in the biosolids-treated soils.  相似文献   

8.
《Applied Geochemistry》2006,21(6):964-976
Hopanoids have been widely used as characteristic biomarkers to study inputs of bacterial biomass to sediments because they are preserved in the geologic record. A limited number of studies have been performed on hopanoid biomarkers in soils. The present study examined the distribution and potential preservation of hopanoids in soils that are developed under different climatic conditions and varying vegetative inputs. Solvent extraction and sequential chemical degradation methods were employed to extract both “free” and “bound” hopanoids, from three grassland soils, a grassland–forest transition soil, and a forest soil from Western Canada. Identification and quantification of hopanoids in the soil samples were carried out by gas chromatography–mass spectrometry. Methylbishomohopanol, bishomohopanol and bishomohopanoic acid were detected in all solvent extracts. The base hydrolysis and ruthenium tetroxide extracts contained only bishomohopanoic acid at a concentration range of 0.8–8.8 μg/gC and 2.2–28.3 μg/gC, respectively. The acid hydrolysis procedure did not release detectable amounts of hopanoids. The solvent extraction yielded the greatest amounts of “free” hopanoids in two of the grassland soils (Dark Brown and Black Chernozems) and in the forest soil (Gray Luvisol). In contrast, the chemical degradation methods resulted in higher amounts of “bound” hopanoids in the third grassland soil (Brown Chernozem) and the transition soil (Dark Gray Chernozem), indicating that more hopanoids exist in the “bound” form in these soils. Overall, the forest and the transition soils contained more hopanoids than the grassland soils. This is hypothesized to be due to the greater degradation of hopanoids in the grassland soils and or sorption to clay minerals, as compared to the forest and transition soils.  相似文献   

9.
It is generally accepted that the compositions and properties of soil organic matter (SOM) are influenced by many factors. In order to reveal the effects of soil texture on characteristics and dynamics of SOM and its sub-fraction, humic acid (HA), along two soil profiles, a yellow soil profile and a purplish soil profile, under the same climate and vegetation conditions were determined. Results indicate that the decomposition and humification degrees of SOM and HA of the purplish soils are higher than those of the corresponding yellow soils indicated by A/O–A ratios of HAs, TOCs and HA yields of bulk soil samples, nevertheless, the development degree of the purplish soil is lower than that of the yellow soil. The variations of E4/E6 ratios of HAs along the soil profiles indicate the overall molecular sizes of HAs decreased downward along the soil profiles. A/O–A ratios of HAs decreased downward along both the soil profiles indicate that humification processes decrease downward along both the soil profiles. Leaching of SOM shows significant effects on the distribution and characteristics of HAs in the yellow soil profile but the purplish soil profile, which is consistent with the higher hydrophobicity of HAs in purplish soils, shows that the distribution characteristics of SOM along the soil profiles are a complex result of the combination of soil texture and characteristics of SOM itself. The remarkably different sand contents are concluded tentatively as one of reasons to the different distributions and dynamics of HAs along the soil profiles, however, to profoundly understand the evolution and transport of SOM along soil profiles needs more researches.  相似文献   

10.
Average relative stream channel migration rates of .21 meters per year (.72 feet per year) for saline tidal wetland stream channels, and .32 meters per year (1.04 feet per year) for freshwater tidal wetland channels were calculated for a 32 year period (1940 to 1972) using photogrammetric techniques. Saline wetland stream channels averaged higher indices of sinuosity, i.e., the ratio of total channel length to linear downstream distance (1.95), when compared with sinuosities of freshwater tidal channels (1.46). The difference is attributed to differences in vegetation types and consequent soil holding capacity between saline and freshwater tidal wetland environments. Saline channels become entrenched because the banks are supported by dense root systems, while freshwater tidal channels flow through a more homogenous substrate and behave much like channels which cross mud-flats in the intertidal zone. Higher average meander amplitudes (one-half the peak to trough distance of a given meander wave) for saline channels (171 meters) versus lower amplitudes for freshwater channels (114 meters) suggest that meander loops for saline channels are determined primarily by the erosional characteristics of stream banks and by other local factors rather than by hydrodynamic factors such as flow velocity or discharge. It has been stated that meander migration features do not occur in homogenous soil materials (Leopold, et al. 1964); the tendency of saline channels to form these features is attributed to differential erosion caused by variations in root system density. Conversely, the morphology of freshwater tidal channels is influenced by hydrodynamic factors including discharge, and is due to the existence of more homogenous materials, i.e., muddy soils devoid of extensive root systems. An analysis of ebb and flood discharge data arrived at for each tidal channel using existing tidal current velocity and upland discharge records supports the fact that relatively greater erosive forces occur in salt marsh than in fresh tidal marsh areas. A poor statistical correlation between rates of stream channel migration and hydraulic stream flow data such as velocity and discharge must be accepted with caution due to the method of approximating tidal discharge values. The correlation suggests that under normal tidal conditions both saline and freshwater tidal channels migrate little, if any, and thus represent an apparently balanced relatively low energy system. For this reason it is believed that most stream channel migration in both saline and freshwater wetlands occurs as a result of increased forces due to storms.  相似文献   

