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Salt Contents in Soils Under Plastic Greenhouse Gardening in China 被引量:67
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作者 LIWENQING S.VANDERZEE 《Pedosphere》 SCIE CAS CSCD 2001年第4期359-367,共9页
Field experiments were conducted on three main soils, brown soil, meadow soil and cinnamon soil, of Shandong Province to study the effect of plastic greenhouse gardening on soil salt contents. As compared to the open ... Field experiments were conducted on three main soils, brown soil, meadow soil and cinnamon soil, of Shandong Province to study the effect of plastic greenhouse gardening on soil salt contents. As compared to the open fields, the soil nutrient contents in the fields under plastic greenhouse gardening all increased significantly. The organic matter, quickly available N and P increases were extremely significant and the quickly available K increase was also significant. Along with the nutrient increases the soil salt contents increased clearly in all the soils investigated not only in the top layer but also in the deeper layers, being extremely significant in the 0~10 cm layer and significant in the 10~40 cm layers. The salt contents in the plastic greenhouses had significant correlations with the soil available nitrogen and phosphorous. Soils with longer plastic greenhouse gardening time tended to have more salt. The plastic greenhouse soils contained less CO-3~(2-) and much more NO-3 than the open soils, which indicated a higher influence of human intervention in plastic greenhouses. Among the constituent ions, Cl~(-), NO-3~(-) , Ca~(2+) and Mg~(2+) had positive while HCO-3~(-) had negative significant or extremely significant correlations with total salt, with correlation coefficients being 0.66*, 0.80**, 0.92**, 0.80** and -0.64* , respectively. Nitrate decreased from the top to deeper layers both in the plastic greenhouses and in the open fields. The plastic greenhouse soils contained much more nitrate than the open fields in every layer and even the nitrate contents of the 80~l00 cm layer were still several times those of the top layer in the open fields. The main reason for the salt increases was considered to be the inappropriate fertilization and selective absorption of nutrients by plants in the plastic greenhouses. The methods recommended to avoid soil salt increase in the plastic greenhouses were to apply fertilizers rationally according to the soils, vegetables and fertilizer properties and to adopt a good intercropping or rotation system. 展开更多
关键词 FERTILIZATION NITRATE plastic greenhouse salt content VEGETABLE
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Influences of soil moisture and salt content on loess shear strength in the Xining Basin, northeastern Qinghai-Tibet Plateau 被引量:11
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作者 FU Jiang-tao HU Xia-song +5 位作者 LI Xi-lai YU Dong-mei LIU Ya-bin YANG You-Qing QI Zhao-xin LI Shu-xia 《Journal of Mountain Science》 SCIE CSCD 2019年第5期1184-1197,共14页
Moisture and salt content of soil are the two predominant factors influencing its shear strength. This study aims to investigate the effects of these two factors on shear strength behavior of loess in the Xining Basin... Moisture and salt content of soil are the two predominant factors influencing its shear strength. This study aims to investigate the effects of these two factors on shear strength behavior of loess in the Xining Basin of Northeast Qinghai-Tibet Plateau, where such geological hazards as soil erosion, landslides collapse and debris flows are widespread due to the highly erodible