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Unveiling the adaptation strategies of woody plants in remnant forest patches to spatiotemporal urban expansion through leaf trait networks
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作者 Mengping Jian Jingyi Yang 《Forest Ecosystems》 SCIE CSCD 2024年第2期247-254,共8页
Background:With the expansion of urban areas,the remnants of forested areas play a crucial role in preserving biodiversity in urban environments.This study aimed to explore the impact of spatiotemporal urban expansion... Background:With the expansion of urban areas,the remnants of forested areas play a crucial role in preserving biodiversity in urban environments.This study aimed to explore the impact of spatiotemporal urban expansion on the networks of leaf traits in woody plants within remnant forest patches,thereby enhancing our understanding of plant adaptive strategies and contributing to the conservation of urban biodiversity.Methods:Our study examined woody plants within 120 sample plots across 15 remnant forest patches in Guiyang,China.We constructed leaf trait networks (LTNs) based on 26 anatomical,structural,and compositional leaf traits and assessed the effects of the spatiotemporal dynamics of urban expansion on these LTNs.Results and conclusions:Our results indicate that shrubs within these patches have greater average path lengths and diameters than trees.With increasing urban expansion intensity,we observed a rise in the edge density of the LTN-shrubs.Additionally,modularity within the networks of shrubs decreased as road density and urban expansion intensity increased,and increases in the average path length and average clustering coefficient for shrubs were observed with a rise in the composite terrain complexity index.Notably,patches subjected to‘leapfrog’expansion exhibited greater average patch length and diameter than those experiencing edge growth.Stomatal traits were found to have high degree centrality within these networks,signifying their substantial contribution to multiple functions.In urban remnant forests,shrubs bolster their resilience to variable environmental pressures by augmenting the complexity of their leaf trait networks. 展开更多
关键词 Urban remnant forest patch Woody plant Leaf trait network plant adaptation strategy Spatiotemporal urban expansion
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GRU-integrated constrained soft actor-critic learning enabled fully distributed scheduling strategy for residential virtual power plant
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作者 Xiaoyun Deng Yongdong Chen +2 位作者 Dongchuan Fan Youbo Liu Chao Ma 《Global Energy Interconnection》 EI CSCD 2024年第2期117-129,共13页
In this study,a novel residential virtual power plant(RVPP)scheduling method that leverages a gate recurrent unit(GRU)-integrated deep reinforcement learning(DRL)algorithm is proposed.In the proposed scheme,the GRU-in... In this study,a novel residential virtual power plant(RVPP)scheduling method that leverages a gate recurrent unit(GRU)-integrated deep reinforcement learning(DRL)algorithm is proposed.In the proposed scheme,the GRU-integrated DRL algorithm guides the RVPP to participate effectively in both the day-ahead and real-time markets,lowering the electricity purchase costs and consumption risks for end-users.The Lagrangian relaxation technique is introduced to transform the constrained Markov decision process(CMDP)into an unconstrained optimization problem,which guarantees that the constraints are strictly satisfied without determining the penalty coefficients.Furthermore,to enhance the scalability of the constrained soft actor-critic(CSAC)-based RVPP scheduling approach,a fully distributed scheduling architecture was designed to enable plug-and-play in the residential distributed energy resources(RDER).Case studies performed on the constructed RVPP scenario validated the performance of the proposed methodology in enhancing the responsiveness of the RDER to power tariffs,balancing the supply and demand of the power grid,and ensuring customer comfort. 展开更多
关键词 Residential virtual power plant Residential distributed energy resource Constrained soft actor-critic Fully distributed scheduling strategy
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A plant nutrition strategy for ex-situ conservation based on "Ecological Similarity"
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作者 万开元 陈防 +2 位作者 陶勇 陈树森 张过师 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第4期329-334,共6页
