ВОЗМОЖНОСТИ ИСПОЛЬЗОВАНИЯ СПУТНИКОВЫХ ДАННЫХ ПРИ СЕЛЬСКОХОЗЯЙСТВЕННОМ СТРАХОВАНИИ

Analysis of usage of satellite data in agricultural insurance was conducted. Main peculiarities and ways of potential usage were listed. It was highlighted that satellite data can be successfully used for crop monitoring, risks and damages assessment, as well as for pastures monitoring. The perspectives of usage of UAV images instead of satellite data for small areas were noted.Проведен анализ возможности использования спутниковых данных для страхования посевов. Установлены особенности и основные направления использования спутниковых данных при сель-скохозяйственном страховании. Показано, что спутниковые данные могут быть использованы для мониторинга состояния культур, оценки страховых рисков, оценки потерь урожая, а также для контроля состояния пастбищной растительности. Отмечена перспективность использования при страховании посевов наряду с космическими изображениями данных, получаемых с беспилотных летательных аппаратов

Usage of satellite data for soil mapping: Modern tendencies and problems

The modern specifics of the use of satellite data for soil mapping was analyzed. At present, despite that remote sensing methods have long been developed, the satellite data is still quite rarely used in soil science for compilation of soil maps. Some researchers use satellite color composites as the background as well as a data source for analysis of relief conditions of a territory for soil mapping. Others try to develop methods for automated analysis of satellite images. The use of different methods to a large extent is determined by the scale of maps and geographical features of the research area. In most cases, multispectral data of high and very high spatial resolution are used. Radar satellite imagery and hyperspectral data are used for soil mapping only in some cases. In contrast to previous decades, now more research is aimed on mapping of the individual properties of the surface soil horizon, rather than for compilation of soil maps. This is due to the fact that the properties of the upper soil horizon are not always related to their classification status, which have to be shown on soil maps

Usage of satellite data for soil mapping: Modern tendencies and problems

The modern specifics of the use of satellite data for soil mapping was analyzed. At present, despite that remote sensing methods have long been developed, the satellite data is still quite rarely used in soil science for compilation of soil maps. Some researchers use satellite color composites as the background as well as a data source for analysis of relief conditions of a territory for soil mapping. Others try to develop methods for automated analysis of satellite images. The use of different methods to a large extent is determined by the scale of maps and geographical features of the research area. In most cases, multispectral data of high and very high spatial resolution are used. Radar satellite imagery and hyperspectral data are used for soil mapping only in some cases. In contrast to previous decades, now more research is aimed on mapping of the individual properties of the surface soil horizon, rather than for compilation of soil maps. This is due to the fact that the properties of the upper soil horizon are not always related to their classification status, which have to be shown on soil maps

SATELLITE TECHNOLOGIES FOR SMALL-SCALE LAND MONITORING

Usage of satellite data with a spatial resolution of 1 km and 250 meters does not allow anymore increasing the accuracy of crop monitoring results. Improved accuracy could occur only if there is a minimum 10-year archive of satellite data with a spatial resolution of 10-30 meters. Satellite monitoring of soils can be conducted at given moment only on local level. The main limitation for further development of the methods is lack of data on soil and crop spectral reflectance properties

Study of the optical properties of an exposed soil surface

The optical properties of soils are the basis for mapping them from satellite data. The optical surface properties are affected by both soil and nonsoil factors; according to analysis of variance, the contribution of the latter to the variability of the optical properties is a factor of 2 greater. Moreover, their effect on the spectral reflectivity is more specific. Among the nonsoil factors that are analyzed, the mapping time is most closely associated with the optical properties. The models obtained in the course of regression analysis are characterized by good approximation quality and explain more than 61% of the variability of the given factor. The accuracy of the given models for the parameters developed to evaluate the optical properties is greater than 75%. © 2017 Optical Society of America

GPR Diagnostics of Chernozem Humus Horizon Thickness

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

Assessing the performance of speckle filtering techniques in interpreting soil properties of arable lands using Radarsat-2 data by the example of test fields in Saratov Povolzhye

Radar data have great potential for soil studies. However, their interpretation is complicated due to presence of speckle. Using Saratov Povolzhye as a test region we analyzed the performance of adaptive (Gamma Map, Refined Lee, Frost) and non-adaptive (Median) filtering techniques in speckle suppression, preservation of original information and assessed their influence on the possibility of soil features interpretation using Radarsart-2 data. Gamma Map filter was founded to be more effective in speckle suppression for vertical-horizontal and vertical polarizations regardless of the soil surface conditions at the time of image acquisition. Applying this filter with 5×5 window size allowed modelling of organic matter content and particles 0.05-0.01 mm in size with overall accuracy of over 70% for open soil surface and 60% for covered surface. Lower filtering window size (3×3) appeared to be more suitable for mapping 1-0.25 mm sized particles and slope when soil surface is open. In case of granulometric composition and parent material, the best results for the test region were obtained when applying Refined Lee filter for vertical-horizontal polarization and open surface with overall accuracy of the models of 63-65% of the models. The considered results are applicable only for the studied radar data, acquisition time and test region. At the same time, the findings can be used to organize remote monitoring of properties of soil surface layer of the test fields which is important for land use