loess. Salinized loess soil collected from the test site was desalinized through salt-leaching in the laboratory. The desalinized and oven-dried loess samples were also artificially moisturized and salinized in order to examine how soil salinity affects its shear strength at different moisture levels. Soil samples prepared in different ways(moisturizing, salt-leaching, and salinized) were measured to determine soil cohesion and internal friction angle. The results show that salt-leaching up to 18 rounds almost completely removed the salt content and considerably changed the physical components of loess, but the soil type remained unchanged. As salt content increases from 0.00% to 12.00%, both the cohesion and internal friction angle exhibit an initial decrease and then increase with salt content. As moisture content is 12.00%, the salt content threshold value for both cohesion and internal friction angle is identified as 3.00%. As the moisture content rises to 16.0% and 20.00%, the salt content threshold value for cohesion is still 6.00%, but 3.00% for internal friction angle. At these thresholds soil shear strength is the lowest, below which it is inversely related to soil salinity. Beyond the thresholds, however, the relationship is positive. Dissimilar to salinity, soil moisture content exerts an adverse effect on shear strength of loess. The findings of this study can provide a valuable guidance on stabilizing the engineering properties of salinized loess to prevent slope failures during heavy rainfall events. 展开更多
关键词 Salinized LOESS Desalinized LOESS salt-leaching Shear strength indices Moisture content salt content
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Derivation of salt content in salinized soil from hyperspectral reflectance data: A case study at Minqin Oasis, Northwest China 被引量:3
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作者 QIAN Tana Atsushi TSUNEKAWA +3 位作者 PENG Fei Tsugiyuki MASUNAGA WANG Tao LI Rui 《Journal of Arid Land》 SCIE CSCD 2019年第1期111-122,共12页
Soil salinization is a serious ecological and environmental problem because it adversely affects sustainable development worldwide, especially in arid and semi-arid regions. It is crucial and urgent that advanced tech... Soil salinization is a serious ecological and environmental problem because it adversely affects sustainable development worldwide, especially in arid and semi-arid regions. It is crucial and urgent that advanced technologies are used to efficiently and accurately assess the status of salinization processes. Case studies to determine the relations between particular types of salinization and their spectral reflectances are essential because of the distinctive characteristics of the reflectance spectra of particular salts. During April 2015 we collected surface soil samples(0–10 cm depth) at 64 field sites in the downstream area of Minqin Oasis in Northwest China, an area that is undergoing serious salinization. We developed a linear model for determination of salt content in soil from hyperspectral data as follows. First, we undertook chemical analysis of the soil samples to determine their soluble salt contents. We then measured the reflectance spectra of the soil samples, which we post-processed using a continuum-removed reflectance algorithm to enhance the absorption features and better discriminate subtle differences in spectral features. We applied a normalized difference salinity index to the continuum-removed hyperspectral data to obtain all possible waveband pairs. Correlation of the indices obtained for all of the waveband pairs with the wavebands corresponding