Free economic zone (FEZ) has a long history and plays a more and more important role in the world economy. Most studies, however, focused on the theoretical analysis of benefit and cost as well as the economic role of...Free economic zone (FEZ) has a long history and plays a more and more important role in the world economy. Most studies, however, focused on the theoretical analysis of benefit and cost as well as the economic role of FEZ in the less developed countries and little attention has been paid to the evolution of FEZ. This paper will improve the above-mentioned studies and put forward the structural and spatial evolutionary model of FEZ by analyzing the development of objectives, preferential policy, governance structure, industrial sectors and location of FEZs based on the international economic and political development. FEZs develop towards: 1) more comprehensive and macro objectives, 2) more industry-oriented and multi-preferential policies, 3) more cross-national and combination zones with administrative areas, 4) more technology-intensive and multi-industries, 5) more flexible location and larger spatial dimensions, 6) more rapid evolution and typologies, and 7) more economic integration to the host economy.展开更多
Background:The aim of the study was to investigate the changes in the periarterial capillary-free zone(paCFZ)after anti-vascular endothelial growth factor(VEGF)therapy in patients with branch retinal vein occlusion(BR...Background:The aim of the study was to investigate the changes in the periarterial capillary-free zone(paCFZ)after anti-vascular endothelial growth factor(VEGF)therapy in patients with branch retinal vein occlusion(BRVO)by widefield swept-source optical coherence tomography angiography(SS-OCTA)and assess their associations with clinical outcomes.Methods:In this retrospective observational study of 54 treatment-naive BRVO patients with macular edema,we reviewed the findings of 12×12 mm^(2)SS-OCTA at baseline,3,6,and 12 months after intravitreal ranibizumab injections.The paCFZ and major retinal artery areas were measured on SS-OCTA images.The paCFZ area to artery area(P/A)ratio was calculated.Results:The paCFZ areas and P/A ratios of first-and second-order arteries were significantly greater in BRVO eyes than in contralateral eyes(all P<0.01),but there were no differences in the first-and second-order artery areas(P=0.20 and 0.25,respectively).The paCFZ areas and P/A ratios decreased significantly at 3,6,and 12 months after anti-VEGF therapy(all P<0.01).The baseline P/A ratio was significantly correlated with the baseline best-corrected visual acuity(BCVA),central retinal thickness,and their improvements at 3,6,and 12 months(all P<0.05).Baseline BCVA and P/A ratios of first-and second-order arteries were independently associated with the final BCVA in multivariate linear regression.Conclusions:Wide-field SS-OCTA shows that anti-VEGF therapy can lead to a significant improvement in the paCFZ parameters in BRVO.Smaller baseline P/A ratios on SS-OCTA tend to predict better visual outcomes at 12 months after anti-VEGF therapy.展开更多
As a new mode for Chinese overseas investment and a growth pole for industrialization and urbanization of the host countries,the overseas economic and trade cooperation zone(OETCZ) or overseas free economic zone(OFEZ)...As a new mode for Chinese overseas investment and a growth pole for industrialization and urbanization of the host countries,the overseas economic and trade cooperation zone(OETCZ) or overseas free economic zone(OFEZ) of China plays an important role under the Belt and Road Initiative.With the rising attention on OETCZ,studies regarding OETCZ have also increased.However,there is a lack of studies reviewing this topic’s progress,challenges and future directions.This paper employs a systematic review to examine the literature on the OETCZ along the Belt and Road,based on domestic and overseas studies.The results show that domestic studies account for a large proportion of the collected literature,compared to overseas studies.Interdisciplinary research focus includes inductive case studies from a classification perspective,deductive studies based on cultural and institutional perspectives,trade network and bilateral trade relations based on the perspectives of international trade and regional economy,spatial planning studies from urban planning perspective,and overseas comments and earlier studies on Japan’s and Singapore’s overseas parks from the geopolitical and international political perspectives.Despite diverse research contents and dramatic progress,limitations exist in current OETCZ-related studies,including a lack of exploration of the mechanism,questions and concerns from overseas scholars,sustainable development and other problems.Future studies should broaden and deepen research insights,including the “overseas free economic zones(OFEZ)” as a general designation to cover all other types of OETCZs,studies on the primary conditions of host countries,exploration of the theoretical issues behind China’s OETCZ,comparative study of OETCZs such as management structures,profit models,environmental standards and legal systems as well as popular issues questioned internationally.展开更多
