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91.
Eurasian Soil Science - We analyzed the original and most developed environmental legislation of the Netherlands, Germany, the United States, and Canada, as well as the systems of Finland, the... 相似文献
92.
This work aimed to search for indicators of the thickness of the humus horizon of chernozem soils based on the data of ground-penetrating radar (GPR) surveying. The investigation was carried out on a test site located in Russia’s Tula oblast. The area is dominated by arable podzolized chernozems, including ones eroded to a varying extent. In parallel with GPR profiling in the field, soil was drilled to determine the lower boundary of the humus horizon. Based on the conjugate analysis of GPR profiling data and the field determination of the thickness of the humus horizon, a new indicator was proposed: the coefficient of asymmetry of the modal value of the peak of the spectral density of the first-period reflected GPR pulse obtained at a frequency of 100 MHz. The proposed indicator demonstrates a good statistical relationship with the thickness of the humus horizon of chernozem soils. For the test region, a regression model of this relationship was constructed with a determination coefficient of approximately 0.82. To calculate the thickness of the humus horizon (A+AB), it is suggested to use the lower boundary of the second period of the spectral density of the reflected signal, which correlates well with the actual data. The developed approach can be used to map the thickness of the humus horizon in the chernozem soils of the research region. Theoretically, this approach can be extended to soils of other regions. 相似文献
93.
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95.
I. N. Anisimova V. A. Gavrilova V. T. Rozhkova G. I. Timofeeva M. A. Tikhonova 《Russian Agricultural Sciences》2009,35(6):367-370
The presence of the Rf1 gene (pollen fertility restorer of CMS PET1) in genotypes of most restorer lines is confirmed by molecular and hybridological
analysis methods. Molecular markers of the Rf1 locus are identified for the first time in genotypes of autofertile lines of the collection of the Vavilov All-Russian Research
Institute of Plant Industry (VIR) as well as in genomes of perennial and annual wild species of the genus Helianthus. The possibility of introgression of the fertility restorer gene into the genome of the cultivated sunflower during distant
hybridization is shown. 相似文献
96.
The effect of the parameters and operating regime of an axial rotary threshing device on the quality indices of the technological
process of threshing clover seeds is shown. Their optimal values are determined. 相似文献
97.
The use of High Volume Instrument (HVI) to measure cotton lint characteristics produces high dimensional data. A model which
utilized Kohonen Self Organizing Maps (SOM) to visualize cotton lint HVI data, k-means clustering technique to cluster the
data and Probabilistic Neural Network (PNN) for data classification was designed and tested using Kenyan cotton lint. According
to the model the Kenyan cotton lint can be grouped into four clusters, which were successfully classified by using PNN with
a correlation coefficient (R-value) of 1. 相似文献
98.
I. I. Sudnitsyn 《Eurasian Soil Science》2010,43(12):1418-1419
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100.
A. I. Fokina E. V. Dabakh L. I. Domracheva S. G. Skugoreva E. I. Lyalina T. Ya. Ashikhmina Yu. N. Zykova K. A. Leonova 《Eurasian Soil Science》2018,51(5):550-560
The comprehensive diagnostics of the state of soils in the impact zone of thermal power station (TPS-5) in the city of Kirov was performed on the basis of the soil chemical analyses and the study of biota response to the loads at different organization levels. The chemical analyses attested to a satisfactory state of the soils. However, the use of soil cyanobacteria and bird’s-foot trefoil (Lótus corniculátus) as test objects showed the toxicity of studied soil samples. The toxicity of the samples was judged from the bioindication effects of cyanophytization and melanization of soil microbial complexes. The obtained results demonstrated that at relatively low concentrations of total and mobile heavy metal compounds in the soil samples, their amount released into the tested soil water (1: 4) extract exceeded the limit allowable for normal functioning of living organisms. For the first time, the express cyanobacterial tetrazole-topographic method of biotesting was applied in the geoecological study to estimate the toxicity of the soil samples. The results obtained with the help of traditional and express methods proved to be comparable. The express-method was sufficiently sensitive and efficient. It allowed the determination of the samples' toxicity in five hours, i.e., four to five times faster than the traditional technique. An inverse relationship between the number of viable cells of cyanobacteria (as judged from the inclusion of formazan crystals) and the concentration of lead ions in the tested soil extracts was found. This finding can be considered a prerequisite for further study and application of the express method in the practice of geoecological monitoring. Our study demonstrated the necessity of a comprehensive approach for the assessment of the real ecological state of soils in the investigated impact zone of the thermal power station. 相似文献