This paper reviewed a large scale conservation work of rare and endangered plants currently conducted in main botanical gardens in China, and the existed, predictable and neglected problems on plant growth and reprodu... This paper reviewed a large scale conservation work of rare and endangered plants currently conducted in main botanical gardens in China, and the existed, predictable and neglected problems on plant growth and reproduction in ex-situ conservation process. Considered the status quo in plant ex conservation, a nutritional strategy on the plant conservation was proposed based on 'Ecological Similarity'. Its main idea was that the ex-situ conservation plants coming from natural ecosystem were compulsively allocated in the agro-ecosystems and would return to natural ecosystem ultimately. Therefore, research on plant nutrition of the ex-situ conservation plants should neither just pursue yield and quality as that in agro-ecosystems nor merely stay on intrinsic natures without human intervening. We should give attentions to both of their attributes as in natural ecosystems and in agro-ecosystems, i.e., taking full advantage of plant nutritional measures as in agro-ecosystems to solve actual survival problems of the ex-conservation plants, and ensuring the final goal of returning to nature and playing its ecological role. 展开更多
关键词 ex-situ conservation ecological similarity plant nutrition conservation strategy
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Fluctuating resources,disturbance and plant strategies:diverse mechanisms underlying plant invasions 被引量:2
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作者 Ian J RADFORD 《Journal of Arid Land》 SCIE CSCD 2013年第3期284-297,共14页
This paper examines the hypothesis that non-native plant invasions are related to fluctuating resource availability as proposed by Davis et al. (2000). I measured relative functional responses of both invasive and n... This paper examines the hypothesis that non-native plant invasions are related to fluctuating resource availability as proposed by Davis et al. (2000). I measured relative functional responses of both invasive and native plants to changed resource availability due to nutrient enrichment and rainfall, and to increased disturbance. Data are presented from studies in two contrasting ecosystems. First is a series of glasshouse and field experiments on the invader Hieracium lepidulum and associated invasive and native species in subalpine temperate New Zealand. Second is a field study of invasive and native plant responses to altered disturbance regimes and rainfall from tropical savannas of north eastern Australia. Invaders responded differently from native species to changes in resource availability in both subalpine and tropical studies. However, invaders differed among themselves showing that different species exploit different functional niches to invade their respective habitats. These findings contribute to the contention that the fluctuating resource hypothesis does not provide a universal explanation for plant invasions. The diverse functional responses to increased resource availability among invaders in this and previous studies suggest that the cause of invasion depends on unique combinations of habitat and functional attributes of invaders and native assemblages. Such findings imply that universal predictions of what will happen under climate change scenarios across the globe will be difficult to make. 展开更多
关键词 plant invasion plant strategies C-S-R triangle fluctuating resources DISTURBANCE
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Differences in functional traits and reproductive allocations between native and invasive plants 被引量:6
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作者 WANG Cong-yan ZHOU Jia-wei +2 位作者 LIU Jun XIAO Hong-guang WANG Lei 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第3期516-525,共10页
Because co-occurring native and invasive plants are subjected to similar environmental selection pressures,the differences in functional traits and reproductive allocation strategies between native and invasive plants... Because co-occurring native and invasive plants are subjected to similar environmental selection pressures,the differences in functional traits and reproductive allocation strategies between native and invasive plants may be closely related to the success of the latter.Accordingly,this study examines differences in functional traits and reproductive allocation strategies between native and invasive plants in Eastern China.Plant height,branch number,reproductive branch number,the belowground-to-aboveground biomass ratio,and the reproductive allocation coefficient of invasive plants were all notably higher than those of native species.Additionally,the specific leaf area(SLA)values of invasive plants were remarkably lower than those of native species.Plasticity indexes of SLA,maximum branch angle,and branch number of invasive plants were each notably lower than those of native species.The reproductive allocation coefficient was positively correlated with reproductive branch number and the belowground-to-aboveground biomass ratio but exhibited negative correlations with SLA and aboveground biomass.Plant height,branch number,reproductive branch number,the belowground-to-aboveground biomass ratio,and the reproductive allocation coefficient of invasive plants may strongly influence the success of their invasions. 展开更多
