Ridge and furrow mulching improving soil water-temperature condition and increasing potato yield in dry-farming areas of south Ningxia

The plastic-covered ridge and furrow rainwater harvesting combined with mulching cultivation can influence soil water-temperature condition, promote crop growth and development, and increase water use efficiency and yield of crop. This study was investigate the effect of mulching in furrows with different materials and in ridges with plastic film on soil water-temperature condition, potato growth and yield in dry-farming areas of south Ningxia. A field experiment was conducted in 2015 at the Dryland Agricultural Research Station, Changcheng Village, Pengyang County, Ningxia, China (106°45′N, 35°79′E, 1800 m sea level) to determine the effect of different dual-mulching of ridge and furrow cultivation patterns on soil water, soil temperature, growth, yield and water use efficiency of potato. Different furrow treatments were mulched with plastic film (DD), maize straw (DJ), biodegradable film (DS), bast fiber film (DM), liquid film (DY). The treatment of ridge with plastic film and the furrow without mulching was used as the control (CK). The results showed that, the dual-mulching with ridge and furrow adjusted soil temperature, improved moisture availability in the furrow, and the DD and DJ treatments were the most significant. The DD treatment significantly (P<0.05) increased the soil water storage by 4.6%-5.4% compared to CK in the early and middle growing stage of potato. The soil water storage with DJ treatment was the highest in the later growing stage of potato (P<0.05). The DJ treatment had the highest soil water-holding effect compared with CK in whole growing stage of potato, and the average soil water storage under DJ was significantly (P<0.05) higher by 8.4% compare with CK (P<0.05). The DD treatment produced significantly higher soil temperatures (0-25 mm) than CK in the entire stage of potato, while the soil temperature with DJ treatment was significantly lower than CK (P<0.05) in the middle and later growing stage of potato. The average topsoil temperature was significantly increased under DD by 1.2℃ (P<0.05) when compared with CK in the whole growing season of potato, while the soil temperature under the DJ treatment was 1.6℃ (P<0.05) lower than CK. The plant height and stem diameter with DD and DJ treatment was significantly (P<0.05) higher than that of CK in the early growing stage of potato, while the DJ treatment produced the highest plant height and stem diameter (P<0.05) compared to CK in the middle and later growing stage of potato. The above-ground biomass of the DJ treatment was the highest after 110 days of sowing (P<0.05), followed by the DD treatment, while there was no difference in the above-ground biomass of potato between DY and CK (P>0.05). Higher potato yield and water-use efficiency was found with DD, DJ, DS and DM treatments. The yield and water use efficiency of potato with DJ treatment were the highest (37 213.5 kg/hm2 and 81.1 kg/(hm2·mm)). Compared with CK, the potato yield with DD, DJ, DS and DM treatments was significantly (P<0.05) increased by 34.3%, 56.1%, 8.6%, and 11.3%, meanwhile the water-use efficiency increased by 39.3%, 65.9%, 14.7%, and 14.3% (P<0.05). In a word, when ridges were covered with common plastic film, the furrows were mulched with straw, the soil water and temperature conditions were improved and potato growth and development was promoted, and the potato yield and water use efficiency were increased. Therefore, we suggested that plastic film mulched ridges and straw mulched furrows should be popularized and applied in arid area of southern Ningxia. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.