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Shrub modulates the stoichiometry of moss and soil in desert ecosystems, China 被引量:5
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作者 LI Yonggang ZHOU Xiaobing ZHANG Yuanming 《Journal of Arid Land》 SCIE CSCD 2019年第4期579-594,共16页
Desert mosses, which are important stabilizers in desert ecosystems, are distributed patchily under and between shrubs. Mosses differ from vascular plants in the ways they take up nutrients. Clarifying their distribut... Desert mosses, which are important stabilizers in desert ecosystems, are distributed patchily under and between shrubs. Mosses differ from vascular plants in the ways they take up nutrients. Clarifying their distribution with ecological stoichiometry may be useful in explaining their mechanisms of living in different microhabitats. In this study, Syntrichia caninervis, the dominant moss species of moss crusts in the Gurbantunggut Desert, China, was selected to examine the study of stoichiometric characteristics in three microhabitats(under living shrubs, under dead shrubs and in exposed ground). The stoichiometry and enzyme activity of rhizosphere soil were analyzed. The plant function in the above-ground and below-ground parts of S. caninervis is significantly different, so the stoichiometry of the above-ground and below-ground parts might also be different. Results showed that carbon(C), nitrogen(N) and phosphorus(P) contents in the below-ground parts of S. caninervis were significantly lower than those in the above-ground parts. The highest N and P contents of the two parts were found under living shrubs and the lowest under dead shrubs. The C contents of the two parts did not differ significantly among the three microhabitats. In contrast, the ratios of C:N and C:P in the below-ground parts were higher than those in the above-ground parts in all microhabitats, with significant differences in the microhabitats of exposed ground and under living shrubs. There was an increasing trend in soil organic carbon(SOC), soil total nitrogen(STN), soil available phosphorous(SAP), and C:P and N:P ratios from exposed ground to under living shrubs and to under dead shrubs. No significant differences were found in soil total phosphorous(STP) and soil available nitrogen(SAN), or in ratios of C:N and SAN:SAP. Higher soil urease(SUE) and soil nitrate reductase(SNR) activities were found in soil under dead shrubs, while higher soil sucrase(STC) and soil β-glucosidase(SBG) activities were respectively found in exposed ground and under living shrubs. Soil alkaline phosphatase(AKP) activity reached its lowest value under dead shrubs, and there was no significant difference between the microhabitats of exposed ground and under living shrubs. Results indicated that the photosynthesis-related C of S. caninervis remained stable under the three microhabitats while N and P were mediated by the microhabitats. The growth strategy of S. caninervis varied in different microhabitats because of the different energy cycles and nutrient balances. The changes of stoichiometry in soil were not mirrored in the moss. We conclude that microhabitat could change the growth strategy of moss and nutrients cycling of moss patches. 展开更多
关键词 MOSS stoichiometry Syntrichia caninervis MICROHABITATS SOIL stoichiometry SOIL enzyme Gurbantunggut DESERT
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Carbon,nitrogen and phosphorus stoichiometry in Pinus tabulaeformis forest ecosystems in warm temperate Shanxi Province,north China 被引量:7
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作者 Ning Wang Fengzhen Fu +1 位作者 Baitian Wang Ruijun Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第6期1665-1673,共9页
Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the recipr... Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the reciprocal effects of C:N:P stoichiometry in plant–litter–soil systems. The present study analyzed C:N:P ratios in four age groups of Chinese pine, Pinus tabulaeformis Carr., forests in Shanxi Province, China: plantation young forests(AY,<20 year-old); plantation middle-aged forests(AM, 21–30 year-old); natural young forests(NY,<30 year-old); and natural middle-aged forests(NM,31–50 year-old). The average C:N:P ratios calculated for tree, shrub, and herbaceous leaves, litter, and soil(0–100 cm) were generally higher in NY followed by NM,AM, and AY. C:N and C:P ratios were higher in litter than in leaves and soils, and reached higher values in the litter and leaves of young forests than in middle-aged forests;however, C:N and C:P ratios were higher in soils of middle-aged forests than in young forests. N:P ratios were higher in leaves than in litter and soils regardless of stand age; the consistent N:P<14 values found in all forests indicated N limitations. With plant leaves, C:P ratios were highest in trees, followed by herbs and shrubs, indicating a higher efficiency in tree leaf formation. C:N ratios decreased with increasing soil depth, whereas there was no trend for C:P and N:P ratios. C:N:P stoichiometry of forest foliage did not exhibit a consistent variation according to stand age. Research on the relationships between N:P, and P, N nutrient limits and the characteristics of vegetation nutrient adaptation need to be continued. 展开更多
