The influence of global climate change on agricultural productivity is an essential issue of ongoing concern. The growth and development of wheat, maize, and rice are influenced by elevated atmospheric CO₂ concentrations, increased temperatures, and seasonal rainfall patterns. However, due to differences in research methodologies (e.g., crop models, climate models, and climate scenarios), there is uncertainty in the existing studies regarding the magnitude and direction of future climate change impacts on crop yields. In order to completely assess the possible consequences of climate change and adaptation measures on crop production and to analyze the associated uncertainties, a database of future crop yield changes was developed using 68 published studies (including 1842 samples). A local polynomial approach was used with the full dataset to investigate the response of crop yield changes to variations in maximum and minimum temperatures, mean temperature, precipitation, and CO₂ concentrations. Then, a linear mixed-effects regression model was utilized with the limited dataset to explore the quantitative relationships between them. It was found that maximum temperature, precipitation, adaptation measure, study area, and climate model had significant effects on changes in crop yield. Crop yield will decline by 4.21% for each 1 °C rise in maximum temperature and increase by 0.43% for each 1% rise in precipitation. While higher CO₂ concentrations and suitable management strategies could mitigate the negative effects of warming temperatures, crop yield with adaptation measures increased by 64.09% compared to crop yield without adaptation measures. Moreover, the uncertainty of simulations can be decreased by using numerous climate models. The results may be utilized to guide policy regarding the influence of climate change and to promote the creation of adaptation plans that will increase crop systems’ resilience in the future.

Fertilizer application is the basis for ensuring high yield, high quality and high efficiency of farmland. In order to meet the demand for food with the increasing of population, the application of nitrogen fertilizer will be further increased, which will lead to problems such as N₂O emission and nitrogen loss from farmland, it will easily deteriorate the soil and water environment of farmland, and will not conducive to the sustainable development of modern agriculture. However, optimizing fertilizer management is an important way to solve this problem. While, due to the differences in the study conditions (geographical location, environmental conditions, experimental design, etc.), leading to the results obtained in the literatures about the N₂O emission with different nitrogen fertilizer application strategies have significant differences, which requiring further comprehensive quantitative analysis. Therefore, we analyzed the effects of nitrogen fertilizer application strategies (different fertilizer types and fertilizer application rates) on N₂O emissions from the fields (rice, wheat and maize) based on the Meta-analysis using 67 published studies (including 1289 comparisons). For the three crops, inorganic fertilizer application significantly increased on-farm N₂O emissions by 19.7–101.05% for all three; and organic fertilizer increased N₂O emissions by 28.16% and 69.44% in wheat and maize fields, respectively, but the application of organic fertilizer in rice field significantly reduced N₂O emissions by 58.1%. The results showed that overall, the application of inorganic fertilizers resulted in higher N₂O emissions from farmland compared to the application of organic fertilizers. In addition, in this study, the average annual temperature, annual precipitation, soil type, pH, soil total nitrogen content, soil organic carbon content, and soil bulk weight were used as the main influencing factors of N₂O emission under nitrogen fertilizer strategies, and the results of the study can provide a reference for the development of integrated management measures to control greenhouse gas emissions from agricultural soils.

A large amount of nitrogen fertilizer is applied in maize planting in Northeast China, but the recovery rate is low, causing a series of water and soil environmental problems in farmland areas. Thus, based on isotope tracing technology and combining a field plot test with an in situ microzone test, we carried out an experiment under reduced nitrogen fertilizer conditions. Five different nitrogen application levels were set: conventional nitrogen application (N1: 250 kg ha⁻¹), 10%-reduced nitrogen fertilizer (N-10: 225 kg ha⁻¹), 20%-reduced nitrogen fertilizer (N-20: 200 kg ha⁻¹), 30%-reduced nitrogen fertilizer (N-30: 175 kg ha⁻¹), and nitrogen-free (N0: 0 kg ha⁻¹) treatments. Yield, nitrogen accumulation in maize and nitrogen fertilizer fates were studied. The results showed that reducing nitrogen application rates improved the recovery rates of basal fertilizer and topdressing. Specifically, the recovery rate of basal fertilizer was 19.81–26.20%, and the recovery rate of topdressing was 40.24–47.71%. The loss rate of basal fertilizer was 19.96–39.18%, and nitrogen reduction decreased the loss rate of basal fertilizer. The loss rate of topdressing ranged from 36.46 to 41.76%. The residual rates of basal fertilizer and topdressing in the 0–100 cm soil layer were 41.01–53.84% and 12.22–22.30%, respectively. As the nitrogen application rate decreased, corn yield and nitrogen accumulation in maize decreased. Reductions of 20% and 30% in nitrogen fertilizer had a negative influence on plant nitrogen accumulation. This experiment revealed the effect of reducing nitrogen fertilizer application rates on the fate of nitrogen fertilizer, maize yield and nitrogen accumulation in Northeast China. In Northeast China, reducing the nitrogen fertilizer application rate could increase the nitrogen fertilizer recovery rate and reduce nitrogen fertilizer loss amounts and the risk of environmental pollution, but reduce maize yield.

Efficient utilization of light and heat resources is an important part of cleaner production. However, exploring the changes in light and heat resources utilization potential in paddy under future climate change is essential to make full use of the potential of rice varieties and ensure high-efficient, high-yield, and high-quality rice production, which has been seldom conducted. In our study, a process-based crop model (CERES-Rice) was calibrated and validated based on experiment data from the Songnen Plain of China, and then driven by multiple global climate models (GCMs) from the coupled model inter-comparison project (CMIP6) to predict rice growth period, yield, and light and heat resources utilization efficiency under future climate change conditions. The results indicated that the rice growth period would be shortened, especially in the high emission scenario (SSP585), while rice yield would increase slightly under the low and medium emission scenarios (SSP126 and SSP245), it decreased significantly under the high emission scenario (SSP585) in the long term (the 2080s) relative to the baseline of 2000–2019. The light and temperature resources utilization (E_RT), light utilization efficiency (E_R), and heat utilization efficiency (HUE) were selected as the light and heat resources utilization evaluation indexes. Compared with the base period, the mean E_RT in the 2040s, 2060s, and 2080s were −6.46%, −6.01%, and −6.03% under SSP126, respectively. Under SSP245, the mean E_RT were −7.89%, −8.41%, and −8.27%, respectively. Under SSP585, the mean E_RT were −6.88%, −13.69%, and −28.84%, respectively. The E_R would increase slightly, except for the 2080s under the high emission scenario. Moreover, the HUE would reduce as compared with the base period. The results of the analysis showed that the most significant meteorological factor affecting rice growth was temperature. Furthermore, under future climate conditions, optimizing the sowing date could make full use of climate resources to improve rice yield and light and heat resource utilization indexes, which is of great significance for agricultural cleaner production in the future.