Solar-caused fluctuations in earth's magnetic field and statistical wheat (Triticum L., 1753) yield

In the light of the latest scientific achievements the great role played by the geomagnetic processes in a variety of phenomena in the world (in the atmosphere, the biosphere and the social sphere) becomes more and more apparent. It is known that the temporal variation of the geomagnetic field is determined by interplanetary processes, the Earth's rotation, as well as fluctuations in solar activity. In this connection, the data on the phenomena on the Sun and changes in the Earth's magnetic field have been widely used in various fields of science and technology and in solving many applied problems. The impact of artificial magnetic fields on the crop growth was demonstrated in the vast number of scientific publications. However, the effect of fluctuations of the natural Earth's magnetic field caused by the influence of the Sun on the crop yield is still practically unknown. The evaluation of the level of correlation was conducted between solar-caused fluctuations in Earth's magnetic field and statistical wheat yield for countries where the crop is grown. This crop is cultivated in many countries of the world, which allows to include in the analysis regions with different natural and agronomic conditions. Actual information about the wheat yield was obtained from FAO's statistical database FAOSTAT (http://faostat.fao.org/site/339/default.aspx). As an indicator of the global geomagnetic activity Kp index was used. Kp index values were averaged for individual days, months, and years. The average value of the index is rounded to the closest standard value of it. Monthly average Kp values were used to calculate the average values of the index for the period of wheat growth. As a result, a statistically significant correlation between the annual change in the yield of wheat and solar-caused changes of Earth's magnetic field was found. The coefficient of correlation in some countries reaches a sufficiently high value. The highest rates of positive correlation set for Belgium (r = 0.7), Kenya, Mali and North Korea (at r = 0.6 for each country). The negative relationship is most pronounced in Russia (r = -0.8), Ukraine, Moldova, Uzbekistan and Bolivia (r = -0.7 for each). Specificity of the manifestations of the correlation around the world suggests the presence of both direct and indirect (through a change in the meteorological conditions) impact of fluctuations of the geomagnetic field on crop yield. In the case of direct impact, the observed correlation of crop yield with the Kp, index averaged for the growing season, should be expressed more clearly than with Kp index, averaged for the year. Our analysis revealed more countries with a statistically significant correlation in the case of usage of seasonal Kp index. It is often observed the following situation: in the case of a negative correlation of crop yield with the annual value of the Kp value of r increases when using the seasonal Kp index, and for a positive relationship between crop yield and the annual value of the Kp index r in the case of the seasonal index decreases (sometimes up to statistically insignificant values). The latter can be explained by the inertia of the reaction of atmospheric processes on the impact of fluctuations of geomagnetic activity, which is similar to that in relation to the impact of El Niño and La Niña on changes in air temperature and precipitation (R. Stefanski, 1994). A more confident conclusion about the importance of the direct and indirect effects can be apparently obtained by carrying out a similar analysis for other crops, as well as through a more precise allocation of time during the growing season in each year and growing region

Reasons for long-term dynamics of NDVI (MODIS) averaged for arable lands of municipalities of Belgorod region

One of the basic products of the Internet service VEGA is the cartograms of the vegetative index NDVI (MODIS) averaged for arable land of municipalities of Russia, updated weekly. The article presents the results of analysis of its long-term dynamics for the period of 2001−2016 for the municipalities of Belgorod Region. The main causes of the observed dynamics are analyzed. It was found that the most significant factors are the changes in crops acreage and the climatic conditions of the growing season. The date of the first NDVI value at the start of the season correlates well with air temperature data. But the trend of this indicator for the period of research (2001−2017) on the territory of the region is not revealed. An indistinct 5−7 years periodicity of local minima and maximums of this indicator is observed. Dynamics of crops acreage has stronger effect on the date of seasonal NDVI maximum than trends of weather conditions (which act towards the onset of an earlier peak in the growing season). It leads, albeit to a weak, but increasingly later NDVI seasonal peak date in the second half of the analyzed period. The main factor of the dynamics of the magnitude of the seasonal NDVI maximum in Belgorod Region is dynamics of the cropping rotations, the combination of crop yields and acreage. The received data should be taken into account when using the Internet service VEGA for operative monitoring of crops. © 2018 Space Research Institute of the Russian Academy of Sciences. All rights reserved

Study of the optical properties of an exposed soil surface

The optical properties of soils are the basis for mapping them from satellite data. The optical surface properties are affected by both soil and nonsoil factors; according to analysis of variance, the contribution of the latter to the variability of the optical properties is a factor of 2 greater. Moreover, their effect on the spectral reflectivity is more specific. Among the nonsoil factors that are analyzed, the mapping time is most closely associated with the optical properties. The models obtained in the course of regression analysis are characterized by good approximation quality and explain more than 61% of the variability of the given factor. The accuracy of the given models for the parameters developed to evaluate the optical properties is greater than 75%. © 2017 Optical Society of America