11.
An investigation of soil salinization was carried out in the Nanshantaizi area (Northwest China) with WET Sensor. This device can measure such soil parameters as bulk soil electrical conductivity, water content, and the pore water electrical conductivity that are important for soil salinization assessments. A distribution map of soil salinization was produced, and the factors influencing soil salinization and its processes were discussed in detail. The study shows that moderately salinized to salt soils are mainly observed in the alluvial plain, where groundwater level is high and lateral recharge water contains high salinity. Nanshantaizi is covered by slightly salinized soils. The soil salinization distribution estimated by WET Sensor is generally consistent with the actual levels of salinization. Soil salinity in Nanshantaizi is mostly of natural origin and accumulated salts could leach to deeper soils or aquifers by water percolation during irrigation. Groundwater evaporation, groundwater level depth and quality of recharge water are important factors influencing soil salinization in the alluvial plain.  相似文献   

12.
运用对映体分馏分析(EFA)与单体同位素分析(CSIA)技术研究了三唑类杀菌剂腈菌唑在4种不同种植年限茶园土壤中的对映体选择性降解规律。腈菌唑的降解符合一级反应动力学方程,半衰期为28.4~70.5 d。4种茶园土壤中均表现为(+)腈菌唑优先降解,并均有碳同位素富集,表明发生了显著的微生物降解。腈菌唑在茶园土壤中的降解半衰期和对映体比在50年茶园土中最小,显著低于100年、20年和2年茶园土壤(P<0.05)。降解半衰期与砂粒含量显著相关(P<0.05),对映体选择性与粉粒含量显著相关(P<0.05)。运用Rayleigh方程计算各土壤中腈菌唑的碳同位素富集因子,并建立生物降解评估模型。应用两种方法评估生物降解所得结果与总降解率趋势相同。  相似文献   

13.
With the increasing application of germanium (Ge) elements in modern industry, military and medical health industries, especially with the growing demand for Ge-rich agricultural products, the study of Ge-rich soil has become particularly important, but the enrichment pattern and control factors of Ge-rich soil are still not well understood due to the high dispersion and high migration of Ge-rich soil. In this paper, 495 surface soil (0–20 cm) and 149 deep soil (150–200 cm) samples were collected from the northern foothills of Dabie Mountain using a double-layer grid layout, and the spatial distribution and enrichment characteristics of Ge were studied by high-resolution method, and the controlling factors affecting the distribution of Ge-rich soil was analyzed by geo-statistics and spatial analogy. The results show an average Ge content of 1.34 mg/kg for the surface and 1.36 mg/kg for the deep soil. In the assessment grade classification of surface and deep soil for Ge, the abundant and sub-abundant grades account for 37.97% and 31.70%, respectively, covering 752 km2 and 634 km2. Surface Ge-rich regions are distributed in concentrated strips in the north-central part of the studied region, and there is no clear pattern in the spatial distribution of deep soils. In the areas under study, such as Fenlukou, Dingji, and Jiangjiadian, the surface soil is very rich in Ge and has a high enrichment factor, which is valuable for agricultural development. In surface soils, river deposits and shallow metamorphic rock parent materials have the highest content of Ge, while in deep soils, the highest content has been found in the parent material of moderately acidic rock. Both surface and deep soils have the highest Ge content in purple paddy soils and plain areas. The source of Ge in the soils of the study area is most influenced by the lithology of the soil-forming parent material, while the distribution of Ge in the surface soils is jointly influenced by pH, SiO2, TFe2O3, and Al2O3 in the soil. This study has implications for understanding the enrichment pattern of Ge in soil and its controlling factors as well as for the development of Ge-rich agricultural products.  相似文献   