关键词 functional trait specific leaf area reproductive allocation strategy phenotypic plasticity invasive plant
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Genomic dissection of widely planted soybean cultivars leads to a new breeding strategy of crops in the post-genomic era 被引量:4
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作者 Xinpeng Qi Bingjun Jiang +8 位作者 Tingting Wu Shi Sun Caijie Wang Wenwen Song Cunxiang Wu Wensheng Hou Qijian Song Hon-Ming Lam Tianfu Han 《The Crop Journal》 SCIE CSCD 2021年第5期1079-1087,共9页
Soybeans specially the widely planted cultivars have been dramatically improved in agronomic performance and is well adapted to local planting environments after long-time domestication and breeding.Uncovering the uni... Soybeans specially the widely planted cultivars have been dramatically improved in agronomic performance and is well adapted to local planting environments after long-time domestication and breeding.Uncovering the unique genomic features of popular cultivars will help to understand how soybean genomes have been modified through breeding.We re-sequenced 134 soybean cultivars that were released and most widely planted over the last century in China.Phylogenetic analyses established that these cultivars comprise two geographically distinct sub-populations:Northeast China (NE) versus the HuangHuai-Hai River Valley and South China (HS).A total of 309 selective regions were identified as being impacted by geographical origins.The HS sub-population exhibited higher genetic diversity and linkage disequilibrium decayed more rapidly compared to the NE sub-population.To study the association between phenotypic differences and geographical origins,we recorded the vegetative period under different growing conditions for two years,and found that clustering based on the phenotypic data was closely correlated with cultivar geographical origin.By iteratively calculating accumulated genetic diversity,we established a platform panel of cultivars and have proposed a novel breeding strategy named "Potalaization"for selecting and utilizing the platform cultivars that represent the most genetically diversity and the highest available agronomic performance as the "plateau"for accumulating elite loci and traits,breeding novel widely adapted cultivars,and upgrading breeding technology.In addition to providing new genomic information for the soybean research community,the "Potalaization"strategy that we devised will also be practical for integrating the conventional and molecular breeding programs of crops in the post-genomic era. 展开更多
关键词 Soybean Widely planted cultivars Genomic re-sequencing Breeding strategy
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Ethnobotanical Study towards Conservation of Medicinal and Aromatic Plants in Upper Catchments of Dhauli Ganga in the Central Himalaya 被引量:3
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作者 L.S.KANDARI P.C.PHONDANI +2 位作者 K.C.PAYAL K.S.RAO R.K.MAIKHURI 《Journal of Mountain Science》 SCIE CSCD 2012年第2期286-296,共11页
The present study broadly focused on medicinal plant species collected from wild by the villagers for different purposes in the upper catchment of Dhauli Ganga in Nanda Devi Biosphere Reserve(NDBR),in the central Hima... The present study broadly focused on medicinal plant species collected from wild by the villagers for different purposes in the upper catchment of Dhauli Ganga in Nanda Devi Biosphere Reserve(NDBR),in the central Himalaya.A schedule based survey was conducted during the years 2003-2005 in 15 villages of Chamoli district part of the NDBR.Information was collected from collectors, vaidya(medicine man)and those dealing with domestication and marketing of the medicinal plants. The aim of the study was to understand the prioritiesed medicinal plants,their mode of collection and document their ethnobotanical uses by the Bhotiya tribal communities,in this world heritage site. During the survey,50 medicinal plants belonging to 31 families and 44 genera were documented.Out of these,70% were harvested from the wild,22% were cultivated and 8% were cultivated as well as wild harvested.Of the cultivated species,8% were found growing in the kitchen gardens and 14%in the agricultural fields.However,42%of the plants had their roots and rhizomes used followed by leaves (26%),seeds(10%),seed and leaf(8%),bark and whole plant(6%)and flower(1%).Most plants were reported to be used for rheumatism(16),followed by stomach disorder(14),cold and cough(11),and jaundice(9).Thirty three plants species were reported to have more than one therapeutic uses,while 17 species were reported to be used against single ailment.The distance of villages from road head was one of the factors contributing to the decline in the medicinal plant population in their natural habitats. The availability of medicinal plants increased with increase in distance from road head and also the peoples'dependence on them.Documentation of the traditional knowledge will help in conservation of knowledge and also opportunity for using it for future training and use.The result of this study will help in promoting sustainable cultivation and implementation in conservation protocol of those species,which are in the verge of extinction in this region. 展开更多
