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1.
何帅  尹飞虎  谢海霞 《干旱区地理》2017,40(5):1061-1069
选择新疆准噶尔盆地灰漠土作为研究对象,通过测定灰漠土中不同形态的无机磷素含量并进行土壤磷素等温吸附实验,研究灰漠土中各形态无机磷素的有效性和土壤磷吸附特征。结果表明,灰漠土中无机磷形态主要是Ca-P,占全磷含量75%以上,且以Ca10-P形式为主,其次为Ca8-P和Ca2-P,无机磷中Al-P、Fe-P和O-P含量较少。全剖面中随着土层深度增加,Ca2-P、Ca8-P和Al-P占全磷总量的比例减少,Ca10-P占全磷总量则有所增加,0~20 cm土层全磷和Olsen-P含量最高,分别平均为926 mg·kg-1和51.54 mg·kg-1。统计分析表明Ca2-P、Al-P是最有效的磷源,Ca8-P和Fe-P是第二有效磷源,O-P和Ca10-P则是作物的潜在磷源。利用Langmuir方程拟合灰漠土的磷等温吸附曲线,得出土壤最大吸磷量(Xm)为957±629 mg·kg-1,吸附参数(K)为149.285±89.225;灰漠土的粘粒含量对Xm影响最大,其次是有机质,pH值影响最小。  相似文献   

2.
长江中下游浅水湖泊表层沉积物潜在可交换性磷研究   总被引:7,自引:0,他引:7  
利用无限稀释外推法 (IDE法 )和Hieltjes与Lijklema提出的H-L法对长江中下游浅水湖泊表层沉积物中可交换性磷进行测定,研究了IDE法测定的潜在可交换性磷 (IDE-P )与H-L法使用NH4Cl测定的氯化铵磷 (NH4Cl-P )在不同污染程度沉积物中的分布规律及二者关系,并对IDE-P和NH4Cl-P与沉积物土壤测试磷 (STP)、磷吸附饱和度 (DPS)、总磷 (TP)和有机质关系进行讨论。结果表明,沉积物IDE-P和NH4Cl-P分布遵循重污染沉积物>污染较轻沉积物的规律,IDE-P含量高于NH4Cl-P含量;不同沉积物的(NH4Cl-P/IDE-P)%变化较大;IDE-P和NH4Cl-P与STP、DPS、总磷和有机质的相关性较好。  相似文献   

3.
利用2016年在克拉玛依酸雨观测站采集的降水样品,分析了降水中主要阴阳离子(F^-、Cl^-、NO^-3、SO^2-4、Na^+、NH^+4、K^+、Mg^2+、Ca^2+)、重金属元素(Al、Mn、Fe、Ni、Cu、Zn、Cd、Pb、Hg)、总碳总氮浓度特征及可能的来源。结果表明:该区降水pH值在5.1~6.88之间,雨量加权平均值为6.25,其中pH>5.6的样品占94%。降水中各离子雨量加权浓度的大小顺序为Ca^2+>NH^+4>SO^2-4>NO^-3>Cl^->Mg^2+>Na^+>K^+>F^-,表现出了内陆性大气降水的特征,其中Ca^2+是最主要的阳离子,年均值为182.09μeq·L^-1,SO^2-4是最主要的阴离子,年均值为87.28μeq·L^-1,表明硫酸盐是该地区降水中的主要致酸物质。降水中总离子浓度秋季最高,春夏次之,冬季最低,其中SO^2-4、NO^-3、NH^+4、Ca^2+、Na^+浓度变化明显。相对酸度(FA)和中和因子(NF)计算结果表明99.5%的降水酸度被碱性成分中和,其中Ca^2+的中和能力最强,其次是NH^+4。降水中重金属元素Zn的均值最大,其次是Fe,最小的是Pb,与国内外城市比较,克拉玛依大气降水中大部分重金属含量都不高,其降水中有毒重金属污染较轻。可溶性总碳(DTC)、可溶性有机碳(DOC)和可溶性无机碳(DIC)浓度变化范围大,分别为1.62~9.97 mg·L^-1、1.62~7.19 mg·L^-1和0~3.75 mg·L^-1,平均浓度分别为4.37 mg·L^-1、3.60 mg·L^-1和0.78 mg·L^-1,可溶性总氮(DTN)的浓度变化范围为0.64~8.01mg·L^-1,年均含量为2.69 mg·L^-1,都与降水量呈负相关关系,而DOC和DTN的湿沉降通量与降水量呈明显的正相关关系。基于相关性分析表明,SO^2-4和NO^-3主要来自燃煤和化石燃料燃烧,Na^+、Mg^2+和Ca^2+主要来自风沙、扬尘,大气中铵类化合物主要以铵的硝酸盐形式存在。各重金属元素之间相关性差异较大,重金属主要污染源为金属冶炼、燃煤及人为活动。克拉玛依大气降水的化学组成特征主要受人为活动、化工生产、燃煤以及沙尘活动等影响。  相似文献   

