Planting trees in saline soil using ridge cultivation with drip irrigation in an arid region of China

Abstract

AbstractLand degradation due to soil salinization is a widespread problem in arid and semiarid areas. In the Hetao Irrigation District in the upper reaches of the Yellow River in China, nearly one‐third of the land is salinized. To improve the environment in these salt‐affected regions, we conducted a field experiment in the Hetao Irrigation District from 2018 to 2020 that involved planting poplar and willow trees in saline soil using ridge cultivation with drip irrigation. After 3 years of water–salt regulation by drip irrigation, soil salinity at 0–40 and 0–120 cm with initial values of 12.22 and 8.27 dS m−1 was reduced by 85.19% and 68.56%, respectively. The survival rates of the seedlings were 99.3% (poplar) and 99.4% (willow) in the first year, and 90.6% (poplar) and 95.8% (willow) in the third year. Moreover, drip irrigation used 42.19% less water for salt leaching than other common methods. In addition, understory vegetation gradually established, and its species, coverage, and density increased year by year. A plant community structure gradually developed that comprised Poaceae and Asteraceae. In general, we found that ridge cultivation with drip irrigation led to an improved the soil environment which affected the development of the ecosystem shifting it in a stable, healthy, and sustainable direction. Taken together, our results indicate that ridge cultivation with drip irrigation can decrease soil salinity and produce ecological benefits.