关键词 Pinus tabulaeformis Carr. Forest ecosystem Content of carbon Nitrogen and phosphorus ecological stoichiometry Warm temperate zone China
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Ecological stoichiometry of nitrogen, phosphorous, and sulfur in China's forests 被引量:3
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作者 Yuntao Wu Hongyan Liu +4 位作者 Zhaoliang Song Xiaomin Yang Zichuan Li Qian Hao Linan Liu 《Acta Geochimica》 EI CAS CSCD 2017年第3期525-530,共6页
Much attention has been paid to the stoichiometry of carbon(C), nitrogen(N), and phosphorus(P) because of their significance for plant growth and climate change. However, other nutrients, such as sulfur(S), are often ... Much attention has been paid to the stoichiometry of carbon(C), nitrogen(N), and phosphorus(P) because of their significance for plant growth and climate change. However, other nutrients, such as sulfur(S), are often ignored. In this study, we analyzed the stoichiometry of N, P, and S in leaves of 348 plant species in China's forests. The results show higher N content and higher molar ratios of N/P and P/S in Angiospermae than in Gymnospermae. At the family level, Ulmaceae absorbed more N and P from soils than other families, and Cupressaceae absorbed more S than other families. In addition,except for bamboo and other tropical forests, leaf N and P content of China's forests generally increased from low to middle latitudes and then slightly decreased or plateaued at high latitudes. Plant ecotypes, taxonomic groups, environmental conditions, atmospheric S precipitation, and soil-available N and P significantly affected the distribution and stoichiometry of leaf N, P, and S in China's forests.Our study indicates that China's forests are likely limited by P and S deficiencies which may increase in the future. 展开更多
关键词 FOREST stoichiometry Nitrogen Phosphorous SULFUR China
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Ecological stoichiometry and biomass response of Agropyron michnoi Roshev.under simulated N deposition in a sandy grassland,China 被引量:3
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作者 JIN Xiaoming YANG Xiaogang +4 位作者 ZHOU Zhen ZHANG Yingqi YU Liangbin ZHANG Jinghua LIANG Runfang 《Journal of Arid Land》 SCIE CSCD 2020年第5期741-751,共11页
Sandy grassland in northern China is a fragile ecosystem with poor soil fertility.Exploring how plant species regulate growth and nutrient absorption under the background of nitrogen(N)deposition is crucial for the ma... Sandy grassland in northern China is a fragile ecosystem with poor soil fertility.Exploring how plant species regulate growth and nutrient absorption under the background of nitrogen(N)deposition is crucial for the management of the sandy grassland ecosystem.We carried out a field experiment with six N levels in the Hulunbuir Sandy Land of China from 2014 to 2016 and explored the Agropyron michnoi Roshev.responses of both aboveground and belowground biomasses and carbon(C),N and phosphorus(P)concentrations in the plant tissues and soil.With increasing N addition,both aboveground and belowground biomasses and C,N and P concentrations in the plant tissues increased and exhibited a single-peak curve.C:N and C:P ratios of the plant tissues first decreased but then increased,while the trend for N:P ratio was opposite.The peak values of aboveground biomass,belowground biomass and C concentration in the plant tissues occurred at the level of 20 g N/(m2•a),while those of N and P concentrations in the plant tissues occurred at the level of 15 g N/(m2•a).The maximum growth percentages of aboveground and belowground biomasses were 324.2%and 75.9%,respectively,and the root to shoot ratio(RSR)decreased with the addition of N.N and P concentrations in the plant tissues were ranked in the order of leaves>roots>stems,while C concentration was ranked as roots>leaves>stems.The increase in N concentration in the plant tissues was the largest(from 34%to 162%),followed by the increase in P(from 10%to 33%)and C(from 8%to 24%)concentrations.The aboveground biomass was positively and linearly correlated with leaf C,N and P,and soil C and N concentrations,while the belowground biomass was positively and linearly correlated with leaf N and soil C concentrations.These results showed that the accumulation of N and P in the leaves caused the increase in the aboveground biomass,while the accumulation of leaf N resulted in the increase in the belowground biomass.N deposition can alter the allocation of C,N and P stoichiometry in the plant tissues and has a high potential for increasing plant biomass,which is conducive to the restoration of sandy grassland. 展开更多