to measured soil salinities showed that two wavebands centred at wavelengths of 1358 and 2382 nm had the highest sensitivity to salinity. We then applied the linear regression modelling to the data from half of the soil samples to develop a soil salinity index for the relationships between wavebands and laboratory measured soluble salt content. We used the hyperspectral data from the remaining samples to validate the model. The salt content in soil from Minqin Oasis were well produced by the model. Our results indicate that wavelengths at 1358 and 2382 nm are the optimal wavebands for monitoring the concentrations of chlorine and sulphate compounds, the predominant salts at Minqin Oasis. Our modelling provides a reference for future case studies on the use of hyperspectral data for predictive quantitative estimation of salt content in soils in arid regions. Further research is warranted on the application of this method to remotely sensed hyperspectral data to investigate its potential use for large-scale mapping of the extent and severity of soil salinity. 展开更多
关键词 SALINITY index soil salt content spectral reflectance waveband PAIRS ARID regions
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Monitoring Soil Salt Content Using HJ-1A Hyperspectral Data: A Case Study of Coastal Areas in Rudong County, Eastern China 被引量:5
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作者 LI Jianguo PU Lijie +5 位作者 ZHU Ming DAI Xiaoqing XU Yan CHEN Xinjian ZHANG Lifang ZHANG Runsen 《Chinese Geographical Science》 SCIE CSCD 2015年第2期213-223,共11页
Hyperspectral data are an important source for monitoring soil salt content on a large scale. However, in previous studies, barriers such as interference due to the presence of vegetation restricted the precision of m... Hyperspectral data are an important source for monitoring soil salt content on a large scale. However, in previous studies, barriers such as interference due to the presence of vegetation restricted the precision of mapping soil salt content. This study tested a new method for predicting soil salt content with improved precision by using Chinese hyperspectral data, Huan Jing-Hyper Spectral Imager(HJ-HSI), in the coastal area of Rudong County, Eastern China. The vegetation-covered area and coastal bare flat area were distinguished by using the normalized differential vegetation index at the band length of 705 nm(NDVI705). The soil salt content of each area was predicted by various algorithms. A Normal Soil Salt Content Response Index(NSSRI) was constructed from continuum-removed reflectance(CR-reflectance) at wavelengths of 908.95 nm and 687.41 nm to predict the soil salt content in the coastal bare flat area(NDVI705 < 0.2). The soil adjusted salinity index(SAVI) was applied to predict the soil salt content in the vegetation-covered area(NDVI705 ≥ 0.2). The results demonstrate that 1) the new method significantly improves the accuracy of soil salt content mapping(R2 = 0.6396, RMSE = 0.3591), and 2) HJ-HSI data can be used to map soil salt content precisely and are suitable for monitoring soil salt content on a large scale. 展开更多
关键词 soil salt content normalized differential vegetation index(NDVI) hyperspectral data Huan Jing-Hyper Spectral Imager(HJ-HSI) coastal area eastern China
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Effects of Storage and Cooking on the lodine Content in lodized Salt and Study on Monitoring lodine Content in Iodized Salt 被引量:2
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作者 WANG GUANG-YA ZHOU RUI-HUA +1 位作者 WANG ZHU SHI LEI and SUN MING(Departmens of Food Chemistry, Institute of Natrition and Food Hygiene,Chinese Academy of Preventive Medicine, Beijing 100050, China) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1999年第1期1-9,共9页