We propose a simple-to-implement dynamic panel data method to evaluate the impacts of place-based policies.The idea is to exploit both the cross sectional dependence and the serial correlation within a panel and imple...We propose a simple-to-implement dynamic panel data method to evaluate the impacts of place-based policies.The idea is to exploit both the cross sectional dependence and the serial correlation within a panel and implement a semi difference-in-difference decomposition.Different from the method by Hsiao et al.(2012),the proposed model is easy to implement statistical inferences and can incorporate multiple treated groups at different time thresholds.We use the proposed method to explore the effect of the Free Trade Zone(FTZ)policy implemented in Shanghai at the end of 2013 on local GDP growth rate and compare it with that from Hsiao et al.(2012).The empirical results show that the FTZ does have a positive effect on the local GDP growth rate and it adds 1:21:8 percent point to the growth rate of the GDP per capita for Shanghai in 2014 which is about one fourth to one third of the total GDP growth rate per capita.This effect largely comes from the growth of the tertiary sector.The results lend support to the duplication of FTZ policy to other cities and provinces in China.展开更多
The influence of quench transfer time on the microstructure and mechanical properties of 7055 aluminum alloy with and without zirconium was investigated by tensile properties test,optical microscopy,scanning electron ...The influence of quench transfer time on the microstructure and mechanical properties of 7055 aluminum alloy with and without zirconium was investigated by tensile properties test,optical microscopy,scanning electron microscopy and transmission electron microscopy.For the Zr-free alloy,the strength increases to the highest value at 20 s with transfer time,and then decreases slightly.The elongation decreases slowly with transfer time within 20 s,and more rapidly after 20 s.For the Zr-containing alloy,prolonging transfer time within 20 s results in slight decrease in the strength and elongation,and rapid drop of which is observed after 20 s.For the Zr-free alloy,prolonging transfer time can increase the percentage of intergranular fracture,which is mainly caused by wide grain boundary precipitate free zone.The failure mode of the Zr-containing alloy is modified from the predominant transgranular void growth and intergranular fracture to transgranular shear and intergranular fracture with increase in the transfer time,which is attributed to the wider grain boundary precipitate free zone and coarse equilibrium η phases in the matrix.展开更多
Two contents(1.5%and3%)of TiB2nanoparticles were introduced in Al?Mn?Mg3004alloy to study their effects on theelevated-temperature properties.Results show that TiB2nanoparticles were mainly distributed at the interden...Two contents(1.5%and3%)of TiB2nanoparticles were introduced in Al?Mn?Mg3004alloy to study their effects on theelevated-temperature properties.Results show that TiB2nanoparticles were mainly distributed at the interdendritic grain boundarieswith a size range of20?80nm,which is confirmed by transmission electron microscopy(TEM)and X-ray diffraction(XRD).Therefore,the volume fraction of the dispersoid free zones is greatly reduced and the motion of grain boundaries and dislocations isinhibited more effectively at elevated temperature.After peak precipitation heat treatment,the yield strengths in the alloy with3%TiB2addition at room temperature and300°C were increased by20%and13%respectively,while the minimum creep rate at300°Cwas reduced to only1/5of the base alloy free of TiB2,exhibiting a considerable improvement of elevated-temperature properties inAl?Mn?Mg alloys.展开更多
The China free trade zone,crucial for advancing a new open economy,has gained significant attention lately.We analyzed 885 papers from Peking University Core and CSSCI journals(2012-2023)using CiteSpace for visualizat...The China free trade zone,crucial for advancing a new open economy,has gained significant attention lately.We analyzed 885 papers from Peking University Core and CSSCI journals(2012-2023)using CiteSpace for visualization.Our research results indicate that the literature on China’s free trade zone peaked with 171 articles in 2015,and gradually returned to an average of 45 articles per year.The main research focuses in this field include“institutional innovation”,“negative list”,“financial innovation”,“financial openness”,“opening up to the outside world”,and“economic growth”.In addition,cutting-edge analysis indicates that“dual circulation”and“blockchain”are future research trends.The main authors of the literature include Yang Bin,Zhu Xiaolin,Yuan Bo,Li Meng,Zhao Liang,and others.Their affiliated institutions,research institutes,and universities have not yet formed a clear core circle of authors;The top three research institutions with the highest number of publications are the International Trade and Economic Cooperation Research Institute of the Ministry of Commerce,Kaiyuan Law School of Shanghai Jiao Tong University,and the Comprehensive Research Institute of the Free Trade Zone of Sun Yatsen University.This article delves into the current hot topics and progress in the research of China’s free trade zones,providing important references and inspirations for future scholars in this field.展开更多
The composition and concentration of dissolved free amino acid(DFAA)of seawater samples collected in May 2016 from the surface to the hadal zone of the northern region of the Yap Trench were analyzed by pre-column der...The composition and concentration of dissolved free amino acid(DFAA)of seawater samples collected in May 2016 from the surface to the hadal zone of the northern region of the Yap Trench were analyzed by pre-column derivatization of o-phthalaldehyde.Results show that the average concentration of DFAA in the study area was 0.47±0.36μmol/L.In different sampling stations,the concentrations of DFAA with water depth showed complex variation patterns.At the sediment-seawater interface,the concentrations of DFAA in the western side of the trench were obviously higher than that in its eastern side.In the study area,there were no significant correlations between the concentrations of DFAA and the environmental parameters such as concentrations of chlorophyll a(Chl a),dissolved oxygen(DO),pH,and dissolved inorganic nitrogen(DIN),indicating that the concentrations of DFAA in seawater of the trench are affected by