关键词 BIOMASS nitrogen deposition plant tissue C N and P stoichiometry sandy grassland
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Inter-and intra-specific phenotypic variation of ecological stoichiometric traits in a mixed-oak secondary forest in China 被引量:2
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作者 Yueyao Feng Xuan Li +4 位作者 Biyao Zhou Rong Hu Huanchao Zhang Jiading Yang Yanming Fang 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2333-2347,共15页
Ecological stoichiometry provides a framework for the balance and flow of elements between organisms and ecosystems.Elemental phenotypes have an important influence on the environmental adaptation and ecological evolu... Ecological stoichiometry provides a framework for the balance and flow of elements between organisms and ecosystems.Elemental phenotypes have an important influence on the environmental adaptation and ecological evolution of plants.There have been few reports on inter-and intra-specific phenotypic variations of ecological stoichiometric traits for congeneric species in a mixed forest although such variations are well-documented at the species level at global,regional and local scales.In this study,total carbon(TC),nitrogen(TN),phosphorus(TP)and potassium(TK)were measured in leaves and the elemental phenotypes were statistically analyzed in four species of oaks—Quercus fabri,Q.serrata var.glandulifera,Q.acutissima and Q.variabilis—in a mixed-oak secondary forest in Yushan,Jiangsu,China.The average element concentrations in the four oak species were not relatively higher than previously reported for oaks from world and Chinese flora.Ecological stoichiometry traits were correlated with tree height and diameter at breast height,indicating that phosphorous and potassium were positively correlated with tree size,while carbon was negatively correlated,especially the relationship between oak growth and total carbon or total phosphorus was obvious,and the study concluded that this was because plant growth depended on phosphorus storage and had opposite effects on leaf carbon accumulation.Based on tree plasticity index and the coefficient of variation,there was medium variation in element concentrations.The plasticity index of total carbon levels was the lowest,and that of potassium the highest.Principal component analysis and cluster analysis showed that the intra-specific variation among the four oak species was higher than inter-specific variation.From the perspective of nutrient supply and ecological adaptation,this study creates a foundation for the management of secondary oak forest stands. 展开更多
关键词 ecological stoichiometry QUERCUS Elemental phenotype Intra-specific variation Inter-specific variation ecological evolution Nutrient supply
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Changes in ecological stoichiometry and nutrient resorption in Castanopsis hystrix plantations along an urbanization gradient in the lower subtropics 被引量:2
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作者 Feifan Li Bing Sun +1 位作者 Zhaowan Shi Nancai Pei 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2323-2331,共9页
The stoichiometry of carbon,nitrogen and phosphorous in plants can reflect the interactions between plants and their environment.The interplay between plant nutrients,climatic factors,and soil properties and the under... The stoichiometry of carbon,nitrogen and phosphorous in plants can reflect the interactions between plants and their environment.The interplay between plant nutrients,climatic factors,and soil properties and the underlying regulatory mechanisms are pillars of ecology but remain underexplored.In this study of plant C-N-P stoichiometry and nutrient resorption in Castanopsis hystrix groves in three cities(Guangzhou,Zhongshan,and Lechang)that represent an urban-rural gradient in Guangdong Province,South China,we explored potential relationships among NO_(2) concentrations,diameter at breast height(DBH),and resident human population.Mean annual temperature,mean annual precipitation,insolation