Long-term straw return with appropriate nitrogen(N)fertilization increases seedcotton yield and fiber quality,and the root system plays an important role in cotton production.However,under straw return and N fertiliza...Long-term straw return with appropriate nitrogen(N)fertilization increases seedcotton yield and fiber quality,and the root system plays an important role in cotton production.However,under straw return and N fertilization,the relationship between the cotton boll-loading capacity of the root system and seedcotton yield remains unclear.In this study,a ten years of long-term field experiment was conducted in a wheat-cotton rotation system.The effects of straw treatments(straw return and straw removal)and N rates(N0,N75,N150 and N300 representing 0,75,150 and 300 kg N ha^(-1),respectively)on cotton root activity,boll-loading capacity of the root system and their relationship to seedcotton yield from 2019 to 2022 were quantified.The results showed that straw return with an appropriate N fertilization of N150 increased root biomass,the rate and components of root-bleeding sap,as well as boll-loading capacity of the root system and seedcotton yield,but decreased the ratio of root to shoot biomass.Furthermore,the root-bleeding sap rate reached the maximum at 30 d post anthesis(DPA)during the peak boll setting stage.However,the contents of nitrate-N,free amino acids and soluble sugar in root-bleeding sap decreased from 10 DPA.Notably,in 2021 and at 30 DPA,the highest contents of nitrate-N(4.8μg mL^(-1))and free amino acids(8.3μg mL^(-1)),as well as soluble sugar(3.4μg mL^(-1))were observed at N150 under straw return.The increase in seedcotton yield is positively correlated to the soluble sugar content.Straw return significantly increased the boll-loading capacity of the root system,which first increased but then decreased with the increase in N fertilization.Under straw return with N150,the maximum seecotton yield(3455-4544 kg ha^(-1))was recorded,and the largest boll loading(49-54 boll 100 g^(-1))and boll capacity(242-292 g 100 g^(-1))of root system at the boll opening stage were observed.Therefore,straw return with appropriate N fertilization improved root activity and the boll-loading capacity of the root system,thereby increasing seedcotton yield.This study provides new insights into improving seedcotton yield from the perspective of coordinating cotton growth.展开更多
The strategy of choosing suitable plants should receive great performance in phytoremediation of surface water polluted by triazophos （O,O-diethyl-O-（1-phenyl- 1,2,4-triazol-3-base） sulfur phosphate, TAP）, which i...The strategy of choosing suitable plants should receive great performance in phytoremediation of surface water polluted by triazophos （O,O-diethyl-O-（1-phenyl- 1,2,4-triazol-3-base） sulfur phosphate, TAP）, which is an organophosphorus pesticide widespread applied for agriculture in China and moderately toxic to higher animal and fish. The tolerance, uptake, transformation and removal of TAP by twelve species of macrophytes were examined in a hydroponic system and a comprehensive score （CS） of five parameters （relative growth rate （RGR）, biomass, root/shoot ratio, removal capacity （RC）, and bio-concentration factor （BCF）） by factor analysis was employed to screen the potential macrophyte species for TAP phytoremediation. The results showed that Thalia dealbata, Cyperus alternifolius, Canna indica and Acorus calamus had higher RGR values, indicating these four species having stronger growth capacity under TAP stress. The higher RC loading in Iris pseudacorus and Cyperus rotundus were 42.11 and 24.63μg/（g fw.day）, respectively. The highest values of BCF occurred in A. calamus （1.17）, and TF occurred in Eichhornia crassipes （2.14）. Biomass and root/shoot ratio of plant showed significant positive correlation with first-order kinetic constant of TAP removal in the hydroponic system, indicating that plant biomass and root system play important roles in remediation of TAP. Five plant species including C. alternifolius, A. calamus, T. dealbata, C. indica and Typha orientalis, which owned higher CS, would be potential species for TAP phytoremediation of contaminated water bodies.展开更多