many factors,such as photosynthesis,respiration,temperature,pressure,illumination,and circulation.The dominant DFAA are similar in different water layers of sampling stations,including aspartic acid(Asp),glutamic acid(Glu),glycine(Gly),and serine(Ser).The composition of different amino acids,and the relative abundance of acidic,basic,and neutral amino acids might be related to the sources and consumption of various amino acids.Nine pairs of amino acids in the DFAA showed significantly positive relationship by correlation matrix analysis,suggesting that they might share similar biogeochemical processes.The degradation index(DI)of the DFAA in seawater of the Yap Trench could reflect the degradation,source,and freshness of DFAA in the trench to some extents.This is a preliminary study of amino acids from sea surface to hadal zone in the ocean,more works shall be done in different trenches to reveal their biogeochemical characte ristics in extreme marine environme nts.展开更多
Against the backdrop of China's development reality for the time being and upholding the basic logic of boosting the high-quality development of China's economy,the authors give the historical background,reali...Against the backdrop of China's development reality for the time being and upholding the basic logic of boosting the high-quality development of China's economy,the authors give the historical background,realisticclogic,theoretical connotation,and strategic significance of the new development paradigm of dual circulation a thorough interpretation.On this basis,the authors conduct a detailed analysis of the development path between China's Free Trade Zones(FTZs)and the new development paradigm of dual circulation,as well as the new orientation of FTZs under this paradigm.Focusing on systems thinking,the new development paradigm of dual circulation not only opens up a new realm of open economic theory with Chinese characteristics but also enriches the socialist political economy with Chinese characteristics.From the perspective of the new development paradigm of dual circulation,China's FTZs serve as a reform test field and a powerful starting point for driving the high-quality circulation ofChina's economy.From another perspective,it is also an open bridgehead and a significant window for China to participate in international economic circulation.In this sense,China's FTZs remain the key hub linking domestic and international circulations.China's FTZs should be given greater reform autonomy.Whilefocusinggon the differentiated exploration and development models,the dividends of the first trial system should be fully utilized to integrate China's FTZs into the national open development strategy.Thus,high-level open practice can be anticipated to boost the virtuous circle of domestic and foreign economies,with concerted efforts and drive China's economy toward a high-quality future.展开更多
One major consequence of global warming in the Antarctic region is increased ice-free zones.Subsequent colonization of these ice-free areas by penguins alters their biogeochemistry,with one prominent example being ele...One major consequence of global warming in the Antarctic region is increased ice-free zones.Subsequent colonization of these ice-free areas by penguins alters their biogeochemistry,with one prominent example being elevation of inorganic phosphate concentrations around feces depositions.The complex soil biochemistry in the region makes it difficult to define the causal factors of these changes using common research approaches.Here,we addressed the effects of phosphate alone on microbiome structure and dynamics over time by adding external phosphate to selected soils in the Antarctic region.We then analyzed the soil bacterial community composition and diversity using 16S rRNA amplicon sequencing and compared these data with phosphate levels.Parallel geochemical analysis revealed changes in nine soil geochemical factors upon phosphate addition,all of which were relevant to microbiome structure,with soil pH showing the highest correlation.Links between geochemical factors and composition were identified,as were interactions between bacterial taxa.Additionally,Sphingobacteriia,Sphingobacteriales and Chitinophagaceae were found to be more abundant in phosphate-treated soils.Co-occurrence network analysis revealed significantly increased levels of associations in all major network properties over time after phosphate supplementation.Therefore,we conclude phosphate addition has diverse effects on Antarctic soil microbiomes.展开更多
文摘Free economic zone (FEZ) has a long history and plays a more and more important role in the world economy. Most studies, however, focused on the theoretical analysis of benefit and cost as well as the economic role of FEZ in the less developed countries and little attention has been paid to the evolution of FEZ. This paper will improve the above-mentioned studies and put forward the structural and spatial evolutionary model of FEZ by analyzing the development of objectives, preferential policy, governance structure, industrial sectors and location of FEZs based on the international economic and political development. FEZs develop towards: 1) more comprehensive and macro objectives, 2) more industry-oriented and multi-preferential policies, 3) more cross-national and combination zones with administrative areas, 4) more technology-intensive and multi-industries, 5) more flexible location and larger spatial dimensions, 6) more rapid evolution and typologies, and 7) more economic integration to the host economy.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.82101150,82171078)Shanghai clinical 3-year action plan-major clinical research(Grant Nos.SHDC2020CR2041B,SHDC2020CR5014-003)+1 种基金Shanghai Sailing Program(Grant No.21YF1405300)Shanghai Committee of Science and Technology(Grant Nos.20Y11911100,18411965100).
