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Soil Erodibility and Physicochemical Properties of Collapsing Gully Alluvial Fans in Southern China
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作者 DENG Yusong SHEN Xue +3 位作者 XIA Dong CAI Chongfa DING Shuwen WANG Tianwei 《土壤圈:英文版》 SCIE CAS CSCD 2019年第1期102-113,共12页
In southern China, collapsing gully erosion produces massive deposits of sediment on the plough layer of alluvial fan farmland,leading to reduced nutrients, increased erodibility, and even desertification. The aim of ... In southern China, collapsing gully erosion produces massive deposits of sediment on the plough layer of alluvial fan farmland,leading to reduced nutrients, increased erodibility, and even desertification. The aim of this study was to investigate soil erodibility(the factor K in the Universal Soil Loss Equation, USLE) and physicochemical properties of the alluvial fans of the most severe collapsing gully erosion areas(Hubei, Jiangxi, Fujian, and Guangdong provinces) in southern China. The soils of the collapsing gully alluvial fans had a higher bulk density, but a lower total porosity, saturated water content, and silt and clay fractions than the control(CK) soils from the farmland without desertification. Soil quality gradually decreased from fan edge to fanhead. Significant decreases were found in soil p H, organic matter, cation exchange capacity, and total potassium, nitrogen, and phosphorus, as well as available nitrogen, phosphorus, and potassium, resulting in a gradual decrease in soil nutrients from the fanedge to the fanhead. Soil erodibility was greatest in the fanhead, and soil erodibility K values of the alluvial fans were 53.71%, 66.28%, 67.53%, and 71.68% greater than that in those of the CK soils of Hubei, Jiangxi, Fujian, and Guangdong, respectively, indicating a significant correlation between the soil erodibility K values and physicochemical properties, particularly sand fraction and organic matter content. The results provide new insights into the relationship between soil physicochemical properties and erodibility of alluvial fans, and suggest that improving soil structure might increase soil fertility in the collapsing gully alluvial fan farmland. 展开更多
关键词 SOIL erosion SOIL FERTILITY SOIL property SOIL quality SOIL structure
Changes in soil microbial community response to precipitation events in a semi-arid steppe of the Xilin River Basin, China
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作者 ZHANG Hui LIU Wenjun +5 位作者 KANG Xiaoming CUI Xiaoyong WANG Yanfen ZHAO Haitao QIAN Xiaoqing HAO Yanbin 《干旱区科学:英文版》 SCIE CSCD 2019年第1期97-110,共14页
In the context of climate change, precipitation is predicted to become more intense at the global scale. Such change may alter soil microbial communities and the microbially mediated carbon and nitrogen dynamics. In t... In the context of climate change, precipitation is predicted to become more intense at the global scale. Such change may alter soil microbial communities and the microbially mediated carbon and nitrogen dynamics. In this study, we experimentally repackaged precipitation patterns during the growing