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【Objective】 Study on the spatial and temporal variability in water demand of processing tomato in the Northwest Arid Region of China is very essential for local agricultural water management and optimal allocation. 【Method】 Based on the meteorological data measured from 40 weather stations in 1985—2014 within the study region, the evapotranspiration (ETc) and irrigation water demand (Ic) were calculated for the processing tomato, using the modified crop coefficients and water balance equation. 【Result】 Spatially from the west to the east, the ETc and Ic of the processing tomato during different growing stages increased first and then decreased, with its value peaking in eastern Xinjiang, Gansu and Northwestern Ningxia and Inner Mongolia. The annual average ETc during the growing period of the tomato in Xinjiang, Gansu, Ningxia and Inner Mongolia were 460.98-1 202.69 mm, 591.14-749.92 mm, and 530.63-878.66 mm, respectively. Meanwhile, the annual average Ic in these three regions were 187.21-1 180.98 mm, 508.69-702.97 mm, and 354.94-851.14 mm, respectively. On the time scale of 30 years, the ETc and Ic in tomato growing period increased at a rate ranging from 0 to 30.0 mm/10 a. In particular, the ETc in Xinjiang and Gansu showed a significant increase, while the ETc in Ningxia and Inner Mongolia increased insignificantly. Additionally, the trend of average Ic in Ningxia and Inner Mongolia was not obvious. 【Conclusion】 The ETc and Ic over whole growing period of processing tomato in the study region showed strong spatial and temporal variability, and there is an urgent need to implement water-saving irrigation technology and strengthen the optimal allocation of water resources under the environment of climate change.

Accurate identification of the spatio-temporal planting structure and analysis of its driving factors in an irrigation district are the important bases for scientific and reasonable utilization of irrigation water resources. In pursuit of this goal, the training sample migration method combined with the random forest algorithm were used to classify land use and planting structure over 2001–2022 in the lower Yellow River Basin. Moreover, an econometric regression model was applied to quantify the driving factors of the change in the crop-planted area. The results illustrated that the identification method has relatively high accuracy in identifying historical periods of land use and planting structures, with the average kappa coefficient equating to 0.953. From 2001 to 2022, the area of cultivated land was the largest, with the proportion of the total area increasing from 45.72% to 58.12%. The planted area of winter wheat–summer maize rotation increased from 74.84% to 88.11% of the cultivated land. While the planted area of cotton declined by 96.36%, about 50% of cotton planting was converted to the winter wheat–summer maize rotation planting. The government policies about grain purchase and storage were the dominant factors for the change in the crop-planted area. This resulted in an increase of 63.32 × 103 ha and 63.98 × 103 ha in the planted area of winter wheat and summer maize, respectively. The findings are of great significance to the allocation of water resources in irrigation districts of the lower Yellow River Basin. [ABSTRACT FROM AUTHOR]