In order to ensure that the intake of iodine from iodized salt is adequate, the effects of cooking, storage and iedination on iodine content in iodized salt have been studied. For moni toring the analytical Performanc... In order to ensure that the intake of iodine from iodized salt is adequate, the effects of cooking, storage and iedination on iodine content in iodized salt have been studied. For moni toring the analytical Performance, a qoality control exawhnation was also undertaken. The loss of iodine was greater when salt was stored in plastic bag than in glass bottle. The loss was greater in fortified salt stored at 37℃ and under 76% humidity than in that at 20 ~ 25℃ and under lower humidity. The retention of iodine varied with the kind of has and also was influenced by the water content of cooked food. In general, the retention of iodine during cooking varied considerably (from 36. 6% to 86. 1 % ). The iodine concentration in salts varied greater from 3.0 to 100.3 mg/kg in salt for markets, and from 0 to 90.0 mg/kg in salts for households. 48. 3 % of samples from markets were found to be in compliance with national standards (30 ~ 50 mg/kg), and 72.0% of samples from households were in compliance with national standartl (20 ~ 50 mg/kg). Analytical data collected from 8 of the cooperative laheratories foran analytical reference material showed a 95% codridence interval of the population mean for both precision and accuracy, falling within X± 2SD and passing quality control exdrination 展开更多
关键词 Effects of Storage and Cooking on the lodine content in lodized salt and Study on Monitoring lodine content in Iodized salt
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Quantitative retrieval of soil salt content based on measured spectral data
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作者 HanChen Duan Tao Wang +2 位作者 Xian Xue CuiHua Huang ChangZhen Yan 《Research in Cold and Arid Regions》 CSCD 2016年第6期507-515,共9页
Choosing the Minqin Oasis, located downstream of the Shiyang River in Northwest China, as the study area, we used field-measured hyperspectral data and laboratory-measured soil salt content data to analyze the charact... Choosing the Minqin Oasis, located downstream of the Shiyang River in Northwest China, as the study area, we used field-measured hyperspectral data and laboratory-measured soil salt content data to analyze the characteristics of saline soil spectral reflectance and its transformation in the area, and elucidated the relations between the soil spectral re-flectance, reflectance transformation, and soil salt content. In addition, we screened sensitive wavebands. Then, a multiple linear regression model was established to predict the soil salt content based on the measured spectral data, and the accuracy of the model was verified using field-measured salinity data. The results showed that the overall shapes of the spectral curves of soils with different degrees of salinity were consistent, and the reflectance in visible and near-infrared bands for salinized soil was higher than that for non-salinized soil. After differential transformation, the correlation coefficient between the spectral reflectance and soil salt content was obviously improved. The first-order differential transformation model based on the logarithm of the reciprocal of saline soil spectral reflectance produced the highest accuracy and stability in the bands at 462 and 636 nm; the determination coefficient was 0.603, and the root mean square error was 5.407. Thus, the proposed model provides a good reference for the quantitative extraction and monitoring of regional soil salinization. 展开更多