4.
为探讨干旱区作物灌溉对盐碱土无机碳传输的影响,通过选择不同含盐量的土壤,即耕地土(F)、混合土(C)和原生荒漠土(D),分别种植水稻(R)和棉花(C),进行了一个生长季的淋溶实验,并定期收取且分析土壤淋溶液中的可溶性无机碳(DIC)含量。结果表明:(1)水稻处理无机碳的淋溶主要集中在秧苗分蘖期和幼穗发育期,而棉花处理则集中在花铃期和吐絮期;(2)不同含盐量土壤在同一灌溉量下,土壤含盐量越高,其淋溶过程得到的无机碳总量越大,最高约为8.4 g·m-2·a-1,最低仅约0.7 g·m-2·a-1;(3)同种土壤不同灌溉量,其水稻高于棉花,高出值范围为2.9~4.1 g·m-2·a-1;种植作物处理得到的无机碳总量均大于其相应对照处理的量(p<0.05)。研究结果表明,土壤的盐含量及作物灌溉量对土壤无机碳淋溶有重要影响。  相似文献   

5.
汉江上游黄土常量元素地球化学特征及区域对比   总被引:6,自引:0,他引:6  
本文对汉江上游黄土的常量元素含量及相关地球化学参数CIA、Na/K、淋溶系数、退碱系数、残积系数等进行了系统分析。结果显示:① 汉江黄土的主要化学成分为SiO2、Al2O3和Fe2O3,三者含量总和达767.3 g/kg;常量元素含量大小排序为SiO2>Al2O3>Fe2O3>K2O>MgO>Na2O>CaO。风化成壤过程中Na、Ca、Mg、Si发生不同程度的迁移淋溶,而Fe、Al、K相对富集。② 其风化成壤强度呈现从马兰黄土L1→过渡性黄土Lt→古土壤S0逐渐升高、全新世黄土L0又降低的规律,记录了该区域气候经历了末次冰期(55.0-15.0 ka BP)冷干、早全新世(15.0-8.5 ka BP)增温增湿、中全新世(8.5-3.1 ka BP)达到最暖湿,晚全新世(3.1-0.0 ka BP)降温变干的演变过程。③ 汉江黄土与洛川、巫山、下蜀黄土的元素组合特征高度一致,不同地区常量元素(CaO除外)含量十分接近且UCC标准化值变幅均小于0.25,这暗示了它们风化之初具有相似的风成沉积基础;但不同区域黄土的化学风化强度差异明显,大致呈现洛川黄土<汉江黄土<巫山黄土<下蜀黄土的趋势,与中国现代季风气候的空间变化规律相吻合,即不同地区黄土风化程度差异主要是东亚季风变化影响的结果。  相似文献   