Background and Aims: Elevated carbon dioxide (eCO2) is known to enhance biomass accumulation and plant growth by improving photosynthesis and promoting stomatal closure. However, the effects of CO2 fertilization on aboveground and belowground biomass differ significantly among crops, which may influence agricultural productivity and carbon storage in plants and soils. This study aims to quantify impacts of eCO2 on crop yield and biomass and to identify the key factors influencing crop yield responses.This study analyzed the biomass changes in response to eCO2 and its impacts on agricultural yields dedicated to major crops, i.e., maize, rice, and wheat, using a meta-analysis method based on 757 pairs of global observations from 178 peer-reviewed articles.The results indicated that eCO2 increased the yields of maize, rice, and wheat by approximately 12%, 17% and 22%, respectively. Variation in biomass accounted for 39%, 28% and 43% of the yield response in these three crops, respectively. In maize and rice, the non-yield components of the aboveground biomass posed direct effects and acted as mediating variables, whereas in rice, the belowground biomass was more influential.The present findings revealed the dominant role of various biomass components in determining the impact of eCO2 on agricultural productivity. In rice, belowground biomass was identified as the most significant factor affecting the yield response to CO2 fertilization. For maize and wheat, the non-yielding fraction of the aboveground biomass was the most important factor.Methods: Elevated carbon dioxide (eCO2) is known to enhance biomass accumulation and plant growth by improving photosynthesis and promoting stomatal closure. However, the effects of CO2 fertilization on aboveground and belowground biomass differ significantly among crops, which may influence agricultural productivity and carbon storage in plants and soils. This study aims to quantify impacts of eCO2 on crop yield and biomass and to identify the key factors influencing crop yield responses.This study analyzed the biomass changes in response to eCO2 and its impacts on agricultural yields dedicated to major crops, i.e., maize, rice, and wheat, using a meta-analysis method based on 757 pairs of global observations from 178 peer-reviewed articles.The results indicated that eCO2 increased the yields of maize, rice, and wheat by approximately 12%, 17% and 22%, respectively. Variation in biomass accounted for 39%, 28% and 43% of the yield response in these three crops, respectively. In maize and rice, the non-yield components of the aboveground biomass posed direct effects and acted as mediating variables, whereas in rice, the belowground biomass was more influential.The present findings revealed the dominant role of various biomass components in determining the impact of eCO2 on agricultural productivity. In rice, belowground biomass was identified as the most significant factor affecting the yield response to CO2 fertilization. For maize and wheat, the non-yielding fraction of the aboveground biomass was the most important factor.Results: Elevated carbon dioxide (eCO2) is known to enhance biomass accumulation and plant growth by improving photosynthesis and promoting stomatal closure. However, the effects of CO2 fertilization on aboveground and belowground biomass differ significantly among crops, which may influence agricultural productivity and carbon storage in plants and soils. This study aims to quantify impacts of eCO2 on crop yield and biomass and to identify the key factors influencing crop yield responses.This study analyzed the biomass changes in response to eCO2 and its impacts on agricultural yields dedicated to major crops, i.e., maize, rice, and wheat, using a meta-analysis method based on 757 pairs of global observations from 178 peer-reviewed articles.The results indicated that eCO2 increased the yields of maize, rice, and wheat by approximately 12%, 17% and 22%, respectively. Variation in biomass accounted for 39%, 28% and 43% of the yield response in these three crops, respectively. In maize and rice, the non-yield components of the aboveground biomass posed direct effects and acted as mediating variables, whereas in rice, the belowground biomass was more influential.The present findings revealed the dominant role of various biomass components in determining the impact of eCO2 on agricultural productivity. In rice, belowground biomass was identified as the most significant factor affecting the yield response to CO2 fertilization. For maize and wheat, the non-yielding fraction of the aboveground biomass was the most important factor.Conclusion: Elevated carbon dioxide (eCO2) is known to enhance biomass accumulation and plant growth by improving photosynthesis and promoting stomatal closure. However, the effects of CO2 fertilization on aboveground and belowground biomass differ significantly among crops, which may influence agricultural productivity and carbon storage in plants and soils. This study aims to quantify impacts of eCO2 on crop yield and biomass and to identify the key factors influencing crop yield responses.This study analyzed the biomass changes in response to eCO2 and its impacts on agricultural yields dedicated to major crops, i.e., maize, rice, and wheat, using a meta-analysis method based on 757 pairs of global observations from 178 peer-reviewed articles.The results indicated that eCO2 increased the yields of maize, rice, and wheat by approximately 12%, 17% and 22%, respectively. Variation in biomass accounted for 39%, 28% and 43% of the yield response in these three crops, respectively. In maize and rice, the non-yield components of the aboveground biomass posed direct effects and acted as mediating variables, whereas in rice, the belowground biomass was more influential.The present findings revealed the dominant role of various biomass components in determining the impact of eCO2 on agricultural productivity. In rice, belowground biomass was identified as the most significant factor affecting the yield response to CO2 fertilization. For maize and wheat, the non-yielding fraction of the aboveground biomass was the most important factor. [ABSTRACT FROM AUTHOR]

Soil salinization leads to significant changes in microbial communities and ecological functions, but their resistance and resilience to salinity stress are not well understood. In this study, we analyzed changes in bacterial community and ecological functions, i.e., CO 2 and N 2 O emissions, under NaCl and Na 2 SO 4 stresses, as well as after the removal of these stresses. The results showed that slight to severe NaCl and Na 2 SO 4 stresses significantly increased alpha diversity of bacterial community and altered the structure of bacterial community. In contrast, NaCl and Na 2 SO 4 stresses both linearly reduced CO 2 and N 2 O emissions, with NaCl stress exhibiting a greater suppression effect than Na 2 SO 4 stress. After salinity leaching, the bacterial community traits-diversity, richness, complexity, and stability-generally recovered, with stronger recovery observed under greater salinity stress. However, the structure of bacterial community did not recover, even for those subjected to slight NaCl and Na 2 SO 4 stresses. The CO 2 and N 2 O emission fluxes recovered in the late stage of the recovery period, particularly in the treatments that experienced moderate NaCl and severe Na 2 SO 4 stresses. Additionally, the CO 2 and N 2 O emissions were mainly dominated by the salinity-sensitive subcommunity. Generally, salinity leaching shifted the microbial community to an alternative state but facilitated the recovery of microbial diversity, complexity, stability, and functions. The findings provided implications for the management and reclamation of saline-alkali farmland., (Copyright © 2024. Published by Elsevier B.V.)