关键词 spectral reflectance soil salt content SALINIZATION multiple linear regression Minqin Oasis
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A preliminary study on an upper ocean heat and salt content of the western Pacific warm pool region
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作者 Xiaoxin Yang Xiaofen Wu +1 位作者 Zenghong Liu Chunxin Yuan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第3期60-71,共12页
On the basis of Argo profile data of the temperature and salinity from January 2001 to July 2014, the spatial distributions of an upper ocean heat content(OHC) and ocean salt content(OSC) of the western Pacific warm p... On the basis of Argo profile data of the temperature and salinity from January 2001 to July 2014, the spatial distributions of an upper ocean heat content(OHC) and ocean salt content(OSC) of the western Pacific warm pool(WPWP) region and their seasonal and interannual variations are studied by a cyclostationary empirical orthogonal function(CSEOF) decomposition, a maximum entropy spectral analysis, and a correlation analysis.Probable reasons for variations are discussed. The results show the following.(1) The OHC variations in the subsurface layer of the WPWP are much greater than those in the surface layer. On the contrary, the OSC variations are mainly in the surface layer, while the subsurface layer varies little.(2) Compared with the OSC, the OHC of the WPWP region is more affected by El Ni?o-Southern Oscillation(ENSO) events. The CSEOF analysis shows that the OHC pattern in mode 1 has strong interannual oscillation, with eastern and western parts opposite in phase. The distribution of the OSC has a positive-negative-positive tripole pattern. Time series analysis shows that the OHC has three phase adjustments with the occurrence of ENSO events after 2007, while the OSC only had one such adjustment during the same period. Further analysis indicates that the OHC variations are mainly caused by ENSO events, local winds, and zonal currents, whereas the OSC variations are caused by much more complex reasons. Two of these, the zonal current and a freshwater flux, have a positive feedback on the OSC change in the WPWP region. 展开更多
关键词 ocean HEAT content salt content the western PACIFIC WARM pool ARGO data
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Water Absorption Capcapability and Moisture Content Seasonal Changing of Salt-Crust in Lop Nur Dry Lake
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作者 KONG Deyong LI Baoguo +3 位作者 MA Lichun JIANG Ping'an WU Hongqi LIU Hongpeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期183-184,共2页
The Lop Nur dry salt lake,Xinjiang province,is charactered by typical physiognomy salt-crust,located in39.6-41.3N.latitude and 89.6-91.4E.longitude.The thickness of salt-crust is about from 20 cm to 100 cm,and
关键词 Lop Nur Dry Lake salt-Crust Moisture content Water Absorption Capcapability
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Effects of Groundwater with Various Salinities on Evaporation and Redistribution of Water and Salt in Saline-sodic Soils in Songnen Plain,Northeast China
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作者 ZHU Wendong ZHAO Dandan +6 位作者 YANG Fan WANG Zhichun DONG Shide AN Fenghua MA Hongyuan ZHANG Lu TIBOR Tóth 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1141-1152,共12页