season(from June to September) of 2012 in a semi-arid temperate steppe of the Xilin River Basin in Inner Mongolia of China, based on the 60-year growing season precipitation data. Specifically, a total amount of 240 mm simulated precipitation was assigned to experimental plots by taking the following treatments:(1) P6(6 extreme precipitation events, near the 1st percentile);(2) P10(10 extreme precipitation events, near the 5th percentile);(3) P16(16 moderate precipitation events, near the 50th percentile);and(4) P24(24 events, 60-year average precipitation, near the 50th percentile). At the end of the growing season, we analyzed soil microbial community structure and biomass, bacterial abundance, fungal abundance and bacterial composition, by using phospholipid fatty acid(PLFA), real-time quantitative polymerase chain reaction(RT-qPCR) and 16S rRNA gene clone library methods. The extreme precipitation events did not change soil microbial community structure(represented by the ratio of PLFA concentration in fungi to PLFA concentration in bacteria, and the ratio of PLFA concentration in gram-positive bacterial biomass to PLFA concentration in gram-negative bacterial biomass). However, the extreme precipitation events significantly increased soil microbial activity(represented by soil microbial biomass nitrogen and soil bacterial 16S rRNA gene copy numbers). Soil fungal community showed no significant response to precipitation events. According to the redundancy analysis, both soil microbial biomass nitrogen and soil ammonium nitrogen(NH4-N) were found to be significant in shaping soil microbial community. Acidobacteria, Actinobacteria and Proteobacteria were the dominant phyla in soil bacterial composition, and responded 展开更多
关键词 extreme precipitation event PHOSPHOLIPID fatty acid (PLFA) SOIL microbial community RT-qPCR SOIL bacteria SOIL fungi
Potential Use of a Poultry Manure Digestate as a Biofertiliser:Evaluation of Soil Properties and Lactuca sativa Growth
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作者 Natalia MóRTOLA Romina ROMANIUK +9 位作者 Vanina COSENTINO Maximiliano EIZA Patricia CARFAGNO Pedro RIZZO Patricia BRES Nicolás RIERA Marcos ROBA Mariano BUTTI Daiana SAINZ Lucrecia BRUTTI 《土壤圈:英文版》 SCIE CAS CSCD 2019年第1期60-69,共10页
Anaerobic digestion is a process that is widely used for the treatment of organic wastes. The digestate can be used as a soil amendment or crop fertiliser. The aims of our work were to evaluate 1) the physicochemical ... Anaerobic digestion is a process that is widely used for the treatment of organic wastes. The digestate can be used as a soil amendment or crop fertiliser. The aims of our work were to evaluate 1) the physicochemical composition and pathogen content in a digestate from poultry manure, according to international regulations, and 2) the effect of its soil application on the major chemical and biological soil properties and on the growth of Lactuca sativa. The experiment consisted of two groups of pots(with and without crop). Treatments applied to each group were as follows: low and high doses of digestate and inorganic fertiliser, and no application(control)(low dose: 