Modeling and identification of affective parameters on cadmium’s durability and evaluating cadmium pollution indicators caused by using chemical fertilizers in long term

Abstract

Soil contamination by anthropogenic heavy metals has become a global issue. This study aimed to investigate Cadmium (Cd) concentration, the mobility, and contamination indices of Cd in soils in the Hamadan province, west of Iran. One hundred soil samples from wheat farms and ve samples from control lands were collected to investigate the Cd concentration in soil. Pollution indexes, including Cd mobility, enrichment factor (EF), geoaccumulation index (I geo) , contamination index (CI), and Availability ratio (AR), were investigated. The structural equation model was also used to evaluate effective parameters on cadmium's durability in soil. Results showed that mean values of available phosphorus (P) were 83.65, 129, and 65 (mg kg − 1 ) in three land-use types rainfed, irrigated, and controlled, respectively. The mean values of available Cd were 0.15, 0.18, and 0.08 (mg kg − 1 ) in different land-use types of rainfed, irrigated, and controlled, respectively. The results indicated that the amount of Cd in both forms (available and total) in farms that received fertilizer, especially P fertilizers, was higher than in the controlled land. Other pollution indexes revealed that the study area had been slightly contaminated due to anthropogenic activities. Lime, clay, lead, and OM were identi ed as affective parameters on the durability of cadmium. Finally, the results demonstrated that the mobility rate was high. Cd had a higher mobility potential in soil samples in the rain-fed and irrigated land than in the controlled land, and Cd had a low retention time.

Chemical Fertilizer Reduction Potential Estimation and Fertilization Optimization Strategy Based on a 10-Year Application Summary and Status Questionnaires in a Typical Yellow River Irrigated Area

“…Although fertilizers have been used in this region for increasing or maintaining crop productivity, many fertilizers are lost because of microbial activity and climate effects [23]. The fertilizer losses into the air or water will contaminate the coastal environment and threaten the ecological security of the coastal zone [24]. The average organic matter content was at a low level in the Yellow River Delta, so it needs a greater addition of fertilizer to facilitate more food production [25].…”