Root zone maximum water deficit(S_(Rmax))refers to the maximum water consumption of the root zone during drought,which directly influences the partitioning of precipitation between infiltration and runoff.It is a key ...Root zone maximum water deficit(S_(Rmax))refers to the maximum water consumption of the root zone during drought,which directly influences the partitioning of precipitation between infiltration and runoff.It is a key parameter in land surface hydrological modeling.Since the implementation of the Grain-for-Green Project(GFG)on the Loess Plateau(LP),vegetation restoration has achieved significant success,resulting in the“greening”of LP while simultaneously reducing surface runoff.However,the lack of consideration for the root zone,a key link between terrestrial ecological and hydrological processes,has hindered understanding of ecohydrological mechanisms and limited comprehensive assessments of regional water resource management and ecological engineering outcomes.This study analyzes the spatiotemporal dynamic of S_(Rmax)on the LP from 1982 to 2018 using multi-source datasets and the Mass Curve Technique.Additionally,we employ a hybrid machine learningstatistical attribution model to quantify the contributions of land use and climate change to the S_(Rmax) dynamic.The results indicate an average S_(Rmax)of 85.3 mm across the LP,with significant variations among land use types:natural forest(116.3 mm)>planted forest(104.6 mm)>grassland(87.0 mm)>cropland(78.8 mm).Following the implementation of GFG,S_(Rmax)increased by 37.7%,with an upward trend observed across all land use types,particularly in changed land type,which experienced the largest increases.The attribution model achieved a coefficient of determination(R^(2))of 0.92.The key factors driving S_(Rmax) variation varied by land use type:in unchanged land type,climate change accounted for 53.8%of the S_(Rmax)increase,whereas land use change explained 71.3%of the increase in changed land type,with GFG contributing 52.1%.These findings provide a scientific basis for enhancing drought resilience and implementing the“Water-for-Greening”strategy on the LP and similar regions under changing environmental conditions.展开更多
Adaptation of ecosystems'root zones to climate change critically affects drought resilience and vegetation productivity.However,a global quantitative assessment of this mechanism is missing.In this study,we analyz...Adaptation of ecosystems'root zones to climate change critically affects drought resilience and vegetation productivity.However,a global quantitative assessment of this mechanism is missing.In this study,we analyzed high-quality observation-based data to find that the global average root zone water storage capacity(S_(R))increased by 11%,from 182 to 202 mm in 1982-2020.The total increase of Sr equals to 1652 billion m^(3) over the past four decades.S_(R) increased in 9 out of 12 land cover types,while three relatively dry types experienced decreasing trends,potentially suggesting the crossing of ecosystems'tipping points.Our results underscore the importance of accounting for root zone dynamics under climate changetoassessdroughtimpacts.展开更多
The matching relationship between the spatial structure of cotton cluster root systems and soil-wetting patterns under mulched drip irrigation forms the theoretical basis for the technical design of mulched drip irrig...The matching relationship between the spatial structure of cotton cluster root systems and soil-wetting patterns under mulched drip irrigation forms the theoretical basis for the technical design of mulched drip irrigation.A 2-year field experiment was conducted,in which different soil-wetting patterns were produced by setting different emitter discharge rates.The envelopes of cotton cluster root length densities were derived using the topological methodology and used to examine the effects of different soil-wetting patterns on the spatial structure of root systems and water uptake capacity within row spaces.The results showed that the root systems in rows of cotton grown under narrower and deeper soil-wetting patterns exhibited a single-peak distribution,while those under wider and shallower soil-wetting patterns exhibited a two-peak distribution.Furthermore,cotton rows grown near mulch edges experienced lower moisture stress,and wider and shallower soil-wetting patterns contributed to greater root growth rates in the vertical direction and resulted in more even potential water uptake capacities.The findings of this study revealed that wider and shallower soil-wetting patterns were more desirable for mulched drip irrigation of cotton and should be considered in the technical design of drip irrigation systems.展开更多
基金supported by the Jiangsu Agricultural Science and Technology Innovation Fund(CX(22)2015)the Fundamental Research Funds for the Central Universities(XUEKEN2022008)+1 种基金the Innovation Center for Modern Crop Production Cosponsored by Province and Ministry(CIC-MCP)the Cotton Industry Technology Research System of Shandong Province(SDAIT-03).