duration per year,and the human resident population differed significantly among the three cities.Soil C-N-P was always highest in suburban Lechang,and the concentration of NO_(2) was highest in urban Guanghzou(55.33±0.67μg m^(-3))and positively correlated with the resident population and leaf N:P.Our findings suggest that C-N-P stoichiometry of C.hystrix was better explained by NO_(2)than by soil C-N-P stoichiometry and that nutrient resorption was better explained by leaf nutrients and DBH than by NO_(2) and soil stoichiometry.Our study supports the hypothesis that rapid urbanization influences NO_(2) concentrations and microclimate,which may jointly change the stoichiometry of plant nutrients in the forest ecosystems. 展开更多
关键词 ecological stoichiometry Nutrient cycling Plant-environment interaction Subtropical forest Urban–rural gradient
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Ecological stoichiometric comparison of plant-litter-soil system in mixed-species and monoculture plantations of Robinia pseudoacacia,Amygdalus davidiana,and Armeniaca sibirica in the Loess Hilly Region of China 被引量:1
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作者 Senbao Lu Yunming Chen +1 位作者 Jordi Sardans Josep Penuelas 《Forest Ecosystems》 SCIE CSCD 2023年第3期411-424,共14页
We examined how afforestation patterns impact carbon(C),nitrogen(N),and phosphorus(P)stoichiometry in the plant-litter-soil system.Plant leaf,branch,stem,and root,litter,and soil samples were collected from mixedspeci... We examined how afforestation patterns impact carbon(C),nitrogen(N),and phosphorus(P)stoichiometry in the plant-litter-soil system.Plant leaf,branch,stem,and root,litter,and soil samples were collected from mixedspecies plantations of Robinia pseudoacacia with Amygdalus davidiana(RPAD),R.pseudoacacia with Armeniaca sibirica(RPAS),and monocultures of R.pseudoacacia(RP),A.davidiana(AD),and A.sibirica(AS)in the Loess Hilly Region.The results showed that in mixed-species plantations,R.pseudoacacia had lower leaf N and P concentrations than in monocultures,while both A.davidiana and A.sibirica had higher leaf N and P concentrations.Soil P limited tree growth in both afforestation models.Mixing R.pseudoacacia with A.davidiana or A.sibirica reduced N-limitation during litter decomposition.Average soil total N and P concentrations were higher in RPAS than in RPAD,and both were higher than the corresponding monocultures.The average soil C:N ratio was the smallest in RPAS,while the average soil C:P ratio was larger in RPAS than in RP.A positive correlation between N and P concentrations,and between C:N and C:P ratios,was found in litter and all plant organs of mono-and mixedstands.Alternatively,for N concentration and C:N ratio,the correlations between plant(i.e.,leaf,branch,root)and litter and between plant and soil were inverse between plantation types.RPAD has an increased litter decomposition rate to release N and P,while RPAS has a faster rate of soil N mineralization.RPAD was the best plantation(mixed)to improve biogeochemical cycling,as soil nutrient restrictions,particularly for P-limitation,on trees growth were alleviated.This study thus provides insights into suitable tree selection and management by revealing C:N:P stoichiometry in the plant-litter-soil system under different afforestation patterns. 展开更多
关键词 stoichiometry PLANT LITTER Soil Tree mixture Loess Plateau
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Response of plant,litter,and soil C:N:P stoichiometry to growth stages in Quercus secondary forests on the Loess Plateau,China 被引量:1
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作者 Juanjuan Zhang Xinyang Li +4 位作者 Meng Chen Linjia Huang Ming Li Xu Zhang Yang Cao 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期595-607,共13页
Ecological stoichiometry is an important indicator of biogeochemical cycles and nutrient limitations in terrestrial ecosystems.However,little is known about the response of ecological stoichiometry to plant growth.In ... Ecological stoichiometry is an important indicator of biogeochemical cycles and nutrient limitations in terrestrial ecosystems.However,little is known about the response of ecological stoichiometry to plant growth.In this study,carbon(C),nitrogen(N),and phosphorus(P)concentrations were evaluated in plant tissues(trees,shrubs,and herbs),litter,and soil of young(≤40-year-old),middle-aged(41–60-year-old),near-mature(61–80-year-old),and mature(81–120-year-old)Quercus secondary forests on the Loess Plateau,China.Vegetation composition,plant biomass,and C stock were determined to illustrate their interaction with stoichiometry.Only tree biomass C signifi cantly