Nitrous oxide(N_(2)O)emissions pose a serious environmental problem when nitrogen(N)fertilizer is excessively applied to plantation systems to enhance tree growth.Although biochar can improve soil fertility and mitiga...Nitrous oxide(N_(2)O)emissions pose a serious environmental problem when nitrogen(N)fertilizer is excessively applied to plantation systems to enhance tree growth.Although biochar can improve soil fertility and mitigate soil N losses,our understanding of its interaction with N fertilizer and its long-term effects remains limited owing to experimental constraints.In this study,two microcosm incubation experiments were performed to evaluate the effect of fresh biochar,compared to 8-year field-aged biochar application in a poplar plantation,on soil N_(2)O emissions triggered by biogas slurry application.The experiments incorporated three biochar levels and four biogas slurry application rates,each with three replicates.The results demonstrated that fresh and aged biochar significantly reduced soil cumulative N_(2)O emissions by 31%–61%and 75%–99%,respectively,over 7 d following biogas slurry application.However,these mitigating effects diminished over incubation time.The application of fresh biochar significantly reduced soil available organic carbon and potential denitrification rates,suggesting that it primarily suppressed soil N_(2)O emissions by limiting the supply of electron donors.In contrast,aged biochar had minimal impact on soil available organic carbon and generally enhanced the abundances of bacterial amoA,nirS,nirK,and nosZ genes.This suggests that the aged biochar potentially suppressed soil N_(2)O emissions by promoting complete denitrification.Partial least squares structure equation model(PLS-SEM)analysis corroborated the two different mechanisms regulating the inhibitory influence of fresh and aged biochar on soil N_(2)O emissions.The lower R^(2)of PLS-SEM analysis for aged biochar(R^(2)=0.256)compared to that for fresh biochar(R^(2)=0.798)indicates that other factors,such as biochar properties,potentially affect soil N_(2)O emissions and warrant further investigation.This study highlights the need to evaluate the long-term effect of biochar on soil N_(2)O emissions,owing to the dynamic changes in biochar and soil properties over time.展开更多
Ocean productivity is the foundation of marine food web,which continuously removes atmospheric carbon dioxide and supports life at sea and on land.Spatio-temporal variability of net primary productivity(NPP),sea surfa...Ocean productivity is the foundation of marine food web,which continuously removes atmospheric carbon dioxide and supports life at sea and on land.Spatio-temporal variability of net primary productivity(NPP),sea surface temperature(SST),sea surface salinity(SSS),mixed layer depth(MLD),and euphotic zone depth(EZD) in the northern B ay of Bengal(BoB) during three monsoon seasons were examined in this study based on remote sensing data for the period 2005 to 2020.To compare the NPP distribution between the coastal zones and open BoB,the study area was divided into five zones(Z1-Z5).Results suggest that most productive zones Z2 and Zl are located at the head bay area and are directly influenced by freshwater discharge together with riverine sediment and nutrient loads.Across Z1-Z5,the NPP ranges from 5 315.38 mg/(m^(2)·d) to 346.7 mg/(m^(2)·d)(carbon,since then the same).The highest monthly average NPP of 5 315.38 mg/(m^(2)·d) in February and 5 039.36 mg/(m^(2)·d) in June were observed from Z2,while the lowest monthly average of 346.72 mg/(m^(2)·d) was observed in March from Z4,which is an oceanic zone.EZD values vary from 6-154 m for the study area,and it has an inverse correlation with NPP concentration.EZD is deeper during the summer season and shallower during the wintertime,with a corresponding increase in productivity.Throughout the year,monthly SST shows slight fluctuation for the entire study area,and statistical analysis shows a significant correlation among NPP,and EZD,overall positive between NPP and MLD,whereas no significant correlation among SSS,and SST for the northern BoB.Long-term trends in SST and productivity were significantly po sitive in head bay zones but negatively productive in the open ocean.The findings in this study on the distribution of NPP,SST,SSS,MLD,and EZD and their seasonal variability in five different zones of BoB can be used to further improve the management of marine resources and overall environmental condition in response to climate changes in BoB as they are of utmost relevance to the fisheries for the three bordering countries.展开更多
