Journal of Saffron Research, University of Birjand
Saffron is a perennial plant and is a native product of the eastern part of Iran, with its bulb capable of growing for 5 to 7 years, which can lead to changes in soil properties over the long term. Therefore, a study was conducted to examine some physical and chemical properties of soil in saffron fields aged one to seven years. To this end, 50 hectares of saffron fields in the Gazik region (located in South Khorasan Province) were selected. The experiment was designed as a completely randomized design with one treatment (years of cultivation) at six levels (1, 2, 3, 4, 5, and 7 years) and eight replications in the year 1386 (2007). Soil samples were collected from a depth of 0 to 30 centimeters from one to seven-year-old fields. The percentage of organic matter, particulate organic matter, mean weight diameter of soil aggregates, soil moisture at field capacity and permanent wilting point, total nitrogen percentage, available phosphorus content, and the micronutrient elements iron, copper, zinc, and manganese were measured.
The results showed that the percentage of organic matter in the soil increased with the age of the fields. The year of cultivation did not have a significant effect on the amount of particulate organic matter. The mean weight diameter of soil aggregates, field capacity moisture, and permanent wilting point increased in the seven-year-old fields compared to the one-year-old fields. Total nitrogen and available phosphorus also increased with the age of the fields. Additionally, in the seven-year-old fields, the availability of micronutrient elements iron, copper, zinc, and manganese significantly increased compared to the one to three-year-old fields.