increased with stand development.Leaf N and trunk P concentrationsgenerally increased,but branch P decreased with growth stage.Fine roots had the highest C and P concentrations at the middle-aged stage.In contrast,shrubs,herbs,litter,and soil C:N:P stoichiometry did not change signifi cantly during stand development.Leaf N and P were positively correlated with soil C,N,P,and their ratios.However,there was no signifi cant correlation between litter and leaves in terms of C:N:P stoichiometry.A redundancy analysis showed that soil N best explained leaf N and P variance,and tree biomass and C stock were related to biotic factors such as tree age and shrub biomass.Hierarchical partitioning analysis indicated that,compared with soil or litter variables,stand age only accounted for a relatively small proportion of leaf C,N,and P variation.Thus,secondary Quercus ecosystems might have inherent ability to maintain sensitive responses of metabolically active organs to environmental factors during stand aging.The results of this work help to elucidate the biogeochemical cycling of secondary forest ecosystems in tree development,provide novel insights into the adaptation strategies of plants in diff erent organs and growth stages,and could be used to guide fertilization programs and optimize forest structure. 展开更多
关键词 ecological stoichiometry Tree biomass C stock Understory plant Age Stand development
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Response of C:N:P in the plant-soil system and stoichiometric homeostasis of Nitraria tangutorum leaves in the oasis-desert ecotone,Northwest China 被引量:1
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作者 WEI Yajuan DANG Xiaohong +2 位作者 WANG Ji GAO Junliang GAO Yan 《Journal of Arid Land》 SCIE CSCD 2021年第9期934-946,共13页
Nitraria tangutorum nebkhas are widely distributed in the arid and semi-arid desert areas of China.The formation and development of N.tangutorum nebkhas are the result of the interaction between vegetation and the sur... Nitraria tangutorum nebkhas are widely distributed in the arid and semi-arid desert areas of China.The formation and development of N.tangutorum nebkhas are the result of the interaction between vegetation and the surrounding environment in the process of community succession.Different successional stages of N.tangutorum nebkhas result in differences in the community structure and composition,thereby strongly affecting the distribution of soil nutrients and ecosystem stability.However,the ecological stoichiometry of N.tangutorum nebkhas in different successional stages remains poorly understood.Understanding the stoichiometric homeostasis of N.tangutorum could provide insights into its adaptability to the arid and semi-arid desert environments.Therefore,we analyzed the stoichiometric characteristics of N.tangutorum in four successional stages,i.e.,rudimental,developing,stabilizing,and degrading stages using a homeostasis model in an oasis-desert ecotone of Northwest China.The results showed that soil organic carbon(SOC),total nitrogen(TN),and total phosphorus(TP)contents and their ratios in the 0-100 cm soil depth were significantly lower than the averages at regional and global scales and were weakly influenced by successional stages in the oasis-desert ecotone.TN and TP contents and C:N:P in the soil showed similar trends.Total carbon(TC)and TN contents in leaves were 450.69-481.07 and 19.72-29.35 g/kg,respectively,indicating that leaves of N.tangutorum shrubs had a high storage capacity for C and N.Leaf TC and TN contents and N:P ratio increased from the rudimental stage to the stabilizing stage and then decreased in the degrading stage,while the reverse trend was found for leaf C:N.Leaf TP content decreased from the rudimental stage to the degrading stage and changed significantly in late successional stages.N:P ratio was above the theoretical limit of 14,indicating that the growth of N.tangutorum shrubs was limited by P during successional stages.Leaf N,P,and N:P homeostasis in four successional stages was identified as''strictly homeostasis''.Redundancy analysis(RDA)revealed that soil acidity(pH)and the maximum water holding capacity were the main factors affecting C:N:P stoichiometric characteristics in N.tangutorum leaves.Our study demonstrated that N.tangutorum with a high degree of stoichiometric homeostasis could better cope with the arid desert environment. 展开更多
关键词 NEBKHAS ecological stoichiometry ecological adaptability successional stages arid area
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Decomposition dynamics and ecological stoichiometry of Quercus acutissima and Pinus densiflora litter in the Grain to Green Program Area of northern China
