In the wave of urbanization,waterfront landscape optimization is very important,but it is faced with ecological deterioration and other problems.By combing the relevant theories and practices at home and abroad and ma...In the wave of urbanization,waterfront landscape optimization is very important,but it is faced with ecological deterioration and other problems.By combing the relevant theories and practices at home and abroad and making a comparison and summary,the future direction of waterfront research was analyzed.In theory,foreign research has experienced multi-stage development,covering definition classification,design methods,etc.China started late,and is mainly in the exploration stage of learning from foreign experience and combining with local characteristics.The current research and practice have shortcomings such as ignoring users’needs and lacking quantitative evaluation.In the future,the construction of waterfront should focus on the needs of users,use scientific methods to build an evaluation system,integrate multi-disciplines,excavate regional culture,and establish a monitoring mechanism to achieve sustainable and coordinated development of the ecology,society and economy of waterfront.展开更多
Optimizing landscape patterns and management measures would be an effective strategy for the agro-pastoral transitional zone in northern China(ATNC)to adapt to future climate change.Existing studies generally focus on...Optimizing landscape patterns and management measures would be an effective strategy for the agro-pastoral transitional zone in northern China(ATNC)to adapt to future climate change.Existing studies generally focus on cropland or pasture,and thus there is a lack of comprehensive understanding of the landscape composition and configuration in complex agro-pastoral transitional zone.In this study,Ansai County in the ATNC was chosen as an experimental area.Four typical agroecosystem services(AESs),food provision(FP),soil carbon(SC),soil retention(SR)and water yield(WY)from 1980 to 2020,were simulated by spatially integrating a model of the agricultural system using the Environmental Policy Integrated Climate(EPIC)combined with geographic information systems technology.The impacts of different crop types,pasture configurations,and tillage practices on AESs under future climate scenarios were assessed in the context of agro-pastoral transition.Finally,the optimal landscape pattern configuration and management measures were identified through single-objective and multi-objective optimization models.The results showed that under historical scenarios,implementing policies such as converting cropland to pastureland improved SC and SR but reduced FP and WY.Compared to traditional and reduced tillage,no-till practices benefited the enlargement of AESs and the agricultural ecosystem.Notably,future climate change generally negatively affected AESs,especially under the Shared Socioeconomic Pathway(SSP5–8.5)climate scenario.The combination of planting corn and no-till measures would be ideal for optimizing the agricultural ecosystem in Ansai County.For the fragile ATNC,we should advocate conservation agriculture and policies converting cropland to pastureland to mitigate the adverse impacts of climate changes.This study establishes a replicable framework to address landscape management in complex agropastoral systems and offers solutions for climate-resilient land management in global dryland transitional zones,contributing to the realization of regional ecosystem sustainability.展开更多
Supported by the technologies of remote sensing(RS) and geographical informa-tion system(GIS),we chose northwest of Beijing as a study area and gave priority to under-standing of the spatial-temporal characteristics o...Supported by the technologies of remote sensing(RS) and geographical informa-tion system(GIS),we chose northwest of Beijing as a study area and gave priority to under-standing of the spatial-temporal characteristics of landscape pattern change through visually interpreted Landsat TM images of 1989,1996 and 2005.It is believed that there were a series of landscape ecological problems caused by city expansion:landscape ecological connec-tivity was low;landscape structure was simplified;the fragmentation of green land patch was more obvious on the plain areas,moreover,spatial distribution of green land was unbalanced.For this reason,this study adopted accumulative cost distance model,combined with eco-system services and spatial interactions of landscape types,analyzed the spatial difference of the ecological function and the compactness of landscape structure in the study area,and further discussed the landscape pattern optimization proposal.We find that it is essential to protect and establish ecological sources,to establish urban ecological corridors,and to es-tablish ecological nodes at the landscape ecological strategic positions so as to intensify spatial relationships among landscape elements and maintain continuity of landscape eco-logical process and pattern in the course of city expansion.The methods and final results from this study are expected to be useful for landscape ecological planning in Beijing region.展开更多
TOptimization of regional landscape pattern is significant for improving function and value of ecosystem,and restraining the expansion of urban layout.Taking Chengdu City for example,this paper applied RS and GIS tech...TOptimization of regional landscape pattern is significant for improving function and value of ecosystem,and restraining the expansion of urban layout.Taking Chengdu City for example,this paper applied RS and GIS techniques,landscape indexes and ecological service function evaluation to further analyze the temporal and spatial characteristics of landscape pattern and spatial differences of regional ecological functions,and on this basis,identified the spatial distribution of ecological source lands.Based on the long-term objective of building Chengdu into a modem garden city,this paper applied the accumulative cost distance model and introduced garden city theory to construct regional ecological corridors and ecological nodes,and explored the approaches of optimizing landscape pattern of modem garden city.The results showed that a great deal of arable land has been transferred to construction land in the urbanization;intensity of regional ecological functions showed obvious spatial differences;ecological source lands were mainly distributed in the Longmen Mountain,the Qionglai Mountain,the Changqiu Mountain and the Longquan Mountain;according to actual conditions of the study area,the road ecological corridors,river corridors and agricultural corridors in the layout of "four rings and six radial corridors" were constructed;ecological nodes dominated by intersection,wetland and forest park were formed.This research method and results are significant references for building Chengdu into a modem garden展开更多