关键词 Conservation strategy ETHNOBOTANY Medicinal plants Traditional communities Central Himalaya
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Optimum control strategy for all-variable speed chiller plant 被引量:3
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作者 蒋小强 龙惟定 李敏 《Journal of Central South University》 SCIE EI CAS 2011年第2期573-579,共7页
The optimum control strategy and the saving potential of all variable chiller plant under the conditions of changing building cooling load and cooling water supply temperature were investigated. Based on a simulation ... The optimum control strategy and the saving potential of all variable chiller plant under the conditions of changing building cooling load and cooling water supply temperature were investigated. Based on a simulation model of water source chiller plant established in dynamic transient simulation program (TRNSYS),the four-variable quadratic orthogonal regression experiments were carried out by taking cooling load,cooling water supply temperature,cooling water flow rate and chilled water flow rate as variables,and the fitting formulas expressing the relationships between the total energy consumption of chiller plant with the four selected parameters was obtained. With the SAS statistical software and MATHEMATICA mathematical software,the optimal chilled water flow rate and cooling water flow rate which result in the minimum total energy consumption were determined under continuously varying cooling load and cooling water supply temperature. With regard to a chiller plant serving an office building in Shanghai,the total energy consumptions under different control strategies were computed in terms of the forecasting function of cooling load and water source temperature. The results show that applying the optimal control strategy to the chiller plant can bring a saving of 23.27% in power compared with the corresponding conventional variable speed plant,indicating that the optimal control strategy can improve the energy efficiency of chiller plant. 展开更多
关键词 chiller plant control strategy variable speed cooling water flow rate chilled water flow rate
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Folk nomenclature of plants in Cistanche deserticola-associated community in South Gobi, Mongolia 被引量:2
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作者 Urtnasan Mandakh Munkhjargal Battseren +4 位作者 Danzanchadav Ganbat Turuutuvshin Ayanga Zolzaya Adiya Almaz Borjigidai Chunlin Long 《Plant Diversity》 SCIE CAS CSCD 2020年第6期434-442,共9页
Cistanche deserticola is an important medicinal plant in Mongolia.Despite its significant role in local healing systems,little traditional knowledge had been reported.The present study investigated folk names of C.des... Cistanche deserticola is an important medicinal plant in Mongolia.Despite its significant role in local healing systems,little traditional knowledge had been reported.The present study investigated folk names of C.deserticola and other species of the same community in Umnugobi Province,South Gobi region of Mongolia,based on ethnobotanical approaches.The high correspondence between folk names and scientific names of plant species occurring in Cistanche-associated community shows the scientific meaning of folk nomenclature and classification in Mongolia.The Mongolian and folk names of plants were formed on the basis of observations and understanding of wild plants including their morphology,phenology and traditional uses as well.Results from this study will support the conservation of C.deserticola itself,a rare and endangered plant species listed in the Monglian Red Data Book.Our documentation of folk nomenclature based on 96 plant species in the Cistanche community,as a part of traditional knowledge associated with biodiversity,will be very helpful for making strategy of plant biodiversity conservation in Mongolia. 展开更多
关键词 Cistanche deserticola plant community ETHNOBOTANY Folk nomenclature Conservation strategy South gobi of Mongolia
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Trait-based representation of hydrological functional properties of plants in weather and ecosystem models 被引量:2
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作者 Ashley M. Matheny Golnazalsadat Mirfenderesgi Gil Bohrer 《Plant Diversity》 SCIE CAS CSCD 北大核心 2017年第1期1-12,共12页
