Soil nitrogen(N)is the main limiting nutrient for plant growth,which is sensitive to variations in the soil oxygen environment.To provide insights into plant N accumulation and yield under aerated and drip irrigation,...Soil nitrogen(N)is the main limiting nutrient for plant growth,which is sensitive to variations in the soil oxygen environment.To provide insights into plant N accumulation and yield under aerated and drip irrigation,a greenhouse tomato experiment was conducted with six treatments,including three fertilization types:inorganic fertilizer(NPK);organic fertilizer(OM);chemical(75%of applied N)+organic fertilizer(25%)(NPK+OM)under drip irrigation(DI)and aerated irrigation(AI)methods.Under Al,total soil carbon mineralization(C_(min))was significantly higher(by 5.7-7.0%)than under DI irrigation.C_(min)in the fertilizer treatments followed the order NPK+OM>OM>NPK under both AI and DI.Potentially mineralizable C(C_(0))and N(N_(0))was greater under AI than under DI.Gross N mineralization,gross nitrification,and NH_(4)^(+)immobilization rates were significantly higher under the AINPK treatment than the DINPK treatment by 2.58-3.27-,1.25-1.44-,and 1-1.26-fold,respectively.These findings demonstrated that AI and the addition of organic fertilizer accelerated the turnover of soil organic matter and N transformation processes,thereby enhancing N availability.Moreover,the combination of AI and organic fertilizer application was found to promote root growth(8.4-10.6%),increase the duration of the period of rapid N accumulation(ΔT),and increase the maximum N accumulation rate(V_(max)),subsequently encouraging aboveground dry matter accumulation.Consequently,the AI treatment yield was significantly greater(by 6.3-12.4%)than under the DI treatment.Further,N partial factor productivity(NPFP)and N harvest index(NHI)were greater under AI than under DI,by 6.3 to 12.4%,and 4.6 to 8.1%,respectively.The rankings of yield and NPFP remained consistent,with NPK+OM>OM>NPK under both AI and DI treatments.These results highlighted the positive impacts of AI and organic fertilizer application on soil N availability,N uptake,and overall crop yield in tomato.The optimal management measure was identified as the AINPK+OM treatment,which led to more efficient N management,better crop growth,higher yield,and more sustainable agricultural practices.展开更多
Aerated drip irrigation(ADI)is an important practice for promoting soil fertility and crop productivity in greenhouse vegetable production,yet little research has comprehensively investigated its effects on the functi...Aerated drip irrigation(ADI)is an important practice for promoting soil fertility and crop productivity in greenhouse vegetable production,yet little research has comprehensively investigated its effects on the functional traits of carbon(C)-cycling microorganisms.In this study,we sought to assess the potential efficacy of ADI in increasing soil organic C(SOC)by changing soil microbial communities and the expressions of genes associated with C cycling.To this end,we adopted a metagenomic approach to compare the effects of ADI with three dissolved oxygen concentrations(10,15,and 20 mg L^(-1))during a three-season tomato cultivation experiment in northern China.The results revealed that the 10 mg L^(-1)treatment led to a significant increase in the abundance of korA/B genes(associated with the reductive tricarboxylic acid cycle)in the C fixation pathway,whereas the 15 mg L^(-1)treatment increased the abundances of cbbL/R and coxL/S genes associated with the Calvin cycle and carbon monoxide oxidation,respectively.In addition,based on a co-occurrence network analysis,we observed a positive correlation between cbbL and coxS.Interestingly,r-selected microorganisms,such as Proteobacteria and Actinobacteria,characterized by rapid cell multiplication and high biomass production,were identified as the primary contributors to C fixation and were the main predictors of SOC pools.In contrast,the 20 mg L^(-1)treatment was found to adversely influence C fixation,although the enhanced C degradation could be attributed to the extracellular enzymes secreted by K-selected microorganisms.Collectively,our findings indicate that ADI with dissolved oxygen concentrations 15 mg L^(-1)can promote SOC content by altering the life history strategies of r-selected microorganisms and genes associated with C fixation.These findings will provide valuable references for agroecosystem irrigation management,help improve soil fertility,and promote sustainable production.展开更多
