Spatial distribution of wheat and maize straw resources and nutrient utilization potential under straw return in Henan Province
Henan is the main wheat and maize production province in China.Clarifying the spatial distribution pattern of straw resources from staple crops at the municipal level and evaluating the potential of replacing chemical fertilizer under straw return could offer important references for the optimization of comprehensive straw utilization policies and farmland nutrient management measures.Based on the sown area and yield of wheat and maize of 18 cities in the Henan Province from 2018 to 2020,the quantity of major crops straw resources,collectable straw per unit sown area,and chemical fertilizer reduction potential under straw return were estimated using straw/grain ratio and nutrients content of straw collected from relevant literature.The annual outputs of wheat and maize straw were 41.685 millions and 19.443 million tons in the Henan Province during 2018-2020,respectively.At the municipal level,the wheat and maize straw resources were mainly distributed in Zhoukou(6.113 million and 2.840 million tons),Zhumadian(5.792 million and 2.169 million tons),Shangqiu(4.937 million and 2.353 million tons),and Nanyang(4.706 million and 1.966 million tons).The wheat and maize straw yields of these cities accounted for 51.7% and 48.0%,respectively.However,the total proportions of wheat and maize straw outputs from Zhengzhou,Hebi,Sanmenxia,and Jiyuan were only 5.0% and 7.1%,respectively.The amounts of nutrients from wheat straw were 0.198 million tons of N,0.073 million tons of P2O5,and 0.725 million tons of K2O in the Henan Province.The outputs of nutrients from maize straw were 0.144 million tons of N,0.057 million tons of P2O5,and 0.316 million tons of K2O.The substituting potentials of N,P2O5,and K2O through wheat straw return in the Henan Province was 17.8,8.3 kg·hm-2,and 118.3 kg·hm-2,respectively.Moreover,maize straw incorporation could substitute synthetic fertilizers of N 23.7,P2O5 11.0 kg·hm-2,and K2O 77.7 kg·hm-2 theoretically.The results indicate that wheat and maize straw resources are abundant in the Henan Province;however,the spatial distribution of straws is unbalanced at the city scale.The main straw-producing cities should be emphasized to promote the full quantitative utilization of straws with high quality and efficiency.Moreover,returning wheat and maize straw to the field could provide a feasible pathway for rational replacement and reduction of chemical fertilizer usage.
国家科技期刊平台
NSTL
万方数据
