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Scientific facts about the relationships between the goals are indispensable for the rational social discourse on solving the various conflicting goals on the way to sustainable crop production. Therefore, the German Society for Agronomy has compiled scientific findings on the topics of biodiversity, climate relevance and climate resilience, nutrient management, crop protection, soil protection and production of renewable raw materials, and identified the existing need for research. After an executive summary that highlights the findings, the subject areas are explained in detail. The purpose of this paper is not to make recommendations for policy-making, but to support the public debate by providing factual information.

Crop yields are increasingly affected by climate change-induced weather extremes in Germany. However, there is still little knowledge of the specific crop-climate relations and respective heat and drought stress-induced yield losses. Therefore, we configure weather indices (WIs) that differ in the timing and intensity of heat and drought stress in wheat (Triticum aestivum L.). We construct these WIs using gridded weather and phenology time series data from 1995 to 2019 and aggregate them with Germany-wide municipality level on-farm wheat yield data. We statistically analyze the WI's explanatory power and region-specific effect size for wheat yield using linear mixed models. We found the highest explanatory power during the stem elongation and booting phase under moderate drought stress and during the reproductive phase under moderate heat stress. Furthermore, we observed the highest average yield losses due to moderate and extreme heat stress during the reproductive phase. The highest heat and drought stress-induced yield losses were observed in Brandenburg, Saxony-Anhalt, and northern Bavaria, while similar heat and drought stresses cause much lower yield losses in other regions of Germany., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Riedesel et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Hydrothermal carbonization process via converting invasive plants into functional materials may provide a novel strategy to comprehensively control and utilized the exotic invasive plants. In this study, Eupatorium adenophorum was utilized to fabricate the hydrochar via hydrothermal carbonization process, which was further applied to remove Cd(II). The results showed that the hydrochar was a mesoporous material with abundant O-containing functional groups (OFPs) on the surface. The adsorption isotherms were fitted by both the Langmuir and Freundlich models, and the maximum adsorption amount achieved 24.53 mg/g. The adsorption dynamics were governed by surface adsorption and film diffusion. pH and ionic strength can exert a strong influence on the adsorption efficiency. The mechanisms on the adsorption of Cd(II) on the hydrochar concluded the pore-filling effects, electrostatic interactions, ion exchange, precipitation, coordination with π electrons, and surface complexation with the OFPs, such as hydroxyl, carboxylic, phenol, acetyl, and ester groups. Thus, hydrothermal carbonization process may provide a promising technique to fabricate the hydrocar for the treatment of Cd(II), which may facilitate comprehensive control of invasive plants and boost to the carbon neutrality., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Conversion of the low-valued invasive plant biomass into high-grade carbonaceous materials may provide a novel strategy to tackle the global issues of climate changes and exotic plant invasion. In this study, the hydrochar was fabricated from the biomass of Eupatorium adenophorum spreng. via hydrothermal carbonization (HTC) process to remove Cr(VI). The adsorption thermodynamics and kinetics were investigated via batch experiments, and the electron transfer routes and adsorption mechanisms were further revealed based on systematic characterization. The adsorption isotherms were well fitted by the Langmuir model with a maximum adsorption amount of 7.76 mg/g. The adsorption was spontaneous, and the surface adsorption and intraparticle diffusion may be the speed-limiting steps. Both -OH group and furan structures may donate the electrons to reduce Cr(VI), and the adsorption was governed by the surface complexation with the oxygen-containing functional groups including hydroxyl and carboxyl. Furthermore, the wood vinegar, as the by-product, can significantly accelerate the reduction rate of Cr(VI). Thus, this study provided a new strategy to fabricate carbonaceous materials which may facilitate to boost the carbon neutrality and control of invasive plants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

