Abstract:

【Objective】The management of farmers is the main mode of agricultural production in China, and the unreasonable application of fertilizer resources is the crucial factor in limiting the production of crops. This study was aimed to assess the potential of fertilizer reduction and benefits of environment and economic, which was very important for agricultural sustainable development in the main crop production regions.【Method】In 2018, a questionnaire survey was conducted on the production of major crops in counties (cities and districts) of Shaanxi Province. The three major crops were taken as research objects to evaluate farmers’ fertilization status, fertilizer reduction potential, environmental costs and economic benefits based on yield level.【Result】There were significant differences in farmers’ crop yields. The average yield of wheat was 4 573 kg·hm^-2, and the difference between high and low yield was 2 619 kg·hm^-2; the average yield of maize was 7 319 kg·hm^-2, and the difference between high and low yield was 5 388 kg·hm^-2; the average yield of rice was 8 340 kg·hm^-2, and the difference between high and low yield was 2 893 kg·hm^-2. The nitrogen, phosphorus and potassium rate of wheat was 177 kg N·hm^-2, 102 kg P₂O₅·hm^-2 and 37 kg K₂O·hm^-2, respectively; maize was 247 kg N·hm^-2, 103 kg P₂O₅·hm^-2 and 47 kg K₂O·hm^-2; rice was 186 kg N·hm^-2, 88 kg P₂O₅·hm^-2 and 64 kg K₂O·hm^-2. There is no significant relationship between yield and fertilizer application. The problems of excessive application of nitrogen and phosphate fertilizer, excessive and insufficient potassium fertilizer coexist, and excessive fertilization in low-yield farmers was serious. The reduction potential of nitrogen, phosphorus, potassium in wheat was 41%, 59% and 59%, respectively; maize was 55%, 73% and 66%, respectively; for rice, it was 38%, 64% and 58%, respectively. The forms of fertilizers applied showed that nitrogen was mainly chemical fertilizers and supplemented by compound fertilizers; phosphorus and potassium were mainly compound fertilizers; the organic manure supplied very low nutrient. The application of basal fertilizer usually received more attention, while topdressing was often overlooked on fertilizer structure, nitrogen was mainly based on basal application and supplemented by topdressing; phosphorus and potassium fertilizers were rarely applied topdressing. Losses of reactive nitrogen to produce 1.0 t wheat, maize and rice were 6.9, 3.8 and 3.3 kg N, respectively. Compared with the high-yield group, the reactive nitrogen loss intensity of wheat, maize and rice in the low-yield group increased by 52%, 85% and 74%; the potential of loss reduction ranges of wheat, maize and rice in low-yield group were 16%-33%, 31%-50% and 4%-38%, respectively. The economic benefits of wheat, maize and rice production were 4 468, 9 091 and 20 020 yuan/hm², respectively. Compared with the low-yield group, the economic benefits of wheat, maize and rice in high-yield group increased 455%, 128% and 52%, respectively. The benefit increases were 4 919, 9 905 and 20 543 yuan/hm². Compared with the low-yield group, the benefit increases of wheat, maize and rice in high-yield group increased 290%, 106% and 48%, respectively.【Conclusion】The household production behavior was analyzed deeply based on the production level in Shaanxi province. The low and middle yield levels were the focus of fertilizer reduction and benefit improvement. The average reduction potential of nitrogen, phosphorus, and potassium fertilizers for the three crops was 45%, 65% and 61%, respectively, reducing the potential of active nitrogen loss were 26%, 45% and 18%, respectively. The potential to improve environment economic benefits were 10%, 9% and 3%, respectively.

Key words: household behavior, nutrients management, cereal crops, yield, environmental cost, economic benefit, Shaanxi Province