贵州省修文县猕猴桃生态园区土壤重金属污染现状评价

[目的]探讨不同评价方法对贵州省修文县猕猴桃基地适用性,为猕猴桃栽培基地的选择和土壤健康风险研究提供科学依据。[方法]采用单因子污染指数和内梅罗综合污染指数对基地土壤重金属污染程度进行了分析,同时应用Hakanson潜在生态风险指数法和模糊数学法对基地土壤重金属潜在生态风险进行了评价。[结果]A基地中Cu,Ni,Hg分别超过国家土壤环境质量二级标准的1.03,1.14,2.3倍;B基地中Cu和Hg分别超过国家土壤环境质量二级标准1.03,2.0倍;C基地中Cu,Ni和Hg分别超过国家土壤环境质量二级标准1.18,1.01,1.77倍。用内梅罗综合指数法评价结果表明:A基地的土壤属于轻度污染级别,B基地和C基地属于尚清洁级别。3个基地的土壤重金属综合污染指数大小为:A基地(1.09)C基地(0.93)B基地(0.91);用潜在生态危害指数法评价结果则表明:A,B,C这3个基地的环境风险综合指数均小于150,表明8种重金属对环境的生态污染指数轻微。3个基地的土壤重金属环境风险综合污染指数大小为:A基地(83.61)C基地(78.89)B基地(75.46);用模糊数学法评价结果表明:A,B,C基地土壤均属于清洁范围,3个基地的评价分值大小为:B(97.16)C(95.44)A(94.31)。[结论]修文县猕猴桃3个基地的土壤重金属的污染特征大体相同,主要以Cu,Ni,Hg为主,但基地土壤受污染程度轻微,土壤状况良好。     

贵州省地道药材GAP基地土壤重金属含量及污染评价

对贵州省11个地道中药材GAP基地土壤中的5种重金属含量进行调查分析,分别以国家土壤环境质量二级标准和区域土壤重金属背景值作为标准对其单项和综合污染指数进行分析评价.结果表明:调查区域内各基地重金属含量水平差异很大,土壤重金属含量的变异系数6.6%～70.4%.调查区域内基地土壤受到了不同程度的污染,部分土壤达不到国家环境质量二级标准的要求.以国家土壤环境质量二级标准作为评价标准的评价结果为:单项污染指数最大2.5,综合污染指数最大1.9,受污染基地占27.3%.以区域土壤重金属背景值作为标准评价结果为:单项污染指数最大4.3,综合污染指数最大3.3,受污染基地占54.5%.在重金属污染因子中,Cd是主要污染因子,其次是Cu、Hg、As.     

遵义县农业土壤重金属镉分布特征及地质累积污染分析

采用地质累积指数法和污染程度指数法对贵州省遵义县农业土壤表层镉（Cd）污染现状进行调查和分析,结果表明,该县0～15cm表层土壤中Cd平均含量为0.356mg/kg。通过地球化学基线理论分析,该区域土壤中Cd的环境地球化学基线含量为0.147mg/kg;地质累积污染分析显示Cd的Igeo为0.691,该区域13.84%...     

云南省某锡矿废水污灌区土壤重金属污染评价分析

为揭示工矿企业污水灌溉对土壤环境质量的影响,以锡矿企业废水污灌区为例,对其表层土壤重金属Hg、As、Cd、Pb、Cr含量及pH值进行测定分析。对照国家《土壤环境质量标准》二级标准,采用标准对比法、单因子污染指数法和综合污染指数法,对污灌区土壤环境质量进行了评价。结果表明,研究区土壤pH值介于3.83～6.45之间,均值为5.14,土壤偏酸;Hg和Pb单因子污染指数全部样本为一级,土壤清洁且安全;Cr和Cd单因子污染指数分别有2.22%和4.44%的样本为二级,达到警戒级,说明土壤尚清洁,未受到污染;As单因子污染指数2.22%的样本为三级,Pi跃1,达轻污染级,为主要污染因子,表明土壤已受到As轻度污染;研究区综合污染指数值为1.16,达到轻度污染级。     