Land surface models and dynamic global vegetation models typically represent vegetation through coarse plant functional type groupings based on leaf form, phenology, and bioclimatic limits. Although these groupings we... Land surface models and dynamic global vegetation models typically represent vegetation through coarse plant functional type groupings based on leaf form, phenology, and bioclimatic limits. Although these groupings were both feasible and functional for early model generations, in light of the pace at which our knowledge of functional ecology, ecosystem demographics, and vegetation-climate feedbacks has advanced and the ever growing demand for enhanced model performance, these groupings have become antiquated and are identified as a key source of model uncertainty. The newest wave of model development is centered on shifting the vegetation paradigm away from plant functional types(PFTs)and towards flexible trait-based representations. These models seek to improve errors in ecosystem fluxes that result from information loss due to over-aggregation of dissimilar species into the same functional class. We advocate the importance of the inclusion of plant hydraulic trait representation within the new paradigm through a framework of the whole-plant hydraulic strategy. Plant hydraulic strategy is known to play a critical role in the regulation of stomatal conductance and thus transpiration and latent heat flux. It is typical that coexisting plants employ opposing hydraulic strategies, and therefore have disparate patterns of water acquisition and use. Hydraulic traits are deterministic of drought resilience, response to disturbance, and other demographic processes. The addition of plant hydraulic properties in models may not only improve the simulation of carbon and water fluxes but also vegetation population distributions. 展开更多
关键词 Hydraulic traits Land-surface modeling Whole-plant hydraulic strategy Trait-based models Demographic models plant functional type
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Increased dependence on nitrogen-fixation of a native legume in competition with an invasive plant 被引量:1
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作者 Meixu Han Haiyang Zhang +12 位作者 Mingchao Liu Jinqi Tang Xiaocheng Guo Weizheng Ren Yong Zhao Qingpei Yang Binglin Guo Qinwen Han Yulong Feng Zhipei Feng Honghui Wu Xitian Yang Deliang Kong 《Plant Diversity》 SCIE CAS CSCD 2024年第4期510-518,共9页
Suppression of roots and/or their symbiotic microorganisms,such as mycorrhizal fungi and rhizobia,is an effective way for alien plants to outcompete native plants.However,little is known about how invasive and native ... Suppression of roots and/or their symbiotic microorganisms,such as mycorrhizal fungi and rhizobia,is an effective way for alien plants to outcompete native plants.However,little is known about how invasive and native plants interact with the quantity and activity of nutrient-acquisition agents.Here a pot experiment was conducted with monoculture and mixed plantings of an invasive plant,Xanthium strumarium,and a common native legume,Glycine max.We measured traits related to root and nodule quantity and activity and mycorrhizal colonization.Compared to the monoculture,fine root quantity(biomass,surface area)and activity(root nitrogen(N)concentration,acid phosphatase activity)of G.max decreased in mixed plantings;nodule quantity(biomass)decreased by 45%,while nodule activity in Nfixing via rhizobium increased by 106%;mycorrhizal colonization was unaffected.Contribution of N fixation to leaf N content in G.max increased in the mixed plantings,and this increase was attributed to a decrease in the rhizosphere soil N of G.max in the mixed plantings.Increased root quantity and activity,along with a higher mycorrhizal association was observed in X.strumarium in the mixed compared to monoculture.Together,the invasive plant did not directly scavenge N from nodule-fixed N,but rather depleted the rhizosphere soil N of the legume,thereby stimulating the activity of N-fixation and increasing the dependence of the native legume on this N source.The quantity-activity framework holds promise for future studies on how native legumes respond to alien plant invasions. 展开更多
关键词 Mycorrhizal strategy Nitrogen depletion plant invasion Root nutrient acquisition strategy Symbiotic nitrogen fixation
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Reliability-Centered Maintenance-Based Maintenance Decision in New Nuclear Power Plants
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作者 黄立军 陈宇 +1 位作者 马沂荩 吴进 《Journal of Donghua University(English Edition)》 EI CAS 2016年第2期248-251,共4页
