جستجوی مقالات مرتبط با کلیدواژه "شوری خاک" در نشریات گروه "محیط زیست"

Salts accumulation in soil is a major threat to agricultural production and ecosystem sustainability. The cost imposed on agricultural productivity due to salinity and sodicity is very high and is expected to increase in the future with the expansion of salt-affected areas. In the last decade, a great focus has been made on the application of biochar in farming systems with the primary aim of organic carbon sequestration in soil and subsequently reducing greenhouse gases emission to air and also reclaim soils, and increasing soil fertility. But these studies often were in non-saline soils and it is needed to study the biochar effect in salt-affected soils.

Due to the lack of research on the role of biochar in salt-affected soils, this paper first provides an overview of the extent and problems of these soils. Then, the researches on the effect of biochar on soil properties, carbon sequestration, and remeduatuib if sakt-affected soils were reviewed and study and research gaps in this field were investigated.

The application of biochar in the soil causes the sequestration of carbon in the soil and reduces the emission of greenhouse gases into the atmosphere. In the salt-affected soils, biochar, as an organic soil amendment, improves the physical, chemical, and biological properties of the soil, thereby mitigating the effects of salt on soil and plants.

Carbon sequestration and improvement of soil quality are the two reported general benefits of biochar application in soil. The results of researches in this field are different depending on the source and method of biochar preparation, soil properties, and experiment conditions. Therefore, various studies are needed to fully understand the mechanisms of biochar effect on the properties of salt-affected soils and their remediation. It is not possible to provide a practical solution by doing some research, but developing scientific findings in this field can guide future policies.

An increase in soil and water salinity is one of the world’s problems that are an obstacle to economic and agricultural development. The Arvand river (Shatt Al-Arab), one of the most critical border rivers, is facing a significant decrease in the quality of water and soil due to the intrusion of salty water from the Persian Gulf, which is considered a severe threat to the region. It is formed from the intersection of the Tigris and Euphrates rivers and finally flows into the Persian Gulf. In the current research, the simulation results determined that in the average inflow conditions of Arvand, the saline front penetrates the river up to 60 km from the downstream and affects the river’s water quality. Then the effect of river water salinity on soil salinity was done from two aspects, soil salinity by direct infiltration from riverbanks and soil salinity by long-term use of river water for irrigation. The results showed that in 188 km from the upstream of the river, up to 242 meters, saline water affects the soil on both sides of the river, and in the south of Abadan, this saline band disappears. The prediction of land salinity by irrigation with river water in steady conditions showed that the average salinity of saturated soil extract in Iran in Al-gasbah and in Iraq south of Faw region reaches 97.3 ppt.

In recent years, due to limited water resources in Malayer plain, irrigation methods are changing from surface to under pressure. The purpose of this study was to investigate changes in soil quality due to changes in irrigation methods. For this purpose, 14 farms and 2 orchards equipped with sprinkler and drip irrigation system were selected and their soil quality changes compared with the corresponding values before implementation were evaluated by Mann-Whitney statistical test. Soil quality parameters included acidity (pH), nitrogen (N), phosphorus (P), organic matter (C), electrical conductivity of solutes (ECe) and potassium (K). The zoning map of the studied quality parameters was also prepared using ArcGIS software before and after the implementation of pressurized irrigation systems. The results showed that the difference between the values of the studied parameters before and after the implementation of pressurized irrigation systems including ECe, pH and C were non-significant at the level of 5% probability and the changes of P, K and N were significant. The results of measuring the qualitative parameters showed an increase in the mean values of pH, N, P and C from 7.72 to 7.80, 0.067 to 0.121 mg/kg, 11.01 to 17.95 mg/kg and 0.68 to 0.80%, respectively, compared with before the implementation of pressurized irrigation systems. However, ECe and K values of field soils decreased from 1.06 to 0.53 dS/m and 255.1 to 156 mg/kg, respectively. The results showed that changing the irrigation method reduced potassium and increased soil phosphorus and nitrogen.

The purpose of this study is to investigate the relationship between trend of soil salinity, land use and climatic factors in the region of Shadegan, Khuzestan.

In this study, using principal component analysis and 54 samples of soil, soil salinity maps were prepared for the years 1990, 2006 and 2015. In the next step, land use maps of the region for the mentioned years have been prepared using satellite images and trend changes are determined. On the other hand, changes in climatic factors (temperature and precipitation) for the period of 1990-2015 were evaluated.

Results showed that, reducing precipitation and increasing temperature caused increasing soil salinity during 25 years and also agricultural land and irrigation by saline water increases the salinity of the soil.

Locating Hoor al-Azim wetland in the western part of the region, although it has fresh, brackish and saline water, it may have negative effects on soil salinity of the area because of using in agriculture irrigation. Finally, it can be concluded that soil salinity of the land might change land use and it can cause desertification in the region.