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作者 Jianni Sun Peng Gao +2 位作者 Haidong Xu Cheng Li Xiang Niu 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1613-1623,共11页
Litter decomposition and ecological stoichiometry of nutrient release is an important part of material cycling and energy flow in forest ecosystems.In a study of the ecological stoichiometry and nutrient release durin... Litter decomposition and ecological stoichiometry of nutrient release is an important part of material cycling and energy flow in forest ecosystems.In a study of the ecological stoichiometry and nutrient release during litter decomposition in a pine–oak forest ecosystem of the Grain to Green Program(GTGP)area of northern China,a typical pine and oak species(PDS:Pinus densiflora Sieb.,QAC:Quercus acutissima Carr.)were selected in the Taiyi Mountain study area.The ecological stoichiometry characteristics of carbon(C),nitrogen(N)and phosphorus(P)and litter decomposition dynamics were studied by field sampling and quantitative analyses.The results showed the following.(1)The decomposition dynamics of both litters was slow-fast-slow.The most important climatic factor affecting the litter decomposition rate from May to October was precipitation and temperature from November to April of the following year.(2)Throughout the 300-day study,in both litters,C of the two litters was released,N first accumulated and was then released,and P exhibited a release-accumulate-release pattern.(3)C:P was significantly higher than C:N and N:P(p<0.05);the C:N of PSD litter was higher than that of QAC(p<0.05),but the N:P of QAC litter was higher than that of PSD litter(p<0.05).The C:N of both litters was very high in the study area,indicating that the nutrient release ability during litter decomposition in the two typical pine–oak forest ecosystems was relatively weak;therefore,more attention should be paid to nitrogen-fixing species and mixed forests in the GTGP area of northern China. 展开更多
关键词 Decomposition dynamics ecological stoichiometry LITTER Pinus densiflora Quercus acutissima Grain to Green Program(GTGP)
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条形码识别SoC芯片实现自动化ECO
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作者 曾云泽 林思杰 +1 位作者 卢朝辉 王仁平 《电子制作》 2024年第18期25-28,共4页
工程变更指令(Engineering Change Order,ECO)在芯片设计当中是一种非常有效地解决芯片功能或时序问题的方法。本文以自研的条形码识别芯片为例,提出一种结合逻辑验证的从寄存器传输级(Register Transfer Level,RTL)电路到GDSII版图的... 工程变更指令(Engineering Change Order,ECO)在芯片设计当中是一种非常有效地解决芯片功能或时序问题的方法。本文以自研的条形码识别芯片为例,提出一种结合逻辑验证的从寄存器传输级(Register Transfer Level,RTL)电路到GDSII版图的自动化ECO流程。介绍了基于综合工具、逻辑验证工具,布局布线工具的自动化ECO流程应用。同时围绕Conformal工具进行逻辑等效验证及ECO补丁生成,能够更直观地了解设计的变更点。且所有操作均可由自动化脚本完成,相较于传统的ECO流程,自动化程度更高,通过调用的综合工具使电路能更好地满足时序约束,大大降低了时间和人力成本,加快了芯片生产周期。 展开更多
关键词 芯片设计 工程变更 eco 逻辑验证
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Conformal ECO寄存器新增的扫描链自动化接入方案
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作者 曾子豪 《电子技术应用》 2024年第8期17-20,共4页
随着芯片规模的增加,ECO的需求和大小也随之增加,其中当新增寄存器数量达到百位量级时,人工接入扫描链难度也将急剧上升。基于Cadence的Conformal和Innovus等工具,在综合考量逻辑正确性和中后端物理实现可行性的基础上,采用归一思路下的... 随着芯片规模的增加,ECO的需求和大小也随之增加,其中当新增寄存器数量达到百位量级时,人工接入扫描链难度也将急剧上升。基于Cadence的Conformal和Innovus等工具,在综合考量逻辑正确性和中后端物理实现可行性的基础上,采用归一思路下的“S”型连线和room值下的再分组等方法,实现了上述问题的自动化和高效化解决,在逻辑上确保了时钟域一致性等问题,物理上同时兼顾了布局布线优化和最大扫描链长度。并且其自动化的高效性,在项目实践中能够快速完成上百数量寄存器的扫描链接入。 展开更多
关键词 Conformal eco 扫描链 新增寄存器 自动化
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Responses of soil stoichiometry and soil enzyme activities in the different distance around opencast coal mine of the Hulun Buir Grassland of China
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作者 Yinli Bi Nan Guo +2 位作者 Yanxu Zhang Xianglei Li Ziheng Song 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期221-231,共11页
The objectives of this study were to explore the changes in soil stoichiometry and enzyme activities at different distances from an opencast coal mine in the Hulun Buir Grassland of China. Four transects were establis... The objectives of this study were to explore the changes in soil stoichiometry and enzyme activities at different distances from an opencast coal mine in the Hulun Buir Grassland of China. Four transects were established on north and east sides of the opencast coal mining area, and samples were collected at 50 m, 550 m, and 1550 m from the pit on each transect. Control samples were collected from a grassland station 8 km from the opencast coal mining area that was not disturbed by mining. Four replicate soil samples were collected at each point on the four transects. Soil physicochemical properties and enzyme activities were determined, and correlations between soil