三峡库区森林土壤优先流染色特征   总被引：7，自引：2，他引：5  

张财宝  刘目兴  王文德  张海林  黄建武  杜文正 《水土保持学报》2012,26(2):80-84

森林土壤优先流在涵养水源和调节径流过程中起着重要作用,林地优先流特征研究对分析森林土壤水分入渗特征和探讨森林对流域水文过程的调节机制具有重要意义。使用染色示踪法在三峡库区不同垂直带内进行森林土壤优先流染色试验,研究不同山地森林土壤的染色特征。结果表明:不同森林土壤的表层(0-10cm)染色比例和染色剂入渗深度差异较大,土壤染色垂直变化趋势也不相同。中山常绿和落叶阔叶混交林表层土壤染色比例最高,染色剂入渗最浅,土壤染色比例随深度变化呈连续下降趋势。中山常绿针叶林表层土壤染色比例和染色剂入渗深度在不同样地间存在着变异,土壤染色垂直分异特征存在一定的差异。低山常绿针叶林表层土壤染色比例最低,染色剂入渗最深,土壤染色比例随深度变化呈波动下降趋势。不同森林土壤中优先流路径数量和分布不同是导致染色特征存在差异的主要原因,而森林土壤中的根系、裂隙以及土壤物理性质等都会影响到优先流的形成。  相似文献   

弓形虫直接凝集试验改良法的研究   总被引：4，自引：1，他引：3  

张述义  郑思民 《中国兽医寄生虫病》1994,2(2):11-13

用弓形虫直接凝集试验改良法（ＭＤＡＴ）、染色试验（ＤＴ）和两种间接荧光抗体试验（ＩＦＡ）平行检测了国内外的７１份人血清，结果表明ＭＤＡＴ与其它试验符合率达９１．８～９６．０％；同时显示有较高的敏感性和特异性。用ＷＨＯ国际生物标准化实验室的标准血清定量测得ＭＤＡＴ的灵敏度为０．０９ＩＵ／ｍｌ，接近于改良前方法和ＤＴ的灵敏度，高于国外同类试剂盒的灵敏度。作者认为本ＭＤＡＴ具有在基层单位推广和应用的潜在价值。  相似文献   

Quantification of the effects of soil compaction on water flow using dye tracers and image analysis   总被引：2，自引：0，他引：2  

S.J. Mooney  W. Nipattasuk 《Soil Use and Management》2003,19(4):356-363

Abstract. Soil compaction has long been considered to be a problem in arable land, primarily because it causes damage to soil structure, which can lead to serious reduction in crop yields. However, few studies have sought to investigate the effects of soil compaction on the water transport regime of modified soil pore systems. We attempted to quantify the effects of soil compaction on the initiation of preferential flow by using dye tracers and image analysis. A laboratory methodology involving rainfall simulation enabled us to quantitatively evaluate differences in the mechanisms of water flow between two soil types at several degrees of compaction. The results suggested significant differences in the types of water flow pathways between clay loams and sandy loams at different extents of compaction. In the sandy loam, it was concluded that a high degree of compaction led to an increased likelihood of preferential flow, whereas a more uniform movement of soil water occurred at less compaction. By contrast, preferential routing of soil water was recorded in the clay loam, except at the highest measured compaction. The results indicate that the visual techniques of dye tracing and image analysis could enable improved understanding of flow pathways of soil water associated with soil compaction.  相似文献   

Dissipation of triclopyr herbicide applied in Lake Minnetonka,MN concurrently with Rhodamine WT dye     

Fox AM  Haller WT  Getsinger KD  Petty DG 《Pest management science》2002,58(7):677-686

Fluorescent dye was applied concurrently with triclopyr in two 6.5-ha treatment plots in Lake Minnetonka, MN for data collection to support full aquatic registration of this herbicide. The herbicide and dye mixture was applied by airboat to Phelps Bay with weighted, trailing hoses to maximize uniform distribution of these materials in the water column. A surface application was made to the Carsons Bay plot to attain theoretical triclopyr and dye concentrations of 2500 and 10 micrograms litre-1, respectively. Water samples collected at various times following application showed very little movement of the herbicide and dye out of the Carsons Bay plot. Triclopyr residues moved to a greater extent out of the Phelps Bay plot. The dye was easily tracked in real-time using field fluorometers, which allowed new sampling stations to be established to monitor this movement. Dye concentrations were strongly correlated to herbicide concentrations (r2 = 0.97 in both plots) but were less predictive of the triclopyr metabolite 3,5,6-trichloropyridinol (TCP; r2 = 0.82 in Phelps and r2 = 0.73 in Carsons), probably due to its differential metabolism and degradation. The inert dye can be used to compare the dissipation of herbicide residues by dilution versus microbial or other breakdown processes. Vertical sampling of dye in the water column showed that surface applications of aquatic herbicides can delay uniform mixing in the water column by several days. Although the dye aided the tracking of residues outside the treatment areas, predetermined sampling times and stations were still needed if very low concentrations of herbicide were to be detected at times and stations where the dye had been diluted below its limit of detection.  相似文献   

