Evaluation of optimal irrigation scheduling and groundwater recharge at representative sites in the North China Plain with SWAP model and field experiments

Abstract

a b s t r a c tThe application of water saving irrigation is essential to alleviate the rapid depletion of groundwater resources in water crisis areas such as the North China Plain (NCP). The integrated effects of climate, soil and groundwater conditions on water balance and crop response need to be further studied. It is imperative to investigate spatial differences of irrigation scheduling and groundwater recharge within the NCP for regional water management. In this study, three representative sites including Luancheng (LC), Tongzhou (TZ) and Yucheng (YC) with different precipitation, soil and water table conditions were selected. The SWAP model was established at each site to compare optimal irrigation scheduling and groundwater recharge of the winter wheat-summer maize double cropping system under different hydrological years. Largest optimal irrigation amount and additional irrigation at the winter-dormancy stage of wheat were required for the TZ site in each hydrological year. The optimal irrigation scheduling was almost same at the three sites for summer maize, except that no irrigation was needed at filling stage in dry year at the YC site. The average annual groundwater recharge under optimal irrigation was in the order of YC (108.4 mm), TZ (63.8 mm) and LC (0.4 mm). Furthermore, the groundwater recharge occurred throughout the double cropping seasons in YC, but it occurred only in summer maize season at the LC and TZ sites. The net irrigation amount of the optimal irrigation scheduling was reduced by 51.2%, 24.9% and 77.2% compared to reference practice at the LC, TZ and YC sites, respectively. The amount of groundwater recharge depended on the local precipitation and irrigation, while water table depth and soil texture mainly influenced the delay time of groundwater recharge relative to the water input events.

Modelling root water uptake under deficit irrigation and rewetting in Northwest China

“…Crop variables (LAI, crop height, and rooting depth) were specified as a function of the crop development stage. The development stage was assumed to be linear with a growth period from emergence to harvest (0 < development stage < 2) (Ma et al., ). Extinction coefficients for diffuse and direct visible light were used as the model default values, which were 0.60 and 0.75, respectively (Hassanli et al., ; Jiang et al., ).…”

“…SWAP has performed well for simulations of farmland water and heat flow under different soil conditions (Martínez-Ferri, Muriel-Fernández, & Díaz, 2013). The SWAP model has also been used to schedule irrigation (Jiang, Feng, Ma, Huo, & Zhang, 2016;Ma, Feng, & Song, 2015;Rallo, Agnese, Minacapilli, & Provenzano, 2012) and estimate crop yield at the field and regional scale (de Jong van Lier, Wendroth, & van Dam, 2015;Hassanli, Ebrahimian, Mohammadi, Rahimi, & Shokouhi, 2016;Mokhtari, Noory, & Vazifedoust, 2018). Some research has shown that SWAP simulation results are superior to other models (Bonfante et al, 2010;Eitzinger et al, 2004;Hassanli et al, 2016).…”

Impact of capillary rise and recirculation on simulated crop yields

“…Precipitation, soil texture and water table depth jointly affected the amount of groundwater recharge and time lag between water input and groundwater recharge (Ma et al, 2015). We quantified some of these issues, but several items remain, such as the impact of rooting depth on crop yield and transpiration.…”

Has water-saving irrigation recovered groundwater in the Hebei Province plains of China?

“…However, due to the many factors that affect the groundwater regime, it is difficult to quantify the contribution of each factor to changes in the groundwater table (Ma et al, 2016). To date, studies have discussed the influence of irrigation development on groundwater depletion (Hu, Delgado, Zhang, & Ma, 2005;Lv et al, 2013;Ma et al, 2016;Yang, Watanabe, Sakura, Tang, & Seiji, 2002) and the impact of implementing water-saving irrigation on halting the fall of the groundwater table or even raising the groundwater table (Liu et al, 2007;Hu et al, 2010, Ma, Feng, & Song, 2015. Unfortunately, the majority of existing studies have focused only on one irrigation district or several representative sites to explain and quantify the influence, and a regional-scale analysis has not been done.…”