14.
A laboratory investigation was carried out to examine the mechanism of arsenic (As) mobilization under flooded conditions (24 and 240 h) in 18 alluvial soils of Punjab, North–West India. Total dissolved As increased from a range of 3–16 μg L?1 (mean 9 μg L?1) to a range of 33–1,761 μg L?1 (mean 392 μg L?1) with the increase in flooding period from 24 to 240 h. The amount of As mobilization varied depending upon redox potential (pe) created by flooding conditions. After 24 h of flooded conditions, pe of soil water suspension ranged from ?1.75 to 0.77 (mean ?0.24). Increasing the flooding period to 240 h, pe of soil water suspension decreased in the range of ?4.49 to ?2.74 (mean ?3.29). Pourbaix diagram identified arsenate (HAsO4 2?) as predominant species in most of the alluvial soil–water suspensions under oxidized conditions, after 24 h of equilibration period, which ultimately transformed to arsenite (H3AsO3 0) after 240 h of anaerobic condition due to more reduced status. The solid phase identified was orpiment (As2S3). Identification of iron and manganese species in alluvial soil water suspension by Pourbaix diagram indicated decline in both soluble Fe2+ and SO4 2? concentration due to the formation of iron sulfide mineral phase after 240 h under anaerobic conditions. In these soils, decline in soluble Fe was also due to the precipitation of vivianite [Fe3(PO4)2·8H2O]. Elevated arsenic content and low pe value were measured in aquifers located in paddy growing fields comparative to aquifers of other sites. Large degree of variability in As concentrations was recorded in aquifers located at same sites. Thus, it is better to analyze each aquifer for their As content rather than to depends on the prediction on As content of neighbouring wells. The present investigation elucidates that flood irrigation practices in Punjab for growing paddy crop could induce the geochemical conditions favorable to mobilize arsenic from surface soils which could eventually elevate its content in the underlying shallow aquifers. Water abstracted from these aquifers by hand pumps or tube wells for drinking purposes could create hazards for local population due to loading with arsenic concentration above the safe limits. Thus, to avoid further contamination of shallow aquifers with arsenic, it is advisable to shift the flooded rice cultivation to other upland crops having lesser water requirement.  相似文献   

15.
The Pampa de Chaparrí (Pampa) in hyperarid northwest coastal Peru is an ideal area to study late prehispanic agricultural technology and production because irrigation canals and furrowed fields have been preserved since abandonment approximately 500 years ago. We collected 55 samples for soil characterization, fertility, and micromorphic analyses and compared these results to a noncultivated control soil previously sampled in an adjacent valley. Natural soil fertility levels for maize, cotton, and bean production were generally high during late prehispanic cultivation in the Pampa. Maintaining adequate nitrogren levels for production, however, would have required external inputs from livestock manure, guano, or leguminous plants. The management of low soil salinity levels was possible because of rapidly permeable soils and irrigation waters low in salt. Based on available water capacity and climate conditions, the Blaney‐Criddle Equation yields evapotranspiration rates indicating that irrigation frequency was necessary in a range of every 10–16 days during the growing season. © 2004 Wiley Periodicals, Inc.  相似文献   

16.
A visually prominent desert soil with a horizon of clay accumulation (Typic Natrargid) has formed under an arid climate in Panamint Valley, California, in sandy, very calcareous, saline fan alluvium in less than about 3500 yr, and probably less than 2000 yr. Such soils can be used as stratigraphic markers, but could be confused with other desert soils with clay-accumulation horizons (Haplargids) which occur much more commonly on desert alluvial fans, are mostly late Pleistocene or older, and do not form in parent materials that are still calcareous. This Natrargid formed in a playa-margin environment, where clay for translocation and sodium salts that engender rapid clay movement probably were provided by dust fall.  相似文献   

