Improving smallholder farmers' maize yields and economic benefits under sustainable crop intensification in the North China Plain

Hao Ren; Kun Han; Yuee Liu; Yali Zhao; Lihua Zhang; Qijin He; Zhenhai Li; Jibo Zhang; Peng Liu; Hongzhang Wang; Jiwang Zhang; Bin Zhao

doi:10.1016/j.scitotenv.2020.143035

Improving smallholder farmers' maize yields and economic benefits under sustainable crop intensification in the North China Plain

Sci Total Environ. 2021 Apr 1:763:143035. doi: 10.1016/j.scitotenv.2020.143035. Epub 2020 Oct 20.

Authors

Hao Ren¹, Kun Han¹, Yuee Liu², Yali Zhao³, Lihua Zhang⁴, Qijin He⁵, Zhenhai Li⁶, Jibo Zhang⁷, Peng Liu⁸, Hongzhang Wang¹, Jiwang Zhang¹, Bin Zhao¹

Affiliations

¹ State Key Laboratory of Crop Biology and College of Agronomy, Shandong Agricultural University, Tai'an 271018, Shandong, China.
² Beijing Maize Seed Testing Center, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
³ College of Agronomy, Henan Agricultural University, Zhengzhou 450046, Henan, China.
⁴ Institute of Cereal and Oil Crops, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang 050035, China.
⁵ College of Resources and Environmental Sciences, China Agricultural University, Beijing 100097, China.
⁶ Beijing Research Center for Information Technology in Agriculture, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
⁷ Shandong Climate Center, Jinan 250031, Shandong, China.
⁸ State Key Laboratory of Crop Biology and College of Agronomy, Shandong Agricultural University, Tai'an 271018, Shandong, China. Electronic address: liupengsdau@126.com.

PMID: 33131864
DOI: 10.1016/j.scitotenv.2020.143035

Abstract

To meet the food demands of a growing population, the maize production systems deployed by smallholders in China have tended towards extremely intensive planting and excessive use of fertilizers, which have caused serious environmental impacts. This study investigated the balance between the maize yield and nitrogen (N) input in the North China Plain (NCP), which is one of the most important grain-producing region in China. Our study compared yield simulations generated by the DSSAT-CERES-Maize model with actual data from a number of multi-site field experiments and an extensive household surveys encompassing 1671 farmers. The smallholders' maize cultivars, plant population, and amount of N input on the crop yield and how these affects the economic benefits were analyzed. The results showed that the average traditional farming methods' yield was 72% of the attainable yield, which means that farmers have ample room to improve their yields. We also found that the maize yields varied widely between farmers, and that most of them applied excessive amounts of N but failing to achieve an optimal yield due to poor fertilization management techniques. The study found that the economic benefits achieved by the farmers were low, but after deploying high-yield (HY) methods, the yield was increased by 34.9% and the economic benefits by 14.4%. The greenhouse gas (GHG) emissions associated with the traditional farming methods were high and could potentially be reduced by 48.6%. All in all, farmers should be given guidance on how to appropriately increase the plant population, reduce the input of N fertilizer, and optimize farmland management measures, so that China can achieve intensive but sustainable agricultural production at a lower environmental cost. It was concluded that there are still numerous biological and abiotic factors that restrict production increases by smallholders. These factors vary from region to region and require further investigation.

Keywords: Agricultural sustainability; Fertilizer management; Maize cultivar; Plant population; Yield gaps.