Determination of susceptible areas to water erosion in the Hervi watershed

The cover crop on the soil surface is a fundamental practice for the establishment of soil and water conservation systems.The Santa Fé System consists of the inclusion of forage species in the grain production system, mainly by intercropping. The objective of the study was to evaluate the effect of cultivation of single maize and maize in consortium with U. brizantha cv. marandu, in runoff and qualityof runoffusing a rainfall simulator.The experiment was carried out at the School Farm of the IF Goiano Campus Iporá in a Quartzipsament, in a Brazilian Savanna region.The following land coverwere evaluated: uncoveredsoil, single hybrid corn and SantaFé System. For the determination of the runoff volume and the runoff quality, three tests were performed in each treatment, using a pendulum rainfall simulator built at the IF Goiano Campus Iporá. In each test, the total volume of runoffwas counted and every five minutes samples were collected to characterize the runoffquality, in which turbidity, pH and electrical conductivity were analyzed.Water losses were reduced by 82% and turbidity by 96% in the Santa Fé system, compared to uncoveredsoil.The Santa Fé System showed better performance with less runoff volume and better quality of runoff when turbidity was evaluated, which demonstrates its high potential in minimizing soil water erosion.

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A DETERMINATION OF AREA OF POTENTIAL EROSION BY GEOGRAPHIC INFORMATION SYSTEMS

Journal of Environmental Engineering and Landscape Management ◽

10.3846/16486897.2007.9636922 ◽

2007 ◽

Vol 15 (3) ◽

pp. 144-152 ◽

Cited By ~ 9

Author(s):

Peter Šurda ◽

Ivan Šimonides ◽

Jaroslav Antal

Keyword(s):

Information Systems ◽

Geographic Information Systems ◽

Soil Loss ◽

Agricultural Land ◽

Slovak Republic ◽

Water Erosion ◽

Geographic Information ◽

Limit Values ◽

Area Of Interest

Accelerated water erosion is the major problem of agricultural soils all over the world and also in the Slovak Republic. Accelerated erosion occurs in 55 % of agricultural land. It belongs to physical degradation of fertile land, and the whole process is irreversible. Therefore, it is very important to localize the presence of accelerated erosion and apply the basic principles of soil erosion control. Geographic information systems (GIS) are an effective tool for various environmental analyses, so it can also be succesfully used for determination of potential erosion intensity. The aim of this work was to create a map of domain areas that describes potential water erosion. As an area of interest the cadastral territory of Topolcianky in the Slovak Republic was selected. For this purpose the GIS software Arcview from ESRI was used. Water erosion process was modelled by universal soil loss equation (USLE) which computes an average annual soil loss. The limit values of acceptable intensity of soil loss are defined in the Collection of Laws of the Slovak Republic (Act No 220/2004 Coll). The final result of this work is a map that divides the domain area according to potential annual soil loss into several categories. In this case the domain area was divided into four categories. The first category, named slightly threatened soil, had 620,05 ha of agricultural land (77,48 per cent of the total agricultural land of domain area). The second category, called averagely threatened soil, had 106,56 (13,32 per cent of the total agricultural land). The third category (intensively threatened soil) had 70,91 ha (8,86 per cent of the total agricultural land) and finally the fourth category (very intensively threatened soil) had 2,74 ha (0,34 per cent of the total agricultural land).

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The determination of the relationships between physical and chemical properties of soils to water erosion and crust strengths in Menemen Plain Soils, Turkey

African Journal of Agricultural Research ◽

10.5897/ajar11.737 ◽

2012 ◽

Vol 7 (2) ◽

Author(s):

Gökçen YÖNTER

Keyword(s):

Chemical Properties ◽

Water Erosion ◽

Physical And Chemical Properties ◽

Chemical Properties Of Soils ◽

Physical And Chemical ◽

And Chemical Properties

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Comparison of methods for determination of soil erodibility factor K

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun200553050197 ◽

2005 ◽

Vol 53 (5) ◽

pp. 197-206 ◽

Cited By ~ 2

Author(s):

Jana Dufková ◽

František Toman ◽

Milada Šťastná

Keyword(s):

Soil Loss ◽

Water Erosion ◽

Soil Erodibility ◽

Comparison Of Methods ◽

Universal Equation ◽

K Factor ◽

Soil Erodibility Factor ◽

Soil Units ◽

Soil Unit

The comparison of values of the soil erodibility factor  K (which is used in the universal equation for soil loss calculation), that were determined according to the main soil units and values of the K factor determined on the base of texture analysis, has found differences in soil texture in the range of the same main soil unit. The need of the laboratory analyses follows from the comparative analyses for the determination of K factor that is also necessary for determination of threat of soil by water erosion or for the projection of erosion control. The values of K factor that was specified according to the soil ecological units could be possible to take as orientational ones.

