بررسی آزمایشگاهی ﺗﺄثیر زئولیت بر رفتار خاک های شالیزاری منطقه گیلان در مراحل بروز ترک در حالت آبیاری تناوبی

Abstract

Abstract Rice can be cultivated in various soils but soil with heavy texture and low permeability is more appropriate for its growth than other types of soil texture. It’s assumed that existence of zeolite in soil can be effective for moisture retention and avoiding of occurrence of crack in soil. In order to investigation of the effect of zeolite on moisture status and hydraulic properties of Guilan province’s paddy’s soils, zeolite factor was conducted in four levels (0, 8, 16, 24 tons per ha) in five stages of soil moisture (saturation, appearance of capillary crack, final crack, returning from final crack to capillary crack, destruction of crack) in three replications as factorial based on complete randomized block design in a soil texture (Silty clay) as the dominant texture in Guilan area in Iran’s Rice Research Institute. Results showed that moisture in saturation stage did not change much by adding zeolite, while in capillary crack stage, moisture storage has increased to 7% and in final crack stage, it has increased to 17 %. So you see, after a cycle of dry and wet, the amount of moisture and bulk density has not turned back to its primitive amount, also the volume of inflammation in soil’s moistening trend is far lower than the volume of subsidence in soil’s drying trend and the soil has not turned back to its primitive volume. Finally, the effect of zeolite on the volume of consumable water has been significant at five percent statistical level. Keywords: Zeolite, Clinoptilolite, Cracked soil, Water condition, Rice