电镀废水污染区土壤重金属含量的测定及污染状况评价

运用原子吸收光谱法,测定了某地电镀废水污染区重金属污染土壤样品中Cd、Pb、Cu、Zn4种元素的含量,RSD小于1%,加标回收率在92.78%~103.2%之间,表明测定结果可靠。依据测定数据、国家土壤环境质量二级标准、内梅罗指数法及潜在生态危害指数法,对电镀废水污染区土壤重金属污染状况进行评价。按二级标准评价结果为中度以上污染;以内梅罗综合污染指数法进行评价,土壤受到重度污染;用潜在生态危害指数法对污染生态风险进行评估,总潜在生态风险程度为重度。因此应对该区污染土壤进行治理。     

某铅锌冶炼厂废弃地复垦整理区土壤重金属污染评价

对贵州省六盘水市某铅锌冶炼厂废弃地复垦整理区土壤中重金属Cu，Zn，Pb，Ni，Cd，Cr，Hg，As以及土壤部分理化性质进行了测定和分析，对土壤重金属污染状况进行了评价。结果表明：废弃地上堆放的铅锌冶炼矿渣中除Cu，Cr，Hg的含量较低、污染指数小于1之外，Zn，Pb，Ni，Cd，As的含量很高，其单项污染指数分别为2．95，45．14，1．00，10．67，50．41，综合污染指数高达36．98，属于剧烈污染源。项目区土壤综合污染指数在0．77～1．99之间；综合污染指数小于1的未受重金属污染的土壤占总样品数的50．00％，而综合污染指数〉1．00但没有超过2．00的样品数占总样品数的50．00％，说明项目区仅有部分土壤遭受重金属的轻度污染。采用适当的复垦整理、改良技术和合理的利用方式，可以促使该废弃地恢复农业生产能力。     

废弃铅锌矿区复耕后土壤-作物重金属污染特征及修复措施

[目的]了解废弃铅锌矿区复耕农田耕作层土壤—作物污染特征及变化情况,探究最合理的植物修复系统。[方法]利用基于GIS的Tominson负荷指数法对不同耕地重金属污染分布格局及来源进行分析;采用富集系数法(BCF),复合质量影响指数法(ⅡCQ)探究土壤—作物污染特征。[结果]研究区耕作层土壤中Cd,Zn,Pb,Hg含量分别是贵州省背景值的100,45,18,18倍,Cu,As,Cr与背景值基本相同;蒟蒻种植地为重度污染。茎块类作物食用部分富集重金属能力最强,稻米次之,瓜类作物最弱,当地瓜类作物可做为抗富集重金属的先行植物。[结论] Cd为主要控制因子,蒟蒻种植地为主要控制区域;根据研究区重金属空间分布特征,重度污染区域建议采用超富集植物修复及活化剂共同作用;中度污染区域种植抗富集蔬菜及阻绝污染源的方式;轻度污染区域稻米种植区采用钝化措施,从而达到修复耕作层土壤重金属目的。     

煤矿区周边农田土壤重金属积累特征及生态风险评价

为揭示开采活动对周边农田土壤重金属性质的影响,以贵州省织金县煤矿区废弃地周边农田土壤为研究对象,分别对距离矿区50 m、100 m、400 m的农田区A1、A2、A3表层土壤进行取样调查,分析了土样重金属含量及其分布特征,利用因子分析法对土壤重金属污染来源进行分析,分别采用内梅罗综合指数法、潜在生态危害指数法对其污染程度和生态风险进行评价。结果表明,农田区A1、A2、A3样点重金属含量均高于对照点,且距离矿区越近,农田土壤重金属积累越严重。因子分析结果表明,Cd、Cu、Ni、Zn主要来源于煤炭开采过程中的三废排放,Cr和Pb可能来源于成土母质,Hg、As可能来源于采矿产生的粉尘和当地煤炭燃烧产生的降尘。内梅罗综合指数评价结果表明,Hg、Cd、Cu、Cr是土壤重金属污染的主要因子,农田区A1、A2、A3的综合污染程度达到重污染水平的样点比例分别为66.7%、52.6%、6.2%;潜在生态危害指数评价结果表明,Cd、Hg是土壤重金属最主要的潜在生态风险因子,农田区A1、A2分别有50%、21.1%的样点处于强生态危害水平,内梅罗综合污染指数和潜在生态风险指数均表现为距离矿区越近,土壤重金属污染越严重,潜在生态风险越强。     