Background Fiber maturity is a key cotton quality property,and its variability in a sample impacts fiber processing and dyeing performance.Currently,the maturity is determined by using established protocols in laborat...Background Fiber maturity is a key cotton quality property,and its variability in a sample impacts fiber processing and dyeing performance.Currently,the maturity is determined by using established protocols in laboratories under a controlled environment.There is an increasing need to measure fiber maturity using low-cost(in general less than $20000)and small portable systems.In this study,a laboratory feasibility was performed to assess the ability of the shortwave infrared hyperspectral imaging(SWIR HSI)technique for determining the conditioned fiber maturity,and as a comparison,a bench-top commercial and expensive(in general greater than $60000)near infrared(NIR)instrument was used.Results Although SWIR HSI and NIR represent different measurement technologies,consistent spectral characteristics were observed between the two instruments when they were used to measure the maturity of the locule fiber samples in seed cotton and of the well-defined fiber samples,respectively.Partial least squares(PLS)models were established using different spectral preprocessing parameters to predict fiber maturity.The high prediction precision was observed by a lower root mean square error of prediction(RMSEP)(<0.046),higher R_(p)^(2)(>0.518),and greater percentage(97.0%)of samples within the 95% agreement range in the entire NIR region(1000-2500 nm)without the moisture band at 1940 nm.Conclusion SWIR HSI has a good potential for assessing cotton fiber maturity in a laboratory environment.展开更多
BEL1-LIKE HOMEODOMAIN(BLH)proteins are known to function in various plant developmental processes.However,the role of BLHs in regulating plant cell elongation is still unknown.Here,we identify a BLH gene,GhBLH1,that p...BEL1-LIKE HOMEODOMAIN(BLH)proteins are known to function in various plant developmental processes.However,the role of BLHs in regulating plant cell elongation is still unknown.Here,we identify a BLH gene,GhBLH1,that positively regulates fiber cell elongation.Combined transcriptomic and biochemical analyses reveal that GhBLH1 enhances linolenic acid accumulation to promote cotton fiber cell elongation by activating the transcription of GhFAD7A-1 via binding of the POX domain of GhBLH1 to the TGGA cis-element in the GhFAD7A-1 promoter.Knockout of GhFAD7A-1 in cotton significantly reduces fiber length,whereas overexpression of GhFAD7A-1 results in longer fibers.The K2 domain of GhKNOX6 directly interacts with the POX domain of GhBLH1 to form a functional heterodimer,which interferes with the transcriptional activation of GhFAD7A-1 via the POX domain of GhBLH1.Overexpression of GhKNOX6 leads to a significant reduction in cotton fiber length,whereas knockout of GhKNOX6 results in longer cotton fibers.An examination of the hybrid progeny of GhBLH1 and GhKNOX6 transgenic cotton lines provides evidence that GhKNOX6 negatively regulates GhBLH1-mediated cotton fiber elongation.Our results show that the interplay between GhBLH1 and GhKNOX6 modulates regulation of linolenic acid synthesis and thus contributes to plant cell elongation.展开更多
In response to the Deepwater Horizon （DwH） oil spill event in 2010, the Naval Oceanographic Office deployed a nowcast-forecast system covering the Gulf of Mexico and adjacent Caribbean Sea that was designated Americ...In response to the Deepwater Horizon （DwH） oil spill event in 2010, the Naval Oceanographic Office deployed a nowcast-forecast system covering the Gulf of Mexico and adjacent Caribbean Sea that was designated Americas Seas, or AMSEAS, which is documented in this manuscript. The DwH disaster provided a challenge to the application of available ocean-forecast capabilities, and also generated a historically large observational dataset. AMSEAS was evaluated by four complementary efforts, each with somewhat different aims and approaches： a university research consortium within an Integrated Ocean Observing System （IOOS） testbed; a petroleum industry consortium, the Gulf of Mexico 3-D Operational Ocean Forecast System Pilot Prediction Project （GOMEX-PPP）; a British Petroleum （BP） funded project at the Northern Gulf Institute in response to the oil spill; and the Navy itself. Validation metrics are presented in these different projects for water temperature and salinity profiles, sea surface wind, sea surface temperature, sea surface height, and volume transport, for different forecast time scales. The validation found certain geographic and time biases/errors, and small but systematic improvements relative to earlier regional and global modeling efforts. On the basis of these positive AMSEAS validation studies, an oil spill transport simulation was conducted using archived AMSEAS nowcasts to examine transport into the estuaries east of the Mississippi River. This effort captured the influences of Hurricane Alex and a non-tropical cyclone off the Louisiana coast, both of which pushed oil into the western Mississippi Sound, illustrating the importance of the atmospheric influence on oil spills such as DwH.展开更多