文摘Background:The aim of the study was to investigate the changes in the periarterial capillary-free zone(paCFZ)after anti-vascular endothelial growth factor(VEGF)therapy in patients with branch retinal vein occlusion(BRVO)by widefield swept-source optical coherence tomography angiography(SS-OCTA)and assess their associations with clinical outcomes.Methods:In this retrospective observational study of 54 treatment-naive BRVO patients with macular edema,we reviewed the findings of 12×12 mm^(2)SS-OCTA at baseline,3,6,and 12 months after intravitreal ranibizumab injections.The paCFZ and major retinal artery areas were measured on SS-OCTA images.The paCFZ area to artery area(P/A)ratio was calculated.Results:The paCFZ areas and P/A ratios of first-and second-order arteries were significantly greater in BRVO eyes than in contralateral eyes(all P<0.01),but there were no differences in the first-and second-order artery areas(P=0.20 and 0.25,respectively).The paCFZ areas and P/A ratios decreased significantly at 3,6,and 12 months after anti-VEGF therapy(all P<0.01).The baseline P/A ratio was significantly correlated with the baseline best-corrected visual acuity(BCVA),central retinal thickness,and their improvements at 3,6,and 12 months(all P<0.05).Baseline BCVA and P/A ratios of first-and second-order arteries were independently associated with the final BCVA in multivariate linear regression.Conclusions:Wide-field SS-OCTA shows that anti-VEGF therapy can lead to a significant improvement in the paCFZ parameters in BRVO.Smaller baseline P/A ratios on SS-OCTA tend to predict better visual outcomes at 12 months after anti-VEGF therapy.
基金National Natural Science Foundation of China,No.41971161Tianjin Normal University Interdisciplinary Integration Innovation Team Project,No.135205RH08The Fundamental Research Funds for the Central Universities,No.63232160。
文摘As a new mode for Chinese overseas investment and a growth pole for industrialization and urbanization of the host countries,the overseas economic and trade cooperation zone(OETCZ) or overseas free economic zone(OFEZ) of China plays an important role under the Belt and Road Initiative.With the rising attention on OETCZ,studies regarding OETCZ have also increased.However,there is a lack of studies reviewing this topic’s progress,challenges and future directions.This paper employs a systematic review to examine the literature on the OETCZ along the Belt and Road,based on domestic and overseas studies.The results show that domestic studies account for a large proportion of the collected literature,compared to overseas studies.Interdisciplinary research focus includes inductive case studies from a classification perspective,deductive studies based on cultural and institutional perspectives,trade network and bilateral trade relations based on the perspectives of international trade and regional economy,spatial planning studies from urban planning perspective,and overseas comments and earlier studies on Japan’s and Singapore’s overseas parks from the geopolitical and international political perspectives.Despite diverse research contents and dramatic progress,limitations exist in current OETCZ-related studies,including a lack of exploration of the mechanism,questions and concerns from overseas scholars,sustainable development and other problems.Future studies should broaden and deepen research insights,including the “overseas free economic zones(OFEZ)” as a general designation to cover all other types of OETCZs,studies on the primary conditions of host countries,exploration of the theoretical issues behind China’s OETCZ,comparative study of OETCZs such as management structures,profit models,environmental standards and legal systems as well as popular issues questioned internationally.