properties and stoichiometric ratios and enzyme activities were explored using redundancy analysis. The increase in distance from mining did not significantly affect soil properties, although soil urease activity was significantly lower than that of the control area. Soil properties 1550 m from the mine pit were similar to those at the grassland control. In addition, soil total nitrogen had the greatest effect on soil stoichiometry, and soil total potassium had the greatest effect on soil enzyme activities. Coal dust from opencast mining might be the main factor affecting soil stoichiometry and enzyme activities. The results of this study provide direction for the next step in studying the influence of mining areas on soil properties and processes. 展开更多
关键词 Opencast coal mine Soil stoichiometry Soil enzyme activities DISTANCE GRASSLAND
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Atmospheric nitrogen deposition affects forest plant and soil system carbon:nitrogen:phosphorus stoichiometric flexibility:A meta-analysis
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作者 Xiyan Jiang Xiaojing Wang +7 位作者 Yaqi Qiao Yi Cao Yan Jiao An Yang Mengzhou Liu Lei Ma Mengya Song Shenglei Fu 《Forest Ecosystems》 SCIE CSCD 2024年第3期307-317,共11页
Background:Nitrogen(N)deposition affects forest stoichiometric flexibility through changing soil nutrient availability to influence plant uptake.However,the effect of N deposition on the flexibility of carbon(C),N,and... Background:Nitrogen(N)deposition affects forest stoichiometric flexibility through changing soil nutrient availability to influence plant uptake.However,the effect of N deposition on the flexibility of carbon(C),N,and phosphorus(P)in forest plant-soil-microbe systems remains unclear.Methods:We conducted a meta-analysis based on 751 pairs of observations to evaluate the responses of plant,soil and microbial biomass C,N and P nutrients and stoichiometry to N addition in different N intensity(050,50–100,>100 kg·ha^(-1)·year^(-1)of N),duration(0–5,>5 year),method(understory,canopy),and matter(ammonium N,nitrate N,organic N,mixed N).Results:N addition significantly increased plant N:P(leaf:14.98%,root:13.29%),plant C:P(leaf:6.8%,root:25.44%),soil N:P(13.94%),soil C:P(10.86%),microbial biomass N:P(23.58%),microbial biomass C:P(12.62%),but reduced plant C:N(leaf:6.49%,root:9.02%).Furthermore,plant C:N:P stoichiometry changed significantly under short-term N inputs,while soil and microorganisms changed drastically under high N addition.Canopy N addition primarily affected plant C:N:P stoichiometry through altering plant N content,while understory N inputs altered more by influencing soil C and P content.Organic N significantly influenced plant and soil C:N and C:P,while ammonia N changed plant N:P.Plant C:P and soil C:N were strongly correlated with mean annual precipitation(MAT),and the C:N:P stoichiometric flexibility in soil and plant under N addition connected with soil depth.Besides,N addition decoupled the correlations between soil microorganisms and the plant.Conclusions:N addition significantly increased the C:P and N:P in soil,plant,and microbial biomass,reducing plant C:N,and aggravated forest P limitations.Significantly,these impacts were contingent on climate types,soil layers,and N input forms.The findings enhance our comprehension of the plant-soil system nutrient cycling mechanisms in forest ecosystems and plant strategy responses to N deposition. 展开更多
关键词 C:N:P stoichiometry META-ANALYSIS Forest ecosystem Nitrogen addition form Nutrient cycles
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Social and Economic Considerations for Creating Sustainable Climate Change Haven Communities
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作者 Elizabeth C. Hirschman William Bourgin +6 位作者 Angel Castilla Caitlin Glover Caitlyn Justice Manuel Munoz Braydon Thompson Justin Snider Olivia Toomer 《Journal of Environmental Protection》 2024年第1期76-93,共18页
As Climate Change Haven Communities are constructed across the Northern Hemisphere, it will be necessary to attract two types of migrants to populate them. The first group consists of professionals and companies in ec... As Climate Change Haven Communities are constructed across the Northern Hemisphere, it will be necessary to attract two types of migrants to populate them. The first group consists of professionals and companies in eco-sustainable businesses, such as law firms, insurance companies, investment firms, banking, technological innovation, mass media, medical research and pharmaceutical research. The second group will consist of persons engaged in organic/eco-sustainable agriculture whose crops and animal husbandry practices can be transferred successfully to Climate Change Haven regions. The present research focuses on the social and economic variables that must be taken into account to insure that each new Climate Change Haven Community becomes successfully integrated with the local population and forms a cohesive, harmonious social structure. Examples are given from the United States, France, Spain, Portugal and Italy. 展开更多
