مدیریت ذرت ذخیره شده توسط کنترل AERO در پنج مکان برزیل: یک مطالعه شبیه سازی

A simulation model was used to quantify the effect of the AERO controller on dry matter loss, moisture content, grain temperature and required aeration time for five Brazilian States during one year. The application focused on maize because it is the dominant crop in the regions studied, but the analyses can be applied to other grains and locations as well. Decision making of the AERO controller is based on simulation of the aeration process and on real time data acquisition. It proved to be an effective strategy and showed its significant potential as a non-chemical preventative practice for safe storage

When grains are placed into storage they are exposed to a broad range of complex ecological factors that work against the stored grain manager's objective of maintaining grain quality. Grain temperature is important because it directly affects grain quality, development of pests and dry matter losses (Maier et al., 1996). But the moisture content is also a significant factor since the lower it is, less susceptible grains are to spoilage by insects, mites or fungi (Longstaff, 1994). It is usual practice to implement preventive management, rather than to solve specific storage problems once they have occurred. Aeration is a well-known and proven Integrated Pest Management tool for controlling the quality of stored grain. The two primary objectives of aeration are to maintain uniform temperatures inside the bin and keep temperatures below the limits for insect and fungal development (Navarro and Noyes, 2001). However, this technique remains an underused tool in some situations, particularly in warm climates such as in Brazil. Thus, the development of appropriate control strategies will enable aeration to be more widely and efficiently used in these regions. When ambient aeration is used, it is very important to operate the system during appropriate conditions for efficient storage management. The AERO controller is a promising strategy which was developed with the objectives of maintaining grain quality with minimal energy input, automatically adjusting its set points according to different climates and storage systems based on real time data acquisition and on simulations of the aeration process (Lopes, 2006). As simulation of a grain storage ecosystem is less expensive and a time-saving alternative to field research, in this study simulations were carried out to evaluate the effectiveness of AERO control strategy for maintaining safe storage of maize in five Brazilian locations.

Results presented in this work confirm that the quality of the maize stored in different Brazilian regions can be efficiently controlled with the AERO strategy for long periods assuring safe storage conditions. The simulation model can also be applied to other grains and aeration systems. The software AERO is available for download at www.evandro.eng/agroinformatica. With this free version of the software it is possible to simulate different control strategies, including that discussed in this work, with different grain types and aeration systems designs. Also, it is possible to use variable ambient data as input data and simulate hot spots inside the bin.