基金supported by the Key Project of the National Natural Science Foundation of China(Grant No.71833004)the National Natural Science Foundation of China(Grant No.71471108)the Fundamental Research Funds for the Central Universities(HUST:2021WKYXQN010).
文摘We propose a simple-to-implement dynamic panel data method to evaluate the impacts of place-based policies.The idea is to exploit both the cross sectional dependence and the serial correlation within a panel and implement a semi difference-in-difference decomposition.Different from the method by Hsiao et al.(2012),the proposed model is easy to implement statistical inferences and can incorporate multiple treated groups at different time thresholds.We use the proposed method to explore the effect of the Free Trade Zone(FTZ)policy implemented in Shanghai at the end of 2013 on local GDP growth rate and compare it with that from Hsiao et al.(2012).The empirical results show that the FTZ does have a positive effect on the local GDP growth rate and it adds 1:21:8 percent point to the growth rate of the GDP per capita for Shanghai in 2014 which is about one fourth to one third of the total GDP growth rate per capita.This effect largely comes from the growth of the tertiary sector.The results lend support to the duplication of FTZ policy to other cities and provinces in China.
基金Project(2005CB623706) supported by the Major State Basic Research Development Program of ChinaProject(50230310) supported by the National Natural Science Foundation of China
文摘The influence of quench transfer time on the microstructure and mechanical properties of 7055 aluminum alloy with and without zirconium was investigated by tensile properties test,optical microscopy,scanning electron microscopy and transmission electron microscopy.For the Zr-free alloy,the strength increases to the highest value at 20 s with transfer time,and then decreases slightly.The elongation decreases slowly with transfer time within 20 s,and more rapidly after 20 s.For the Zr-containing alloy,prolonging transfer time within 20 s results in slight decrease in the strength and elongation,and rapid drop of which is observed after 20 s.For the Zr-free alloy,prolonging transfer time can increase the percentage of intergranular fracture,which is mainly caused by wide grain boundary precipitate free zone.The failure mode of the Zr-containing alloy is modified from the predominant transgranular void growth and intergranular fracture to transgranular shear and intergranular fracture with increase in the transfer time,which is attributed to the wider grain boundary precipitate free zone and coarse equilibrium η phases in the matrix.
基金support from the Natural Sciences and Engineering Research Council of Canada(NSERC)and Rio Tinto,through the NSERC Industry Research Chair in Metallurgy of Aluminum Transformation at University of Quebec at Chicoutimi
文摘Two contents(1.5%and3%)of TiB2nanoparticles were introduced in Al?Mn?Mg3004alloy to study their effects on theelevated-temperature properties.Results show that TiB2nanoparticles were mainly distributed at the interdendritic grain boundarieswith a size range of20?80nm,which is confirmed by transmission electron microscopy(TEM)and X-ray diffraction(XRD).Therefore,the volume fraction of the dispersoid free zones is greatly reduced and the motion of grain boundaries and dislocations isinhibited more effectively at elevated temperature.After peak precipitation heat treatment,the yield strengths in the alloy with3%TiB2addition at room temperature and300°C were increased by20%and13%respectively,while the minimum creep rate at300°Cwas reduced to only1/5of the base alloy free of TiB2,exhibiting a considerable improvement of elevated-temperature properties inAl?Mn?Mg alloys.
文摘The China free trade zone,crucial for advancing a new open economy,has gained significant attention lately.We analyzed 885 papers from Peking University Core and CSSCI journals(2012-2023)using CiteSpace for visualization.Our research results indicate that the literature on China’s free trade zone peaked with 171 articles in 2015,and gradually returned to an average of 45 articles per year.The main research focuses in this field include“institutional innovation”,“negative list”,“financial innovation”,“financial openness”,“opening up to the outside world”,and“economic growth”.In addition,cutting-edge analysis indicates that“dual circulation”and“blockchain”are future research trends.The main authors of the literature include Yang Bin,Zhu Xiaolin,Yuan Bo,Li Meng,Zhao Liang,and others.Their affiliated institutions,research institutes,and universities have not yet formed a clear core circle of authors;The top three research institutions with the highest number of publications are the International Trade and Economic Cooperation Research Institute of the Ministry of Commerce,Kaiyuan Law School of Shanghai Jiao Tong University,and the Comprehensive Research Institute of the Free Trade Zone of Sun Yatsen University.This article delves into the current hot topics and progress in the research of China’s free trade zones,providing important references and inspirations for future scholars in this field.