Taking the project of introducing reliability-centered maintenance( RCM) into maintenance decision in an AP1000 nuclear power plant( NPP) under construction as the research object,an improved RCM methodology was propo... Taking the project of introducing reliability-centered maintenance( RCM) into maintenance decision in an AP1000 nuclear power plant( NPP) under construction as the research object,an improved RCM methodology was proposed, and the application software and an RCM-based maintenance strategies management system were designed. In the pilot project,the RCMbased maintenance decision methodology had been applied to determining the maintenance strategies for two systems. Both the decision process and the results were described in this paper. The achievements of this project promoted the introduction and routinization of an advanced and effective maintenance decision mode in nuclear power field,which could provide valuable reference for new NPPs in China. 展开更多
关键词 reliability-centered maintenance(RCM) maintenance strategy maintenance decision maintenance program nuclear power plant(NPP)
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Plant Factory Engineering Strategy of Japanese Manufacturer and Agri-Business Innovation
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作者 Suguru Yanata Takao Nomakuchi Kaori Ishibashi 《Journal of Agricultural Chemistry and Environment》 2015年第2期15-19,共5页
These days, some manufacturing enterprises which are forced to diversify management enter Agri- Business and plant factory business, make an Innovation utilizing high research and development ability and enough capita... These days, some manufacturing enterprises which are forced to diversify management enter Agri- Business and plant factory business, make an Innovation utilizing high research and development ability and enough capital. As Agri-Business Innovation in Japan, this study examinedNK Agri, a subsidiary company of Noritsu Koki, which is a motion picture producer and machinery maker, based on Industrial Cluster Theory and Diamond Model by Michael E. Porter. The important points to enter Agri-Business of manufacturing enterprises were summed up as below. 1) New coming manufacture enterprises can form Industrial Cluster with farmhouse and foods makers, and enhance productivity and competitiveness. 2) New coming manufacture enterprises can enhance productive efficiency by collaborating with orthodox farmhouses as important partners. 3) Re- search institutions such as universities and local government should support for forming and development of Agri Industrial Cluster by manufacture enterprises. Agri Industrial Cluster by manufacture enterprises can improve local economy, so local government should prepare for the system to expand support as a policy. 展开更多
关键词 plant FACTORY ENGINEERING strategy of JAPANESE MANUFACTURER and Agri-Business INNOVATION
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Analysis of Application Status and Recommendations for Shade-Tolerant Lawns and Ground Cover Plants in the West Lake Scenic Area
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作者 Zhishan YE Yujie CHEN +2 位作者 Yi ZHANG Jingqian TANG Jin MA 《Asian Agricultural Research》 2023年第7期28-29,38,共3页
Taking 8 parks in Xihu Scenic Area as the survey objects, this study found that there are 77 kinds of shade-tolerant lawns and ground cover plants under the forest in good growth condition, and there are 3 types of ap... Taking 8 parks in Xihu Scenic Area as the survey objects, this study found that there are 77 kinds of shade-tolerant lawns and ground cover plants under the forest in good growth condition, and there are 3 types of application forms: dense forest, sparse forest and forest edge. In response to the existing problems, it is proposed that it is necessary to adhere to principles of ecology, adapt to local conditions and plant suitable varieties in accordance with local conditions, develop and use new varieties of wild shade-tolerant lawns and ground cover plants, and strengthen the promotion of the mixed planting model of shade-tolerant lawns and ground cover plants, so as to provide guidance for the better use of shade-tolerant lawns and ground cover under the forest in the West Lake Scenic Area in the future. 展开更多
关键词 West Lake Scenic Area Shade-tolerant lawn and ground cover plants Application STRATEGIES
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Y沸石中Cu(Ⅰ)的可控构筑及其乙烯/乙烷吸附分离性能研究 被引量:1
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作者 张凯博 沈佳新 +3 位作者 李玉霞 谈朋 刘晓勤 孙林兵 《化工学报》 EI CSCD 北大核心 2024年第4期1607-1615,共9页
乙烯(C_(2)H_(4))和乙烷(C_(2)H_(6))物理性质相似,其高效分离具有挑战性。利用Cu(Ⅰ)活性位与C_(2)H_(4)间的π络合作用,Cu(Ⅰ)基吸附剂能在温和条件下选择性地分离C_(2)H_(4)和C_(2)H_(6),显著降低传统低温精馏分离过程的能耗。Cu(Ⅰ)... 乙烯(C_(2)H_(4))和乙烷(C_(2)H_(6))物理性质相似,其高效分离具有挑战性。利用Cu(Ⅰ)活性位与C_(2)H_(4)间的π络合作用,Cu(Ⅰ)基吸附剂能在温和条件下选择性地分离C_(2)H_(4)和C_(2)H_(6),显著降低传统低温精馏分离过程的能耗。Cu(Ⅰ)由Cu(Ⅱ)还原制得,但Cu(Ⅱ)还原的不可控、能耗高且Cu(Ⅰ)收率低一直是Cu(Ⅰ)基吸附剂应用的障碍。采用选择性还原策略(SRS)成功在Y型沸石中选择性地构筑了Cu(Ⅰ)活性位,实现了温和条件下C_(2)H_(4)/C_(2)H_(6)的吸附分离。利用甲醛(HCHO)蒸气扩散传递,与沸石中的Cu(Ⅱ)反应,实现了低温(140℃)下Cu(Ⅰ)的选择性构筑;制得的Cu(Ⅰ)Y具有优异的C_(2)H_(4)/C_(2)H_(6)吸附分离性能,Cu(Ⅰ)Y的选择性达16.3,远高于Cu(Ⅱ)Y的3.2。机理研究表明,HCHO与Y沸石中的Cu(Ⅱ)发生氧化还原反应,在得到Cu(Ⅰ)的同时生成CO_(2)和H_(2)O。 展开更多
关键词 吸附 乙烯/乙烷分离 选择性 一价铜 选择性还原策略 沸石
