Sustainable greenhouse systems

Greenhouse systems improve growing conditions of vegetable, fruit and ornamental crops. Greenhouse coverage protects plants from adverse atmospheric agents and, together with suitable equipment, influences and ultimately modifies the crop microclimate, thus lengthening the market availability of the products, improving their quality and allowing higher yields. Greenhouse production has a higher return per unit area than crops grown in the open field, but it requires the use of large amounts of energy to operate the equipment on one hand and generates huge quantities of wastes to be disposed of on the other hand. Protected cultivation can be environmentally unfriendly, especially in areas with a large concentration of greenhouses. Therefore, the steady worldwide increase in the area covered by greenhouses has generated the need for developing sustainable protected horticulture. Sustainable greenhouse horticulture can be achieved by means of different cultivation techniques, adequate equipment management and innovative materials aimed to reduce agro-chemicals and energy use, water consumption and waste generation. The achievement of optimal greenhouse microclimate conditions, the application of integrated pest management strategies and the use of innovative closed-loop fertigation systems with water recycling result in a significant reduction of plant diseases-and, consequently, of agro-chemicals use-and in a decrease in the consumption of both water and fertilisers as well as in the contamination of water bodies associated with nutrient leaching. Optimal climate control and reduction of energy consumption can be obtained by using suitable active and passive systems including proper control strategies for equipment and the use of innovative covering materials. Renewable energy sources and technologies, such as solar thermal and photovoltaic systems, can be used to reduce fossil fuel consumption for climate control. Waste generation mainly concerns the use of materials such as covering and mulching plastic films that must be disposed of at the end of their life; the introduction of innovative biodegradable materials can reduce this kind of waste, improving crop sustainability. The chapter presents the design concepts of greenhouse sustainable systems based on the application of innovative covering materials, microclimate control strategies, renewable energy sources and the use of leading technologies. In addition, it considers fertigation and integrated pest management strategies that may contribute to sustainable operations. © 2010 Nova Science Publishers, Inc. All rights reserved