Cultivation In Greenhouse

1.1. INTRODUCTION 1.1.1. Cultivation in Greenhouses Protected cultivation in greenhouses is a unique and special form of agriculture and represents an important sector in the agriculture around the world. Greenhouses are a type of indoor production facility which is characterized by transparent covers. The cultivation in greenhouses has many economic and environmental advantages comparing to open field cultivation, such as high productivity, high water use efficiency, high-quality products, out of season production, less danger of the agricultural pests, lower labor costs and more profitability. Greenhouses systems also provide the possibility of controlling and modifying the internal environment by practices or structures, and the

Furthermore, understanding the internal climate and thermal behavior of the greenhouse has a great importance in improving the design of the ventilation and heating or cooling systems. This is in most cases leads to the use of the cooling systems that give satisfactory performance under the most extreme weather

Shading prevents the energy from entering the greenhouse and allows enough solar radiation for crop growth requirements. Shading also has the ability to cut out and diffuse the transmitted solar radiation. Consequently, all these results in improving the variation of the greenhouse microclimate. It means that deploying shading nets at optimum locations may do a positive effect on eliminating the variation of the air temperature and relative humidity in greenhouses, especially during the hot period. This is also essential to be used for the evaporatively cooled greenhouses (cooled by wet pads and extracting fans) due to their negative effects on the air temperature, relative humidity, and CO2 variation along with the greenhouse. Therefore, the main objective of this study is to examine the effect of deploying shading nets at different locations on the uniformity of the microclimate in the fan pad greenhouses.

1.2. RESEARCH OBJECTIVES

This research aims to conduct a comparative study between two identical fan pad greenhouses. One greenhouse is without shading and another greenhouse is shaded at three different locations in order to achieve the following objectives:

(1) Effect of shading configuration on the overall microclimate in fan pad greenhouses.

(2) Examine the behavior