滇西陇川县耕地土壤环境质量分析评价

为揭示滇西地区土壤环境质量状况,以陇川县为例,参照《绿色食品产地环境技术条件》,对耕地土壤pH值、有机质、全氮、速效磷、速效钾营养元素含量及重金属元素铅、镉、汞、砷、铬、铜总量进行测定分析。采用标准对比法、单因子污染指数法和Nemero综合污染指数法,对其土壤环境质量进行了评价。结果表明,研究区土壤pH值介于3.49~7.45之间,均值为5.05,土壤偏酸;各营养元素平均值中有机质、全氮、速效磷含量为优良,速效钾含量为中等,有机质、全氮、速效磷、速效钾含量分别有64.17%、59.34%、75.33%、71.66%的耕地面积达到生产绿色食品土壤肥力要求,分别有35.83%、40.66%、24.67%、28.34%的面积土壤肥力不足;采用单因子污染指数法对土壤重金属评价,砷、铬、铜处于清洁状态;有20.27%、2.03%、4.73%的样本铅、镉、汞单因子污染指数大于1,所代表的面积受到铅、镉、汞轻度污染,镉有1.35%样本单因子污染指数大于2,所代表的面积受到镉中度污染;综合污染指数评价,4.79%样本达到轻度污染。     

北京市农业土壤重金属状态评价

以北京市土壤重金属背景值为标准,对比分析了农业土壤中Cr、Ni、Cu、Zn、As、Cd、Ph、Hg 8种重金属的含量及累积情况,并采用单因子污染指数法和综合污染指数法进行了土壤重金属污染评价。结果表明,北京市农业土壤存在着一定的Cr、Cu、Zn、As、Cd累积趋势,其含量的平均值分别为53．61、21．95、65．42、9．14、0．125mg·kg^-1,比相应的背景值高79．9％、17．4％、13．8％、28．9％、5．0％;Ni和Pb的累积则不明显,平均值比相应的背景值低7．9％、29．2％,分别为24．84和19．04mg·kg^-1;而Hg含量的平均值与背景值一致,为0．08mg·kg^-1。从单因子评价结果来说,Cr污染指数在1．06-2．93之间,所有的样点都处于轻度或中度污染状态;As、Cu、Zn、Cd的污染指数相对较小,平均值分别为1．29、1．17、1．13、1．05,有50％以上的样点处于轻度污染状态;而Ni、Ph、Hg的污染指数均小于1,有60％以上的样点处于清洁或尚清洁状态,污染较轻。若从综合评价结果来说,综合污染指数处于0．96～2．16之间,平均值为1．45,几乎所有的土壤样点都属于轻度污染状态。     

低山丘陵区不同坡位茶园土壤肥力特征研究

南方低山丘陵区是我国茶园的集中分布区域, 研究其土壤肥力状况是改善茶园土壤养分状况、实现茶叶安全高效生产和可持续发展的基础.选择川西茶区典型低山丘陵茶园, 通过野外调查与样带采样研究土壤养分性质, 利用主成分分析等多元统计方法定量化比较了不同坡位及对照间土壤肥力质量.结果表明: (1)茶园土壤中砂粒含量最高, 平均占总量的39.13%, 其次是黏粒, 粉粒含量居第3位;土壤pH低于4.5, 有机质和全氮含量较低, 速效氮含量较高, 速效磷缺乏, 速效钾变化不显著.与林地、撂荒地相比, 茶园土壤各粒级含量变化规律不明显.有机质和全氮除在下坡位略高于撂荒地外, 其他坡位均小于撂荒地和林地;速效养分变化规律不显著.(2)茶园土壤肥力沿坡面变化明显, 以上坡位为基准, 土壤肥力指数PI值为零, 中坡位PI值(-13.64%)低于上坡位PI值(0)和下坡位PI值(14.39%).(3)与撂荒地、林地相比, 茶园的土壤肥力综合指数QI值最低.茶园、撂荒地、林地的QI值分别为0.56、1.11和2.73.     