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Stand biomass of Pinus sylvestris var. mongolica plantations benefits from high density monocultures in the boreal zone
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作者 Bingming Chen Shensi Liu +8 位作者 Jinghua Yu Yanqing Huang Shuai Yu Huanchu Liu Tianyu Zhang Xiangdong Liu Guangze Jin Wei Chen Xingyuan He 《Forest Ecosystems》 SCIE CSCD 2024年第5期650-658,共9页
Pinus sylvestris var.mongolica(P.sylvestris)plantations are extensively established in the boreal zone.Increasing stand biomass of these plantations can effectively enhance carbon stock,which is crucial for mitigating... Pinus sylvestris var.mongolica(P.sylvestris)plantations are extensively established in the boreal zone.Increasing stand biomass of these plantations can effectively enhance carbon stock,which is crucial for mitigating climate change.However,the current understanding of optimizing plantation strategies to maximize stand biomass is primarily derived from experiments in tropical and subtropical zones,which is difficult to extend to the boreal due to substantial climatic differences.Based on a comprehensive dataset from 1,076 sample plots of P.sylvestris plantations in the boreal zone of China,we evaluated the effects of tree species richness and stand density on tree height,diameter at breast height(DBH),and stand biomass to investigate the optimal plantation strategy.Furthermore,we examined how these effects changed with stand age and investigated their relative importance.We found that monocultures at a high stand density of 2,000–2,500ha^(−1) were the optimal plantation strategy to maximize stand biomass(107.5Mg·ha^(−1)),and this held true at almost all stand ages.Unfortunately,this strategy resulted in low species richness and small individual trees(10.6m height and 9.8cm DBH),thus presenting a trade-off.In addition,as stand age increased,the effect of tree species richness on stand biomass shifted from positive to negative,but the effect of stand density was always positive.Overall,stand age had the greatest effect on stand biomass,followed by stand density and then tree species richness.Our findings reveal a distinct plantation strategy for optimizing stand biomass of P.sylvestris plantations in the boreal zone.More importantly,this study highlights that(1)maximizing stand biomass in the boreal zone may compromise tree species richness;(2)net effects of tree species richness on stand biomass are not always positive,as negative selection effects offset positive complementary effects. 展开更多
关键词 Boreal forests Cold region Forestry application Mongolian Scots pine planting strategy Tree diversity
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A Study on the Translation of Plant Images in Qu Yuan’s Li Sao
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作者 ZHANG Fang-fang CAI Ke-ying +1 位作者 YANG Lei BAO De-wang 《Journal of Literature and Art Studies》 2024年第5期325-329,共5页
The renowned masterpiece“Li Sao”by Qu Yuan contains numerous plant images for“expressing emotions and aspirations.”Exploring methods of translating plant imagery has greatly assisted in disseminating Chinese class... The renowned masterpiece“Li Sao”by Qu Yuan contains numerous plant images for“expressing emotions and aspirations.”Exploring methods of translating plant imagery has greatly assisted in disseminating Chinese classical culture and facilitating cross-cultural communication.This study conducts a comparative analysis of three translations of“Li Sao”by Xu Yuanchong,Yang Xianyi,and Hawkes,aiming to understand the different approaches to translating plant imagery and explore variations in translation effectiveness.Through data collection,comparative analysis,and case studies,this research reveals that Xu Yuanchong emphasizes free translation,Yang Xianyi tends towards literal translation,and Hawkes adopts a combination of literal,free,and phonetic translation methods. 展开更多
关键词 Li Sao plant imagery translation strategies
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Biological protection of plants in agricultular landscape—state of the art, problems and ways of their decision
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作者 Sokolov M S Kolombet L V 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2004年第4期398-400,共3页