70 kg nitrogen(N) ha-1 and 21 kg phosphorus(P) ha-1;high dose: 210 kg N ha-1 and 63 kg P ha-1). Soil samples were taken 7 and 34 d(harvest) after treatment applications. Heavy metal and pathogen contents in the digestate were below the upper limit values. Despite the high pH and electrical conductivity values of the digestate, both soil parameters presented acceptable values for crop growth. Although there were no initial increases in total inorganic N and available P in soil with digestate application, an increase in the fresh weight of crop was observed with the high dose application. This is probably associated with the slow nutrient release from the digestate during the development of the crop. Changes in the microbial community were temporary and occurred at the initial sampling stage of the experiment. 展开更多
关键词 anaerobic digestion crop yield ORGANIC FERTILISER ORGANIC waste SOIL amendment SOIL chemical PROPERTIES SOIL microbiological PROPERTIES
不同粒径处理的土壤全氮含量高光谱特征拟合模型 预览
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作者 王海江 刘凡 +2 位作者 YUNGER John A 崔静 马玲 《农业机械学报》 EI CAS CSCD 北大核心 2019年第2期195-204,共10页
采集新疆北疆棉田385个自然土壤样本,将筛选出的土壤样品分别过2、1、0.5、0.15 mm筛并测定其原始光谱反射率,利用支持向量机(Support vector machine,SVM)、偏最小二乘回归(Partial least squares regression,PLSR)和多元逐步线性回归(... 采集新疆北疆棉田385个自然土壤样本,将筛选出的土壤样品分别过2、1、0.5、0.15 mm筛并测定其原始光谱反射率,利用支持向量机(Support vector machine,SVM)、偏最小二乘回归(Partial least squares regression,PLSR)和多元逐步线性回归(Stepwise multiple linear regression,SMLR)方法对土壤原始光谱及其12种光谱变换数据分别构建土壤全氮含量的估测模型,并对模型精度进行检验。结果表明,土壤原始光谱特征在各个波段与全氮含量相关性都较差,不同形式的数据变换均能够提高光谱反射率与全氮含量的相关性,同一种数据变换形式在不同粒径处理中最大相关系数所对应的波段位置差异不大。从不同粒径处理的拟合精度来看,过筛粒径越小对全氮含量的估测精度越高,3种方法的最优拟合模型都是过0.15 mm筛的处理,其中SVM方法采用(lgR)′变换后,构建模型Rc^2为0.898 7,RMSE c为0.018 1,RPD为2.704 9,PLSR和SMLR方法均采用R′变换,构建模型的Rc^2分别为0.852 0和0.819 6,RMSE c分别为0.041 3和0.043 6,RPD分别为2.554 9和2.437 4,3种方法在该过筛处理下均能够很好地估测土壤全氮含量。用未参与建模的样本对3种最优模型进行验证,SVM、PLSR和SMLR模型的检验R 2分别为0.822 9、0.771 5和0.705 4,SVM方法优于PLSR和SMLR,模型具有较好的精度和稳定性,从模型的预测误差来看,土壤全氮含量越低其预测误差也越大,在氮素含量较低的情况下无法直接通过光谱反射特征准确反演。 展开更多
关键词 土壤 全氮含量 土壤粒径 高光谱 模型
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农田土壤机械压实修复研究 预览
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作者 周艳丽 《中国农机化学报》 北大核心 2019年第1期141-144,共4页
农田土壤机械压实是由机械作业引起的土壤结构破坏,导致土壤质量下降,具有累积效果。通过农机技术对压实土壤进行修复,可以改善土壤三相比,提高土壤质量。深松耕地土壤容重降低15.62%,土壤孔隙度提高7.7个百分点,孔隙比提高36.51%;土壤... 农田土壤机械压实是由机械作业引起的土壤结构破坏,导致土壤质量下降,具有累积效果。通过农机技术对压实土壤进行修复,可以改善土壤三相比,提高土壤质量。深松耕地土壤容重降低15.62%,土壤孔隙度提高7.7个百分点,孔隙比提高36.51%;土壤含水量正常年份可提高0.99个百分点,干旱季节可提高1.22个百分点,而多雨季节则降低0.8个百分点;土壤速效氮、速效磷、速效钾分别提高21.4%、18.04%、12.6%。除应用农机技术外,还可以使用农艺技术对压实土壤进行修复,通过增加土壤有机质含量、作物合理轮作等降低土壤容重,提高土壤孔隙度,修复土壤压实。 展开更多
关键词 土壤 农业机械 土壤压实 修复
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不同修复措施对砷污染土壤处理效果及土壤理化性质的影响 预览
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作者 卜庆国 李朝晖 +1 位作者 张姣 熊燕娜 《安徽农业科学》 CAS 2019年第6期85-87,共3页
通过稳定化处理、淋洗处理与生物修复处理砷污染土壤,探讨不同修复措施对土壤总砷水浸浓度、总砷酸浸浓度、容重、pH、质地、渗透系数与电导率的影响。结果表明:3种修复措施均对土壤总砷水浸与酸浸浓度产生显著影响,经稳定化处理、淋洗... 通过稳定化处理、淋洗处理与生物修复处理砷污染土壤,探讨不同修复措施对土壤总砷水浸浓度、总砷酸浸浓度、容重、pH、质地、渗透系数与电导率的影响。结果表明:3种修复措施均对土壤总砷水浸与酸浸浓度产生显著影响,经稳定化处理、淋洗处理与生物修复处理的污染土壤总砷水浸均值由1.10mg/L分别降低至0.05、0.48与0.92mg/L;经稳定化处理、淋洗处理与生物修复处理的污染土壤总砷酸浸均值由4.35mg/L分别降低至0.38、0.45与3.99mg/L。稳定化处理显著提高了土壤容重、pH、电导率,显著降低土壤渗透率系数,并使土壤质地由壤土变为砂土;淋洗处理显著提高土壤渗透系数,显著降低土壤pH;生物修复处理显著提高土壤渗透系数。 展开更多