6.
松嫩平原西部盐沼湿地水环境化学特征   总被引:9,自引:1,他引:9  
邓伟  何岩  宋新山  阎百兴 《地理研究》2000,19(2):113-119
松嫩平原西部盐沼湿地水环境碱化程度高,水中的pH值普遍高于8.0,多数为苏打钠型水。在对本区盐沼基本水环境化学特征阐述的基础上,通过对水化学的基本变量CO32-、HCO32-、Cl-、Ca2+、Mg2+、SO42-、Na+和派生变量(Cl-+SO42-)/HCO32-及Na+/(Ca2+ Mg2+)等的相关分析,得出各水化学变量之间的相关关系,并以pH值为分类基础得到了判别函数和判别区域图,对区域盐沼湿地水环境化学特征的研究方法作出了有意义的尝试。  相似文献   

7.
This study investigated the effects of sawdust as a soil amendment on certain growth parameters of Solanum esculentum Linn. grown in soil polluted with various concentrations of waste engine oil, and changes in the physicochemical properties of the soil. The purpose was to assess the soil remediation potentials of sawdust in waste engine oil-polluted soil. The experiment was divided into three regimes: control(air-dried soil without waste engine oil and with clean sawdust), polluted(waste engine oil-contaminated soil), and amended(oil-polluted soil amended with sawdust). Enough 3-kg soil samples were sieved and air-dried to prepare five treatment levels of waste engine oil-contaminated soil(30 m L, 1%; 60 m L, 2%; 90 m L, 3%; 120 m L, 4%; and 150 m L, 5%), as well as five additional treatment levels(the same amounts of oil contamination) in soil amended with sawdust. The treatment levels were replicated five times in a completely randomized design. A nursery bed was planted with a hybrid tomato variety(Roma V F) obtained from National Horticultural Research Institute(NIHORT) in Ibadan, Nigeria. During the maturation period, the growth parameters such as plant height, number of leaves, and number of branches per plant were determined and then the harvested plants were oven dried at 70 °C for 48 hours to determine their dry weights. The effects of the sawdust amendment on the soil were assessed by determining the soil p H(glass electrode p H meter), total nitrogen(Kjeldahl method), total phosphorus(Bray-1 solution), and potassium(on the leacheate by a flame photometer). Chromium, lead, and cadmium contents were determined using an atomic absorption spectrophotometer. Analysis of variance and a Duncan multiple-range test were employed to test significant differences in the soil properties of the three regimes. The growth performance of Solanum esculentum Linn. in the amended regime(soil with sawdust) at the 150-m L waste engine oil-contamination level was significantly higher than in the polluted regime(soil without sawdust). After plant harvest, the p H of the soil was shown to be clearly affected by the addition of waste engine oil. The control soil(air-dried only, no sawdust, no oil) had the highest p H value, 6.60, which was significantly different from the p H values at other levels of waste engine oil contamination. However, when amended with sawdust, the control soil had a significantly lower p H value than the unamended control soil. This study further demonstrates that sawdust has the potential of amending waste engine oil-contaminated soil for increasing tomato growth performance because it is capable of increasing the soil nutrient content and reducing the soil total hydrocarbon content.  相似文献   

8.
选取无人为干扰区、人为干扰区共55个土壤样品测定全氮磷钾含量,结合实测光谱的微分变换建立预测模型,并筛选出不同人为干扰下最优模型。结果表明:人类活动造成土壤全氮磷钾含量降低,数据集中程度和分布状态均发生变化。无人为干扰区以二阶微分建立的全氮、全钾含量预测模型和全磷以对数的倒数一阶微分建立的模型建模集r^2均超过0.9,检验集相对分析误差(RPD)均大于2.0,预测效果最佳。人为干扰区以倒数一阶微分建立的全氮、全磷含量预测模型不仅RPD>2.0,而且r^2> 0.92,也达到极好水平。入选RPD> 2预测模型的敏感波段中,无人为干扰区均位于可见光近红外波段,而人为干扰区则在近红外波段。这为今后提高全氮磷钾含量预测精度提供了新视角。  相似文献   