The effect of tea plantation age on soil water-stable aggregates and aggregate-associated carbohydrate in southwestern China

Soil carbohydrates constitute an important component of soil organic matter (SOM), and substantially contribute to the stabilization of soil aggregates. Here, we aimed to investigate the distribution of water-stable aggregates and carbohydrates within water-stable aggregates of soil in tea plantations located in Zhongfeng Township of Mingshan County, Sichuan, which is in southwest China. Samples were collected from tea plantations of different ages (18, 25, 33, and 55 years old) and an area of abandoned land was used as a control(CK). We also examined correlations between soil carbohydrates fractions and aggregate stability. The results showed that the mean weight diameter (MWD) of soil aggregates in the tea plantations was significantly higher than that the control. Furthermore, the soil aggregate stability was significantly enhanced in tea plantations, with the 25-year-old plantation showing the most pronounced effect. Soils in the plantations were also characterized by higher concentrated acid-extracted carbohydrate content, and carbohydrate content in both surface and sub-surface layers were higher in the 25-year-old plantation. We also detected a significant positive correlation between the carbohydrate content of soil and MWD after tea plantation (P < 0.01). Notably, the association between dilute-acid extracted carbohydrate and the aggregate stability showed the highest correlation, indicating this carbohydrate fraction could be used as an index to reflect changes in soil quality during tea plantation development. We should develop a potential fertilisation programme to maintain SOM- Carbohydrates within aggregates and the appropriate pH for preventing soil structure degradation after 25 years of tea planting.     

茶园管理方式对土壤微生物群落影响的研究进展

茶叶生产中往往出现种植茶树品种或植物种类单一、不合理灌溉以及过度施用化肥和除草剂等问题,从而影响茶叶的产量特别是品质。探讨不同管理方式对茶园土壤微生物群落的影响,将为茶叶提质增产提供科学依据。本文对国内外相关研究进行了归纳与总结,综述了种植模式、灌溉措施、施肥方式和杂草防控四种不同管理措施对茶园土壤微生物群落的影响以及微生物群落与土壤理化性质的相互关系,分析了土壤微生物群落在改善茶园土壤肥力中的作用。科学的茶园管理方式能够改变微生物群落的组成和结构,改良茶园土壤肥力,促进茶树的生长发育,对提高茶叶产量和品质具有重要的意义。未来应加强对茶园土壤生态学的研究,为茶园的科学管理和可持续发展提供理论依据。     

基于SWAT模型茶园化肥减施增效配比研究

茶园化肥减施技术是改善茶园土壤环境、降低茶区地表水体富营养化的主要措施之一,有助于茶园生态环境的改善。利用云南省西双版纳自治州勐海县勐邦库区曼真村2018年3—9月大田试验数据及勐海县勐邦库区2011—2016年气象水文资料,基于SWAT模型建立区域尺度茶园化肥减施模型,构建环境效益评价体系(土壤肥力指标、水环境指标和经济效益指标),采用模糊综合评价法定量计算茶园不同施肥方式(常规化肥、70%化肥+有机肥配施、70%化肥+缓释肥配施、70%化肥+土壤改良剂配施)的环境综合效益指数,系统研究勐海茶园化肥减施增效配比方案。结果表明:1)勐邦库区流域月尺度径流与水质的模拟和实测结果趋势相同,决定系数R2=0.895,纳什系数Ens=0.837,模型拟合度高;2)综合效益权重计算结果表明,水环境指标(0.412)土壤肥力指标(0.317)经济效益指标(0.271),水环境对综合效益存在显著影响;3)勐海茶园最优的化肥减施配比方案为70%化肥+缓释肥配施,其土壤肥力效益指数为0.96,水环境效益指数为0.97,经济效益指数为0.99,综合效益评价指数为0.97。综上, 70%化肥+缓释肥配施能有效降低茶园地表水体富营养化产生的风险,同时能够提高茶园土壤肥力而不影响茶园的经济效益。因此,配施缓释肥是现阶段较为适合勐海茶园的环境友好型施肥技术。     