文摘Long-term straw return with appropriate nitrogen(N)fertilization increases seedcotton yield and fiber quality,and the root system plays an important role in cotton production.However,under straw return and N fertilization,the relationship between the cotton boll-loading capacity of the root system and seedcotton yield remains unclear.In this study,a ten years of long-term field experiment was conducted in a wheat-cotton rotation system.The effects of straw treatments(straw return and straw removal)and N rates(N0,N75,N150 and N300 representing 0,75,150 and 300 kg N ha^(-1),respectively)on cotton root activity,boll-loading capacity of the root system and their relationship to seedcotton yield from 2019 to 2022 were quantified.The results showed that straw return with an appropriate N fertilization of N150 increased root biomass,the rate and components of root-bleeding sap,as well as boll-loading capacity of the root system and seedcotton yield,but decreased the ratio of root to shoot biomass.Furthermore,the root-bleeding sap rate reached the maximum at 30 d post anthesis(DPA)during the peak boll setting stage.However,the contents of nitrate-N,free amino acids and soluble sugar in root-bleeding sap decreased from 10 DPA.Notably,in 2021 and at 30 DPA,the highest contents of nitrate-N(4.8μg mL^(-1))and free amino acids(8.3μg mL^(-1)),as well as soluble sugar(3.4μg mL^(-1))were observed at N150 under straw return.The increase in seedcotton yield is positively correlated to the soluble sugar content.Straw return significantly increased the boll-loading capacity of the root system,which first increased but then decreased with the increase in N fertilization.Under straw return with N150,the maximum seecotton yield(3455-4544 kg ha^(-1))was recorded,and the largest boll loading(49-54 boll 100 g^(-1))and boll capacity(242-292 g 100 g^(-1))of root system at the boll opening stage were observed.Therefore,straw return with appropriate N fertilization improved root activity and the boll-loading capacity of the root system,thereby increasing seedcotton yield.This study provides new insights into improving seedcotton yield from the perspective of coordinating cotton growth.
基金supported by the National Natural Science Foundation of China (No. 20877093, 51278355)
文摘The strategy of choosing suitable plants should receive great performance in phytoremediation of surface water polluted by triazophos （O,O-diethyl-O-（1-phenyl- 1,2,4-triazol-3-base） sulfur phosphate, TAP）, which is an organophosphorus pesticide widespread applied for agriculture in China and moderately toxic to higher animal and fish. The tolerance, uptake, transformation and removal of TAP by twelve species of macrophytes were examined in a hydroponic system and a comprehensive score （CS） of five parameters （relative growth rate （RGR）, biomass, root/shoot ratio, removal capacity （RC）, and bio-concentration factor （BCF）） by factor analysis was employed to screen the potential macrophyte species for TAP phytoremediation. The results showed that Thalia dealbata, Cyperus alternifolius, Canna indica and Acorus calamus had higher RGR values, indicating these four species having stronger growth capacity under TAP stress. The higher RC loading in Iris pseudacorus and Cyperus rotundus were 42.11 and 24.63μg/（g fw.day）, respectively. The highest values of BCF occurred in A. calamus （1.17）, and TF occurred in Eichhornia crassipes （2.14）. Biomass and root/shoot ratio of plant showed significant positive correlation with first-order kinetic constant of TAP removal in the hydroponic system, indicating that plant biomass and root system play important roles in remediation of TAP. Five plant species including C. alternifolius, A. calamus, T. dealbata, C. indica and Typha orientalis, which owned higher CS, would be potential species for TAP phytoremediation of contaminated water bodies.
