Ridge–furrow rainfall harvesting system helps to improve stability, benefits and precipitation utilization efficiency of maize production in Loess Plateau region of China

Abstract

The ridge–furrow rainfall harvesting (RFRH) system is considered an effective strategy for improving crop productivity and it has been adopted increasingly in the arid and semiarid rainfed agricultural areas of China. However, how RFRH performs at improving the crop productivity and the economic benefits of long-term implementation are not known in different counties and conditions in the Loess Plateau region. Therefore, RFRH and traditional planting method (CK) experiments were carried out by us under five different hydrothermal conditions in the Loess Plateau for many years. The denitrification–decomposition (DNDC) model was corrected and verified by field test data. Then, the performance of RFRH and CK in time (from 1990 to 2019, three test points) and space (387 counties, 112,000 km−2 grain crop planting area) was simulated. The results showed that from 1990 to 2019, the maize yield was 9200–11,395 kg ha–1 under RFRH and 1433–11,326 kg ha–1 under CK. The interannual variation in the maize yield was small under RFRH and it significantly improved the maize yield in dry years (87.0% higher than CK). In addition, RFRH effectively stabilized and improved the maize biomass (increased by 26.9%), harvest index (increased by 24.3%), and economic benefits (increased by 63.4%). In the whole Loess Plateau region, compared with CK, the average grain yield under RFRH increased by 86% and the average net income increased by 133%. The capacity of RFRH to increase the economic benefits in the Loess Plateau regions followed the order of: northwest region > northeast region > southwest region > southeast region. RFRH can improve and stabilize the maize yield, but also enhance the economic benefits of maize production in this region. Therefore, RFRH can be used as an important technique for coping with years when different amounts of precipitation occur in the Loess Plateau region, but especially in the northwest where the precipitation is limited.