17.
Geoarchaeological investigations in western Middle Park provide important information for understanding the soil‐stratigraphic context of Paleoindian components, as well as the latest Quaternary environmental change and landscape evolution in a Southern Rocky Mountain intermontane basin. Paleoindian components are associated with the oldest two of four latest Quaternary stratigraphic units (1–4) recognized in co‐alluvial mantles (combined slopewash and colluvium) in uplands and in alluvial valley fills. Limited data suggest accumulation of unit 1 as early as ∼12,500 14C yr B.P. in alluvial valleys and by at least ∼11,000 14C yr B.P. in uplands was followed by brief stability and soil formation. A relatively widespread disconformity marks earliest Holocene erosion and substantial removal of latest Pleistocene deposits in upland and alluvial settings followed by unit 2 deposition ∼10,000–9000 14C yr B.P., perhaps signaling the abrupt onset of an intensified summer monsoon. In situ Paleoindian components in uplands are found in a moderately developed buried soil (the Kremmling soil) formed in units 1 and 2 in thin (≤1m) hillslope co‐alluvial mantles. The Kremmling soil reflects geomorphic stability in upland and alluvial settings ∼9000–4500 14C yr BP, and represents a buried landscape with the potential to contain additional Paleoindian components, although elsewhere in western Middle Park Early Archaic components are documented in morphologically similar soils. Kremmling soil morphology, the relative abundance of charcoal in unit 2 relative to younger units, and charcoal morphology indicate the expansion of forest cover, including Pinus, and grass cover during the early and middle Holocene, suggesting conditions moister than present. © 2010 Wiley Periodicals, Inc.  相似文献   

18.
The study of soil weathering processes College of Resources and Environment, rates and the associated influencing factors is crucial for understanding of the feedbacks between soil and environment, which will provide a basis for predicting soil behavior and evolution trend in the ecosystem under natural and anthropogenic forcings. This is also important for the effective management of soil resources. This article reviewed the methods for measuring soil weathering rates (including simulating leaching experiment, model calculation, isotope technique, element depletion and geochemical mass balance) and the influencing factors (including climate, organism, parent material, relief, time and human activities). In view of the serious degradation of soil resources, we proposed the challenge and opportunity of the research of soil weathering. The future study should focus on the critical processes, rates and the associated environmental thresholds of soil weathering under varying natural conditions and intensive human perturbations, including the establishment of the quantitative relationship between the weathering rates calculated by different methods, the analysis and interpretation of synergistic effects among multiple influencing factors, and the modeling and prediction of changing tendency of weathering rates under the impacts of both climatic changes and human activities, in order to guide the sustainable management of soil resource and mitigation of global change.  相似文献   

19.
孙德安  陈振新 《岩土力学》2012,33(Z2):16-021
目前大多数非饱和土的弹塑性本构模型用非饱和击实土的试验结果进行验证,但现场其他类型的土,如沉积土经常有在非饱和状态下外部环境变化的情况。现有的非饱和土弹塑性模型是否适用于沉积土一类的现场土是需要研究的课题。进行非饱和上海第③层土的吸力控制排水排气三轴剪切试验,使用文中提出的能统一考虑非饱和土水力性状和力学性状的弹塑性本构模型,预测上述三轴试验结果,并与试验数据进行比较。比较结果显示,建立的本构模型能够很好地预测非饱和上海软土的水力和力学性质,说明该模型不仅可以适用击实土的预测,还能够很好地适用于其他类型非饱和土的水力和力学性质的模拟。  相似文献   

20.
Toxicity of heavy metals adversely affects environment and human health. Organic materials derived from natural matters or wastes have been applied to soils to reduce the mobility of contaminants such as heavy metals. However, the application of cow bone powder (CB), biochar (BC), and eggshell powder (ES) is rarely investigated for the reduction of Pb bioavailability in soils irrigated with saline water. The objective of this study was to assess the effectiveness of CB, BC, and ES additions as immobilizing substances on Pb bioavailability in shooting range soil irrigated with deionized and saline water. Each additive of CB, BC, and ES at 5 % (w/w) was mixed with soils and then the deionized and saline water were irrigated for 21 days. With deionized water irrigation, the soils treated with CB, BC, and ES exhibited higher pH when compared with saline water irrigation. With saline water irrigation, the electrical conductivity, water-soluble anions, and cations were significantly increased in soils treated with CB, BC, and ES. The water-soluble Pb in soils treated with CB, BC, and ES was significantly decreased with saline water irrigation. On the other hand, the water-soluble Pb in soil treated with CB was increased with deionized water irrigation. Only BC with saline water irrigation decreased the Pb concentration in maize shoots.  相似文献   

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