茶园土壤微生物总DNA不同提取方法的比较

传统的微生物分离培养方法,在反映茶园土壤微生物基因信息上有很大的局限性,因此,目前逐步被分子生态学的方法替代,而获得高质量、大片段、无偏好的土壤微生物总DNA则是茶园土壤微生物分子生态学研究的基础。本文采用SDS高盐法、变性剂加SDS高盐法、脱腐SDS高盐法、CTAB法和Krsek改进法5种土壤微生物DNA提取方法分别从茶园土壤微生物中提取总DNA,并对5种方法提取的DNA的片段大小、质量和产量进行了综合评价。结果表明,Krsek改进法提取到的DNA片段最大（〉23kb）、纯度最高（OD2UOD280〉1．70;OD2UOD230〉1．35）、产量较高（〉34．50μg／gdrysoil）且不需纯化就可以用于PCR扩增和RFLP分析。因此,Krsek改进法是一种高效、可靠且适合于茶园土壤微生物分子生态学研究的DNA提取方法。     

Soil and phosphorus redistribution along a steep tea plantation in the Feitsui reservoir catchment of northern Taiwan

Feitsui reservoir, the major water supply of Taipei city, has shown declining water quality in recent years. The reservoir is located in an area famous for tea cultivation, and the question arises as to whether the hillside tea plantations have contributed to increased sediment and nutrient discharge into the reservoir. In this study, soil and phosphorus redistribution were examined along a steep tea plantation in the reservoir's catchment and the provenance of reservoir sediment was assessed. Fallout radionuclides were used as soil erosion/deposition tracers and as markers of sediment sources. Continuous fertilizer application has raised (inorganic) phosphorus levels in the studied tea plantation. The plantation's narrow bench terraces trap eroded material and slow down soil and nutrient translocation. Nevertheless, eroded soil and phosphorus have accumulated on a vegetated toeslope below the tea plantation. The reservoir sediment contained significant amounts of inorganic phosphorus and cesium-137, and application of a mixing model resulted in a surface soil contribution of approximately 30%. This points towards tea plantations as possible sediment and pollutant sources and underlines the necessity of soil conservation strategies, such as the maintenance of vegetated riparian buffer zones. However, other sources, such as landslide debris and urban wastewaters, cannot be entirely ruled out. Further research is needed to better characterize the catchment's soils and sediments and to improve sediment fingerprinting efforts. Potential point and non-point pollution sources need to be examined in detail to better understand how phosphorus enters the reservoir.     

福建省安溪县铁观音茶园土壤氮素状况

为了解福建省安溪县铁观音茶园土壤氮素供应能力,对安溪县77个铁观音茶园土壤(分0～20、20～40 cm两个土层)全氮、碱解氮含量及对应的铁观音茶叶氮含量进行了测试分析。结果表明:安溪县铁观音茶园0～20 cm土层土壤全氮含量属中上水平,平均值1.13 g/kg,Ⅱ级(尚可)及以上样点比例达90.9%;20～40 cm土层土壤全氮含量属中下水平,平均值0.81 g/kg,Ⅱ级(尚可)及以下样点比例占77.9%。黄壤、红壤、水稻土改植、赤红壤茶园土壤全氮含量较高,粗骨土、潮砂土茶园土壤全氮含量较低;土壤全氮与有机质含量呈显著的正相关关系。安溪县铁观音茶园土壤碱解氮总体含量较为丰富,0～20cm土层土壤碱解氮含量平均值105.42 mg/kg,Ⅱ级(尚可)及以上样点比例达到97.4%;20～40 cm土层平均值75.02 mg/kg,Ⅱ级(尚可)以上样点比例占84.4%。黄壤、红壤、赤红壤、水稻土改植茶园土壤碱解氮含量较高,粗骨土、潮砂土茶园土壤碱解氮含量较低;土壤碱解氮与全氮、有机质含量呈显著的正相关关系。供试铁观音茶叶氮含量与土壤全氮、碱解氮含量相关关系不显著,土壤碱解氮含量能否作为铁观音茶园土壤供氮能力的指标,以及在铁观音茶树的营养诊断时采摘鲜叶的氮素含量是否能作为茶树氮素缺素的诊断指标有待进一步研究。安溪县铁观音茶园土壤氮素管理时应注重氮肥深施,同时增施有机肥、降低速效氮肥的施用比例。     

