Negative effects of climate warming on maize yield are reversed by the changing of sowing date and cultivar selection in Northeast China

Abstract

Northeast China (NEC) accounts for about 30% of the nation's maize production in China. In the past three decades, maize yields in NEC have increased under changes in climate, cultivar selection and crop management. It is important to investigate the contribution of these changing factors to the historical yield increases to improve our understanding of how we can ensure increased yields in the future. In this study, we use phenology observations at six sites from 1981 to 2007 to detect trends in sowing dates and length of maize growing period, and then combine these observations with in situ temperature data to determine the trends of thermal time in the maize growing period, as a measure of changes in maize cultivars. The area in the vicinity of these six sites accounts for 30% of NEC's total maize production. The agricultural production systems simulator, APSIM-Maize model, was used to separate the impacts of changes in climate, sowing dates and thermal time requirements on maize phenology and yields. In NEC, sowing dates trended earlier in four of six sites and maturity dates trended later by 4-21 days. Therefore, the period from sowing to maturity ranged from 2 to 38 days longer in 2007 than it was in 1981. Our results indicate that climate trends alone would have led to a negative impact on maize. However, results from the adaptation assessments indicate that earlier sowing dates increased yields by up to 4%, and adoption of longer season cultivars caused a substantial increase in yield ranging from 13% to 38% over the past 27 years. Therefore, earlier sowing dates and introduction of cultivars with higher thermal time requirements in NEC have overcome the negative effects of climate change and turned what would have otherwise been a loss into a significant increase in maize yield.

Impact of warming climate and cultivar change on maize phenology in the last three decades in North China Plain

“…As noted in this study, warmer climate speeds up crop development and thereby decreases the duration of maize growth period (Liu et al 2013). In 1981-2008, maize growth season (which is mainly from June to September) experiences increasing warming conditions.…”

“…Obvious reductions in the length of crop growth seasons due to warming climate are extensively documented in several studies (Porter 2005;Tao et al 2006;Estrella et al 2009;Tao and Zhang 2010;Zhang et al 2013;Xiao et al 2013a, b). Other studies have noted that climate change accelerates crop growth processes, with direct negative impact on crop yield (Liu et al 2013;Xiao and Tao 2014).…”

“…For example, the adoption of cultivars with longer growth periods could increase yield under climate change due to higher heat accumulation (Wang et al 2012;Liu et al 2013;Xiao and Tao 2014). Crop phenological processes are driven by the combined effects of climate variability and agronomic factors such as cultivar shifts and management practices, which are to some extent controlled by man (Liu et al 2010;Xiao and Tao 2014).…”

Responses of Agroecosystems to Climate Change: Specifics of Resilience in the Mid-Latitude Region

“…The Agricultural Production Systems sIMulator (APSIM) model (http://www.apsim.info) simulates specific crop yields by calculating interactions among plants, animals, soil, climate, and management practices [27][28][29]. APSIM has been widely used for various regions of a wide range of environmental characteristics with multiple field experiments [30][31][32][33][34]. The model has been used to study the potential impact of climate change on crop productivity [35][36][37][38][39].…”

Historical data provide new insights into response and adaptation of maize production systems to climate change/variability in China

“…Modern breeding increased ear fertility and grain-filling rate, and delayed leaf senescence without modification in net photosynthetic rate. Recently, Liu et al (2013) indicated that earlier sowing dates and introduction of cultivars with higher thermal time requirements in northeastern China had overcome the negative effects of climate change during , through a crop model analyses. These results support our findings that observed yield trend ranged from 12.74 kg ha −1 (0.26%) to 243.07 kg ha −1 (4.3%) per year, with an average of 128.84 kg ha −1 (2.4%) per year, mainly due to cultivars turnover and advance in agronomic management (Table 3).…”