关键词 Climate Change Haven Community Sustainability Organic/eco Farming Internal Migration Social Integration
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Effects of Vegetation Restoration Age on Soil C:N:P Stoichiometry in Yellow River Delta Coastal Wetland of China
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作者 CAO Qixue WANG Xiajie +7 位作者 CHU Xiaojing ZHAO Mingliang WANG Lianjing SONG Weimin LI Peiguang ZHANG Xiaoshuai XU Shendong HAN Guangxuan 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1045-1059,共15页
Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this s... Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this study,we examined the re-sponses of soil C,N,and P contents and their stoichiometric ratios to vegetation restoration age,focusing on below-ground processes and their relationships to aboveground vegetation community characteristics.We conducted an analysis of temporal gradients based on the'space for time'method to synthesize the effects of restoration age on soil C:N:P stoichiometry in the Yellow River Delta wetland of China.The findings suggest that the combined effects of restoration age and soil depth create complex patterns of shifting soil C:N:P stoichiometry.Specifically,restoration age significantly increased all topsoil C:N:P stoichiometries,except for soil total phosphorus(TP)and the C:N ratio,and slightly affected subsoil C:N:P stoichiometry.The effects of restoration age on the soil C:N ratio was well constrained owing to the coupled relationship between soil organic carbon(SOC)and total nitrogen(TN)contents,while soil TP con-tent was closely related to changes in plant species diversity.Importantly,we found that the topsoil C:N:P stoichiometry was signific-antly affected by plant species diversity,whereas the subsoil C:N:P stoichiometry was more easily regulated by pH and electric con-ductivity(EC).Overall,this study shows that vegetation restoration age elevated SOC and N contents and alleviated N limitation,which is useful for further assessing soil C:N:P stoichiometry in coastal restoration wetlands. 展开更多
关键词 coastal wetland restoration age soil C:N:P stoichiometry soil properties plant species diversity Yellow River Delta of China
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中鼎股份荣获EcoVadis可持续发展银牌评级
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《液压气动与密封》 2024年第1期87-87,共1页
2023年11月,中鼎股份在2023年度Eco Vadis可持续发展认证评级中取得60/100分,并荣获企业社会责任银牌勋章。中鼎股份已连续两年参加Eco Vadis可持续发展评级,本次评级范围覆盖中鼎股份所有分公司。
关键词 企业社会责任 中鼎股份 可持续发展 评级 eco
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骏马两公司分获EcoVadis CSR银牌/铜牌评级
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《特种橡胶制品》 CAS 2024年第1期20-20,共1页
据行业媒体消息,EcoVadis是全球公认的企业社会责任权威评价机构,为全球供应商提供环境、劳工和人权、商业道德和可持续采购等的认证审核,涵盖近200个行业、160多个国家和地区。在本次EcoVadis评选活动中,骏马化纤股份有限公司和张家港... 据行业媒体消息,EcoVadis是全球公认的企业社会责任权威评价机构,为全球供应商提供环境、劳工和人权、商业道德和可持续采购等的认证审核,涵盖近200个行业、160多个国家和地区。在本次EcoVadis评选活动中,骏马化纤股份有限公司和张家港市骏马钢丝帘线有限公司均表现突出。其中,骏马化纤股份公司获得了65分(高分),获得EcoVadis CSR银牌评级;骏马钢丝帘线公司获得55分,获得了EcoVadis CSR铜牌评级。 展开更多
关键词 企业社会责任 认证审核 商业道德 钢丝帘线 CSR 评级 权威评价 eco
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RE而意用ECO-WORKING“环乐同创”
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作者 灰原 《中国自行车》 2024年第4期90-93,共4页
2024年5月1日至6月2日,RE而意与小布(BROMPTON)、FREITAG、抱朴再生BOTTLOOP合作,在上海张园呈现了一场精彩纷呈的展览。本次展览的主题为“ECO-WORKING!环乐同创”。展览以“倡导时尚、环保、可持续的生活方式”为主导,展现一系列具有... 2024年5月1日至6月2日,RE而意与小布(BROMPTON)、FREITAG、抱朴再生BOTTLOOP合作,在上海张园呈现了一场精彩纷呈的展览。本次展览的主题为“ECO-WORKING!环乐同创”。展览以“倡导时尚、环保、可持续的生活方式”为主导,展现一系列具有长效设计、实用、可循环利用且令人愉悦的时尚单品。 展开更多
关键词 可循环利用 ING eco 可持续的
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ECO离子色谱测定水中碘化物
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作者 钱凡 袁少伟 +1 位作者 焦慧 欣阳 《中国食品工业》 2024年第13期115-118,共4页
目的:建立测定饮用水中碘化物的离子色谱法。方法:采用碳酸根体系离子色谱法,选用瑞士万通ECO型离子色谱仪,MetrosepASupp5-150/4.0分离色谱柱,碳酸钠-重碳酸钠浓度为3.2 mmol/L-1.0 mmol/L+10 mL丙酮淋洗液,浓度为0.1 mol/L硫酸再生液... 目的:建立测定饮用水中碘化物的离子色谱法。方法:采用碳酸根体系离子色谱法,选用瑞士万通ECO型离子色谱仪,MetrosepASupp5-150/4.0分离色谱柱,碳酸钠-重碳酸钠浓度为3.2 mmol/L-1.0 mmol/L+10 mL丙酮淋洗液,浓度为0.1 mol/L硫酸再生液,水样经过英蓝在线超滤系统过滤进行分析。结果:检测方法的线性相关系数好(r>0.999),线性范围广、检出限浓度较低(0.0004 mg/L,RSD<0.62%),样品加标回收率范围在87.5%~99.7%。结论:本方法灵敏度高、结果准确、操作简便,适用于水中碘化物的测定。 展开更多
关键词 eco离子色谱 阴离子 分析
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