关键词 砷污染 土壤 浸出浓度 土壤理化性质
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Phenotypic plasticity of Artemisia ordosica seedlings in response to different levels of calcium carbonate in soil
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作者 XUE Pingping ZHAO Xuelai +1 位作者 GAO Yubao HE Xingdong 《干旱区科学:英文版》 SCIE CSCD 2019年第1期58-65,共8页
Plant phenotypic plasticity is a common feature that is crucial for explaining interspecific competition, dynamics and biological evolution of plant communities. In this study, we tested the effects of soil CaCO3(calc... Plant phenotypic plasticity is a common feature that is crucial for explaining interspecific competition, dynamics and biological evolution of plant communities. In this study, we tested the effects of soil CaCO3(calcium carbonate) on the phenotypic plasticity of a psammophyte, Artemisia ordosica, an important plant species on sandy lands in arid and semi-arid areas of China, by performing pot experiments under different CaCO3 contents with a two-factor randomized block design and two orthogonal designs. We analyzed the growth responses(including plant height, root length, shoot-leaf biomass and root biomass) of A. ordosica seedlings to different soil CaCO3 contents. The results revealed that, with a greater soil CaCO3 content, A. ordosica seedlings gradually grew more slowly, with their relative growth rates of plant height, root length, shoot-leaf biomass and root biomass all decreasing significantly. Root N/P ratios showed significant negative correlations with the relative growth rates of plant height, shoot-leaf biomass and root length of A. ordosica seedlings;however, the relative growth rate of root length increased significantly with the root P concentration increased, showing a positive correlation. These results demonstrate that soil CaCO3 reduces the local P availability in soil, which produces a non-adaptive phenotypic plasticity to A. ordosica seedlings. This study should prove useful for planning and promoting the restoration of damaged/degraded vegetation in arid and semi-arid areas of China. 展开更多
关键词 ARTEMISIA ORDOSICA N/P ratio PHENOTYPIC plasticity relative growth rate SOIL CaCO3 SOIL P availability ARID and SEMI-ARID areas
不同类型生物炭混施对土壤磷素淋失的影响试验研究 预览
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作者 尹俊慧 李小英 《中国农学通报》 2019年第6期32-36,共5页
研究旨在将竹炭和木炭混施入土壤,比较分析不同生物炭处理对土壤磷素淋失的影响,为寻求更高效的生物炭土壤改良技术提供新的思路。基于土柱淋洗模拟试验,设置CK(不施生物炭和磷肥)、P(单施磷肥)、1:0(施磷肥和木炭)、0:1(施磷肥和竹炭)... 研究旨在将竹炭和木炭混施入土壤,比较分析不同生物炭处理对土壤磷素淋失的影响,为寻求更高效的生物炭土壤改良技术提供新的思路。基于土柱淋洗模拟试验,设置CK(不施生物炭和磷肥)、P(单施磷肥)、1:0(施磷肥和木炭)、0:1(施磷肥和竹炭)和1:1(施磷肥和按1:1混合的木炭、竹炭)5组处理,以不同填装容重和淋洗间隔进行两轮试验,测定淋溶液中正磷酸盐含量及pH值。结果表明:施用生物质炭可显著增加土壤pH值,有效抑制磷素淋失20%以上。竹炭抑制土壤磷素淋失的效果显著优于木炭,将木炭和竹炭以1:1的比例混施能够提高木炭对磷素淋失的抑制效果。不同类型生物炭混施技术在控制土壤磷素淋失方面具有良好的应用前景,为寻求更高效的生物炭土壤改良技术,应进一步加强对生物炭的性质、施用量、土壤类型和肥力状况等的综合试验研究。 展开更多
关键词 土壤 生物炭 土柱淋洗
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Nematode distribution in cultivated and undisturbed soils of Guinea Savannah and Semi-deciduous Forest zones of Ghana 预览
