Combined Effects of Mulch and Tillage on Soil Hydrothermal Conditions under Drip Irrigation in Hetao Irrigation District, China

Abstract

Soil hydrothermal condition is one of the most important factors affecting crop growth in arid regions. This study aimed to investigate the effect of mulching and tillage on moisture and temperature variations in soil under drip irrigation in the arid Hetao Irrigation District, northwest China. Four treatments were included: (1) alternating ridges (40 cm wide and 20 cm high) and furrows (40 cm wide) with plots fully mulched with plastic film (RFM); (2) alternating ridges (40 cm wide and 20 cm high) and furrows (40 cm wide) with partial film mulch (only the plant rows mulched) (RPM); (3) flat tillage with plots fully mulched with plastic film (FFM); and (4) flat tillage with partial film mulch (only the plant rows mulched) (FPM). The ridge tillage and plastic film increased soil temperature and significantly conserved soil water, and thus increased the maize yield and water use efficiency (WUE). The RFM treatment had a greater effect than the RPM, FFM, and FPM treatments on the soil moisture and water storage over 0-70 cm in depth during the entire growing period in 2014 and 2015, indicating that full transparent plastic film mulch increased soil water status and promoted deep water percolation, and ridge tillage further enhanced water redistribution to deep soils. Furthermore, RFM proportionally increased soil temperature by 0.36 • C, 1.49 • C, and 1.27 • C above the temperatures under RPM, FPM, and FFM, respectively, in 2014 and by 1.19 • C, 1.62 • C, and 0.35 • C, respectively, in 2015. During the drought year of 2014, tillage influenced temperature more than mulching; however, mulching played a more important role in preserving thermal conditions than tillage during the humid year of 2015. Consequently, RFM increased the maize yield and WUE significantly. We conclude that a combined system of full plastic film mulch and ridge tillage creates beneficial soil hydrothermal conditions under drip irrigation and thus promotes the growth and performance of field crops.

Plastic film mulching stimulates brace root emergence and soil nutrient absorption of maize in an arid environment

“…Before maize elongation stage, plant growth (such as SD and LA) in FM plots was greater than in PM plots (Fig. ); these results were in accord with the study of Qi et al . in the Hetao Irrigation District.…”

“…Mulching treatments exhibited higher RLD than did NM; this could be attributed to higher soil temperatures in mulching plots, 27 which benefit fine root emergence. 37 Previous studies have found that root growth was reduced in the surface soil under full compared to partial mulching; this was due to poor soil aeration.…”

“…where RSA is root surface area per plant (m 2 ); RSA LC is summed RSA in 0-120 cm soil depth between drip lateral and crop row; RSA 0-10 , RSA [10][11][12][13][14][15][16][17][18][19][20] , and RSA [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] are summed RSA in 0-120 cm soil depth at horizontal distances 0-10, 10-20, and 20-35 cm away from the crop row, respectively.…”

Simulation of Hydrology and Nutrient Transport in the Hetao Irrigation District, Inner Mongolia, China

“…The mean annual precipitation is 180 mm, of which 80% occurs from June-August. The annual potential evaporation is about 2200-2400 mm, the mean annual temperature in the region is about 6-8 • C and the freeze-up period typically lasts for 5 to 6 months of each year [23]. Soil freezes from late November to early May, and the maximum frost depth is typically 1-2 m. The soil parent material of the area is predominantly alluvium deposited by the Yellow River.…”

Downscaling GLDAS Soil Moisture Data in East Asia through Fusion of Multi-Sensors by Optimizing Modified Regression Trees

“…Changes in soil moisture have a considerable impact on climate change [1]; hydrological processes, including precipitation, stream flow, and energy fluxes [2][3][4][5][6][7]; agricultural processes such as irrigation management and crop yield prediction [8,9]; and severe weather events such as droughts and heat waves [10][11][12][13][14][15][16]. Therefore, it is important to monitor temporal and spatial patterns of soil moisture.…”