جستجوی مقالات مرتبط با کلیدواژه "structural equation modeling" در نشریات گروه "آب و خاک"

Supplying fresh water is one of the issues of humanity today and among the concerns of the United Nations and the FAO. Due to sudden changes in freshwater supply and demand patterns in the current world, its supply management is followed as a challenge. The purpose of this research is to design a conceptual model and structuring of fresh water supply chain using the combined approach of soft systems methodology and structural equation modeling. By conducting an open interview and posing a single and comprehensive question to 20 active experts and experts in a snowball manner, and then the role of researchers in system placement, the model will be presented. Qualitative model extraction was done with the SSM method and then in the quantitative part, the factors involved and identified by this method were measured in the form of hypothesis generation by researchers and their testing in PLS-SMART software, the findings showed that if the fresh water supply chain is considered as a system, The input and supply of this high-quality water system, rain and flood; disruption in the processing and analysis of this stakeholder tapping system; control for culturalization as an influencing and modulating factor of this system; Multiple weather, policy instability, natural disasters as environmental and political factors; The policy of order and quantity consumption and quality control to shape the cultural control; disturbing demand and output in this logistics distribution system are water wastage and prediction of wrong consumption and tax evasion and finally the optimal achievements of the water footprint identification model, analysis of water sustainability issues and water shortage control.

Infrastructure factors provide the main basis for agricultural production and activity under conditions of limited water resources and are considered as strategic requirement for improving this sector. The aim of this research was recognition, determination of importance and level of effectiveness, and investigating the relation of infrastructural components and indicators in improving agricultural water productivity. The method used for this research was field surveying type in which, after documentary and library studies, a self-made questionnaire was developed for interview with professionals and practitioners to gather their opinion on the importance level of different indicators using a Likert Scale, followed by analysis of questions and assumptions. The research indicated the relation and effectiveness level of variables by means of structural equation modeling and Smart PLS software. According to the obtained results, emphasis of infrastructures were on the side of agricultural water supply, while lack of demand oriented approach, process, systematic, and holistic view were among the main problems of the infrastructures. Also, components such as “downstream instrumentation of the fields and wells with water measurement devices and controlling irrigation water” and “share of downstream farms equipped with systems for lowering water consumption out of the total cultivated area” were among the most effective factors. It was shown that by taking other variables as constant, agricultural water infrastructures have been effective (about 87.6%) on improvement of agricultural water productivity, and there is a positive and meaningful relation between each one of the components and related indicators.

Shortage of water is one of the main factors limiting development of agricultural activities. This has led to the fact that farm management and productivity of agricultural water need full participation of farmers. Therefore, the purpose of this study was to analyze the factors affecting barriers and facilitators in adoption/development of new irrigation systems by farmers. The statistical population of this study included 70 experts of the departments of Agriculture Jihad whose viewpoints were collected and analyzed. Data was collected by using a questionnaire as research tool and SPSS and Lisrel software were used for analysis. To determine the reliability of the questionnaire, alpha coefficient was used by R software, which amounted to 91 percent, reflecting the reliability of data in similar conditions. In order to identify the factors affecting barriers and facilitators in development of new irrigation systems, factor analysis was used. The results of analysis in development barriers section led to identification of five barriers that included farmers awareness, technical problems, administrative costs, government policy, and technical knowledge. These barriers could explain about 69 percent of variations of adopting new irrigation systems. Identified facilitators included satisfaction of progressive farmers, clear comparative advantages, and monitoring and institutional partners. These facilitators could explain about 40 percent of variations about adoption of new irrigation systems. Also, in order to identify direct and indirect relationships between identified barriers and facilitators, Structural Equation Modeling (SEMs) was used. Results of this section showed that farmer awareness (β= 0.87), administrative costs (β= 0.67), clear benefits (β= 0.54) barriers had a direct impact on the development of new irrigation systems. Also, other results of this study showed that there was an indirect and weak relationship between administrative costs, farmers’ interests, and farmers’ awareness in development of new irrigation systems. According to the results, none of the identified facilitators had any significant effect on the adoption of new irrigation systems by farmers.

Drought is an unavoidable natural disaster in dry and arid regions of the world. Studies indicate that Iran with its geographical and climatic characteristics is poor in water resources. Moreover, it is estimated that in 2025, Iran should increase the water resources by 112% in order to maintain status quo. Therefore, the occurrence of drought is more prevalent in the future. This implies a real challenge for researchers to study how to manage farms during the onset of drought. Inappropriate management strategies result in loss of resources, which in turn leads to more destructive impacts of drought, consequently leading to more droughts in future. The purpose of this survey study was to identify factors influencing drought management among farmers in Fars province, Iran. A multistage stratified random sampling technique was used to select a representative sample of farmers who has experienced drought in recent years. A total of 258 farmers were interviewed using a questionnaire. A panel of experts verified face validity. A pilot study was used to assess the reliability of the measuring instrument. Cluster analysis and Structural Equation Modeling were used for data analysis. Results indicated that farmers with different social, economical, and technical characteristics chose different management strategies when coping with drought conditions. Despite farmers' efforts to manage drought, they face harsh consequences. These consequences include economic losses and degradation of farming environment. It is therefore recommended that policy makers who are involved in drought management programs learn more about farmers' drought mitigation techniques and make further attempts to increase the efficiency and effectiveness of techniques used by farmers.