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作者 Obed Asiedu Charles Kodia Kwoseh +1 位作者 Haddish Melakeberhan Thomas Adjei-Gyapong 《地学前缘:英文版》 CAS CSCD 2019年第2期381-387,共7页
Climate change affects air temperature,sea levels as well as the soil and its ecosystem.The Guinea Savannah and Semi-deciduous Forest zones of Ghana are characterized by different climatic conditions and vegetative co... Climate change affects air temperature,sea levels as well as the soil and its ecosystem.The Guinea Savannah and Semi-deciduous Forest zones of Ghana are characterized by different climatic conditions and vegetative cover.Annual average temperature has been steadily increasing whilst annual total rainfall has been decreasing in both zones,and this has been causing a southward shift of the Savannah into the Forest zone.Soil organisms provide crucial ecosystem services which are required for sustainable agriculture and food production yet crop cultivation disturbs the soil ecosystem.The harsh conditions associated with the Savannah further expose the soil ecosystem to disturbance and loss of biodiversity which threatens food production and security.Soil nematodes are the most abundant animals in the soil and play a central and critical role in the soil food web complex.Studying the nematode community structure gives a reflection of the status of the entire soil ecosystem.Soil samples were taken from cultivated and natural landscapes in the Guinea Savannah and Semi-deciduous Forest agroecological zones to analyse the nematode community.Results from the study showed the Guinea Savannah zone recording warmer soil temperatures,lower organic matter percentage and lower nematode diversity(Genus Richness)as compared to the Semi-deciduous Forest zone.If the Savannah continues to shift southward,the Forest zone soil ecosystem risks disturbance and loss of biodiversity due to the harsh Savannah conditions.Our findings indicate that prevailing crop cultivation practices also disturb soil ecosystem in the two ecological zones which span across West Africa.A disturbed soil ecosystem endangers the future of food production and food security. 展开更多
关键词 Climate change GUINEA SAVANNAH Semi-deciduous Forest SOIL temperature SOIL NEMATODE diversity
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Spatial variability of soil water content and related factors across the Hexi Corridor of China
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作者 LI Xiangdong SHAO Ming’an +1 位作者 ZHAO Chunlei JIA Xiaoxu 《干旱区科学:英文版》 SCIE CSCD 2019年第1期123-134,共12页
Soil water content(SWC) is a key factor limiting ecosystem sustainability in arid and semi-arid areas of the Hexi Corridor of China, which is characterized by an ecological environment that is vulnerable to climate ch... Soil water content(SWC) is a key factor limiting ecosystem sustainability in arid and semi-arid areas of the Hexi Corridor of China, which is characterized by an ecological environment that is vulnerable to climate change. However, there is a knowledge gap regarding the large-scale spatial distribution of SWC in this region. The specific objectives of this study were to determine the spatial distribution patterns of SWC across the Hexi Corridor and