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Geraizade A.P. Institute of Soil Science and Agrochemistry, Baku, Azerbaijan ABSTRACT Today with the help of the space shooting the huge quantity of the information about a soil cover is received. The utilization all this information for the purposes of soil science frequently it happens difficultly. The difficulties are connected mainly that the dependences of reflective properties of soil from its various characteristics are insufficiently investigated. The results of the given work are directed on excluding these lacks at decipering of remote materials. The simultaneously received results can add a databank about the soil characteristics. CONCLUSION For investigated soils the models of change of optical parameters on a structure are made. Is established, that each ground has the spectral curve of distribution of optical parameters. All dependences are expressed by analytical expressions. The received result is offered for use in soil science and agriculture etc. Methods of ground measurement of plant environment parameters in account on the vast territory frequently is given by doubtful results and are connected to significant quantity of casual deviations from their real status. It concerns as the characteristic of ground and plant cover. Therefore today are solved set of various tasks on reception of the information by a remote way containing the total data on many characteristics of environment. Such information is rational for a rating of ground resources, rating of soil degradation degree, of ground solinity degree, of agricultural crops status, and also at mapping of grounds and vegetative cover. The analysis of set of the published works shows, that most of informative parameters at remote sensing of environment investigations are the spectral factors of reflection and its physical essence displaying result of interaction of coming light flows with researched ground objects. Though a significant material on study of spectral factors of soil reflection now is saved, however many questions still are not solved, concerning techniques of spectrometer researches of soil and other natural objects. It is connected that the influencing factors depend on set of interdependent parameters of ground. All this in turn creates difficulties at the formal description of properties and status of soil. The spectrometer researches include as a direct task - reception and data processing about the spectral reflective characteristics of ground, and return task - recognition and definition of various parameters of research object. For a present stage of application of remote methods characteristic the accumulation of significant quantity of the primary information and rather insignificant quantity of the interpreted material is. In this connection on the foreground the problem of the decision of return tasks, and also problem of automation of interpretation of the data of remote sounding enters. Thus the difficulties consist in an establishment of a correct ratio between the taken information and attributes of the object of the image. Soil submitting the general laws of interaction of light and substance has the specificity. The formation of soil optical properties depends first of all on chemical components, from humidity, mechanical components, and also at supervision in a natural status and from height of the Sun above horizon. From chemical components the reflective ability investigated soils basically was influenced of humus substance, by soluble oxides of iron, salts, silicon acid, carbonate, sulphites and etc. In the given work the results of researches of optical properties of various types are resulted soils, formed on various parent breed. The distinctions of the optical characteristics both on a profile of soil and depending on their types are established. Within the limits of each type of soil the dependences of the optical characteristics of soil from the influencing factors are revealed. The surface of a soil cover concerns to casual and non-uniform surfaces and represents set of elements with the certain geometry and distinguished optical properties of each element. The models of the optical characteristics of a soil-plant system are depending on the physical-chemical properties of soil and biometric parameters of plants. At drawing up of such models should be taken into account both casual deviations of separate elements, and characteristic features of these elements. It can be reached on the basis of realization of field and laboratory researches of the optical characteristics of objects. In the first case the casual deviations of separate elements of research object, in second - only characteristic features of these elements should be taken into account. The laboratory research of the spectrometric characteristics allows to create bank of spectral factors of reflection including all basic variety of physico-chemical properties of soil. The offered material can be used as at interpretation of the data received by remote methods, and at realization of classification researches of soil.  