Response of Water-Nitrogen Distribution and Use to Water Deficit under Different Applied Nitrogen Fertilizer Rates in Bromus inermis Grassland

This study was about the water-nitrogen regulation model and its soil nutrient environment effect for increasing yield efficiency of Bromus inermis in Hexi Corridor, Gansu Province, China. used as research object this four irrigation management types nitrogen application levels were set. The (controlled by percentage field capacity (θf) at jointing stage) 75–85% (W0), 65–85% (W1), 55–85% (W2) 45–85% (W3). pure 0 kg·ha−1 (N0), 60 (N1), 120 (N2) 180 (N3). effects on spatial temporal distribution moisture nitrate (NO3−–N), plant height, chlorophyll content, use studied. Results demonstrated that (1) water content (SWC) mainly affected W1 treatment helped maintain shallow (0–40 cm) water’s stability avoided redundancy or deficit 60–80 cm layer. NO3−–N application. N2 could effectively increase prevent nitrate-nitrogen leaching 60–100 (2) Irrigation significantly height each cut inermis. average N2W1 66.99% 30.30% higher than N0W3. (3) At same time, inermis, interaction between two had a significant total yield. highest (12,259.54 kg·ha−1), 157.95% improve their only impacted partial-factor productivity applied (PFPN). Meanwhile, N2W2 (WUE) (23.12 kg·m−3), N1W1 PFPN (170.87 kg·kg−1). In summary, moderate rate (120 kg·ha−1) combined with mild (65–85% θf not promote high but also avoid deep soil. It is suitable mode Corridor