基金supported by the Special Funds for Science and Technology Innovation on Carbon Peak Carbon Neutral of Jiangsu Province,China(No.BK20220017)the Natural Science Foundation of China(No.42007090)the National Key Research and Development Program of China(No.2021YFD22004)。
文摘Nitrous oxide(N_(2)O)emissions pose a serious environmental problem when nitrogen(N)fertilizer is excessively applied to plantation systems to enhance tree growth.Although biochar can improve soil fertility and mitigate soil N losses,our understanding of its interaction with N fertilizer and its long-term effects remains limited owing to experimental constraints.In this study,two microcosm incubation experiments were performed to evaluate the effect of fresh biochar,compared to 8-year field-aged biochar application in a poplar plantation,on soil N_(2)O emissions triggered by biogas slurry application.The experiments incorporated three biochar levels and four biogas slurry application rates,each with three replicates.The results demonstrated that fresh and aged biochar significantly reduced soil cumulative N_(2)O emissions by 31%–61%and 75%–99%,respectively,over 7 d following biogas slurry application.However,these mitigating effects diminished over incubation time.The application of fresh biochar significantly reduced soil available organic carbon and potential denitrification rates,suggesting that it primarily suppressed soil N_(2)O emissions by limiting the supply of electron donors.In contrast,aged biochar had minimal impact on soil available organic carbon and generally enhanced the abundances of bacterial amoA,nirS,nirK,and nosZ genes.This suggests that the aged biochar potentially suppressed soil N_(2)O emissions by promoting complete denitrification.Partial least squares structure equation model(PLS-SEM)analysis corroborated the two different mechanisms regulating the inhibitory influence of fresh and aged biochar on soil N_(2)O emissions.The lower R^(2)of PLS-SEM analysis for aged biochar(R^(2)=0.256)compared to that for fresh biochar(R^(2)=0.798)indicates that other factors,such as biochar properties,potentially affect soil N_(2)O emissions and warrant further investigation.This study highlights the need to evaluate the long-term effect of biochar on soil N_(2)O emissions,owing to the dynamic changes in biochar and soil properties over time.
基金The US Department of State for sponsoring undergraduate exchange program。
文摘Ocean productivity is the foundation of marine food web,which continuously removes atmospheric carbon dioxide and supports life at sea and on land.Spatio-temporal variability of net primary productivity(NPP),sea surface temperature(SST),sea surface salinity(SSS),mixed layer depth(MLD),and euphotic zone depth(EZD) in the northern B ay of Bengal(BoB) during three monsoon seasons were examined in this study based on remote sensing data for the period 2005 to 2020.To compare the NPP distribution between the coastal zones and open BoB,the study area was divided into five zones(Z1-Z5).Results suggest that most productive zones Z2 and Zl are located at the head bay area and are directly influenced by freshwater discharge together with riverine sediment and nutrient loads.Across Z1-Z5,the NPP ranges from 5 315.38 mg/(m^(2)·d) to 346.7 mg/(m^(2)·d)(carbon,since then the same).The highest monthly average NPP of 5 315.38 mg/(m^(2)·d) in February and 5 039.36 mg/(m^(2)·d) in June were observed from Z2,while the lowest monthly average of 346.72 mg/(m^(2)·d) was observed in March from Z4,which is an oceanic zone.EZD values vary from 6-154 m for the study area,and it has an inverse correlation with NPP concentration.EZD is deeper during the summer season and shallower during the wintertime,with a corresponding increase in productivity.Throughout the year,monthly SST shows slight fluctuation for the entire study area,and statistical analysis shows a significant correlation among NPP,and EZD,overall positive between NPP and MLD,whereas no significant correlation among SSS,and SST for the northern BoB.Long-term trends in SST and productivity were significantly po sitive in head bay zones but negatively productive in the open ocean.The findings in this study on the distribution of NPP,SST,SSS,MLD,and EZD and their seasonal variability in five different zones of BoB can be used to further improve the management of marine resources and overall environmental condition in response to climate changes in BoB as they are of utmost relevance to the fisheries for the three bordering countries.
基金supported partially by the USDA-ARS Research Project#6054-44000-080-00D.