Soils used in agricultural manufacture, differ by significant diversity of physico-chemical parameters, and also are exposed also to seasonal change. All this should be taken into account at selection of soil samples for laboratory researches of the optical characteristics of soil, that it was possible to take into account all variety of the influencing factors. Samples are necessary for taking up to presowing cultivation, after postfeeding cultivation, after realization of various agrotechnics processing, after harvest a crop etc. All these factors have the raised variability and result in significant variations of reflective properties of researched objects. Therefore the spectrophotometric information should be taken in view of all influencing factors. Only by such way it is possible to raise stability of the spectrophotometric information on object and, hence, to raise reliability of the received items of information about its properties and status. To minimize mistakes brought in by the influencing factors it is necessary to investigate action of each of them on reflective properties of objects. The spectral factors of reflection of natural objects characterize as well distribution of coming on a surface soil solar radiation, thermal balance of a surface, and also speed and direction of various processes proceeding in ground. The characteristics of separate investigated soils are resulted below. To them concern the Chernozems irrigated. These soils characterizes by an originality of distribution of spectral reflection curve on a profile. As a whole change on size of integrated factor of reflection in limits from 22.1 up to 36.8 % (Table 1). These soils contain in the top horizon about 6.4 % of organic substance, factor of which reflection very low. Same horizon contains 4.73 % carbonate . With depth the quantity is increased up to 28 %, and the quantity of organic substance, accordingly, decreases. The contents of physical clay changes in small limits and, naturally, can not appreciablly participate in formation of factor of reflection on a profile these soil. In this case major factors determining spectral factors of reflection are the contents of organic substances and carbonates. Characteristic feature these soil is the sharp increase of a curve of reflection in red area of a spectrum of light. Three versions of Yermic Cambisols further were investigated. First are Yermic Cambisols irrigated, the second version was chosen in mountain region, third version is the meadow Yermic Cambisols. The change of spectral curve reflection of irrigated Yermic Cambisols on a profile a little bit more e complex, than at Vertic Chernozems Cultivated . The top horizon has these soils has the smooth course of spectral factors of reflection, which size varies in limits from 20 up to 34 %. The following two horizons are characterized by several extreme points on a spectral curve of reflection. Extremums meet at lengths of electromagnetic waves about 500 - 600 nm and 610 - 680 nm. The spectral curve reflections of horizons 67 - 86 cm and 86 - 120 cm differ among themselves only in the field of 400 - 470 nm. In the whole value of factors of reflection varies within the limits of 20 -45 %. The integrated factors on a soil profile change within the limits of 26.0-36.7 %. The contents of organic substance on a soil profile changes within the limits of 2.63-0.6 %. The spectral factors of reflection of Yermic Cambisols on a profile change in an interval 19-42 %. With depth the difference between sizes of factors of reflection of nearby horizons smooths out. The curve reflections on a profile of soil settle down with the certain law. The contents of humus on a profile gradually decreases from 4.17 %, the contents of carbonate were increased on a profile up to size 29.4 %. Integrated factor of reflection changes in limits from 25.7 up to 40.1 % on a profile of soil (Table 1). The character of change of spectral curves in case of Yermic Cambisols Irrigated is even more complex. In this case curves received for different genetic horizons are crossed among themselves. It concerns first of all to horizons 28-50 cm and 50-70 cm, which spectral curves are crossed in the field of 520 nm. The humus horizon these soils stretchs. The contents of humus in the top horizon makes 4.23 %, and on depth 1 m makes size 1.04 %. On spectral curve reflection in dark blue area of a spectrum the minimal values of brightness are appreciable. At transition from dark blue area to green, the brightness of soil grows a little. The greatest size of brightness meets in the field of red waves. The spectral curve of reflection these soils in an average part of a profile of soil sharply grow. It is connected that in an average part of a structure the contents of carbonate high (more than 13 %). In other horizons the contents of carbonate is distributed in regular intervals within the limits of 8.20 - 8.90 %. The spectral curve reflections of Eutric Calsisols Irrigated have wavy character on all profile. Though factor of reflection these soils on a profile changes over a wide range of 27- 60 %, however integrated factors these soils on a profile change rather in a narrow interval 33.7 - 43.5 %. Irrigated meadow soil in comparison with above given sopils have the low contents of humus. These soils have high reflective ability. One of the reasons of such high reflective ability these soils is the high content of carbonates and low contents of humus. The quantity of carbonates on a profiles of soil is increased with depth from 7.96 % to 33.19 % . Thus we see, that all considered here of soils differ as on character of change of spectral curve reflection, and on size of integrated factor of reflection (Table 1). All these differences require realization of the comparative analysis of spectral curve reflection and classical characteristics of soils. Only by such way it is possible to receive the answer to a question: what parameter of ground is the reason of occurrence on a curve concrete extreme point?, also it becomes natural by a key at decipher of remote sending materials. REFERENCES Geraizade A.P. (1999). The dependence of reflection coefficient of soil horizons. In: Proceeding of the Fith Baku International Congress "Energy, Ecology, Economy". Baku. 553 - 556. Geraizade A.P. (1990). Microphotometric analyse of moisture measuring on remote materials. In: Aerokosmic methods in Soil Science and its agricultural application. Moscow, "Nauka", 183-189. P. Kronberg. (1985). Fenderkundung der Erde. Ferdinand Enke Verlag Stuttgart, 350 p. |