9.
The northern Great Plains of Canada stretch from the Precambrian Shield near Winnipeg, Manitoba, westward for ∼1,700 km to the Rocky Mountains foothills. This vast region of flat to gently rolling terrain contains a very large number of salt lakes. Major ion chemical data on ∼500 of them are available. Although the average brine (salinity, 37 ppt) is a Na+−SO4 2− type of water, the lakes exhibit a wide range of salinities and ionic compositions. This diversity is confirmed by Q-mode cluster analysis; it identified thirteen major water chemistry types. Most ions display distinct trends, both spatially and with increasing salinity. All dissolved components increase with increasing salinity, but at different rates. The relative proportions of Ca2+ and HCO3 +CO3 2− ions show a strong decrease with increasing brine salinity, whereas SO4 2− ions increase with increasing salinity. The ionic proportions of Na+, Mg2+, K+ and Cl exhibit no significant relationship with salinity. R-mode factor analysis of the lake water chemistry, combined with selected environmental parameters, identifies groundwater composition, climate, and the elevation of the lake within the drainage system as most important in controlling brine chemistry and salinity on a regional basis. Variability in source of ions, reaction processes and products are undoubtedly key factors in helping to explain brine chemistry of an individual basin or variation from a local perspective, but these factors are generally poorly understood and not quantified on a regional basis. Palliser Triangle Global Change Project Contribution Number 3.  相似文献   

10.
In order to assess and improve the engineering stability of saline soil with high chloride content along a 40-km section of the Chaerhan-Golmud Highway in northwestern China, more than 200 monitoring p...  相似文献   

11.
镇江下蜀土剖面的化学风化强度与元素迁移特征   总被引:5,自引:1,他引:5  
The chemical weathering intensity and element migration features of the Xiashu loess profile in Zhenjiang are studied in this paper.(1)The Xiashu loess profile underwent moderate chemical weathering.It seems that the precipitation is a more important factor than the temperature in controlling the process of the chemical weathering.(2)The major elements such as Si,K,Na,Ca,Mg,Mn and P were migrated and leached,while the elements Fe and Ti were slightly enriched.The migration features of the major elements reveal that the Xiashu loess finished the primary process of chemical weathering characterized by leaching of Ca and Na,and almost reached the secondary process characterized by leaching of K.Except the elements Sr and Ga,other trace elements such as Th,Ba,Cu,Zn,Co,Ni,Cr and V were enriched.It might be caused by both the biogeochemical process and the adsorption of trace elements by clay mineral and organic materials.(3)The difference of element migration down the Xiashu loess profile reveals that the climate was warm and wet at the early-middle stage of the middle Pleistocene.At the end of the middle Pleistocene,it became dry and cool.At the early stage of the Late Pleistocene,the paleoclimate became warm and wet again.As a whole,the paleoclimate generally became drier and cooler in this region from the beginning of the middle Pleistocene.  相似文献   

12.
The chemical weathering intensity and element migration features of the Xiashu loess profile in Zhenjiang are studied in this paper. (1) The Xiashu loess profile underwent moderate chemical weathering. It seems that the precipitation is a more important factor than the temperature in controlling the process of the chemical weathering. (2) The major elements such as Si, K, Na, Ca, Mg, Mn and P were migrated and leached, while the elements Fe and Ti were slightly enriched. The migration features of the major elements reveal that the Xiashu loess finished the primary process of chemical weathering characterized by leaching of Ca and Na, and almost reached the secondary process characterized by leaching of K. Except the elements Sr and Ga, other trace elements such as Th, Ba, Cu, Zn, Co, Ni, Cr and V were enriched. It might be caused by both the biogeochemical process and the adsorption of trace elements by clay mineral and organic materials. (3) The difference of element migration down the Xiashu loess profile reveals that the climate was warm and wet at the early-middle stage of the middle Pleistocene. At the end of the middle Pleistocene, it became dry and cool. At the early stage of the Late Pleistocene, the paleoclimate became warm and wet again. As a whole, the paleoclimate generally became drier and cooler in this region from the beginning of the middle Pleistocene.  相似文献   

