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The paper aims to study of the parameters of the maize yield trend parameters in the territory of 10 administrative regions of Polissya and Forest-steppe zones of Ukraine and to find out the influence of landscape diversity factors on them. State Statistics Service of Ukraine provided the maize yields data by the administrative districts. The calculations of the yield model parameters were performed in R Project for Statistical Computing. Landscape diversity was estimated based on the Shannon index. Spatial images are made using ArcGIS 10.1. It was found that during the study period maize yield dynamics described by a sigmoid curve (log-logistic model). The parameters of the yield model are the following indicators: lower limit of yield; upper limit of yield; slope that showing the rate of change in yield over time and ED50the time it takes to achieve half of the maximum yield level. The lowest yields during the study period were observed in the early and mid-1990s. Areas with higher value of minimum yields are characterized by a more rapid increase in yield over time. The spatial variation map of the ED50 is, in turn, a complete reflection of the yield rate map. The upper limit of productivity, at which at a given level of agrotechnology, the yield is determined precisely by the biotic potential of the territory occur in the current time period. Analyzing the map of the location of different environmental protected objects and the average distance to them, we concluded that the northern regions of Ukraine is characterized by the highest density of the Nature Preserve Fund (NPF) objects. Regression analysis revealed a statistically significant correlation between the upper limit of maize yield (maximum productivity) and the Shannon index. There is also a correlation between the distance to the environmental objects and the upper yield limit, which is described by the second-order equation. Therefore, there is an optimum value of landscape and ecological diversity, under which the maize production potential reaches the highest level.