Optimization of Sowing Date, Irrigation, and Nitrogen Management of Summer Maize Using the DSSAT-CERES-Maize Model in the Guanzhong Plain, China

Abstract

HighlightsGood applicability of DSSAT was validated in simulating summer maize yield in the Guanzhong Plain, China.Optimal sowing dates of summer maize were obtained for different climatic years.The optimal irrigation and nitrogen management strategy conserved water and nitrogen. Abstract. Agricultural system models play an important role in simulating crop growth processes and water and fertilizer regulation in arid regions. To solve the current problems of optimizing the sowing date in different climatic years and the fertilizer application in low-precipitation conditions in the Guanzhong Plain, China, this study used two years (2016-2017) of experimental summer maize field data to calibrate and validate Decision Support System for Agro-technology Transfer (DSSAT) model parameters. The validated DSSAT model was then used to simulate and optimize sowing dates, irrigation, and fertilization of summer maize crops in the Guanzhong Plain. The relative root-mean-square error (nRMSE) between the measured and simulated values of summer maize crop yield was 8.57%, proving that the established DSSAT model and crop parameters were highly reliable. The nRMSE values for soil water content and nitrate-nitrogen were 7.86% and 8.72%, respectively, which indicated better simulation results. The optimal sowing date for summer maize in the Guanzhong Plain were mid- to late June, mid-June, and early to mid-June in wet, general, and dry years, respectively. The irrigation and nitrogen strategies for summer maize in the climatic years were as follows: 60 mm and 180 kg ha-1 in wet years, 60 mm and 180 kg ha-1 in general years, and 150 mm and 150 kg ha-1 in dry years. This study provides a scientific decision-making method for the production of summer maize to conserve water and fertilizer. Keywords: . Climatic year, DSSAT, Guanzhong Plain, Sowing date, Summer maize.

Tracing the Sources and Fate of NO3– in the Vadose Zone–Groundwater System of a Thousand-Year-Cultivated Region

“…Optimal fertilization strategies to reduce NO 3 – accumulation in deeper soils while still meeting crop demand should also be considered . In the GP, the N fertilizer application rate varies greatly among farmers, both in croplands and orchards, and their averages significantly exceed the recommended application rate, resulting in a comparatively high N surplus . Inappropriate management practices can also result in excessive N input into the field.…”

“…Therefore, optimal agricultural water management practices and irrigation schedules to delay historical NO 3 – transport to the aquifer should be considered. Conventional flood irrigation remains the dominant irrigation strategy in the GP, , with the annual average irrigation far exceeding the optimal amount . A study conducted near the GP quantified the main depth of root water uptake of apple trees and indicated that the traditional surface irrigation depth should be reduced to decrease percolation below the root zone, thus increasing water savings .…”

“…70 In the GP, the N fertilizer application rate varies greatly among farmers, both in croplands and orchards, and their averages significantly exceed the recommended application rate, resulting in a comparatively high N surplus. 71 Inappropriate management practices can also result in excessive N input into the field. For instance, irrigation water is an important N resource for agricultural systems, 53,72 but is often ignored by farmers when applying fertilizers.…”

“…Conventional flood irrigation remains the dominant irrigation strategy in the GP, 13,74 with the annual average irrigation 75 far exceeding the optimal amount. 71 A study conducted near the GP quantified the main depth of root water uptake of apple trees and indicated that the traditional surface irrigation depth should be reduced to decrease percolation below the root zone, thus increasing water savings. 76 Therefore, considering the history of NO 3 − inputs to the vadose zone and the potential risk of groundwater NO 3 − pollution in the GP, the development of smart water-saving technologies and optimal irrigation strategies is encouraged to reduce irrigation rates and thus slow the NO 3 − leaching rates.…”

A modified DSSAT‐CERES model for simulating summer maize growth under film mulching

“…The decision support system for agricultural technology transfer (DSSAT) is one of most widely used crop models for yield prediction (Anar et al, 2019;Dokoohaki et al, 2015;Shen, Xu, et al, 2020;Yakoub et al, 2017), water management (Haberle & Svoboda, 2014;Ben Nouna et al, 2000;Saïdou et al, 2018), and drought reduction (L. Bai et al, 2004;Chen et al, 2013;Igbadun et al, 2008;Shen, Chen, et al, 2020). Crop environment resource synthesis (CERES), a module of DSSAT model, can simulate crop production parameters including growth period and dry matter allocation for crops such as rice (Oryza sativa L.), maize, and wheat (Triticum aestivum L.).…”