We need to produce higher foods even under declining natural resources to feed the projected population of 9 billion by 2050 and to sustain food security and nutrition. Abiotic stress has adversely affected canola crop and oil quality especially in sandy soils. To combat this stress, adaptation at the farm level using new and cost-effective amendments are required. Field trials were conducted in two different climatic zones to determine the efficacy of cane molasses, bagasse ash, sugar beet factory lime, and their compost mixtures to improve soil quality and heat stress-adapting canola. The results showed a significant improvement in bulk density, hydraulic conductivity, organic matter content, and available macronutrients of sandy soil and subsequent canola growth, yield, quality and water productivity due to the application of the tested soil amendments, particularly those mixed with compost. Despite the estimated reduction of yield by 18.5% due to heat stress, application of sugar beet lime and compost mixture not only compensated for this reduction but also increased the seed yield by 27.0%. These findings highlight the value of recycling compost-based sugar crop disposal as a cost-effective technology to boost crop tolerance to abiotic stress, ensuring sustainable agriculture and food security in arid environments., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Yield development of agricultural crops over time is not merely the result of genetic and agronomic factors, but also the outcome of a complex interaction between climatic and site-specific soil conditions. However, the influence of past climatic changes on yield trends remains unclear, particularly under consideration of different soil conditions. In this study, we determine the effects of single agrometeorological factors on the evolution of German winter wheat yields between 1958 and 2015 from 298 published nitrogen (N)-fertilization experiments. For this purpose, we separate climatic from genetic and agronomic yield effects using linear mixed effect models and estimate the climatic influence based on a coefficient of determination for these models. We found earlier occurrence of wheat growth stages, and shortened development phases except for the phase of stem elongation. Agrometeorological factors are defined as climate covariates related to the growth of winter wheat. Our results indicate a general and strong effect of agroclimatic changes on yield development, in particular due to increasing mean temperatures and heat stress events during the grain-filling period. Except for heat stress days with more than 31°C, yields at sites with higher yield potential were less prone to adverse weather effects than at sites with lower yield potential. Our data furthermore reveal that a potential yield levelling, as found for many West-European countries, predominantly occurred at sites with relatively low yield potential and about one decade earlier (mid-1980s) compared to averaged yield data for the whole of Germany. Interestingly, effects related to high precipitation events were less relevant than temperature-related effects and became relevant particularly during the vegetative growth phase. Overall, this study emphasizes the sensitivity of yield productivity to past climatic conditions, under consideration of regional differences, and underlines the necessity of finding adaptation strategies for food production under ongoing and expected climate change., (© 2020 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

The major wheat production region of China the North China Plain (NCP) is seriously affected by air pollution. In this study, yield of winter wheat (Triticum aestivum L.) was analyzed with respect to the potential impact of air pollution index under conditions of optimal crop management in the NCP from 2001 to 2012. Results showed that air pollution was especially serious at the early phase of winter wheat growth significantly influencing various weather factors. However, no significant correlations were found between final grain yield and the weather factors during the early growth phase. In contrast, significant correlations were found between grain yield and total solar radiation gap, sunshine hour gap, diurnal temperature range and relative humidity during the late growing phase. To disentangle the confounding effects of various weather factors, and test the isolated effect of air pollution induced changes in incoming global solar radiation on yield under ceteris paribus conditions, crop model based scenario-analysis was conducted. The simulation results of the calibrated Agricultural Production Systems Simulator (APSIM) model indicated that a reduction in radiation by 10% might cause a yield reduction by more than 10%. Increasing incident radiation by 10% would lead to yield increases of (only) 7%, with the effects being much stronger during the late growing phase compared to the early growing phase. However, there is evidence that APSIM overestimates the effect of air pollution induced changes on radiation, as it does not consider the changes in radiative properties of solar insulation, i.e. the relative increase of diffuse over direct radiation, which may partly alleviate the negative effects of reduced total radiation by air pollution. Concluding, the present study could not detect a significantly negative effect of air pollution on wheat yields in the NCP., Competing Interests: The authors have declared that no competing interests exist.

Overuse of nitrogen (N) fertilizer constitutes the major issue of current crop production in China, exerting a substantial effect on global warming through massive emission of greenhouse gas (GHG). Despite the ongoing effort, which includes the promotion of technologically sophisticated N management schemes, farmers' N rates maintain at excessive rates. Therefore the current study tests three simple and easily to apply N fertilizer recommendation strategies, which could be implemented on large scale through the existing agricultural advisory system of China, at comparatively low cost. Building on a detailed crop production dataset of 65 winter wheat (WW) and summer maize (SM) producing farm households of the North China Plain, scenario analysis is applied. The effects of the three N strategies under constant and changing yield levels on product carbon footprint (PCF) and gross margin (GM) are determined for the production condition of every individual farm household. The N fixed rate strategy realized the highest improvement potential in PCF and GM in WW; while the N coefficient strategy performed best in SM. The analysis furthermore revealed that improved N management has a significant positive effect on PCF, but only a marginal and insignificant effect on GM. On the other side, a potential 10% yield loss would have only a marginal effect on PCF, but a detrimental effect on farmers' income. With farmers currently applying excessive N rates as "cheap insurance" against potential N limitation, it will be of vital importance to avoid any yield reductions (caused by N limitation) and respective severe financial losses, when promoting and implementing advanced fertilization strategies. To achieve this, it is furthermore recommended to increase the price of fertilizer, improve the agricultural extensions system, and recognize farmers' fertilizer related decision-making processes as key research areas., (Copyright © 2015 Elsevier Ltd. All rights reserved.)