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The research aims to measure the economic efficiency and technological change and the total productivity of resources using the parameter and non-parameter methods, for agricultural companies registered in the Iraqi stock exchange, the number of 6 companies for the period from 2005 to 2017 based on the hypothesis that the  agricultural companies do not achieve economic efficiency and does not control the management of its operations, and It may be technically efficient but the size of its operations is not optimal. From non-parametric methods, the data envelope analysis method was used. Using the DEAP program, the Middle East Company achieved the highest average technical and cost efficiency of 0.62 and 0.58, respectively. The Iraqi seed production company achieved the highest average efficiency of 0.66. Using Al- Malmquist Index, the National Company for Agricultural Production achieved the highest rate of change in the total productivity of resources and the highest change in the technical efficiency respectively 1.97 and 2.28, while the Modern company for agricultural production obtained the highest technological change averaging 1.14. A stochastic frontier analysis (SFA) technique was used; logarithmic TL function was estimated using FRONT software. The maximum likelihood method (ML) shows that the capital was increased by 1%, the value of production of companies will increase by 0.22% because it helps to take advantage of the advanced technology that these companies are supposed to work to localize and support the agricultural sector. The cross-elasticity between labor and capital was 0.67 which indicates the nature of the substitution relationship between the two items, because using the technology reduces the workers. The value of sigma-squared was 0.21.

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Flushing time for tidal rivers and estuaries is of great benefits for those involved in taking appropriate decisions in water resources management. Shatt Al-Arab River is the main and only source of fresh water to Basra City, South of Iraq. Unfortunately, this river is facing an environmental deterioration as a result of presence of many pollution sources. The calculated flushing time of the river helps to estimate the expected time needed to renew the river water. Fresh water fraction method was used to calculate flushing time. The results showed that three factors are responsible for affecting the value of flushing time. These factors are upstream coming flow discharge, phenomenon of tide and lastly the location distance from the estuary. The results also showed that the flushing time of the northern part of the river from Maqal port until the confluence with Karun River are much more than that of southern part. Results also showed that the flushing time for the whole parts of the river was 2.4 months.

The tidal excursion length along the Shatt Al-Arab estuary was estimated based on the mathematical relation proposed by Parsa and Shahidi (2010). The field measurements of water level, bathymetry, and discharges were conducted to fulfill the objective of the study. The results revealed that the tidal excursion length is site-specific and depends on the characteristics of location which include tidal phases, bathymetry, and geometry. However, the results indicated that there are pronounced differences in tidal excursions lengths between the spring and neap tide phases in all studies stations. The spring tide coincided with the maximum tidal excursion lengths in Shatt Al-Arab estuary with 16.537, 16.187, 11.122, and 9.139 km in the estuary mouth, Faw, Siba, and Abo Flous stations respectively. While the neap tidal excursion lengths were 12.298, 9.254, and 7.269 km in Faw, Siba, and Abo Flous stations respectively.