Ridge-furrow film mulching has been widely used as a water-saving and yield-increasing planting pattern in arid and semiarid regions.Planting density is also a vitally important factor influencing crop yield,and the o...Ridge-furrow film mulching has been widely used as a water-saving and yield-increasing planting pattern in arid and semiarid regions.Planting density is also a vitally important factor influencing crop yield,and the optimal planting density will vary in different environments(such as ridge-furrow film mulching).How the combination of film mulching and planting density will affect the growth,physiology,yield,and water and radiation use efficiencies of winter oilseed rape is not clear yet.Therefore,a three-year field experiment was conducted from 2017 to 2020 to explore the responses of leaf chlorophyll(Chl)content,net photosynthetic rate(P_(n)),leaf area index(LAI),aboveground dry matter(ADM),root growth and distribution,yield,evapotranspiration(ET),water use efficiency(WUE),and radiation use efficiency(RUE)of winter oilseed rape to different film mulching patterns(F,ridge-furrow planting with plastic film mulching over the ridges;N,flat planting without mulching)and planting densities(LD,100,000 plants ha^(-1);MD,150,000 plants ha^(-1);HD,200,000 plants ha^(-1)).The results showed that the F treatments led to significantly greater leaf Chl contents,P_(n),LAI,and ADM,and a stronger root system than treatments without film mulching throughout the whole winter rapeseed growing seasons.Winter oilseed rape in the MD treatments had better physiological(leaf Chl contents and P_(n))and growth(LAI,ADM,taproot,and lateral root)conditions than in LD and HD at the late growth period after stem-elongation.Grain yield in FMD was the greatest,and it was significantly greater by 34.8-46.0%,6.7-9.6%,87.8-108.3%,38.7-50.3%,and 50.2-61.8%compared to those of FLD,FHD,NLD,NMD,and NHD,respectively.Furthermore,the ET in FMD was equivalent to FLD and FHD,but was markedly lower by 12.2-18.4%,14.5-20.3%,and 14.6-20.4%than in NLD,NMD,and NHD.Finally,the WUE and RUE in FMD were significantly improved by 88.5-94.0%and 29.0-41.8%compared to NHD(the local conventional planting pattern and planting density for winter rapeseed).In summary,FMD is a favorable cultivation management strategy to save water,increase yield and improve resource utilization efficiencies in winter oilseed rape in Northwest China.展开更多
In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge m...In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter wheat.Based on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral UAV.Four machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried out.The results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth status.The accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of 6.53.Spectral purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral purification.The results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching.展开更多
基金supported by the National Natural Science Foundation of China for Young Scholars(52109066)the Postdoctoral Science Foundation of Shaanxi Province,China(2023BSHTBZZ29)the China Postdoctoral Science Foundation(2022M712604 and 2023T160534).
文摘Soil nitrogen(N)is the main limiting nutrient for plant growth,which is sensitive to variations in the soil oxygen environment.To provide insights into plant N accumulation and yield under aerated and drip irrigation,a greenhouse tomato experiment was conducted with six treatments,including three fertilization types:inorganic fertilizer(NPK);organic fertilizer(OM);chemical(75%of applied N)+organic fertilizer(25%)(NPK+OM)under drip irrigation(DI)and aerated irrigation(AI)methods.Under Al,total soil carbon mineralization(C_(min))was significantly higher(by 5.7-7.0%)than under DI irrigation.C_(min)in the fertilizer treatments followed the order NPK+OM>OM>NPK under both AI and DI.Potentially mineralizable C(C_(0))and N(N_(0))was greater under AI than under DI.Gross N mineralization,gross nitrification,and NH_(4)^(+)immobilization rates were significantly higher under the AINPK treatment than the DINPK treatment by 2.58-3.27-,1.25-1.44-,and 1-1.26-fold,respectively.These findings demonstrated that AI and the addition of organic fertilizer accelerated the turnover of soil organic matter and N transformation processes,thereby enhancing N availability.Moreover,the combination of AI and organic fertilizer application was found to promote root growth(8.4-10.6%),increase the duration of the period of rapid N accumulation(ΔT),and increase the maximum N accumulation rate(V_(max)),subsequently encouraging aboveground dry matter accumulation.Consequently,the AI treatment yield was significantly greater(by 6.3-12.4%)than under the DI treatment.Further,N partial factor productivity(NPFP)and N harvest index(NHI)were greater under AI than under DI,by 6.3 to 12.4%,and 4.6 to 8.1%,respectively.The rankings of yield and NPFP remained consistent,with NPK+OM>OM>NPK under both AI and DI treatments.These results highlighted the positive impacts of AI and organic fertilizer application on soil N availability,N uptake,and overall crop yield in tomato.The optimal management measure was identified as the AINPK+OM treatment,which led to more efficient N management,better crop growth,higher yield,and more sustainable agricultural practices.
