Effects of irrigation and nitrogen application rates on nitrate nitrogen distribution and fertilizer nitrogen loss, wheat yield and nitrogen uptake on a recently reclaimed sandy farmland

Abstract

Monitoring of drinking water has shown an increase in nitrate-nitrogen (NO 3 − -N) concentration in groundwater in some areas of the Heihe River Basin, Northwest China. A combination of careful irrigation and nitrogen (N) management is needed to improve N uptake efficiency and to minimize fertilizer N loss. A 2-year experiment investigated the effects of different irrigation and N application rates on soil NO 3 − -N distribution and fertilizer N loss, wheat grain yield and N uptake on recently reclaimed sandy farmland. The experiment followed a completely randomized split-plot design, taking flood irrigation (0.6, 0.8 and 1.0 of the estimated evapotranspiration) as main plot treatment and N-supply as split-plot treatment (with five levels of 0, 79, 140, 221, 300 kgN ha −1 ). Fertilizer N loss was calculated according to N balance equation. Our results showed that, under deficit irrigation conditions, N fertilizer application at a rate of 300 kgha −1 promoted NO 3 − -N concentration in 0-200 cm depth soil profiles, and treatments with 221 kgN ha −1 also increased soil NO 3 − -N concentrations only in the surface layers. Fertilizer N rates of 70 and 140 kgha −1 did not increase NO 3 − -N concentration in the 0-200 cm soil profile remaining after the spring wheat growing season. The amount of residual NO 3 − -N in soil profiles decreased with the amount of Plant Soil (2010) 337:325-339irrigation. Compared with N 0 , the increases of fertilizer N loss, in N 79 , N 140 , N 221 and N 300 respectively, were 59.9, 104.6, 143.5 and 210.6 kg ha −1 over 2 years. Under these experimental conditions, a N rate of 221 kgha −1 obtained the highest values of grain yield (2775 kgha −1 ), above-ground dry matter (5310 kg ha −1 ) and plant N uptake (103.8 kgha −1 ) over 2 years. The results clearly showed that the relative high grain yield and irrigation water productivity, and relative low N loss were achieved with application of 221 kgN ha −1 and low irrigation, the recommendation should be for those farmers who use the upper range of the recommended 150-400 kgN ha −1 , that they can save about 45% of their N and 40% of their irrigation water application.

Sustainability in Cereal Crop Production in Mediterranean Environments

“…In particular, nitrogen fertilization increases the yield response at all water regimes by improving the utilization of water resources. As also, a higher water intake improves nitrogen use efficiency at each of the five doses of nitrogen fertilizer supplied to the crop (Wang et al 2010).…”

“…In subhumid and arid environments, slopes should not exceed 1 % and fields may be as wide as possible (usually over 30-50 m) in order to increase the water traveling time on the soil crop water use (ET) Fig. 4 Response of durum wheat grain yield to the soil water regime and nitrogen fertilization (redrawn from Wang et al 2010) surface and thus facilitate retention and water infiltration before it is intercepted by the ditch and removed from the field. In sloping land water losses for runoff are generally higher, and surface water and sediment control is strategic for improving soil fertility.…”

“…In synthesis, the availability of water favors the removal of nutrients and the efficiency of their use on one side; on the other side the availability of nutrients favors plant and root growth, and this in turn improves the removal of water and its efficiency (Zhong and Shangguan 2014). Figure 4 shows the response of durum wheat production to a combination of water and fertilization regimes in an experiment conducted by Wang et al (2010). In particular, nitrogen fertilization increases the yield response at all water regimes by improving the utilization of water resources.…”

Impact of Groundwater Level on Nitrate Nitrogen Accumulation in the Vadose Zone Beneath a Cotton Field

“…The thickness of the aeration zone changes as the groundwater level changes, which affects soil water and solute transport [21]. Selecting the optimum nitrogen use and irrigation rate can reduce nitrate nitrogen losses, improve the nitrogen use efficiency and decrease groundwater nitrate pollution on the North China Plain [22]. Hence, the distribution and transport of nitrate nitrogen based on agricultural irrigation has been studied in South China [23] and North China [24].…”

Sources and Dynamics of Dissolved Inorganic Carbon, Nitrogen, and Phosphorus in a Large Agricultural River Basin in Arid Northwestern China

“…In the HRB, soil nutrients have increased over the past few decades due to intensive uses of agricultural fertilizers [12,13]. The complex hydrological processes in the basin, however, is another important factor mediating watershed-river nutrient connectivity.…”