Soil and phosphorus redistribution along a steep tea plantation in the Feitsui reservoir catchment of northern Taiwan

Abstract

Feitsui reservoir, the major water supply of Taipei city, has shown declining water quality in recent years. The reservoir is located in an area famous for tea cultivation, and the question arises as to whether the hillside tea plantations have contributed to increased sediment and nutrient discharge into the reservoir. In this study, soil and phosphorus redistribution were examined along a steep tea plantation in the reservoir's catchment and the provenance of reservoir sediment was assessed. Fallout radionuclides were used as soil erosion/deposition tracers and as markers of sediment sources. Continuous fertilizer application has raised (inorganic) phosphorus levels in the studied tea plantation. The plantation's narrow bench terraces trap eroded material and slow down soil and nutrient translocation. Nevertheless, eroded soil and phosphorus have accumulated on a vegetated toeslope below the tea plantation. The reservoir sediment contained significant amounts of inorganic phosphorus and cesium-137, and application of a mixing model resulted in a surface soil contribution of approximately 30%. This points towards tea plantations as possible sediment and pollutant sources and underlines the necessity of soil conservation strategies, such as the maintenance of vegetated riparian buffer zones. However, other sources, such as landslide debris and urban wastewaters, cannot be entirely ruled out. Further research is needed to better characterize the catchment's soils and sediments and to improve sediment fingerprinting efforts. Potential point and non-point pollution sources need to be examined in detail to better understand how phosphorus enters the reservoir.     

Effects of organic and other management practices on soil nematode communities in tea plantation: a case study in southern China

Four major tea management practices (organic, pollution‐free, conventional, and semi‐natural) are employed in Chinese tea plantations at present. These practices can induce changes in the physiochemical parameters, microorganism community and enzyme activity in tea plantation soil. However, understanding of their effects on soil nematodes is still scarce. This study aimed to investigate whether and how different management practices affect the biodiversity, function, and structure of soil nematode communities in tea plantation habitats. The soil nematode community structures and ecological indices were determined from the soil samples collected more than 6 y after their respective farming practices were first applied, and different management practices did not greatly affect soil nematode community evenness or species diversity, but organic practice increased nematode trophic diversity, common species diversity, and species richness. Pollution‐free practice considerably increased fungivorous nematodes, and both pollution‐free and conventional practice decreased bacterivorous nematodes markedly in the subsurface layers of soil. Predator and omnivorous nematodes were found to be more abundant in semi‐natural plantation. Organic practice was more sustainable and suitable for tea cultivation, with the greatest biodiversity, best nutrient conditions, higher and more stable C/N ratio and lower interference in the food web.     

湖南丘陵茶区绿茶生产优劣势及主要生态调控技术研究

湖南丘陵区具有茶叶知名品牌多,茶叶生产成本低、产量高等优势,丘陵区茶园在湖南省茶叶生产中占有山区茶园无可比拟的重要地位。但丘陵茶园存在土壤贫瘠、季节性干旱严重、生态组分简单等生态问题,造成茶叶品质下降,并影响茶叶的生产效益。小区试验表明:在丘陵茶园开展稻草覆盖可有效改善土壤肥力,显著提高茶树生长季节(3~10月)表层土壤的水分含量;夏秋高温季节进行遮阳网覆盖遮荫,可改善茶园光照、温度和水分条件,有利于新梢中氨基酸和叶绿素等内含物的积累,提高名优茶的产量;建立人工复合生态茶园和遮阳网覆盖遮荫同样有改善丘陵茶园生态环境的效果,还可增加天敌数量,抑制茶园主要害虫的发生和发展。建议在湖南丘陵茶区推广复合生态茶园技术,在茶树行间种植落叶乔木,全园覆盖稻草。