Groundwater mineralization is one of the main factors affecting the transport of soil water and salt in saline-sodic areas.To investigate the effects of groundwater with different levels of salinity on evaporation and... Groundwater mineralization is one of the main factors affecting the transport of soil water and salt in saline-sodic areas.To investigate the effects of groundwater with different levels of salinity on evaporation and distributions of soil water and salt in Songnen Plain,Northeast China,five levels of groundwater sodium adsorption ration of water(SARw)and total salt content(TSC mmol/L)were conducted in an oil column lysimeters.The five treated groundwater labeled as ST0:0,ST0:10,ST5:40,ST10:70 and ST20:100,were prepared with NaCl and CaCl2 in proportion,respectively.The results showed the groundwater evaporation(GWE)and soil evaporation(SE)increased firstly and then decreased with the increase of groundwater salinity.The values of GWE and SE in ST10:70 treatment were the highest,which were 2.09 and 1.84 times the values in the ST0:0 treatment with the lowest GWE and SE.There was a positive linear correlation between GWE and the Ca^(2+)content in groundwater,with R^(2)=0.998.The soil water content(SWC)of ST0:0 treatment was significantly(P<0.05)less than those of other treatments during the test.The SWC of the ST0:0 and ST0:10 treatments increased with the increase of soil depth,while the other treatments showed the opposite trend.Statistical analysis indicated the SWC in the 0–60 cm soil layer was positively correlated with the groundwater TSC and its ion contents during the test.Salt accumulation occurred in the topsoil and the salt accumulation in the 0–20 cm soil layer was significantly(P<0.05)greater than that in the subsoil.This study revealed the effects of the salinity level of groundwater,especially the Ca^(2+)content and TSC of groundwater,on the GWE and distributions of soil water and salt,which provided important support for the prevention and reclamation of soil salinization and sodificaton in shallow groundwater regions. 展开更多
关键词 groundwater evaporation sodium adsorption ratio total salt content ion composition soil salinization water and salt dynamics Songnen Plain China
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基于透射图像的高压脉动腌制咸鸭蛋含盐量检测
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作者 白竣文 靳家欣 +3 位作者 孙力 梁小祥 田潇瑜 蔡健荣 《农业工程学报》 EI CAS CSCD 北大核心 2024年第8期245-253,共9页
含盐量是衡量咸鸭蛋品质的重要指标。为了利用机器视觉技术实现高压脉动腌制咸鸭蛋含盐量的无损检测。该研究采用工业相机和透射光源搭建咸鸭蛋的透射图像采集装置。采用图像整体特征和长轴截面光强度特征两种特征提取方法,利用多元线... 含盐量是衡量咸鸭蛋品质的重要指标。为了利用机器视觉技术实现高压脉动腌制咸鸭蛋含盐量的无损检测。该研究采用工业相机和透射光源搭建咸鸭蛋的透射图像采集装置。采用图像整体特征和长轴截面光强度特征两种特征提取方法,利用多元线性回归、支持向量机回归两种算法,建立对蛋清、蛋黄及全蛋含盐量以及蛋黄指数的定量预测模型。结果表明,随着咸鸭蛋腌制时间的增加,其透光性显著提高。同时,透射图像蛋黄的所在视野区域会随着含盐量的增加而呈现规律性的变化。基于图像整体特征建立的蛋清、蛋黄、全蛋含盐量模型较优,在蛋黄指数预测下基于长轴截面光强度特征所建模型较优。其中,基于图像整体特征所建立的蛋黄含盐量支持向量机回归(support vector regression,SVR)模型最优,测试集相关系数(test set correlation coefficient,Rp)、测试集均方根误差(root mean square error of prediction,RMSEp)、相对分析误差(residual predictive deviation,RPD)分别达到0.8460、0.3416、1.898;基于长轴截面光强度特征建立的蛋黄指数多元线性回归(multiple linear regression,MLR)模型最优,测试集相关系数Rp、均方根误差RMSEp、相对分析误差RPD分别为0.8318、0.0743、1.916。该研究结果为咸鸭蛋含盐量的快速检测提供理论依据和技术支持。 展开更多
关键词 透射图像 咸鸭蛋 含盐量 机器视觉 无损检测
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基于多臂结构抗高温高盐降滤失剂的合成及作用机制
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作者 张颖 余维初 +3 位作者 丁飞 舒文明 吴爱斌 丁伟俊 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期149-159,共11页
以季戊四醇烯丙基醚为核心,合成具有多臂结构的超支化聚合物降滤失剂JHPAN,研究和分析JHPAN配制的钻井液在高温、高盐条件下的流变性能、降滤失性能和降滤失作用机制。结果表明:在加量(质量分数)为1.0%时,220℃老化前后,淡水浆的表观黏... 以季戊四醇烯丙基醚为核心,合成具有多臂结构的超支化聚合物降滤失剂JHPAN,研究和分析JHPAN配制的钻井液在高温、高盐条件下的流变性能、降滤失性能和降滤失作用机制。结果表明:在加量(质量分数)为1.0%时,220℃老化前后,淡水浆的表观黏度分别为10.5和10.0 mPa·s,塑性黏度分别为9.0和11.0 mPa·s,动切力分别为1.5和1.0 Pa;在加量为1.0%时,220℃老化16 h后,饱和NaCl盐水浆的API滤失量和高温高压滤失量分别为11.8和25.5 mL;JHPAN的多臂结构中含有大量的吸附基团和抗温耐盐基团有助于钻井液高温、高盐环境下形成致密的泥饼,从而提升其降滤失效果。 展开更多