In view of the seriously-polluted water and broken eco-waterscapes in the Qiusuo Brook on campus of China Three Gorges University,this paper proposed the ecological restoration concept and mode of campus river accordi...In view of the seriously-polluted water and broken eco-waterscapes in the Qiusuo Brook on campus of China Three Gorges University,this paper proposed the ecological restoration concept and mode of campus river according to field investigation and monitoring results,i.e. "reduce exogenous pollution—restore sediment microorganism—build intensified plant filter strip—build river water ecosystem and optimize landscapes—maintain ecological river course".In addition to introducing the design concept and principle of this mode,this paper specified the concrete projects such as sewage interception and water supplement,restoration of sediment microorganism,restoration of water plants,ecological restoration of embankment etc.,and also gave planar layouts and sketches of some projects,in order to provide references for the researches and practices of campus river ecological restoration in China Three Gorges University and other similar projects.展开更多
Optimization is ubiquitous in the control of quantum dynamics in atomic,molecular,and optical systems.The ease or difficulty of finding control solutions,which is practically crucial for developing quantum technologie...Optimization is ubiquitous in the control of quantum dynamics in atomic,molecular,and optical systems.The ease or difficulty of finding control solutions,which is practically crucial for developing quantum technologies,is highly dependent on the geometry of the underlying optimization landscapes.In this review,we give an introduction to the basic concepts in the theory of quantum optimal control landscapes,and their trap-free critical topology under two fundamental assumptions.Furthermore,the effects of various factors on the search effort are discussed,including control constraints,singularities,saddles,noises,and non-topological features of the landscapes.Additionally,we review recent experimental advances in the control of molecular and spin systems.These results provide an overall understanding of the optimization complexity of quantum control dynamics,which may help to develop more efficient optimization algorithms for quantum control systems,and as a promising extension,the training processes in quantum machine learning.展开更多
文摘In the wave of urbanization,waterfront landscape optimization is very important,but it is faced with ecological deterioration and other problems.By combing the relevant theories and practices at home and abroad and making a comparison and summary,the future direction of waterfront research was analyzed.In theory,foreign research has experienced multi-stage development,covering definition classification,design methods,etc.China started late,and is mainly in the exploration stage of learning from foreign experience and combining with local characteristics.The current research and practice have shortcomings such as ignoring users’needs and lacking quantitative evaluation.In the future,the construction of waterfront should focus on the needs of users,use scientific methods to build an evaluation system,integrate multi-disciplines,excavate regional culture,and establish a monitoring mechanism to achieve sustainable and coordinated development of the ecology,society and economy of waterfront.
基金funded by the National Natural Science Foundation of China(Grants No.42471325,42101299 and 42271113)the“Youth Innovation Team Program”of Colleges and Universities in Shandong Province(Grant No.2022KJ248)+1 种基金the Key Project of Teaching Reform of Shandong Normal University(Grant No.2024ZJ37)the Natural Science Foundation of Gansu Province(Grant No.23JRRG0015)。
文摘Optimizing landscape patterns and management measures would be an effective strategy for the agro-pastoral transitional zone in northern China(ATNC)to adapt to future climate change.Existing studies generally focus on cropland or pasture,and thus there is a lack of comprehensive understanding of the landscape composition and configuration in complex agro-pastoral transitional zone.In this study,Ansai County in the ATNC was chosen as an experimental area.Four typical agroecosystem services(AESs),food provision(FP),soil carbon(SC),soil retention(SR)and water yield(WY)from 1980 to 2020,were simulated by spatially integrating a model of the agricultural system using the Environmental Policy Integrated Climate(EPIC)combined with geographic information systems technology.The impacts of different crop types,pasture configurations,and tillage practices on AESs under future climate scenarios were assessed in the context of agro-pastoral transition.Finally,the optimal landscape pattern configuration and management measures were identified through single-objective and multi-objective optimization models.The results showed that under historical scenarios,implementing policies such as converting cropland to pastureland improved SC and SR but reduced FP and WY.Compared to traditional and reduced tillage,no-till practices benefited the enlargement of AESs and the agricultural ecosystem.Notably,future climate change generally negatively affected AESs,especially under the Shared Socioeconomic Pathway(SSP5–8.5)climate scenario.The combination of planting corn and no-till measures would be ideal for optimizing the agricultural ecosystem in Ansai County.For the fragile ATNC,we should advocate conservation agriculture and policies converting cropland to pastureland to mitigate the adverse impacts of climate changes.This study establishes a replicable framework to address landscape management in complex agropastoral systems and offers solutions for climate-resilient land management in global dryland transitional zones,contributing to the realization of regional ecosystem sustainability.