文摘Background Fiber maturity is a key cotton quality property,and its variability in a sample impacts fiber processing and dyeing performance.Currently,the maturity is determined by using established protocols in laboratories under a controlled environment.There is an increasing need to measure fiber maturity using low-cost(in general less than $20000)and small portable systems.In this study,a laboratory feasibility was performed to assess the ability of the shortwave infrared hyperspectral imaging(SWIR HSI)technique for determining the conditioned fiber maturity,and as a comparison,a bench-top commercial and expensive(in general greater than $60000)near infrared(NIR)instrument was used.Results Although SWIR HSI and NIR represent different measurement technologies,consistent spectral characteristics were observed between the two instruments when they were used to measure the maturity of the locule fiber samples in seed cotton and of the well-defined fiber samples,respectively.Partial least squares(PLS)models were established using different spectral preprocessing parameters to predict fiber maturity.The high prediction precision was observed by a lower root mean square error of prediction(RMSEP)(<0.046),higher R_(p)^(2)(>0.518),and greater percentage(97.0%)of samples within the 95% agreement range in the entire NIR region(1000-2500 nm)without the moisture band at 1940 nm.Conclusion SWIR HSI has a good potential for assessing cotton fiber maturity in a laboratory environment.
基金supported by the National Natural Science Foundation of China(32070549,32270578,and 32200444)the National Key Research and Development Program of China(SQ2022YFF1000028)+3 种基金the China Postdoctoral Science Foundation(2022M712005)the Natural Science Basic Research Plan in the Shaanxi Province of China(2022JQ-197)the Fundamental Research Funds for the Central Universities(GK202304016,GK202304018,GK202304015)the Xinjiang Production and Construction Corps Key Fields Science and Technology Research Plan(KC00310501).
文摘BEL1-LIKE HOMEODOMAIN(BLH)proteins are known to function in various plant developmental processes.However,the role of BLHs in regulating plant cell elongation is still unknown.Here,we identify a BLH gene,GhBLH1,that positively regulates fiber cell elongation.Combined transcriptomic and biochemical analyses reveal that GhBLH1 enhances linolenic acid accumulation to promote cotton fiber cell elongation by activating the transcription of GhFAD7A-1 via binding of the POX domain of GhBLH1 to the TGGA cis-element in the GhFAD7A-1 promoter.Knockout of GhFAD7A-1 in cotton significantly reduces fiber length,whereas overexpression of GhFAD7A-1 results in longer fibers.The K2 domain of GhKNOX6 directly interacts with the POX domain of GhBLH1 to form a functional heterodimer,which interferes with the transcriptional activation of GhFAD7A-1 via the POX domain of GhBLH1.Overexpression of GhKNOX6 leads to a significant reduction in cotton fiber length,whereas knockout of GhKNOX6 results in longer cotton fibers.An examination of the hybrid progeny of GhBLH1 and GhKNOX6 transgenic cotton lines provides evidence that GhKNOX6 negatively regulates GhBLH1-mediated cotton fiber elongation.Our results show that the interplay between GhBLH1 and GhKNOX6 modulates regulation of linolenic acid synthesis and thus contributes to plant cell elongation.
文摘In response to the Deepwater Horizon （DwH） oil spill event in 2010, the Naval Oceanographic Office deployed a nowcast-forecast system covering the Gulf of Mexico and adjacent Caribbean Sea that was designated Americas Seas, or AMSEAS, which is documented in this manuscript. The DwH disaster provided a challenge to the application of available ocean-forecast capabilities, and also generated a historically large observational dataset. AMSEAS was evaluated by four complementary efforts, each with somewhat different aims and approaches： a university research consortium within an Integrated Ocean Observing System （IOOS） testbed; a petroleum industry consortium, the Gulf of Mexico 3-D Operational Ocean Forecast System Pilot Prediction Project （GOMEX-PPP）; a British Petroleum （BP） funded project at the Northern Gulf Institute in response to the oil spill; and the Navy itself. Validation metrics are presented in these different projects for water temperature and salinity profiles, sea surface wind, sea surface temperature, sea surface height, and volume transport, for different forecast time scales. The validation found certain geographic and time biases/errors, and small but systematic improvements relative to earlier regional and global modeling efforts. On the basis of these positive AMSEAS validation studies, an oil spill transport simulation was conducted using archived AMSEAS nowcasts to examine transport into the estuaries east of the Mississippi River. This effort captured the influences of Hurricane Alex and a non-tropical cyclone off the Louisiana coast, both of which pushed oil into the western Mississippi Sound, illustrating the importance of the atmospheric influence on oil spills such as DwH.
