Soil mulching can mitigate soil water deficiency impacts on rainfed maize production in semiarid environments

Abstract

Temporally irregular rainfall distribution and inefficient rainwater management create severe constraints on crop production in rainfed semiarid areas. Gravel and plastic film mulching are effective methods for improving agricultural productivity and water utilization. However, the effects of these mulching practices on soil water supply and plant water use associated with crop yield are not well understood. A 3-yr study was conducted to analyze the occurrence and distribution of dry spells in a semiarid region of Northwest China and to evaluate the effects of non-mulching (CK), gravel mulching (GM) and plastic film mulching (FM) on the soil water supply, plant water use and maize (Zea mays L.) grain yield. Rainfall analysis showed that dry spells of ≥5 days occurred frequently in each of 3 yr, accounting for 59.9-69.2% of the maize growing periods. The >15-d dry spells during the jointing stage would expose maize plants to particularly severe water stress. Compared with the CK treatment, both the GM and FM treatments markedly increased soil water storage during the early growing season. In general, the total evapotranspiration (ET) was not significantly different among the three treatments, but the mulched treatments significantly increased the ratio of pre-to post-silking ET, which was closely associated with yield improvement. As a result, the grain yield significantly increased by 17.1, 70.3 and 16.7% for the GM treatment and by 28.3, 87.6 and 38.2% for the FM treatment in 2010, 2011 and 2012, respectively, compared with the CK treatment. It's concluded that both GM and FM are effective strategies for mitigating the impacts of water deficit and improving maize production in semiarid areas. However, FM is more effective than GM.

Effects of the ridge mulched system on soil water and inorganic nitrogen distribution in the Loess Plateau of China

“…The yield increases for RM-N260 and RM-N180, compared with F-N260 and F-N180, were 79 and 123% in 2013, 23 and 25% in 2014, and 12 and 11% in 2015, respectively. Several studies have shown that ET (or the contribution of transpiration to ET) and water use during pre-silking stage has a positive relationship with grain yield ( Zhang et al, 2014 ; Zhu et al, 2015 ), as observed in our study. The highest yields occurred in 2014 both in RM and F, associated with much higher precipitation and lower evaporation before sowing (and a much higher SWS before sowing, Fig.…”

“… Zhang et al (2014) also found a significant correlation between crop yield and soil water content at sowing on the Loess Plateau. Zhu et al (2015) found SWS at sowing had a significant positive relationship with ET during the pre-silking stage. We also observed higher ET during the pre-silking stage associated with higher SWS at sowing ( Table 3 ).…”

“…These finding suggest that maize grain yield was not limited by the amount of rainfall during the maize growing season or the cumulative annual rainfall but by the irregular distribution of rainfall over time and the inefficient management of rainwater in semiarid areas ( Zhu et al, 2015 ). Many studies have indicated that increasing rainwater harvest, improving soil water storage, and increasing plant water uptake capacity by using different cultivation systems could optimize crop productivity in rain-fed areas ( Kahinda et al, 2007 ; Zhu et al, 2015 ). In our study, the maize grain yields were significantly higher in RM than that in F treatments ( Table 3 ).…”

“…Water is the most limiting factor for crop production under rain-fed agriculture in arid and semiarid areas. However, studies have shown that the temporally irregular rainfall distribution and inefficient management of rainwater, rather than total rainfall amount, are the primary limits for crop production ( Barron et al, 2003 ; Zhu et al, 2015 ). Zhu et al (2015) indicated that plastic film mulching improved rainwater management to overcome water limitations during dry spells, which promoted crop growth and increased yields significantly.…”

“…However, studies have shown that the temporally irregular rainfall distribution and inefficient management of rainwater, rather than total rainfall amount, are the primary limits for crop production ( Barron et al, 2003 ; Zhu et al, 2015 ). Zhu et al (2015) indicated that plastic film mulching improved rainwater management to overcome water limitations during dry spells, which promoted crop growth and increased yields significantly. Drought and mild chilling stress often occur in the Loess Plateau of China, especially during the early stage of the maize growing season; plastic film mulching can improve the soil water content and temperature during this stage resulting in increased yield ( Jiang et al, 2016 ; Zhang et al, 2014 ).…”