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Monitoring and assessment of coastal saline soils in southern region (Badin) Pakistan Shabnam RATHORE*, Karl STAHR, Boris VASHEV Institute of Soil Science and Land Evaluation (310), University of Hohenheim, Stuttgart, Germany. *Corresponding author’s e-mail: rathore@uni-hohenheim.de The salt affected soils in the southern region of Badin, Pakistan have been a challenge to agricultural production. In order to understand the nature and extent of these salt affected soils, a salinity study was conducted. Different profiles (0-120cm) were exposed from 16 different locations. The sampling sites were selected in such a way as to cover most of the salt-affected area. The results showed that the main causes of salinity were poor irrigation water management without having a suitable arrangement of drainage. Other causes are seepage from canals and shallow saline ground water table. However, there are several natural saline seeps in the region, which can contribute to salinization. Accumulation of salts was high on the surface soil due to capillary rise during fallow season, which resulted in secondary salinization. High free evaporation of water from the surface aggravated the salinization process. Saline and saline-sodic soils were the major salt-affected soils in the region. Most of these salts are easily soluble. While sodium was in excess in saline-sodic, calcium was in excess in saline soils. Chloride was the dominant anion in salt-affected soils. Ground water depth was shallower during the rainy months (June-August) and its salinity was lower than in dry months. Irrigation water salinity was also low from June to August. Saturated paste extracts are high in chlorides, sulfates, and carbonates in all profiles, ESP and SAR are more than 15 in all these soils studied. The average electrical conductivity (ECe) and pH values were17.2 mmhos/cm and 8.7, respectively. The results are valuable for producing a salinity map to show the areas at risk of salinization and planning the management of salinity. Key words: salt affected soils; saline soil; sodic soil, water table depth. 34
Methodology of the analysis of the maps of soil salinity to judge the dynamics of salinization-desalinization processes Dmitry I. RUKHOVICH*, Polina V. KOROLEVA, Yekaterina V. VIL'CHEVSKAY Natalia V. KALININA, , Svetlana V. RUKHOVICH, Elena B. DOLININA V.V. Dokuchaev Soil Science Institute, Russian Academy of Agricultural Sciences, Pyzhevskiy per. 7/2, Moscow, 119017 Russia *Corresponding author’s e-mail: ruh@agro.geonet.ru Salinization is one of the most dynamic soil properties. Secondary salinization intensifies salt transfer in the soil profiles. In the newly irrigated area of the Golodnaya Steppe (Uzbekistan), the salt status of soils may change from nonsaline to strongly saline and vice versa within a year. Despite such a considerable dynamism of salinization–desalinization processes, traditional methods to assess the dynamics of soil salinity are based on the comparison of two maps of soil salinity developed at different times with an arbitrarily chosen time interval between them. Maps of soil salinity reflect the chemical type and the degree of salinization. Nonsaline, slightly saline, moderately saline, strongly saline, and very strongly saline soils are specified. Nonsaline and slightly saline soils can be grouped in one category. Thus, for the soils with the same chemistry of salinization, four legend units characterize the degree of salinization. If two maps for different years are compared, seven combinations are possible: (1–3) soils, whose salinity has decreased by three, two and one grades, respectively (desalinization of different intensities); (4) soils, whose salinity has not changed; and (4–7) soils, whose salinity has increased by one, two and three grades, respectively (salinization of different intensities). It is supposed that the direction of salinization–desalinization processes in the particular area remains unchanged during the studied time interval. We have developed 7 maps of soil salinity for the Usman Yusupov farm (no. 10) in the Golodnaya Steppe of Uzbekistan for different years from 1983 to 2008 on the basis of aerial and satellite images. Their analysis proved that the extrapolation or interpolation of tendencies for a period exceeding one year is incorrect. Thus, a comparison of the maps for 1983 and 1985 indicates the intense salinization, whereas the maps for 1985 and 1986 indicate the intense desalinization for the same area. If only two maps are compared, the error of the estimate of salinization–desalinization tendencies may be as high as 70–80%. To judge the dynamics of these processes, the following series of the maps is suggested. (1) Maps showing the areas with stable salinization. From year to year, their portion is about 25% for each salinity grade; for the entire period, it is only 2.5% of the territory. (2) The map showing the trend of salinization (slope of the curve approximating distribution of saline soils by years); for the studied farm (80 km 2 ), this map contains more than 50 000 polygons attesting to the high spatial variability of salinization-desalinization processes. (3) The map of salinization-desalinization dynamics characterizes the average amplitude (the dynamics coefficient) of salinizationdesalinization processes. In our case, it was calculated on the basis of five maps for 1983–1989: k = ‏,‏‎5‎‏/(׀e-a׀+׀d-e׀+׀c-d׀+׀b-c׀+׀b‏-׀a‏)‏ where a, b, c, d and e are the degrees of soil salinization at a given point (or on a given plot) in 1983, 1985, 1986, 1988 and 1989, respectively. The map demonstrated that the degree of salinization changes by more than one grade on more than a half of the studied territory. Overall, a set of eight maps is suggested to judge the dynamics of salinization–desalinization processes. Key words: soil salinity mapping, salinization–desalinization dynamics, image analysis 35
Page 1 and 2: IUSS Salinization Conference Septem
Page 3 and 4: 2009 September 21 st Monday. Confer
Page 5 and 6: -KHITROV, Nikolai, Yuri TCHEVERDIN
Page 7 and 8: -14:20 - 14:40 YAMNOVA, Irina A., D
Page 9 and 10: Table of Contents AMEZKETA, E., V.
Page 11 and 12: MATUS, G., O. VALKÓ, P. TÖRÖK, M
Page 13 and 14: Relating remote sensing data to app
Page 15 and 16: Secondary salinization caused by us
Page 17 and 18: Amelioration and land use possibili
Page 19 and 20: Mineralogical composition of the cl
Page 21 and 22: Mapping the risk of soil salinizati
Page 23 and 24: Evaluating the ability of hyper acc
Page 25 and 26: Saline water irrigation effect on s
Page 27 and 28: Salinity control under saline shall
Page 29 and 30: Impact of different salts on the mi
Page 31 and 32: and Na is decreasing up to 6-8% and
Page 33 and 34: Groundwater under salt affected soi
Page 35 and 36: Regeneration and evolution of solon
Page 37 and 38: Exchangeable cations of the meadow-
Page 39 and 40: Diagnosis and control of salinity a
Page 41 and 42: Geological conditions of the salini
Page 43 and 44: Using propagule mimics to model see
Page 45: Soil-plant correlations in native s
Page 49 and 50: Biosaline agriculture for biomass a
Page 51 and 52: Changes of salt minerals of soil su
Page 53 and 54: Application of remote sensing to so
Page 55 and 56: An ecohydrological approach to sali
Page 57 and 58: Soil salinization in the Volga delt

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