No abstract

No abstract

A modified chemical ranking and scoring method entitled the CHEMS (Chemical Hazard Evaluation for Management Strategies) model was used to yield a relative weighted risk for insecticides used in the northern areas of Iran. The CHEMS model uses six toxicity and three exposure potential parameters to measure the overall hazard of a substance. The results suggest that Diazinon (granule [GR] 10%) was ranked as a high spot for release-weighted risk in this study although its relatively low risk score (RS) compared to other insecticides, which is due to its high volume consumption. The highest-priority insecticides for future action (the ones that present the highest weighted risk score [WRS]) would include Fipronil, Thiodicarb and Azinphos-methyl. Cartap identified as a hazardous insecticide regarding aquatic organisms and might threaten the natural aquatic ecosystems in these areas if continually used. Thiodicarb had the highest effect on human health. This study showed that a chemical with low RS but high environmental loading and usage and medium persistence (i.e. Cartap) can pose a low WRS. Results of the CHEMS model in this study could help guide a prospective monitoring study, thereby assisting risk managers with managing more efficiently, resources dedicated to mitigating risks posed by insecticides in the northern parts of Iran.

Introduction: Soil health as one of the main components to achieve sustainable agricultural systems is being adversely affected by agricultural operations such as tillage. Soil health can be quantified using the specific physical, chemical, and biological parameters of the soil via specific quantitative soil quality methods. As a result, studying soil quality and fertility in different land management systems is essential to establish appropriate crop operations to achieve optimal production and sustainable cropping systems. Soil Management Assessment Framework (SMAF) is used as a powerful and reliable tool to assess the effect of different crop management on soil quality and health. This study aims to evaluate and quantify the effect of different tillage methods on soil quality using the SMAF algorithm. Material and methods:The present study was conducted as a field experiment based on a randomized complete block design during two cropping years in 2016-2017 and 2017-2018, in four replications.Experimental treatments included tillage methods (no-tillage, reduced tillage, and no-tillage), and the areas were considered replication. Winter wheat (Triticum aestivum L.) was planted in the first year, followed by winter chickpea (Cicer arietinum L.) in the second year of crop rotation in farmers' fields. Soil sampling from a soil depth of 0-30 cm was taken in two stages, before planting wheat at the beginning and after harvesting chickpeas in the second year. Important soil parameters were measured, including bulk density, phosphorus, potassium, acidity, electrical conductivity, soil organic carbon, carbon, microbial biomass, and microbial biomass nitrogen.