Spatial variation in iodine content with relation to soil physicochemical properties in lower Himalayan region

Jawad Ali; Muhammad Mohiuddin; Xinfeng Wang; Zahid Hussain; Muhammad Irshad; Munir Zia; Rashid Pervez; Mohammad K Okla; Shakeel Ahmad

doi:10.1016/j.envres.2024.118569

Spatial variation in iodine content with relation to soil physicochemical properties in lower Himalayan region

Environ Res. 2024 Mar 1;251(Pt 1):118569. doi: 10.1016/j.envres.2024.118569. Online ahead of print.

Authors

Jawad Ali¹, Muhammad Mohiuddin², Xinfeng Wang³, Zahid Hussain⁴, Muhammad Irshad⁵, Munir Zia⁶, Rashid Pervez⁷, Mohammad K Okla⁸, Shakeel Ahmad⁹

Affiliations

¹ Environment Research Institute, Shandong University, Qingdao, 266237, China. Electronic address: jawadhvn@gmail.com.
² Department of Environmental Sciences, Kohsar University Murree, Murree 47150, Pakistan.
³ Environment Research Institute, Shandong University, Qingdao, 266237, China. Electronic address: xinfengwang@sdu.edu.cn.
⁴ Department of Development Studies, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, Pakistan.
⁵ Department of Environmental Sciences, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, Pakistan.
⁶ Research and Development Coordinator, Fauji Fertilizer Company Ltd., Rawalpindi, Punjab, Pakistan.
⁷ College of Marine Sciences, Shantou University, China.
⁸ Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia.
⁹ School of Environment, Tsinghua University, Beijing, 100084, China.

PMID: 38431069
DOI: 10.1016/j.envres.2024.118569

Abstract

Topography of a place has a significant impact on soil characteristics that ultimately influence soil iodine levels. Lower Himalayan region (LHR) in Pakistan has a wide range of climatic and geological variations. Hence, an investigation was conducted to analyze the iodine concentration and other physicochemical properties of soils in two LHR districts, Haripur and Mansehra. Spatial analysis indicated a decrease in iodine levels in the mountainous regions in comparison to the flat portions of LHR. Soil samples obtained from different locations across Haripur had a stronger affinity for iodine due to variations in solubility and adsorption of iodine to soil clay components, which can be attributed to lower pH, higher organic matter, and a higher cation exchange capacity (CEC). In contrast to the plains of Haripur, elevated locations in the Mansehra district had decreased levels of iodine, along with a higher soil pH and reduced soil organic matter. The soil erosion and depletion of soil micronutrients in the hilly region of Mansehra may be attributed to the unfavorable soil conditions and excessive precipitation. Presence of clay, iron (Fe), and aluminum (Al) in the soil led to a rise in iodine levels. Iodine concentrations exhibited an inverse relationship with soil acidity. Study revealed a direct correlation between soil iodine levels and their cation exchange capacity (CEC) and clay content. This study aims to gather fundamental data for the chosen regions of LHR to address illnesses caused by iodine deficiency.

Keywords: Iodine concentration; Iodine deficiency disorders; Mountainous area; Plain area; Soil properties; Topography.