identify the factors responsible for spatial variation of SWC at a regional scale. This study collected and analyzed SWC in the 0–100 cm soil profile from 109 field sampling sites(farmland, grassland and forestland) across the Hexi Corridor in 2017. We selected 17 factors, including land use, topography(latitude, longitude, elevation, slope gradient, and slope aspect), soil properties(soil clay content, soil silt content, soil bulk density, saturated hydraulic conductivity, field capacity, and soil organic carbon content), climate factors(mean annual precipitation, potential evaporation, and aridity index), plant characteristic(vegetation coverage) and planting pattern(irrigation or rain-fed), as possible environmental variables to analyze their effects on SWC. The results showed that SWC was 0.083(±0.067) g/g in the 0–100 cm soil profile and decreased in the order of farmland, grassland and forestland. The SWC in the upper soil layers(0–20, 20–40 and 40–60 cm) had obvious difference when the mean annual precipitation differed by 200 mm. The SWC decreased from southeast to northwest following the same pattern as precipitation, and had a moderate to strong spatial dependence in a large effective range(75–378 km). The SWC showed a similar distribution and had no significant difference between soil layers in the 0–100 cm soil profile. The principal component analysis showed that the mean annual precipitation, geographical position(longitude and latitude) and soil properties(soil bulk density and soil clay content) were the main factors dominating the varian 展开更多
关键词 SOIL water CONTENT spatial VARIABILITY geostatistical analysis SOIL CLAY CONTENT Hexi CORRIDOR
有机肥与化肥配施对土壤微生物及烟叶品质的影响 预览
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作者 潘义宏 顾毓敏 +5 位作者 夏贤仁 卢晓华 王瑞宝 刘有才 杨森 敖金成 《江西农业学报》 CAS 2019年第1期30-36,共7页
在曲靖市宣威烟区,通过田间试验研究了两种有机肥与无机肥按不同比例配施对植烟土壤综合肥力、土壤微生物数量、云烟105烟叶综合品质的影响.结果表明:氨基酸菜籽饼肥和甲壳素氨基酸有机肥与无机肥按不同比例配施均能在一定程度上提高土... 在曲靖市宣威烟区,通过田间试验研究了两种有机肥与无机肥按不同比例配施对植烟土壤综合肥力、土壤微生物数量、云烟105烟叶综合品质的影响.结果表明:氨基酸菜籽饼肥和甲壳素氨基酸有机肥与无机肥按不同比例配施均能在一定程度上提高土壤微生物数量和土壤综合肥力;在烤烟生长发育期间,所有处理植烟土壤中微生物数量均呈先增加后降低的变化趋势,且均在现蕾期达到最大值;与施用烟草专用复合肥(CK)相比,30%甲壳素氨基酸有机肥与70%无机肥混施处理能显著提高烤烟现蕾期土壤细菌、真菌和放线菌的数量(P<0.05),分别提高了490.90%、93.02%和39.58%;该配施处理还使植烟土壤综合肥力和烟叶综合品质分别较CK提高了22.64%和10.71%. 展开更多
关键词 土壤 综合肥力 有机肥 配施 土壤微生物 烤烟 综合品质
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河道疏浚底泥农用对土壤及水稻生长的影响 预览
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作者 钱建锋 《江苏水利》 2019年第3期40-43,共4页
通过对河道疏浚底泥的成分进行分析,合理判断疏浚底泥对水稻生长造成的影响,为提高底泥资源利用率提供科学合理的建议。在本试验中,分为无污染底泥和有污染底泥2组,对两份底泥样本以及所选择的土壤中的有机物和重金属进行分析。通过上... 通过对河道疏浚底泥的成分进行分析,合理判断疏浚底泥对水稻生长造成的影响,为提高底泥资源利用率提供科学合理的建议。在本试验中,分为无污染底泥和有污染底泥2组,对两份底泥样本以及所选择的土壤中的有机物和重金属进行分析。通过上述试验,可以得出以下结论:第一,不同污染底泥农用对土壤性状的影响主要表现为底泥比例与有机物质、碱解氮以及有效磷三者含量之间呈现出正比关系。第二,不同底泥对于水稻产量将会带来带来一定的影响。第三,无论底泥是否有无污染,底泥比例与水稻种重金属Cu含量呈现出相反的关系。 展开更多
关键词 河道疏浚 底泥 土壤 水稻生长
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贵州喀斯特山区典型人工林土壤矿质元素特征 预览
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作者 喻阳华 程雯 杨丹丽 《广西植物》 CAS CSCD 北大核心 2019年第1期108-116,共9页