基金Supported by the Natural National Science Foundation of China(Nos.42076040,41676067)the National Basic Research Program of China(973 Program)(No.2015CB755904)the 111 Project(No.B13030)。
文摘The composition and concentration of dissolved free amino acid(DFAA)of seawater samples collected in May 2016 from the surface to the hadal zone of the northern region of the Yap Trench were analyzed by pre-column derivatization of o-phthalaldehyde.Results show that the average concentration of DFAA in the study area was 0.47±0.36μmol/L.In different sampling stations,the concentrations of DFAA with water depth showed complex variation patterns.At the sediment-seawater interface,the concentrations of DFAA in the western side of the trench were obviously higher than that in its eastern side.In the study area,there were no significant correlations between the concentrations of DFAA and the environmental parameters such as concentrations of chlorophyll a(Chl a),dissolved oxygen(DO),pH,and dissolved inorganic nitrogen(DIN),indicating that the concentrations of DFAA in seawater of the trench are affected by many factors,such as photosynthesis,respiration,temperature,pressure,illumination,and circulation.The dominant DFAA are similar in different water layers of sampling stations,including aspartic acid(Asp),glutamic acid(Glu),glycine(Gly),and serine(Ser).The composition of different amino acids,and the relative abundance of acidic,basic,and neutral amino acids might be related to the sources and consumption of various amino acids.Nine pairs of amino acids in the DFAA showed significantly positive relationship by correlation matrix analysis,suggesting that they might share similar biogeochemical processes.The degradation index(DI)of the DFAA in seawater of the Yap Trench could reflect the degradation,source,and freshness of DFAA in the trench to some extents.This is a preliminary study of amino acids from sea surface to hadal zone in the ocean,more works shall be done in different trenches to reveal their biogeochemical characte ristics in extreme marine environme nts.
文摘Against the backdrop of China's development reality for the time being and upholding the basic logic of boosting the high-quality development of China's economy,the authors give the historical background,realisticclogic,theoretical connotation,and strategic significance of the new development paradigm of dual circulation a thorough interpretation.On this basis,the authors conduct a detailed analysis of the development path between China's Free Trade Zones(FTZs)and the new development paradigm of dual circulation,as well as the new orientation of FTZs under this paradigm.Focusing on systems thinking,the new development paradigm of dual circulation not only opens up a new realm of open economic theory with Chinese characteristics but also enriches the socialist political economy with Chinese characteristics.From the perspective of the new development paradigm of dual circulation,China's FTZs serve as a reform test field and a powerful starting point for driving the high-quality circulation ofChina's economy.From another perspective,it is also an open bridgehead and a significant window for China to participate in international economic circulation.In this sense,China's FTZs remain the key hub linking domestic and international circulations.China's FTZs should be given greater reform autonomy.Whilefocusinggon the differentiated exploration and development models,the dividends of the first trial system should be fully utilized to integrate China's FTZs into the national open development strategy.Thus,high-level open practice can be anticipated to boost the virtuous circle of domestic and foreign economies,with concerted efforts and drive China's economy toward a high-quality future.
基金funded by the National Key R&D Program of China(Grant no.2018YFC1406700)the National Natural Science Foundation of China(Grant no.41776198)the Basic Scientific Fund for National Public Research Institutes of China(Grant no.GY0219Q10)。
文摘One major consequence of global warming in the Antarctic region is increased ice-free zones.Subsequent colonization of these ice-free areas by penguins alters their biogeochemistry,with one prominent example being elevation of inorganic phosphate concentrations around feces depositions.The complex soil biochemistry in the region makes it difficult to define the causal factors of these changes using common research approaches.Here,we addressed the effects of phosphate alone on microbiome structure and dynamics over time by adding external phosphate to selected soils in the Antarctic region.We then analyzed the soil bacterial community composition and diversity using 16S rRNA amplicon sequencing and compared these data with phosphate levels.Parallel geochemical analysis revealed changes in nine soil geochemical factors upon phosphate addition,all of which were relevant to microbiome structure,with soil pH showing the highest correlation.Links between geochemical factors and composition were identified,as were interactions between bacterial taxa.Additionally,Sphingobacteriia,Sphingobacteriales and Chitinophagaceae were found to be more abundant in phosphate-treated soils.Co-occurrence network analysis revealed significantly increased levels of associations in all major network properties over time after phosphate supplementation.Therefore,we conclude phosphate addition has diverse effects on Antarctic soil microbiomes.
