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• The omission of P had a rather small effect on winter cereal yields. • Sugar beet, clover and potato yields were most affected by P deficiency. • Raising air temperature reduces yield loss caused by phosphorus limitation. Phosphorus (P) is an essential plant nutrient. However, our understanding of the complex interactions between soil P availability, environment, management and crop growth is still limited. We used unique historic and recent soil and crop data spanning more than a century combined with a process-based crop model to analyze the impact of P fertilizer omission and P fertilization on the biomass production of five crops. The long-term field experiment at Dikopshof, Germany, was established in 1904 with a 5-year crop rotation of sugar beet, winter wheat, winter rye, clover and oat/potato (potato replaced oat in 1953) on a fertile Luvisol. Averaged over the period from 1906 to 2018, the yield loss due to P omission was low for winter wheat and winter rye (7–8 %). In contrast, yield losses for sugar beet, clover and potato were relatively high (15–24 %). The yield loss from P fertilizer omission in comparison to the reference treatment (rotation mean excluding oat/potato) increased until the middle of the last century from 7% to 18 %, but subsequently decreased to 13 %. Trend and correlation analyses suggest that this decrease was related to an increase in air temperatures in especial during spring and a lower yield loss under P omission. Crop model simulations showed decreasing topsoil organic carbon concentrations after the 1930ies as manure was discontinued in 1942 but also due to increasing air temperatures. The increase in plant-available topsoil P concentrations during the last decades was one of the main factors offsetting yield losses despite P fertilizer omission. Our study suggests that climate change and, in particular, a marked increase in temperature since the middle of the last century most likely influenced soil P dynamics with a significant impact on crop production. [ABSTRACT FROM AUTHOR]

• Model-based estimation of spring wheat root growth, water, N and P uptake reveals importance of subsoil and pre-crops interactions. • Only in years with dry spell, subsoil N uptake by spring wheat was higher after chicory as pre-crop compared to fescue. • Lucerne as pre-crop induced an enhanced P and N uptake from deep soil layers by the following main crop. Water and nutrients in the subsoil are valuable resources in crop production but the availability varies with weather conditions and management, in particular the crop rotation. Moreover, constraints such as mechanical resistance or water stress may impede root growth into deeper soil layers. This study presents a simulation-based stochastic approach to investigate the impact of precrops on spring wheat growth and water and nutrient uptake under varying weather conditions. The effect of the three precrops lucerne, chicory and tall fescue on spring wheat growth was investigated extensively in a field trial. For model calibration and evaluation, we selected a year with a dry spell (2010) and one with abundant precipitation (2012) and used field data on biopore densities in the subsoil, crop development, leaf area index, shoot biomass, grain and straw yield, nitrogen (N) and phosphorus in shoot, grain and straw, root length densities, as well as soil moisture and soil N and P concentrations for several soil depths. The modeling framework consisted of the modeling platform SIMPLACE and the stochastic weather generator LARS-WG to consider climate variability. The weather generator was used to generate a synthetic time-series of daily weather data (100 years) based on observed weather data of the experimental site in order to simulate 100 spring wheat growth periods under recent climate conditions for each precrop. Moreover, a 100 year long time-series with annual dry spells in June was generated to analyze the effect of drought during flowering on crop water and nutrient uptake. During the scenario runs, the model was annually reinitialized at sowing to provide identical initial conditions. The experimental data over two years showed that spring wheat growth as well as total N and P uptake were clearly enhanced after precrop lucerne. This was comfirmed by the simulations over 100 years. The simulation runs also prompt that precrop fescue led to higher spring wheat biomass and enhanced subsoil and total water and N uptake in years with normal precipitation pattern compared to precrop chicory, but in drier years, it was vice versa. Because plants compensate for moderate nutrient or water deficiencies, small differences in grain yield may hide significant differences in total and in subsoil N and P uptake. [ABSTRACT FROM AUTHOR]