关键词 钻井液 高温 高盐 超支化聚合物 降滤失剂
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滨海黏质盐渍土饱和泥浆与不同土水比土壤浸提液电导率的响应关系分析
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作者 王璐 胡鑫慧 +4 位作者 张岸清 郭洪海 郭徽 刘振林 贾曦 《山东农业科学》 北大核心 2024年第6期152-158,共7页
为统一和精准判定耐盐作物种植地块的土壤盐渍化程度,并针对饱和泥浆制备时饱和点的不确定性及其电导率测定的不稳定性等问题,本试验采用室内化验与统计分析方法,系统研究饱和泥浆与饱和土壤溶液两者间含水量和电导率的响应关系,以及饱... 为统一和精准判定耐盐作物种植地块的土壤盐渍化程度,并针对饱和泥浆制备时饱和点的不确定性及其电导率测定的不稳定性等问题,本试验采用室内化验与统计分析方法,系统研究饱和泥浆与饱和土壤溶液两者间含水量和电导率的响应关系,以及饱和泥浆电导率、全盐含量与土水比1∶0.5、1∶1、1∶2.5、1∶3.5、1∶5土壤浸提液电导率与全盐含量的响应和换算关系。结果表明:在滨海黏质盐渍土区,利用计算田间土壤孔隙度得到的饱和土壤溶液含水量、电导率不能直接代替饱和泥浆含水量、电导率,尽管二者的响应关系达到极显著水平;饱和泥浆电导率、全盐含量分别与土水比1∶1和1∶0.5土壤浸提液的数值差异最小,且与土水比1∶0.5~1∶5间各处理土壤浸提液的相应指标均呈极显著的响应关系;饱和泥浆电导率与土水比1∶5土壤浸提液的电导率、饱和泥浆全盐含量与土水比1∶1土壤浸提液全盐含量相关性最高,可分别用最佳拟合线性模型进行换算,模型分别为ECe(mS/cm)=5.406EC1∶5-0.284 4,TSe(g/kg)=0.836 4TS1∶1-0.135 9。 展开更多
关键词 黏质盐渍土 土水比 饱和泥浆 土壤浸提液 电导率 全盐含量
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盐渍土路基含盐量的演化规律研究
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作者 李飞 于振涛 《地下空间与工程学报》 CSCD 北大核心 2024年第S01期344-349,共6页
虽然目前针对盐渍土的研究比较多,但基本上都集中在项目勘察设计及建设期,对利用盐渍土填筑的路堤中含盐量随时间变化的规律,国内外研究还比较少。为了探究盐渍土路基填料中含盐量随时间的变化规律,为改建项目中盐渍土路基设计提供理论... 虽然目前针对盐渍土的研究比较多,但基本上都集中在项目勘察设计及建设期,对利用盐渍土填筑的路堤中含盐量随时间变化的规律,国内外研究还比较少。为了探究盐渍土路基填料中含盐量随时间的变化规律,为改建项目中盐渍土路基设计提供理论支撑,本文依托巴基斯坦罗赫里至木尔坦段既有铁路提速改造项目,通过现场调查及大量现场试验,对比分析既有路基填料及两侧原状土中含盐量,总结出盐渍土路基变化规律。结果表明:采用盐渍土填筑的路堤,路基填土中含盐量随着时间推移逐渐降低,逐渐过渡为非盐渍土;对于新建路基采用盐渍土填筑时,采用加宽路基面、放缓路堤坡率等工程措施,同时优先安排施工,静置浸润后,可有效降低路基填料中含盐量,直接采用盐渍土填筑路基既节约工程投资,又能确保路基的安全稳定。 展开更多
关键词 盐渍土 既有线 含盐量 毛细水上升
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芡实对沿淮富营养化水体的净化效果研究
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作者 陈毛华 杨永学 刘坤 《中国农学通报》 2024年第22期66-71,共6页
为了解乡土水生植物芡实对沿淮农村富营养化河流净化效果,在模拟沿淮农村地区富营养化河流的水池中种植芡实,定期监测水体中的总氮(TN)、氨氮(NH_(4)^(+)-N)、总磷(TP)、化学需氧量(COD_(Cr))、酸碱度(pH)、可溶性盐含量(EC)、溶解氧(DO... 为了解乡土水生植物芡实对沿淮农村富营养化河流净化效果,在模拟沿淮农村地区富营养化河流的水池中种植芡实,定期监测水体中的总氮(TN)、氨氮(NH_(4)^(+)-N)、总磷(TP)、化学需氧量(COD_(Cr))、酸碱度(pH)、可溶性盐含量(EC)、溶解氧(DO)的数值变化,综合分析芡实对富营养化河流的净化效果。结果表明,芡实作为沿淮地区乡土水生植物,对富营养化的河流有着净化作用。芡实在生长过程中能吸收水体95.53%~98.45%的NH_(4)^(+)-N和99.50%~99.65%的TP,净化效果好。芡实对富营养河流中TN和COD_(Cr)的净化效果不明显,而且水体中的pH上升11.05%~11.61%,EC值增加21.12%~22%,DO增加3.82~21.77倍。芡实作为一种乡土水生植物,对沿淮地区富营养化河流具有显著的净化潜力。 展开更多
关键词 芡实 富营养化河流 水体净化 综合分析 氨氮去除 总磷去除 溶解氧增加 酸碱度变化 可溶性盐含量变化
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Prediction of Salt Tolerance in Rice (Oryza Sativa) Based on Shoot Ion Content under Non-Stressed Conditions
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作者 Souleymane Bado Brian Peter Forster +7 位作者 Roman Padilla-Alvarez Christian Resch Alessandro Migliori Yacouba Diawara Milko Jaksic Abdelbagi Mukhtar Ali Ghanim Stephen Nielen Margit Laimer 《材料科学与工程(中英文A版)》 2016年第1期1-16,共16页
关键词 水稻基因型 耐盐性 ORYZA 离子含量 应激 非遗传因素 多变量统计分析 元素含量
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盐分胁迫对基质栽培番茄养分吸收与生长的影响
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作者 林琼 何淽琦 朱鑫 《绿色科技》 2024年第9期75-78,191,共5页
探究了盐分胁迫对基质栽培番茄养分吸收及生长的影响,以期为番茄基质栽培营养液管理提供参考。以“德尔5号”番茄为试材,营养液设置0 mmol/L(CK)、30 mmol/L(低浓度)、60 mmol/L(中浓度)、120 mmol/L(高浓度)4个不同NaCl浓度处理,比较不... 探究了盐分胁迫对基质栽培番茄养分吸收及生长的影响,以期为番茄基质栽培营养液管理提供参考。以“德尔5号”番茄为试材,营养液设置0 mmol/L(CK)、30 mmol/L(低浓度)、60 mmol/L(中浓度)、120 mmol/L(高浓度)4个不同NaCl浓度处理,比较不同NaCl浓度处理营养液对番茄不同部位叶片氮、磷、钾、钙、镁、钠等矿质元素含量及生物量、产量的影响。结果表明:①NaCl胁迫番茄叶片K含量显著降低,Na含量显著升高,中浓度以上胁迫番茄下部叶Mg含量显著下降。试验条件下,NaCl胁迫对番茄叶片N、P、Ca含量无显著影响;②中低浓度NaCl胁迫对番茄生长影响较小,高浓度NaCl胁迫抑制番茄生长,生物量及产量均显著降低。综上,营养液含中低浓度NaCl(60 mmol/L)对番茄生长及产量影响较小,为预防番茄K、Mg缺乏,缓解盐分胁迫,可适当提高营养液配方中K、Ca、Mg比例。 展开更多
关键词 番茄 盐分胁迫 NACL 养分含量