为了阐明群落水平上的土壤矿质元素特征,该研究以贵州喀斯特山区典型人工林为对象,以金属元素和非金属元素进行类型划分,探讨了土壤矿质元素含量特征及其相关性。结果表明:该区典型人工林土壤矿质元素含量存在较大差异,且同一元素在不... 为了阐明群落水平上的土壤矿质元素特征,该研究以贵州喀斯特山区典型人工林为对象,以金属元素和非金属元素进行类型划分,探讨了土壤矿质元素含量特征及其相关性。结果表明:该区典型人工林土壤矿质元素含量存在较大差异,且同一元素在不同树种之间的变化幅度各异,锌、铬、铁、钛、铝、镁、镍、钴等的变化规律较为一致,钙、锶等的变化趋势较为相似,砷、硒、硅在桉树(Eucalyptus robusta)林、柏木(Cupressus funebris)林和枇杷(Eriobotrya japonica)林中的含量较高,硫、钠、氯等元素含量则相反;不同矿质元素随林分类型的变化规律不完全一致,表明植物根系对养分的提取和富集能力存在差异;矿质元素之间表现出一定程度的相关性,存在此消彼长的关系,不同矿质元素之间的相关关系各异,表现出增强或抑制效应,尤其以铁、钙等元素与其他元素的关系更为密切;矿质元素之间的互作效应及其计量平衡关系是分析元素特征的关键,是未来值得深入研究的科学问题。该研究结果有利于掌握养分元素积累特征与调控规律,对于该区域典型人工林土壤养分管理具有较强的理论和实践意义。 展开更多
关键词 人工林 土壤 矿质元素 相关性 贵州喀斯特山区
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碱熔-氢化物发生原子荧光光谱法测定土壤中的痕量锗 预览
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作者 马凤英 胡兰 赵玲 《现代农业科技》 2019年第2期134-135,共2页
本文通过对原子荧光仪器条件、磷酸用量、硼氢化钾及氢氧化钠浓度等试验条件进行优化,采用原子荧光光谱仪测定锗的含量。结果表明,该法的检出限为0.1μg/g,测定的8个国家标准物质与推荐值相符,且重复测定12次的相对误差≤2%。
关键词 土壤 氢化物原子荧光光谱法 碱熔
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典型肥料生产场地氨氮分布特征及风险控制目标确定 预览
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作者 谢雨呈 谭长银 +4 位作者 张朝 王积才 王梅 杨敏 郭观林 《环境科学研究》 EI CAS CSCD 北大核心 2019年第3期465-474,共10页
为探究肥料生产场地的NH3-N(氨氮)分布特征及环境风险,以我国某肥料生产场地为研究对象,在场地调查基础上,对场地土壤和地下水NH3-N的空间分布进行分析,并以人体健康和场地地下水为保护对象分别讨论了土壤NH3-N风险控制目标值的计算方法... 为探究肥料生产场地的NH3-N(氨氮)分布特征及环境风险,以我国某肥料生产场地为研究对象,在场地调查基础上,对场地土壤和地下水NH3-N的空间分布进行分析,并以人体健康和场地地下水为保护对象分别讨论了土壤NH3-N风险控制目标值的计算方法.结果表明:①目标场地土壤中w(NH3-N)为0.03~15000mg/g,水平方向上高值区集中分布于核心生产区及原辅料堆场,垂向上总体表现为由上至下随深度增加呈先逐步升高后降低的趋势,并且富集于人工填土与原状粉质黏土交界处,粉质黏土阻碍NH3-N向下迁移,并随地层结构变化其迁移深度不同.②场地上层滞水和潜水中ρ(NH3-N)分别为19.10~3320和0.03~219mg/L,超标率分别为100%和57.89%,并且地下水与土壤的NH3-N在水平空间分布上具有重叠特征.③因NH3-N主要通过呼吸吸入挥发性气体产生暴露,并且仅有经呼吸暴露的毒性参数,故采用《污染场地风险评估技术导则》中经呼吸暴露途径的非致癌效应风险控制值计算模型来计算土壤NH3-N的控制目标,通过代入场地实测土壤Kd(土-水分配系数),得到居住用地下的土壤NH3-N控制目标值为9195mg/kg;若考虑保护地下水水质安全,据三相或两相平衡模型耦合NH3-N在包气带衰减和地下水稀释作用,当目标场地地表无积水的入渗条件下得到的控制目标值为6203mg/kg;当地层从上至下呈饱和含水条件时,土壤NH3-N控制目标为811mg/kg.计算值可用作不同场地进行土壤NH3-N风险管控的参考目标,实际应用中可结合不同地块环境条件、不同受体和保护目标,选择相应的风险控制值对场地进行风险管控.此外,土壤和地下水的NH3-N污染控制均可考虑采用工程措施和制度控制来进行. 展开更多
关键词 污染场地 土壤 地下水 氨氮 污染特征 控制目标值
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超声波提取-气相色谱氢火焰测定土壤中六溴环十二烷 预览
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作者 王馨蕾 崔兆杰 《环境科学研究》 EI CAS CSCD 北大核心 2019年第3期493-499,共7页
HBCD(六溴环十二烷,hexabromocyclododecane)是一种常用的溴代阻燃剂,其对环境和生物体造成的影响已被定性为持久性有机污染物.为了建立超声波提取、气相色谱检测土壤中w(HBCD)的方法,分别对超声波提取HBCD条件及气相色谱检测HBCD参数... HBCD(六溴环十二烷,hexabromocyclododecane)是一种常用的溴代阻燃剂,其对环境和生物体造成的影响已被定性为持久性有机污染物.为了建立超声波提取、气相色谱检测土壤中w(HBCD)的方法,分别对超声波提取HBCD条件及气相色谱检测HBCD参数进行优化,并对超声波提取法与索氏提取法进行了比较.结果表明:①最佳超声波提取土壤中HBCD条件为以体积比为1∶1的正己烷:丙酮溶液为提取溶剂,60℃水浴振荡,超声波提取50min.②气相色谱优化后提取HBCD的最佳分离条件为进样口温度240℃;初始温度90℃,保留1min;升温程序为90℃时以15℃/min升温至160℃,保留2min,再以10℃/min升至220℃,保留2min,最后以5℃/min升至280℃,保留3min;分流模式为不分流;以氮气为载气;进样量为1μL;FID检测器温度为300℃.③HBCD在土壤中的平均回收率可达97.1%,相对标准偏差为3.5%,方法精密度高.④与索氏提取方法相比,超声波提取法提取时间短、样品用量少、灵敏度高,并且方法重现性和精密度较好,能更有效地分析土壤中w(HBCD).研究显示,场地土壤中w(HBCD)平均值为0.757mg/kg,相对标准偏差为4.22%(小于5%),超声波提取及气相色谱检测土壤中HBCD的方法准确度高、重现性好,对分析土壤中HBCD更加简便快捷. 展开更多
关键词 六溴环十二烷 气相色谱 超声波提取 土壤
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上消化道癌前病变患者舌苔与土壤菌群相关性初步分析 预览
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作者 孙娴 徐静 +4 位作者 华召来 成颖 陆斌 詹瑧 张军峰 《现代肿瘤医学》 CAS 2019年第6期1009-1016,共8页
