Soil nitrate-N levels required for high yield maize production in the North China Plain

Abstract

High profile nitrate-nitrogen (N) accumulation has caused a series of problems, including low N use efficiency and environmental contamination in intensive agricultural systems. The key objective of this study was to evaluate summer maize (Zea mays L.) yield and N uptake response to soil nitrate-N accumulation, and determine soil nitrate-N levels to meet N demand of high yield maize production in the North China Plain (NCP). A total of 1,883 farmers' fields were investigated and data from 458 no-N plots were analyzed in eight key maize production regions of the NCP from 2000 to 2005. High nitrate-N accumulation (C172 kg N ha -1 ) was observed in the top (0-90 cm) and deep (90-180 cm) soil layer with farmers' N practice during maize growing season. Across all 458 no-N plots, maize grain yield and N uptake response to initial soil nitrate-N content could be simulated by a linear plus plateau model, and calculated minimal pre-planting soil nitrate-N content for maximum grain yield and N uptake was 180 and 186 kg N ha -1 , respectively, under no-N application conditions. Economically optimum N rate (EONR) decreased linearly with increasing pre-planting soil nitrate-N content (r 2 = 0.894), and 1 kg soil nitrate-N ha -1 was equivalent to 1.23 kg fertilizer-N ha -1 for maize production. Residual soil nitrate-N content after maize harvest increased exponentially with increasing N fertilizer rate (P \ 0.001), and average residual soil nitrate-N content at the EONR was 87 kg N ha -1 with a range from 66 to 118 kg N ha -1 . We conclude that soil nitrate-N content in the top 90 cm of the soil profile should be maintained within the range of 87-180 kg N ha -1 for high yield maize production. The upper limit of these levels would be reduce if N fertilizer was applied during maize growing season.

Optimizing nitrogen input by balancing winter wheat yield and residual nitrate-N in soil in a long-term dryland field experiment in the Loess Plateau of China

“…Many studies have investigated NR in soil relative to excessive N inputs (Cui et al, 2008(Cui et al, , 2010Lenka et al, 2013). However, information on regulating NR in soil based on optimizing N fertilizer input and at the same time ensuring a satisfactory grain yield is still scarce in China, especially in drylands.…”

The Impact of Agricultural Extension on Farmer Nutrient Management Behavior in Chinese Rice Production: A Household-Level Analysis

“…Cui et al [14] found that using improved nutrient management technologies could reduce N fertilizer use by 40% without lowering maize yields, compared with current farming practices. Therefore, the timely delivery of science-based fertilizer recommendations through education, training and extension services is essential for improving nutrient use efficiency and for reducing the over-application of nutrients [15].…”

Wheat root growth responses to horizontal stratification of fertiliser in a water-limited environment

“…Excessive fertilizer (especially N) application and poor management has contributed to high soil nitrate-N accumulation and losses of N to the environment (Ju et al 2006;Qiu et al 2012). Soil NO 3 − -N enriched in the top 90 or 100 cm of the soil was above 200 kg N ha −1 under conventional N practice in intensive wheat-maize systems Cui et al 2008). When soil nitrate levels are high, root biomass and root to shoot ratio decrease, more roots are found in the topsoil layer and root growth, especially of lateral roots, is depressed (Durieux et al 1994;Wang et al 2003;Mi et al 2010).…”