Risk assessment and zoning of drought for summer maize in the Huang-Huai-Hai Region Optimization of conservation network system for inter-basin wetland ecosystem in Huang-Huai-Hai Region. Characteristics of production and quality of peanut in Huang-Huai-Hai region Applicability of established drought index in Huang-Huai-Hai region based on actual evapotranspiration. Effects of deep vertically rotary tillage on soil water and water use efficiency in northern China’s Huang-huai-hai Region