13.
通过对甘肃省金昌市(镍矿城市)建成区的土壤重金属调查研究,揭示了其重金属来源、污染现状及其环境风险。结果表明:当地主要矿产品Ni和Cu两种重金属的土壤污染最严重,与《土壤环境质量标准》(GB15618-1995)的III级标准比较,样品Ni和Cu的超标率分别为70%和57%,污染面积分别为26 km2和24 km2;土壤As和Cd污染主要集中在矿冶区和尾砂库附近,居民区土壤污染程度低;土壤Cr污染出现在尾砂库和采矿区附近,污染面积为3 km2。在城区土壤中,Co、Cu、Cd、Pb与Zn的污染来源及空间分布具有相似特征,而土壤As污染与Ni污染特征相近。Nemero综合指数评价结果表明,高风险区域主要分布在东部矿冶区、北部尾砂库和西南角采矿区,城市居民区的土壤重金属污染水平较低。  相似文献   

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通过人工制冷的方法收集2013 年华南师范大学石牌校区大气冷凝水52 个样品,对其进行pH 值和阴阳离子分析。结果表明:2013 年春季石牌校区绝大多数冷凝水样品的pH 值分布范围为5.00~6.47,平均值为5.97,已不属于酸雨。冷凝水的阴阳离子总质量浓度(TDS)介于57.87~484.38 μeq/L 之间,平均值为154.53 μeq/L;各离子质量浓度高低依次为2-4 SO >Ca2+> -3 NO >Na+>Cl->NO2->Mg2+≈K+>F-。石牌校区冷凝水的这种离子质量浓度分布特征显示:其清洁程度较优于2011 年春季该校区和同期上海大气冷凝水,而较差于云南丽江的大气降水,与广东鹤山和青海瓦里关山等地的大气降水相当。其污染来源除部分属自然源外,还主要与建筑活动、工业生产、汽车尾气等人类活动等有密切关系。  相似文献   

17.
该文通过太行山几种土壤类型模拟降雨实验,研究其自然状态的土壤总氮、可溶态氮、总磷、可溶态磷的流失量及流失浓度。研究表明,自然状态土壤氮、磷流失初始浓度最高,随后呈缓慢降低趋势;总氮、总磷及可溶态磷浓度与土壤中氮磷含量有一定相关性,但受其它因素影响也较大;可溶态氮浓度与土壤中氮含量关系不大;各土壤累积产流量大小与土壤渗水性、表层结构及地表植被覆盖有很大关系,总氮、总磷累积流失量大小依次是棕壤土>石灰性褐土>褐土>淋溶褐土>酸性粗骨土。  相似文献   

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石家庄市地表水源氮、磷污染分布特征   总被引:4,自引:0,他引:4  
氮、磷物质的输入是造成地表水源富营养化的主要原因,研究氮、磷污染分布特征对于了解其来源及其流失规律具有重要意义。笔者对石家庄市地表水源现状及环境背景水质进行了调查和分析,结果表明:岗南水库氮、磷污染丰水期比枯水期重;氮、磷元素形态及其流失形式均表现为非点源污染特征;汛期洪水输入是岗南水库氮、磷污染物的主要来源方式。  相似文献   

20.
新疆表土磁学性质及其环境意义   总被引:1,自引:1,他引:1  
在新疆地区采集了331块表土样品,分析了样品的磁性特征(磁性矿物种类、磁性矿物含量和粒径组成)及其环境意义。结果指示新疆地区表土磁性特征存在较大的区域差异。北疆样品中磁性矿物总体含量较高,以单畴和假单畴颗粒的磁铁矿、磁赤铁矿等软磁性矿物为主,南疆样品中磁性矿物含量较低,硬磁质含量稍高,单畴颗粒矿物所占比重较北疆低;伊犁地区样品的磁性矿物在组成上与南疆样品更为接近,但成壤相对较强,超顺磁颗粒含量高。新疆地区表土磁性特征差异在一定程度上反映了新疆地区环境因子的区域差异,尤其是年均降水的不同。  相似文献   

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