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基于尺寸效应的夯土水盐运移分布特征研究
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作者 朱晶 裴强强 +1 位作者 郭青林 张博 《岩土力学》 EI CAS CSCD 北大核心 2024年第5期1481-1494,共14页
水盐循环作用是夯土遗址渐进式破坏的主要影响因素之一。为了研究尺寸对夯土水盐运移分布特征的影响规律,制备5组含盐量为0.3%、边长为50、100、200、500、900 mm立方体夯土试样,并将其置于温度为10~27℃、相对湿度为20%~50%的室内环境... 水盐循环作用是夯土遗址渐进式破坏的主要影响因素之一。为了研究尺寸对夯土水盐运移分布特征的影响规律,制备5组含盐量为0.3%、边长为50、100、200、500、900 mm立方体夯土试样,并将其置于温度为10~27℃、相对湿度为20%~50%的室内环境进行自然失水试验。在失水周期内,通过钻孔取样,检测夯土试样表层至内部土体的含水率及含盐量,并分析不同尺寸夯土试样水盐运移特征及尺寸效应。试验结果表明:夯土试样的失水周期及表层土体盐分富集量随尺寸的增大而增大,失水速率随尺寸的增大而减小。不同尺寸夯土试样的失水周期分为快速失水、缓慢失水、稳定失水3个阶段,水盐运移活动主要发生在快速失水阶段。失水过程中,盐分随水分向试样表层运移,表层土体盐分含量增加,内部土体盐分含量降低,盐分集中富集在表层土体上。该研究可以为土遗址室内小块体试验、模拟足尺试验和野外观测试验研究提供理论支撑。 展开更多
关键词 夯土 水盐运移 失水 含盐量 含水率 周期 尺寸效应
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土壤调理剂对滨海盐碱地土壤盐分含量及夏玉米产量的影响
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作者 韩笑晨 张贵芹 +9 位作者 王亚辉 任昊 王洪章 刘国利 林佃旭 王子强 张吉旺 赵斌 任佰朝 刘鹏 《作物学报》 CAS CSCD 北大核心 2024年第7期1776-1786,共11页
研究不同类型土壤调理剂对滨海盐碱地夏玉米田0~10 cm、10~20 cm、20~30 cm和30~40 cm土层土壤盐分含量、玉米根系形态和籽粒产量的影响,为滨海盐碱地区夏玉米田适宜土壤调理剂的选用提供理论依据。试验于2022—2023年夏玉米季在山东省... 研究不同类型土壤调理剂对滨海盐碱地夏玉米田0~10 cm、10~20 cm、20~30 cm和30~40 cm土层土壤盐分含量、玉米根系形态和籽粒产量的影响,为滨海盐碱地区夏玉米田适宜土壤调理剂的选用提供理论依据。试验于2022—2023年夏玉米季在山东省滨州市滨海盐碱型农田进行。采用完全随机区组设计,以不施土壤调理剂为对照(CK),设置3种不同类型的土壤调理剂,分别为硅钙钾镁型调理剂(T1)、硅钙钾镁沸石型调理剂(T2)和硅钙钾镁聚丙烯酰胺(PAM)型调理剂(T3)。研究不同类型土壤调理剂对0~40 cm土层土壤盐分含量、玉米根系形态、叶面积指数、地上部干物质积累量、氮素积累量及籽粒产量的调控效应。结果表明,与CK相比,玉米拔节期(V6)T1、T3处理20~30 cm土层土壤总盐含量和Na+含量分别降低6.88%和23.00%、28.82%和17.44%,土壤HCO3–含量分别升高10.97%、5.66%;吐丝期(R1)T2处理10~40 cm土层土壤总盐含量、Na+含量分别平均降低9.07%、14.11%,土壤HCO3–含量平均升高21.35%。土壤总盐含量降低有利于根系和地上部生长。与CK相比,吐丝期T1、T2和T3处理0~40 cm土层玉米单株平均根系长度分别提高17.56%、74.83%和33.53%;T2和T3处理单株平均根系表面积分别提高33.35%和27.44%,单株平均根系干重分别提高14.58%和11.93%。与CK相比,T1、T2和T3处理显著提高了玉米的叶面积指数,植株地上部干物质积累量以及氮素积累量,最终提高了夏玉米产量。2022年T1、T2和T3处理籽粒产量分别提高3.81%、8.22%和4.72%;2023年分别提高8.08%、18.88%和15.95%。综合分析可知,本试验条件下硅钙钾镁沸石型调理剂可有效降低玉米吐丝期土壤盐分含量,减轻盐分胁迫,促进玉米根系生长和对氮素的吸收,增加地上部氮素积累量和干物质积累量,显著增加籽粒产量,是滨海盐碱地降低盐碱胁迫促进夏玉米生长的最佳土壤调理剂类型。 展开更多
关键词 滨海盐碱地 土壤调理剂 土壤盐分含量 根系 籽粒产量
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基于Landsat 8的节水改造背景下盐渍化土壤含盐量反演
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作者 刘伟 史海滨 +3 位作者 苗庆丰 刘晓志 段倢 王禹森 《农业机械学报》 EI CAS CSCD 北大核心 2024年第1期294-304,共11页
为探明沈乌灌域节水改造后因渠道衬砌、引排水量减少引起的土壤含盐量时空分布特征及变化规律,采用区域土壤信息定点监测,结合经典统计学、空间插值以及机器学习建模反演等技术手段,利用Landsat 8卫星获取光谱数据,通过对实测土壤含盐... 为探明沈乌灌域节水改造后因渠道衬砌、引排水量减少引起的土壤含盐量时空分布特征及变化规律,采用区域土壤信息定点监测,结合经典统计学、空间插值以及机器学习建模反演等技术手段,利用Landsat 8卫星获取光谱数据,通过对实测土壤含盐量、光谱指数及波段反射率进行处理,运用Adaboost回归、BP神经网络回归、梯度提升树回归、KNN回归、决策树回归、随机森林回归方法构建了沈乌灌域土壤含盐量空间反演模型。采用最优反演模型对沈乌灌域土壤含盐量空间分布特征进行了遥感反演。结果表明:通过全变量单一回归法筛选出相关系数大于0.55的9个光谱因子,使用SPSS PRO软件构建6种机器学习反演模型,对比6种反演模型精度,验证集决定系数R2由大到小依次为随机森林回归、梯度提升树回归、Adaboost回归、KNN回归、决策树回归、BP神经网络回归。其中随机森林回归模型的拟合精度最佳,训练集与验证集的决定系数R2分别为0.834和0.86,说明随机森林回归模型的反演效果较好。反演结果表明:节水改造后非盐渍土面积增加391.7 km^(2),占灌域总面积的21%,中度盐渍土面积、重度盐渍土面积、盐土面积分别减少95.61、63.37、45.7 km^(2),分别占灌域总面积的5%、3%、2%。综上所述,节水改造工程完成后,沈乌灌域土壤盐渍化程度减轻,作物生长安全区面积增加,但由于渠道衬砌以及引排水量减少,土壤盐分淋洗效果减弱,土壤盐分在灌域内部运移,整体土壤环境得到改善,局部地区出现盐分聚集。 展开更多
关键词 节水改造 土壤含盐量 遥感反演 Landsat 8
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高分子活性剂改良盐渍土力学特性及机理研究
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作者 车文越 刘瑾 +2 位作者 郝社锋 卜凡 任静华 《建筑材料学报》 EI CAS CSCD 北大核心 2024年第5期446-453,共8页
基于三轴剪切试验与可溶盐含量测试,探究高分子活性剂掺量与养护时间对硫酸型盐渍土力学性能与可溶盐含量的影响,揭示土体微观特性及其改良机理.结果表明:CLI型高分子活性剂的掺入能有效提升硫酸型盐渍土的力学强度和抗变形能力,其最佳... 基于三轴剪切试验与可溶盐含量测试,探究高分子活性剂掺量与养护时间对硫酸型盐渍土力学性能与可溶盐含量的影响,揭示土体微观特性及其改良机理.结果表明:CLI型高分子活性剂的掺入能有效提升硫酸型盐渍土的力学强度和抗变形能力,其最佳掺量为8%;活性剂与盐渍土发生置换反应,从而增强盐渍土的保水性能,有效降低盐渍土的可溶盐含量,CLI型高分子活性剂掺量越大,改良效果越好;养护时间达到7 d时,盐渍土的可溶盐含量趋于稳定. 展开更多
关键词 硫酸型盐渍土 高分子活性剂 力学性能 可溶盐含量 机理分析
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