Understanding how ecological engineering influences the trade-offs and synergies among regional ecosystem services can provide valuable insights for enhancing ecosystem functionality and promoting a virtuous and susta...Understanding how ecological engineering influences the trade-offs and synergies among regional ecosystem services can provide valuable insights for enhancing ecosystem functionality and promoting a virtuous and sustainable ecological cycle.This study focuses on the Changbai Mountain region,a key ecological conservation area in northeastern China.It employs global spatial autocorrelation analysis and bivariate spatial correlation methods to explore the spatial patterns of five key ecosystem services—soil retention,carbon sequestration,water purification,habitat quality,and water yield—as well as the spatial heterogeneity of the trade-offs and synergies among them.The results indicate that:(1)Forest land is the dominant land-use type in the study area,with land-use changes primarily occurring among grassland,forest,and cropland.(2)The implementation of the“Mountain-River Project”has significantly enhanced ecosystem service capacities.Specifically,the average habitat quality has remained stable at 0.97;average water yield increased from 716 mm to 743 mm;average nitrogen purification rose from 0.025 to 0.028;and total soil retention increased from 8.7×10^(7)tons to 5.09×10^(8)tons.(3)Synergistic relationships dominate the interactions among individual ecosystem services in the Changbai Mountain region.The implementation of ecological engineering has further strengthened synergies—particularly among soil retention,water yield,and other services.However,the short-term impacts of the project have somewhat weakened the synergies between water purification and other ecosystem services.These findings offer a novel perspective for understanding the effects of ecological engineering on ecosystem services and provide a scientific basis for future ecological restoration planning and management.展开更多
Hydrogen,clean,efficient and zero-carbon,is seen as a most promising energy source.The use of existing gas pipelines for hydrogenenatural gas transportation is considered to be an effective way to achieve long-distanc...Hydrogen,clean,efficient and zero-carbon,is seen as a most promising energy source.The use of existing gas pipelines for hydrogenenatural gas transportation is considered to be an effective way to achieve long-distance,large-scale,efficient,and economical hydrogen transportation.However,the pipelines for hydrogenenatural gas transportation contain lots of impurities(e.g.,CH_(4),high-pressure H_(2),H_(2)S and CO_(2))and free water,which will inevitably lead to corrosion and hydrogen embrittlement.This paper presents a systematic review of research and an outlook for corrosion and hydrogen embrittlement in hydrogenenatural gas pipeline transportation.The results show that gas-phase hydrogen charging is suitable for hydrogenenatural gas transportation,but this technique lacks technical standards.By contrast,the liquid-phase hydrogen charging technique is more mature but has large deviation from the engineering reality.In the hydrogenenatural gas transportation pipelines,corrosion and hydrogen embrittlement are synergetic and competitive,but the failure mechanism and change law when corrosion and hydrogen embrittlement coexist remain unclear,which need to be further clarified by experiments.The failure mechanism is believed to be mainly sensitive to three key factors,i.e.,the H_(2)S/CO_(2)partial pressure ratio,the hydrogen blending ratio,and material strength.The increase of the three factors will make the pipeline materials more corrosive and more sensitive to hydrogen embrittlement.The researchfindings can be used as a reference for research and development of long-distance hydrogenenatural gas transportation technology and will drive the high-quality development of the hydrogenenatural gas blending industry.展开更多
基金supported by the coupling mechanism and system restoration modes of Mountains-Rivers-Forests-Farmlands-Lakes-Grasslands,National Key Research and Development Program of the 14th Five-Year,China(2022YFF1303201).
文摘Understanding how ecological engineering influences the trade-offs and synergies among regional ecosystem services can provide valuable insights for enhancing ecosystem functionality and promoting a virtuous and sustainable ecological cycle.This study focuses on the Changbai Mountain region,a key ecological conservation area in northeastern China.It employs global spatial autocorrelation analysis and bivariate spatial correlation methods to explore the spatial patterns of five key ecosystem services—soil retention,carbon sequestration,water purification,habitat quality,and water yield—as well as the spatial heterogeneity of the trade-offs and synergies among them.The results indicate that:(1)Forest land is the dominant land-use type in the study area,with land-use changes primarily occurring among grassland,forest,and cropland.(2)The implementation of the“Mountain-River Project”has significantly enhanced ecosystem service capacities.Specifically,the average habitat quality has remained stable at 0.97;average water yield increased from 716 mm to 743 mm;average nitrogen purification rose from 0.025 to 0.028;and total soil retention increased from 8.7×10^(7)tons to 5.09×10^(8)tons.(3)Synergistic relationships dominate the interactions among individual ecosystem services in the Changbai Mountain region.The implementation of ecological engineering has further strengthened synergies—particularly among soil retention,water yield,and other services.However,the short-term impacts of the project have somewhat weakened the synergies between water purification and other ecosystem services.These findings offer a novel perspective for understanding the effects of ecological engineering on ecosystem services and provide a scientific basis for future ecological restoration planning and management.
基金supported by the key special fund of the National Key Research and Development Program"Hydrogen Energy Technology"for"Research on the mechanism and compatibility of hydrogen permeation and diffusion in me-dium-and low-pressure pure hydrogen and hydrogen-doped gas pipeline systems"(No.2021YFB4001601).
文摘Hydrogen,clean,efficient and zero-carbon,is seen as a most promising energy source.The use of existing gas pipelines for hydrogenenatural gas transportation is considered to be an effective way to achieve long-distance,large-scale,efficient,and economical hydrogen transportation.However,the pipelines for hydrogenenatural gas transportation contain lots of impurities(e.g.,CH_(4),high-pressure H_(2),H_(2)S and CO_(2))and free water,which will inevitably lead to corrosion and hydrogen embrittlement.This paper presents a systematic review of research and an outlook for corrosion and hydrogen embrittlement in hydrogenenatural gas pipeline transportation.The results show that gas-phase hydrogen charging is suitable for hydrogenenatural gas transportation,but this technique lacks technical standards.By contrast,the liquid-phase hydrogen charging technique is more mature but has large deviation from the engineering reality.In the hydrogenenatural gas transportation pipelines,corrosion and hydrogen embrittlement are synergetic and competitive,but the failure mechanism and change law when corrosion and hydrogen embrittlement coexist remain unclear,which need to be further clarified by experiments.The failure mechanism is believed to be mainly sensitive to three key factors,i.e.,the H_(2)S/CO_(2)partial pressure ratio,the hydrogen blending ratio,and material strength.The increase of the three factors will make the pipeline materials more corrosive and more sensitive to hydrogen embrittlement.The researchfindings can be used as a reference for research and development of long-distance hydrogenenatural gas transportation technology and will drive the high-quality development of the hydrogenenatural gas blending industry.
