Soils of these areas have been affected by erosion and scouring that modifies the topography, land leveling and the elimination of bunds for paddy fields , soil fertility losses when upper layer is washed away, deposition of salted sediment, salt infiltration and trash and debris accumulation.
Recovery of the affected areas will require several years in some areas lacking sufficient rainfall for rapid outwash of accumulated salts and will be an additional burden to the local population. Skip to main content. Privacy statement Legal notice Cookies Search.
Once the databases were in the same reference system, we were able to match the spatial information and explore the semantic components of the data. These polygons were displayed on a separate layer. On areas where both maps had information on salinity, the information from the ESDB took priority. Following this method we compiled an updated version of the Saline and Sodic Soils Map. Irrigation with high salt content waters dramatically worsens the problem.
Salt affected soil can be divided into five main groups: Saline soil Solonchak with high amount of water soluble soils. Alkaline soil Solonetz , high alkalinity and high exchangeable sodium percentage ESP. Magnesium soil: high magnesium content in the soil solution.
Gypsiferous soil: strong gypsum or calcium sulphate CaSO4 accumulation. Acid sulphate soil: highly acidic iron or aluminium sulphate accumulation. Salt affected soil often exhibits a white or grey salt crust on the ground. The pH of the soil is around 8. In Europe, the first two groups are the most significant. The factors that determine the accumulation of salt in a soil are as follows: source of salt local weathering, surface and subsurface waters, human activities ; transporting agents accumulating salts from large areas to smaller deposits as well as from thick geological strata to thinner horizons usually water, wind ; limited vertical or horizontal drainage conditions; driving force for movement of solution, usually relief surface runoff , hydraulic gradient groundwater flow , suction capillary transport or concentration gradient diffusion ; negative water balance evapotranspiration greater than precipitation.
Two main types of salt accumulation in soil can be distinguished in Europe: Continental salt accumulation due to intense weathering and arid climate or due to hydro-geological conditions e. While non-saline soils do not affect crops, strongly saline ones are suitable only for salt-tolerant species and halophytes. Thus, salinization reduces ecosystem varieties and threatens their normal conditions to exist. A reduction of flora diversity inevitably causes a reduction of fauna as well by shortening food chains and areas of habitats.
Salinization reduces biodiversity in rivers or fresh-water lakes, shortening aquatic populations solely to salt-tolerant species. Soil salinization effects refer to crop diversity and, correspondingly, food variety as farmers are forced to produce plants that can survive in salty earths.
Soil salinization is a serious problem itself, but it rarely comes alone. Salinity causes continuous wetness of land surface and a lack of cover due to poor plant growing conditions.
These make lands highly prone to erosion. With heavy rainfalls or river flooding, soils cannot cope with high amounts of water flows. Thus, insufficient absorption results in runoffs and floods. Strong water currents ruin constructions, damage farmlands, increase sedimentation, and contaminate aquatic bodies. The best way to deal with soil salinization is not to let it happen.
In case it did, it is important to eradicate the problem — the sooner, the better, before the consequences get too severe. So, soil salinization solutions deal with prevention and management. Soil salinization prevention bases on avoiding excessive salt penetration.
Even though plants require a certain amount of salts to develop, their needs are small compared to the content in salt-affected soils. Here are some typical methods to prevent soil salinization :. As a preventative measure, Crop Monitoring allows tracking the vegetation state in the field and identifying areas with sparse vegetation or bare ground surface. Timely scouting of such zones enables farmers to understand and eradicate the root cause, tackling the issue before it gets too severe.
Crop Monitoring may assist the process of reducing soil salinity. Shallow-rooted plants may not reach subsoil moisture, and extra subsoil moisture may induce salinity. Crop Monitoring provides reports on surface soil moisture and root-zone moisture, facilitating the choice of crops for planting in the exact areas.
Differentiated fertilization thanks to the zoning feature on Crop Monitoring mitigates the risks of salinization due to excessive chemicals application. It assists in applying chemicals in the amounts a separate field area requires: no more, no less. Smart zoning calculates vegetation maps and productivity maps.
Bekle, H. Phillips, and J. The salinity crisis: Landscapes, communities and politics. Crawley: Univ. Beresford, et al. Ghassemi, F. Jakeman, and H.
Salinization of land and water resources: Human causes, extent, management and case studies. Sydney: Univ. Ghassemi, et al. The authors describe salinity problems in thirteen selected countries, including Argentina, Australia, China, Egypt, India, Iran, Pakistan, South Africa, Thailand, and the United States, as well as processes of salinization in land and water resources and management strategies.
Hillel, D. Soil salinity: Historical and contemporary perspectives. Hillel is a paper that discusses historical and contemporary perspectives on soil salinity.
This paper is useful to understand the general nature of salinization through generations. Jacobsen, T. Salt and silt in ancient Mesopotamian agriculture. Science Jacobsen and Adams is a short paper which gives an account of salinization problems in an ancient civilization. Shows that the problem of salinity is not new, and how salinization can destroy an entire civilization. Rengasamy, P. World salinization with emphasis on Australia.
Journal of Experimental Botany — Salinization of farmland and limited fresh water access is threatening global food security and the livelihood of many farmers. As a result, farmlands are becoming more saline, making it difficult for smallholder farmers across the globe to produce food for their family, their cattle and for sale at markets. By using traditional farming practices for irrigation and fertilization, salinity levels have even been seen to increase.
In many places, salt-affected lands become non-arable. In addition to the struggle farmers face, salinization is a serious threat to global food security. According to FAO, , the world population is expected to grow to 9. Picture: Salt-affected soil. As populations increase, so does food demand. But with farmland turning into a wasteland, this is becoming a great challenge.
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