基金Program for New Century Excellent Talent in the University,No.NCET-06-0122The National Water Special Project,No.2008ZX07526-002-02+3 种基金Specific Financial Funds Project of Beijing Academy of Science and Technology (BJAST),Platform Construction for Typical Contaminated Soil Remediation Technology of Bei-jing (2008A-1)Plan Support for Innovative Team (2008A-6) of BJASTNSFC,No.30871964BJNSFC,No.4073036
文摘Supported by the technologies of remote sensing(RS) and geographical informa-tion system(GIS),we chose northwest of Beijing as a study area and gave priority to under-standing of the spatial-temporal characteristics of landscape pattern change through visually interpreted Landsat TM images of 1989,1996 and 2005.It is believed that there were a series of landscape ecological problems caused by city expansion:landscape ecological connec-tivity was low;landscape structure was simplified;the fragmentation of green land patch was more obvious on the plain areas,moreover,spatial distribution of green land was unbalanced.For this reason,this study adopted accumulative cost distance model,combined with eco-system services and spatial interactions of landscape types,analyzed the spatial difference of the ecological function and the compactness of landscape structure in the study area,and further discussed the landscape pattern optimization proposal.We find that it is essential to protect and establish ecological sources,to establish urban ecological corridors,and to es-tablish ecological nodes at the landscape ecological strategic positions so as to intensify spatial relationships among landscape elements and maintain continuity of landscape eco-logical process and pattern in the course of city expansion.The methods and final results from this study are expected to be useful for landscape ecological planning in Beijing region.
基金Sponsored by National"Twelfth Five-year Plan"Science and Technology Support Program(2012BAJ21B08)Program of the Ministry of Environmental Protection
文摘TOptimization of regional landscape pattern is significant for improving function and value of ecosystem,and restraining the expansion of urban layout.Taking Chengdu City for example,this paper applied RS and GIS techniques,landscape indexes and ecological service function evaluation to further analyze the temporal and spatial characteristics of landscape pattern and spatial differences of regional ecological functions,and on this basis,identified the spatial distribution of ecological source lands.Based on the long-term objective of building Chengdu into a modem garden city,this paper applied the accumulative cost distance model and introduced garden city theory to construct regional ecological corridors and ecological nodes,and explored the approaches of optimizing landscape pattern of modem garden city.The results showed that a great deal of arable land has been transferred to construction land in the urbanization;intensity of regional ecological functions showed obvious spatial differences;ecological source lands were mainly distributed in the Longmen Mountain,the Qionglai Mountain,the Changqiu Mountain and the Longquan Mountain;according to actual conditions of the study area,the road ecological corridors,river corridors and agricultural corridors in the layout of "four rings and six radial corridors" were constructed;ecological nodes dominated by intersection,wetland and forest park were formed.This research method and results are significant references for building Chengdu into a modem garden
基金Sponsored by Science Fund of China Three Gorges University(KJ2011B028)National Science Foundation for Young Scientists of China(41401586)
文摘In view of the seriously-polluted water and broken eco-waterscapes in the Qiusuo Brook on campus of China Three Gorges University,this paper proposed the ecological restoration concept and mode of campus river according to field investigation and monitoring results,i.e. "reduce exogenous pollution—restore sediment microorganism—build intensified plant filter strip—build river water ecosystem and optimize landscapes—maintain ecological river course".In addition to introducing the design concept and principle of this mode,this paper specified the concrete projects such as sewage interception and water supplement,restoration of sediment microorganism,restoration of water plants,ecological restoration of embankment etc.,and also gave planar layouts and sketches of some projects,in order to provide references for the researches and practices of campus river ecological restoration in China Three Gorges University and other similar projects.
基金support by the National Key R&D Program of China(No.2018YFA0306703)National Natural Science Foundation of China(NSFC)(Nos.61833010 and 61773232)a grant from the Institute for Guo Qiang,Tsinghua University.H.Rabitz acknowledges the support of US Department of Energy(No.DE-FGO2-O2ER15344).
文摘Optimization is ubiquitous in the control of quantum dynamics in atomic,molecular,and optical systems.The ease or difficulty of finding control solutions,which is practically crucial for developing quantum technologies,is highly dependent on the geometry of the underlying optimization landscapes.In this review,we give an introduction to the basic concepts in the theory of quantum optimal control landscapes,and their trap-free critical topology under two fundamental assumptions.Furthermore,the effects of various factors on the search effort are discussed,including control constraints,singularities,saddles,noises,and non-topological features of the landscapes.Additionally,we review recent experimental advances in the control of molecular and spin systems.These results provide an overall understanding of the optimization complexity of quantum control dynamics,which may help to develop more efficient optimization algorithms for quantum control systems,and as a promising extension,the training processes in quantum machine learning.