Biological protection of plants: definition and objectives. Technologically, biological protection of plants (hereinafter bioprotection) is a high agricultural technology involving agricultural landscape approach and ... Biological protection of plants: definition and objectives. Technologically, biological protection of plants (hereinafter bioprotection) is a high agricultural technology involving agricultural landscape approach and basee on an ecological imperative, namely “use living beings against living beings”. In a wide sense, present-day bioprotection is a fundamental and applied field of knowledge providing harmless suppression of harmful agents during cultivation and storage of agricultural crops by use natural and (or) artificially constructed organisms (including genetically modified ones having pesticidal properties) and products of their live cycle. The overall objective of bioprotection consists in producing harmless, profitable and high-quality vegetative raw material, food, fodder. At the same time, bioprotection agrotechnologies are important environment forming and environment maintaining factors, steady and positively influencing the health of both rural ethnos, and agrosphere as a whole. Realization of integrated bioprotection approaches should provide minimum destruction of beneficial and non-target organisms, excluding the succession of harmful species and appearance of species resistant to biocontrol agents. 2. Theoretical foundation of bioprotection. The following postulates and imperatives of biosphere science, agrarian and social ecology make the scientific basis of bioprotection: “The Nature knows the how and why of things better”; Steady, balanced development of agrosphere (proceeding from a presumption of life support) is based on biocentrism and biosystem relations, or consortism of its consorbents; Control of the agrosphere by human beings could be effective only in case of primary realization of biocenotic regulation; Biocenotic regulation, dynamics of the number and species diversity of agrosphere is realized through trophically similar cenoconsorcia and tritrophic systems, that provides maintenance and preservation of trophically proved critical level of harmful species; Biotic and man-caused effects on argosphere are regularly registered and the degree of these effects on non-target biota is comprehensively estimated, operative measures to prevent its elimination are taken, if necessary. Thus, artificial agrocenoses and agroecosystems are immanent components of the agrospehere. Functioning of their bioresources meets the same laws of the Nature, as the functioning of the biota of natural ground ecosystems. When agrocenoses and agroecosystems make a single whole with the elements of preserved natural ecosystems, reproduction of bioresources, their protection against expansion of competitive and cosmopolitan species are realized at a level of steadily functioning agrocenoconsorcia, where “living beings protect living beings”. 3. Bioprotection and agrosphere. Present-day bioprotection is based on agrolandscape approaches. The major global function of the agrolandscape involves utilization of maximum quantity of solar energy. Modern geosystemic definition of the agrolandscape emphasizes not only its production abilities, but also its social and design-aesthetic functions: “... is an existing geosystem anthropogenically modified for agricultural use and formed with the purpose of the most effective and ecologically safe use of natural and anthropogenic resources for manufacturing economically and socially reasonable quantity of agricultural production and creation of the welfare and spiritual environment for harmonious development of humans” (A.V. Zaharenko, 2004) . The paradox is, that current plant growing (initially based on the use of gratuitous, inexhaustible solar energy and renewed resources of agrosphere) has turned in the most resource uneconomic branch of economy by the beginning of XXI century. Therefore agricultural technologies, including protection of plants, should mostly use renewable, instead of exhaustible resources and not renewable sources of raw material and energy, materialized in agrochemicals, chemical pesticides, oil 展开更多
关键词 植物 生物保护 农业景观 农业气候 设施园艺
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高等植物光系统Ⅰ的研究(Ⅰ)──叶绿体中存在两种光系统Ⅰ 被引量:12
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作者 高荣孚 郑彩霞 +1 位作者 童年 何平 《北京林业大学学报》 CAS CSCD 北大核心 1997年第1期13-20,共8页
用含有PEG的提取介质有效地提取和分离了油松、毛白杨、豌豆及菠菜的类囊体膜片,经改进了的增溶方法增溶光合色素蛋白复合物,有效地、完整地将PSI从膜结构上溶解下来.溶解液经DOCPAGE分离,均可得到迁移率相近的具光... 用含有PEG的提取介质有效地提取和分离了油松、毛白杨、豌豆及菠菜的类囊体膜片,经改进了的增溶方法增溶光合色素蛋白复合物,有效地、完整地将PSI从膜结构上溶解下来.溶解液经DOCPAGE分离,均可得到迁移率相近的具光系统Ⅰ活性的两条稳定的绿带,经超速离心及不同浓度毛地黄皂苷和Tween20处理,证明它们是两种PSI,称为PSI1和PSI2.SDSPAGE分析证明这两种复合物多肽种类相同,部分多肽的组成在比例上存在差异,证明在高等植物中存在两种PSI。 展开更多
关键词 高等植物 光系统 异质性 叶绿体
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Cs(Ⅰ)在桃花江水底沉积物上的吸附模型 被引量:1
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作者 靳强 杨俊威 +4 位作者 高超 张震 陈宗元 郭治军 吴王锁 《原子能科学技术》 EI CAS CSCD 北大核心 2019年第10期1788-1796,共9页
通过批式吸附实验研究了接触时间、固液比、溶液pH值、离子强度、温度、Cs(Ⅰ)浓度和沉积物组分等对Cs(Ⅰ)在桃花江水底沉积物上吸附作用的影响。结果表明,样品中黏土组分含量和溶液离子强度对Cs(Ⅰ)吸附影响显著,而溶液pH值和温度对Cs(... 通过批式吸附实验研究了接触时间、固液比、溶液pH值、离子强度、温度、Cs(Ⅰ)浓度和沉积物组分等对Cs(Ⅰ)在桃花江水底沉积物上吸附作用的影响。结果表明,样品中黏土组分含量和溶液离子强度对Cs(Ⅰ)吸附影响显著,而溶液pH值和温度对Cs(Ⅰ)吸附几乎无影响,说明Cs(Ⅰ)的吸附机理为黏土上的阳离子交换作用;Cs(Ⅰ)在桃花江水底沉积物上的解吸具有滞后性,解吸速率明显小于吸附速率。利用磨损边缘-基面位点概念模型的框架,构建了Cs(Ⅰ)在桃花江水底沉积物上的吸附模型。研究所得结果有助于精确预测Cs(Ⅰ)在桃花江水底沉积物上的吸附作用,为桃花江核电厂的周围水体质量评价、废水排放标准建立和核事故应急处理提供了基础数据和参考模型。 展开更多
关键词 Cs() 桃花江核电厂 桃花江水底沉积物 吸附 建模
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