速生杨木单板染色阻燃性能研究     

王晓倩  于志明  张扬  王芳 《西北林学院学报》2016,31(5):276-280

为研究酸性染料和无机阻燃剂同步处理对杨木单板性能的影响,用酸性大红3R染料和BL-阻燃剂对杨木进行染色阻燃,采用单因素法,探讨染色阻燃工艺参数对单板上染率、色差、载药率和氧指数的影响。结果表明:随浸渍温度的升高,上染率和色差均呈先增大后减小趋势,载药率和氧指数增大;随浸渍时间的延长,上染率和色差呈增大趋势,载药率和氧指数先迅速后缓慢增加;随酸性大红3R浓度的增加,上染率和色差先增大后减小,载药率和氧指数呈先缓慢后迅速减小趋势;阻燃剂的添加促进了单板上染率,随阻燃剂浓度的增加上染率呈先增大后逐渐减小的趋势,色差逐渐增大,载药率和氧指数都增大。  相似文献   

4种林木年轮水分输导模式研究   总被引：1，自引：1，他引：0  

刘盛  宋彩民  李国伟 《北京林业大学学报》2011,33(2):14-18

以年轮为基本研究单位,对选择的4个树种(银中杨、蒙古栎、红松、落叶松)采用水分输导轨迹的染色标记和定量滴定方法,研究了林木的水分输导模式.结果表明:树干中不同年轮间的水分输送能力存在显著差异,新生年轮(近3年)的水分输送能力明显较强,从输送面积看均超过了总输送面积的2/3.在年轮与年轮之间没有发现水分的横向输导现象;水...  相似文献   

酸性染料比色测定玛咖总生物碱含量的条件考察     

杜广香  浦跃武 《广东农业科学》2011,38(5):142-144

以乌头碱为对照品,采用酸性染料比色法测定了玛咖总生物碱的含量,并对其显色条件进行选择.结果表明,玛咖生物碱含量测定的最佳条件为:乌头碱对照品在40-320μg范围内,pH4.0氢氧化钠一邻苯二甲酸氢钾缓冲液6 mL及其配置的0.5%溴甲酚绿显色剂2 mL,显色50 min,412 nm处检测.此法测得玛咖粉末中总生物碱含量约为4.65%.且该法操作简便、精密度高、稳定性好、具良好的可重复性.  相似文献   

应用改进的平板检测法快速筛选解钾菌   总被引：2，自引：1，他引：1  

M. V. S. RAJAWAT  S. SINGH  S. P. TYAGI  A. K. SAXENA 《土壤圈》2016,26(5):768-773

The utility of microorganisms for solubilizing the unavailable forms of potassium(K) from soil has led to renewed interest in fabrication of rapid and sensitive plate assays for their isolation and screening. The present study developed a modified plate assay and compared it with previously reported methods for the isolation and screening of K-solubilizing bacteria. The newly developed plate assay is based on improved visualization of halo zone formation around the colonies on agar plates, through inclusion of an acid-base indicator dye, bromothymol blue(BTB), to modify the previously reported Aleksandrov medium. The halo zone exhibited a significant correlation(R = 0.939) with K released in liquid medium. The visualization of potential K solubilizers was improved using this method, which would help in detection of weak/non-acid producers based on secretion of organic acids in the medium. Organic acids in plate diffuse radially and form halo zones in response to reaction with the acid-base indicator dye BTB. Furthermore, K solubilization on plates with this method can be observed within 48–72 h, against the incubation time of 4–5 d needed in the earlier method. Therefore, the newly developed protocol for the plate assay was time saving, more sensitive, and beneficial in comparison to the previously reported Aleksandrov plate assay.  相似文献   

耐铜菌株4bs的鉴定及其对染料脱色的效果     

孙海琼  汪春蕾 《湖南农业大学学报(自然科学版)》2016,42(4):403-408

从土壤中筛选出1株具有较高漆酶活性的菌株,经分子生物学方法鉴定,该菌株为芽孢杆菌属细菌,将其命名为Bacillus sp.4bs。菌株4bs的最适生长温度和pH分别为37℃和7.0,其在6%(w/v)Na Cl溶液中能够正常生长,在含有2.0 mmol/L Cu~(2+)的培养基中仍生长旺盛。以丁香醛连氮为底物,菌株4bs的芽孢漆酶活性为35.66U/g(干重),其芽孢漆酶最适反应温度为80℃,最适反应pH值为6.8;0.1 mmol/L的半胱氨酸、二硫苏糖醇和叠氮化钠抑制其活性,10 mmol/L的Na~+, K~+, Cu~(2+)和Li~+能够增强其活性。在pH 6.8的体系中,菌株4bs芽孢漆酶对结晶紫和茜素红在6 h内的脱色率分别为83.57%和77.16%;加入乙酰丁香酮(Ace)作介体时,对靛红的脱色率由52.73%提高到94.98%,对活性黑5的脱色率由19.01%提高到90.10%。  相似文献   

比色法测定鸡蛋中苏丹红残留的研究   总被引：6，自引：0，他引：6  

朱云芬  陈宽维  葛庆联  高玉时 《江西农业学报》2010,22(5):125-127

通过试验研究,建立了鸡蛋中苏丹红Ⅰ～Ⅳ残留的快速测定方法(比色法):将鲜鸡蛋样品用乙腈反复提取,分别在491(苏丹红Ⅰ)、513(苏丹红Ⅱ)、348(苏丹红Ⅲ)、478(苏丹红Ⅳ)nm下用紫外分光光度计测定吸光度,再根据所建立的苏丹红Ⅰ～Ⅳ的标准回归方程,即可计算出样品中苏丹红的残留量。本方法的回收率为88.5%～92.3%,相对标准偏差0.8%～2.6%,最低检测限为1μg/mL。  相似文献