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Methodology update for determination of the erosion coefficient(Z)

Glasnik srpskog geografskog drustva ◽

10.2298/gsgd1201011t ◽

2012 ◽

Vol 92 (1) ◽

pp. 11-26 ◽

Cited By ~ 2

Author(s):

Radislav Tosic ◽

Slavoljub Dragicevic

Keyword(s):

Information Technologies ◽

Modern Society ◽

Water Erosion ◽

Project Work ◽

Erosion Coefficient ◽

The Mean ◽

The Republic ◽

High Degree ◽

Empirical Methodology

The research and mapping the intensity of mechanical water erosion that have begun with the empirical methodology of S. Gavrilovic during the mid-twentieth century last, by various intensity, until the present time. A many decades work on the research of these issues pointed to some shortcomings of the existing methodology, and thus the need for its innovation. In this sense, R. Lazarevic made certain adjustments of the empirical methodology of S. Gavrilovic by changing the tables for determination of the coefficients ?, X and Y, that is, the tables for determining the mean erosion coefficient (Z). The main objective of this paper is to update the existing methodology for determining the erosion coefficient (Z) with the empirical methodology of S. Gavrilovic and amendments made by R. Lazarevic (1985), but also with better adjustments to the information technologies and the needs of modern society. The proposed procedure, that is, the model to determine the erosion coefficient (Z) in this paper is the result of ten years of scientific research and project work in mapping the intensity of mechanical water erosion and its modeling using various models of erosion in the Republic of Srpska and Serbia. By analyzing the correlation of results obtained by regression models and results obtained during the mapping of erosion on the territory of the Republic of Srpska, a high degree of correlation (R? = 0.9963) was established, which is essentially a good assessment of the proposed models.

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Galactic orbits of stars

Symposium - International Astronomical Union ◽

10.1017/s0074180900105340 ◽

1966 ◽

Vol 25 ◽

pp. 93-97

Author(s):

Richard Woolley

Keyword(s):

Globular Cluster ◽

Potential Field ◽

High Velocity ◽

Velocity Vector ◽

Variable Stars ◽

The Sun ◽

Proper Motions ◽

Rr Lyrae ◽

The Galaxy

It is now possible to determine proper motions of high-velocity objects in such a way as to obtain with some accuracy the velocity vector relevant to the Sun. If a potential field of the Galaxy is assumed, one can compute an actual orbit. A determination of the velocity of the globular clusterωCentauri has recently been completed at Greenwich, and it is found that the orbit is strongly retrograde in the Galaxy. Similar calculations may be made, though with less certainty, in the case of RR Lyrae variable stars.

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Distance to SN 1987A and the LMC

Symposium - International Astronomical Union ◽

10.1017/s0074180900118959 ◽

1999 ◽

Vol 190 ◽

pp. 549-554

Author(s):

Nino Panagia

Keyword(s):

Angular Size ◽

Large Magellanic Cloud ◽

Magellanic Cloud ◽

Light Curves ◽

Distance Modulus ◽

Absolute Size ◽

Sn 1987A

Using the new reductions of the IUE light curves by Sonneborn et al. (1997) and an extensive set of HST images of SN 1987A we have repeated and improved Panagia et al. (1991) analysis to obtain a better determination of the distance to the supernova. In this way we have derived an absolute size of the ringRabs= (6.23 ± 0.08) x 1017cm and an angular sizeR″ = 808 ± 17 mas, which give a distance to the supernovad(SN1987A) = 51.4 ± 1.2 kpc and a distance modulusm–M(SN1987A) = 18.55 ± 0.05. Allowing for a displacement of SN 1987A position relative to the LMC center, the distance to the barycenter of the Large Magellanic Cloud is also estimated to bed(LMC) = 52.0±1.3 kpc, which corresponds to a distance modulus ofm–M(LMC) = 18.58±0.05.

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International determination of the total motion of the pole

Symposium - International Astronomical Union ◽

10.1017/s0074180900177824 ◽

1961 ◽

Vol 13 ◽

pp. 29-41

Author(s):

Wm. Markowitz

Keyword(s):

Secular Motion ◽

The Future

A symposium on the future of the International Latitude Service (I. L. S.) is to be held in Helsinki in July 1960. My report for the symposium consists of two parts. Part I, denoded (Mk I) was published [1] earlier in 1960 under the title “Latitude and Longitude, and the Secular Motion of the Pole”. Part II is the present paper, denoded (Mk II).

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Time and Latitude in South Africa

International Astronomical Union Colloquium ◽

10.1017/s0252921100026816 ◽

1972 ◽

Vol 1 ◽

pp. 27-38

Author(s):

J. Hers

Keyword(s):

South Africa ◽

Cape Town ◽

Astronomical Observations ◽

Royal Observatory ◽

The Republic ◽

Astronomical Determination ◽

Limited Accuracy ◽

Better Than

In South Africa the modern outlook towards time may be said to have started in 1948. Both the two major observatories, The Royal Observatory in Cape Town and the Union Observatory (now known as the Republic Observatory) in Johannesburg had, of course, been involved in the astronomical determination of time almost from their inception, and the Johannesburg Observatory has been responsible for the official time of South Africa since 1908. However the pendulum clocks then in use could not be relied on to provide an accuracy better than about 1/10 second, which was of the same order as that of the astronomical observations. It is doubtful if much use was made of even this limited accuracy outside the two observatories, and although there may – occasionally have been a demand for more accurate time, it was certainly not voiced.

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