基金financially supported by the National Natural Science Foundation of China(Nos.52379048 and 52079112)the Key Research and Development Program of Shaanxi Province,China(No.2022ZDLNY03-03)the Major Science and Technology Engineering Innovation Project of Shandong Province,China(No.2020CXGC 010808)。
文摘Aerated drip irrigation(ADI)is an important practice for promoting soil fertility and crop productivity in greenhouse vegetable production,yet little research has comprehensively investigated its effects on the functional traits of carbon(C)-cycling microorganisms.In this study,we sought to assess the potential efficacy of ADI in increasing soil organic C(SOC)by changing soil microbial communities and the expressions of genes associated with C cycling.To this end,we adopted a metagenomic approach to compare the effects of ADI with three dissolved oxygen concentrations(10,15,and 20 mg L^(-1))during a three-season tomato cultivation experiment in northern China.The results revealed that the 10 mg L^(-1)treatment led to a significant increase in the abundance of korA/B genes(associated with the reductive tricarboxylic acid cycle)in the C fixation pathway,whereas the 15 mg L^(-1)treatment increased the abundances of cbbL/R and coxL/S genes associated with the Calvin cycle and carbon monoxide oxidation,respectively.In addition,based on a co-occurrence network analysis,we observed a positive correlation between cbbL and coxS.Interestingly,r-selected microorganisms,such as Proteobacteria and Actinobacteria,characterized by rapid cell multiplication and high biomass production,were identified as the primary contributors to C fixation and were the main predictors of SOC pools.In contrast,the 20 mg L^(-1)treatment was found to adversely influence C fixation,although the enhanced C degradation could be attributed to the extracellular enzymes secreted by K-selected microorganisms.Collectively,our findings indicate that ADI with dissolved oxygen concentrations 15 mg L^(-1)can promote SOC content by altering the life history strategies of r-selected microorganisms and genes associated with C fixation.These findings will provide valuable references for agroecosystem irrigation management,help improve soil fertility,and promote sustainable production.
基金supported by the National Natural Science Foundation of China(52479049 and 51909221)the National Key R&D Program of China(2021YFD1900700)+1 种基金the Key R&D Program of Shaanxi Province,China(2024NC-ZDCYL-02-08)the Key Laboratory of Crop Water Use and Regulation,Ministry of Agriculture and Rural Affairs,China(IFI-CWUR202402).
文摘Ridge-furrow film mulching has been widely used as a water-saving and yield-increasing planting pattern in arid and semiarid regions.Planting density is also a vitally important factor influencing crop yield,and the optimal planting density will vary in different environments(such as ridge-furrow film mulching).How the combination of film mulching and planting density will affect the growth,physiology,yield,and water and radiation use efficiencies of winter oilseed rape is not clear yet.Therefore,a three-year field experiment was conducted from 2017 to 2020 to explore the responses of leaf chlorophyll(Chl)content,net photosynthetic rate(P_(n)),leaf area index(LAI),aboveground dry matter(ADM),root growth and distribution,yield,evapotranspiration(ET),water use efficiency(WUE),and radiation use efficiency(RUE)of winter oilseed rape to different film mulching patterns(F,ridge-furrow planting with plastic film mulching over the ridges;N,flat planting without mulching)and planting densities(LD,100,000 plants ha^(-1);MD,150,000 plants ha^(-1);HD,200,000 plants ha^(-1)).The results showed that the F treatments led to significantly greater leaf Chl contents,P_(n),LAI,and ADM,and a stronger root system than treatments without film mulching throughout the whole winter rapeseed growing seasons.Winter oilseed rape in the MD treatments had better physiological(leaf Chl contents and P_(n))and growth(LAI,ADM,taproot,and lateral root)conditions than in LD and HD at the late growth period after stem-elongation.Grain yield in FMD was the greatest,and it was significantly greater by 34.8-46.0%,6.7-9.6%,87.8-108.3%,38.7-50.3%,and 50.2-61.8%compared to those of FLD,FHD,NLD,NMD,and NHD,respectively.Furthermore,the ET in FMD was equivalent to FLD and FHD,but was markedly lower by 12.2-18.4%,14.5-20.3%,and 14.6-20.4%than in NLD,NMD,and NHD.Finally,the WUE and RUE in FMD were significantly improved by 88.5-94.0%and 29.0-41.8%compared to NHD(the local conventional planting pattern and planting density for winter rapeseed).In summary,FMD is a favorable cultivation management strategy to save water,increase yield and improve resource utilization efficiencies in winter oilseed rape in Northwest China.
基金This study was funded by the National Key R&D Program of China(2021YFD1900700)the National Natural Science Foundation of China(51909221)the China Postdoctoral Science Foundation(2020T130541 and 2019M650277).
文摘In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter wheat.Based on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral UAV.Four machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried out.The results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth status.The accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of 6.53.Spectral purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral purification.The results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching.