目的:探讨扬中地区上消化道癌前病变患者舌苔与土壤菌群的相关性。方法:收集22例上消化道癌前病变患者的舌苔和自留地土壤,采用16SrDNA高通量测序检测菌群,生物信息学分析菌群多样性、菌群结构、共生关系等。结果:舌苔菌群多样性和丰富... 目的:探讨扬中地区上消化道癌前病变患者舌苔与土壤菌群的相关性。方法:收集22例上消化道癌前病变患者的舌苔和自留地土壤,采用16SrDNA高通量测序检测菌群,生物信息学分析菌群多样性、菌群结构、共生关系等。结果:舌苔菌群多样性和丰富度均显著低于土壤,菌群组成显著不同。舌苔与土壤之间有17个分类单元(1门、2纲、3目、3科、4属和4种)显著相关。然而,舌苔与土壤菌群预测功能中脂质运输与代谢、翻译后修饰-蛋白翻转-蛋白伴侣、信号转导机制、防御机制等均为显著负相关,胞内运输-分泌-囊泡运输为显著正相关。结论:舌苔与土壤菌群存在相关性,土壤菌群可能是扬中地区上消化道癌地域性高发的关键因素。 展开更多
关键词 上消化道癌前病变 舌苔 自留地 土壤 微生态
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Effects of biochar-based fertilizers on nutrient leaching in a tobacco-planting soil
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作者 Yunlong Li Jianzhong Cheng +4 位作者 Xinqing Lee Yi Chen Weichang Gao Wenjie Pan Yuan Tang 《中国地球化学学报:英文版》 EI CAS CSCD 2019年第1期1-7,共7页
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 soil nutrient leaching in agricultural soil... 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 soil nutrient leaching in agricultural soils.We conducted a soil column leaching experiment to study the effects of BF on the leaching of total nitrogen (TN),total phosphorus,and total potassium (TK)in tobacco soils.The distribution characteristics of NH4+-N,available P,and available K in soil profiles were analyzed after the application of BF.Biochar was prepared by pyrolysis of fluecured tobacco stems.It was applied at four levels,0%,3%,9%,and 15%(w/w),respectively,to the compound fertilizer.Compared with the control,the leaching loss of soil TN decreased by 8.36%,6.72%,and 6.45%,and the loss of soil TK decreased by 9.18%,9.31%and 11.82%in the 3%,9%,and 15% BF treatments,respectively.However,BF had no significant effect on the P leaching due to the low movement of P in the soil profile.In addition,the BF addition increased the immobilization of NH4+-N,available P,and available K in the soil profile.These results indicate that addition of BF to a tobacco-planting soil reduced nutrient leaching,and suggest that BF could be an effective method of applying biochar to agriculture fields. 展开更多
关键词 Biochar-based fertilizer Soil column NUTRIENT elements Leaching loss IMMOBILIZATION
云龙水库周边土壤中重金属的危害评价 预览
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作者 徐永梅 字润祥 卞世闻 《环境科学导刊》 2019年第1期88-91,共4页
在云龙水库周边选取5个监测点位,测定土壤中的Cu、Zn、Pb、Cd、Cr和As6种重金属元素的含量,利用地质累积指数法和生态危害指数法进行分析。结果表明:云龙水库周边土壤中的重金属指标地质累积指数Cd和As处于轻度级别;Cu、Zn、Pb、Cr处于... 在云龙水库周边选取5个监测点位,测定土壤中的Cu、Zn、Pb、Cd、Cr和As6种重金属元素的含量,利用地质累积指数法和生态危害指数法进行分析。结果表明:云龙水库周边土壤中的重金属指标地质累积指数Cd和As处于轻度级别;Cu、Zn、Pb、Cr处于偏中度级别;重金属的污染度单因子六项均处于低度污染,多因子也处于低度污染;生态风险指数单个金属指标和多个金属复合指标均处于轻微生态危害状态,土壤状况较好。 展开更多
关键词 土壤 重金属 危害评价 云龙水库
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超声萃取高效液相色谱法测定土壤中乙草胺的残留量 预览
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作者 范小振 王嘉莉 张淑华 《沧州师范学院学报》 2019年第1期11-15,共5页
建立了一种从土壤中超声提取乙草胺并采用高效液相色谱法测定其残留量的分析方法.选用正己烷∶丙酮(配比为4∶1)为萃取剂,超声振荡萃取时间为20min,使用BDS Hypersil C18(4.6mm×250mm,5μm)色谱柱,以乙腈∶水=70∶30为流动相,流速... 建立了一种从土壤中超声提取乙草胺并采用高效液相色谱法测定其残留量的分析方法.选用正己烷∶丙酮(配比为4∶1)为萃取剂,超声振荡萃取时间为20min,使用BDS Hypersil C18(4.6mm×250mm,5μm)色谱柱,以乙腈∶水=70∶30为流动相,流速为1mL·min^-1,紫外检测波长为210nm.测定结果显示:乙草胺的保留时间为4.875min,线性相关系数为0.9984;相对标准偏差(RSD)为3.5%;在四个梯度质量浓度水平上,平均回收率是97.09%,该分析方法的检出限为0.18ng·mL^-1,该方法简单快捷,灵敏度高,准确性好,可作为乙草胺的检测方法. 展开更多
关键词 超声萃取 高效液相色谱法 乙草胺 土壤 残留分析
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