基金supported by the National Key Research and Development Program of China(Grant Nos.2024YFE0113200,2024YFC3213700)the National Natural Science Foundation of China(Grant Nos.42122002,42471040,and 42071081)。
文摘Root zone maximum water deficit(S_(Rmax))refers to the maximum water consumption of the root zone during drought,which directly influences the partitioning of precipitation between infiltration and runoff.It is a key parameter in land surface hydrological modeling.Since the implementation of the Grain-for-Green Project(GFG)on the Loess Plateau(LP),vegetation restoration has achieved significant success,resulting in the“greening”of LP while simultaneously reducing surface runoff.However,the lack of consideration for the root zone,a key link between terrestrial ecological and hydrological processes,has hindered understanding of ecohydrological mechanisms and limited comprehensive assessments of regional water resource management and ecological engineering outcomes.This study analyzes the spatiotemporal dynamic of S_(Rmax)on the LP from 1982 to 2018 using multi-source datasets and the Mass Curve Technique.Additionally,we employ a hybrid machine learningstatistical attribution model to quantify the contributions of land use and climate change to the S_(Rmax) dynamic.The results indicate an average S_(Rmax)of 85.3 mm across the LP,with significant variations among land use types:natural forest(116.3 mm)>planted forest(104.6 mm)>grassland(87.0 mm)>cropland(78.8 mm).Following the implementation of GFG,S_(Rmax)increased by 37.7%,with an upward trend observed across all land use types,particularly in changed land type,which experienced the largest increases.The attribution model achieved a coefficient of determination(R^(2))of 0.92.The key factors driving S_(Rmax) variation varied by land use type:in unchanged land type,climate change accounted for 53.8%of the S_(Rmax)increase,whereas land use change explained 71.3%of the increase in changed land type,with GFG contributing 52.1%.These findings provide a scientific basis for enhancing drought resilience and implementing the“Water-for-Greening”strategy on the LP and similar regions under changing environmental conditions.
基金supported by the National Key Research and Development Program of China(2024YFF0809304)National Natural Science Foundation of China(42071081)+2 种基金the European Research Council(ERC-2016-ADG-743080,Horizon Europe 101081661)Formas(2022-02089 and 2019-01220)the IKEA Foundation.
文摘Adaptation of ecosystems'root zones to climate change critically affects drought resilience and vegetation productivity.However,a global quantitative assessment of this mechanism is missing.In this study,we analyzed high-quality observation-based data to find that the global average root zone water storage capacity(S_(R))increased by 11%,from 182 to 202 mm in 1982-2020.The total increase of Sr equals to 1652 billion m^(3) over the past four decades.S_(R) increased in 9 out of 12 land cover types,while three relatively dry types experienced decreasing trends,potentially suggesting the crossing of ecosystems'tipping points.Our results underscore the importance of accounting for root zone dynamics under climate changetoassessdroughtimpacts.
基金This study was supported by the National Natural Science Foundation of China(Grant No.51790533(a major project)and No.51709266)the National Key Research and Development Program of China(Grant No.2017YFC0403303)the Central Public-interest Scientific Institution Basal Research Fund(Farmland Irrigation Research Institute,CAAS)(FIRI2016-19 and FIRI2016-16).
文摘The matching relationship between the spatial structure of cotton cluster root systems and soil-wetting patterns under mulched drip irrigation forms the theoretical basis for the technical design of mulched drip irrigation.A 2-year field experiment was conducted,in which different soil-wetting patterns were produced by setting different emitter discharge rates.The envelopes of cotton cluster root length densities were derived using the topological methodology and used to examine the effects of different soil-wetting patterns on the spatial structure of root systems and water uptake capacity within row spaces.The results showed that the root systems in rows of cotton grown under narrower and deeper soil-wetting patterns exhibited a single-peak distribution,while those under wider and shallower soil-wetting patterns exhibited a two-peak distribution.Furthermore,cotton rows grown near mulch edges experienced lower moisture stress,and wider and shallower soil-wetting patterns contributed to greater root growth rates in the vertical direction and resulted in more even potential water uptake capacities.The findings of this study revealed that wider and shallower soil-wetting patterns were more desirable for mulched drip irrigation of cotton and should be considered in the technical design of drip irrigation systems.
