Seralar, üretim sezonunda birden fazla ürün elde edilmesi ve üretim sürecinin kontrol altında gerçekleştirilerek verim kayıplarının azaltılması açısından gıda arzına önemli katkı sağlayan tarım sistemleridir. Seralarda birim alandan daha yüksek verim almak için özellikleri ve yapıları itibariyle amaca uygun planlanmalıdır. Tarım işletmelerinde seraların planlanmasında en önemli ölçüt yatırım maliyetidir. Bu doğrultuda çalışma kapsamında tiplerine ve teknolojik özelliklerine göre seraların yatırım analizleri, üretilen ürünlerin verimlilikleri ve işletmelerin karlılıkları karşılaştırılmıştır. Çalışmada, Mersin ilinde sebze üretimi yapan 99 adet plastik, 86 adet cam ve 5 adet topraksız sera işletmelerinde anket yapılmıştır. Anket yoluyla elde edilen verilerde; net kar domates üretilen plastik sera işletmelerinde 9.814,15 TL/da, topraksız sera işletmelerinde 109.532,91 TL/da, biber üretilen plastik sera işletmelerinde 5.522,14 TL/da, hıyar üretilen cam sera işletmelerinde 10.460,53 TL/ da belirlenmiştir. Sera tiplerine göre 3,93 yıl ile topraksız sera işletmelerinde yatırımın geri ödeme süresinin daha kısa olduğu ve 6,68 yıl ile plastik serada domates yetiştiriciliğinin takip ettiği tespit edilmiştir. Dolayısıyla net bugünkü değer domates yetiştiriciliği yapılan plastik ve topraksız seralarda pozitif olup bu yatırımların kârlı olduğunu göstermektedir. Benzer şekilde fayda masraf oranı topraksız domates seralarında 2,05 ve plastik domates seralarında 1,13 hesaplanmıştır. Bu nedenle söz konusu iki sera tipinde ve ürünlerinde projenin geliri yatırımından daha fazla olduğu için karlılık yüksektir.

This study was conducted to assess the structural and environmental conditions and potential problems of under-cover production systems of Çarşamba town, which constitute about 87,81% of under-cover production potential of Samsun Province through comprehensive literature search and to develop possible solutions towards these problems. Selected facilities were analyzed for their structural characteristics, production techniques, technology use, environmental conditions through surveys, drawings, observations and photographs. Present findings revealed that all of the family type under-cover production systems are composed of individual (single) constructions. Facility owners had quite low level of education and under-cover production systems constituted a significant place in their economic statuses. Under-cover production systems were mostly lack of technology because of financial burdens and unplanned production activities. Ventilation, heating and cooling systems, playing a significant role in control of environmental conditions, were mostly insufficient and relevant design criteria were not mostly taken into consideration. With this study, potential problems were identified, structural and environmental requirements of under-cover production systems were determined, and recommendations were provided to producers accordingly.

Ventilation is one of the methods used to obtain the biological optimal point of environmental factors needed for the plants in greenhouses. In the greenhouses, air change coefficient must be more than 50 h-1 in order to supply effective air ventilation. Temperature differences like air change coefficient can be regarded as a criterion to determine efficiency of ventilation in the greenhouses. In this study, the temperature values were calculated by using energy balance and Bernoulli equation at different ventilation opening ratios (AV/AG) depending on climatic properties in the Mediterranean region (Antalya). If was found that, based on temperature and radiation values of Antalya province, 20% ventilation opening rate is sufficient in the roof area. A temperature difference (∆T) of 1K can be achieved with a 50% shading of radiation and a 20% ventilation opening in June in the Mediterranean region. However, additional cooling is necessary in the greenhouses around noon hours because outdoor temperature is greater than 30°C.

In Mediterranean climate region, during certain times of the year the daily average temperature decreases under 12°C. In such conditions, greenhouse heating is essential to be able to get the high quality yield that is expected from greenhouses. The cost of heating varies from 20% to 60% of the total costs depending on the climate of the region, size, type and hardware of the greenhouse and type of plant grown in the greenhouse. The heat requirement in greenhouses is calculated based on the rudiments defined by DIN 4701 standards. However, the real temperature in greenhouses is higher than the outside temperatures used in calculations. For this reason, the heat requirement in greenhouses should be calculated by taking temperature increases that are caused by ventilation temperature and heat storage capability into consideration. In this study, the heat energy need of Antalya which is located in Mediterranean region is assessed according to its climate conditions. In the calculations, the different hardware structures are considered and the level of energy that can be saved is calculated. As a result of the calculations, depending on the month of the year, 12% to 29% difference is observed between energy requirement calculations based on the indoor temperature increases and energy requirement calculations based on outside temperature values.

In Mediterranean climate region, during certain times of the year the daily average temperature decreases under 12°C. In such conditions, greenhouse heating is essential to be able to get the high quality yield that is expected from greenhouses. The cost of heating varies from 20% to 60% of the total costs depending on the climate of the region, size, type and hardware of the greenhouse and type of plant grown in the greenhouse. The heat requirement in greenhouses is calculated based on the rudiments defined by DIN 4701 standards. However, the real temperature in greenhouses is higher than the outside temperatures used in calculations. For this reason, the heat requirement in greenhouses should be calculated by taking temperature increases that are caused by ventilation temperature and heat storage capability into consideration. In this study, the heat energy need of Antalya which is located in Mediterranean region is assessed according to its climate conditions. In the calculations, the different hardware structures are considered and the level of energy that can be saved is calculated. As a result of the calculations, depending on the month of the year, 12% to 29% difference is observed between energy requirement calculations based on the indoor temperature increases and energy requirement calculations based on outside temperature values.

Greenhouse construction projects need to consider local climate characteristics, production type in the greenhouse and materials used for the physical structure and glazing. A major share of commercial greenhouse manufacturers in Turkey produce turnkey greenhouse projects either using by trial and error method or imitating/reproducing greenhouse imported from other countries. Improperly designed projects may result in greenhouses having weak construction or more expensive structures due to using unnecessarily larger profiles which consequently cause a loss the profits for the growers. This study aims to contribute to the improvements and overcome the gaps in practice of greenhouse projects by designing a software for an expert system that utilizes an accurate Project considering them and mandatory buildings standards of Turkish Standardization Institute (TSE). The expert system, named SERASİM, has been developed within the framework of the present MSc. Thesis and enables calculating each part of the construction system of a gable roof glass house according to TSE standards. Besides calculations for statics, dynamics and strength as well estimating the bill of quantity, SERASİM can be utilized to determine the heating requirements and costs for selected locations and crops. SERASİM may also be used as a teaching tool for courses including greenhouse design, protected cultivation and greenhouse acclimatization.