Abstract

The purpose of the present paper is to study the key factors responsible for the unsuccessfulness of under pressure irrigation systems in Ilam Province. The research method is casual-relative which is conducted in the form of a survey research. The statistical society of this study includes 440 exploiters who own farming or garden lands and the credits of agriculture bank are granted to them to execute the rain irrigation systems. The sampling method to conduct the study is proportional stratified sampling. To determine the sample size, Kerjesy and Morgan table is used. According to the data of this table, a statistical sample of 250 persons is chosen. The basic tool used in collecting data of this study is questionnaire. To study the reliability of research tools, 30 persons of rural exploiters who are inhabitants of Ilam Province are chosen by random. According to this, the reliability factor of research tool is calculated 92% by using the Cronbach alpha coefficient. Data analysis and processing was conducted in two levels: Descriptive (central and dispersion tendency) and analytic (Spearman correlation coefficient and multi-variable regression in a step-wise form). Results of this study show that there is a meaningful relationship between variables of: The work of designer company, irresponsibility in giving services after installing, incompatibility of under pressure irrigation systems with agricultural-climatic conditions, low quality and broken equipments, the problem of moving pipes and equipments, high expenses of fixing and changing equipments, turn taking of the water, insufficient times and time of irrigation with the variable of unsuccessfulness of under pressure irrigation systems. Results of regression analysis of effective factors on unsuccessfulness of under pressure irrigation systems using step-wise method show that five factors, including: Moving pipes and equipments, low quality and broken equipments, lack of skill and proficiency in company employees for incorrect designing and installing; high expenses of fixing and changing equipments have totally determined the variance of 75%.

Key words: Under pressure irrigation, unsuccessfulness, farmers.