## 1 Introduction  
Maize (_Zea mays_ L.) is the second most important grain crop in China. Inner Mongolia is one of the major maize production regions of China that supports the livelihood of farmers in the region [1]. Maize requires a substantial amount of water during the growth phase but 80% of Inner Mongolia is arid and semi-arid, and water shortage in these areas continues to worsen with global climate change [2]. In addition, increase in the cultivable area is remarkably slow; therefore, the crop production area is unlikely to expand in the region so increasing yield per unit area is the only solution to continually support maize-production dependent households [3]. The improvement of maize yield per unit area primarily depends on the extension and reform of agricultural water saving planting technologies [4]. On the one hand, surface mulching is commonly used because of its notable positive impact on water conservation and yield. There are reports that mulching conservessoil moisture by reducing evaporation and saving 12-84% of the irrigation water [5]. Common surface mulching methods include plastic mulching, straw mulching, organic manure mulching, and biochar mulching [6; 7; 8]. Effective use of crop straw and animal manure is conducive to the intensive management of agricultural resources, which is of practical significance for improving crop cropping systems, developing sustainable biodiversity of agro-ecosystems, and implementing national poverty reduction policies [9]. In addition, crop straw mulching and fully rotten organic manure mulching can improve the topsoil physics and chemistry nature of soil remarkably, without causing environmental pollution [10]. On the other hand, efficient irrigation contributes to increases in yields of crops and in income for the local farmers, providing evidence of the significance of irrigation in the past and for future poverty alleviation in China [11]. Therefore, combining mulching with advance irrigation method (drip/micro irrigation) increase more significantly crop productivity and water use efficiency (WUE), reduce water consumption (ET\({}_{\text{c}}\)) in a region where water shortage is the major factor limiting agricultural sustainability [12; 13; 14]. The potential and configuration of climate resources (light, heat, and water) affect their utilization and ultimately limit the sustainable development of agricultural production [15]. Therefore, investigation of the characteristics of crop climate production potential is essential. The production potential of light and temperature is the main focus of studies in China. Water saving potential refers to the amount of irrigation water that can be saved per unit scale of crops, involving four scales, that is, crop, field, irrigation area, and regional/basin, respectively, and is a major factor affecting agricultural structure [16; 17]. The definition of agricultural water saving potential is mainly based on water efficient methods, various water saving techniques, and management [16; 18]. Previously, many approaches have been adopted to measure water saving potential, including efficient irrigation technology and method, irrigation scheduling improvement [19]. For example, some studies used the water balance method and remote sensing technology to calculate water consumption for obtaining the theoretical water saving potential [20; 21], while many studies utilized crop models, such as DASSAT and WOFOST [22], to simulate the water consumption of crops and water saving ability, generating favorable results. Additionally, economic profit evaluation of agricultural technology has been largely explored in maize, confirming that the water saving irrigation method is significantly better than traditional irrigation technology [23], and no-till and permanently fixed ridge is better than conventional tillage [24].